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, *ent;
 135
 136                old_commit = (struct commit *)parse_object(old_sha1);
 137                new_commit = (struct commit *)parse_object(new_sha1);
 138                bases = get_merge_bases(old_commit, new_commit, 1);
 139                for (ent = bases; ent; ent = ent->next)
 140                        if (!hashcmp(old_sha1, ent->item->object.sha1))
 141                                break;
 142                free_commit_list(bases);
 143                if (!ent)
 144                        return error("denying non-fast forward;"
 145                                     " you should pull first");
 146        }
 147        safe_create_leading_directories(lock_name);
 148
 149        newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
 150        if (newfd < 0) {
 151                cmd->error_string = "can't lock";
 152                return error("unable to create %s (%s)",
 153                             lock_name, strerror(errno));
 154        }
 155
 156        /* Write the ref with an ending '\n' */
 157        new_hex[40] = '\n';
 158        new_hex[41] = 0;
 159        written = write(newfd, new_hex, 41);
 160        /* Remove the '\n' again */
 161        new_hex[40] = 0;
 162
 163        close(newfd);
 164        if (written != 41) {
 165                unlink(lock_name);
 166                cmd->error_string = "can't write";
 167                return error("unable to write %s", lock_name);
 168        }
 169        if (verify_old_ref(name, old_hex) < 0) {
 170                unlink(lock_name);
 171                cmd->error_string = "raced";
 172                return error("%s changed during push", name);
 173        }
 174        if (run_update_hook(name, old_hex, new_hex)) {
 175                unlink(lock_name);
 176                cmd->error_string = "hook declined";
 177                return error("hook declined to update %s", name);
 178        }
 179        else if (rename(lock_name, name) < 0) {
 180                unlink(lock_name);
 181                cmd->error_string = "can't rename";
 182                return error("unable to replace %s", name);
 183        }
 184        else {
 185                fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
 186                return 0;
 187        }
 188}
 189
 190static char update_post_hook[] = "hooks/post-update";
 191
 192static void run_update_post_hook(struct command *cmd)
 193{
 194        struct command *cmd_p;
 195        int argc;
 196        const char **argv;
 197
 198        if (access(update_post_hook, X_OK) < 0)
 199                return;
 200        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 201                if (cmd_p->error_string)
 202                        continue;
 203                argc++;
 204        }
 205        argv = xmalloc(sizeof(*argv) * (1 + argc));
 206        argv[0] = update_post_hook;
 207
 208        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 209                char *p;
 210                if (cmd_p->error_string)
 211                        continue;
 212                p = xmalloc(strlen(cmd_p->ref_name) + 1);
 213                strcpy(p, cmd_p->ref_name);
 214                argv[argc] = p;
 215                argc++;
 216        }
 217        argv[argc] = NULL;
 218        run_command_v_opt(argc, argv, RUN_COMMAND_NO_STDIO);
 219}
 220
 221/*
 222 * This gets called after(if) we've successfully
 223 * unpacked the data payload.
 224 */
 225static void execute_commands(void)
 226{
 227        struct command *cmd = commands;
 228
 229        while (cmd) {
 230                update(cmd);
 231                cmd = cmd->next;
 232        }
 233        run_update_post_hook(commands);
 234}
 235
 236static void read_head_info(void)
 237{
 238        struct command **p = &commands;
 239        for (;;) {
 240                static char line[1000];
 241                unsigned char old_sha1[20], new_sha1[20];
 242                struct command *cmd;
 243                char *refname;
 244                int len, reflen;
 245
 246                len = packet_read_line(0, line, sizeof(line));
 247                if (!len)
 248                        break;
 249                if (line[len-1] == '\n')
 250                        line[--len] = 0;
 251                if (len < 83 ||
 252                    line[40] != ' ' ||
 253                    line[81] != ' ' ||
 254                    get_sha1_hex(line, old_sha1) ||
 255                    get_sha1_hex(line + 41, new_sha1))
 256                        die("protocol error: expected old/new/ref, got '%s'",
 257                            line);
 258
 259                refname = line + 82;
 260                reflen = strlen(refname);
 261                if (reflen + 82 < len) {
 262                        if (strstr(refname + reflen + 1, "report-status"))
 263                                report_status = 1;
 264                }
 265                cmd = xmalloc(sizeof(struct command) + len - 80);
 266                hashcpy(cmd->old_sha1, old_sha1);
 267                hashcpy(cmd->new_sha1, new_sha1);
 268                memcpy(cmd->ref_name, line + 82, len - 81);
 269                cmd->error_string = "n/a (unpacker error)";
 270                cmd->next = NULL;
 271                *p = cmd;
 272                p = &cmd->next;
 273        }
 274}
 275
 276static const char *unpack(int *error_code)
 277{
 278        int code = run_command_v_opt(1, unpacker, RUN_GIT_CMD);
 279
 280        *error_code = 0;
 281        switch (code) {
 282        case 0:
 283                return NULL;
 284        case -ERR_RUN_COMMAND_FORK:
 285                return "unpack fork failed";
 286        case -ERR_RUN_COMMAND_EXEC:
 287                return "unpack execute failed";
 288        case -ERR_RUN_COMMAND_WAITPID:
 289                return "waitpid failed";
 290        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 291                return "waitpid is confused";
 292        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 293                return "unpacker died of signal";
 294        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 295                return "unpacker died strangely";
 296        default:
 297                *error_code = -code;
 298                return "unpacker exited with error code";
 299        }
 300}
 301
 302static void report(const char *unpack_status)
 303{
 304        struct command *cmd;
 305        packet_write(1, "unpack %s\n",
 306                     unpack_status ? unpack_status : "ok");
 307        for (cmd = commands; cmd; cmd = cmd->next) {
 308                if (!cmd->error_string)
 309                        packet_write(1, "ok %s\n",
 310                                     cmd->ref_name);
 311                else
 312                        packet_write(1, "ng %s %s\n",
 313                                     cmd->ref_name, cmd->error_string);
 314        }
 315        packet_flush(1);
 316}
 317
 318int main(int argc, char **argv)
 319{
 320        int i;
 321        char *dir = NULL;
 322
 323        argv++;
 324        for (i = 1; i < argc; i++) {
 325                char *arg = *argv++;
 326
 327                if (*arg == '-') {
 328                        /* Do flag handling here */
 329                        usage(receive_pack_usage);
 330                }
 331                if (dir)
 332                        usage(receive_pack_usage);
 333                dir = arg;
 334        }
 335        if (!dir)
 336                usage(receive_pack_usage);
 337
 338        if(!enter_repo(dir, 0))
 339                die("'%s': unable to chdir or not a git archive", dir);
 340
 341        write_head_info();
 342
 343        /* EOF */
 344        packet_flush(1);
 345
 346        read_head_info();
 347        if (commands) {
 348                int code;
 349                const char *unpack_status = unpack(&code);
 350                if (!unpack_status)
 351                        execute_commands();
 352                if (report_status)
 353                        report(unpack_status);
 354        }
 355        return 0;
 356}