fetch-clone.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "pkt-line.h"
   4 #include "sideband.h"
   5 #include <sys/wait.h>
   6
   7 static pid_t setup_sideband(int sideband, const char *me, int fd[2], int xd[2])
   8 {
   9         pid_t side_pid;
  10
  11         if (!sideband) {
  12                 fd[0] = xd[0];
  13                 fd[1] = xd[1];
  14                 return 0;
  15         }
  16         /* xd[] is talking with upload-pack; subprocess reads from
  17          * xd[0], spits out band#2 to stderr, and feeds us band#1
  18          * through our fd[0].
  19          */
  20         if (pipe(fd) < 0)
  21                 die("%s: unable to set up pipe", me);
  22         side_pid = fork();
  23         if (side_pid < 0)
  24                 die("%s: unable to fork off sideband demultiplexer", me);
  25         if (!side_pid) {
  26                 /* subprocess */
  27                 close(fd[0]);
  28                 if (xd[0] != xd[1])
  29                         close(xd[1]);
  30                 if (recv_sideband(me, xd[0], fd[1], 2))
  31                         exit(1);
  32                 exit(0);
  33         }
  34         close(xd[0]);
  35         close(fd[1]);
  36         fd[1] = xd[1];
  37         return side_pid;
  38 }
  39
  40 static int get_pack(int xd[2], const char *me, int sideband, const char **argv)
  41 {
  42         int status;
  43         pid_t pid, side_pid;
  44         int fd[2];
  45
  46         side_pid = setup_sideband(sideband, me, fd, xd);
  47         pid = fork();
  48         if (pid < 0)
  49                 die("%s: unable to fork off %s", me, argv[0]);
  50         if (!pid) {
  51                 dup2(fd[0], 0);
  52                 close(fd[0]);
  53                 close(fd[1]);
  54                 execv_git_cmd(argv);
  55                 die("%s exec failed", argv[0]);
  56         }
  57         close(fd[0]);
  58         close(fd[1]);
  59         while (waitpid(pid, &status, 0) < 0) {
  60                 if (errno != EINTR)
  61                         die("waiting for %s: %s", argv[0], strerror(errno));
  62         }
  63         if (WIFEXITED(status)) {
  64                 int code = WEXITSTATUS(status);
  65                 if (code)
  66                         die("%s died with error code %d", argv[0], code);
  67                 return 0;
  68         }
  69         if (WIFSIGNALED(status)) {
  70                 int sig = WTERMSIG(status);
  71                 die("%s died of signal %d", argv[0], sig);
  72         }
  73         die("%s died of unnatural causes %d", argv[0], status);
  74 }
  75
  76 int receive_unpack_pack(int xd[2], const char *me, int quiet, int sideband)
  77 {
  78         const char *argv[3] = { "unpack-objects", quiet ? "-q" : NULL, NULL };
  79         return get_pack(xd, me, sideband, argv);
  80 }
  81
  82 int receive_keep_pack(int xd[2], const char *me, int quiet, int sideband)
  83 {
  84         const char *argv[5] = { "index-pack", "--stdin", "--fix-thin",
  85                                 quiet ? NULL : "-v", NULL };
  86         return get_pack(xd, me, sideband, argv);
  87 }