Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include <sys/wait.h>
   5
   6static int quiet;
   7static const char fetch_pack_usage[] = "git-fetch-pack [-q] [--exec=upload-pack] [host:]directory [heads]* < mycommitlist";
   8static const char *exec = "git-upload-pack";
   9
  10static int find_common(int fd[2], unsigned char *result_sha1, unsigned char *remote)
  11{
  12        static char line[1000];
  13        int count = 0, flushes = 0, retval;
  14        FILE *revs;
  15
  16        revs = popen("git-rev-list $(git-rev-parse --all)", "r");
  17        if (!revs)
  18                die("unable to run 'git-rev-list'");
  19        packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
  20        packet_flush(fd[1]);
  21        flushes = 1;
  22        retval = -1;
  23        while (fgets(line, sizeof(line), revs) != NULL) {
  24                unsigned char sha1[20];
  25                if (get_sha1_hex(line, sha1))
  26                        die("git-fetch-pack: expected object name, got crud");
  27                packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
  28                if (!(31 & ++count)) {
  29                        packet_flush(fd[1]);
  30                        flushes++;
  31
  32                        /*
  33                         * We keep one window "ahead" of the other side, and
  34                         * will wait for an ACK only on the next one
  35                         */
  36                        if (count == 32)
  37                                continue;
  38                        if (get_ack(fd[0], result_sha1)) {
  39                                flushes = 0;
  40                                retval = 0;
  41                                break;
  42                        }
  43                        flushes--;
  44                }
  45        }
  46        pclose(revs);
  47        packet_write(fd[1], "done\n");
  48        while (flushes) {
  49                flushes--;
  50                if (get_ack(fd[0], result_sha1))
  51                        return 0;
  52        }
  53        return retval;
  54}
  55
  56/*
  57 * Eventually we'll want to be able to fetch multiple heads.
  58 *
  59 * Right now we'll just require a single match.
  60 */
  61static int fetch_pack(int fd[2], int nr_match, char **match)
  62{
  63        struct ref *ref;
  64        unsigned char sha1[20];
  65        int status;
  66        pid_t pid;
  67
  68        get_remote_heads(fd[0], &ref, nr_match, match);
  69        if (!ref) {
  70                packet_flush(fd[1]);
  71                die("no matching remote head");
  72        }
  73        if (ref->next) {
  74                packet_flush(fd[1]);
  75                die("multiple remote heads");
  76        }
  77        if (find_common(fd, sha1, ref->old_sha1) < 0)
  78                die("git-fetch-pack: no common commits");
  79        pid = fork();
  80        if (pid < 0)
  81                die("git-fetch-pack: unable to fork off git-unpack-objects");
  82        if (!pid) {
  83                dup2(fd[0], 0);
  84                close(fd[0]);
  85                close(fd[1]);
  86                execlp("git-unpack-objects", "git-unpack-objects",
  87                       quiet ? "-q" : NULL, NULL);
  88                die("git-unpack-objects exec failed");
  89        }
  90        close(fd[0]);
  91        close(fd[1]);
  92        while (waitpid(pid, &status, 0) < 0) {
  93                if (errno != EINTR)
  94                        die("waiting for git-unpack-objects: %s", strerror(errno));
  95        }
  96        if (WIFEXITED(status)) {
  97                int code = WEXITSTATUS(status);
  98                if (code)
  99                        die("git-unpack-objects died with error code %d", code);
 100                puts(sha1_to_hex(ref->old_sha1));
 101                return 0;
 102        }
 103        if (WIFSIGNALED(status)) {
 104                int sig = WTERMSIG(status);
 105                die("git-unpack-objects died of signal %d", sig);
 106        }
 107        die("Sherlock Holmes! git-unpack-objects died of unnatural causes %d!", status);
 108}
 109
 110int main(int argc, char **argv)
 111{
 112        int i, ret, nr_heads;
 113        char *dest = NULL, **heads;
 114        int fd[2];
 115        pid_t pid;
 116
 117        nr_heads = 0;
 118        heads = NULL;
 119        for (i = 1; i < argc; i++) {
 120                char *arg = argv[i];
 121
 122                if (*arg == '-') {
 123                        if (!strncmp("--exec=", arg, 7)) {
 124                                exec = arg + 7;
 125                                continue;
 126                        }
 127                        usage(fetch_pack_usage);
 128                }
 129                dest = arg;
 130                heads = argv + i + 1;
 131                nr_heads = argc - i - 1;
 132                break;
 133        }
 134        if (!dest)
 135                usage(fetch_pack_usage);
 136        pid = git_connect(fd, dest, exec);
 137        if (pid < 0)
 138                return 1;
 139        ret = fetch_pack(fd, nr_heads, heads);
 140        close(fd[0]);
 141        close(fd[1]);
 142        finish_connect(pid);
 143        return ret;
 144}