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