send-pack.c

   1 #include "cache.h"
   2 #include "pkt-line.h"
   3
   4 static const char send_pack_usage[] = "git-send-pack [--exec=other] destination [heads]*";
   5 static const char *exec = "git-receive-pack";
   6
   7 static int path_match(const char *path, int nr, char **match)
   8 {
   9         int i;
  10         int pathlen = strlen(path);
  11
  12         for (i = 0; i < nr; i++) {
  13                 char *s = match[i];
  14                 int len = strlen(s);
  15
  16                 if (!len || len > pathlen)
  17                         continue;
  18                 if (memcmp(path + pathlen - len, s, len))
  19                         continue;
  20                 if (pathlen > len && path[pathlen - len - 1] != '/')
  21                         continue;
  22                 *s = 0;
  23                 return 1;
  24         }
  25         return 0;
  26 }
  27
  28 struct ref {
  29         struct ref *next;
  30         unsigned char old_sha1[20];
  31         unsigned char new_sha1[20];
  32         char name[0];
  33 };
  34
  35 static void exec_pack_objects(void)
  36 {
  37         static char *args[] = {
  38                 "git-pack-objects",
  39                 "--stdout",
  40                 NULL
  41         };
  42         execvp("git-pack-objects", args);
  43         die("git-pack-objects exec failed (%s)", strerror(errno));
  44 }
  45
  46 static void exec_rev_list(struct ref *refs)
  47 {
  48         static char *args[1000];
  49         int i = 0;
  50
  51         args[i++] = "git-rev-list";     /* 0 */
  52         args[i++] = "--objects";        /* 1 */
  53         while (refs) {
  54                 char *buf = malloc(100);
  55                 if (i > 900)
  56                         die("git-rev-list environment overflow");
  57                 args[i++] = buf;
  58                 snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
  59                 buf += 50;
  60                 args[i++] = buf;
  61                 snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
  62                 refs = refs->next;
  63         }
  64         args[i] = NULL;
  65         execvp("git-rev-list", args);
  66         die("git-rev-list exec failed (%s)", strerror(errno));
  67 }
  68
  69 static void rev_list(int fd, struct ref *refs)
  70 {
  71         int pipe_fd[2];
  72         pid_t pack_objects_pid;
  73
  74         if (pipe(pipe_fd) < 0)
  75                 die("rev-list setup: pipe failed");
  76         pack_objects_pid = fork();
  77         if (!pack_objects_pid) {
  78                 dup2(pipe_fd[0], 0);
  79                 dup2(fd, 1);
  80                 close(pipe_fd[0]);
  81                 close(pipe_fd[1]);
  82                 close(fd);
  83                 exec_pack_objects();
  84                 die("pack-objects setup failed");
  85         }
  86         if (pack_objects_pid < 0)
  87                 die("pack-objects fork failed");
  88         dup2(pipe_fd[1], 1);
  89         close(pipe_fd[0]);
  90         close(pipe_fd[1]);
  91         close(fd);
  92         exec_rev_list(refs);
  93 }
  94
  95 static int pack_objects(int fd, struct ref *refs)
  96 {
  97         pid_t rev_list_pid;
  98
  99         rev_list_pid = fork();
 100         if (!rev_list_pid) {
 101                 rev_list(fd, refs);
 102                 die("rev-list setup failed");
 103         }
 104         if (rev_list_pid < 0)
 105                 die("rev-list fork failed");
 106         /*
 107          * We don't wait for the rev-list pipeline in the parent:
 108          * we end up waiting for the other end instead
 109          */
 110         return 0;
 111 }
 112
 113 static int read_ref(const char *ref, unsigned char *sha1)
 114 {
 115         int fd, ret;
 116         static char pathname[PATH_MAX];
 117         char buffer[60];
 118         const char *git_dir = gitenv(GIT_DIR_ENVIRONMENT) ? : DEFAULT_GIT_DIR_ENVIRONMENT;
 119
 120         snprintf(pathname, sizeof(pathname), "%s/%s", git_dir, ref);
 121         fd = open(pathname, O_RDONLY);
 122         if (fd < 0)
 123                 return -1;
 124         ret = -1;
 125         if (read(fd, buffer, sizeof(buffer)) >= 40)
 126                 ret = get_sha1_hex(buffer, sha1);
 127         close(fd);
 128         return ret;
 129 }
 130
 131 static int send_pack(int in, int out, int nr_match, char **match)
 132 {
 133         struct ref *ref_list = NULL, **last_ref = &ref_list;
 134         struct ref *ref;
 135
 136         for (;;) {
 137                 unsigned char old_sha1[20];
 138                 unsigned char new_sha1[20];
 139                 static char buffer[1000];
 140                 char *name;
 141                 int len;
 142
 143                 len = packet_read_line(in, buffer, sizeof(buffer));
 144                 if (!len)
 145                         break;
 146                 if (buffer[len-1] == '\n')
 147                         buffer[--len] = 0;
 148
 149                 if (len < 42 || get_sha1_hex(buffer, old_sha1) || buffer[40] != ' ')
 150                         die("protocol error: expected sha/ref, got '%s'", buffer);
 151                 name = buffer + 41;
 152                 if (nr_match && !path_match(name, nr_match, match))
 153                         continue;
 154                 if (read_ref(name, new_sha1) < 0)
 155                         return error("no such local reference '%s'", name);
 156                 if (!has_sha1_file(old_sha1))
 157                         return error("remote '%s' points to object I don't have", name);
 158                 if (!memcmp(old_sha1, new_sha1, 20)) {
 159                         fprintf(stderr, "'%s' unchanged\n", name);
 160                         continue;
 161                 }
 162                 ref = xmalloc(sizeof(*ref) + len - 40);
 163                 memcpy(ref->old_sha1, old_sha1, 20);
 164                 memcpy(ref->new_sha1, new_sha1, 20);
 165                 memcpy(ref->name, buffer + 41, len - 40);
 166                 ref->next = NULL;
 167                 *last_ref = ref;
 168                 last_ref = &ref->next;
 169         }
 170
 171         for (ref = ref_list; ref; ref = ref->next) {
 172                 char old_hex[60], *new_hex;
 173                 strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 174                 new_hex = sha1_to_hex(ref->new_sha1);
 175                 packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
 176                 fprintf(stderr, "'%s': updating from %s to %s\n", ref->name, old_hex, new_hex);
 177         }
 178
 179         packet_flush(out);
 180         if (ref_list)
 181                 pack_objects(out, ref_list);
 182         close(out);
 183         return 0;
 184 }
 185
 186 int main(int argc, char **argv)
 187 {
 188         int i, nr_heads = 0;
 189         char *dest = NULL;
 190         char **heads = NULL;
 191         int fd[2], ret;
 192         pid_t pid;
 193
 194         argv++;
 195         for (i = 1; i < argc; i++) {
 196                 char *arg = *argv++;
 197
 198                 if (*arg == '-') {
 199                         if (!strncmp(arg, "--exec=", 7)) {
 200                                 exec = arg + 7;
 201                                 continue;
 202                         }
 203                         usage(send_pack_usage);
 204                 }
 205                 dest = arg;
 206                 heads = argv;
 207                 nr_heads = argc - i -1;
 208                 break;
 209         }
 210         if (!dest)
 211                 usage(send_pack_usage);
 212         pid = git_connect(fd, dest, exec);
 213         if (pid < 0)
 214                 return 1;
 215         ret = send_pack(fd[0], fd[1], nr_heads, heads);
 216         close(fd[0]);
 217         close(fd[1]);
 218         finish_connect(pid);
 219         return ret;
 220 }