src/client/client_cli.c

@@ -205,6 +205,16 @@ int main(int argc, char *argv[]) {
     return 1;
   }
 
+  if (config->use_incremental && config->use_chunk_serialization) {
+    fprintf(stderr, "Error: --incremental is not supported with -s (chunk serialization)\n");
+    return 1;
+  }
+
+  if (config->use_incremental && !config->use_metadata) {
+    log_message(LOG_LEVEL_INFO, "Enabling metadata preservation for --incremental");
+    config->use_metadata = true;
+  }
+
   if (config->use_multithreading)
     return send_files_multithreaded(config);
   return send_files(config);

src/client/client_send.c

@@ -41,13 +41,16 @@ int send_chunk(Client *client, Chunk *chunk, Config *config) {
         if (!send_n_data(client->file_descriptor, &mtime, sizeof(mtime))) return -1;
         Status s;
         if (!receive_status(client->file_descriptor, &s)) return -1;
+        if (s == STATUS_ERROR) { log_message(LOG_LEVEL_ERROR, "Server reported error for file"); return -1; }
         if (s == STATUS_OK) continue;
-        if (s != STATUS_NEXT) return -1;
+        if (s != STATUS_NEXT) { log_message(LOG_LEVEL_ERROR, "Unexpected server status"); return -1; }
+        if (!file_send_sendfile_no_path(chunk->items[i], client->file_descriptor, config->use_metadata))
+          return -1;
       } else {
         if (!send_status(client->file_descriptor, STATUS_NEXT)) return -1;
+        if (!file_send_sendfile(chunk->items[i], client->file_descriptor, config->use_metadata))
+          return -1;
       }
-      if (!file_send_sendfile(chunk->items[i], client->file_descriptor, config->use_metadata))
-        return -1;
     }
   } else {
     for (int i = 0; i < chunk->element_count; i++) {
@@ -60,8 +63,9 @@ int send_chunk(Client *client, Chunk *chunk, Config *config) {
         if (!send_n_data(client->file_descriptor, &mtime, sizeof(mtime))) return -1;
         Status s;
         if (!receive_status(client->file_descriptor, &s)) return -1;
+        if (s == STATUS_ERROR) { log_message(LOG_LEVEL_ERROR, "Server reported error for file"); return -1; }
         if (s == STATUS_OK) continue;
-        if (s != STATUS_NEXT) return -1;
+        if (s != STATUS_NEXT) { log_message(LOG_LEVEL_ERROR, "Unexpected server status"); return -1; }
         if (!file_send_single_calls_no_path(chunk->items[i], client->file_descriptor,
                                        config->use_metadata,
                                        config->use_compression ? config->compression_level : 0))

src/shared/config.h

@@ -35,7 +35,7 @@ typedef struct Config {
   bool use_incremental;
 } Config;
 
-#define PROTOCOL_VERSION "1.0.0"
+#define PROTOCOL_VERSION "1.1.0"
 #define DEFAULT_CHUNK_SIZE (10 * 1024 * 1024)
 
 Config *config_create(char *version, char *send_directory,

src/shared/file.c

@@ -97,37 +97,81 @@ bool file_load_data(File *file) {
 }
 
 bool file_send_single_calls_no_path(File *file, int file_descriptor, bool use_metadata, int compression_level) {
+  Data *data_to_send = file->data;
+  Data *compressed_data = NULL;
   if (compression_level > 0) {
-    Data *compressed_data = data_compress(file->data, compression_level);
+    compressed_data = data_compress(file->data, compression_level);
     if (compressed_data == NULL) {
       log_message(LOG_LEVEL_ERROR, "Failed to compress file data");
       return false;
     }
-    data_destroy(file->data);
+    data_to_send = compressed_data;
-    file->data = compressed_data;
   }
+  if (use_metadata && !metadata_send(file_descriptor, file->metadata)) {
+    data_destroy(compressed_data);
+    return false;
+  }
+  if (!send_data(file_descriptor, data_to_send)) {
+    data_destroy(compressed_data);
+    return false;
+  }
+  data_destroy(compressed_data);
+  return true;
+}
+
+bool file_send_sendfile_no_path(File *file, int file_descriptor, bool use_metadata) {
   if (use_metadata && !metadata_send(file_descriptor, file->metadata)) return false;
-  if (!send_data(file_descriptor, file->data)) return false;
+
+  int fd = open(file->path, O_RDONLY);
+  if (fd == -1) {
+    perror("Could not open file for sendfile");
+    return false;
+  }
+
+  unsigned long long file_size = file->data->size;
+  if (!send_n_data(file_descriptor, &file_size, sizeof(unsigned long long))) {
+    close(fd);
+    return false;
+  }
+
+  off_t offset = 0;
+  while (offset < file_size) {
+    ssize_t sent = sendfile(file_descriptor, fd, &offset, file_size - offset);
+    if (sent == -1) {
+      perror("sendfile failed");
+      close(fd);
+      return false;
+    }
+  }
+
+  close(fd);
   return true;
 }
 
 bool file_send_single_calls(File *file, int file_descriptor, bool use_metadata, int compression_level) {
+  Data *data_to_send = file->data;
+  Data *compressed_data = NULL;
   if (compression_level > 0) {
-    Data *compressed_data = data_compress(file->data, compression_level);
+    compressed_data = data_compress(file->data, compression_level);
     if (compressed_data == NULL) {
       log_message(LOG_LEVEL_ERROR, "Failed to compress file data");
       return false;
     }
-    data_destroy(file->data);
+    data_to_send = compressed_data;
-    if (compressed_data == NULL) {
-      log_message(LOG_LEVEL_ERROR, "Compression failed in file_send_single_calls");
-      exit(EXIT_FAILURE);
-    }
-    file->data = compressed_data;
   }
-  if (!send_str(file_descriptor, file->path)) return false;
+  if (!send_str(file_descriptor, file->path)) {
-  if (use_metadata && !metadata_send(file_descriptor, file->metadata)) return false;
+    data_destroy(compressed_data);
-  if (!send_data(file_descriptor, file->data)) return false;
+    return false;
+  }
+  if (use_metadata && !metadata_send(file_descriptor, file->metadata)) {
+    data_destroy(compressed_data);
+    return false;
+  }
+  if (!send_data(file_descriptor, data_to_send)) {
+    data_destroy(compressed_data);
+    return false;
+  }
+  data_destroy(compressed_data);
   return true;
 }
 

src/shared/file.h

@@ -27,6 +27,7 @@ File *file_receive(Config *config, int file_descriptor);
 bool file_send_single_calls(File *file, int file_descriptor, bool use_metadata, int compression_level);
 bool file_send_single_calls_no_path(File *file, int file_descriptor, bool use_metadata, int compression_level);
 bool file_send_sendfile(File *file, int file_descriptor, bool use_metadata);
+bool file_send_sendfile_no_path(File *file, int file_descriptor, bool use_metadata);
 size_t file_content_to_buffer(File *file);
 FileMetadata *file_metadata_create(struct stat *stats);
 void file_metadata_destroy(void *metadata);