Merge branch 'lt/gitlink'
[gitweb.git] / receive-pack.c
index abbcb6af0b61ba5d31db878ccd78e5d7c9c64971..26aa26bcb5089adcf400d12b673519e328b49a23 100644 (file)
@@ -1,17 +1,43 @@
 #include "cache.h"
+#include "pack.h"
 #include "refs.h"
 #include "pkt-line.h"
 #include "run-command.h"
+#include "exec_cmd.h"
+#include "commit.h"
+#include "object.h"
 
 static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
 
-static const char *unpacker[] = { "unpack-objects", NULL };
-
+static int deny_non_fast_forwards = 0;
+static int receive_unpack_limit = -1;
+static int transfer_unpack_limit = -1;
+static int unpack_limit = 100;
 static int report_status;
 
-static char capabilities[] = "report-status";
+static char capabilities[] = " report-status delete-refs ";
 static int capabilities_sent;
 
+static int receive_pack_config(const char *var, const char *value)
+{
+       if (strcmp(var, "receive.denynonfastforwards") == 0) {
+               deny_non_fast_forwards = git_config_bool(var, value);
+               return 0;
+       }
+
+       if (strcmp(var, "receive.unpacklimit") == 0) {
+               receive_unpack_limit = git_config_int(var, value);
+               return 0;
+       }
+
+       if (strcmp(var, "transfer.unpacklimit") == 0) {
+               transfer_unpack_limit = git_config_int(var, value);
+               return 0;
+       }
+
+       return git_default_config(var, value);
+}
+
 static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 {
        if (capabilities_sent)
@@ -41,44 +67,11 @@ struct command {
 
 static struct command *commands;
 
-static int is_all_zeroes(const char *hex)
-{
-       int i;
-       for (i = 0; i < 40; i++)
-               if (*hex++ != '0')
-                       return 0;
-       return 1;
-}
-
-static int verify_old_ref(const char *name, char *hex_contents)
-{
-       int fd, ret;
-       char buffer[60];
-
-       if (is_all_zeroes(hex_contents))
-               return 0;
-       fd = open(name, O_RDONLY);
-       if (fd < 0)
-               return -1;
-       ret = read(fd, buffer, 40);
-       close(fd);
-       if (ret != 40)
-               return -1;
-       if (memcmp(buffer, hex_contents, 40))
-               return -1;
-       return 0;
-}
-
-static char update_hook[] = "hooks/update";
+static const char pre_receive_hook[] = "hooks/pre-receive";
+static const char post_receive_hook[] = "hooks/post-receive";
 
-static int run_update_hook(const char *refname,
-                          char *old_hex, char *new_hex)
+static int hook_status(int code, const char *hook_name)
 {
-       int code;
-
-       if (access(update_hook, X_OK) < 0)
-               return 0;
-       code = run_command(update_hook, refname, old_hex, new_hex, NULL);
        switch (code) {
        case 0:
                return 0;
@@ -86,87 +79,147 @@ static int run_update_hook(const char *refname,
                return error("hook fork failed");
        case -ERR_RUN_COMMAND_EXEC:
                return error("hook execute failed");
+       case -ERR_RUN_COMMAND_PIPE:
+               return error("hook pipe failed");
        case -ERR_RUN_COMMAND_WAITPID:
                return error("waitpid failed");
        case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
                return error("waitpid is confused");
        case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
-               return error("%s died of signal", update_hook);
+               return error("%s died of signal", hook_name);
        case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
-               return error("%s died strangely", update_hook);
+               return error("%s died strangely", hook_name);
        default:
-               error("%s exited with error code %d", update_hook, -code);
+               error("%s exited with error code %d", hook_name, -code);
                return -code;
        }
 }
 
-static int update(struct command *cmd)
+static int run_hook(const char *hook_name)
 {
-       const char *name = cmd->ref_name;
-       unsigned char *old_sha1 = cmd->old_sha1;
-       unsigned char *new_sha1 = cmd->new_sha1;
-       char new_hex[60], *old_hex, *lock_name;
-       int newfd, namelen, written;
-
-       cmd->error_string = NULL;
-       if (!strncmp(name, "refs/", 5) && check_ref_format(name + 5)) {
-               cmd->error_string = "funny refname";
-               return error("refusing to create funny ref '%s' locally",
-                            name);
+       static char buf[sizeof(commands->old_sha1) * 2 + PATH_MAX + 4];
+       struct command *cmd;
+       struct child_process proc;
+       const char *argv[2];
+       int have_input = 0, code;
+
+       for (cmd = commands; !have_input && cmd; cmd = cmd->next) {
+               if (!cmd->error_string)
+                       have_input = 1;
        }
 
-       namelen = strlen(name);
-       lock_name = xmalloc(namelen + 10);
-       memcpy(lock_name, name, namelen);
-       memcpy(lock_name + namelen, ".lock", 6);
-
-       strcpy(new_hex, sha1_to_hex(new_sha1));
-       old_hex = sha1_to_hex(old_sha1);
-       if (!has_sha1_file(new_sha1)) {
-               cmd->error_string = "bad pack";
-               return error("unpack should have generated %s, "
-                            "but I can't find it!", new_hex);
+       if (!have_input || access(hook_name, X_OK) < 0)
+               return 0;
+
+       argv[0] = hook_name;
+       argv[1] = NULL;
+
+       memset(&proc, 0, sizeof(proc));
+       proc.argv = argv;
+       proc.in = -1;
+       proc.stdout_to_stderr = 1;
+
+       code = start_command(&proc);
+       if (code)
+               return hook_status(code, hook_name);
+       for (cmd = commands; cmd; cmd = cmd->next) {
+               if (!cmd->error_string) {
+                       size_t n = snprintf(buf, sizeof(buf), "%s %s %s\n",
+                               sha1_to_hex(cmd->old_sha1),
+                               sha1_to_hex(cmd->new_sha1),
+                               cmd->ref_name);
+                       if (write_in_full(proc.in, buf, n) != n)
+                               break;
+               }
        }
-       safe_create_leading_directories(lock_name);
+       return hook_status(finish_command(&proc), hook_name);
+}
+
+static int run_update_hook(struct command *cmd)
+{
+       static const char update_hook[] = "hooks/update";
+       struct child_process proc;
+       const char *argv[5];
+
+       if (access(update_hook, X_OK) < 0)
+               return 0;
+
+       argv[0] = update_hook;
+       argv[1] = cmd->ref_name;
+       argv[2] = sha1_to_hex(cmd->old_sha1);
+       argv[3] = sha1_to_hex(cmd->new_sha1);
+       argv[4] = NULL;
+
+       memset(&proc, 0, sizeof(proc));
+       proc.argv = argv;
+       proc.no_stdin = 1;
+       proc.stdout_to_stderr = 1;
+
+       return hook_status(run_command(&proc), update_hook);
+}
+
+static const char *update(struct command *cmd)
+{
+       const char *name = cmd->ref_name;
+       unsigned char *old_sha1 = cmd->old_sha1;
+       unsigned char *new_sha1 = cmd->new_sha1;
+       struct ref_lock *lock;
 
-       newfd = open(lock_name, O_CREAT | O_EXCL | O_WRONLY, 0666);
-       if (newfd < 0) {
-               cmd->error_string = "can't lock";
-               return error("unable to create %s (%s)",
-                            lock_name, strerror(errno));
+       if (!prefixcmp(name, "refs/") && check_ref_format(name + 5)) {
+               error("refusing to create funny ref '%s' locally", name);
+               return "funny refname";
        }
 
-       /* Write the ref with an ending '\n' */
-       new_hex[40] = '\n';
-       new_hex[41] = 0;
-       written = write(newfd, new_hex, 41);
-       /* Remove the '\n' again */
-       new_hex[40] = 0;
-
-       close(newfd);
-       if (written != 41) {
-               unlink(lock_name);
-               cmd->error_string = "can't write";
-               return error("unable to write %s", lock_name);
+       if (!is_null_sha1(new_sha1) && !has_sha1_file(new_sha1)) {
+               error("unpack should have generated %s, "
+                     "but I can't find it!", sha1_to_hex(new_sha1));
+               return "bad pack";
        }
-       if (verify_old_ref(name, old_hex) < 0) {
-               unlink(lock_name);
-               cmd->error_string = "raced";
-               return error("%s changed during push", name);
+       if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
+           !is_null_sha1(old_sha1) &&
+           !prefixcmp(name, "refs/heads/")) {
+               struct commit *old_commit, *new_commit;
+               struct commit_list *bases, *ent;
+
+               old_commit = (struct commit *)parse_object(old_sha1);
+               new_commit = (struct commit *)parse_object(new_sha1);
+               bases = get_merge_bases(old_commit, new_commit, 1);
+               for (ent = bases; ent; ent = ent->next)
+                       if (!hashcmp(old_sha1, ent->item->object.sha1))
+                               break;
+               free_commit_list(bases);
+               if (!ent) {
+                       error("denying non-fast forward %s"
+                             " (you should pull first)", name);
+                       return "non-fast forward";
+               }
        }
-       if (run_update_hook(name, old_hex, new_hex)) {
-               unlink(lock_name);
-               cmd->error_string = "hook declined";
-               return error("hook declined to update %s", name);
+       if (run_update_hook(cmd)) {
+               error("hook declined to update %s", name);
+               return "hook declined";
        }
-       else if (rename(lock_name, name) < 0) {
-               unlink(lock_name);
-               cmd->error_string = "can't rename";
-               return error("unable to replace %s", name);
+
+       if (is_null_sha1(new_sha1)) {
+               if (delete_ref(name, old_sha1)) {
+                       error("failed to delete %s", name);
+                       return "failed to delete";
+               }
+               fprintf(stderr, "%s: %s -> deleted\n", name,
+                       sha1_to_hex(old_sha1));
+               return NULL; /* good */
        }
        else {
-               fprintf(stderr, "%s: %s -> %s\n", name, old_hex, new_hex);
-               return 0;
+               lock = lock_any_ref_for_update(name, old_sha1);
+               if (!lock) {
+                       error("failed to lock %s", name);
+                       return "failed to lock";
+               }
+               if (write_ref_sha1(lock, new_sha1, "push")) {
+                       return "failed to write"; /* error() already called */
+               }
+               fprintf(stderr, "%s: %s -> %s\n", name,
+                       sha1_to_hex(old_sha1), sha1_to_hex(new_sha1));
+               return NULL; /* good */
        }
 }
 
@@ -178,14 +231,14 @@ static void run_update_post_hook(struct command *cmd)
        int argc;
        const char **argv;
 
-       if (access(update_post_hook, X_OK) < 0)
-               return;
-       for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
+       for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
                if (cmd_p->error_string)
                        continue;
                argc++;
        }
-       argv = xmalloc(sizeof(*argv) * (1 + argc));
+       if (!argc || access(update_post_hook, X_OK) < 0)
+               return;
+       argv = xmalloc(sizeof(*argv) * (2 + argc));
        argv[0] = update_post_hook;
 
        for (argc = 1, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
@@ -198,22 +251,34 @@ static void run_update_post_hook(struct command *cmd)
                argc++;
        }
        argv[argc] = NULL;
-       run_command_v_opt(argc, argv, RUN_COMMAND_NO_STDIO);
+       run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
+               | RUN_COMMAND_STDOUT_TO_STDERR);
 }
 
-/*
- * This gets called after(if) we've successfully
- * unpacked the data payload.
- */
-static void execute_commands(void)
+static void execute_commands(const char *unpacker_error)
 {
        struct command *cmd = commands;
 
+       if (unpacker_error) {
+               while (cmd) {
+                       cmd->error_string = "n/a (unpacker error)";
+                       cmd = cmd->next;
+               }
+               return;
+       }
+
+       if (run_hook(pre_receive_hook)) {
+               while (cmd) {
+                       cmd->error_string = "pre-receive hook declined";
+                       cmd = cmd->next;
+               }
+               return;
+       }
+
        while (cmd) {
-               update(cmd);
+               cmd->error_string = update(cmd);
                cmd = cmd->next;
        }
-       run_update_post_hook(commands);
 }
 
 static void read_head_info(void)
@@ -249,36 +314,121 @@ static void read_head_info(void)
                hashcpy(cmd->old_sha1, old_sha1);
                hashcpy(cmd->new_sha1, new_sha1);
                memcpy(cmd->ref_name, line + 82, len - 81);
-               cmd->error_string = "n/a (unpacker error)";
+               cmd->error_string = NULL;
                cmd->next = NULL;
                *p = cmd;
                p = &cmd->next;
        }
 }
 
-static const char *unpack(int *error_code)
+static const char *parse_pack_header(struct pack_header *hdr)
 {
-       int code = run_command_v_opt(1, unpacker, RUN_GIT_CMD);
+       switch (read_pack_header(0, hdr)) {
+       case PH_ERROR_EOF:
+               return "eof before pack header was fully read";
+
+       case PH_ERROR_PACK_SIGNATURE:
+               return "protocol error (pack signature mismatch detected)";
+
+       case PH_ERROR_PROTOCOL:
+               return "protocol error (pack version unsupported)";
+
+       default:
+               return "unknown error in parse_pack_header";
 
-       *error_code = 0;
-       switch (code) {
        case 0:
                return NULL;
-       case -ERR_RUN_COMMAND_FORK:
-               return "unpack fork failed";
-       case -ERR_RUN_COMMAND_EXEC:
-               return "unpack execute failed";
-       case -ERR_RUN_COMMAND_WAITPID:
-               return "waitpid failed";
-       case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
-               return "waitpid is confused";
-       case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
-               return "unpacker died of signal";
-       case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
-               return "unpacker died strangely";
-       default:
-               *error_code = -code;
-               return "unpacker exited with error code";
+       }
+}
+
+static const char *pack_lockfile;
+
+static const char *unpack(void)
+{
+       struct pack_header hdr;
+       const char *hdr_err;
+       char hdr_arg[38];
+
+       hdr_err = parse_pack_header(&hdr);
+       if (hdr_err)
+               return hdr_err;
+       snprintf(hdr_arg, sizeof(hdr_arg), "--pack_header=%u,%u",
+                       ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
+
+       if (ntohl(hdr.hdr_entries) < unpack_limit) {
+               int code;
+               const char *unpacker[3];
+               unpacker[0] = "unpack-objects";
+               unpacker[1] = hdr_arg;
+               unpacker[2] = NULL;
+               code = run_command_v_opt(unpacker, RUN_GIT_CMD);
+               switch (code) {
+               case 0:
+                       return NULL;
+               case -ERR_RUN_COMMAND_FORK:
+                       return "unpack fork failed";
+               case -ERR_RUN_COMMAND_EXEC:
+                       return "unpack execute failed";
+               case -ERR_RUN_COMMAND_WAITPID:
+                       return "waitpid failed";
+               case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
+                       return "waitpid is confused";
+               case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
+                       return "unpacker died of signal";
+               case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
+                       return "unpacker died strangely";
+               default:
+                       return "unpacker exited with error code";
+               }
+       } else {
+               const char *keeper[6];
+               int s, len, status;
+               char keep_arg[256];
+               char packname[46];
+               struct child_process ip;
+
+               s = sprintf(keep_arg, "--keep=receive-pack %i on ", getpid());
+               if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
+                       strcpy(keep_arg + s, "localhost");
+
+               keeper[0] = "index-pack";
+               keeper[1] = "--stdin";
+               keeper[2] = "--fix-thin";
+               keeper[3] = hdr_arg;
+               keeper[4] = keep_arg;
+               keeper[5] = NULL;
+               memset(&ip, 0, sizeof(ip));
+               ip.argv = keeper;
+               ip.out = -1;
+               ip.git_cmd = 1;
+               if (start_command(&ip))
+                       return "index-pack fork failed";
+
+               /*
+                * The first thing we expects from index-pack's output
+                * is "pack\t%40s\n" or "keep\t%40s\n" (46 bytes) where
+                * %40s is the newly created pack SHA1 name.  In the "keep"
+                * case, we need it to remove the corresponding .keep file
+                * later on.  If we don't get that then tough luck with it.
+                */
+               for (len = 0;
+                    len < 46 && (s = xread(ip.out, packname+len, 46-len)) > 0;
+                    len += s);
+               if (len == 46 && packname[45] == '\n' &&
+                   memcmp(packname, "keep\t", 5) == 0) {
+                       char path[PATH_MAX];
+                       packname[45] = 0;
+                       snprintf(path, sizeof(path), "%s/pack/pack-%s.keep",
+                                get_object_directory(), packname + 5);
+                       pack_lockfile = xstrdup(path);
+               }
+
+               status = finish_command(&ip);
+               if (!status) {
+                       reprepare_packed_git();
+                       return NULL;
+               }
+               return "index-pack abnormal exit";
        }
 }
 
@@ -298,6 +448,16 @@ static void report(const char *unpack_status)
        packet_flush(1);
 }
 
+static int delete_only(struct command *cmd)
+{
+       while (cmd) {
+               if (!is_null_sha1(cmd->new_sha1))
+                       return 0;
+               cmd = cmd->next;
+       }
+       return 1;
+}
+
 int main(int argc, char **argv)
 {
        int i;
@@ -318,9 +478,19 @@ int main(int argc, char **argv)
        if (!dir)
                usage(receive_pack_usage);
 
-       if(!enter_repo(dir, 0))
+       if (!enter_repo(dir, 0))
                die("'%s': unable to chdir or not a git archive", dir);
 
+       if (is_repository_shallow())
+               die("attempt to push into a shallow repository");
+
+       git_config(receive_pack_config);
+
+       if (0 <= transfer_unpack_limit)
+               unpack_limit = transfer_unpack_limit;
+       else if (0 <= receive_unpack_limit)
+               unpack_limit = receive_unpack_limit;
+
        write_head_info();
 
        /* EOF */
@@ -328,12 +498,17 @@ int main(int argc, char **argv)
 
        read_head_info();
        if (commands) {
-               int code;
-               const char *unpack_status = unpack(&code);
-               if (!unpack_status)
-                       execute_commands();
+               const char *unpack_status = NULL;
+
+               if (!delete_only(commands))
+                       unpack_status = unpack();
+               execute_commands(unpack_status);
+               if (pack_lockfile)
+                       unlink(pack_lockfile);
                if (report_status)
                        report(unpack_status);
+               run_hook(post_receive_hook);
+               run_update_post_hook(commands);
        }
        return 0;
 }