rsh.c

   1 #include "rsh.h"
   2
   3 #include <string.h>
   4 #include <sys/types.h>
   5 #include <sys/socket.h>
   6
   7 #include "cache.h"
   8
   9 #define COMMAND_SIZE 4096
  10
  11 int setup_connection(int *fd_in, int *fd_out, const char *remote_prog,
  12                      char *url, int rmt_argc, char **rmt_argv)
  13 {
  14         char *host;
  15         char *path;
  16         int sv[2];
  17         char command[COMMAND_SIZE];
  18         char *posn;
  19         int i;
  20
  21         if (!strcmp(url, "-")) {
  22                 *fd_in = 0;
  23                 *fd_out = 1;
  24                 return 0;
  25         }
  26
  27         host = strstr(url, "//");
  28         if (host) {
  29                 host += 2;
  30                 path = strchr(host, '/');
  31         } else {
  32                 host = url;
  33                 path = strchr(host, ':');
  34                 if (path)
  35                         *(path++) = '\0';
  36         }
  37         if (!path) {
  38                 return error("Bad URL: %s", url);
  39         }
  40         /* ssh <host> 'cd <path>; stdio-pull <arg...> <commit-id>' */
  41         snprintf(command, COMMAND_SIZE,
  42                  "%s='%s' %s",
  43                  GIT_DIR_ENVIRONMENT, path, remote_prog);
  44         *path = '\0';
  45         posn = command + strlen(command);
  46         for (i = 0; i < rmt_argc; i++) {
  47                 *(posn++) = ' ';
  48                 strncpy(posn, rmt_argv[i], COMMAND_SIZE - (posn - command));
  49                 posn += strlen(rmt_argv[i]);
  50                 if (posn - command + 4 >= COMMAND_SIZE) {
  51                         return error("Command line too long");
  52                 }
  53         }
  54         strcpy(posn, " -");
  55         if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv)) {
  56                 return error("Couldn't create socket");
  57         }
  58         if (!fork()) {
  59                 const char *ssh = getenv("GIT_SSH") ? : "ssh";
  60                 const char *ssh_basename = strrchr(ssh, '/');
  61                 if (!ssh_basename)
  62                         ssh_basename = ssh;
  63                 else
  64                         ssh_basename++;
  65                 close(sv[1]);
  66                 dup2(sv[0], 0);
  67                 dup2(sv[0], 1);
  68                 execlp(ssh, ssh_basename, host, command, NULL);
  69         }
  70         close(sv[0]);
  71         *fd_in = sv[1];
  72         *fd_out = sv[1];
  73         return 0;
  74 }