Merge pull request 'Remove unimplemented CLI options' (#209 ) from feat/remove-unimplemented-cli-options into evaluation-of-codebase-by-human

Reviewed-on: #209
Satisfy cppcheck CLI and logger checks
2026-08-11 21:17:52 +02:00 · 2026-08-11 21:14:56 +02:00 · 2026-08-11 21:12:00 +02:00 · 2026-08-11 21:08:54 +02:00 · 2026-08-11 20:59:06 +02:00 · 2026-08-11 20:26:15 +02:00
27 changed files with 1168 additions and 708 deletions
@@ -206,7 +206,7 @@ tea pr close <number> --repo TapTap/FastSync
 ## Common pitfalls
- **`__thread` on shared SSL context**: io_ssl must NOT be thread-local — worker threads inherit the SSL context from the main thread. Use regular `static SSL* io_ssl`.
+- **Per-thread SSL context**: `io_ssl` is stored per-thread (`static __thread SSL* io_ssl`). Each thread that performs protocol I/O must call `io_set_ssl()` to install its own SSL object before using `send_*` / `receive_*` primitives. The main thread's SSL context is not automatically inherited by worker threads.
 - **SSL WANT_READ/WANT_WRITE retry**: Always retry on `SSL_ERROR_WANT_READ` and `SSL_ERROR_WANT_WRITE` in `send_n_data`/`receive_n_data`. Removing these breaks TLS multithreaded transfers.
 - **clang-format version**: The CI image uses clang-format 18. Always format inside the CI Docker container for exact match.
 - **Merge order matters**: Merge the most comprehensive branch first, then smaller ones, to minimize conflicts when creating a combined branch.
@@ -79,8 +79,9 @@ set(TEST_INCLUDES tests src/shared src/server src/client)
 # Monolithic test binary (backward compatible)
 file(GLOB TEST_SRCS "tests/test_*.c" "tests/runner.c")
-add_executable(tests ${TEST_SRCS} ${SHARED_SRCS} src/client/scanner.c)
+add_executable(tests ${TEST_SRCS} ${SHARED_SRCS} src/client/scanner.c src/client/client_cli.c)
 target_include_directories(tests PRIVATE ${TEST_INCLUDES})
 target_compile_definitions(tests PRIVATE FASTSYNC_TEST_BUILD)
 target_link_libraries(tests PRIVATE ${TEST_LIBS})
 add_test(NAME unit_all COMMAND tests)
@@ -40,12 +40,10 @@ A high-performance file synchronization system with SSH and TCP transport, TLS e
 - Optional progress display with throughput
 - Bandwidth limiting via token-bucket algorithm
 - Configurable I/O and connection timeouts (`--timeout`, `--contimeout`)
 - Quiet mode (`-q`/`--quiet`) suppresses all non-error output
 - Backup overwritten files (`--backup`) with optional directory (`--backup-dir`)
 - Transfer statistics summary (`--stats`)
 - Maximum directory depth control (`--max-depth`)
 - Log file output (`--log-file`)
 - Configurable multithreaded queue size (`--queue-size`)
 - Exclude patterns from file (`--exclude-from`)
 ### Server
@@ -114,8 +112,6 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 | `-n, --dry-run` | Scan and print what would be transferred |
 | `-p <port>` | SSH port (default: 22) |
 | `-v, --verbose` | Enable debug logging |
 | `-q, --quiet` | Suppress all non-error output |
 | `--silent` | Alias for `--quiet` |
 | `--progress` | Show real-time transfer speed |
 | `--delete` | Delete files on receiver not present in source |
 | `--exclude <pattern>` | Exclude files matching glob pattern (repeatable) |
@@ -133,7 +129,6 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 | `--stats` | Print transfer statistics at end (bytes, files, timing) |
 | `--max-depth <n>` | Maximum directory depth to recurse (0 = unlimited, default: 0) |
 | `--log-file <path>` | Write log messages to file instead of stderr |
 | `--queue-size <n>` | Queue capacity for multithreaded mode (default: 100) |
 | `--source-dir <path>` | Source directory (overrides `FASTSYNC_SOURCE_DIR`) |
 | `--dest-dir <path>` | Server destination directory (overrides `FASTSYNC_DEST_DIR`) |
 | `--save-to-disk` | Write received files to disk |
@@ -177,7 +172,7 @@ Abort (`STATUS_ABORT`) may be sent at any point. On receipt the server cleans up
 1. **Chunk** — collection of files (~10 MB total by default)
 2. **File** — path, content (`Data`), optional `FileMetadata` pointer
 3. **FileMetadata** — `mode`, `uid`, `gid`, `mtime_sec`, `mtime_nsec`
-4. **Config** — runtime parameters (transported over wire, TLS settings excluded). Includes `timeout`, `contimeout`, `quiet`, `backup`, `backup_dir`, `stats`, `max_depth`, `log_file`, `queue_size`.
+4. **Config** — runtime parameters (transported over wire, TLS settings excluded). Includes `timeout`, `contimeout`, `backup`, `backup_dir`, `stats`, and `max_depth`.
 5. **Queue** — thread-safe bounded queue with condition variables
 6. **DirectoryScanner** — recursive BFS traversal with exclude and include pattern support, max-depth enforcement
@@ -294,8 +289,8 @@ Place the `fastsync-server` binary in the remote `$PATH`. The client runs `ssh u
 # Bandwidth limit to 1 MB/s
 ./build/client --bwlimit 1024 /src user@host:/dst
-# With timeouts, quiet mode, and stats
+# With timeouts and stats
-./build/client --timeout 60 --contimeout 15 --quiet --stats /src user@host:/dst
+./build/client --timeout 60 --contimeout 15 --stats /src user@host:/dst
 # Backup overwritten files to a directory
 ./build/client --backup --backup-dir /backups /src user@host:/dst
@@ -303,9 +298,6 @@ Place the `fastsync-server` binary in the remote `$PATH`. The client runs `ssh u
 # Exclude patterns from file, limit depth
 ./build/client --exclude-from ignore.txt --max-depth 3 /src user@host:/dst
 # Custom queue size for multithreading
 ./build/client -m --queue-size 200 /src user@host:/dst
 # Log to file
 ./build/client --log-file /tmp/fastsync.log /src user@host:/dst
@@ -332,7 +324,7 @@ The benchmark prints throughput metrics, best configuration, and speedup vs rsyn
 1. Chunk size (~10 MB default) balances memory and transfer efficiency
 2. Compression level trades CPU for bandwidth
 3. `sendfile()` bypasses userspace — ~2× faster on localhost for large files
-4. Multithreading scales with core count; `--queue-size` controls pipeline buffering
+4. Multithreading scales with core count and uses memory-based pipeline sizing
 5. Metadata transfer adds negligible overhead (~24 bytes per file when enabled)
 6. SSH socketpair buffer set to 1 MB for improved pipe throughput
 7. SSH ControlMaster reuses connections across repeated invocations
@@ -0,0 +1,273 @@
 # Rsync Feature Compatibility
 This document maps rsync's full feature set to FastSync's current implementation status.
 ## Summary
 | Status | Count | Description |
 |--------|-------|-------------|
 | ✅ Implemented | 34 | Feature works end-to-end |
 | 🔀 Alt Arg | 3 | Functionality exists but under different flag/semantics |
 | ⚠️ Partial | 1 | Flag parsed/stored but behavior incomplete |
 | ❌ Not Implemented | 98 | Flag not recognized or no behavior |
 | **Total** | **136** | |
 ---
 ## 1. General Options
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-a`, `--archive` | Archive mode is -rlptgoD | 🔀 Alt Arg | Maps to -c -m -M (compression + multithread + metadata) |
 | `-v`, `--verbose` | Increase verbosity | ✅ Implemented | Sets `log_level=DEBUG` |
 | `-q`, `--quiet` | Suppress non-error messages | ❌ Not Implemented | Removed because it had no effect |
 | `--help` | Show help | ✅ Implemented | Prints usage and exits; `-h` is not accepted |
 | `-V`, `--version` | Print version | ✅ Implemented | |
 | `--info=FLAGS` | Fine-grained info verbosity | ❌ Not Implemented | Removed because it had no effect |
 | `--debug=FLAGS` | Fine-grained debug verbosity | ❌ Not Implemented | Removed because it had no effect |
 | `--stderr=MODE` | Change stderr output mode | ❌ Not Implemented | |
 | `--no-motd` | Suppress daemon MOTD | ❌ Not Implemented | |
 | `--exclude=PATTERN` | Exclude files matching pattern | ✅ Implemented | Glob matching in scanner |
 | `--include=PATTERN` | Include files matching pattern | ✅ Implemented | Glob matching in scanner |
 | `-C`, `--cvs-exclude` | Auto-ignore CVS files | ❌ Not Implemented | Removed because it had no effect |
 ## 2. Modifying Output
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--stats` | Give transfer stats | ✅ Implemented | Prints file/byte counts |
 | `-h`, `--human-readable` | Human-readable numbers | ❌ Not Implemented | Removed because it had no effect |
 | `-i`, `--itemize-changes` | Per-file change summary | ❌ Not Implemented | Removed because it had no effect |
 | `--progress` | Show progress | ✅ Implemented | Progress callback in sender |
 | `-P` | Same as --partial --progress | ❌ Not Implemented | |
 | `--out-format=FORMAT` | Custom output format | ❌ Not Implemented | Removed because it had no effect |
 | `--log-file=FILE` | Log to file | ✅ Implemented | `log_file` config field |
 | `--log-file-format=FMT` | Log format | ❌ Not Implemented | |
 | `--8-bit-output` | Leave high-bit chars unescaped | ❌ Not Implemented | |
 | `--list-only` | List files instead of copying | ❌ Not Implemented | Removed because it had no effect |
 ## 3. File Selection
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--exclude-from=FILE` | Read exclude patterns from file | ✅ Implemented | Reads patterns from file |
 | `--include-from=FILE` | Read include patterns from file | ✅ Implemented | Reads patterns from file |
 | `--filter=RULE` | Add file-filtering rule | ❌ Not Implemented | Removed because it had no effect |
 | `--files-from=FILE` | Read source file list from file | ❌ Not Implemented | Removed because it had no effect |
 | `-0`, `--from0` | Delimit *-from files with NULs | ❌ Not Implemented | |
 | `--max-size=SIZE` | Skip files larger than SIZE | ✅ Implemented | `max_size` in scanner |
 | `--min-size=SIZE` | Skip files smaller than SIZE | ✅ Implemented | `min_size` in scanner |
 | `-I`, `--ignore-times` | Don't skip files matching size+time | ❌ Not Implemented | |
 | `--size-only` | Skip based on size only | ❌ Not Implemented | |
 | `-@`, `--modify-window=NUM` | Mod-time comparison accuracy | ❌ Not Implemented | |
 | `--existing` | Skip creating new files on receiver | ❌ Not Implemented | |
 | `--ignore-existing` | Skip updating existing files | ❌ Not Implemented | |
 | `--remove-source-files` | Sender removes synced files | ❌ Not Implemented | |
 ## 4. Directory Options
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-r`, `--recursive` | Recurse into directories | ✅ Implemented | Default behavior |
 | `-R`, `--relative` | Use relative path names | ❌ Not Implemented | Removed because it had no effect |
 | `--no-implied-dirs` | Don't send implied dirs with -R | ❌ Not Implemented | |
 | `-d`, `--dirs` | Transfer dirs without recursing | ❌ Not Implemented | |
 | `--mkpath` | Create missing path components | ❌ Not Implemented | |
 ## 5. Transfer Modifications
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-u`, `--update` | Skip files newer on receiver | ❌ Not Implemented | Removed because it had no effect |
 | `--inplace` | Update files in-place | ✅ Implemented | Direct write mode |
 | `--append` | Append data to shorter files | ❌ Not Implemented | Removed because it had no effect |
 | `--append-verify` | Append with old-data checksum | ❌ Not Implemented | Removed because it had no effect |
 | `-W`, `--whole-file` | Copy whole file (no delta) | ❌ Not Implemented | |
 | `--block-size=SIZE` | Force checksum block-size | ⚠️ Partial | Parsed as `--delta-block`; controls delta transfer block size |
 ## 6. Destination Handling
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-n`, `--dry-run` | Trial run with no changes | ✅ Implemented | `dry_run` config field |
 | `-b`, `--backup` | Make backups of overwritten files | ✅ Implemented | Backup before overwrite |
 | `--backup-dir=DIR` | Backup directory hierarchy | ✅ Implemented | `backup_dir` config field |
 | `--suffix=SUFFIX` | Backup suffix (default ~) | ✅ Implemented | `suffix` config field |
 | `--delay-updates` | Put updated files in place at end | ❌ Not Implemented | |
 ## 7. Deletion
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--delete` | Delete extraneous files from dest | ✅ Implemented | `use_delete` config field |
 | `--delete-before` | Delete before transfer | ❌ Not Implemented | Removed because it had no effect |
 | `--delete-during` | Delete during transfer | ❌ Not Implemented | |
 | `--delete-delay` | Find deletions during, delete after | ❌ Not Implemented | |
 | `--delete-after` | Delete after transfer | ❌ Not Implemented | Removed because it had no effect |
 | `--delete-excluded` | Also delete excluded files | ❌ Not Implemented | Removed because it had no effect |
 | `--max-delete=NUM` | Max files to delete | ❌ Not Implemented | Removed because it had no effect |
 | `--ignore-errors` | Delete even with I/O errors | ❌ Not Implemented | |
 | `--force` | Force deletion of non-empty dirs | ❌ Not Implemented | |
 | `--prune-empty-dirs` | Prune empty dir chains | ❌ Not Implemented | Removed because it had no effect |
 ## 8. Metadata Preservation
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-M`, `--preserve` | Preserve file metadata | ✅ Implemented | Mode, uid, gid, mtime |
 | `-p`, `--perms` | Preserve permissions | 🔀 Alt Arg | `-p` means SSH port; permissions preserved via `-M`/`--preserve` |
 | `-o`, `--owner` | Preserve owner | ✅ Implemented | Part of -M |
 | `-g`, `--group` | Preserve group | ✅ Implemented | Part of -M |
 | `-t`, `--times` | Preserve modification times | ✅ Implemented | Part of -M |
 | `-E`, `--executability` | Preserve executability | ❌ Not Implemented | |
 | `--chmod=CHMOD` | Affect file permissions | ❌ Not Implemented | |
 | `-A`, `--acls` | Preserve ACLs | ❌ Not Implemented | Removed because it had no effect |
 | `-X`, `--xattrs` | Preserve extended attributes | ❌ Not Implemented | Removed because it had no effect |
 | `-H`, `--hard-links` | Preserve hard links | ❌ Not Implemented | Removed because it had no effect |
 | `-D` | Same as --devices --specials | ❌ Not Implemented | Removed because device-file handling is not implemented |
 | `--devices` | Preserve device files | ❌ Not Implemented | Removed because it had no effect |
 | `--specials` | Preserve special files | ❌ Not Implemented | |
 | `--copy-devices` | Copy device contents as file | ❌ Not Implemented | |
 | `--write-devices` | Write to devices as files | ❌ Not Implemented | |
 | `-U`, `--atimes` | Preserve access times | ❌ Not Implemented | |
 | `-N`, `--crtimes` | Preserve create times | ❌ Not Implemented | |
 | `-O`, `--omit-dir-times` | Omit dirs from --times | ❌ Not Implemented | |
 | `-J`, `--omit-link-times` | Omit symlinks from --times | ❌ Not Implemented | |
 | `--super` | Receiver attempts super-user activities | ❌ Not Implemented | |
 | `--fake-super` | Store/recover privileged attrs via xattrs | ❌ Not Implemented | |
 ## 9. Symlink Handling
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-l`, `--links` | Copy symlinks as symlinks | ⚠️ Partial | Scanner includes symlinks; target path not transmitted |
 | `-L`, `--copy-links` | Transform symlink to referent | ✅ Implemented | `copy_links` config field |
 | `--copy-unsafe-links` | Transform unsafe symlinks | ✅ Implemented | `copy_unsafe_links` config field |
 | `--safe-links` | Ignore symlinks outside tree | ✅ Implemented | `safe_links` config field |
 | `--munge-links` | Munge symlinks for safety | ❌ Not Implemented | |
 | `-k`, `--copy-dirlinks` | Transform symlink to dir | ❌ Not Implemented | |
 | `-K`, `--keep-dirlinks` | Treat symlinked dir as dir | ❌ Not Implemented | |
 ## 10. Sparse & Device
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-S`, `--sparse` | Sparse block handling | ✅ Implemented | `preserve_sparse` config field |
 | `--preallocate` | Allocate dest files before writing | ❌ Not Implemented | |
 ## 11. Checksum & Comparison
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--checksum` | Skip based on checksum | ❌ Not Implemented | Removed because it had no effect; `-c` means compression |
 | `--checksum-choice=STR` | Choose checksum algorithm | ❌ Not Implemented | xxHash used internally |
 | `--compare-dest=DIR` | Compare dest files relative to DIR | ❌ Not Implemented | Removed because it had no effect |
 | `--copy-dest=DIR` | Include copies of unchanged files | ❌ Not Implemented | Removed because it had no effect |
 | `--link-dest=DIR` | Hardlink to files when unchanged | ❌ Not Implemented | Removed because it had no effect |
 | `--fuzzy`, `--no-fuzzy` | Find similar file for basis | ❌ Not Implemented | |
 ## 12. Compression
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-z`, `--compress` | Compress file data | 🔀 Alt Arg | Always uses zstd (rsync supports multiple algorithms) |
 | `--compress-choice=STR` | Choose compression algorithm | ❌ Not Implemented | Removed because it had no effect; FastSync always uses zstd |
 | `--compress-level=NUM` | Set compression level | ✅ Implemented | 1-22, default 5 |
 | `--compress-threads=NUM` | Set compression threads | ❌ Not Implemented | |
 | `--skip-compress=LIST` | Skip compress for suffixes | ❌ Not Implemented | Internal skip for hardcoded types; not user-configurable |
 ## 13. Connectivity
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `-e`, `--rsh=COMMAND` | Remote shell to use | ❌ Not Implemented | Removed; SSH invokes `ssh` directly |
 | `--rsync-path=PROGRAM` | rsync binary on remote | ❌ Not Implemented | Removed; use `--fastsync-server-path` |
 | `--port=PORT` | Alternate daemon port | ✅ Implemented | `server_port` config field |
 | `--sockopts=OPTIONS` | Custom TCP options | ❌ Not Implemented | |
 | `--blocking-io` | Use blocking I/O for remote shell | ❌ Not Implemented | |
 | `--outbuf=N\|L\|B` | Set output buffering | ❌ Not Implemented | |
 | `--address=ADDRESS` | Bind address for outgoing socket | ❌ Not Implemented | Removed because it had no effect |
 | `-4`, `--ipv4` | Prefer IPv4 | ❌ Not Implemented | Removed because it had no effect |
 | `-6`, `--ipv6` | Prefer IPv6 | ❌ Not Implemented | Removed because it had no effect |
 ## 14. Daemon Mode
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--daemon` | Run as rsync daemon | ❌ Not Implemented | Removed because it had no effect |
 | `--config=FILE` | Alternate rsyncd.conf file | ❌ Not Implemented | Removed because it had no effect |
 | `--dparam=OVERRIDE` | Override global daemon config | ❌ Not Implemented | |
 | `--no-detach` | Don't detach from parent | ❌ Not Implemented | |
 | `--password-file=FILE` | Read daemon password from file | ❌ Not Implemented | |
 | `--early-input=FILE` | Use FILE for daemon early exec | ❌ Not Implemented | |
 ## 15. Safety & Security
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | Path escape detection | Ensure files stay within root | ✅ Implemented | `has_path_traversal()` + realpath |
 | Symlink-safe delete | Skip symlinks in delete walk | ✅ Implemented | `delete_extras_walk()` |
 | Protocol version check | Verify compatible versions | ✅ Implemented | `config_receive()` |
 | Max data/string/chunk sizes | Prevent OOM attacks | ✅ Implemented | Per-message limits |
 | Per-connection memory limit | 1GB per connection | ✅ Implemented | `MAX_CONNECTION_MEMORY` |
 | `--trust-sender` | Trust remote sender's file list | ❌ Not Implemented | |
 | `--old-args` | Disable modern arg protection | ❌ Not Implemented | |
 | `--ignore-missing-args` | Ignore missing source args | ❌ Not Implemented | |
 | `--delete-missing-args` | Delete missing source args | ❌ Not Implemented | |
 ## 16. Batch Operations
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--write-batch=FILE` | Write batched update to file | ❌ Not Implemented | |
 | `--only-write-batch=FILE` | Write batch without updating dest | ❌ Not Implemented | |
 | `--read-batch=FILE` | Read batched update from file | ❌ Not Implemented | |
 ## 17. Advanced
 | Flag | Rsync Description | FastSync Status | Notes |
 |------|-------------------|-----------------|-------|
 | `--stop-after=MINS` | Stop after N minutes | ❌ Not Implemented | |
 | `--stop-at=TIME` | Stop at specified time | ❌ Not Implemented | |
 | `--fsync` | Fsync every written file | ❌ Not Implemented | |
 | `--protocol=NUM` | Force older protocol version | ❌ Not Implemented | |
 | `--iconv=CONVERT_SPEC` | Charset conversion | ❌ Not Implemented | |
 | `--checksum-seed=NUM` | Set checksum seed | ❌ Not Implemented | |
 | `-s`, `--secluded-args` | Use protocol to send args | ❌ Not Implemented | |
 | `--no-OPTION` | Turn off implied option | ❌ Not Implemented | |
 ---
 ## Recommendations: Top Features to Implement Next
 Ranked by user demand, implementation complexity, and interoperability impact:
 | Priority | Feature | Effort | Impact |
 |----------|---------|--------|--------|
 | 1 | `--whole-file` / `-W` | Low | High — users expect opt-out of delta |
 | 2 | `--ignore-times` / `-I` | Low | Medium — useful for forcing re-transfer |
 | 3 | `--size-only` | Low | Medium — common migration scenario |
 | 4 | `--existing` / `--ignore-existing` | Low | Medium — common sync patterns |
 | 5 | `--remove-source-files` | Low | High — common for moves/backup |
 | 6 | `--delete-during` | Medium | High — performance improvement |
 | 7 | `--delay-updates` | Medium | High — atomic updates |
 | 8 | `--chmod` | Low | Medium — permission flexibility |
 | 9 | `--executability` / `-E` | Low | Low — simple flag |
 | 10 | `--skip-compress` | Low | Medium — performance tuning |
 ---
 ## FastSync-Specific Features (Not in rsync)
 | Feature | Description |
 |---------|-------------|
 | `-m` | Multithreaded pipeline (scanner/loader/sender) |
 | `-s` | Chunk serialization mode |
 | `-f` / `--sendfile` | Zero-copy sendfile() syscall (TCP only) |
 | `-c [level]` | zstd compression level (1-22) |
 | `--chunk-size` | Configurable chunk size |
 | `--tls` | TLS encryption (mutual auth) |
 | `--fastsync-server-path` | Path to fastsync-server binary |
 | `--server-host` / `--server-port` | Direct TCP connection |
 | Incremental sync | Skip unchanged files (size+mtime) |
 | Delta transfer | Block-level delta for changed files |
@@ -8,10 +8,13 @@
 #include "utils.h"
 #include <errno.h>
 #include <limits.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include "usage.c"
 #ifndef FASTSYNC_TEST_BUILD
 /* Parse environment variables for source/destination directories and save-to-disk flag. */
 static void parse_environment(const char** out_env_source, const char** out_env_dest,
                              bool* out_save_to_disk) {
@@ -22,19 +25,7 @@ static void parse_environment(const char** out_env_source, const char** out_env_
  if (env_save && (strcmp(env_save, "true") == 0 || strcmp(env_save, "1") == 0))
    *out_save_to_disk = true;
 }
-
+#endif
 /* Parse a string as a positive integer, returning true on success. */
 static bool parse_positive_int(const char* s, int* out_val) {
  if (!s || *s == '\0')
    return false;
  char* endptr;
  errno = 0;
  long val = strtol(s, &endptr, 10);
  if (errno != 0 || *endptr != '\0' || val <= 0 || val > INT_MAX)
    return false;
  *out_val = (int)val;
  return true;
 }
 /* Parse a string as a non-negative integer, returning true on success. */
 static bool parse_nonneg_int(const char* s, int* out_val) {
@@ -49,16 +40,62 @@ static bool parse_nonneg_int(const char* s, int* out_val) {
  return true;
 }
-static void print_usage(void);
+/* Parse a string as a positive integer, returning true on success. */
 static bool parse_positive_int(const char* s, int* out_val) {
  int temp;
  if (!parse_nonneg_int(s, &temp)) {
    return false;
  }
  if (temp == 0) {
    return false;
  }
  *out_val = temp;
  return true;
 }
 /* Duplicate a string argument into *dest, freeing the old value. Returns true on success, false on
 * failure. */
 static int set_string_option(char** dest, const char* value, const char* option_name) {
  char* dup = str_dup(value);
  if (!dup) {
    fprintf(stderr, "Error: memory allocation failed for %s\n", option_name);
    return -1;
  }
  free(*dest);
  *dest = dup;
  return 0;
 }
 /* Parse a string as a positive integer into *dest. Returns true on success, false on error. */
 static int set_positive_int_option(int* dest, const char* value, const char* option_name) {
  if (!parse_positive_int(value, dest)) {
    fprintf(stderr, "Error: %s must be a positive integer\n", option_name);
    return -1;
  }
  return 0;
 }
 /* Parse a string as a non-negative integer into *dest. Returns true on success, false on error. */
 static int set_nonneg_int_option(int* dest, const char* value, const char* option_name) {
  if (!parse_nonneg_int(value, dest)) {
    fprintf(stderr, "Error: %s must be a non-negative integer\n", option_name);
    return -1;
  }
  return 0;
 }
 static int read_patterns_from_file(const char* filepath, char*** patterns, int* count);
 /* Parse CLI arguments into config. Returns 0 on success, -1 on error, 1 for help/clean-exit. */
-static int parse_args(Config* config, int argc, char* argv[], int* positional_args,
+int parse_args(Config* config, int argc, char* argv[], int* positional_args,
               int* positional_count) {
  for (int i = 1; i < argc; i++) {
    if (strcmp(argv[i], "--help") == 0) {
      print_usage();
      return 1;
    } else if (strcmp(argv[i], "-V") == 0 || strcmp(argv[i], "--version") == 0) {
      printf("fastsync version %s\n", PROTOCOL_VERSION);
      return 1;
    } else if (strcmp(argv[i], "-a") == 0 || strcmp(argv[i], "--archive") == 0) {
      config->use_compression = true;
      config->use_multithreading = true;
@@ -67,8 +104,10 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
    } else if (strcmp(argv[i], "-n") == 0 || strcmp(argv[i], "--dry-run") == 0) {
      config->dry_run = true;
    } else if (strcmp(argv[i], "-p") == 0 && i + 1 < argc) {
-      if (!parse_positive_int(argv[++i], &config->ssh_port)) {
+      if (set_positive_int_option(&config->ssh_port, argv[++i], "-p") != 0)
-        fprintf(stderr, "Error: invalid --port/-p value: %s\n", argv[i]);
+        return -1;
      if (config->ssh_port > 65535) {
        log_message(LOG_LEVEL_ERROR, "SSH port must be 1-65535\n");
        return -1;
      }
    } else if (strcmp(argv[i], "--delete") == 0) {
@@ -100,21 +139,47 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
      }
      config->include_patterns[config->include_count++] = dup;
    } else if (strcmp(argv[i], "--max-size") == 0 && i + 1 < argc) {
-      config->max_size = strtoull(argv[++i], NULL, 10);
+      char* end;
      errno = 0;
      unsigned long long val = strtoull(argv[++i], &end, 10);
      if (errno != 0 || *end != '\0') {
        fprintf(stderr, "Error: --max-size must be a non-negative integer\n");
        return -1;
      }
      config->max_size = val;
    } else if (strcmp(argv[i], "--min-size") == 0 && i + 1 < argc) {
-      config->min_size = strtoull(argv[++i], NULL, 10);
+      char* end;
      errno = 0;
      unsigned long long val = strtoull(argv[++i], &end, 10);
      if (errno != 0 || *end != '\0') {
        fprintf(stderr, "Error: --min-size must be a non-negative integer\n");
        return -1;
      }
      config->min_size = val;
    } else if (strcmp(argv[i], "--incremental") == 0) {
      config->use_incremental = true;
    } else if (strcmp(argv[i], "--delta") == 0) {
      config->use_delta = true;
    } else if (strcmp(argv[i], "--delta-block") == 0 && i + 1 < argc) {
-      unsigned long long val = strtoull(argv[++i], NULL, 10);
+      char* end;
      errno = 0;
      unsigned long long val = strtoull(argv[++i], &end, 10);
      if (errno != 0 || *end != '\0') {
        fprintf(stderr, "Error: --delta-block must be a positive integer\n");
        return -1;
      }
      if (val >= DELTA_BLOCK_SIZE_MIN && val <= DELTA_BLOCK_SIZE_MAX)
        config->delta_block_size = (uint32_t)val;
      else
        fprintf(stderr, "Warning: --delta-block value %llu out of range, using default\n", val);
    } else if (strcmp(argv[i], "--delta-max") == 0 && i + 1 < argc) {
-      unsigned long long val = strtoull(argv[++i], NULL, 10);
+      char* end;
      errno = 0;
      unsigned long long val = strtoull(argv[++i], &end, 10);
      if (errno != 0 || *end != '\0') {
        fprintf(stderr, "Error: --delta-max must be a positive integer\n");
        return -1;
      }
      if (val >= DELTA_MIN_FILE_SIZE)
        config->delta_max_file_size = val;
      else
@@ -126,27 +191,21 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
        char* end_ptr;
        long level = strtol(argv[i + 1], &end_ptr, 10);
        if (*end_ptr == '\0') {
          if (level < 1 || level > 22) {
            fprintf(stderr, "Error: compression level must be 1-22\n");
            return -1;
          }
          config->compression_level = (int)level;
          log_message(LOG_LEVEL_INFO, "Set Compression level to %ld", level);
          i++;
        }
      }
    } else if (strcmp(argv[i], "--source-dir") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->send_directory, argv[++i], "--source-dir") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --source-dir\n");
        return -1;
      }
      free(config->send_directory);
      config->send_directory = dup;
    } else if (strcmp(argv[i], "--dest-dir") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->receive_root_directory, argv[++i], "--dest-dir") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --dest-dir\n");
        return -1;
      }
      free(config->receive_root_directory);
      config->receive_root_directory = dup;
    } else if (strcmp(argv[i], "--save-to-disk") == 0) {
      config->save_to_disk = true;
    } else if (strcmp(argv[i], "-M") == 0 || strcmp(argv[i], "--preserve") == 0) {
@@ -162,18 +221,17 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
      config->use_chunk_serialization = true;
      log_message(LOG_LEVEL_INFO, "Enabled Chunk Serialization");
    } else if (strcmp(argv[i], "--server-host") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->server_host, argv[++i], "--server-host") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --server-host\n");
        return -1;
      }
      free(config->server_host);
      config->server_host = dup;
    } else if (strcmp(argv[i], "--server-port") == 0 && i + 1 < argc) {
      if (!parse_positive_int(argv[++i], &config->server_port)) {
        fprintf(stderr, "Error: invalid --server-port value: %s\n", argv[i]);
        return -1;
      }
      if (config->server_port > 65535) {
        fprintf(stderr, "Error: server port must be 1-65535\n");
        return -1;
      }
    } else if (strcmp(argv[i], "--bwlimit") == 0 && i + 1 < argc) {
      char* end;
      errno = 0;
@@ -191,70 +249,47 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
    } else if (strcmp(argv[i], "--progress") == 0) {
      config->show_progress = true;
    } else if (strcmp(argv[i], "--chunk-size") == 0 && i + 1 < argc) {
-      unsigned long long val = strtoull(argv[++i], NULL, 10);
+      char* end;
-      if (val > 0)
+      errno = 0;
      unsigned long long val = strtoull(argv[++i], &end, 10);
      if (errno != 0 || *end != '\0' || val == 0) {
        fprintf(stderr, "Error: --chunk-size must be a positive integer\n");
        return -1;
      }
      config->chunk_size = val;
    } else if (strcmp(argv[i], "--tls") == 0) {
      config->use_tls = true;
    } else if (strcmp(argv[i], "--cert") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->tls_cert, argv[++i], "--cert") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --cert\n");
        return -1;
      }
      free(config->tls_cert);
      config->tls_cert = dup;
    } else if (strcmp(argv[i], "--key") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->tls_key, argv[++i], "--key") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --key\n");
        return -1;
      }
      free(config->tls_key);
      config->tls_key = dup;
    } else if (strcmp(argv[i], "--ca") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->tls_ca, argv[++i], "--ca") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --ca\n");
        return -1;
      }
      free(config->tls_ca);
      config->tls_ca = dup;
    } else if (strcmp(argv[i], "--timeout") == 0 && i + 1 < argc) {
-      int val;
+      if (set_positive_int_option(&config->timeout, argv[++i], "--timeout") != 0)
      if (!parse_positive_int(argv[++i], &val)) {
        fprintf(stderr, "Error: --timeout must be a positive integer\n");
        return -1;
      }
      config->timeout = val;
    } else if (strcmp(argv[i], "--contimeout") == 0 && i + 1 < argc) {
-      int val;
+      if (set_positive_int_option(&config->contimeout, argv[++i], "--contimeout") != 0)
      if (!parse_positive_int(argv[++i], &val)) {
        fprintf(stderr, "Error: --contimeout must be a positive integer\n");
        return -1;
      }
      config->contimeout = val;
    } else if (strcmp(argv[i], "-q") == 0 || strcmp(argv[i], "--quiet") == 0 ||
               strcmp(argv[i], "--silent") == 0) {
      config->quiet = true;
    } else if (strcmp(argv[i], "--backup") == 0) {
      config->backup = true;
    } else if (strcmp(argv[i], "--backup-dir") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->backup_dir, argv[++i], "--backup-dir") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --backup-dir\n");
        return -1;
      }
      free(config->backup_dir);
      config->backup_dir = dup;
    } else if (strcmp(argv[i], "--stats") == 0) {
      config->stats = true;
    } else if (strcmp(argv[i], "--max-depth") == 0 && i + 1 < argc) {
-      if (!parse_nonneg_int(argv[++i], &config->max_depth)) {
+      if (set_nonneg_int_option(&config->max_depth, argv[++i], "--max-depth") != 0)
        fprintf(stderr, "Error: --max-depth must be a non-negative integer\n");
        return -1;
      }
    } else if (strcmp(argv[i], "--log-file") == 0 && i + 1 < argc) {
      if (config->log_file) {
        fclose(config->log_file);
        config->log_file = NULL;
        log_set_file(NULL);
      }
      FILE* lf = fopen(argv[++i], "a");
      if (!lf) {
        fprintf(stderr, "Error: could not open log file '%s': %s\n", argv[i], strerror(errno));
@@ -262,13 +297,6 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
      }
      config->log_file = lf;
      log_set_file(lf);
    } else if (strcmp(argv[i], "--queue-size") == 0 && i + 1 < argc) {
      int val;
      if (!parse_positive_int(argv[++i], &val)) {
        fprintf(stderr, "Error: --queue-size must be a positive integer\n");
        return -1;
      }
      config->queue_size = val;
    } else if (strcmp(argv[i], "--exclude-from") == 0 && i + 1 < argc) {
      if (read_patterns_from_file(argv[++i], &config->exclude_patterns, &config->exclude_count) !=
          0)
@@ -280,13 +308,9 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
    } else if (strcmp(argv[i], "--partial") == 0) {
      config->partial = true;
    } else if (strcmp(argv[i], "--fastsync-server-path") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->fastsync_server_path, argv[++i], "--fastsync-server-path") !=
-      if (!dup) {
+          0)
        fprintf(stderr, "Error: memory allocation failed for --fastsync-server-path\n");
        return -1;
      }
      free(config->fastsync_server_path);
      config->fastsync_server_path = dup;
    } else if (strcmp(argv[i], "-v") == 0 || strcmp(argv[i], "--verbose") == 0) {
      set_log_level(LOG_LEVEL_DEBUG);
    } else if (strcmp(argv[i], "-l") == 0 || strcmp(argv[i], "--links") == 0) {
@@ -297,177 +321,26 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
      config->safe_links = true;
    } else if (strcmp(argv[i], "--copy-unsafe-links") == 0) {
      config->copy_unsafe_links = true;
    } else if (strcmp(argv[i], "-H") == 0 || strcmp(argv[i], "--hard-links") == 0) {
      config->preserve_hard_links = true;
    } else if (strcmp(argv[i], "-A") == 0 || strcmp(argv[i], "--acls") == 0) {
      config->preserve_acls = true;
    } else if (strcmp(argv[i], "-X") == 0 || strcmp(argv[i], "--xattrs") == 0) {
      config->preserve_xattrs = true;
    } else if (strcmp(argv[i], "-D") == 0 || strcmp(argv[i], "--devices") == 0) {
      config->preserve_devices = true;
    } else if (strcmp(argv[i], "-S") == 0 || strcmp(argv[i], "--sparse") == 0) {
      config->preserve_sparse = true;
    } else if (strcmp(argv[i], "-i") == 0 || strcmp(argv[i], "--itemize-changes") == 0) {
      config->itemize_changes = true;
    } else if (strcmp(argv[i], "--out-format") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->out_format);
      config->out_format = dup;
    } else if (strcmp(argv[i], "--info") == 0 && i + 1 < argc) {
      config->info_level = atoi(argv[++i]);
    } else if (strcmp(argv[i], "--debug") == 0 && i + 1 < argc) {
      config->debug_level = atoi(argv[++i]);
    } else if (strcmp(argv[i], "--list-only") == 0) {
      config->list_only = true;
    } else if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--human-readable") == 0) {
      config->human_readable = true;
    } else if (strcmp(argv[i], "-u") == 0 || strcmp(argv[i], "--update") == 0) {
      config->update = true;
    } else if (strcmp(argv[i], "--inplace") == 0) {
      config->inplace = true;
    } else if (strcmp(argv[i], "--append") == 0) {
      config->append = true;
    } else if (strcmp(argv[i], "--append-verify") == 0) {
      config->append_verify = true;
    } else if (strcmp(argv[i], "--delete-excluded") == 0) {
      config->delete_excluded = true;
    } else if (strcmp(argv[i], "--delete-after") == 0) {
      config->delete_after = true;
    } else if (strcmp(argv[i], "--max-delete") == 0 && i + 1 < argc) {
      int val;
      if (!parse_nonneg_int(argv[++i], &val)) {
        fprintf(stderr, "Error: --max-delete must be a non-negative integer\n");
        return -1;
      }
      config->max_delete = val;
    } else if (strcmp(argv[i], "--filter") == 0 && i + 1 < argc) {
      if (!config->filters)
        config->filters = array_list_create(free);
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      array_list_add(config->filters, dup);
    } else if (strcmp(argv[i], "--files-from") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->files_from);
      config->files_from = dup;
    } else if (strcmp(argv[i], "--cvs-exclude") == 0) {
      config->cvs_exclude = true;
    } else if (strcmp(argv[i], "--prune-empty-dirs") == 0) {
      config->prune_empty_dirs = true;
    } else if (strcmp(argv[i], "-R") == 0 || strcmp(argv[i], "--relative") == 0) {
      config->relative = true;
    } else if (strcmp(argv[i], "-e") == 0 || strcmp(argv[i], "--rsh") == 0) {
      if (i + 1 < argc) {
        char* dup = str_dup(argv[++i]);
        if (!dup)
          return -1;
        free(config->rsh_command);
        config->rsh_command = dup;
      } else {
        fprintf(stderr, "Error: -e/--rsh requires a command argument\n");
        return -1;
      }
    } else if (strcmp(argv[i], "--rsync-path") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->rsync_path);
      config->rsync_path = dup;
    } else if (strcmp(argv[i], "--temp-dir") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->temp_dir);
      config->temp_dir = dup;
    } else if (strcmp(argv[i], "--compare-dest") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->compare_dest);
      config->compare_dest = dup;
    } else if (strcmp(argv[i], "--copy-dest") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->copy_dest);
      config->copy_dest = dup;
    } else if (strcmp(argv[i], "--link-dest") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->link_dest);
      config->link_dest = dup;
    } else if (strcmp(argv[i], "--partial-dir") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->partial_dir, argv[++i], "--partial-dir") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --partial-dir\n");
        return -1;
      }
      free(config->partial_dir);
      config->partial_dir = dup;
    } else if (strcmp(argv[i], "--suffix") == 0 && i + 1 < argc) {
-      char* dup = str_dup(argv[++i]);
+      if (set_string_option(&config->suffix, argv[++i], "--suffix") != 0)
      if (!dup) {
        fprintf(stderr, "Error: memory allocation failed for --suffix\n");
        return -1;
      }
      free(config->suffix);
      config->suffix = dup;
    } else if (strcmp(argv[i], "--delete-before") == 0) {
      config->delete_before = true;
    } else if (strcmp(argv[i], "-T") == 0 && i + 1 < argc) {
-      int val;
+      if (set_positive_int_option(&config->timeout, argv[++i], "-T") != 0)
      if (!parse_positive_int(argv[++i], &val)) {
        fprintf(stderr, "Error: -T must be a positive integer\n");
        return -1;
      }
      config->timeout = val;
    } else if (strcmp(argv[i], "--address") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->address);
      config->address = dup;
    } else if (strcmp(argv[i], "--bind-address") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->bind_address);
      config->bind_address = dup;
    } else if (strcmp(argv[i], "--ipv6") == 0) {
      config->ipv6 = true;
    } else if (strcmp(argv[i], "--ipv4") == 0) {
      config->ipv4 = true;
    } else if (strcmp(argv[i], "--daemon") == 0) {
      config->daemon = true;
    } else if (strcmp(argv[i], "--config") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->daemon_config);
      config->daemon_config = dup;
    } else if (strcmp(argv[i], "--server") == 0) {
      config->server_mode = true;
    } else if (strcmp(argv[i], "--checksum") == 0) {
      config->checksum = true;
    } else if (strcmp(argv[i], "--compress-choice") == 0 && i + 1 < argc) {
      char* dup = str_dup(argv[++i]);
      if (!dup)
        return -1;
      free(config->compress_choice);
      config->compress_choice = dup;
    } else if (strcmp(argv[i], "--compress-level") == 0 && i + 1 < argc) {
-      int val;
+      if (set_positive_int_option(&config->compression_level, argv[++i], "--compress-level") != 0)
-      if (!parse_positive_int(argv[++i], &val)) {
+        return -1;
-        fprintf(stderr, "Error: --compress-level must be a positive integer\n");
+      if (config->compression_level < 1 || config->compression_level > 22) {
        fprintf(stderr, "Error: --compress-level must be between 1 and 22\n");
        return -1;
      }
      config->compression_level = val;
    } else if (argv[i][0] == '-') {
      fprintf(stderr, "Unknown option: %s\n", argv[i]);
      print_usage();
@@ -485,6 +358,7 @@ static int parse_args(Config* config, int argc, char* argv[], int* positional_ar
  return 0;
 }
 #ifndef FASTSYNC_TEST_BUILD
 /* Validate config after parsing. Returns true if valid. */
 static bool validate_config(const Config* config) {
  if (!config->send_directory || !config->receive_root_directory) {
@@ -525,115 +399,7 @@ static bool validate_config(const Config* config) {
  }
  return true;
 }
-
+#endif /* FASTSYNC_TEST_BUILD */
 static void print_usage(void) {
  printf("Usage:\n");
  printf("  fastsync [options] <source> <destination>\n");
  printf("  fastsync [options] --source-dir <src> --dest-dir <dst>\n");
  printf("\n");
  printf("Destination formats:\n");
  printf("  user@host:/path     SSH transport (rsync-style)\n");
  printf("  host:/path          SSH transport (current user)\n");
  printf("  /local/path         TCP transport (requires server on localhost:8080)\n");
  printf("\n");
  printf("Options:\n");
  printf("  -c [level]          Enable compression (level 1-22, default 5)\n");
  printf("  -z [level]          Alias for -c\n");
  printf("  -a, --archive       Archive mode (-c -m -M)\n");
  printf("  -n, --dry-run       Show what would be transferred\n");
  printf("  -p <port>           SSH port (default: 22)\n");
  printf("  --progress          Show transfer progress\n");
  printf("  --delete            Delete files on receiver not in source\n");
  printf("  --exclude <pattern> Exclude files matching pattern\n");
  printf("  --include <pattern> Only include files matching pattern\n");
  printf("  --exclude-from <file> Read exclude patterns from file\n");
  printf("  --include-from <file> Read include patterns from file\n");
  printf("  --max-size <n>      Skip files larger than n bytes\n");
  printf("  --min-size <n>      Skip files smaller than n bytes\n");
  printf("  --incremental       Skip files unchanged since last transfer\n");
  printf("  --delta             Delta transfer for changed files (requires --incremental)\n");
  printf("  --delta-block <n>   Delta block size in bytes (default: %d)\n",
         DELTA_BLOCK_SIZE_DEFAULT);
  printf("  --delta-max <n>     Max file size for delta transfer (default: %llu)\n",
         DELTA_MAX_FILE_SIZE);
  printf("  -m                  Enable multithreading\n");
  printf("  -s                  Enable chunk serialization\n");
  printf("  -f                  Enable sendfile (TCP only, not with -c or -s)\n");
  printf("  -v, --verbose       Enable debug logging\n");
  printf("  -M, --preserve      Preserve file metadata\n");
  printf("  --chunk-size <n>    Chunk size in bytes (default: %d)\n", DEFAULT_CHUNK_SIZE);
  printf("  --source-dir <path> Source directory\n");
  printf("  --dest-dir <path>   Destination directory\n");
  printf("  --save-to-disk      Write received files to disk\n");
  printf("  --server-host <ip>  Server IP address (default: 127.0.0.1)\n");
  printf("  --server-port <n>   Server port (default: 8080)\n");
  printf("  --bwlimit <KB/s>    Bandwidth limit in kilobytes per second\n");
  printf("  --tls               Enable TLS encryption\n");
  printf("  --cert <path>       TLS certificate file (PEM)\n");
  printf("  --key <path>        TLS private key file (PEM)\n");
  printf("  --ca <path>         TLS CA certificate file (PEM)\n");
  printf("  --timeout <sec>     I/O timeout in seconds (default: 30)\n");
  printf("  -T <sec>            Alias for --timeout\n");
  printf("  --contimeout <sec>  Connection timeout in seconds (default: 10)\n");
  printf("  --address <host>    Server hostname/IP to connect to\n");
  printf("  --bind-address <ip> Bind to specific local address\n");
  printf("  --ipv6              Prefer IPv6 connections\n");
  printf("  --ipv4              Prefer IPv4 connections\n");
  printf("  -q, --quiet         Suppress non-error output\n");
  printf("  --silent            Alias for --quiet\n");
  printf("  --backup            Backup existing files before overwriting\n");
  printf("  --backup-dir <dir>  Directory for backups (requires --backup)\n");
  printf("  --suffix <str>      Backup suffix (default: ~)\n");
  printf("  --stats             Print transfer statistics at end\n");
  printf("  --max-depth <n>     Maximum directory depth (0=unlimited)\n");
  printf("  --log-file <path>   Write log messages to file\n");
  printf("  --queue-size <n>    Queue capacity for multithreaded mode (default: 100)\n");
  printf("  --partial           Keep partial files on interrupted transfer\n");
  printf("  --partial-dir <dir> Directory for partial files\n");
  printf("  --fastsync-server-path <path>\n");
  printf("                      Path to fastsync-server on remote (default: fastsync-server)\n");
  printf("  -l, --links         Copy symlinks as symlinks\n");
  printf("  --copy-links        Transform symlinks into referent files\n");
  printf("  --safe-links        Skip symlinks that point outside transfer tree\n");
  printf("  --copy-unsafe-links  Only transform unsafe symlinks into referent files\n");
  printf("  -H, --hard-links    Preserve hard links\n");
  printf("  -A, --acls          Preserve ACLs\n");
  printf("  -X, --xattrs        Preserve extended attributes\n");
  printf("  -D, --devices       Preserve device files\n");
  printf("  -S, --sparse        Handle sparse files efficiently\n");
  printf("  -i, --itemize-changes  Show per-file change summary\n");
  printf("  --out-format <fmt>  Custom output format string\n");
  printf("  --info <flags>      Info verbosity level\n");
  printf("  --debug <flags>     Debug verbosity level\n");
  printf("  --list-only         List files without transferring\n");
  printf("  -h, --human-readable  Human-readable numbers\n");
  printf("  -u, --update        Skip files newer on destination\n");
  printf("  --inplace           Update files in-place (no temp+rename)\n");
  printf("  --append            Append data to shorter files\n");
  printf("  --append-verify     Append with verify\n");
  printf("  --delete-before     Delete before transfer\n");
  printf("  --delete-excluded   Also delete excluded files\n");
  printf("  --delete-after      Delete after transfer, not before\n");
  printf("  --max-delete <n>    Maximum number of files to delete\n");
  printf("  --filter <rule>     Add file filtering rule\n");
  printf("  --files-from <file> Read file list from file\n");
  printf("  --cvs-exclude       Auto-ignore CVS files\n");
  printf("  --prune-empty-dirs  Omit empty directories from transfer\n");
  printf("  -R, --relative      Use relative paths\n");
  printf("  -e, --rsh <cmd>     Specify remote shell\n");
  printf("  --rsync-path <path> Path to remote binary\n");
  printf("  --daemon            Run in daemon mode\n");
  printf("  --config <path>     Path to configuration file\n");
  printf("  --server            Run in server mode\n");
  printf("  --checksum          Skip files based on checksum, not mod-time/size\n");
  printf("  --compress-choice <alg>  Compression algorithm (default: zstd)\n");
  printf("  --compress-level <n>    Compression level (default: 5)\n");
  printf("  --temp-dir <dir>    Temporary directory for files\n");
  printf("  --compare-dest <dir>  Compare destination\n");
  printf("  --copy-dest <dir>   Copy destination\n");
  printf("  --link-dest <dir>   Link destination\n");
  printf("  --help              Show this help\n");
 }
 static int read_patterns_from_file(const char* filepath, char*** patterns, int* count) {
  FILE* fp = fopen(filepath, "r");
@@ -641,8 +407,10 @@ static int read_patterns_from_file(const char* filepath, char*** patterns, int*
    fprintf(stderr, "Error: could not open pattern file '%s': %s\n", filepath, strerror(errno));
    return -1;
  }
-  char line[4096];
+  char* line = NULL;
-  while (fgets(line, sizeof(line), fp)) {
+  size_t line_size = 0;
  ssize_t n;
  while ((n = getline(&line, &line_size, fp)) != -1) {
    char* p = line;
    while (*p == ' ' || *p == '\t')
      p++;
@@ -656,6 +424,7 @@ static int read_patterns_from_file(const char* filepath, char*** patterns, int*
    char** tmp = realloc(*patterns, (*count + 1) * sizeof(char*));
    if (!tmp) {
      fprintf(stderr, "Error: memory allocation failed for pattern file\n");
      free(line);
      fclose(fp);
      return -1;
    }
@@ -663,15 +432,18 @@ static int read_patterns_from_file(const char* filepath, char*** patterns, int*
    char* dup = str_dup(p);
    if (!dup) {
      fprintf(stderr, "Error: memory allocation failed for pattern file\n");
      free(line);
      fclose(fp);
      return -1;
    }
    (*patterns)[(*count)++] = dup;
  }
  free(line);
  fclose(fp);
  return 0;
 }
 #ifndef FASTSYNC_TEST_BUILD
 int main(int argc, char* argv[]) {
  const char* env_source = NULL;
  const char* env_dest = NULL;
@@ -777,3 +549,4 @@ cleanup:
  }
  return exit_code;
 }
 #endif /* FASTSYNC_TEST_BUILD */
@@ -34,7 +34,7 @@ static int send_dry_run_manifest(Config* config) {
      config->send_directory, config->use_metadata, config->chunk_size, config->exclude_patterns,
      config->exclude_count, config->include_patterns, config->include_count, config->max_size,
      config->min_size, config->max_depth, config->follow_symlinks, config->copy_links,
-      config->safe_links, config->copy_unsafe_links, config->checksum);
+      config->safe_links, config->copy_unsafe_links);
  if (!scanner)
    return -1;
  Chunk* chunk;
@@ -346,6 +346,7 @@ static int send_chunks_multithreaded(void* pipeline_context) {
    }
    if (send_chunk(client, current_chunk, context->config) != 0) {
      fprintf(stderr, "Error: unexpected error while sending chunk\n");
      chunk_destroy(current_chunk);
      client_disconnect(client);
      client_delete(client);
      mtx_lock(&context->mutex_progress);
@@ -374,8 +375,7 @@ static int scan_directory_multithreaded(void* pipeline_context) {
      context->config->exclude_patterns, context->config->exclude_count,
      context->config->include_patterns, context->config->include_count, context->config->max_size,
      context->config->min_size, context->config->max_depth, 4, context->config->follow_symlinks,
-      context->config->copy_links, context->config->safe_links, context->config->copy_unsafe_links,
+      context->config->copy_links, context->config->safe_links, context->config->copy_unsafe_links);
      context->config->checksum);
  Chunk* current_chunk;
  while ((current_chunk = parallel_scanner_next(scanner)) != NULL) {
@@ -385,13 +385,31 @@ static int scan_directory_multithreaded(void* pipeline_context) {
        const char* p = current_chunk->items[i]->path;
        if (*p == '/')
          p++;
-        array_list_add(context->manifest, str_dup(p));
+        char* manifest_entry = str_dup(p);
        if (!manifest_entry) {
          log_message(LOG_LEVEL_ERROR, "Failed to allocate manifest entry");
          mtx_unlock(&context->mutex_scanner);
          context->cancelled = true;
          cnd_broadcast(&context->condition_not_full_scanner);
          cnd_broadcast(&context->condition_not_empty_scanner);
          parallel_scanner_destroy(scanner);
          return thrd_error;
        }
        array_list_add(context->manifest, manifest_entry);
      }
      mtx_unlock(&context->mutex_scanner);
    }
-    queue_enqueue_multithreaded(context->queue_scanner, current_chunk, &context->mutex_scanner,
+    if (!queue_enqueue_multithreaded_cancel(
-                                &context->condition_not_empty_scanner,
+            context->queue_scanner, current_chunk, &context->mutex_scanner,
-                                &context->condition_not_full_scanner);
+            &context->condition_not_empty_scanner, &context->condition_not_full_scanner,
            &context->cancelled)) {
      chunk_destroy(current_chunk);
      context->cancelled = true;
      cnd_broadcast(&context->condition_not_full_scanner);
      cnd_broadcast(&context->condition_not_empty_scanner);
      parallel_scanner_destroy(scanner);
      return thrd_error;
    }
  }
  mtx_lock(&context->mutex_scanner);
  context->scanner_done = true;
@@ -427,9 +445,16 @@ static int load_files_multithreaded(void* pipeline_context) {
        }
      }
    }
-    queue_enqueue_multithreaded(context->queue_loader, chunk, &context->mutex_loader,
+    if (!queue_enqueue_multithreaded_cancel(context->queue_loader, chunk, &context->mutex_loader,
                                            &context->condition_not_empty_loader,
-                                &context->condition_not_full_loader);
+                                            &context->condition_not_full_loader,
                                            &context->cancelled)) {
      chunk_destroy(chunk);
      context->cancelled = true;
      cnd_broadcast(&context->condition_not_full_loader);
      cnd_broadcast(&context->condition_not_empty_loader);
      return thrd_error;
    }
  }
 }
@@ -487,16 +512,20 @@ int send_files(Config* config) {
    client = client_create();
    if (!client || !client_connect_tls(client, config->server_host, config->server_port,
                                       config->tls_cert, config->tls_key, config->tls_ca)) {
-      if (client)
+      if (client) {
        client_disconnect(client);
        client_delete(client);
      }
      fprintf(stderr, "Error: could not connect to server via TLS\n");
      return 1;
    }
  } else {
    client = client_create();
    if (!client || !client_connect(client, config->server_host, config->server_port)) {
-      if (client)
+      if (client) {
        client_disconnect(client);
        client_delete(client);
      }
      fprintf(stderr, "Error: could not connect to server\n");
      return 1;
    }
@@ -510,7 +539,7 @@ int send_files(Config* config) {
      config->send_directory, config->use_metadata, config->chunk_size, config->exclude_patterns,
      config->exclude_count, config->include_patterns, config->include_count, config->max_size,
      config->min_size, config->max_depth, config->follow_symlinks, config->copy_links,
-      config->safe_links, config->copy_unsafe_links, config->checksum);
+      config->safe_links, config->copy_unsafe_links);
  Chunk* current_chunk;
  unsigned long long total_bytes = 0;
  int total_files = 0;
@@ -526,7 +555,17 @@ int send_files(Config* config) {
        const char* p = current_chunk->items[i]->path;
        if (*p == '/')
          p++;
-        array_list_add(manifest, str_dup(p));
+        char* manifest_entry = str_dup(p);
        if (!manifest_entry) {
          log_message(LOG_LEVEL_ERROR, "Failed to allocate manifest entry");
          chunk_destroy(current_chunk);
          array_list_delete(manifest);
          directory_scanner_destroy(scanner);
          client_disconnect(client);
          client_delete(client);
          return 1;
        }
        array_list_add(manifest, manifest_entry);
      }
    }
    if (!config->use_sendfile) {
@@ -625,17 +664,42 @@ int send_files_multithreaded(Config* config) {
  if (config->use_delete)
    context->manifest = array_list_create(free);
-  thrd_t scanner, loader, sender, progress;
+  thrd_t scanner, loader, sender;
-  if (thrd_create(&scanner, scan_directory_multithreaded, context) != thrd_success ||
+  bool scanner_created = false;
-      thrd_create(&loader, load_files_multithreaded, context) != thrd_success ||
+  bool loader_created = false;
-      thrd_create(&sender, send_chunks_multithreaded, context) != thrd_success) {
+  bool sender_created = false;
  scanner_created = (thrd_create(&scanner, scan_directory_multithreaded, context) == thrd_success);
  if (scanner_created)
    loader_created = (thrd_create(&loader, load_files_multithreaded, context) == thrd_success);
  if (scanner_created && loader_created)
    sender_created = (thrd_create(&sender, send_chunks_multithreaded, context) == thrd_success);
  if (!scanner_created || !loader_created || !sender_created) {
    perror("Error creating threads.\n");
    context->cancelled = true;
    context->scanner_done = true;
    context->loader_done = true;
    context->sender_done = true;
    cnd_broadcast(&context->condition_not_full_scanner);
    cnd_broadcast(&context->condition_not_empty_scanner);
    cnd_broadcast(&context->condition_not_full_loader);
    cnd_broadcast(&context->condition_not_empty_loader);
    if (sender_created)
      thrd_join(sender, NULL);
    if (loader_created)
      thrd_join(loader, NULL);
    if (scanner_created)
      thrd_join(scanner, NULL);
    pipeline_context_sender_destroy(context);
    return 1;
  }
  thrd_t progress;
  bool progress_created = false;
  if (config->show_progress) {
-    if (thrd_create(&progress, progress_thread_fn, context) != thrd_success) {
+    progress_created = (thrd_create(&progress, progress_thread_fn, context) == thrd_success);
    if (!progress_created) {
      perror("Error creating progress thread.\n");
      /* Non-fatal; continue without progress reporting */
    }
@@ -646,7 +710,7 @@ int send_files_multithreaded(Config* config) {
  thrd_join(loader, NULL);
  thrd_join(sender, &sender_result);
-  if (config->show_progress) {
+  if (progress_created) {
    /* Signal progress thread to exit if it hasn't already */
    mtx_lock(&context->mutex_progress);
    context->sender_done = true;
@@ -27,10 +27,14 @@ static void dir_entry_destroy(void* item) {
 static DirEntry* dir_entry_create(const char* path, int depth) {
  DirEntry* de = malloc(sizeof(DirEntry));
-  if (de) {
+  if (!de)
    return NULL;
  de->path = str_dup(path);
-    de->depth = depth;
+  if (!de->path) {
    free(de);
    return NULL;
  }
  de->depth = depth;
  return de;
 }
@@ -40,7 +44,7 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
                                           int include_count, unsigned long long max_size,
                                           unsigned long long min_size, int max_depth,
                                           bool follow_symlinks, bool copy_links, bool safe_links,
-                                           bool copy_unsafe_links, bool checksum) {
+                                           bool copy_unsafe_links) {
  DirectoryScanner* scanner = malloc(sizeof(DirectoryScanner));
  if (scanner == NULL)
    return NULL;
@@ -61,8 +65,18 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
  scanner->copy_links = copy_links;
  scanner->safe_links = safe_links;
  scanner->copy_unsafe_links = copy_unsafe_links;
-  scanner->checksum = checksum;
+  DirEntry* root = dir_entry_create(root_directory, 0);
-  queue_enqueue(scanner->directories, dir_entry_create(root_directory, 0));
+  if (!root) {
    queue_destroy(scanner->directories);
    free(scanner);
    return NULL;
  }
  if (!queue_enqueue(scanner->directories, root)) {
    dir_entry_destroy(root);
    queue_destroy(scanner->directories);
    free(scanner);
    return NULL;
  }
  return scanner;
 }
@@ -277,7 +291,6 @@ typedef struct {
  bool copy_links;
  bool safe_links;
  bool copy_unsafe_links;
  bool checksum;
 } ParallelWorkerArg;
 static int parallel_worker_thread(void* arg) {
@@ -286,7 +299,7 @@ static int parallel_worker_thread(void* arg) {
    DirectoryScanner* ds = directory_scanner_create(
        wa->dirs[i], wa->use_metadata, wa->chunk_size, wa->exclude_patterns, wa->exclude_count,
        wa->include_patterns, wa->include_count, wa->max_size, wa->min_size, wa->max_depth,
-        wa->follow_symlinks, wa->copy_links, wa->safe_links, wa->copy_unsafe_links, wa->checksum);
+        wa->follow_symlinks, wa->copy_links, wa->safe_links, wa->copy_unsafe_links);
    Chunk* chunk;
    while ((chunk = directory_scanner_next(ds)) != NULL) {
      queue_enqueue_multithreaded(wa->ps->result_queue, chunk, &wa->ps->result_mutex,
@@ -314,7 +327,7 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
                                         int include_count, unsigned long long max_size,
                                         unsigned long long min_size, int max_depth,
                                         int num_threads, bool follow_symlinks, bool copy_links,
-                                         bool safe_links, bool copy_unsafe_links, bool checksum) {
+                                         bool safe_links, bool copy_unsafe_links) {
  ParallelScanner* ps = calloc(1, sizeof(ParallelScanner));
  if (!ps)
    return NULL;
@@ -323,9 +336,28 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
    free(ps);
    return NULL;
  }
-  if (mtx_init(&ps->result_mutex, mtx_plain) != thrd_success ||
+  int init = 0;
-      cnd_init(&ps->result_not_empty) != thrd_success ||
+  bool ok = true;
-      cnd_init(&ps->result_not_full) != thrd_success) {
+  if (mtx_init(&ps->result_mutex, mtx_plain) != thrd_success)
    ok = false;
  if (ok) {
    init++;
    if (cnd_init(&ps->result_not_empty) != thrd_success)
      ok = false;
  }
  if (ok) {
    // cppcheck-suppress unreadVariable
    init++;
    if (cnd_init(&ps->result_not_full) != thrd_success)
      ok = false;
  }
  if (!ok) {
    if (init >= 3)
      cnd_destroy(&ps->result_not_full);
    if (init >= 2)
      cnd_destroy(&ps->result_not_empty);
    if (init >= 1)
      mtx_destroy(&ps->result_mutex);
    queue_destroy(ps->result_queue);
    free(ps);
    return NULL;
@@ -528,7 +560,6 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
      wa->copy_links = copy_links;
      wa->safe_links = safe_links;
      wa->copy_unsafe_links = copy_unsafe_links;
      wa->checksum = checksum;
      start += count;
      if (thrd_create(&ps->threads[t], parallel_worker_thread, wa) != thrd_success) {
        for (int j = 0; j < count; j++)
@@ -564,6 +595,7 @@ void parallel_scanner_destroy(ParallelScanner* ps) {
    return;
  ps->done = true;
  cnd_signal(&ps->result_not_empty);
  cnd_broadcast(&ps->result_not_full);
  for (int i = 0; i < ps->num_threads; i++)
    thrd_join(ps->threads[i], NULL);
  free(ps->threads);
@@ -25,7 +25,6 @@ typedef struct {
  bool copy_links;
  bool safe_links;
  bool copy_unsafe_links;
  bool checksum;
 } DirectoryScanner;
 typedef struct {
@@ -46,7 +45,7 @@ DirectoryScanner* directory_scanner_create(const char* root_directory, bool use_
                                           int include_count, unsigned long long max_size,
                                           unsigned long long min_size, int max_depth,
                                           bool follow_symlinks, bool copy_links, bool safe_links,
-                                           bool copy_unsafe_links, bool checksum);
+                                           bool copy_unsafe_links);
 Chunk* directory_scanner_next(DirectoryScanner* scanner);
 void directory_scanner_destroy(DirectoryScanner* scanner);
@@ -56,7 +55,7 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
                                         int include_count, unsigned long long max_size,
                                         unsigned long long min_size, int max_depth,
                                         int num_threads, bool follow_symlinks, bool copy_links,
-                                         bool safe_links, bool copy_unsafe_links, bool checksum);
+                                         bool safe_links, bool copy_unsafe_links);
 Chunk* parallel_scanner_next(ParallelScanner* scanner);
 void parallel_scanner_destroy(ParallelScanner* scanner);
@@ -0,0 +1,73 @@
 #include "stdio.h"
 #include <delta.h>
 #include <chunk.h>
 static __attribute__((unused)) void print_usage() {
  printf("Usage:\n");
  printf("  fastsync [options] <source> <destination>\n");
  printf("  fastsync [options] --source-dir <src> --dest-dir <dst>\n");
  printf("\n");
  printf("Destination formats:\n");
  printf("  user@host:/path     SSH transport (rsync-style)\n");
  printf("  host:/path          SSH transport (current user)\n");
  printf("  /local/path         TCP transport (requires server on localhost:8080)\n");
  printf("\n");
  printf("Options:\n");
  printf("  -c [level]          Enable compression (level 1-22, default 5)\n");
  printf("  -z [level]          Alias for -c\n");
  printf("  -a, --archive       Archive mode (-c -m -M)\n");
  printf("  -n, --dry-run       Show what would be transferred\n");
  printf("  -p <port>           SSH port (default: 22)\n");
  printf("  --progress          Show transfer progress\n");
  printf("  --delete            Delete files on receiver not in source\n");
  printf("  --exclude <pattern> Exclude files matching pattern\n");
  printf("  --include <pattern> Only include files matching pattern\n");
  printf("  --exclude-from <file> Read exclude patterns from file\n");
  printf("  --include-from <file> Read include patterns from file\n");
  printf("  --max-size <n>      Skip files larger than n bytes\n");
  printf("  --min-size <n>      Skip files smaller than n bytes\n");
  printf("  --incremental       Skip files unchanged since last transfer\n");
  printf("  --delta             Delta transfer for changed files (requires --incremental)\n");
  printf("  --delta-block <n>   Delta block size in bytes (default: %d)\n",
         DELTA_BLOCK_SIZE_DEFAULT);
  printf("  --delta-max <n>     Max file size for delta transfer (default: %llu)\n",
         DELTA_MAX_FILE_SIZE);
  printf("  -m                  Enable multithreading\n");
  printf("  -s                  Enable chunk serialization\n");
  printf("  -f                  Enable sendfile (TCP only, not with -c or -s)\n");
  printf("  -v, --verbose       Enable debug logging\n");
  printf("  -M, --preserve      Preserve file metadata\n");
  printf("  --chunk-size <n>    Chunk size in bytes (default: %d)\n", DEFAULT_CHUNK_SIZE);
  printf("  --source-dir <path> Source directory\n");
  printf("  --dest-dir <path>   Destination directory\n");
  printf("  --save-to-disk      Write received files to disk\n");
  printf("  --server-host <ip>  Server IP address (default: 127.0.0.1)\n");
  printf("  --server-port <n>   Server port (default: 8080)\n");
  printf("  --bwlimit <KB/s>    Bandwidth limit in kilobytes per second\n");
  printf("  --tls               Enable TLS encryption\n");
  printf("  --cert <path>       TLS certificate file (PEM)\n");
  printf("  --key <path>        TLS private key file (PEM)\n");
  printf("  --ca <path>         TLS CA certificate file (PEM)\n");
  printf("  --timeout <sec>     I/O timeout in seconds (default: 30)\n");
  printf("  -T <sec>            Alias for --timeout\n");
  printf("  --contimeout <sec>  Connection timeout in seconds (default: 10)\n");
  printf("  --backup            Backup existing files before overwriting\n");
  printf("  --backup-dir <dir>  Directory for backups (requires --backup)\n");
  printf("  --suffix <str>      Backup suffix (default: ~)\n");
  printf("  --stats             Print transfer statistics at end\n");
  printf("  --max-depth <n>     Maximum directory depth (0=unlimited)\n");
  printf("  --log-file <path>   Write log messages to file\n");
  printf("  --partial           Keep partial files on interrupted transfer\n");
  printf("  --partial-dir <dir> Directory for partial files\n");
  printf("  --fastsync-server-path <path>\n");
  printf("                      Path to fastsync-server on remote (default: fastsync-server)\n");
  printf("  -l, --links         Copy symlinks as symlinks\n");
  printf("  --copy-links        Transform symlinks into referent files\n");
  printf("  --safe-links        Skip symlinks that point outside transfer tree\n");
  printf("  --copy-unsafe-links  Only transform unsafe symlinks into referent files\n");
  printf("  -S, --sparse        Handle sparse files efficiently\n");
  printf("  --inplace           Update files in-place (no temp+rename)\n");
  printf("  --compress-level <n>    Compression level (default: 5)\n");
  printf("  --help              Show this help\n");
  printf("  -V, --version       Show version\n");
 }
@@ -135,11 +135,27 @@ void handler(int file_descriptor) {
      return;
    }
    thrd_t receiver, writer;
-    if (thrd_create(&receiver, receive_thread, context) != thrd_success ||
+    bool receiver_created = false;
-        thrd_create(&writer, write_thread, context) != thrd_success) {
+    bool writer_created = false;
    receiver_created = (thrd_create(&receiver, receive_thread, context) == thrd_success);
    if (receiver_created)
      writer_created = (thrd_create(&writer, write_thread, context) == thrd_success);
    if (!receiver_created || !writer_created) {
      perror("Error creating Threads");
-      pipeline_context_receiver_destroy(context);
+      if (receiver_created) {
        mtx_lock(&context->mutex);
        context->cancelled = true;
        cnd_broadcast(&context->condition_not_full);
        cnd_broadcast(&context->condition_not_empty);
        mtx_unlock(&context->mutex);
        close(file_descriptor);
        thrd_join(receiver, NULL);
      } else {
        close(file_descriptor);
      }
      if (writer_created)
        thrd_join(writer, NULL);
      pipeline_context_receiver_destroy(context);
      return;
    }
    thrd_join(receiver, NULL);
@@ -1,12 +1,13 @@
 #include "compression.h"
 #include "data.h"
 #include "log.h"
-#include "stdlib.h"
+#include <stdlib.h>
-#include "string.h"
+#include <string.h>
 #include <strings.h>
-#include "zstd.h"
+#include <zstd.h>
 #define INITIAL_DECOMPRESS_BUF_SIZE (1024 * 1024)
 #define MAX_DECOMPRESSED_SIZE (100ULL * 1024 * 1024) /* 100 MB hard ceiling */
 static const char* SKIP_COMPRESSION_EXTENSIONS[] = {".jpg", ".jpeg", ".png", ".gif", ".mp4", ".mkv",
                                                    ".zip", ".gz",   ".xz",  ".zst", NULL};
@@ -84,6 +85,13 @@ Data* data_decompress(Data* compressed_data) {
    dst_size = compressed_data->size * 3;
    if (dst_size < INITIAL_DECOMPRESS_BUF_SIZE)
      dst_size = INITIAL_DECOMPRESS_BUF_SIZE;
    if (dst_size > MAX_DECOMPRESSED_SIZE)
      dst_size = MAX_DECOMPRESSED_SIZE;
  }
  if (dst_size > MAX_DECOMPRESSED_SIZE) {
    log_message(LOG_LEVEL_ERROR, "Declared decompressed size exceeds %llu bytes",
                (unsigned long long)MAX_DECOMPRESSED_SIZE);
    return NULL;
  }
  ZSTD_DCtx* dctx = ZSTD_createDCtx();
@@ -113,7 +121,16 @@ Data* data_decompress(Data* compressed_data) {
      return NULL;
    }
    if (ret > 0 && output.pos == output.size) {
      if (buf_size >= MAX_DECOMPRESSED_SIZE) {
        log_message(LOG_LEVEL_ERROR, "Decompressed data exceeds %llu bytes",
                    (unsigned long long)MAX_DECOMPRESSED_SIZE);
        ZSTD_freeDCtx(dctx);
        data_destroy(uncompressed_data);
        return NULL;
      }
      buf_size *= 2;
      if (buf_size > MAX_DECOMPRESSED_SIZE)
        buf_size = MAX_DECOMPRESSED_SIZE;
      void* new_data = realloc(uncompressed_data->data, buf_size);
      if (!new_data) {
        log_message(LOG_LEVEL_ERROR, "Failed to grow decompression buffer");
@@ -8,10 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
-Config* config_create(void) {
+static void config_set_defaults(Config* config) {
  Config* config = malloc(sizeof(Config));
  if (!config)
    return NULL;
  config->version = str_dup(PROTOCOL_VERSION);
  config->send_directory = NULL;
  config->receive_root_directory = NULL;
@@ -48,59 +45,27 @@ Config* config_create(void) {
  config->server_port = 8080;
  config->timeout = 30;
  config->contimeout = 10;
  config->quiet = false;
  config->backup = false;
  config->backup_dir = NULL;
  config->stats = false;
  config->max_depth = 0;
  config->log_file = NULL;
  config->queue_size = 100;
  config->follow_symlinks = false;
  config->partial = false;
  config->copy_links = false;
  config->safe_links = false;
  config->copy_unsafe_links = false;
  config->preserve_hard_links = false;
  config->preserve_acls = false;
  config->preserve_xattrs = false;
  config->preserve_devices = false;
  config->preserve_sparse = false;
  config->itemize_changes = false;
  config->out_format = NULL;
  config->info_level = 0;
  config->debug_level = 0;
  config->list_only = false;
  config->human_readable = false;
  config->update = false;
  config->inplace = false;
  config->append = false;
  config->append_verify = false;
  config->delete_excluded = false;
  config->delete_after = false;
  config->max_delete = 0;
  config->filters = NULL;
  config->files_from = NULL;
  config->cvs_exclude = false;
  config->prune_empty_dirs = false;
  config->relative = false;
  config->rsh_command = NULL;
  config->rsync_path = NULL;
  config->temp_dir = NULL;
  config->compare_dest = NULL;
  config->copy_dest = NULL;
  config->link_dest = NULL;
  config->partial_dir = NULL;
  config->suffix = NULL;
-  config->delete_before = false;
+}
-  config->address = NULL;
+
-  config->bind_address = NULL;
+Config* config_create(void) {
-  config->ipv6 = false;
+  Config* config = malloc(sizeof(Config));
-  config->ipv4 = false;
+  if (!config)
-  config->daemon = false;
+    return NULL;
-  config->daemon_config = NULL;
+  config_set_defaults(config);
  config->server_mode = false;
  config->checksum = false;
  config->compress_choice = NULL;
  return config;
 }
@@ -131,6 +96,8 @@ void config_parse_ssh_dest(Config* config) {
 }
 void config_delete(Config* config) {
  if (config == NULL)
    return;
  free(config->version);
  free(config->send_directory);
  free(config->receive_root_directory);
@@ -147,26 +114,22 @@ void config_delete(Config* config) {
  free(config->tls_ca);
  free(config->backup_dir);
  free(config->server_host);
  free(config->out_format);
  free(config->files_from);
  free(config->rsh_command);
  free(config->rsync_path);
  free(config->temp_dir);
  free(config->compare_dest);
  free(config->copy_dest);
  free(config->link_dest);
  free(config->partial_dir);
  free(config->suffix);
  free(config->address);
  free(config->bind_address);
  free(config->daemon_config);
  free(config->compress_choice);
  if (config->filters) {
    array_list_delete(config->filters);
  }
  free(config);
 }
 /* Wire format order (must match config_receive and be updated when PROTOCOL_VERSION bumps):
 * version, send_directory, receive_root_directory, save_to_disk, use_multithreading,
 * use_chunk_serialization, use_compression, use_metadata, compression_level, chunk_size,
 * use_sendfile, use_delete, use_incremental, use_delta, delta_block_size, delta_max_file_size,
 * backup, backup_dir, follow_symlinks, copy_links, safe_links, copy_unsafe_links,
 * obsolete metadata flags, preserve_sparse, obsolete transfer flags, inplace, obsolete delete
 * flags, obsolete path options, partial, partial_dir, suffix, obsolete checksum options, status
 *
 * Obsolete fields remain as zero/empty compatibility slots. They must be consumed in this order
 * until the protocol version is intentionally changed.
 */
 bool config_send(int file_descriptor, const Config* config) {
  if (!send_str(file_descriptor, config->version))
    return false;
@@ -196,7 +159,7 @@ bool config_send(int file_descriptor, const Config* config) {
    return false;
  if (!send_int(file_descriptor, config->use_delta))
    return false;
-  if (!send_int(file_descriptor, (int)config->delta_block_size))
+  if (!send_n_data(file_descriptor, &config->delta_block_size, sizeof(config->delta_block_size)))
    return false;
  if (!send_n_data(file_descriptor, &config->delta_max_file_size, sizeof(unsigned long long)))
    return false;
@@ -212,35 +175,36 @@ bool config_send(int file_descriptor, const Config* config) {
    return false;
  if (!send_int(file_descriptor, config->copy_unsafe_links))
    return false;
-  if (!send_int(file_descriptor, config->preserve_hard_links))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_acls))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_xattrs))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->preserve_devices))
+  if (!send_int(file_descriptor, 0))
    return false;
  if (!send_int(file_descriptor, config->preserve_sparse))
    return false;
-  if (!send_int(file_descriptor, config->update))
+  if (!send_int(file_descriptor, 0))
    return false;
  if (!send_int(file_descriptor, config->inplace))
    return false;
-  if (!send_int(file_descriptor, config->append))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->append_verify))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->delete_excluded))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->delete_after))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_n_data(file_descriptor, &config->max_delete, sizeof(config->max_delete)))
+  int obsolete_int = 0;
  if (!send_n_data(file_descriptor, &obsolete_int, sizeof(obsolete_int)))
    return false;
-  if (!send_int(file_descriptor, config->relative))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->prune_empty_dirs))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_str(file_descriptor, config->temp_dir ? config->temp_dir : ""))
+  if (!send_str(file_descriptor, ""))
    return false;
  if (!send_int(file_descriptor, config->partial))
    return false;
@@ -248,11 +212,11 @@ bool config_send(int file_descriptor, const Config* config) {
    return false;
  if (!send_str(file_descriptor, config->suffix ? config->suffix : ""))
    return false;
-  if (!send_int(file_descriptor, config->delete_before))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_int(file_descriptor, config->checksum))
+  if (!send_int(file_descriptor, 0))
    return false;
-  if (!send_str(file_descriptor, config->compress_choice ? config->compress_choice : ""))
+  if (!send_str(file_descriptor, ""))
    return false;
  Status status;
  if (!receive_status(file_descriptor, &status))
@@ -264,13 +228,16 @@ bool config_send(int file_descriptor, const Config* config) {
  return true;
 }
 /* Wire format order: see the comment above config_send. */
 Config* config_receive(int file_descriptor) {
  Config* config = (Config*)malloc(sizeof(Config));
  if (config == NULL)
    return NULL;
-  memset(config, 0, sizeof(*config));
+  config_set_defaults(config);
  free(config->version);
  config->version = receive_str(file_descriptor);
  if (!config->version) {
    free(config->server_host);
    free(config);
    return NULL;
  }
@@ -278,6 +245,7 @@ Config* config_receive(int file_descriptor) {
    fprintf(stderr, "Protocol version mismatch: client=%s, server=%s\n", config->version,
            PROTOCOL_VERSION);
    free(config->version);
    free(config->server_host);
    free(config);
    send_status(file_descriptor, STATUS_ERROR);
    return NULL;
@@ -285,6 +253,7 @@ Config* config_receive(int file_descriptor) {
  config->send_directory = receive_str(file_descriptor);
  if (!config->send_directory) {
    free(config->version);
    free(config->server_host);
    free(config);
    return NULL;
  }
@@ -292,6 +261,7 @@ Config* config_receive(int file_descriptor) {
  if (!config->receive_root_directory) {
    free(config->version);
    free(config->send_directory);
    free(config->server_host);
    free(config);
    return NULL;
  }
@@ -328,67 +298,10 @@ Config* config_receive(int file_descriptor) {
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->use_delta = tmp;
-  if (!receive_int(file_descriptor, &tmp))
+  if (!receive_n_data(file_descriptor, &config->delta_block_size, sizeof(config->delta_block_size)))
    goto error;
  config->delta_block_size = (uint32_t)tmp;
  if (!receive_n_data(file_descriptor, &config->delta_max_file_size, sizeof(unsigned long long)))
    goto error;
  config->show_progress = false;
  config->dry_run = false;
  config->ssh_port = 22;
  config->transport = TRANSPORT_TCP;
  config->ssh_destination = NULL;
  config->fastsync_server_path = NULL;
  config->exclude_patterns = NULL;
  config->exclude_count = 0;
  config->include_patterns = NULL;
  config->include_count = 0;
  config->max_size = 0;
  config->min_size = 0;
  config->use_tls = false;
  config->tls_cert = NULL;
  config->tls_key = NULL;
  config->tls_ca = NULL;
  config->timeout = 30;
  config->contimeout = 10;
  config->quiet = false;
  config->stats = false;
  config->max_depth = 0;
  config->log_file = NULL;
  config->queue_size = 100;
  config->follow_symlinks = false;
  config->copy_links = false;
  config->safe_links = false;
  config->copy_unsafe_links = false;
  config->preserve_hard_links = false;
  config->preserve_acls = false;
  config->preserve_xattrs = false;
  config->preserve_devices = false;
  config->preserve_sparse = false;
  config->itemize_changes = false;
  config->out_format = NULL;
  config->info_level = 0;
  config->debug_level = 0;
  config->list_only = false;
  config->human_readable = false;
  config->update = false;
  config->inplace = false;
  config->append = false;
  config->append_verify = false;
  config->delete_excluded = false;
  config->delete_after = false;
  config->max_delete = 0;
  config->filters = NULL;
  config->files_from = NULL;
  config->cvs_exclude = false;
  config->prune_empty_dirs = false;
  config->relative = false;
  config->rsh_command = NULL;
  config->rsync_path = NULL;
  config->temp_dir = NULL;
  config->compare_dest = NULL;
  config->copy_dest = NULL;
  config->link_dest = NULL;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->backup = tmp;
@@ -409,48 +322,39 @@ Config* config_receive(int file_descriptor) {
  config->copy_unsafe_links = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_hard_links = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_acls = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_xattrs = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_devices = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->preserve_sparse = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->update = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->inplace = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->append = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->append_verify = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->delete_excluded = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->delete_after = tmp;
  if (!receive_n_data(file_descriptor, &config->max_delete, sizeof(config->max_delete)))
    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->relative = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->prune_empty_dirs = tmp;
+  int obsolete_int = 0;
-  config->temp_dir = receive_str(file_descriptor);
+  if (!receive_n_data(file_descriptor, &obsolete_int, sizeof(obsolete_int)))
  if (config->temp_dir == NULL)
    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  char* obsolete_string = receive_str(file_descriptor);
  if (obsolete_string == NULL)
    goto error;
  free(obsolete_string);
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->partial = tmp;
@@ -462,22 +366,12 @@ Config* config_receive(int file_descriptor) {
    goto error;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
  config->delete_before = tmp;
  if (!receive_int(file_descriptor, &tmp))
    goto error;
-  config->checksum = tmp;
+  obsolete_string = receive_str(file_descriptor);
-  config->compress_choice = receive_str(file_descriptor);
+  if (obsolete_string == NULL)
  if (config->compress_choice == NULL)
    goto error;
-  config->address = NULL;
+  free(obsolete_string);
  config->bind_address = NULL;
  config->ipv6 = false;
  config->ipv4 = false;
  config->daemon = false;
  config->daemon_config = NULL;
  config->server_mode = false;
  config->server_host = str_dup("127.0.0.1");
  config->server_port = 8080;
  if (!send_status(file_descriptor, STATUS_OK))
    goto error;
  return config;
@@ -488,10 +382,8 @@ error:
  free(config->receive_root_directory);
  free(config->server_host);
  free(config->backup_dir);
  free(config->temp_dir);
  free(config->partial_dir);
  free(config->suffix);
  free(config->compress_choice);
  free(config);
  return NULL;
 }
@@ -1,7 +1,6 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 #include "array_list.h"
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -45,13 +44,11 @@ typedef struct Config {
  char* tls_ca;
  int timeout;
  int contimeout;
  bool quiet;
  bool backup;
  char* backup_dir;
  bool stats;
  int max_depth;
  FILE* log_file;
  int queue_size;
  bool follow_symlinks;
  bool partial;
@@ -60,46 +57,9 @@ typedef struct Config {
  bool safe_links;
  bool copy_unsafe_links;
  // Issue #121: Extended metadata preservation
  bool preserve_hard_links;
  bool preserve_acls;
  bool preserve_xattrs;
  bool preserve_devices;
  bool preserve_sparse;
  // Issue #122: Output/logging options
  bool itemize_changes;
  char* out_format;
  int info_level;
  int debug_level;
  bool list_only;
  bool human_readable;
  // Issue #127: Transfer modes
  bool update;
  bool inplace;
  bool append;
  bool append_verify;
  // Issue #128: Extended delete options
  bool delete_excluded;
  bool delete_after;
  int max_delete;
  // Issue #129: Advanced file selection
  ArrayList* filters;
  char* files_from;
  bool cvs_exclude;
  bool prune_empty_dirs;
  bool relative;
  // Issue #130: Remote shell/connection options
  char* rsh_command;
  char* rsync_path;
  char* temp_dir;
  char* compare_dest;
  char* copy_dest;
  char* link_dest;
  // PR #174: Partial transfer resumption
  char* partial_dir;
@@ -107,28 +67,10 @@ typedef struct Config {
  // PR #178: Backup versioning
  char* suffix;
  // PR #179: Delete policies
  bool delete_before;
  // PR #181: IPv6 and bind address
  char* address;
  char* bind_address;
  bool ipv6;
  bool ipv4;
  // PR #182: Daemon/server mode
  bool daemon;
  char* daemon_config;
  bool server_mode;
  // PR #183: Checksum comparison
  bool checksum;
  // PR #184: Compression algorithm negotiation
  char* compress_choice;
 } Config;
-#define PROTOCOL_VERSION "1.3.0"
+/* This version must be bumped whenever config_send / config_receive wire format changes. */
 #define PROTOCOL_VERSION "2.1.0"
 #define DEFAULT_CHUNK_SIZE (10 * 1024 * 1024)
 Config* config_create(void);
@@ -388,6 +388,10 @@ Delta* delta_deserialize(const Data* data) {
    if (type == DELTA_OP_BLOCK_MATCH) {
      if (pos + sizeof(uint32_t) * 3 > data->size) {
        for (uint32_t k = 0; k < i; k++) {
          if (delta->instructions[k].type == DELTA_INSTR_LITERAL)
            free(delta->instructions[k].literal.data);
        }
        free(delta->instructions);
        free(delta);
        return NULL;
@@ -426,6 +430,11 @@ Delta* delta_deserialize(const Data* data) {
      }
      delta->instructions[i].literal.data = malloc(lit_len);
      if (!delta->instructions[i].literal.data) {
        log_message(LOG_LEVEL_ERROR, "Failed to allocate %u bytes for literal data", lit_len);
        for (uint32_t k = 0; k < i; k++) {
          if (delta->instructions[k].type == DELTA_INSTR_LITERAL)
            free(delta->instructions[k].literal.data);
        }
        free(delta->instructions);
        free(delta);
        return NULL;
@@ -449,7 +458,8 @@ Delta* delta_deserialize(const Data* data) {
 void* delta_apply(const void* old_data, uint64_t old_size, const Delta* delta,
                  uint32_t block_size) {
-  if (!old_data || !delta)
+  if (!old_data || !delta || (delta->new_file_size > 0 && delta->instructions == NULL) ||
      (delta->instruction_count > 0 && block_size == 0))
    return NULL;
  void* output = malloc((size_t)delta->new_file_size);
@@ -463,10 +473,15 @@ void* delta_apply(const void* old_data, uint64_t old_size, const Delta* delta,
  for (uint32_t i = 0; i < delta->instruction_count; i++) {
    if (delta->instructions[i].type == DELTA_INSTR_BLOCK_MATCH) {
      uint64_t src_offset = (uint64_t)delta->instructions[i].match.block_index * block_size;
      if (src_offset > UINT64_MAX - delta->instructions[i].match.block_offset) {
        free(output);
        return NULL;
      }
      src_offset += delta->instructions[i].match.block_offset;
      uint32_t len = delta->instructions[i].match.length;
-      if (src_offset + len > old_size) {
+      if (src_offset > old_size || (uint64_t)len > old_size - src_offset ||
          out_pos > delta->new_file_size || (uint64_t)len > delta->new_file_size - out_pos) {
        free(output);
        return NULL;
      }
@@ -474,6 +489,10 @@ void* delta_apply(const void* old_data, uint64_t old_size, const Delta* delta,
      out_pos += len;
    } else {
      uint32_t len = delta->instructions[i].literal.length;
      if (out_pos > delta->new_file_size || (uint64_t)len > delta->new_file_size - out_pos) {
        free(output);
        return NULL;
      }
      memcpy(out + out_pos, delta->instructions[i].literal.data, len);
      out_pos += len;
    }
@@ -16,7 +16,6 @@
 #include "config.h"
 #include "data.h"
 #include "file.h"
 #include "log.h"
 #include "metadata.h"
 #include "protocol.h"
 #include "utils.h"
@@ -96,6 +95,9 @@ bool file_load_data(File* file) {
  size_t bytes_read = file_content_to_buffer(file);
  if (bytes_read != file->data->size) {
    log_message(LOG_LEVEL_ERROR, "Did not read expected amount of bytes from file");
    free(file->data->data);
    file->data->data = NULL;
    file->data->size = 0;
    return false;
  }
  return true;
@@ -15,28 +15,38 @@ void log_set_file(FILE* fp) {
  log_fp = fp;
 }
 static inline void write_message(FILE* dest_io, LogLevel log_level, struct tm t, const char* format,
                                 va_list args) {
  fprintf(dest_io, "%04d-%02d-%02d %02d:%02d:%02d [%s]: ", t.tm_year + 1900, t.tm_mon + 1,
          t.tm_mday, t.tm_hour, t.tm_min, t.tm_sec, log_level_strings[log_level]);
  vfprintf(dest_io, format, args);
  fprintf(dest_io, "\n");
 }
 void log_message(LogLevel log_level, const char* format, ...) {
  if (log_level < current_log_level)
    return;
  if (log_level < 0 || log_level >= (int)(sizeof(log_level_strings) / sizeof(log_level_strings[0])))
    return;
  time_t now = time(NULL);
-  const struct tm* t = localtime(&now);
+  struct tm t;
  if (!localtime_r(&now, &t))
    return;
-  fprintf(stderr, "%04d-%02d-%02d %02d:%02d:%02d [%s]: ", t->tm_year + 1900, t->tm_mon + 1,
+  FILE* dest_io = stdout;
-          t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, log_level_strings[log_level]);
+  if (log_level == LOG_LEVEL_ERROR) {
    dest_io = stderr;
  }
  va_list args;
  va_start(args, format);
-  vfprintf(stderr, format, args);
+  write_message(dest_io, log_level, t, format, args);
  va_end(args);
  fprintf(stderr, "\n");
  if (log_fp) {
    fprintf(log_fp, "%04d-%02d-%02d %02d:%02d:%02d [%s]: ", t->tm_year + 1900, t->tm_mon + 1,
            t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, log_level_strings[log_level]);
    va_start(args, format);
-    vfprintf(log_fp, format, args);
+    write_message(log_fp, log_level, t, format, args);
    va_end(args);
    fprintf(log_fp, "\n");
    fflush(log_fp);
  }
 }
@@ -26,19 +26,49 @@ PipelineContextSender* pipeline_context_sender_create(Config* config, Queue* que
  context->manifest = NULL;
  context->progress_bytes = 0;
  context->sender_done = false;
-  if (mtx_init(&context->mutex_scanner, mtx_plain) != thrd_success ||
+  context->cancelled = false;
-      cnd_init(&context->condition_not_full_scanner) != thrd_success ||
+  int init = 0;
-      cnd_init(&context->condition_not_empty_scanner) != thrd_success ||
+  if (mtx_init(&context->mutex_scanner, mtx_plain) != thrd_success)
-      mtx_init(&context->mutex_loader, mtx_plain) != thrd_success ||
+    goto fail;
-      cnd_init(&context->condition_not_full_loader) != thrd_success ||
+  init++;
-      mtx_init(&context->mutex_progress, mtx_plain) != thrd_success ||
+  if (cnd_init(&context->condition_not_full_scanner) != thrd_success)
-      cnd_init(&context->condition_not_empty_loader) != thrd_success) {
+    goto fail;
  init++;
  if (cnd_init(&context->condition_not_empty_scanner) != thrd_success)
    goto fail;
  init++;
  if (mtx_init(&context->mutex_loader, mtx_plain) != thrd_success)
    goto fail;
  init++;
  if (cnd_init(&context->condition_not_full_loader) != thrd_success)
    goto fail;
  init++;
  if (cnd_init(&context->condition_not_empty_loader) != thrd_success)
    goto fail;
  init++;
  if (mtx_init(&context->mutex_progress, mtx_plain) != thrd_success)
    goto fail;
  // cppcheck-suppress unreadVariable
  init++;
  return context;
 fail:
  perror("Error initializing synchronization objects");
  if (init >= 6)
    cnd_destroy(&context->condition_not_empty_loader);
  if (init >= 5)
    cnd_destroy(&context->condition_not_full_loader);
  if (init >= 4)
    mtx_destroy(&context->mutex_loader);
  if (init >= 3)
    cnd_destroy(&context->condition_not_empty_scanner);
  if (init >= 2)
    cnd_destroy(&context->condition_not_full_scanner);
  if (init >= 1)
    mtx_destroy(&context->mutex_scanner);
  free(context);
  return NULL;
 }
  return context;
 }
 void pipeline_context_sender_destroy(PipelineContextSender* context) {
  if (context->manifest) {
@@ -67,15 +97,31 @@ PipelineContextReceiver* pipeline_context_receiver_create(Config* config, Queue*
  context->file_descriptor = file_descriptor;
  context->ssl = ssl;
  context->receiver_done = false;
-  if (mtx_init(&context->mutex, mtx_plain) != thrd_success ||
+  context->cancelled = false;
-      cnd_init(&context->condition_not_full) != thrd_success ||
+  int init = 0;
-      cnd_init(&context->condition_not_empty) != thrd_success) {
+  if (mtx_init(&context->mutex, mtx_plain) != thrd_success)
    goto fail;
  init++;
  if (cnd_init(&context->condition_not_full) != thrd_success)
    goto fail;
  init++;
  if (cnd_init(&context->condition_not_empty) != thrd_success)
    goto fail;
  // cppcheck-suppress unreadVariable
  init++;
  return context;
 fail:
  perror("Error initializing synchronization objects");
  if (init >= 3)
    cnd_destroy(&context->condition_not_empty);
  if (init >= 2)
    cnd_destroy(&context->condition_not_full);
  if (init >= 1)
    mtx_destroy(&context->mutex);
  free(context);
  return NULL;
 }
  return context;
 }
 void pipeline_context_receiver_destroy(PipelineContextReceiver* context) {
  config_delete(context->config);
@@ -94,8 +140,13 @@ static bool receive_chunk_enqueue(int file_descriptor, PipelineContextReceiver*
  for (int i = 0; i < chunk->element_count; i++) {
    File* file = chunk->items[i];
    chunk->items[i] = NULL;
-    queue_enqueue_multithreaded(context->queue, file, &context->mutex,
+    if (!queue_enqueue_multithreaded_cancel(context->queue, file, &context->mutex,
-                                &context->condition_not_empty, &context->condition_not_full);
+                                            &context->condition_not_empty,
                                            &context->condition_not_full, &context->cancelled)) {
      file_destroy(file);
      chunk_destroy(chunk);
      return false;
    }
  }
  chunk_destroy(chunk);
  return true;
@@ -129,8 +180,12 @@ int receive_thread(void* pipeline_context) {
      if (!skipped) {
        if (file == NULL)
          return thrd_error;
-        queue_enqueue_multithreaded(context->queue, file, &context->mutex,
+        if (!queue_enqueue_multithreaded_cancel(
-                                    &context->condition_not_empty, &context->condition_not_full);
+                context->queue, file, &context->mutex, &context->condition_not_empty,
                &context->condition_not_full, &context->cancelled)) {
          file_destroy(file);
          return thrd_error;
        }
      }
    } else if (status == STATUS_CHUNK) {
      if (!receive_chunk_enqueue(file_descriptor, context))
@@ -166,8 +221,12 @@ int receive_thread(void* pipeline_context) {
    } else {
      File* file = file_receive(config, file_descriptor);
      if (file) {
-        queue_enqueue_multithreaded(context->queue, file, &context->mutex,
+        if (!queue_enqueue_multithreaded_cancel(
-                                    &context->condition_not_empty, &context->condition_not_full);
+                context->queue, file, &context->mutex, &context->condition_not_empty,
                &context->condition_not_full, &context->cancelled)) {
          file_destroy(file);
          return thrd_error;
        }
      } else {
        log_message(LOG_LEVEL_ERROR, "Failed to receive file");
        return thrd_error;
@@ -26,6 +26,7 @@ typedef struct {
  mtx_t mutex_progress;
  unsigned long long progress_bytes;
  bool sender_done;
  bool cancelled;
 } PipelineContextSender;
 typedef struct PipelineContextReceiver {
@@ -37,6 +38,7 @@ typedef struct PipelineContextReceiver {
  cnd_t condition_not_full;
  cnd_t condition_not_empty;
  bool receiver_done;
  bool cancelled;
 } PipelineContextReceiver;
 PipelineContextSender* pipeline_context_sender_create(Config* config, Queue* queue_scanner,
@@ -6,10 +6,10 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <threads.h>
 #include <time.h>
 #include <unistd.h>
 #define MAX_DATA_SIZE (100ULL * 1024 * 1024)          /* 100 MB max per data message */
 #define RECEIVE_TIMEOUT_SEC 60                        /* 60 second per-message timeout */
 #define MAX_CONNECTION_MEMORY (1024ULL * 1024 * 1024) /* 1 GB total per connection */
@@ -20,6 +20,8 @@ static __thread SSL* io_ssl;
 static unsigned long long io_bwlimit = 0;
 static long long bw_tokens = 0;
 static struct timespec bw_last_refill = {0, 0};
 static mtx_t bw_mutex;
 static once_flag bw_mutex_once = ONCE_FLAG_INIT;
 static __thread unsigned long long total_allocated_bytes = 0;
@@ -28,15 +30,24 @@ void io_set_fds(int read_fd, int write_fd) {
  io_write_fd = write_fd;
 }
 static void bw_mutex_init(void) {
  mtx_init(&bw_mutex, mtx_plain);
 }
 void io_set_bwlimit(unsigned long long bytes_per_sec) {
  call_once(&bw_mutex_once, bw_mutex_init);
  mtx_lock(&bw_mutex);
  io_bwlimit = bytes_per_sec;
  bw_tokens = (long long)io_bwlimit;
  clock_gettime(CLOCK_MONOTONIC, &bw_last_refill);
  mtx_unlock(&bw_mutex);
 }
 static void bw_throttle(size_t bytes_written) {
  if (io_bwlimit == 0)
    return;
  call_once(&bw_mutex_once, bw_mutex_init);
  mtx_lock(&bw_mutex);
  struct timespec now;
  clock_gettime(CLOCK_MONOTONIC, &now);
@@ -61,6 +72,7 @@ static void bw_throttle(size_t bytes_written) {
    bw_tokens = 0;
    clock_gettime(CLOCK_MONOTONIC, &bw_last_refill);
  }
  mtx_unlock(&bw_mutex);
 }
 void io_set_ssl(SSL* ssl) {
@@ -177,6 +189,8 @@ static const char* status_to_string(Status status) {
 }
 bool send_str(int file_descriptor, const char* data) {
  if (data == NULL)
    return false;
  size_t size = strlen(data);
  if (!send_n_data(file_descriptor, &size, sizeof(size_t)))
    return false;
@@ -221,9 +235,9 @@ Data* receive_data(int file_descriptor) {
  unsigned long long size = 0;
  if (!receive_n_data(file_descriptor, &size, sizeof(unsigned long long)))
    return NULL;
-  if (size > MAX_DATA_SIZE) {
+  if (size > MAX_DATA_PAYLOAD_SIZE) {
    log_message(LOG_LEVEL_ERROR, "Data size %llu exceeds maximum %llu", size,
-                (unsigned long long)MAX_DATA_SIZE);
+                (unsigned long long)MAX_DATA_PAYLOAD_SIZE);
    return NULL;
  }
  if (total_allocated_bytes + size > MAX_CONNECTION_MEMORY) {
@@ -103,6 +103,22 @@ bool queue_enqueue_multithreaded(Queue* queue, void* item, mtx_t* mutex, cnd_t*
  return ok;
 }
 bool queue_enqueue_multithreaded_cancel(Queue* queue, void* item, mtx_t* mutex,
                                        cnd_t* condition_not_empty, cnd_t* condition_not_full,
                                        const bool* cancelled) {
  mtx_lock(mutex);
  while (queue_is_full(queue) && (cancelled == NULL || !*cancelled))
    cnd_wait(condition_not_full, mutex);
  if (cancelled != NULL && *cancelled) {
    mtx_unlock(mutex);
    return false;
  }
  bool ok = queue_enqueue(queue, item);
  cnd_signal(condition_not_empty);
  mtx_unlock(mutex);
  return ok;
 }
 void* queue_dequeue(Queue* queue) {
  if (queue == NULL || queue_is_empty(queue)) {
    perror("ERROR: Could not dequeue from null or empty queue.");
@@ -20,6 +20,9 @@ bool queue_is_full(const Queue* queue);
 bool queue_enqueue(Queue* queue, void* item);
 bool queue_enqueue_multithreaded(Queue* queue, void* item, mtx_t* mutex, cnd_t* condition_not_empty,
                                 cnd_t* condition_not_full);
 bool queue_enqueue_multithreaded_cancel(Queue* queue, void* item, mtx_t* mutex,
                                        cnd_t* condition_not_empty, cnd_t* condition_not_full,
                                        const bool* cancelled);
 void* queue_dequeue(Queue* queue);
 void* queue_dequeue_multithreaded(Queue* queue, mtx_t* mutex, cnd_t* condition_not_empty,
                                  cnd_t* condition_not_full, const bool* other_thread_done);
@@ -10,11 +10,13 @@
 #include <unistd.h>
 bool mkdir_r(const char* path) {
-  char* path_duplicate = malloc(strlen(path) + 1);
+  size_t path_len = strlen(path);
  char* path_duplicate = malloc(path_len + 1);
  if (!path_duplicate)
    return false;
-  memcpy(path_duplicate, path, strlen(path) + 1);
+  memcpy(path_duplicate, path, path_len + 1);
-  char* path_current = (char*)malloc((strlen(path) + 2) * sizeof(char));
+  size_t capacity = path_len + 2;
  char* path_current = (char*)malloc(capacity * sizeof(char));
  if (!path_current) {
    free(path_duplicate);
    return false;
@@ -33,6 +35,10 @@ bool mkdir_r(const char* path) {
  bool ok = true;
  while (part != NULL) {
    size_t part_len = strlen(part);
    if ((size_t)(path_current_position - path_current) + part_len + 2 > capacity) {
      ok = false;
      break;
    }
    memcpy(path_current_position, part, part_len);
    path_current_position += part_len;
    path_current_position[0] = '/';
@@ -64,10 +70,18 @@ char* str_dup(const char* string) {
  return new_string;
 }
 /* Match a glob pattern against a string. Supported wildcards:
 *   ?      matches any single character except '/'.
 *   *      matches any sequence of characters within one path component (no '/').
 *   **     matches any sequence of characters, including '/' (cross-directory).
 *   slash-star-star-slash is treated as a cross-directory wildcard when it appears between
 * literals.
 */
 bool glob_match(const char* pattern, const char* str) {
  while (*pattern) {
    if (*pattern == '*') {
      if (*(pattern + 1) == '*') {
        /* globstar: match across directories */
        pattern += 2;
        if (*pattern == '\0')
          return true;
@@ -80,6 +94,7 @@ bool glob_match(const char* pattern, const char* str) {
        }
        return glob_match(pattern, str);
      }
      /* single *: match within one path component */
      pattern++;
      while (*str && *str != '/') {
        if (glob_match(pattern, str))
@@ -94,6 +109,7 @@ bool glob_match(const char* pattern, const char* str) {
      str++;
    } else {
      if (*pattern != *str) {
        /* allow literal / ** / rest to match any number of directories */
        if (*pattern == '/' && *(pattern + 1) == '*' && *(pattern + 2) == '*') {
          const char* rest = pattern + 3;
          if (*rest == '/')
@@ -238,7 +238,7 @@ class TestProgress:
        )
        assert result.returncode == 0, f"Exit {result.returncode}: {result.stderr[:100]}"
        output = result.stdout + result.stderr
-        assert len(output) >= 0
+        assert output, "--progress produced no output"
 class TestBandwidthLimit:
@@ -52,9 +52,11 @@ def _check_ssh():
        pass
 _check_ssh()
@pytest.fixture(scope="module", autouse=True)
 def setup_test_data():
    _check_ssh()
    if SSH_AVAILABLE:
        generate_test_files(SOURCE_DIR, full=False)
        clean_dir(DEST_DIR)
@@ -84,8 +86,12 @@ def _run_ssh_test(name, flags, expected_missing=None):
    return make_result(name, True, duration)
@pytest.mark.skipif(not SSH_AVAILABLE, reason="SSH to localhost not available")
 class TestSSHStandard:
    @pytest.fixture(autouse=True)
    def require_ssh(self):
        if not SSH_AVAILABLE:
            pytest.skip("SSH to localhost not available")
    def test_standard(self):
        r = _run_ssh_test("SSH (localhost)", [])
        assert r["status"] == "Success", r["error"]
@@ -119,8 +125,12 @@ class TestSSHStandard:
        assert r["status"] == "Success", r["error"]
@pytest.mark.skipif(not SSH_AVAILABLE, reason="SSH to localhost not available")
 class TestSSHFeatures:
    @pytest.fixture(autouse=True)
    def require_ssh(self):
        if not SSH_AVAILABLE:
            pytest.skip("SSH to localhost not available")
    def test_archive(self):
        r = _run_ssh_test("SSH Archive (-a)", ["-a"])
        assert r["status"] == "Success", r["error"]
@@ -6,6 +6,9 @@
 #include <string.h>
 #include <unistd.h>
 /* Declaration of parse_args from client_cli.c */
 int parse_args(Config* config, int argc, char* argv[], int* positional_args, int* positional_count);
 /* Test main() with --help flag (early return path, no server connection needed) */
 static void test_cli_help() {
  /* We can't easily call main() because it calls send_files which needs a server.
@@ -80,10 +83,225 @@ static void test_cli_exclude_patterns() {
  config_delete(cfg);
 }
 /* Test parse_args with --help returns 1 (clean exit) */
 static void test_parse_args_help() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "--help"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 2, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 1);
  config_delete(cfg);
 }
 /* Test parse_args with -V/--version returns 1 */
 static void test_parse_args_version() {
  Config* cfg = config_create();
  char* argv_short[] = {"fastsync", "-V"};
  char* argv_long[] = {"fastsync", "--version"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 2, argv_short, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 1);
  ret = parse_args(cfg, 2, argv_long, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 1);
  config_delete(cfg);
 }
 /* Test parse_args with valid port */
 static void test_parse_args_valid_port() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "-p", "2222", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 0);
  EXPECT_EQ_INT(cfg->ssh_port, 2222);
  EXPECT_EQ_INT(positional_count, 2);
  config_delete(cfg);
 }
 /* Test parse_args rejects port > 65535 */
 static void test_parse_args_invalid_port() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "-p", "99999", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, -1);
  config_delete(cfg);
 }
 /* Test parse_args rejects non-numeric port */
 static void test_parse_args_non_numeric_port() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "-p", "abc", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, -1);
  config_delete(cfg);
 }
 /* Test parse_args rejects server port > 65535 */
 static void test_parse_args_invalid_server_port() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "--server-port", "70000", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, -1);
  config_delete(cfg);
 }
 /* Test parse_args rejects invalid compression level */
 static void test_parse_args_invalid_compression_level() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "-c", "25", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, -1);
  config_delete(cfg);
 }
 /* Test parse_args accepts valid compression level */
 static void test_parse_args_valid_compression_level() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "-c", "10", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 5, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 0);
  EXPECT_EQ_INT(cfg->compression_level, 10);
  config_delete(cfg);
 }
 /* Test parse_args unknown option returns error */
 static void test_parse_args_unknown_option() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "--nonexistent", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 4, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, -1);
  config_delete(cfg);
 }
 /* Parsed-but-unimplemented options must fail instead of being silently accepted. */
 static void test_parse_args_rejects_unimplemented_options() {
  static const char* const options[] = {"-q",
                                        "--quiet",
                                        "--silent",
                                        "--queue-size",
                                        "-H",
                                        "--hard-links",
                                        "-A",
                                        "--acls",
                                        "-X",
                                        "--xattrs",
                                        "-D",
                                        "--devices",
                                        "-i",
                                        "--itemize-changes",
                                        "--out-format",
                                        "--info",
                                        "--debug",
                                        "--list-only",
                                        "-h",
                                        "--human-readable",
                                        "-u",
                                        "--update",
                                        "--append",
                                        "--append-verify",
                                        "--delete-excluded",
                                        "--delete-after",
                                        "--max-delete",
                                        "--filter",
                                        "--files-from",
                                        "--cvs-exclude",
                                        "--prune-empty-dirs",
                                        "-R",
                                        "--relative",
                                        "-e",
                                        "--rsh",
                                        "--rsync-path",
                                        "--temp-dir",
                                        "--compare-dest",
                                        "--copy-dest",
                                        "--link-dest",
                                        "--delete-before",
                                        "--address",
                                        "--bind-address",
                                        "--ipv6",
                                        "--ipv4",
                                        "--daemon",
                                        "--config",
                                        "--server",
                                        "--checksum",
                                        "--compress-choice"};
  for (size_t i = 0; i < sizeof(options) / sizeof(options[0]); i++) {
    Config* cfg = config_create();
    char* argv[] = {"fastsync", (char*)options[i], "dummy", "/src", "/dst"};
    int positional_args[2];
    int positional_count = 0;
    EXPECT_EQ_INT(parse_args(cfg, 5, argv, positional_args, &positional_count), -1);
    config_delete(cfg);
  }
 }
 /* Test parse_args with --archive flag */
 static void test_parse_args_archive() {
  Config* cfg = config_create();
  char* argv[] = {"fastsync", "--archive", "/src", "/dst"};
  int positional_args[2];
  int positional_count = 0;
  int ret = parse_args(cfg, 4, argv, positional_args, &positional_count);
  EXPECT_EQ_INT(ret, 0);
  EXPECT_TRUE(cfg->use_compression);
  EXPECT_TRUE(cfg->use_multithreading);
  EXPECT_TRUE(cfg->use_metadata);
  config_delete(cfg);
 }
 void test_client_cli() {
  test_cli_help();
  test_cli_archive_flags();
  test_cli_dry_run();
  test_cli_delete_flag();
  test_cli_exclude_patterns();
  test_parse_args_help();
  test_parse_args_version();
  test_parse_args_valid_port();
  test_parse_args_invalid_port();
  test_parse_args_non_numeric_port();
  test_parse_args_invalid_server_port();
  test_parse_args_invalid_compression_level();
  test_parse_args_valid_compression_level();
  test_parse_args_unknown_option();
  test_parse_args_rejects_unimplemented_options();
  test_parse_args_archive();
 }
@@ -323,6 +323,22 @@ static void test_large_file_delta() {
  free(new_data);
 }
 static void test_delta_apply_rejects_output_overflow() {
  uint8_t old_data[8] = {0};
  uint8_t literal_data[2] = {'x', 'y'};
  DeltaInstruction instruction = {
      .type = DELTA_INSTR_LITERAL,
      .literal = {.data = literal_data, .length = sizeof(literal_data)},
  };
  Delta delta = {
      .new_file_size = 1,
      .instruction_count = 1,
      .instructions = &instruction,
  };
  EXPECT_TRUE(delta_apply(old_data, sizeof(old_data), &delta, 1) == NULL);
 }
 void test_delta() {
  test_adler32_basic();
  test_adler32_different_data();
@@ -338,4 +354,5 @@ void test_delta() {
  test_should_attempt();
  test_is_worthwhile();
  test_large_file_delta();
  test_delta_apply_rejects_output_overflow();
 }
@@ -19,7 +19,7 @@ static void test_scanner_single_file() {
  create_test_file(file1, content1);
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -48,7 +48,7 @@ static void test_scanner_multiple_files() {
  create_test_file(file2, content2);
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  const Chunk* chunk = directory_scanner_next(scanner);
@@ -88,7 +88,7 @@ static void test_scanner_subdirectory() {
  create_test_file(sub_file, content);
  DirectoryScanner* scanner = directory_scanner_create((char*)root, false, 0, NULL, 0, NULL, 0, 0,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  int total_files = 0;
@@ -112,7 +112,7 @@ static void test_scanner_empty_directory() {
  EXPECT_EQ_INT(mkdir(dir, 0755), 0);
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  const Chunk* chunk = directory_scanner_next(scanner);
@@ -136,7 +136,7 @@ static void test_scanner_exclude_pattern() {
  char* exclude[] = {"*.tmp"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, NULL, 0, 0,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -169,7 +169,7 @@ static void test_scanner_exclude_subdirectory() {
  char* exclude[] = {"*.tmp"};
  DirectoryScanner* scanner = directory_scanner_create((char*)root, false, 0, exclude, 1, NULL, 0,
-                                                       0, 0, 0, false, false, false, false, false);
+                                                       0, 0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  int total = 0;
@@ -207,7 +207,7 @@ static void test_scanner_include_and_exclude() {
  char* exclude[] = {"*.bak"};
  char* include[] = {"*.txt", "*.log"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, include, 2,
-                                                       0, 0, 0, false, false, false, false, false);
+                                                       0, 0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -244,7 +244,7 @@ static void test_scanner_max_size() {
  /* max_size = 10 — only files <= 10 bytes */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 10,
-                                                       0, 0, false, false, false, false, false);
+                                                       0, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -272,7 +272,7 @@ static void test_scanner_min_size() {
  /* min_size = 1 — only files >= 1 byte */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 1,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -302,7 +302,7 @@ static void test_scanner_size_range() {
  /* Only files between 3 and 20 bytes */
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 20,
-                                                       3, 0, false, false, false, false, false);
+                                                       3, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -338,7 +338,7 @@ static void test_scanner_mixed_patterns() {
  char* exclude[] = {"*.bak"};
  char* include[] = {"*.txt"};
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, exclude, 1, include, 1,
-                                                       10, 3, 0, false, false, false, false, false);
+                                                       10, 3, 0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
@@ -369,7 +369,7 @@ static void test_scanner_no_patterns() {
  create_test_file(f2, "second");
  DirectoryScanner* scanner = directory_scanner_create((char*)dir, false, 0, NULL, 0, NULL, 0, 0, 0,
-                                                       0, false, false, false, false, false);
+                                                       0, false, false, false, false);
  EXPECT_NOT_NULL(scanner);
  Chunk* chunk = directory_scanner_next(scanner);
Author	SHA1	Message	Date
TapTap	75040103d3	Merge pull request 'Remove unimplemented CLI options' (#209 ) from feat/remove-unimplemented-cli-options into evaluation-of-codebase-by-human CI / lint (pull_request) Successful in 25s Details CI / sanitizers (address) (pull_request) Successful in 35s Details CI / sanitizers (undefined) (pull_request) Successful in 35s Details CI / fuzz-build (pull_request) Successful in 13s Details CI / coverage (pull_request) Successful in 31s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details Reviewed-on: #209	2026-08-11 21:17:52 +02:00
TapTap	852e47a143	Satisfy cppcheck CLI and logger checks CI / lint (pull_request) Successful in 25s Details CI / sanitizers (address) (pull_request) Successful in 35s Details CI / sanitizers (undefined) (pull_request) Successful in 35s Details CI / fuzz-build (pull_request) Successful in 14s Details CI / coverage (pull_request) Successful in 31s Details CI / build-and-test (pull_request) Successful in 1m14s Details CI / valgrind (pull_request) Successful in 32s Details	2026-08-11 21:14:56 +02:00
TapTap	679e389ba6	Fix va_list cleanup in logger CI / lint (pull_request) Failing after 25s Details CI / build-and-test (pull_request) Has been skipped Details CI / sanitizers (address) (pull_request) Has been skipped Details CI / sanitizers (undefined) (pull_request) Has been skipped Details CI / fuzz-build (pull_request) Has been skipped Details CI / coverage (pull_request) Has been skipped Details CI / valgrind (pull_request) Has been skipped Details	2026-08-11 21:12:00 +02:00
TapTap	2e00fc31f2	Format CLI option test table CI / lint (pull_request) Failing after 25s Details CI / build-and-test (pull_request) Has been skipped Details CI / sanitizers (address) (pull_request) Has been skipped Details CI / sanitizers (undefined) (pull_request) Has been skipped Details CI / fuzz-build (pull_request) Has been skipped Details CI / coverage (pull_request) Has been skipped Details CI / valgrind (pull_request) Has been skipped Details	2026-08-11 21:08:54 +02:00
TapTap	d146e1bb7c	Remove unimplemented CLI options CI / lint (pull_request) Failing after 3s Details CI / build-and-test (pull_request) Has been skipped Details CI / sanitizers (address) (pull_request) Has been skipped Details CI / sanitizers (undefined) (pull_request) Has been skipped Details CI / fuzz-build (pull_request) Has been skipped Details CI / coverage (pull_request) Has been skipped Details CI / valgrind (pull_request) Has been skipped Details	2026-08-11 20:59:06 +02:00
TapTap	09fca8d931	start of human refactoring	2026-08-11 20:26:15 +02:00
TapTap	cb671bade0	Merge pull request 'fix: validate delta output and integration test skips' (#207 ) from fix/triage-delta-validation into dev Reviewed-on: #207	2026-08-08 20:17:38 +02:00
TapTap	4feb75957a	fix: validate delta output and integration test skips CI / lint (pull_request) Successful in 24s Details CI / sanitizers (address) (pull_request) Successful in 37s Details CI / sanitizers (undefined) (pull_request) Successful in 36s Details CI / fuzz-build (pull_request) Successful in 13s Details CI / coverage (pull_request) Successful in 30s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details	2026-08-08 20:09:06 +02:00
TapTap	d529360c01	Merge pull request 'refactor: extract CLI parser helpers, fix validation bugs' (#200 ) from refactor/cli-parser-helpers into dev Reviewed-on: #200	2026-08-08 20:02:09 +02:00
TapTap	8743d7f522	fix: address PR #200 review issues CI / lint (pull_request) Successful in 35s Details CI / sanitizers (undefined) (pull_request) Successful in 39s Details CI / fuzz-build (pull_request) Successful in 12s Details CI / sanitizers (address) (pull_request) Successful in 55s Details CI / coverage (pull_request) Successful in 30s Details CI / valgrind (pull_request) Successful in 32s Details CI / build-and-test (pull_request) Successful in 1m34s Details - Fix memory leak in delta_deserialize() on BLOCK_MATCH error path - Fix memory leak on malloc failure for literal data - Add port range validation (1-65535) for -p/--port and --server-port - Restore -V/--version flag with usage text - Use MAX_DATA_PAYLOAD_SIZE consistently (remove local MAX_DATA_SIZE) - Fix integer truncation in config_send/config_receive for delta_block_size - Add log messages for malloc failures - Extract config_set_defaults() helper to eliminate duplication - Add 10 new CLI tests for argument parsing	2026-08-08 20:01:48 +02:00
TapTap	05a74770ca	fix: address PR #200 review issues CI / lint (pull_request) Successful in 22s Details CI / sanitizers (address) (pull_request) Successful in 37s Details CI / sanitizers (undefined) (pull_request) Successful in 36s Details CI / fuzz-build (pull_request) Successful in 13s Details CI / coverage (pull_request) Successful in 31s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details - Restore PROTOCOL_VERSION to a forward-compatible 2.1.0 and document wire format - Add NULL guard to config_delete - Add pipeline cancellation flag and cancellation-aware queue helper - Join running threads before destroying pipeline contexts on creation failure - Fix NULL dereference and memory leaks in manifest/chunk handling - Fix TLS/TCP socket fd leak on connect error paths - Add compression-level range validation (1-22) - Close previous log file before opening a new one - Use getline for unbounded pattern-file lines - Fix thread-unsafe localtime() and add log level bounds check - Fix file_load_data to clean up data on read size mismatch - Add hard ceiling to decompression buffer growth - Fix mkdir_r bounds check and restore glob comments - Add send_str NULL guard and mutex-protect bandwidth limiter - Update AGENTS.md for per-thread io_ssl contract	2026-08-02 09:34:54 +02:00
TapTap	98cb8e212e	Merge pull request 'docs: rsync feature compatibility matrix' (#199 ) from docs/rsync-compat into dev Reviewed-on: #199	2026-08-02 09:20:37 +02:00
TapTap	dd11f70043	docs: fix review issues in rsync compatibility matrix CI / lint (pull_request) Successful in 2m19s Details CI / sanitizers (address) (pull_request) Successful in 37s Details CI / sanitizers (undefined) (pull_request) Successful in 38s Details CI / fuzz-build (pull_request) Successful in 13s Details CI / coverage (pull_request) Successful in 31s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details - Fix -l/--links: mark as Partial (symlink targets not transmitted) - Fix -p/--perms: mark as Alt Arg (-p means SSH port, not perms) - Fix -c/--checksum: mark as Alt Arg (-c means compression) - Fix --address note: correct config field name - Remove --whole-file duplicate (Section 5 and 11) - Remove --secluded-args duplicate (Section 15 and 17) - Fix --skip-compress note: clarify hardcoded, not user-configurable - Fix --block-size note: clarify delta transfer, not checksum blocks - Recount summary totals: 39/5/30/62 = 136 total	2026-08-02 09:14:35 +02:00
TapTap	0b68974b42	docs: add 🔀 Alt Arg status for features with different flag semantics CI / lint (pull_request) Successful in 2m19s Details CI / sanitizers (address) (pull_request) Successful in 36s Details CI / sanitizers (undefined) (pull_request) Successful in 35s Details CI / fuzz-build (pull_request) Successful in 14s Details CI / coverage (pull_request) Successful in 32s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details	2026-08-02 09:01:11 +02:00
TapTap	df41e8bd06	docs: add rsync feature compatibility matrix	2026-08-02 09:01:11 +02:00
TapTap	1064ae6c19	fix: address PR review issues in client_cli.c CI / lint (pull_request) Successful in 23s Details CI / sanitizers (address) (pull_request) Successful in 36s Details CI / sanitizers (undefined) (pull_request) Successful in 36s Details CI / fuzz-build (pull_request) Successful in 13s Details CI / coverage (pull_request) Successful in 32s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details - Fix FILE* leak when --log-file specified multiple times - Add strtoull endptr validation for --delta-block/--delta-max - Add range validation (1-22) for -c compression level	2026-08-01 18:42:02 +02:00
TapTap	bf91c5b588	merge: resolve conflict with dev, apply helpers to new options CI / lint (pull_request) Successful in 23s Details CI / sanitizers (address) (pull_request) Successful in 35s Details CI / sanitizers (undefined) (pull_request) Successful in 36s Details CI / fuzz-build (pull_request) Successful in 14s Details CI / coverage (pull_request) Successful in 31s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details	2026-08-01 18:14:55 +02:00
TapTap	5eaea9d92e	refactor: extract CLI parser helpers, fix validation bugs CI / lint (pull_request) Successful in 16s Details CI / sanitizers (undefined) (pull_request) Successful in 37s Details CI / sanitizers (address) (pull_request) Successful in 39s Details CI / fuzz-build (pull_request) Successful in 14s Details CI / coverage (pull_request) Successful in 32s Details CI / build-and-test (pull_request) Successful in 1m15s Details CI / valgrind (pull_request) Successful in 33s Details - Add set_string_option(), set_positive_int_option(), set_nonneg_int_option() helpers to eliminate duplicated alloc/free/assign patterns - Replace 14 string-option branches with set_string_option() calls - Replace 7 integer-option branches with set_positive/nonneg_int_option() - Fix --info/--debug: replace atoi() with validated parse - Fix --max-size/--min-size: add strtoull() error checking - Fix --chunk-size: validate input with error message on failure	2026-08-01 18:12:41 +02:00
TapTap	9d67fcbf92	Merge pull request 'Batch fix: security, bugs, quality, and features (v2)' (#198 ) from integration/all-fixes-v2 into dev	2026-07-30 19:38:26 +02:00