rsh.c

   1 #include "rsh.h"
   2
   3 #include <string.h>
   4 #include <sys/socket.h>
   5
   6 #include "cache.h"
   7
   8 #define COMMAND_SIZE 4096
   9
  10 int setup_connection(int *fd_in, int *fd_out, char *remote_prog,
  11                      char *url, int rmt_argc, char **rmt_argv)
  12 {
  13         char *host;
  14         char *path;
  15         int sv[2];
  16         char command[COMMAND_SIZE];
  17         char *posn;
  18         int i;
  19
  20         if (!strcmp(url, "-")) {
  21                 *fd_in = 0;
  22                 *fd_out = 1;
  23                 return 0;
  24         }
  25
  26         host = strstr(url, "//");
  27         if (!host) {
  28                 return error("Bad URL: %s", url);
  29         }
  30         host += 2;
  31         path = strchr(host, '/');
  32         if (!path) {
  33                 return error("Bad URL: %s", url);
  34         }
  35         *(path++) = '\0';
  36         /* ssh <host> 'cd /<path>; stdio-pull <arg...> <commit-id>' */
  37         snprintf(command, COMMAND_SIZE,
  38                  "cd /%s; SHA1_FILE_DIRECTORY=objects %s",
  39                  path, remote_prog);
  40         posn = command + strlen(command);
  41         for (i = 0; i < rmt_argc; i++) {
  42                 *(posn++) = ' ';
  43                 strncpy(posn, rmt_argv[i], COMMAND_SIZE - (posn - command));
  44                 posn += strlen(rmt_argv[i]);
  45                 if (posn - command + 4 >= COMMAND_SIZE) {
  46                         return error("Command line too long");
  47                 }
  48         }
  49         strcpy(posn, " -");
  50         if (socketpair(AF_LOCAL, SOCK_STREAM, 0, sv)) {
  51                 return error("Couldn't create socket");
  52         }
  53         if (!fork()) {
  54                 close(sv[1]);
  55                 dup2(sv[0], 0);
  56                 dup2(sv[0], 1);
  57                 execlp("ssh", "ssh", host, command, NULL);
  58         }
  59         close(sv[0]);
  60         *fd_in = sv[1];
  61         *fd_out = sv[1];
  62         return 0;
  63 }