upload-pack.con commit git-svn: add the commit-diff command (27e9fb8)
   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include "tag.h"
   5#include "object.h"
   6#include "commit.h"
   7#include "exec_cmd.h"
   8#include <signal.h>
   9#include <sys/poll.h>
  10#include <sys/wait.h>
  11
  12static const char upload_pack_usage[] = "git-upload-pack [--strict] [--timeout=nn] <dir>";
  13
  14#define THEY_HAVE (1U << 0)
  15#define OUR_REF (1U << 1)
  16#define WANTED (1U << 2)
  17#define MAX_HAS 256
  18#define MAX_NEEDS 256
  19static int nr_has = 0, nr_needs = 0, multi_ack = 0, nr_our_refs = 0;
  20static int use_thin_pack = 0;
  21static unsigned char has_sha1[MAX_HAS][20];
  22static unsigned char needs_sha1[MAX_NEEDS][20];
  23static unsigned int timeout = 0;
  24static int use_sideband = 0;
  25
  26static void reset_timeout(void)
  27{
  28        alarm(timeout);
  29}
  30
  31static int strip(char *line, int len)
  32{
  33        if (len && line[len-1] == '\n')
  34                line[--len] = 0;
  35        return len;
  36}
  37
  38#define PACKET_MAX 1000
  39static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
  40{
  41        ssize_t ssz;
  42        const char *p;
  43
  44        if (!data) {
  45                if (!use_sideband)
  46                        return 0;
  47                packet_flush(1);
  48        }
  49
  50        if (!use_sideband) {
  51                if (fd == 3)
  52                        /* emergency quit */
  53                        fd = 2;
  54                return safe_write(fd, data, sz);
  55        }
  56        p = data;
  57        ssz = sz;
  58        while (sz) {
  59                unsigned n;
  60                char hdr[5];
  61
  62                n = sz;
  63                if (PACKET_MAX - 5 < n)
  64                        n = PACKET_MAX - 5;
  65                sprintf(hdr, "%04x", n + 5);
  66                hdr[4] = fd;
  67                safe_write(1, hdr, 5);
  68                safe_write(1, p, n);
  69                p += n;
  70                sz -= n;
  71        }
  72        return ssz;
  73}
  74
  75static void create_pack_file(void)
  76{
  77        /* Pipes between rev-list to pack-objects, pack-objects to us
  78         * and pack-objects error stream for progress bar.
  79         */
  80        int lp_pipe[2], pu_pipe[2], pe_pipe[2];
  81        pid_t pid_rev_list, pid_pack_objects;
  82        int create_full_pack = (nr_our_refs == nr_needs && !nr_has);
  83        char data[8193], progress[128];
  84        char abort_msg[] = "aborting due to possible repository "
  85                "corruption on the remote side.";
  86        int buffered = -1;
  87
  88        if (pipe(lp_pipe) < 0)
  89                die("git-upload-pack: unable to create pipe");
  90        pid_rev_list = fork();
  91        if (pid_rev_list < 0)
  92                die("git-upload-pack: unable to fork git-rev-list");
  93
  94        if (!pid_rev_list) {
  95                int i;
  96                int args;
  97                const char **argv;
  98                char *buf;
  99                char **p;
 100
 101                if (create_full_pack) {
 102                        args = 10;
 103                        use_thin_pack = 0; /* no point doing it */
 104                }
 105                else
 106                        args = nr_has + nr_needs + 5;
 107                p = xmalloc(args * sizeof(char *));
 108                argv = (const char **) p;
 109                buf = xmalloc(args * 45);
 110
 111                dup2(lp_pipe[1], 1);
 112                close(0);
 113                close(lp_pipe[0]);
 114                close(lp_pipe[1]);
 115                *p++ = "rev-list";
 116                *p++ = use_thin_pack ? "--objects-edge" : "--objects";
 117                if (create_full_pack || MAX_NEEDS <= nr_needs)
 118                        *p++ = "--all";
 119                else {
 120                        for (i = 0; i < nr_needs; i++) {
 121                                *p++ = buf;
 122                                memcpy(buf, sha1_to_hex(needs_sha1[i]), 41);
 123                                buf += 41;
 124                        }
 125                }
 126                if (!create_full_pack)
 127                        for (i = 0; i < nr_has; i++) {
 128                                *p++ = buf;
 129                                *buf++ = '^';
 130                                memcpy(buf, sha1_to_hex(has_sha1[i]), 41);
 131                                buf += 41;
 132                        }
 133                *p++ = NULL;
 134                execv_git_cmd(argv);
 135                die("git-upload-pack: unable to exec git-rev-list");
 136        }
 137
 138        if (pipe(pu_pipe) < 0)
 139                die("git-upload-pack: unable to create pipe");
 140        if (pipe(pe_pipe) < 0)
 141                die("git-upload-pack: unable to create pipe");
 142        pid_pack_objects = fork();
 143        if (pid_pack_objects < 0) {
 144                /* daemon sets things up to ignore TERM */
 145                kill(pid_rev_list, SIGKILL);
 146                die("git-upload-pack: unable to fork git-pack-objects");
 147        }
 148        if (!pid_pack_objects) {
 149                dup2(lp_pipe[0], 0);
 150                dup2(pu_pipe[1], 1);
 151                dup2(pe_pipe[1], 2);
 152
 153                close(lp_pipe[0]);
 154                close(lp_pipe[1]);
 155                close(pu_pipe[0]);
 156                close(pu_pipe[1]);
 157                close(pe_pipe[0]);
 158                close(pe_pipe[1]);
 159                execl_git_cmd("pack-objects", "--stdout", "--progress", NULL);
 160                kill(pid_rev_list, SIGKILL);
 161                die("git-upload-pack: unable to exec git-pack-objects");
 162        }
 163
 164        close(lp_pipe[0]);
 165        close(lp_pipe[1]);
 166
 167        /* We read from pe_pipe[0] to capture stderr output for
 168         * progress bar, and pu_pipe[0] to capture the pack data.
 169         */
 170        close(pe_pipe[1]);
 171        close(pu_pipe[1]);
 172
 173        while (1) {
 174                const char *who;
 175                struct pollfd pfd[2];
 176                pid_t pid;
 177                int status;
 178                ssize_t sz;
 179                int pe, pu, pollsize;
 180
 181                pollsize = 0;
 182                pe = pu = -1;
 183
 184                if (0 <= pu_pipe[0]) {
 185                        pfd[pollsize].fd = pu_pipe[0];
 186                        pfd[pollsize].events = POLLIN;
 187                        pu = pollsize;
 188                        pollsize++;
 189                }
 190                if (0 <= pe_pipe[0]) {
 191                        pfd[pollsize].fd = pe_pipe[0];
 192                        pfd[pollsize].events = POLLIN;
 193                        pe = pollsize;
 194                        pollsize++;
 195                }
 196
 197                if (pollsize) {
 198                        if (poll(pfd, pollsize, -1) < 0) {
 199                                if (errno != EINTR) {
 200                                        error("poll failed, resuming: %s",
 201                                              strerror(errno));
 202                                        sleep(1);
 203                                }
 204                                continue;
 205                        }
 206                        if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
 207                                /* Data ready; we keep the last byte
 208                                 * to ourselves in case we detect
 209                                 * broken rev-list, so that we can
 210                                 * leave the stream corrupted.  This
 211                                 * is unfortunate -- unpack-objects
 212                                 * would happily accept a valid pack
 213                                 * data with trailing garbage, so
 214                                 * appending garbage after we pass all
 215                                 * the pack data is not good enough to
 216                                 * signal breakage to downstream.
 217                                 */
 218                                char *cp = data;
 219                                ssize_t outsz = 0;
 220                                if (0 <= buffered) {
 221                                        *cp++ = buffered;
 222                                        outsz++;
 223                                }
 224                                sz = read(pu_pipe[0], cp,
 225                                          sizeof(data) - outsz);
 226                                if (0 < sz)
 227                                                ;
 228                                else if (sz == 0) {
 229                                        close(pu_pipe[0]);
 230                                        pu_pipe[0] = -1;
 231                                }
 232                                else
 233                                        goto fail;
 234                                sz += outsz;
 235                                if (1 < sz) {
 236                                        buffered = data[sz-1] & 0xFF;
 237                                        sz--;
 238                                }
 239                                else
 240                                        buffered = -1;
 241                                sz = send_client_data(1, data, sz);
 242                                if (sz < 0)
 243                                        goto fail;
 244                        }
 245                        if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
 246                                /* Status ready; we ship that in the side-band
 247                                 * or dump to the standard error.
 248                                 */
 249                                sz = read(pe_pipe[0], progress,
 250                                          sizeof(progress));
 251                                if (0 < sz)
 252                                        send_client_data(2, progress, sz);
 253                                else if (sz == 0) {
 254                                        close(pe_pipe[0]);
 255                                        pe_pipe[0] = -1;
 256                                }
 257                                else
 258                                        goto fail;
 259                        }
 260                }
 261
 262                /* See if the children are still there */
 263                if (pid_rev_list || pid_pack_objects) {
 264                        pid = waitpid(-1, &status, WNOHANG);
 265                        if (!pid)
 266                                continue;
 267                        who = ((pid == pid_rev_list) ? "git-rev-list" :
 268                               (pid == pid_pack_objects) ? "git-pack-objects" :
 269                               NULL);
 270                        if (!who) {
 271                                if (pid < 0) {
 272                                        error("git-upload-pack: %s",
 273                                              strerror(errno));
 274                                        goto fail;
 275                                }
 276                                error("git-upload-pack: we weren't "
 277                                      "waiting for %d", pid);
 278                                continue;
 279                        }
 280                        if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) {
 281                                error("git-upload-pack: %s died with error.",
 282                                      who);
 283                                goto fail;
 284                        }
 285                        if (pid == pid_rev_list)
 286                                pid_rev_list = 0;
 287                        if (pid == pid_pack_objects)
 288                                pid_pack_objects = 0;
 289                        if (pid_rev_list || pid_pack_objects)
 290                                continue;
 291                }
 292
 293                /* both died happily */
 294                if (pollsize)
 295                        continue;
 296
 297                /* flush the data */
 298                if (0 <= buffered) {
 299                        data[0] = buffered;
 300                        sz = send_client_data(1, data, 1);
 301                        if (sz < 0)
 302                                goto fail;
 303                        fprintf(stderr, "flushed.\n");
 304                }
 305                send_client_data(1, NULL, 0);
 306                return;
 307        }
 308 fail:
 309        if (pid_pack_objects)
 310                kill(pid_pack_objects, SIGKILL);
 311        if (pid_rev_list)
 312                kill(pid_rev_list, SIGKILL);
 313        send_client_data(3, abort_msg, sizeof(abort_msg));
 314        die("git-upload-pack: %s", abort_msg);
 315}
 316
 317static int got_sha1(char *hex, unsigned char *sha1)
 318{
 319        if (get_sha1_hex(hex, sha1))
 320                die("git-upload-pack: expected SHA1 object, got '%s'", hex);
 321        if (!has_sha1_file(sha1))
 322                return 0;
 323        if (nr_has < MAX_HAS) {
 324                struct object *o = lookup_object(sha1);
 325                if (!(o && o->parsed))
 326                        o = parse_object(sha1);
 327                if (!o)
 328                        die("oops (%s)", sha1_to_hex(sha1));
 329                if (o->type == TYPE_COMMIT) {
 330                        struct commit_list *parents;
 331                        if (o->flags & THEY_HAVE)
 332                                return 0;
 333                        o->flags |= THEY_HAVE;
 334                        for (parents = ((struct commit*)o)->parents;
 335                             parents;
 336                             parents = parents->next)
 337                                parents->item->object.flags |= THEY_HAVE;
 338                }
 339                memcpy(has_sha1[nr_has++], sha1, 20);
 340        }
 341        return 1;
 342}
 343
 344static int get_common_commits(void)
 345{
 346        static char line[1000];
 347        unsigned char sha1[20], last_sha1[20];
 348        int len;
 349
 350        track_object_refs = 0;
 351        save_commit_buffer = 0;
 352
 353        for(;;) {
 354                len = packet_read_line(0, line, sizeof(line));
 355                reset_timeout();
 356
 357                if (!len) {
 358                        if (nr_has == 0 || multi_ack)
 359                                packet_write(1, "NAK\n");
 360                        continue;
 361                }
 362                len = strip(line, len);
 363                if (!strncmp(line, "have ", 5)) {
 364                        if (got_sha1(line+5, sha1) &&
 365                                        (multi_ack || nr_has == 1)) {
 366                                if (nr_has >= MAX_HAS)
 367                                        multi_ack = 0;
 368                                packet_write(1, "ACK %s%s\n",
 369                                        sha1_to_hex(sha1),
 370                                        multi_ack ?  " continue" : "");
 371                                if (multi_ack)
 372                                        memcpy(last_sha1, sha1, 20);
 373                        }
 374                        continue;
 375                }
 376                if (!strcmp(line, "done")) {
 377                        if (nr_has > 0) {
 378                                if (multi_ack)
 379                                        packet_write(1, "ACK %s\n",
 380                                                        sha1_to_hex(last_sha1));
 381                                return 0;
 382                        }
 383                        packet_write(1, "NAK\n");
 384                        return -1;
 385                }
 386                die("git-upload-pack: expected SHA1 list, got '%s'", line);
 387        }
 388}
 389
 390static int receive_needs(void)
 391{
 392        static char line[1000];
 393        int len, needs;
 394
 395        needs = 0;
 396        for (;;) {
 397                struct object *o;
 398                unsigned char dummy[20], *sha1_buf;
 399                len = packet_read_line(0, line, sizeof(line));
 400                reset_timeout();
 401                if (!len)
 402                        return needs;
 403
 404                sha1_buf = dummy;
 405                if (needs == MAX_NEEDS) {
 406                        fprintf(stderr,
 407                                "warning: supporting only a max of %d requests. "
 408                                "sending everything instead.\n",
 409                                MAX_NEEDS);
 410                }
 411                else if (needs < MAX_NEEDS)
 412                        sha1_buf = needs_sha1[needs];
 413
 414                if (strncmp("want ", line, 5) || get_sha1_hex(line+5, sha1_buf))
 415                        die("git-upload-pack: protocol error, "
 416                            "expected to get sha, not '%s'", line);
 417                if (strstr(line+45, "multi_ack"))
 418                        multi_ack = 1;
 419                if (strstr(line+45, "thin-pack"))
 420                        use_thin_pack = 1;
 421                if (strstr(line+45, "side-band"))
 422                        use_sideband = 1;
 423
 424                /* We have sent all our refs already, and the other end
 425                 * should have chosen out of them; otherwise they are
 426                 * asking for nonsense.
 427                 *
 428                 * Hmph.  We may later want to allow "want" line that
 429                 * asks for something like "master~10" (symbolic)...
 430                 * would it make sense?  I don't know.
 431                 */
 432                o = lookup_object(sha1_buf);
 433                if (!o || !(o->flags & OUR_REF))
 434                        die("git-upload-pack: not our ref %s", line+5);
 435                if (!(o->flags & WANTED)) {
 436                        o->flags |= WANTED;
 437                        needs++;
 438                }
 439        }
 440}
 441
 442static int send_ref(const char *refname, const unsigned char *sha1)
 443{
 444        static char *capabilities = "multi_ack thin-pack side-band";
 445        struct object *o = parse_object(sha1);
 446
 447        if (!o)
 448                die("git-upload-pack: cannot find object %s:", sha1_to_hex(sha1));
 449
 450        if (capabilities)
 451                packet_write(1, "%s %s%c%s\n", sha1_to_hex(sha1), refname,
 452                        0, capabilities);
 453        else
 454                packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname);
 455        capabilities = NULL;
 456        if (!(o->flags & OUR_REF)) {
 457                o->flags |= OUR_REF;
 458                nr_our_refs++;
 459        }
 460        if (o->type == TYPE_TAG) {
 461                o = deref_tag(o, refname, 0);
 462                packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
 463        }
 464        return 0;
 465}
 466
 467static int upload_pack(void)
 468{
 469        reset_timeout();
 470        head_ref(send_ref);
 471        for_each_ref(send_ref);
 472        packet_flush(1);
 473        nr_needs = receive_needs();
 474        if (!nr_needs)
 475                return 0;
 476        get_common_commits();
 477        create_pack_file();
 478        return 0;
 479}
 480
 481int main(int argc, char **argv)
 482{
 483        char *dir;
 484        int i;
 485        int strict = 0;
 486
 487        for (i = 1; i < argc; i++) {
 488                char *arg = argv[i];
 489
 490                if (arg[0] != '-')
 491                        break;
 492                if (!strcmp(arg, "--strict")) {
 493                        strict = 1;
 494                        continue;
 495                }
 496                if (!strncmp(arg, "--timeout=", 10)) {
 497                        timeout = atoi(arg+10);
 498                        continue;
 499                }
 500                if (!strcmp(arg, "--")) {
 501                        i++;
 502                        break;
 503                }
 504        }
 505        
 506        if (i != argc-1)
 507                usage(upload_pack_usage);
 508        dir = argv[i];
 509
 510        if (!enter_repo(dir, strict))
 511                die("'%s': unable to chdir or not a git archive", dir);
 512
 513        upload_pack();
 514        return 0;
 515}