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