receive-pack.c

   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
   8 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
   9
  10 static const char *unpacker[] = { "unpack-objects", NULL };
  11
  12 static int deny_non_fast_forwards = 0;
  13 static int report_status;
  14
  15 static char capabilities[] = "report-status";
  16 static int capabilities_sent;
  17
  18 static int receive_pack_config(const char *var, const char *value)
  19 {
  20         git_default_config(var, value);
  21
  22         if (strcmp(var, "receive.denynonfastforwards") == 0)
  23         {
  24                 deny_non_fast_forwards = git_config_bool(var, value);
  25                 return 0;
  26         }
  27
  28         return 0;
  29 }
  30
  31 static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
  32 {
  33         if (capabilities_sent)
  34                 packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
  35         else
  36                 packet_write(1, "%s %s%c%s\n",
  37                              sha1_to_hex(sha1), path, 0, capabilities);
  38         capabilities_sent = 1;
  39         return 0;
  40 }
  41
  42 static void write_head_info(void)
  43 {
  44         for_each_ref(show_ref, NULL);
  45         if (!capabilities_sent)
  46                 show_ref("capabilities^{}", null_sha1, 0, NULL);
  47
  48 }
  49
  50 struct command {
  51         struct command *next;
  52         const char *error_string;
  53         unsigned char old_sha1[20];
  54         unsigned char new_sha1[20];
  55         char ref_name[FLEX_ARRAY]; /* more */
  56 };
  57
  58 static struct command *commands;
  59
  60 static char update_hook[] = "hooks/update";
  61
  62 static int run_update_hook(const char *refname,
  63                            char *old_hex, char *new_hex)
  64 {
  65         int code;
  66
  67         if (access(update_hook, X_OK) < 0)
  68                 return 0;
  69         code = run_command(update_hook, refname, old_hex, new_hex, NULL);
  70         switch (code) {
  71         case 0:
  72                 return 0;
  73         case -ERR_RUN_COMMAND_FORK:
  74                 return error("hook fork failed");
  75         case -ERR_RUN_COMMAND_EXEC:
  76                 return error("hook execute failed");
  77         case -ERR_RUN_COMMAND_WAITPID:
  78                 return error("waitpid failed");
  79         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
  80                 return error("waitpid is confused");
  81         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
  82                 return error("%s died of signal", update_hook);
  83         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
  84                 return error("%s died strangely", update_hook);
  85         default:
  86                 error("%s exited with error code %d", update_hook, -code);
  87                 return -code;
  88         }
  89 }
  90
  91 static int update(struct command *cmd)
  92 {
  93         const char *name = cmd->ref_name;
  94         unsigned char *old_sha1 = cmd->old_sha1;
  95         unsigned char *new_sha1 = cmd->new_sha1;
  96         char new_hex[41], old_hex[41];
  97         struct ref_lock *lock;
  98
  99         cmd->error_string = NULL;
 100         if (!strncmp(name, "refs/", 5) && check_ref_format(name + 5)) {
 101                 cmd->error_string = "funny refname";
 102                 return error("refusing to create funny ref '%s' locally",
 103                              name);
 104         }
 105
 106         strcpy(new_hex, sha1_to_hex(new_sha1));
 107         strcpy(old_hex, sha1_to_hex(old_sha1));
 108         if (!has_sha1_file(new_sha1)) {
 109                 cmd->error_string = "bad pack";
 110                 return error("unpack should have generated %s, "
 111                              "but I can't find it!", new_hex);
 112         }
 113         if (deny_non_fast_forwards && !is_null_sha1(old_sha1)) {
 114                 struct commit *old_commit, *new_commit;
 115                 struct commit_list *bases, *ent;
 116
 117                 old_commit = (struct commit *)parse_object(old_sha1);
 118                 new_commit = (struct commit *)parse_object(new_sha1);
 119                 bases = get_merge_bases(old_commit, new_commit, 1);
 120                 for (ent = bases; ent; ent = ent->next)
 121                         if (!hashcmp(old_sha1, ent->item->object.sha1))
 122                                 break;
 123                 free_commit_list(bases);
 124                 if (!ent)
 125                         return error("denying non-fast forward;"
 126                                      " you should pull first");
 127         }
 128         if (run_update_hook(name, old_hex, new_hex)) {
 129                 cmd->error_string = "hook declined";
 130                 return error("hook declined to update %s", name);
 131         }
 132
 133         lock = lock_any_ref_for_update(name, old_sha1);
 134         if (!lock) {
 135                 cmd->error_string = "failed to lock";
 136                 return error("failed to lock %s", name);
 137         }
 138         write_ref_sha1(lock, new_sha1, "push");
 139
 140         fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
 141         return 0;
 142 }
 143
 144 static char update_post_hook[] = "hooks/post-update";
 145
 146 static void run_update_post_hook(struct command *cmd)
 147 {
 148         struct command *cmd_p;
 149         int argc;
 150         const char **argv;
 151
 152         if (access(update_post_hook, X_OK) < 0)
 153                 return;
 154         for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 155                 if (cmd_p->error_string)
 156                         continue;
 157                 argc++;
 158         }
 159         argv = xmalloc(sizeof(*argv) * (1 + argc));
 160         argv[0] = update_post_hook;
 161
 162         for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 163                 char *p;
 164                 if (cmd_p->error_string)
 165                         continue;
 166                 p = xmalloc(strlen(cmd_p->ref_name) + 1);
 167                 strcpy(p, cmd_p->ref_name);
 168                 argv[argc] = p;
 169                 argc++;
 170         }
 171         argv[argc] = NULL;
 172         run_command_v_opt(argc, argv, RUN_COMMAND_NO_STDIO);
 173 }
 174
 175 /*
 176  * This gets called after(if) we've successfully
 177  * unpacked the data payload.
 178  */
 179 static void execute_commands(void)
 180 {
 181         struct command *cmd = commands;
 182
 183         while (cmd) {
 184                 update(cmd);
 185                 cmd = cmd->next;
 186         }
 187         run_update_post_hook(commands);
 188 }
 189
 190 static void read_head_info(void)
 191 {
 192         struct command **p = &commands;
 193         for (;;) {
 194                 static char line[1000];
 195                 unsigned char old_sha1[20], new_sha1[20];
 196                 struct command *cmd;
 197                 char *refname;
 198                 int len, reflen;
 199
 200                 len = packet_read_line(0, line, sizeof(line));
 201                 if (!len)
 202                         break;
 203                 if (line[len-1] == '\n')
 204                         line[--len] = 0;
 205                 if (len < 83 ||
 206                     line[40] != ' ' ||
 207                     line[81] != ' ' ||
 208                     get_sha1_hex(line, old_sha1) ||
 209                     get_sha1_hex(line + 41, new_sha1))
 210                         die("protocol error: expected old/new/ref, got '%s'",
 211                             line);
 212
 213                 refname = line + 82;
 214                 reflen = strlen(refname);
 215                 if (reflen + 82 < len) {
 216                         if (strstr(refname + reflen + 1, "report-status"))
 217                                 report_status = 1;
 218                 }
 219                 cmd = xmalloc(sizeof(struct command) + len - 80);
 220                 hashcpy(cmd->old_sha1, old_sha1);
 221                 hashcpy(cmd->new_sha1, new_sha1);
 222                 memcpy(cmd->ref_name, line + 82, len - 81);
 223                 cmd->error_string = "n/a (unpacker error)";
 224                 cmd->next = NULL;
 225                 *p = cmd;
 226                 p = &cmd->next;
 227         }
 228 }
 229
 230 static const char *unpack(void)
 231 {
 232         int code = run_command_v_opt(1, unpacker, RUN_GIT_CMD);
 233
 234         switch (code) {
 235         case 0:
 236                 return NULL;
 237         case -ERR_RUN_COMMAND_FORK:
 238                 return "unpack fork failed";
 239         case -ERR_RUN_COMMAND_EXEC:
 240                 return "unpack execute failed";
 241         case -ERR_RUN_COMMAND_WAITPID:
 242                 return "waitpid failed";
 243         case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
 244                 return "waitpid is confused";
 245         case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
 246                 return "unpacker died of signal";
 247         case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 248                 return "unpacker died strangely";
 249         default:
 250                 return "unpacker exited with error code";
 251         }
 252 }
 253
 254 static void report(const char *unpack_status)
 255 {
 256         struct command *cmd;
 257         packet_write(1, "unpack %s\n",
 258                      unpack_status ? unpack_status : "ok");
 259         for (cmd = commands; cmd; cmd = cmd->next) {
 260                 if (!cmd->error_string)
 261                         packet_write(1, "ok %s\n",
 262                                      cmd->ref_name);
 263                 else
 264                         packet_write(1, "ng %s %s\n",
 265                                      cmd->ref_name, cmd->error_string);
 266         }
 267         packet_flush(1);
 268 }
 269
 270 int main(int argc, char **argv)
 271 {
 272         int i;
 273         char *dir = NULL;
 274
 275         argv++;
 276         for (i = 1; i < argc; i++) {
 277                 char *arg = *argv++;
 278
 279                 if (*arg == '-') {
 280                         /* Do flag handling here */
 281                         usage(receive_pack_usage);
 282                 }
 283                 if (dir)
 284                         usage(receive_pack_usage);
 285                 dir = arg;
 286         }
 287         if (!dir)
 288                 usage(receive_pack_usage);
 289
 290         if (!enter_repo(dir, 0))
 291                 die("'%s': unable to chdir or not a git archive", dir);
 292
 293         setup_ident();
 294         git_config(receive_pack_config);
 295
 296         write_head_info();
 297
 298         /* EOF */
 299         packet_flush(1);
 300
 301         read_head_info();
 302         if (commands) {
 303                 const char *unpack_status = unpack();
 304                 if (!unpack_status)
 305                         execute_commands();
 306                 if (report_status)
 307                         report(unpack_status);
 308         }
 309         return 0;
 310 }