Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "pack.h"
   3#include "refs.h"
   4#include "pkt-line.h"
   5#include "run-command.h"
   6#include "exec_cmd.h"
   7#include "commit.h"
   8#include "object.h"
   9
  10static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
  11
  12static int deny_non_fast_forwards = 0;
  13static int receive_unpack_limit = -1;
  14static int transfer_unpack_limit = -1;
  15static int unpack_limit = 100;
  16static int report_status;
  17
  18static char capabilities[] = " report-status delete-refs ";
  19static int capabilities_sent;
  20
  21static int receive_pack_config(const char *var, const char *value)
  22{
  23        if (strcmp(var, "receive.denynonfastforwards") == 0) {
  24                deny_non_fast_forwards = git_config_bool(var, value);
  25                return 0;
  26        }
  27
  28        if (strcmp(var, "receive.unpacklimit") == 0) {
  29                receive_unpack_limit = git_config_int(var, value);
  30                return 0;
  31        }
  32
  33        if (strcmp(var, "transfer.unpacklimit") == 0) {
  34                transfer_unpack_limit = git_config_int(var, value);
  35                return 0;
  36        }
  37
  38        return git_default_config(var, value);
  39}
  40
  41static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  42{
  43        if (capabilities_sent)
  44                packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  45        else
  46                packet_write(1, "%s %s%c%s\n",
  47                             sha1_to_hex(sha1), path, 0, capabilities);
  48        capabilities_sent = 1;
  49        return 0;
  50}
  51
  52static void write_head_info(void)
  53{
  54        for_each_ref(show_ref, NULL);
  55        if (!capabilities_sent)
  56                show_ref("capabilities^{}", null_sha1, 0, NULL);
  57
  58}
  59
  60struct command {
  61        struct command *next;
  62        const char *error_string;
  63        unsigned char old_sha1[20];
  64        unsigned char new_sha1[20];
  65        char ref_name[FLEX_ARRAY]; /* more */
  66};
  67
  68static struct command *commands;
  69
  70static char update_hook[] = "hooks/update";
  71
  72static int run_update_hook(const char *refname,
  73                           char *old_hex, char *new_hex)
  74{
  75        int code;
  76
  77        if (access(update_hook, X_OK) < 0)
  78                return 0;
  79        code = run_command_opt(RUN_COMMAND_NO_STDIN
  80                | RUN_COMMAND_STDOUT_TO_STDERR,
  81                update_hook, refname, old_hex, new_hex, NULL);
  82        switch (code) {
  83        case 0:
  84                return 0;
  85        case -ERR_RUN_COMMAND_FORK:
  86                return error("hook fork failed");
  87        case -ERR_RUN_COMMAND_EXEC:
  88                return error("hook execute failed");
  89        case -ERR_RUN_COMMAND_WAITPID:
  90                return error("waitpid failed");
  91        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
  92                return error("waitpid is confused");
  93        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
  94                return error("%s died of signal", update_hook);
  95        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
  96                return error("%s died strangely", update_hook);
  97        default:
  98                error("%s exited with error code %d", update_hook, -code);
  99                return -code;
 100        }
 101}
 102
 103static int update(struct command *cmd)
 104{
 105        const char *name = cmd->ref_name;
 106        unsigned char *old_sha1 = cmd->old_sha1;
 107        unsigned char *new_sha1 = cmd->new_sha1;
 108        char new_hex[41], old_hex[41];
 109        struct ref_lock *lock;
 110
 111        cmd->error_string = NULL;
 112        if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
 113                cmd->error_string = "funny refname";
 114                return error("refusing to create funny ref '%s' locally",
 115                             name);
 116        }
 117
 118        strcpy(new_hex, sha1_to_hex(new_sha1));
 119        strcpy(old_hex, sha1_to_hex(old_sha1));
 120
 121        if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
 122                cmd->error_string = "bad pack";
 123                return error("unpack should have generated %s, "
 124                             "but I can't find it!", new_hex);
 125        }
 126        if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 127            !is_null_sha1(old_sha1) &&
 128            !prefixcmp(name, "refs/heads/")) {
 129                struct commit *old_commit, *new_commit;
 130                struct commit_list *bases, *ent;
 131
 132                old_commit = (struct commit *)parse_object(old_sha1);
 133                new_commit = (struct commit *)parse_object(new_sha1);
 134                bases = get_merge_bases(old_commit, new_commit, 1);
 135                for (ent = bases; ent; ent = ent->next)
 136                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 137                                break;
 138                free_commit_list(bases);
 139                if (!ent)
 140                        return error("denying non-fast forward;"
 141                                     " you should pull first");
 142        }
 143        if (run_update_hook(name, old_hex, new_hex)) {
 144                cmd->error_string = "hook declined";
 145                return error("hook declined to update %s", name);
 146        }
 147
 148        if (is_null_sha1(new_sha1)) {
 149                if (delete_ref(name, old_sha1)) {
 150                        cmd->error_string = "failed to delete";
 151                        return error("failed to delete %s", name);
 152                }
 153                fprintf(stderr, "%s: %s -> deleted\n", name, old_hex);
 154        }
 155        else {
 156                lock = lock_any_ref_for_update(name, old_sha1);
 157                if (!lock) {
 158                        cmd->error_string = "failed to lock";
 159                        return error("failed to lock %s", name);
 160                }
 161                if (write_ref_sha1(lock, new_sha1, "push")) {
 162                        cmd->error_string = "failed to write";
 163                        return -1; /* error() already called */
 164                }
 165                fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
 166        }
 167        return 0;
 168}
 169
 170static char update_post_hook[] = "hooks/post-update";
 171
 172static void run_update_post_hook(struct command *cmd)
 173{
 174        struct command *cmd_p;
 175        int argc;
 176        const char **argv;
 177
 178        if (access(update_post_hook, X_OK) < 0)
 179                return;
 180        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 181                if (cmd_p->error_string)
 182                        continue;
 183                argc++;
 184        }
 185        argv = xmalloc(sizeof(*argv) * (1 + argc));
 186        argv[0] = update_post_hook;
 187
 188        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 189                char *p;
 190                if (cmd_p->error_string)
 191                        continue;
 192                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 193                strcpy(p, cmd_p->ref_name);
 194                argv[argc] = p;
 195                argc++;
 196        }
 197        argv[argc] = NULL;
 198        run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 199                | RUN_COMMAND_STDOUT_TO_STDERR);
 200}
 201
 202/*
 203 * This gets called after(if) we've successfully
 204 * unpacked the data payload.
 205 */
 206static void execute_commands(void)
 207{
 208        struct command *cmd = commands;
 209
 210        while (cmd) {
 211                update(cmd);
 212                cmd = cmd->next;
 213        }
 214        run_update_post_hook(commands);
 215}
 216
 217static void read_head_info(void)
 218{
 219        struct command **p = &commands;
 220        for (;;) {
 221                static char line[1000];
 222                unsigned char old_sha1[20], new_sha1[20];
 223                struct command *cmd;
 224                char *refname;
 225                int len, reflen;
 226
 227                len = packet_read_line(0, line, sizeof(line));
 228                if (!len)
 229                        break;
 230                if (line[len-1] == '\n')
 231                        line[--len] = 0;
 232                if (len < 83 ||
 233                    line[40] != ' ' ||
 234                    line[81] != ' ' ||
 235                    get_sha1_hex(line, old_sha1) ||
 236                    get_sha1_hex(line + 41, new_sha1))
 237                        die("protocol error: expected old/new/ref, got '%s'",
 238                            line);
 239
 240                refname = line + 82;
 241                reflen = strlen(refname);
 242                if (reflen + 82 < len) {
 243                        if (strstr(refname + reflen + 1, "report-status"))
 244                                report_status = 1;
 245                }
 246                cmd = xmalloc(sizeof(struct command) + len - 80);
 247                hashcpy(cmd->old_sha1, old_sha1);
 248                hashcpy(cmd->new_sha1, new_sha1);
 249                memcpy(cmd->ref_name, line + 82, len - 81);
 250                cmd->error_string = "n/a (unpacker error)";
 251                cmd->next = NULL;
 252                *p = cmd;
 253                p = &cmd->next;
 254        }
 255}
 256
 257static const char *parse_pack_header(struct pack_header *hdr)
 258{
 259        switch (read_pack_header(0, hdr)) {
 260        case PH_ERROR_EOF:
 261                return "eof before pack header was fully read";
 262
 263        case PH_ERROR_PACK_SIGNATURE:
 264                return "protocol error (pack signature mismatch detected)";
 265
 266        case PH_ERROR_PROTOCOL:
 267                return "protocol error (pack version unsupported)";
 268
 269        default:
 270                return "unknown error in parse_pack_header";
 271
 272        case 0:
 273                return NULL;
 274        }
 275}
 276
 277static const char *pack_lockfile;
 278
 279static const char *unpack(void)
 280{
 281        struct pack_header hdr;
 282        const char *hdr_err;
 283        char hdr_arg[38];
 284
 285        hdr_err = parse_pack_header(&hdr);
 286        if (hdr_err)
 287                return hdr_err;
 288        snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
 289                        ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 290
 291        if (ntohl(hdr.hdr_entries) < unpack_limit) {
 292                int code;
 293                const char *unpacker[3];
 294                unpacker[0] = "unpack-objects";
 295                unpacker[1] = hdr_arg;
 296                unpacker[2] = NULL;
 297                code = run_command_v_opt(unpacker, RUN_GIT_CMD);
 298                switch (code) {
 299                case 0:
 300                        return NULL;
 301                case -ERR_RUN_COMMAND_FORK:
 302                        return "unpack fork failed";
 303                case -ERR_RUN_COMMAND_EXEC:
 304                        return "unpack execute failed";
 305                case -ERR_RUN_COMMAND_WAITPID:
 306                        return "waitpid failed";
 307                case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 308                        return "waitpid is confused";
 309                case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 310                        return "unpacker died of signal";
 311                case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 312                        return "unpacker died strangely";
 313                default:
 314                        return "unpacker exited with error code";
 315                }
 316        } else {
 317                const char *keeper[6];
 318                int fd[2], s, len, status;
 319                pid_t pid;
 320                char keep_arg[256];
 321                char packname[46];
 322
 323                s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
 324                if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 325                        strcpy(keep_arg + s, "localhost");
 326
 327                keeper[0] = "index-pack";
 328                keeper[1] = "--stdin";
 329                keeper[2] = "--fix-thin";
 330                keeper[3] = hdr_arg;
 331                keeper[4] = keep_arg;
 332                keeper[5] = NULL;
 333
 334                if (pipe(fd) < 0)
 335                        return "index-pack pipe failed";
 336                pid = fork();
 337                if (pid < 0)
 338                        return "index-pack fork failed";
 339                if (!pid) {
 340                        dup2(fd[1], 1);
 341                        close(fd[1]);
 342                        close(fd[0]);
 343                        execv_git_cmd(keeper);
 344                        die("execv of index-pack failed");
 345                }
 346                close(fd[1]);
 347
 348                /*
 349                 * The first thing we expects from index-pack's output
 350                 * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
 351                 * %40s is the newly created pack SHA1 name.  In the "keep"
 352                 * case, we need it to remove the corresponding .keep file
 353                 * later on.  If we don't get that then tough luck with it.
 354                 */
 355                for (len = 0;
 356                     len < 46 && (s = xread(fd[0], packname+len, 46-len)) > 0;
 357                     len += s);
 358                close(fd[0]);
 359                if (len == 46 && packname[45] == '\n' &&
 360                    memcmp(packname, "keep\t", 5) == 0) {
 361                        char path[PATH_MAX];
 362                        packname[45] = 0;
 363                        snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
 364                                 get_object_directory(), packname + 5);
 365                        pack_lockfile = xstrdup(path);
 366                }
 367
 368                /* Then wrap our index-pack process. */
 369                while (waitpid(pid, &status, 0) < 0)
 370                        if (errno != EINTR)
 371                                return "waitpid failed";
 372                if (WIFEXITED(status)) {
 373                        int code = WEXITSTATUS(status);
 374                        if (code)
 375                                return "index-pack exited with error code";
 376                        reprepare_packed_git();
 377                        return NULL;
 378                }
 379                return "index-pack abnormal exit";
 380        }
 381}
 382
 383static void report(const char *unpack_status)
 384{
 385        struct command *cmd;
 386        packet_write(1, "unpack %s\n",
 387                     unpack_status ? unpack_status : "ok");
 388        for (cmd = commands; cmd; cmd = cmd->next) {
 389                if (!cmd->error_string)
 390                        packet_write(1, "ok %s\n",
 391                                     cmd->ref_name);
 392                else
 393                        packet_write(1, "ng %s %s\n",
 394                                     cmd->ref_name, cmd->error_string);
 395        }
 396        packet_flush(1);
 397}
 398
 399static int delete_only(struct command *cmd)
 400{
 401        while (cmd) {
 402                if (!is_null_sha1(cmd->new_sha1))
 403                        return 0;
 404                cmd = cmd->next;
 405        }
 406        return 1;
 407}
 408
 409int main(int argc, char **argv)
 410{
 411        int i;
 412        char *dir = NULL;
 413
 414        argv++;
 415        for (i = 1; i < argc; i++) {
 416                char *arg = *argv++;
 417
 418                if (*arg == '-') {
 419                        /* Do flag handling here */
 420                        usage(receive_pack_usage);
 421                }
 422                if (dir)
 423                        usage(receive_pack_usage);
 424                dir = arg;
 425        }
 426        if (!dir)
 427                usage(receive_pack_usage);
 428
 429        if (!enter_repo(dir, 0))
 430                die("'%s': unable to chdir or not a git archive", dir);
 431
 432        if (is_repository_shallow())
 433                die("attempt to push into a shallow repository");
 434
 435        git_config(receive_pack_config);
 436
 437        if (0 <= transfer_unpack_limit)
 438                unpack_limit = transfer_unpack_limit;
 439        else if (0 <= receive_unpack_limit)
 440                unpack_limit = receive_unpack_limit;
 441
 442        write_head_info();
 443
 444        /* EOF */
 445        packet_flush(1);
 446
 447        read_head_info();
 448        if (commands) {
 449                const char *unpack_status = NULL;
 450
 451                if (!delete_only(commands))
 452                        unpack_status = unpack();
 453                if (!unpack_status)
 454                        execute_commands();
 455                if (pack_lockfile)
 456                        unlink(pack_lockfile);
 457                if (report_status)
 458                        report(unpack_status);
 459        }
 460        return 0;
 461}