upload-pack.con commit make index-pack able to complete thin packs. (636171c)
   1#include <signal.h>
   2#include <sys/wait.h>
   3#include <sys/poll.h>
   4#include "cache.h"
   5#include "refs.h"
   6#include "pkt-line.h"
   7#include "sideband.h"
   8#include "tag.h"
   9#include "object.h"
  10#include "commit.h"
  11#include "exec_cmd.h"
  12
  13static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
  14
  15#define THEY_HAVE (1U << 0)
  16#define OUR_REF (1U << 1)
  17#define WANTED (1U << 2)
  18static int multi_ack, nr_our_refs;
  19static int use_thin_pack, use_ofs_delta;
  20static struct object_array have_obj;
  21static struct object_array want_obj;
  22static unsigned int timeout;
  23/* 0 for no sideband,
  24 * otherwise maximum packet size (up to 65520 bytes).
  25 */
  26static int use_sideband;
  27
  28static void reset_timeout(void)
  29{
  30        alarm(timeout);
  31}
  32
  33static int strip(char *line, int len)
  34{
  35        if (len && line[len-1] == '\n')
  36                line[--len] = 0;
  37        return len;
  38}
  39
  40static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
  41{
  42        if (use_sideband)
  43                return send_sideband(1, fd, data, sz, use_sideband);
  44        if (fd == 3)
  45                /* emergency quit */
  46                fd = 2;
  47        if (fd == 2) {
  48                xwrite(fd, data, sz);
  49                return sz;
  50        }
  51        return safe_write(fd, data, sz);
  52}
  53
  54static void create_pack_file(void)
  55{
  56        /* Pipes between rev-list to pack-objects, pack-objects to us
  57         * and pack-objects error stream for progress bar.
  58         */
  59        int lp_pipe[2], pu_pipe[2], pe_pipe[2];
  60        pid_t pid_rev_list, pid_pack_objects;
  61        int create_full_pack = (nr_our_refs == want_obj.nr && !have_obj.nr);
  62        char data[8193], progress[128];
  63        char abort_msg[] = "aborting due to possible repository "
  64                "corruption on the remote side.";
  65        int buffered = -1;
  66
  67        if (pipe(lp_pipe) < 0)
  68                die("git-upload-pack: unable to create pipe");
  69        pid_rev_list = fork();
  70        if (pid_rev_list < 0)
  71                die("git-upload-pack: unable to fork git-rev-list");
  72
  73        if (!pid_rev_list) {
  74                int i;
  75                int args;
  76                const char **argv;
  77                const char **p;
  78                char *buf;
  79
  80                if (create_full_pack) {
  81                        args = 10;
  82                        use_thin_pack = 0; /* no point doing it */
  83                }
  84                else
  85                        args = have_obj.nr + want_obj.nr + 5;
  86                p = xmalloc(args * sizeof(char *));
  87                argv = (const char **) p;
  88                buf = xmalloc(args * 45);
  89
  90                dup2(lp_pipe[1], 1);
  91                close(0);
  92                close(lp_pipe[0]);
  93                close(lp_pipe[1]);
  94                *p++ = "rev-list";
  95                *p++ = use_thin_pack ? "--objects-edge" : "--objects";
  96                if (create_full_pack)
  97                        *p++ = "--all";
  98                else {
  99                        for (i = 0; i < want_obj.nr; i++) {
 100                                struct object *o = want_obj.objects[i].item;
 101                                *p++ = buf;
 102                                memcpy(buf, sha1_to_hex(o->sha1), 41);
 103                                buf += 41;
 104                        }
 105                }
 106                if (!create_full_pack)
 107                        for (i = 0; i < have_obj.nr; i++) {
 108                                struct object *o = have_obj.objects[i].item;
 109                                *p++ = buf;
 110                                *buf++ = '^';
 111                                memcpy(buf, sha1_to_hex(o->sha1), 41);
 112                                buf += 41;
 113                        }
 114                *p++ = NULL;
 115                execv_git_cmd(argv);
 116                die("git-upload-pack: unable to exec git-rev-list");
 117        }
 118
 119        if (pipe(pu_pipe) < 0)
 120                die("git-upload-pack: unable to create pipe");
 121        if (pipe(pe_pipe) < 0)
 122                die("git-upload-pack: unable to create pipe");
 123        pid_pack_objects = fork();
 124        if (pid_pack_objects < 0) {
 125                /* daemon sets things up to ignore TERM */
 126                kill(pid_rev_list, SIGKILL);
 127                die("git-upload-pack: unable to fork git-pack-objects");
 128        }
 129        if (!pid_pack_objects) {
 130                dup2(lp_pipe[0], 0);
 131                dup2(pu_pipe[1], 1);
 132                dup2(pe_pipe[1], 2);
 133
 134                close(lp_pipe[0]);
 135                close(lp_pipe[1]);
 136                close(pu_pipe[0]);
 137                close(pu_pipe[1]);
 138                close(pe_pipe[0]);
 139                close(pe_pipe[1]);
 140                execl_git_cmd("pack-objects", "--stdout", "--progress",
 141                              use_ofs_delta ? "--delta-base-offset" : NULL,
 142                              NULL);
 143                kill(pid_rev_list, SIGKILL);
 144                die("git-upload-pack: unable to exec git-pack-objects");
 145        }
 146
 147        close(lp_pipe[0]);
 148        close(lp_pipe[1]);
 149
 150        /* We read from pe_pipe[0] to capture stderr output for
 151         * progress bar, and pu_pipe[0] to capture the pack data.
 152         */
 153        close(pe_pipe[1]);
 154        close(pu_pipe[1]);
 155
 156        while (1) {
 157                const char *who;
 158                struct pollfd pfd[2];
 159                pid_t pid;
 160                int status;
 161                ssize_t sz;
 162                int pe, pu, pollsize;
 163
 164                reset_timeout();
 165
 166                pollsize = 0;
 167                pe = pu = -1;
 168
 169                if (0 <= pu_pipe[0]) {
 170                        pfd[pollsize].fd = pu_pipe[0];
 171                        pfd[pollsize].events = POLLIN;
 172                        pu = pollsize;
 173                        pollsize++;
 174                }
 175                if (0 <= pe_pipe[0]) {
 176                        pfd[pollsize].fd = pe_pipe[0];
 177                        pfd[pollsize].events = POLLIN;
 178                        pe = pollsize;
 179                        pollsize++;
 180                }
 181
 182                if (pollsize) {
 183                        if (poll(pfd, pollsize, -1) < 0) {
 184                                if (errno != EINTR) {
 185                                        error("poll failed, resuming: %s",
 186                                              strerror(errno));
 187                                        sleep(1);
 188                                }
 189                                continue;
 190                        }
 191                        if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 192                                /* Data ready; we keep the last byte
 193                                 * to ourselves in case we detect
 194                                 * broken rev-list, so that we can
 195                                 * leave the stream corrupted.  This
 196                                 * is unfortunate -- unpack-objects
 197                                 * would happily accept a valid pack
 198                                 * data with trailing garbage, so
 199                                 * appending garbage after we pass all
 200                                 * the pack data is not good enough to
 201                                 * signal breakage to downstream.
 202                                 */
 203                                char *cp = data;
 204                                ssize_t outsz = 0;
 205                                if (0 <= buffered) {
 206                                        *cp++ = buffered;
 207                                        outsz++;
 208                                }
 209                                sz = read(pu_pipe[0], cp,
 210                                          sizeof(data) - outsz);
 211                                if (0 < sz)
 212                                                ;
 213                                else if (sz == 0) {
 214                                        close(pu_pipe[0]);
 215                                        pu_pipe[0] = -1;
 216                                }
 217                                else
 218                                        goto fail;
 219                                sz += outsz;
 220                                if (1 < sz) {
 221                                        buffered = data[sz-1] & 0xFF;
 222                                        sz--;
 223                                }
 224                                else
 225                                        buffered = -1;
 226                                sz = send_client_data(1, data, sz);
 227                                if (sz < 0)
 228                                        goto fail;
 229                        }
 230                        if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 231                                /* Status ready; we ship that in the side-band
 232                                 * or dump to the standard error.
 233                                 */
 234                                sz = read(pe_pipe[0], progress,
 235                                          sizeof(progress));
 236                                if (0 < sz)
 237                                        send_client_data(2, progress, sz);
 238                                else if (sz == 0) {
 239                                        close(pe_pipe[0]);
 240                                        pe_pipe[0] = -1;
 241                                }
 242                                else
 243                                        goto fail;
 244                        }
 245                }
 246
 247                /* See if the children are still there */
 248                if (pid_rev_list || pid_pack_objects) {
 249                        pid = waitpid(-1, &status, WNOHANG);
 250                        if (!pid)
 251                                continue;
 252                        who = ((pid == pid_rev_list) ? "git-rev-list" :
 253                               (pid == pid_pack_objects) ? "git-pack-objects" :
 254                               NULL);
 255                        if (!who) {
 256                                if (pid < 0) {
 257                                        error("git-upload-pack: %s",
 258                                              strerror(errno));
 259                                        goto fail;
 260                                }
 261                                error("git-upload-pack: we weren't "
 262                                      "waiting for %d", pid);
 263                                continue;
 264                        }
 265                        if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) {
 266                                error("git-upload-pack: %s died with error.",
 267                                      who);
 268                                goto fail;
 269                        }
 270                        if (pid == pid_rev_list)
 271                                pid_rev_list = 0;
 272                        if (pid == pid_pack_objects)
 273                                pid_pack_objects = 0;
 274                        if (pid_rev_list || pid_pack_objects)
 275                                continue;
 276                }
 277
 278                /* both died happily */
 279                if (pollsize)
 280                        continue;
 281
 282                /* flush the data */
 283                if (0 <= buffered) {
 284                        data[0] = buffered;
 285                        sz = send_client_data(1, data, 1);
 286                        if (sz < 0)
 287                                goto fail;
 288                        fprintf(stderr, "flushed.\n");
 289                }
 290                if (use_sideband)
 291                        packet_flush(1);
 292                return;
 293        }
 294 fail:
 295        if (pid_pack_objects)
 296                kill(pid_pack_objects, SIGKILL);
 297        if (pid_rev_list)
 298                kill(pid_rev_list, SIGKILL);
 299        send_client_data(3, abort_msg, sizeof(abort_msg));
 300        die("git-upload-pack: %s", abort_msg);
 301}
 302
 303static int got_sha1(char *hex, unsigned char *sha1)
 304{
 305        struct object *o;
 306
 307        if (get_sha1_hex(hex, sha1))
 308                die("git-upload-pack: expected SHA1 object, got '%s'", hex);
 309        if (!has_sha1_file(sha1))
 310                return 0;
 311
 312        o = lookup_object(sha1);
 313        if (!(o && o->parsed))
 314                o = parse_object(sha1);
 315        if (!o)
 316                die("oops (%s)", sha1_to_hex(sha1));
 317        if (o->type == OBJ_COMMIT) {
 318                struct commit_list *parents;
 319                if (o->flags & THEY_HAVE)
 320                        return 0;
 321                o->flags |= THEY_HAVE;
 322                for (parents = ((struct commit*)o)->parents;
 323                     parents;
 324                     parents = parents->next)
 325                        parents->item->object.flags |= THEY_HAVE;
 326        }
 327        add_object_array(o, NULL, &have_obj);
 328        return 1;
 329}
 330
 331static int get_common_commits(void)
 332{
 333        static char line[1000];
 334        unsigned char sha1[20];
 335        char hex[41], last_hex[41];
 336        int len;
 337
 338        track_object_refs = 0;
 339        save_commit_buffer = 0;
 340
 341        for(;;) {
 342                len = packet_read_line(0, line, sizeof(line));
 343                reset_timeout();
 344
 345                if (!len) {
 346                        if (have_obj.nr == 0 || multi_ack)
 347                                packet_write(1, "NAK\n");
 348                        continue;
 349                }
 350                len = strip(line, len);
 351                if (!strncmp(line, "have ", 5)) {
 352                        if (got_sha1(line+5, sha1)) {
 353                                memcpy(hex, sha1_to_hex(sha1), 41);
 354                                if (multi_ack) {
 355                                        const char *msg = "ACK %s continue\n";
 356                                        packet_write(1, msg, hex);
 357                                        memcpy(last_hex, hex, 41);
 358                                }
 359                                else if (have_obj.nr == 1)
 360                                        packet_write(1, "ACK %s\n", hex);
 361                        }
 362                        continue;
 363                }
 364                if (!strcmp(line, "done")) {
 365                        if (have_obj.nr > 0) {
 366                                if (multi_ack)
 367                                        packet_write(1, "ACK %s\n", last_hex);
 368                                return 0;
 369                        }
 370                        packet_write(1, "NAK\n");
 371                        return -1;
 372                }
 373                die("git-upload-pack: expected SHA1 list, got '%s'", line);
 374        }
 375}
 376
 377static void receive_needs(void)
 378{
 379        static char line[1000];
 380        int len;
 381
 382        for (;;) {
 383                struct object *o;
 384                unsigned char sha1_buf[20];
 385                len = packet_read_line(0, line, sizeof(line));
 386                reset_timeout();
 387                if (!len)
 388                        return;
 389
 390                if (strncmp("want ", line, 5) ||
 391                    get_sha1_hex(line+5, sha1_buf))
 392                        die("git-upload-pack: protocol error, "
 393                            "expected to get sha, not '%s'", line);
 394                if (strstr(line+45, "multi_ack"))
 395                        multi_ack = 1;
 396                if (strstr(line+45, "thin-pack"))
 397                        use_thin_pack = 1;
 398                if (strstr(line+45, "ofs-delta"))
 399                        use_ofs_delta = 1;
 400                if (strstr(line+45, "side-band-64k"))
 401                        use_sideband = LARGE_PACKET_MAX;
 402                else if (strstr(line+45, "side-band"))
 403                        use_sideband = DEFAULT_PACKET_MAX;
 404
 405                /* We have sent all our refs already, and the other end
 406                 * should have chosen out of them; otherwise they are
 407                 * asking for nonsense.
 408                 *
 409                 * Hmph.  We may later want to allow "want" line that
 410                 * asks for something like "master~10" (symbolic)...
 411                 * would it make sense?  I don't know.
 412                 */
 413                o = lookup_object(sha1_buf);
 414                if (!o || !(o->flags & OUR_REF))
 415                        die("git-upload-pack: not our ref %s", line+5);
 416                if (!(o->flags & WANTED)) {
 417                        o->flags |= WANTED;
 418                        add_object_array(o, NULL, &want_obj);
 419                }
 420        }
 421}
 422
 423static int send_ref(const char *refname, const unsigned char *sha1)
 424{
 425        static const char *capabilities = "multi_ack thin-pack side-band side-band-64k ofs-delta";
 426        struct object *o = parse_object(sha1);
 427
 428        if (!o)
 429                die("git-upload-pack: cannot find object %s:", sha1_to_hex(sha1));
 430
 431        if (capabilities)
 432                packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
 433                        0, capabilities);
 434        else
 435                packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
 436        capabilities = NULL;
 437        if (!(o->flags & OUR_REF)) {
 438                o->flags |= OUR_REF;
 439                nr_our_refs++;
 440        }
 441        if (o->type == OBJ_TAG) {
 442                o = deref_tag(o, refname, 0);
 443                packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
 444        }
 445        return 0;
 446}
 447
 448static void upload_pack(void)
 449{
 450        reset_timeout();
 451        head_ref(send_ref);
 452        for_each_ref(send_ref);
 453        packet_flush(1);
 454        receive_needs();
 455        if (want_obj.nr) {
 456                get_common_commits();
 457                create_pack_file();
 458        }
 459}
 460
 461int main(int argc, char **argv)
 462{
 463        char *dir;
 464        int i;
 465        int strict = 0;
 466
 467        for (i = 1; i < argc; i++) {
 468                char *arg = argv[i];
 469
 470                if (arg[0] != '-')
 471                        break;
 472                if (!strcmp(arg, "--strict")) {
 473                        strict = 1;
 474                        continue;
 475                }
 476                if (!strncmp(arg, "--timeout=", 10)) {
 477                        timeout = atoi(arg+10);
 478                        continue;
 479                }
 480                if (!strcmp(arg, "--")) {
 481                        i++;
 482                        break;
 483                }
 484        }
 485        
 486        if (i != argc-1)
 487                usage(upload_pack_usage);
 488        dir = argv[i];
 489
 490        if (!enter_repo(dir, strict))
 491                die("'%s': unable to chdir or not a git archive", dir);
 492
 493        upload_pack();
 494        return 0;
 495}