Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "refs.h"
   3#include "pkt-line.h"
   4#include "run-command.h"
   5#include "commit.h"
   6#include "object.h"
   7
   8static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
   9
  10static const char *unpacker[] = { "unpack-objects", NULL };
  11
  12static int report_status;
  13
  14static char capabilities[] = "report-status";
  15static int capabilities_sent;
  16
  17static int show_ref(const char *path, const unsigned char *sha1)
  18{
  19        if (capabilities_sent)
  20                packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  21        else
  22                packet_write(1, "%s %s%c%s\n",
  23                             sha1_to_hex(sha1), path, 0, capabilities);
  24        capabilities_sent = 1;
  25        return 0;
  26}
  27
  28static void write_head_info(void)
  29{
  30        for_each_ref(show_ref);
  31        if (!capabilities_sent)
  32                show_ref("capabilities^{}", null_sha1);
  33
  34}
  35
  36struct command {
  37        struct command *next;
  38        const char *error_string;
  39        unsigned char old_sha1[20];
  40        unsigned char new_sha1[20];
  41        char ref_name[FLEX_ARRAY]; /* more */
  42};
  43
  44static struct command *commands;
  45
  46static int is_all_zeroes(const char *hex)
  47{
  48        int i;
  49        for (i = 0; i < 40; i++)
  50                if (*hex++ != '0')
  51                        return 0;
  52        return 1;
  53}
  54
  55static int verify_old_ref(const char *name, char *hex_contents)
  56{
  57        int fd, ret;
  58        char buffer[60];
  59
  60        if (is_all_zeroes(hex_contents))
  61                return 0;
  62        fd = open(name, O_RDONLY);
  63        if (fd < 0)
  64                return -1;
  65        ret = read(fd, buffer, 40);
  66        close(fd);
  67        if (ret != 40)
  68                return -1;
  69        if (memcmp(buffer, hex_contents, 40))
  70                return -1;
  71        return 0;
  72}
  73
  74static char update_hook[] = "hooks/update";
  75
  76static int run_update_hook(const char *refname,
  77                           char *old_hex, char *new_hex)
  78{
  79        int code;
  80
  81        if (access(update_hook, X_OK) < 0)
  82                return 0;
  83        code = run_command(update_hook, refname, old_hex, new_hex, NULL);
  84        switch (code) {
  85        case 0:
  86                return 0;
  87        case -ERR_RUN_COMMAND_FORK:
  88                return error("hook fork failed");
  89        case -ERR_RUN_COMMAND_EXEC:
  90                return error("hook execute failed");
  91        case -ERR_RUN_COMMAND_WAITPID:
  92                return error("waitpid failed");
  93        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
  94                return error("waitpid is confused");
  95        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
  96                return error("%s died of signal", update_hook);
  97        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
  98                return error("%s died strangely", update_hook);
  99        default:
 100                error("%s exited with error code %d", update_hook, -code);
 101                return -code;
 102        }
 103}
 104
 105static int update(struct command *cmd)
 106{
 107        const char *name = cmd->ref_name;
 108        unsigned char *old_sha1 = cmd->old_sha1;
 109        unsigned char *new_sha1 = cmd->new_sha1;
 110        char new_hex[60], *old_hex, *lock_name;
 111        int newfd, namelen, written;
 112
 113        cmd->error_string = NULL;
 114        if (!strncmp(name, "refs/", 5) && check_ref_format(name + 5)) {
 115                cmd->error_string = "funny refname";
 116                return error("refusing to create funny ref '%s' locally",
 117                             name);
 118        }
 119
 120        namelen = strlen(name);
 121        lock_name = xmalloc(namelen + 10);
 122        memcpy(lock_name, name, namelen);
 123        memcpy(lock_name + namelen, ".lock", 6);
 124
 125        strcpy(new_hex, sha1_to_hex(new_sha1));
 126        old_hex = sha1_to_hex(old_sha1);
 127        if (!has_sha1_file(new_sha1)) {
 128                cmd->error_string = "bad pack";
 129                return error("unpack should have generated %s, "
 130                             "but I can't find it!", new_hex);
 131        }
 132        if (deny_non_fast_forwards && !is_null_sha1(old_sha1)) {
 133                struct commit *old_commit, *new_commit;
 134                struct commit_list *bases;
 135
 136                old_commit = (struct commit *)parse_object(old_sha1);
 137                new_commit = (struct commit *)parse_object(new_sha1);
 138                for (bases = get_merge_bases(old_commit, new_commit, 1);
 139                                bases; bases = bases->next)
 140                        if (!hashcmp(old_sha1, bases->item->object.sha1))
 141                                break;
 142                if (!bases)
 143                        return error("denying non-fast forward;"
 144                                        " you should pull first");
 145        }
 146        safe_create_leading_directories(lock_name);
 147
 148        newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
 149        if (newfd < 0) {
 150                cmd->error_string = "can't lock";
 151                return error("unable to create %s (%s)",
 152                             lock_name, strerror(errno));
 153        }
 154
 155        /* Write the ref with an ending '\n' */
 156        new_hex[40] = '\n';
 157        new_hex[41] = 0;
 158        written = write(newfd, new_hex, 41);
 159        /* Remove the '\n' again */
 160        new_hex[40] = 0;
 161
 162        close(newfd);
 163        if (written != 41) {
 164                unlink(lock_name);
 165                cmd->error_string = "can't write";
 166                return error("unable to write %s", lock_name);
 167        }
 168        if (verify_old_ref(name, old_hex) < 0) {
 169                unlink(lock_name);
 170                cmd->error_string = "raced";
 171                return error("%s changed during push", name);
 172        }
 173        if (run_update_hook(name, old_hex, new_hex)) {
 174                unlink(lock_name);
 175                cmd->error_string = "hook declined";
 176                return error("hook declined to update %s", name);
 177        }
 178        else if (rename(lock_name, name) < 0) {
 179                unlink(lock_name);
 180                cmd->error_string = "can't rename";
 181                return error("unable to replace %s", name);
 182        }
 183        else {
 184                fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
 185                return 0;
 186        }
 187}
 188
 189static char update_post_hook[] = "hooks/post-update";
 190
 191static void run_update_post_hook(struct command *cmd)
 192{
 193        struct command *cmd_p;
 194        int argc;
 195        const char **argv;
 196
 197        if (access(update_post_hook, X_OK) < 0)
 198                return;
 199        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 200                if (cmd_p->error_string)
 201                        continue;
 202                argc++;
 203        }
 204        argv = xmalloc(sizeof(*argv) * (1 + argc));
 205        argv[0] = update_post_hook;
 206
 207        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 208                char *p;
 209                if (cmd_p->error_string)
 210                        continue;
 211                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 212                strcpy(p, cmd_p->ref_name);
 213                argv[argc] = p;
 214                argc++;
 215        }
 216        argv[argc] = NULL;
 217        run_command_v_opt(argc, argv, RUN_COMMAND_NO_STDIO);
 218}
 219
 220/*
 221 * This gets called after(if) we've successfully
 222 * unpacked the data payload.
 223 */
 224static void execute_commands(void)
 225{
 226        struct command *cmd = commands;
 227
 228        while (cmd) {
 229                update(cmd);
 230                cmd = cmd->next;
 231        }
 232        run_update_post_hook(commands);
 233}
 234
 235static void read_head_info(void)
 236{
 237        struct command **p = &commands;
 238        for (;;) {
 239                static char line[1000];
 240                unsigned char old_sha1[20], new_sha1[20];
 241                struct command *cmd;
 242                char *refname;
 243                int len, reflen;
 244
 245                len = packet_read_line(0, line, sizeof(line));
 246                if (!len)
 247                        break;
 248                if (line[len-1] == '\n')
 249                        line[--len] = 0;
 250                if (len < 83 ||
 251                    line[40] != ' ' ||
 252                    line[81] != ' ' ||
 253                    get_sha1_hex(line, old_sha1) ||
 254                    get_sha1_hex(line + 41, new_sha1))
 255                        die("protocol error: expected old/new/ref, got '%s'",
 256                            line);
 257
 258                refname = line + 82;
 259                reflen = strlen(refname);
 260                if (reflen + 82 < len) {
 261                        if (strstr(refname + reflen + 1, "report-status"))
 262                                report_status = 1;
 263                }
 264                cmd = xmalloc(sizeof(struct command) + len - 80);
 265                hashcpy(cmd->old_sha1, old_sha1);
 266                hashcpy(cmd->new_sha1, new_sha1);
 267                memcpy(cmd->ref_name, line + 82, len - 81);
 268                cmd->error_string = "n/a (unpacker error)";
 269                cmd->next = NULL;
 270                *p = cmd;
 271                p = &cmd->next;
 272        }
 273}
 274
 275static const char *unpack(int *error_code)
 276{
 277        int code = run_command_v_opt(1, unpacker, RUN_GIT_CMD);
 278
 279        *error_code = 0;
 280        switch (code) {
 281        case 0:
 282                return NULL;
 283        case -ERR_RUN_COMMAND_FORK:
 284                return "unpack fork failed";
 285        case -ERR_RUN_COMMAND_EXEC:
 286                return "unpack execute failed";
 287        case -ERR_RUN_COMMAND_WAITPID:
 288                return "waitpid failed";
 289        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 290                return "waitpid is confused";
 291        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 292                return "unpacker died of signal";
 293        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 294                return "unpacker died strangely";
 295        default:
 296                *error_code = -code;
 297                return "unpacker exited with error code";
 298        }
 299}
 300
 301static void report(const char *unpack_status)
 302{
 303        struct command *cmd;
 304        packet_write(1, "unpack %s\n",
 305                     unpack_status ? unpack_status : "ok");
 306        for (cmd = commands; cmd; cmd = cmd->next) {
 307                if (!cmd->error_string)
 308                        packet_write(1, "ok %s\n",
 309                                     cmd->ref_name);
 310                else
 311                        packet_write(1, "ng %s %s\n",
 312                                     cmd->ref_name, cmd->error_string);
 313        }
 314        packet_flush(1);
 315}
 316
 317int main(int argc, char **argv)
 318{
 319        int i;
 320        char *dir = NULL;
 321
 322        argv++;
 323        for (i = 1; i < argc; i++) {
 324                char *arg = *argv++;
 325
 326                if (*arg == '-') {
 327                        /* Do flag handling here */
 328                        usage(receive_pack_usage);
 329                }
 330                if (dir)
 331                        usage(receive_pack_usage);
 332                dir = arg;
 333        }
 334        if (!dir)
 335                usage(receive_pack_usage);
 336
 337        if(!enter_repo(dir, 0))
 338                die("'%s': unable to chdir or not a git archive", dir);
 339
 340        write_head_info();
 341
 342        /* EOF */
 343        packet_flush(1);
 344
 345        read_head_info();
 346        if (commands) {
 347                int code;
 348                const char *unpack_status = unpack(&code);
 349                if (!unpack_status)
 350                        execute_commands();
 351                if (report_status)
 352                        report(unpack_status);
 353        }
 354        return 0;
 355}