Merge branch 'mv/maint-branch-m-symref'

* mv/maint-branch-m-symref:
  update-ref --no-deref -d: handle the case when the pointed ref is packed
  git branch -m: forbid renaming of a symref
  Fix git update-ref --no-deref -d.
  rename_ref(): handle the case when the reflog of a ref does not exist
  Fix git branch -m for symrefs.

diff --cc builtin-branch.c
Simple merge

diff --cc builtin-receive-pack.c
index 2c0225c89a44a28150806608ea3956c44e27ef6f,0000000000000000000000000000000000000000..7f9f134806766244bf1eb3de2de3a823a62b180a
mode 100644,000000..100644
--- 1/builtin-receive-pack.c
--- /dev/null
+++ b/builtin-receive-pack.c
@@@ -1,575 -1,0 +1,575 @@@
-               if (delete_ref(name, old_sha1)) {
 +#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"
 +#include "remote.h"
 +#include "transport.h"
 +
 +static const char receive_pack_usage[] = "git-receive-pack <git-dir>";
 +
 +static int deny_deletes = 0;
 +static int deny_non_fast_forwards = 0;
 +static int receive_fsck_objects;
 +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 delete-refs ";
 +static int capabilities_sent;
 +
 +static int receive_pack_config(const char *var, const char *value, void *cb)
 +{
 +      if (strcmp(var, "receive.denydeletes") == 0) {
 +              deny_deletes = git_config_bool(var, value);
 +              return 0;
 +      }
 +
 +      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;
 +      }
 +
 +      if (strcmp(var, "receive.fsckobjects") == 0) {
 +              receive_fsck_objects = git_config_bool(var, value);
 +              return 0;
 +      }
 +
 +      return git_default_config(var, value, cb);
 +}
 +
 +static int show_ref(const char *path, const unsigned char *sha1, int flag, void *cb_data)
 +{
 +      if (capabilities_sent)
 +              packet_write(1, "%s %s\n", sha1_to_hex(sha1), path);
 +      else
 +              packet_write(1, "%s %s%c%s\n",
 +                           sha1_to_hex(sha1), path, 0, capabilities);
 +      capabilities_sent = 1;
 +      return 0;
 +}
 +
 +static void write_head_info(void)
 +{
 +      for_each_ref(show_ref, NULL);
 +      if (!capabilities_sent)
 +              show_ref("capabilities^{}", null_sha1, 0, NULL);
 +
 +}
 +
 +struct command {
 +      struct command *next;
 +      const char *error_string;
 +      unsigned char old_sha1[20];
 +      unsigned char new_sha1[20];
 +      char ref_name[FLEX_ARRAY]; /* more */
 +};
 +
 +static struct command *commands;
 +
 +static const char pre_receive_hook[] = "hooks/pre-receive";
 +static const char post_receive_hook[] = "hooks/post-receive";
 +
 +static int hook_status(int code, const char *hook_name)
 +{
 +      switch (code) {
 +      case 0:
 +              return 0;
 +      case -ERR_RUN_COMMAND_FORK:
 +              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", hook_name);
 +      case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
 +              return error("%s died strangely", hook_name);
 +      default:
 +              error("%s exited with error code %d", hook_name, -code);
 +              return -code;
 +      }
 +}
 +
 +static int run_hook(const char *hook_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;
 +      }
 +
 +      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;
 +              }
 +      }
 +      close(proc.in);
 +      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;
 +
 +      /* only refs/... are allowed */
 +      if (prefixcmp(name, "refs/") || check_ref_format(name + 5)) {
 +              error("refusing to create funny ref '%s' remotely", name);
 +              return "funny refname";
 +      }
 +
 +      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 (deny_deletes && is_null_sha1(new_sha1) &&
 +          !is_null_sha1(old_sha1) &&
 +          !prefixcmp(name, "refs/heads/")) {
 +              error("denying ref deletion for %s", name);
 +              return "deletion prohibited";
 +      }
 +      if (deny_non_fast_forwards && !is_null_sha1(new_sha1) &&
 +          !is_null_sha1(old_sha1) &&
 +          !prefixcmp(name, "refs/heads/")) {
 +              struct object *old_object, *new_object;
 +              struct commit *old_commit, *new_commit;
 +              struct commit_list *bases, *ent;
 +
 +              old_object = parse_object(old_sha1);
 +              new_object = parse_object(new_sha1);
 +
 +              if (!old_object || !new_object ||
 +                  old_object->type != OBJ_COMMIT ||
 +                  new_object->type != OBJ_COMMIT) {
 +                      error("bad sha1 objects for %s", name);
 +                      return "bad ref";
 +              }
 +              old_commit = (struct commit *)old_object;
 +              new_commit = (struct commit *)new_object;
 +              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(cmd)) {
 +              error("hook declined to update %s", name);
 +              return "hook declined";
 +      }
 +
 +      if (is_null_sha1(new_sha1)) {
 +              if (!parse_object(old_sha1)) {
 +                      warning ("Allowing deletion of corrupt ref.");
 +                      old_sha1 = NULL;
 +              }
++              if (delete_ref(name, old_sha1, 0)) {
 +                      error("failed to delete %s", name);
 +                      return "failed to delete";
 +              }
 +              return NULL; /* good */
 +      }
 +      else {
 +              lock = lock_any_ref_for_update(name, old_sha1, 0);
 +              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 */
 +              }
 +              return NULL; /* good */
 +      }
 +}
 +
 +static char update_post_hook[] = "hooks/post-update";
 +
 +static void run_update_post_hook(struct command *cmd)
 +{
 +      struct command *cmd_p;
 +      int argc;
 +      const char **argv;
 +
 +      for (argc = 0, cmd_p = cmd; cmd_p; cmd_p = cmd_p->next) {
 +              if (cmd_p->error_string)
 +                      continue;
 +              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) {
 +              char *p;
 +              if (cmd_p->error_string)
 +                      continue;
 +              p = xmalloc(strlen(cmd_p->ref_name) + 1);
 +              strcpy(p, cmd_p->ref_name);
 +              argv[argc] = p;
 +              argc++;
 +      }
 +      argv[argc] = NULL;
 +      run_command_v_opt(argv, RUN_COMMAND_NO_STDIN
 +              | RUN_COMMAND_STDOUT_TO_STDERR);
 +}
 +
 +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) {
 +              cmd->error_string = update(cmd);
 +              cmd = cmd->next;
 +      }
 +}
 +
 +static void read_head_info(void)
 +{
 +      struct command **p = &commands;
 +      for (;;) {
 +              static char line[1000];
 +              unsigned char old_sha1[20], new_sha1[20];
 +              struct command *cmd;
 +              char *refname;
 +              int len, reflen;
 +
 +              len = packet_read_line(0, line, sizeof(line));
 +              if (!len)
 +                      break;
 +              if (line[len-1] == '\n')
 +                      line[--len] = 0;
 +              if (len < 83 ||
 +                  line[40] != ' ' ||
 +                  line[81] != ' ' ||
 +                  get_sha1_hex(line, old_sha1) ||
 +                  get_sha1_hex(line + 41, new_sha1))
 +                      die("protocol error: expected old/new/ref, got '%s'",
 +                          line);
 +
 +              refname = line + 82;
 +              reflen = strlen(refname);
 +              if (reflen + 82 < len) {
 +                      if (strstr(refname + reflen + 1, "report-status"))
 +                              report_status = 1;
 +              }
 +              cmd = xmalloc(sizeof(struct command) + len - 80);
 +              hashcpy(cmd->old_sha1, old_sha1);
 +              hashcpy(cmd->new_sha1, new_sha1);
 +              memcpy(cmd->ref_name, line + 82, len - 81);
 +              cmd->error_string = NULL;
 +              cmd->next = NULL;
 +              *p = cmd;
 +              p = &cmd->next;
 +      }
 +}
 +
 +static const char *parse_pack_header(struct pack_header *hdr)
 +{
 +      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";
 +
 +      case 0:
 +              return NULL;
 +      }
 +}
 +
 +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=%"PRIu32",%"PRIu32,
 +                      ntohl(hdr.hdr_version), ntohl(hdr.hdr_entries));
 +
 +      if (ntohl(hdr.hdr_entries) < unpack_limit) {
 +              int code, i = 0;
 +              const char *unpacker[4];
 +              unpacker[i++] = "unpack-objects";
 +              if (receive_fsck_objects)
 +                      unpacker[i++] = "--strict";
 +              unpacker[i++] = hdr_arg;
 +              unpacker[i++] = 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[7];
 +              int s, status, i = 0;
 +              char keep_arg[256];
 +              struct child_process ip;
 +
 +              s = sprintf(keep_arg, "--keep=receive-pack %"PRIuMAX" on ", (uintmax_t) getpid());
 +              if (gethostname(keep_arg + s, sizeof(keep_arg) - s))
 +                      strcpy(keep_arg + s, "localhost");
 +
 +              keeper[i++] = "index-pack";
 +              keeper[i++] = "--stdin";
 +              if (receive_fsck_objects)
 +                      keeper[i++] = "--strict";
 +              keeper[i++] = "--fix-thin";
 +              keeper[i++] = hdr_arg;
 +              keeper[i++] = keep_arg;
 +              keeper[i++] = 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";
 +              pack_lockfile = index_pack_lockfile(ip.out);
 +              close(ip.out);
 +              status = finish_command(&ip);
 +              if (!status) {
 +                      reprepare_packed_git();
 +                      return NULL;
 +              }
 +              return "index-pack abnormal exit";
 +      }
 +}
 +
 +static void report(const char *unpack_status)
 +{
 +      struct command *cmd;
 +      packet_write(1, "unpack %s\n",
 +                   unpack_status ? unpack_status : "ok");
 +      for (cmd = commands; cmd; cmd = cmd->next) {
 +              if (!cmd->error_string)
 +                      packet_write(1, "ok %s\n",
 +                                   cmd->ref_name);
 +              else
 +                      packet_write(1, "ng %s %s\n",
 +                                   cmd->ref_name, cmd->error_string);
 +      }
 +      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;
 +}
 +
 +static int add_refs_from_alternate(struct alternate_object_database *e, void *unused)
 +{
 +      char *other;
 +      size_t len;
 +      struct remote *remote;
 +      struct transport *transport;
 +      const struct ref *extra;
 +
 +      e->name[-1] = '\0';
 +      other = xstrdup(make_absolute_path(e->base));
 +      e->name[-1] = '/';
 +      len = strlen(other);
 +
 +      while (other[len-1] == '/')
 +              other[--len] = '\0';
 +      if (len < 8 || memcmp(other + len - 8, "/objects", 8))
 +              return 0;
 +      /* Is this a git repository with refs? */
 +      memcpy(other + len - 8, "/refs", 6);
 +      if (!is_directory(other))
 +              return 0;
 +      other[len - 8] = '\0';
 +      remote = remote_get(other);
 +      transport = transport_get(remote, other);
 +      for (extra = transport_get_remote_refs(transport);
 +           extra;
 +           extra = extra->next) {
 +              add_extra_ref(".have", extra->old_sha1, 0);
 +      }
 +      transport_disconnect(transport);
 +      free(other);
 +      return 0;
 +}
 +
 +static void add_alternate_refs(void)
 +{
 +      foreach_alt_odb(add_refs_from_alternate, NULL);
 +}
 +
 +int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 +{
 +      int i;
 +      char *dir = NULL;
 +
 +      argv++;
 +      for (i = 1; i < argc; i++) {
 +              const char *arg = *argv++;
 +
 +              if (*arg == '-') {
 +                      /* Do flag handling here */
 +                      usage(receive_pack_usage);
 +              }
 +              if (dir)
 +                      usage(receive_pack_usage);
 +              dir = xstrdup(arg);
 +      }
 +      if (!dir)
 +              usage(receive_pack_usage);
 +
 +      setup_path();
 +
 +      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, NULL);
 +
 +      if (0 <= transfer_unpack_limit)
 +              unpack_limit = transfer_unpack_limit;
 +      else if (0 <= receive_unpack_limit)
 +              unpack_limit = receive_unpack_limit;
 +
 +      add_alternate_refs();
 +      write_head_info();
 +      clear_extra_refs();
 +
 +      /* EOF */
 +      packet_flush(1);
 +
 +      read_head_info();
 +      if (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;
 +}

diff --cc builtin-remote.c
Simple merge

diff --cc builtin-send-pack.c
Simple merge

diff --cc builtin-tag.c
Simple merge

diff --cc cache.h
Simple merge

diff --cc refs.c
Simple merge