send.c

#include <arpa/inet.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int main(int argc, char *argv[]) {
  if (argc < 2) {
    perror("No file was inputed");
    return EXIT_FAILURE;
  }
  const int PORT = 8080;
  const int BUFFER_SIZE = 4096;

  struct sockaddr_in server_addr;
  char buffer[BUFFER_SIZE];

  int sock = socket(AF_INET, SOCK_STREAM, 0);
  if (sock < 0) {
    perror("Socket failed");
    exit(EXIT_FAILURE);
  }

  server_addr.sin_family = AF_INET;
  server_addr.sin_port = htons(PORT);
  inet_pton(AF_INET, "127.0.0.1", &server_addr.sin_addr);

  if (connect(sock, (struct sockaddr *)&server_addr, sizeof(server_addr))) {
    perror("Connection failed");
    exit(EXIT_FAILURE);
  }

  printf("Connected to server.\n");
  FILE *files[argc - 1];
  for (int i = 0; i < argc - 1; i++) {
    files[i] = fopen(argv[i + 1], "rb");
    if (files[i] == NULL) {
      for (int j = 0; j < i; j++) {
        fclose(files[j]);
      }
      close(sock);
      perror("Error when opening file");
      return EXIT_FAILURE;
    }
  }
  uint32_t argc_buffer = htonl(argc - 1);
  printf("%zu file(s) will be sent.\n", (unsigned long)argc - 1);
  write(sock, &argc_buffer, sizeof(argc_buffer));
  for (int i = 1; i < argc; i++) {
    memset(buffer, 0, BUFFER_SIZE);
    strcpy(buffer, argv[i]);
    write(sock, buffer, BUFFER_SIZE);
  }
  int pos = 0;
  while (pos < argc - 1) {

    memset(buffer, 0, BUFFER_SIZE);
    int bytes_read = fread(buffer, sizeof(char), BUFFER_SIZE, files[pos]);
    if (bytes_read < BUFFER_SIZE) {
      if (feof(files[pos])) {
        printf("Sending file %d: %s\n", pos + 1, argv[pos + 1]);
        fclose(files[pos]);
        pos++;
      } else {
        perror("File reading error");
        for (int i = 0; i < argc - 1; i++) {
          fclose(files[i]);
        }
        close(sock);
        return EXIT_FAILURE;
      }
    }
    write(sock, buffer, bytes_read);
  }

  close(sock);
  return 0;
}