Merge branch 'main' into metadata-transfer, resolve conflicts

Conflicts resolved:
- config_create signature: added both use_metadata and use_sendfile params
- config_send/config_receive: wire protocol includes both use_metadata and use_sendfile
- client.c: config_create call updated, arg parsing includes both -M/--preserve and -f/--sendfile
- test_config.c: all three config_create calls updated
- file_send_sendfile: use file->data->size instead of removed struct stat

src/shared/config.c

@@ -7,8 +7,8 @@
 Config *config_create(char *version, char *send_directory,
                       char *receive_directory, bool save_to_disk,
                       bool use_multithreading, bool use_chunk_serialization,
-                      bool use_compression, bool use_metadata,
-                      int compression_level, int num_connections) {
+                       bool use_compression, bool use_metadata,
+                       int compression_level, int num_connections, bool use_sendfile) {
 
   Config *config = malloc(sizeof(Config));
   config->version = version;
@@ -21,6 +21,7 @@ Config *config_create(char *version, char *send_directory,
   config->use_metadata = use_metadata;
   config->compression_level = compression_level;
   config->num_connections = num_connections;
+  config->use_sendfile = use_sendfile;
   return config;
 }
 
@@ -42,6 +43,7 @@ void config_send(int file_descriptor, Config *config) {
   send_int(file_descriptor, config->use_metadata);
   send_int(file_descriptor, config->compression_level);
   send_int(file_descriptor, config->num_connections);
+  send_int(file_descriptor, config->use_sendfile);
   if (receive_status(file_descriptor) != STATUS_OK) {
     perror("Error transmitting config!");
     exit(EXIT_FAILURE);
@@ -60,6 +62,7 @@ Config *config_receive(int file_descriptor) {
   config->use_metadata = receive_int(file_descriptor);
   config->compression_level = receive_int(file_descriptor);
   config->num_connections = receive_int(file_descriptor);
+  config->use_sendfile = receive_int(file_descriptor);
   send_status(file_descriptor, STATUS_OK);
   return config;
 }

src/shared/config.h

@@ -11,6 +11,7 @@ typedef struct Config {
   bool use_multithreading;
   bool use_chunk_serialization;
   bool use_compression;
+  bool use_sendfile;
   bool use_single_send_per_file;
   bool use_metadata;
   int compression_level;
@@ -20,8 +21,8 @@ typedef struct Config {
 Config *config_create(char *version, char *send_directory,
                       char *receive_directory, bool save_to_disk,
                       bool use_multithreading, bool use_chunk_serialization,
-                      bool use_compression, bool use_metadata,
-                      int compression_level, int num_connections);
+                       bool use_compression, bool use_metadata,
+                       int compression_level, int num_connections, bool use_sendfile);
 void config_delete(Config *config);
 void config_send(int file_descriptor, Config *config);
 Config *config_receive(int file_descriptor);

src/shared/file.c

@@ -1,9 +1,12 @@
 #include <dirent.h>
+#include <fcntl.h>
 #include <libgen.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/sendfile.h>
+#include <unistd.h>
 #include <zstd.h>
 
 #include "data.h"
@@ -122,6 +125,31 @@ void file_send_single_calls(File *file, int file_descriptor) {
   send_data(file_descriptor, file->data->data, file->data->size);
 }
 
+void file_send_sendfile(File *file, int file_descriptor) {
+  send_str(file_descriptor, file->path);
+
+  int fd = open(file->path, O_RDONLY);
+  if (fd == -1) {
+    perror("Could not open file for sendfile");
+    exit(EXIT_FAILURE);
+  }
+
+  unsigned long long file_size = file->data->size;
+  send_n_data(file_descriptor, &file_size, sizeof(unsigned long long));
+
+  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);
+      exit(EXIT_FAILURE);
+    }
+  }
+
+  close(fd);
+}
+
 size_t file_content_to_buffer(File *file) {
   FILE *file_pointer = fopen(file->path, "rb");
   if (file_pointer == NULL) {

src/shared/file.h

@@ -23,6 +23,7 @@ void file_destroy(void *item);
 void file_load_data(File *file);
 void file_print(void *item);
 void file_send_single_calls(File *file, int file_descriptor);
+void file_send_sendfile(File *file, int file_descriptor);
 size_t file_content_to_buffer(File *file);
 FileMetadata *file_metadata_create(struct stat *stats);
 void file_metadata_destroy(void *metadata);