send-pack.con commit GIT 1.0.0 (c2f3bf0)
   1#include "cache.h"
   2#include "commit.h"
   3#include "tag.h"
   4#include "refs.h"
   5#include "pkt-line.h"
   6
   7static const char send_pack_usage[] =
   8"git-send-pack [--all] [--exec=git-receive-pack] <remote> [<head>...]\n"
   9"  --all and explicit <head> specification are mutually exclusive.";
  10static const char *exec = "git-receive-pack";
  11static int verbose = 0;
  12static int send_all = 0;
  13static int force_update = 0;
  14
  15static int is_zero_sha1(const unsigned char *sha1)
  16{
  17        int i;
  18
  19        for (i = 0; i < 20; i++) {
  20                if (*sha1++)
  21                        return 0;
  22        }
  23        return 1;
  24}
  25
  26static void exec_pack_objects(void)
  27{
  28        static char *args[] = {
  29                "git-pack-objects",
  30                "--stdout",
  31                NULL
  32        };
  33        execvp("git-pack-objects", args);
  34        die("git-pack-objects exec failed (%s)", strerror(errno));
  35}
  36
  37static void exec_rev_list(struct ref *refs)
  38{
  39        static char *args[1000];
  40        int i = 0;
  41
  42        args[i++] = "git-rev-list";     /* 0 */
  43        args[i++] = "--objects";        /* 1 */
  44        while (refs) {
  45                char *buf = malloc(100);
  46                if (i > 900)
  47                        die("git-rev-list environment overflow");
  48                if (!is_zero_sha1(refs->old_sha1) &&
  49                    has_sha1_file(refs->old_sha1)) {
  50                        args[i++] = buf;
  51                        snprintf(buf, 50, "^%s", sha1_to_hex(refs->old_sha1));
  52                        buf += 50;
  53                }
  54                if (!is_zero_sha1(refs->new_sha1)) {
  55                        args[i++] = buf;
  56                        snprintf(buf, 50, "%s", sha1_to_hex(refs->new_sha1));
  57                }
  58                refs = refs->next;
  59        }
  60        args[i] = NULL;
  61        execvp("git-rev-list", args);
  62        die("git-rev-list exec failed (%s)", strerror(errno));
  63}
  64
  65static void rev_list(int fd, struct ref *refs)
  66{
  67        int pipe_fd[2];
  68        pid_t pack_objects_pid;
  69
  70        if (pipe(pipe_fd) < 0)
  71                die("rev-list setup: pipe failed");
  72        pack_objects_pid = fork();
  73        if (!pack_objects_pid) {
  74                dup2(pipe_fd[0], 0);
  75                dup2(fd, 1);
  76                close(pipe_fd[0]);
  77                close(pipe_fd[1]);
  78                close(fd);
  79                exec_pack_objects();
  80                die("pack-objects setup failed");
  81        }
  82        if (pack_objects_pid < 0)
  83                die("pack-objects fork failed");
  84        dup2(pipe_fd[1], 1);
  85        close(pipe_fd[0]);
  86        close(pipe_fd[1]);
  87        close(fd);
  88        exec_rev_list(refs);
  89}
  90
  91static int pack_objects(int fd, struct ref *refs)
  92{
  93        pid_t rev_list_pid;
  94
  95        rev_list_pid = fork();
  96        if (!rev_list_pid) {
  97                rev_list(fd, refs);
  98                die("rev-list setup failed");
  99        }
 100        if (rev_list_pid < 0)
 101                die("rev-list fork failed");
 102        /*
 103         * We don't wait for the rev-list pipeline in the parent:
 104         * we end up waiting for the other end instead
 105         */
 106        return 0;
 107}
 108
 109static void unmark_and_free(struct commit_list *list, unsigned int mark)
 110{
 111        while (list) {
 112                struct commit_list *temp = list;
 113                temp->item->object.flags &= ~mark;
 114                list = temp->next;
 115                free(temp);
 116        }
 117}
 118
 119static int ref_newer(const unsigned char *new_sha1,
 120                     const unsigned char *old_sha1)
 121{
 122        struct object *o;
 123        struct commit *old, *new;
 124        struct commit_list *list, *used;
 125        int found = 0;
 126
 127        /* Both new and old must be commit-ish and new is descendant of
 128         * old.  Otherwise we require --force.
 129         */
 130        o = deref_tag(parse_object(old_sha1), NULL, 0);
 131        if (!o || o->type != commit_type)
 132                return 0;
 133        old = (struct commit *) o;
 134
 135        o = deref_tag(parse_object(new_sha1), NULL, 0);
 136        if (!o || o->type != commit_type)
 137                return 0;
 138        new = (struct commit *) o;
 139
 140        if (parse_commit(new) < 0)
 141                return 0;
 142
 143        used = list = NULL;
 144        commit_list_insert(new, &list);
 145        while (list) {
 146                new = pop_most_recent_commit(&list, 1);
 147                commit_list_insert(new, &used);
 148                if (new == old) {
 149                        found = 1;
 150                        break;
 151                }
 152        }
 153        unmark_and_free(list, 1);
 154        unmark_and_free(used, 1);
 155        return found;
 156}
 157
 158static struct ref *local_refs, **local_tail;
 159static struct ref *remote_refs, **remote_tail;
 160
 161static int one_local_ref(const char *refname, const unsigned char *sha1)
 162{
 163        struct ref *ref;
 164        int len = strlen(refname) + 1;
 165        ref = xcalloc(1, sizeof(*ref) + len);
 166        memcpy(ref->new_sha1, sha1, 20);
 167        memcpy(ref->name, refname, len);
 168        *local_tail = ref;
 169        local_tail = &ref->next;
 170        return 0;
 171}
 172
 173static void get_local_heads(void)
 174{
 175        local_tail = &local_refs;
 176        for_each_ref(one_local_ref);
 177}
 178
 179static int send_pack(int in, int out, int nr_refspec, char **refspec)
 180{
 181        struct ref *ref;
 182        int new_refs;
 183        int ret = 0;
 184
 185        /* No funny business with the matcher */
 186        remote_tail = get_remote_heads(in, &remote_refs, 0, NULL, 1);
 187        get_local_heads();
 188
 189        /* match them up */
 190        if (!remote_tail)
 191                remote_tail = &remote_refs;
 192        if (match_refs(local_refs, remote_refs, &remote_tail,
 193                       nr_refspec, refspec, send_all))
 194                return -1;
 195
 196        if (!remote_refs) {
 197                fprintf(stderr, "No refs in common and none specified; doing nothing.\n");
 198                return 0;
 199        }
 200
 201        /*
 202         * Finally, tell the other end!
 203         */
 204        new_refs = 0;
 205        for (ref = remote_refs; ref; ref = ref->next) {
 206                char old_hex[60], *new_hex;
 207                if (!ref->peer_ref)
 208                        continue;
 209                if (!memcmp(ref->old_sha1, ref->peer_ref->new_sha1, 20)) {
 210                        if (verbose)
 211                                fprintf(stderr, "'%s': up-to-date\n", ref->name);
 212                        continue;
 213                }
 214
 215                /* This part determines what can overwrite what.
 216                 * The rules are:
 217                 *
 218                 * (0) you can always use --force or +A:B notation to
 219                 *     selectively force individual ref pairs.
 220                 *
 221                 * (1) if the old thing does not exist, it is OK.
 222                 *
 223                 * (2) if you do not have the old thing, you are not allowed
 224                 *     to overwrite it; you would not know what you are losing
 225                 *     otherwise.
 226                 *
 227                 * (3) if both new and old are commit-ish, and new is a
 228                 *     descendant of old, it is OK.
 229                 */
 230
 231                if (!force_update &&
 232                    !is_zero_sha1(ref->old_sha1) &&
 233                    !ref->force) {
 234                        if (!has_sha1_file(ref->old_sha1)) {
 235                                error("remote '%s' object %s does not "
 236                                      "exist on local",
 237                                      ref->name, sha1_to_hex(ref->old_sha1));
 238                                ret = -2;
 239                                continue;
 240                        }
 241
 242                        /* We assume that local is fsck-clean.  Otherwise
 243                         * you _could_ have an old tag which points at
 244                         * something you do not have, which may or may not
 245                         * be a commit.
 246                         */
 247                        if (!ref_newer(ref->peer_ref->new_sha1,
 248                                       ref->old_sha1)) {
 249                                error("remote ref '%s' is not a strict "
 250                                      "subset of local ref '%s'.", ref->name,
 251                                      ref->peer_ref->name);
 252                                ret = -2;
 253                                continue;
 254                        }
 255                }
 256                memcpy(ref->new_sha1, ref->peer_ref->new_sha1, 20);
 257                if (is_zero_sha1(ref->new_sha1)) {
 258                        error("cannot happen anymore");
 259                        ret = -3;
 260                        continue;
 261                }
 262                new_refs++;
 263                strcpy(old_hex, sha1_to_hex(ref->old_sha1));
 264                new_hex = sha1_to_hex(ref->new_sha1);
 265                packet_write(out, "%s %s %s", old_hex, new_hex, ref->name);
 266                fprintf(stderr, "updating '%s'", ref->name);
 267                if (strcmp(ref->name, ref->peer_ref->name))
 268                        fprintf(stderr, " using '%s'", ref->peer_ref->name);
 269                fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
 270        }
 271
 272        packet_flush(out);
 273        if (new_refs)
 274                pack_objects(out, remote_refs);
 275        else
 276                fprintf(stderr, "Everything up-to-date\n");
 277        close(out);
 278        return ret;
 279}
 280
 281
 282int main(int argc, char **argv)
 283{
 284        int i, nr_heads = 0;
 285        char *dest = NULL;
 286        char **heads = NULL;
 287        int fd[2], ret;
 288        pid_t pid;
 289
 290        setup_git_directory();
 291        argv++;
 292        for (i = 1; i < argc; i++, argv++) {
 293                char *arg = *argv;
 294
 295                if (*arg == '-') {
 296                        if (!strncmp(arg, "--exec=", 7)) {
 297                                exec = arg + 7;
 298                                continue;
 299                        }
 300                        if (!strcmp(arg, "--all")) {
 301                                send_all = 1;
 302                                continue;
 303                        }
 304                        if (!strcmp(arg, "--force")) {
 305                                force_update = 1;
 306                                continue;
 307                        }
 308                        if (!strcmp(arg, "--verbose")) {
 309                                verbose = 1;
 310                                continue;
 311                        }
 312                        usage(send_pack_usage);
 313                }
 314                if (!dest) {
 315                        dest = arg;
 316                        continue;
 317                }
 318                heads = argv;
 319                nr_heads = argc - i;
 320                break;
 321        }
 322        if (!dest)
 323                usage(send_pack_usage);
 324        if (heads && send_all)
 325                usage(send_pack_usage);
 326        pid = git_connect(fd, dest, exec);
 327        if (pid < 0)
 328                return 1;
 329        ret = send_pack(fd[0], fd[1], nr_heads, heads);
 330        close(fd[0]);
 331        close(fd[1]);
 332        finish_connect(pid);
 333        return ret;
 334}