fix: features and enhancements — issues #70, #36, #34, #33, #32, #57, #40, #37

src/shared/config.c

@@ -42,6 +42,8 @@ Config* config_create(char* version, char* send_directory, char* receive_directo
   config->delta_block_size = DELTA_BLOCK_SIZE_DEFAULT;
   config->delta_max_file_size = DELTA_MAX_FILE_SIZE;
   config->use_tls = false;
+  config->partial = false;
+  config->follow_symlinks = false;
   config->tls_cert = NULL;
   config->tls_key = NULL;
   config->tls_ca = NULL;
@@ -218,6 +220,8 @@ Config* config_receive(int file_descriptor) {
   config->max_size = 0;
   config->min_size = 0;
   config->use_tls = false;
+  config->partial = false;
+  config->follow_symlinks = false;
   config->tls_cert = NULL;
   config->tls_key = NULL;
   config->tls_ca = NULL;

src/shared/config.h

@@ -35,6 +35,8 @@ typedef struct Config {
   uint32_t delta_block_size;
   unsigned long long delta_max_file_size;
   bool use_tls;
+  bool partial;
+  bool follow_symlinks;
   char* server_host;
   int server_port;
   char* tls_cert;

src/shared/file.c

@@ -155,6 +155,49 @@ static void* old_data_from_path(const char* full_path, unsigned long long old_si
   return data;
 }
 
+/* Helper: receive data + optionally decompress + store in a new File.
+ * On success returns the File (caller owns it). On failure sends
+ * STATUS_ERROR on fd and returns NULL. */
+static File* receive_file_data(int fd, const Config* config, const char* check_path) {
+  File* file = file_create(check_path);
+  if (!file) {
+    send_status(fd, STATUS_ERROR);
+    return NULL;
+  }
+
+  if (config->use_metadata) {
+    int meta_ok = 1;
+    file->metadata = metadata_receive(fd, &meta_ok);
+    if (!meta_ok) {
+      file_destroy(file);
+      send_status(fd, STATUS_ERROR);
+      return NULL;
+    }
+  }
+
+  Data* file_data = receive_data(fd);
+  if (!file_data) {
+    file_destroy(file);
+    send_status(fd, STATUS_ERROR);
+    return NULL;
+  }
+
+  if (config->use_compression) {
+    Data* uncompressed = data_decompress(file_data);
+    data_destroy(file_data);
+    if (!uncompressed) {
+      file_destroy(file);
+      send_status(fd, STATUS_ERROR);
+      return NULL;
+    }
+    file_data = uncompressed;
+  }
+
+  data_destroy(file->data);
+  file->data = file_data;
+  return file;
+}
+
 static File* receive_delta_file(int fd, const Config* config, const char* check_path,
                                 void* old_data, unsigned long long old_size) {
   if (!old_data)
@@ -264,43 +307,7 @@ static File* receive_delta_file(int fd, const Config* config, const char* check_
     delta_signature_destroy(sig);
     free(old_data);
 
-    File* file = file_create(check_path);
-    if (!file) {
-      send_status(fd, STATUS_ERROR);
-      return NULL;
-    }
-
-    if (config->use_metadata) {
-      int meta_ok = 1;
-      file->metadata = metadata_receive(fd, &meta_ok);
-      if (!meta_ok) {
-        file_destroy(file);
-        send_status(fd, STATUS_ERROR);
-        return NULL;
-      }
-    }
-
-    Data* file_data = receive_data(fd);
-    if (file_data == NULL) {
-      file_destroy(file);
-      send_status(fd, STATUS_ERROR);
-      return NULL;
-    }
-
-    if (config->use_compression) {
-      Data* uncompressed = data_decompress(file_data);
-      data_destroy(file_data);
-      if (uncompressed == NULL) {
-        file_destroy(file);
-        send_status(fd, STATUS_ERROR);
-        return NULL;
-      }
-      file_data = uncompressed;
-    }
-
-    data_destroy(file->data);
-    file->data = file_data;
-    return file;
+    return receive_file_data(fd, config, check_path);
   }
 
   delta_signature_destroy(sig);
@@ -367,44 +374,9 @@ File* receive_incremental_check(int fd, const Config* config, bool* skipped) {
     }
   }
 
-  File* file = file_create(check_path);
+  File* file = receive_file_data(fd, config, check_path);
   free(check_path);
   free(full_path);
-  if (file == NULL) {
-    send_status(fd, STATUS_ERROR);
-    return NULL;
-  }
-
-  if (config->use_metadata) {
-    int meta_ok = 1;
-    file->metadata = metadata_receive(fd, &meta_ok);
-    if (!meta_ok) {
-      file_destroy(file);
-      send_status(fd, STATUS_ERROR);
-      return NULL;
-    }
-  }
-
-  Data* file_data = receive_data(fd);
-  if (file_data == NULL) {
-    file_destroy(file);
-    send_status(fd, STATUS_ERROR);
-    return NULL;
-  }
-
-  if (config->use_compression) {
-    Data* uncompressed = data_decompress(file_data);
-    data_destroy(file_data);
-    if (uncompressed == NULL) {
-      file_destroy(file);
-      send_status(fd, STATUS_ERROR);
-      return NULL;
-    }
-    file_data = uncompressed;
-  }
-
-  data_destroy(file->data);
-  file->data = file_data;
   return file;
 }
 

src/shared/file.h

@@ -14,10 +14,18 @@ typedef struct {
   long mtime_nsec;
 } FileMetadata;
 
+typedef enum {
+  FILE_TYPE_REGULAR,
+  FILE_TYPE_SYMLINK,
+  FILE_TYPE_DIRECTORY
+} FileType;
+
 typedef struct {
   char* path;
   Data* data;
   FileMetadata* metadata;
+  FileType type;
+  char* link_target;
 } File;
 
 File* file_create(const char* path);

src/shared/log.c

@@ -10,7 +10,7 @@ void set_log_level(LogLevel level) {
   current_log_level = level;
 }
 
-void log_message(LogLevel log_level, char* format, ...) {
+void log_message(LogLevel log_level, const char* format, ...) {
   if (log_level < current_log_level)
     return;
   time_t now = time(NULL);

src/shared/log.h

@@ -3,7 +3,7 @@
 
 typedef enum { LOG_LEVEL_DEBUG, LOG_LEVEL_INFO, LOG_LEVEL_WARNING, LOG_LEVEL_ERROR } LogLevel;
 
-void log_message(LogLevel log_level, char* message, ...);
+void log_message(LogLevel log_level, const char* message, ...);
 void set_log_level(LogLevel level);
 
 #endif

src/shared/multiprocessing.c

@@ -13,6 +13,26 @@
 #include <string.h>
 #include <threads.h>
 
+static const char* filename_from_path(const char* path) {
+  const char* slash = strrchr(path, '/');
+  return slash ? slash + 1 : path;
+}
+
+static bool should_exclude_file(const Config* config, const char* filename) {
+  for (int i = 0; i < config->exclude_count; i++) {
+    if (glob_match(config->exclude_patterns[i], filename))
+      return true;
+  }
+  if (config->include_count > 0) {
+    for (int i = 0; i < config->include_count; i++) {
+      if (glob_match(config->include_patterns[i], filename))
+        return true;
+    }
+    return false;
+  }
+  return false;
+}
+
 PipelineContextSender* pipeline_context_sender_create(Config* config, Queue* queue_scanner,
                                                       Queue* queue_loader) {
   PipelineContextSender* context = malloc(sizeof(PipelineContextSender));
@@ -155,8 +175,10 @@ int write_thread(void* pipeline_context) {
       free(root_directory);
       return thrd_success;
     }
-    if (save_to_disk)
-      file_save_to_disk(root_directory, file);
+    if (save_to_disk) {
+      if (!should_exclude_file(context->config, filename_from_path(file->path)))
+        file_save_to_disk(root_directory, file);
+    }
     file_destroy(file);
   }
 }

src/shared/protocol.c

@@ -34,11 +34,17 @@ static void bw_throttle(size_t bytes_written) {
   struct timespec now;
   clock_gettime(CLOCK_MONOTONIC, &now);
 
-  long long elapsed_ns =
-      (now.tv_sec - bw_last_refill.tv_sec) * 1000000000LL + (now.tv_nsec - bw_last_refill.tv_nsec);
+  /* Use unsigned long long for intermediate computation to avoid overflow.
+   * sec_diff * 1000000000ULL could overflow signed 64-bit for large deltas;
+   * clamp to a safe maximum. */
+  unsigned long long sec_diff = (unsigned long long)(now.tv_sec - bw_last_refill.tv_sec);
+  if (sec_diff > 9223372036ULL)
+    sec_diff = 9223372036ULL;
+  unsigned long long elapsed_ns =
+      sec_diff * 1000000000ULL + (unsigned long long)(now.tv_nsec - bw_last_refill.tv_nsec);
   bw_last_refill = now;
 
-  long long tokens_to_add = (long long)((double)io_bwlimit * elapsed_ns / 1000000000.0);
+  long long tokens_to_add = (long long)((double)io_bwlimit * (double)elapsed_ns / 1000000000.0);
   bw_tokens += tokens_to_add;
   if (bw_tokens > (long long)io_bwlimit)
     bw_tokens = (long long)io_bwlimit;
@@ -74,13 +80,23 @@ bool send_n_data(int file_descriptor, const void* data, size_t data_size) {
     if (io_bwlimit > 0 && chunk > 65536)
       chunk = 65536;
     ssize_t bytes_send;
-    if (io_ssl)
+    if (io_ssl) {
       bytes_send = SSL_write(io_ssl, (const char*)data + total_bytes_send, chunk);
-    else
+      if (bytes_send <= 0) {
+        int err = SSL_get_error(io_ssl, (int)bytes_send);
+        if (err == SSL_ERROR_WANT_WRITE || err == SSL_ERROR_WANT_READ) {
+          /* Non-fatal: retry without counting progress */
+          continue;
+        }
+        log_message(LOG_LEVEL_ERROR, "Could not send data (SSL error: %d)", err);
+        return false;
+      }
+    } else {
       bytes_send = write(fd, (const char*)data + total_bytes_send, chunk);
-    if (bytes_send <= 0) {
-      log_message(LOG_LEVEL_ERROR, "Could not send data");
-      return false;
+      if (bytes_send <= 0) {
+        log_message(LOG_LEVEL_ERROR, "Could not send data");
+        return false;
+      }
     }
     bw_throttle((size_t)bytes_send);
     total_bytes_send += bytes_send;
@@ -95,18 +111,31 @@ bool receive_n_data(int file_descriptor, void* data, size_t data_size) {
   size_t total_bytes_received = 0;
   while (total_bytes_received < data_size) {
     ssize_t bytes_received;
-    if (io_ssl)
+    if (io_ssl) {
       bytes_received =
           SSL_read(io_ssl, (char*)data + total_bytes_received, data_size - total_bytes_received);
-    else
+      if (bytes_received <= 0) {
+        int err = SSL_get_error(io_ssl, (int)bytes_received);
+        if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE) {
+          /* Non-fatal: retry without counting progress */
+          continue;
+        }
+        if (bytes_received == 0)
+          log_message(LOG_LEVEL_ERROR, "Connection closed while receiving data");
+        else
+          log_message(LOG_LEVEL_ERROR, "Could not receive bytes (SSL error: %d)", err);
+        return false;
+      }
+    } else {
       bytes_received =
           read(fd, (char*)data + total_bytes_received, data_size - total_bytes_received);
-    if (bytes_received <= 0) {
-      if (bytes_received == 0)
-        log_message(LOG_LEVEL_ERROR, "Connection closed while receiving data");
-      else
-        log_message(LOG_LEVEL_ERROR, "Could not receive bytes");
-      return false;
+      if (bytes_received <= 0) {
+        if (bytes_received == 0)
+          log_message(LOG_LEVEL_ERROR, "Connection closed while receiving data");
+        else
+          log_message(LOG_LEVEL_ERROR, "Could not receive bytes");
+        return false;
+      }
     }
     total_bytes_received += bytes_received;
   }
@@ -151,6 +180,10 @@ char* receive_str(int file_descriptor) {
   size_t size;
   if (!receive_n_data(file_descriptor, &size, sizeof(size_t)))
     return NULL;
+  if (size > MAX_STRING_SIZE) {
+    log_message(LOG_LEVEL_ERROR, "String size %zu exceeds maximum %d", size, MAX_STRING_SIZE);
+    return NULL;
+  }
   char* data = (char*)malloc(size + 1);
   if (data == NULL)
     return NULL;

src/shared/utils.c

@@ -61,6 +61,24 @@ char* str_dup(const char* string) {
 bool glob_match(const char* pattern, const char* str) {
   while (*pattern) {
     if (*pattern == '*') {
+      if (*(pattern + 1) == '*') {
+        /* ** pattern: matches zero or more characters including '/' */
+        pattern += 2; /* skip both stars */
+        /* If ** is immediately followed by '/', consume it too so that
+         * **/foo behaves intuitively (matches foo at any depth). */
+        if (*pattern == '/')
+          pattern++;
+        /* Try matching the remainder of pattern at every position in str,
+         * including across '/' boundaries and at the very end. */
+        while (1) {
+          if (glob_match(pattern, str))
+            return true;
+          if (*str == '\0')
+            return false;
+          str++;
+        }
+      }
+      /* Single *: matches any characters except '/' */
       pattern++;
       while (*str && *str != '/') {
         if (glob_match(pattern, str))