fetch-pack.con commit Document "git cherry-pick" and "git revert" (de2b82c)
   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include <sys/wait.h>
   5
   6static int quiet;
   7static int verbose;
   8static const char fetch_pack_usage[] =
   9"git-fetch-pack [-q] [-v] [--exec=upload-pack] [host:]directory <refs>...";
  10static const char *exec = "git-upload-pack";
  11
  12static int find_common(int fd[2], unsigned char *result_sha1,
  13                       struct ref *refs)
  14{
  15        static char line[1000];
  16        int count = 0, flushes = 0, retval;
  17        FILE *revs;
  18
  19        revs = popen("git-rev-list $(git-rev-parse --all)", "r");
  20        if (!revs)
  21                die("unable to run 'git-rev-list'");
  22
  23        while (refs) {
  24                unsigned char *remote = refs->old_sha1;
  25                if (verbose)
  26                        fprintf(stderr,
  27                                "want %s (%s)\n", sha1_to_hex(remote),
  28                                refs->name);
  29                packet_write(fd[1], "want %s\n", sha1_to_hex(remote));
  30                refs = refs->next;
  31        }
  32        packet_flush(fd[1]);
  33        flushes = 1;
  34        retval = -1;
  35        while (fgets(line, sizeof(line), revs) != NULL) {
  36                unsigned char sha1[20];
  37                if (get_sha1_hex(line, sha1))
  38                        die("git-fetch-pack: expected object name, got crud");
  39                packet_write(fd[1], "have %s\n", sha1_to_hex(sha1));
  40                if (verbose)
  41                        fprintf(stderr, "have %s\n", sha1_to_hex(sha1));
  42                if (!(31 & ++count)) {
  43                        packet_flush(fd[1]);
  44                        flushes++;
  45
  46                        /*
  47                         * We keep one window "ahead" of the other side, and
  48                         * will wait for an ACK only on the next one
  49                         */
  50                        if (count == 32)
  51                                continue;
  52                        if (get_ack(fd[0], result_sha1)) {
  53                                flushes = 0;
  54                                retval = 0;
  55                                if (verbose)
  56                                        fprintf(stderr, "got ack\n");
  57                                break;
  58                        }
  59                        flushes--;
  60                }
  61        }
  62        pclose(revs);
  63        packet_write(fd[1], "done\n");
  64        if (verbose)
  65                fprintf(stderr, "done\n");
  66        while (flushes) {
  67                flushes--;
  68                if (get_ack(fd[0], result_sha1)) {
  69                        if (verbose)
  70                                fprintf(stderr, "got ack\n");
  71                        return 0;
  72                }
  73        }
  74        return retval;
  75}
  76
  77static int fetch_pack(int fd[2], int nr_match, char **match)
  78{
  79        struct ref *ref;
  80        unsigned char sha1[20];
  81        int status;
  82        pid_t pid;
  83
  84        get_remote_heads(fd[0], &ref, nr_match, match);
  85        if (!ref) {
  86                packet_flush(fd[1]);
  87                die("no matching remote head");
  88        }
  89        if (find_common(fd, sha1, ref) < 0)
  90                fprintf(stderr, "warning: no common commits\n");
  91        pid = fork();
  92        if (pid < 0)
  93                die("git-fetch-pack: unable to fork off git-unpack-objects");
  94        if (!pid) {
  95                dup2(fd[0], 0);
  96                close(fd[0]);
  97                close(fd[1]);
  98                execlp("git-unpack-objects", "git-unpack-objects",
  99                       quiet ? "-q" : NULL, NULL);
 100                die("git-unpack-objects exec failed");
 101        }
 102        close(fd[0]);
 103        close(fd[1]);
 104        while (waitpid(pid, &status, 0) < 0) {
 105                if (errno != EINTR)
 106                        die("waiting for git-unpack-objects: %s", strerror(errno));
 107        }
 108        if (WIFEXITED(status)) {
 109                int code = WEXITSTATUS(status);
 110                if (code)
 111                        die("git-unpack-objects died with error code %d", code);
 112                while (ref) {
 113                        printf("%s %s\n",
 114                               sha1_to_hex(ref->old_sha1), ref->name);
 115                        ref = ref->next;
 116                }
 117                return 0;
 118        }
 119        if (WIFSIGNALED(status)) {
 120                int sig = WTERMSIG(status);
 121                die("git-unpack-objects died of signal %d", sig);
 122        }
 123        die("Sherlock Holmes! git-unpack-objects died of unnatural causes %d!", status);
 124}
 125
 126int main(int argc, char **argv)
 127{
 128        int i, ret, nr_heads;
 129        char *dest = NULL, **heads;
 130        int fd[2];
 131        pid_t pid;
 132
 133        nr_heads = 0;
 134        heads = NULL;
 135        for (i = 1; i < argc; i++) {
 136                char *arg = argv[i];
 137
 138                if (*arg == '-') {
 139                        if (!strncmp("--exec=", arg, 7)) {
 140                                exec = arg + 7;
 141                                continue;
 142                        }
 143                        if (!strcmp("-q", arg)) {
 144                                quiet = 1;
 145                                continue;
 146                        }
 147                        if (!strcmp("-v", arg)) {
 148                                verbose = 1;
 149                                continue;
 150                        }
 151                        usage(fetch_pack_usage);
 152                }
 153                dest = arg;
 154                heads = argv + i + 1;
 155                nr_heads = argc - i - 1;
 156                break;
 157        }
 158        if (!dest)
 159                usage(fetch_pack_usage);
 160        pid = git_connect(fd, dest, exec);
 161        if (pid < 0)
 162                return 1;
 163        ret = fetch_pack(fd, nr_heads, heads);
 164        close(fd[0]);
 165        close(fd[1]);
 166        finish_connect(pid);
 167        return ret;
 168}