#include "builtin.h"

#include "config.h"

#include "environment.h"

#include "exec-cmd.h"

#include "gettext.h"

#include "help.h"

#include "pager.h"

#include "read-cache-ll.h"

#include "run-command.h"

#include "alias.h"

#include "replace-object.h"

#include "setup.h"

#include "attr.h"

#include "shallow.h"

#include "trace.h"

#include "trace2.h"

#define RUN_SETUP   (1<<0)

#define RUN_SETUP_GENTLY  (1<<1)

#define USE_PAGER   (1<<2)

/*

 * require working tree to be present -- anything uses this needs

 * RUN_SETUP for reading from the configuration file.

 */

#define NEED_WORK_TREE    (1<<3)

#define DELAY_PAGER_CONFIG  (1<<4)

#define NO_PARSEOPT   (1<<5) /* parse-options is not used */

struct cmd_struct {

  const char *cmd;

  int (*fn)(int, const char **, const char *);

  unsigned int option;

};

const char git_usage_string[] =

  N_("git [-v | --version] [-h | --help] [-C <path>] [-c <name>=<value>]\n"

     "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"

     "           [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--bare]\n"

     "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"

     "           [--config-env=<name>=<envvar>] <command> [<args>]");

const char git_more_info_string[] =

  N_("'git help -a' and 'git help -g' list available subcommands and some\n"

     "concept guides. See 'git help <command>' or 'git help <concept>'\n"

     "to read about a specific subcommand or concept.\n"

     "See 'git help git' for an overview of the system.");

static int use_pager = -1;

static void list_builtins(struct string_list *list, unsigned int exclude_option);

static void exclude_helpers_from_list(struct string_list *list)

{

  int i = 0;

  while (i < list->nr) {

    if (strstr(list->items[i].string, "--"))

      unsorted_string_list_delete_item(list, i, 0);

    else

      i++;

  }

}

static int match_token(const char *spec, int len, const char *token)

{

  int token_len = strlen(token);

  return len == token_len && !strncmp(spec, token, token_len);

}

static int list_cmds(const char *spec)

{

  struct string_list list = STRING_LIST_INIT_DUP;

  int i;

  int nongit;

  /*

  * Set up the repository so we can pick up any repo-level config (like

  * completion.commands).

  */

  setup_git_directory_gently(&nongit);

  while (*spec) {

    const char *sep = strchrnul(spec, ',');

    int len = sep - spec;

    if (match_token(spec, len, "builtins"))

      list_builtins(&list, 0);

    else if (match_token(spec, len, "main"))

      list_all_main_cmds(&list);

    else if (match_token(spec, len, "others"))

      list_all_other_cmds(&list);

    else if (match_token(spec, len, "nohelpers"))

      exclude_helpers_from_list(&list);

    else if (match_token(spec, len, "alias"))

      list_aliases(&list);

    else if (match_token(spec, len, "config"))

      list_cmds_by_config(&list);

    else if (len > 5 && !strncmp(spec, "list-", 5)) {

      struct strbuf sb = STRBUF_INIT;

      strbuf_add(&sb, spec + 5, len - 5);

      list_cmds_by_category(&list, sb.buf);

      strbuf_release(&sb);

    }

    else

      die(_("unsupported command listing type '%s'"), spec);

    spec += len;

    if (*spec == ',')

      spec++;

  }

  for (i = 0; i < list.nr; i++)

    puts(list.items[i].string);

  string_list_clear(&list, 0);

  return 0;

}

static void commit_pager_choice(void)

{

  switch (use_pager) {

  case 0:

    setenv("GIT_PAGER", "cat", 1);

    break;

  case 1:

    setup_pager();

    break;

  default:

    break;

  }

}

void setup_auto_pager(const char *cmd, int def)

{

  if (use_pager != -1 || pager_in_use())

    return;

  use_pager = check_pager_config(cmd);

  if (use_pager == -1)

    use_pager = def;

  commit_pager_choice();

}

static int handle_options(const char ***argv, int *argc, int *envchanged)

{

  const char **orig_argv = *argv;

  while (*argc > 0) {

    const char *cmd = (*argv)[0];

    if (cmd[0] != '-')

      break;

    /*

     * For legacy reasons, the "version" and "help"

     * commands can be written with "--" prepended

     * to make them look like flags.

     */

    if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h") ||

        !strcmp(cmd, "--version") || !strcmp(cmd, "-v"))

      break;

    /*

     * Check remaining flags.

     */

    if (skip_prefix(cmd, "--exec-path", &cmd)) {

      if (*cmd == '=')

        git_set_exec_path(cmd + 1);

      else {

        puts(git_exec_path());

        trace2_cmd_name("_query_");

        exit(0);

      }

    } else if (!strcmp(cmd, "--html-path")) {

      puts(system_path(GIT_HTML_PATH));

      trace2_cmd_name("_query_");

      exit(0);

    } else if (!strcmp(cmd, "--man-path")) {

      puts(system_path(GIT_MAN_PATH));

      trace2_cmd_name("_query_");

      exit(0);

    } else if (!strcmp(cmd, "--info-path")) {

      puts(system_path(GIT_INFO_PATH));

      trace2_cmd_name("_query_");

      exit(0);

    } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {

      use_pager = 1;

    } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {

      use_pager = 0;

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--no-replace-objects")) {

      disable_replace_refs();

      setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--git-dir")) {

      if (*argc < 2) {

        fprintf(stderr, _("no directory given for '%s' option\n" ), "--git-dir");

        usage(git_usage_string);

      }

      setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);

      if (envchanged)

        *envchanged = 1;

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {

      setenv(GIT_DIR_ENVIRONMENT, cmd, 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--namespace")) {

      if (*argc < 2) {

        fprintf(stderr, _("no namespace given for --namespace\n" ));

        usage(git_usage_string);

      }

      setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);

      if (envchanged)

        *envchanged = 1;

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--namespace=", &cmd)) {

      setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--work-tree")) {

      if (*argc < 2) {

        fprintf(stderr, _("no directory given for '%s' option\n" ), "--work-tree");

        usage(git_usage_string);

      }

      setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);

      if (envchanged)

        *envchanged = 1;

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {

      setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--bare")) {

      char *cwd = xgetcwd();

      is_bare_repository_cfg = 1;

      setenv(GIT_DIR_ENVIRONMENT, cwd, 0);

      free(cwd);

      setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "-c")) {

      if (*argc < 2) {

        fprintf(stderr, _("-c expects a configuration string\n" ));

        usage(git_usage_string);

      }

      git_config_push_parameter((*argv)[1]);

      (*argv)++;

      (*argc)--;

    } else if (!strcmp(cmd, "--config-env")) {

      if (*argc < 2) {

        fprintf(stderr, _("no config key given for --config-env\n" ));

        usage(git_usage_string);

      }

      git_config_push_env((*argv)[1]);

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--config-env=", &cmd)) {

      git_config_push_env(cmd);

    } else if (!strcmp(cmd, "--literal-pathspecs")) {

      setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--no-literal-pathspecs")) {

      setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--glob-pathspecs")) {

      setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--noglob-pathspecs")) {

      setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--icase-pathspecs")) {

      setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--no-optional-locks")) {

      setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "--shallow-file")) {

      (*argv)++;

      (*argc)--;

      set_alternate_shallow_file(the_repository, (*argv)[0], 1);

      if (envchanged)

        *envchanged = 1;

    } else if (!strcmp(cmd, "-C")) {

      if (*argc < 2) {

        fprintf(stderr, _("no directory given for '%s' option\n" ), "-C");

        usage(git_usage_string);

      }

      if ((*argv)[1][0]) {

        if (chdir((*argv)[1]))

          die_errno("cannot change to '%s'", (*argv)[1]);

        if (envchanged)

          *envchanged = 1;

      }

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {

      trace2_cmd_name("_query_");

      if (!strcmp(cmd, "parseopt")) {

        struct string_list list = STRING_LIST_INIT_DUP;

        int i;

        list_builtins(&list, NO_PARSEOPT);

        for (i = 0; i < list.nr; i++)

          printf("%s ", list.items[i].string);

        string_list_clear(&list, 0);

        exit(0);

      } else {

        exit(list_cmds(cmd));

      }

    } else if (!strcmp(cmd, "--attr-source")) {

      if (*argc < 2) {

        fprintf(stderr, _("no attribute source given for --attr-source\n" ));

        usage(git_usage_string);

      }

      setenv(GIT_ATTR_SOURCE_ENVIRONMENT, (*argv)[1], 1);

      if (envchanged)

        *envchanged = 1;

      (*argv)++;

      (*argc)--;

    } else if (skip_prefix(cmd, "--attr-source=", &cmd)) {

      set_git_attr_source(cmd);

      setenv(GIT_ATTR_SOURCE_ENVIRONMENT, cmd, 1);

      if (envchanged)

        *envchanged = 1;

    } else {

      fprintf(stderr, _("unknown option: %s\n"), cmd);

      usage(git_usage_string);

    }

    (*argv)++;

    (*argc)--;

  }

  return (*argv) - orig_argv;

}

static int handle_alias(int *argcp, const char ***argv)

{

  int envchanged = 0, ret = 0, saved_errno = errno;

  int count, option_count;

  const char **new_argv;

  const char *alias_command;

  char *alias_string;

  alias_command = (*argv)[0];

  alias_string = alias_lookup(alias_command);

  if (alias_string) {

    if (*argcp > 1 && !strcmp((*argv)[1], "-h"))

      fprintf_ln(stderr, _("'%s' is aliased to '%s'"),

           alias_command, alias_string);

    if (alias_string[0] == '!') {

      struct child_process child = CHILD_PROCESS_INIT;

      int nongit_ok;

      /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */

      setup_git_directory_gently(&nongit_ok);

      commit_pager_choice();

      child.use_shell = 1;

      child.clean_on_exit = 1;

      child.wait_after_clean = 1;

      child.trace2_child_class = "shell_alias";

      strvec_push(&child.args, alias_string + 1);

      strvec_pushv(&child.args, (*argv) + 1);

      trace2_cmd_alias(alias_command, child.args.v);

      trace2_cmd_list_config();

      trace2_cmd_list_env_vars();

      trace2_cmd_name("_run_shell_alias_");

      ret = run_command(&child);

      if (ret >= 0)   /* normal exit */

        exit(ret);

      die_errno(_("while expanding alias '%s': '%s'"),

          alias_command, alias_string + 1);

    }

    count = split_cmdline(alias_string, &new_argv);

    if (count < 0)

      die(_("bad alias.%s string: %s"), alias_command,

          _(split_cmdline_strerror(count)));

    option_count = handle_options(&new_argv, &count, &envchanged);

    if (envchanged)

      die(_("alias '%s' changes environment variables.\n"

            "You can use '!git' in the alias to do this"),

          alias_command);

    MOVE_ARRAY(new_argv - option_count, new_argv, count);

    new_argv -= option_count;

    if (count < 1)

      die(_("empty alias for %s"), alias_command);

    if (!strcmp(alias_command, new_argv[0]))

      die(_("recursive alias: %s"), alias_command);

    trace_argv_printf(new_argv,

          "trace: alias expansion: %s =>",

          alias_command);

    REALLOC_ARRAY(new_argv, count + *argcp);

    /* insert after command name */

    COPY_ARRAY(new_argv + count, *argv + 1, *argcp);

    trace2_cmd_alias(alias_command, new_argv);

    trace2_cmd_list_config();

    trace2_cmd_list_env_vars();

    *argv = new_argv;

    *argcp += count - 1;

    ret = 1;

  }

  errno = saved_errno;

  return ret;

}

static int run_builtin(struct cmd_struct *p, int argc, const char **argv)

{

  int status, help;

  struct stat st;

  const char *prefix;

  int run_setup = (p->option & (RUN_SETUP | RUN_SETUP_GENTLY));

  help = argc == 2 && !strcmp(argv[1], "-h");

  if (help && (run_setup & RUN_SETUP))

    /* demote to GENTLY to allow 'git cmd -h' outside repo */

    run_setup = RUN_SETUP_GENTLY;

  if (run_setup & RUN_SETUP) {

    prefix = setup_git_directory();

  } else if (run_setup & RUN_SETUP_GENTLY) {

    int nongit_ok;

    prefix = setup_git_directory_gently(&nongit_ok);

  } else {

    prefix = NULL;

  }

  assert(!prefix || *prefix);

  precompose_argv_prefix(argc, argv, NULL);

  if (use_pager == -1 && run_setup &&

    !(p->option & DELAY_PAGER_CONFIG))

    use_pager = check_pager_config(p->cmd);

  if (use_pager == -1 && p->option & USE_PAGER)

    use_pager = 1;

  if (run_setup && startup_info->have_repository)

    /* get_git_dir() may set up repo, avoid that */

    trace_repo_setup();

  commit_pager_choice();

  if (!help && p->option & NEED_WORK_TREE)

    setup_work_tree();

  trace_argv_printf(argv, "trace: built-in: git");

  trace2_cmd_name(p->cmd);

  trace2_cmd_list_config();

  trace2_cmd_list_env_vars();

  validate_cache_entries(the_repository->index);

  status = p->fn(argc, argv, prefix);

  validate_cache_entries(the_repository->index);

  if (status)

    return status;

  /* Somebody closed stdout? */

  if (fstat(fileno(stdout), &st))

    return 0;

  /* Ignore write errors for pipes and sockets.. */

  if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))

    return 0;

  /* Check for ENOSPC and EIO errors.. */

  if (fflush(stdout))

    die_errno(_("write failure on standard output"));

  if (ferror(stdout))

    die(_("unknown write failure on standard output"));

  if (fclose(stdout))

    die_errno(_("close failed on standard output"));

  return 0;

}

static struct cmd_struct commands[] = {

  { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },

  { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },

  { "annotate", cmd_annotate, RUN_SETUP },

  { "apply", cmd_apply, RUN_SETUP_GENTLY },

  { "archive", cmd_archive, RUN_SETUP_GENTLY },

  { "bisect", cmd_bisect, RUN_SETUP },

  { "blame", cmd_blame, RUN_SETUP },

  { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },

  { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },

  { "bundle", cmd_bundle, RUN_SETUP_GENTLY },

  { "cat-file", cmd_cat_file, RUN_SETUP },

  { "check-attr", cmd_check_attr, RUN_SETUP },

  { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },

  { "check-mailmap", cmd_check_mailmap, RUN_SETUP },

  { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },

  { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },

  { "checkout--worker", cmd_checkout__worker,

    RUN_SETUP | NEED_WORK_TREE },

  { "checkout-index", cmd_checkout_index,

    RUN_SETUP | NEED_WORK_TREE},

  { "cherry", cmd_cherry, RUN_SETUP },

  { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },

  { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },

  { "clone", cmd_clone },

  { "column", cmd_column, RUN_SETUP_GENTLY },

  { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },

  { "commit-graph", cmd_commit_graph, RUN_SETUP },

  { "commit-tree", cmd_commit_tree, RUN_SETUP },

  { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },

  { "count-objects", cmd_count_objects, RUN_SETUP },

  { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },

  { "credential-cache", cmd_credential_cache },

  { "credential-cache--daemon", cmd_credential_cache_daemon },

  { "credential-store", cmd_credential_store },

  { "describe", cmd_describe, RUN_SETUP },

  { "diagnose", cmd_diagnose, RUN_SETUP_GENTLY },

  { "diff", cmd_diff, NO_PARSEOPT },

  { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },

  { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },

  { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },

  { "difftool", cmd_difftool, RUN_SETUP_GENTLY },

  { "fast-export", cmd_fast_export, RUN_SETUP },

  { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },

  { "fetch", cmd_fetch, RUN_SETUP },

  { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },

  { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },

  { "for-each-ref", cmd_for_each_ref, RUN_SETUP },

  { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },

  { "format-patch", cmd_format_patch, RUN_SETUP },

  { "fsck", cmd_fsck, RUN_SETUP },

  { "fsck-objects", cmd_fsck, RUN_SETUP },

  { "fsmonitor--daemon", cmd_fsmonitor__daemon, RUN_SETUP },

  { "gc", cmd_gc, RUN_SETUP },

  { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },

  { "grep", cmd_grep, RUN_SETUP_GENTLY },

  { "hash-object", cmd_hash_object },

  { "help", cmd_help },

  { "hook", cmd_hook, RUN_SETUP },

  { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },

  { "init", cmd_init_db },

  { "init-db", cmd_init_db },

  { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },

  { "log", cmd_log, RUN_SETUP },

  { "ls-files", cmd_ls_files, RUN_SETUP },

  { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },

  { "ls-tree", cmd_ls_tree, RUN_SETUP },

  { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },

  { "mailsplit", cmd_mailsplit, NO_PARSEOPT },

  { "maintenance", cmd_maintenance, RUN_SETUP },

  { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },

  { "merge-base", cmd_merge_base, RUN_SETUP },

  { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },

  { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },

  { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },

  { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },

  { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },

  { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },

  { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },

  { "merge-tree", cmd_merge_tree, RUN_SETUP },

  { "mktag", cmd_mktag, RUN_SETUP },

  { "mktree", cmd_mktree, RUN_SETUP },

  { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP },

  { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },

  { "name-rev", cmd_name_rev, RUN_SETUP },

  { "notes", cmd_notes, RUN_SETUP },

  { "pack-objects", cmd_pack_objects, RUN_SETUP },

  { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },

  { "pack-refs", cmd_pack_refs, RUN_SETUP },

  { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },

  { "pickaxe", cmd_blame, RUN_SETUP },

  { "prune", cmd_prune, RUN_SETUP },

  { "prune-packed", cmd_prune_packed, RUN_SETUP },

  { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },

  { "push", cmd_push, RUN_SETUP },

  { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },

  { "read-tree", cmd_read_tree, RUN_SETUP },

  { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },

  { "receive-pack", cmd_receive_pack },

  { "reflog", cmd_reflog, RUN_SETUP },

  { "remote", cmd_remote, RUN_SETUP },

  { "remote-ext", cmd_remote_ext, NO_PARSEOPT },

  { "remote-fd", cmd_remote_fd, NO_PARSEOPT },

  { "repack", cmd_repack, RUN_SETUP },

  { "replace", cmd_replace, RUN_SETUP },

  { "rerere", cmd_rerere, RUN_SETUP },

  { "reset", cmd_reset, RUN_SETUP },

  { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },

  { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },

  { "rev-parse", cmd_rev_parse, NO_PARSEOPT },

  { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },

  { "rm", cmd_rm, RUN_SETUP },

  { "send-pack", cmd_send_pack, RUN_SETUP },

  { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },

  { "show", cmd_show, RUN_SETUP },

  { "show-branch", cmd_show_branch, RUN_SETUP },

  { "show-index", cmd_show_index, RUN_SETUP_GENTLY },

  { "show-ref", cmd_show_ref, RUN_SETUP },

  { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP },

  { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },

  { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },

  { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },

  { "stripspace", cmd_stripspace },

  { "submodule--helper", cmd_submodule__helper, RUN_SETUP },

  { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },

  { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },

  { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },

  { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },

  { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },

  { "update-index", cmd_update_index, RUN_SETUP },

  { "update-ref", cmd_update_ref, RUN_SETUP },

  { "update-server-info", cmd_update_server_info, RUN_SETUP },

  { "upload-archive", cmd_upload_archive, NO_PARSEOPT },

  { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },

  { "upload-pack", cmd_upload_pack },

  { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },

  { "verify-commit", cmd_verify_commit, RUN_SETUP },

  { "verify-pack", cmd_verify_pack },

  { "verify-tag", cmd_verify_tag, RUN_SETUP },

  { "version", cmd_version },

  { "whatchanged", cmd_whatchanged, RUN_SETUP },

  { "worktree", cmd_worktree, RUN_SETUP },

  { "write-tree", cmd_write_tree, RUN_SETUP },

};

static struct cmd_struct *get_builtin(const char *s)

{

  int i;

  for (i = 0; i < ARRAY_SIZE(commands); i++) {

    struct cmd_struct *p = commands + i;

    if (!strcmp(s, p->cmd))

      return p;

  }

  return NULL;

}

int is_builtin(const char *s)

{

  return !!get_builtin(s);

}

static void list_builtins(struct string_list *out, unsigned int exclude_option)

{

  int i;

  for (i = 0; i < ARRAY_SIZE(commands); i++) {

    if (exclude_option &&

        (commands[i].option & exclude_option))

      continue;

    string_list_append(out, commands[i].cmd);

  }

}

void load_builtin_commands(const char *prefix, struct cmdnames *cmds)

{

  const char *name;

  int i;

  /*

   * Callers can ask for a subset of the commands based on a certain

   * prefix, which is then dropped from the added names. The names in

   * the `commands[]` array do not have the `git-` prefix, though,

   * therefore we must expect the `prefix` to at least start with `git-`.

   */

  if (!skip_prefix(prefix, "git-", &prefix))

    BUG("prefix '%s' must start with 'git-'", prefix);

  for (i = 0; i < ARRAY_SIZE(commands); i++)

    if (skip_prefix(commands[i].cmd, prefix, &name))

      add_cmdname(cmds, name, strlen(name));

}

#ifdef STRIP_EXTENSION

static void strip_extension(const char **argv)

{

  size_t len;

  if (strip_suffix(argv[0], STRIP_EXTENSION, &len))

    argv[0] = xmemdupz(argv[0], len);

}

#else

#define strip_extension(cmd)

#endif

static void handle_builtin(int argc, const char **argv)

{

  struct strvec args = STRVEC_INIT;

  const char *cmd;

  struct cmd_struct *builtin;

  strip_extension(argv);

  cmd = argv[0];

  /* Turn "git cmd --help" into "git help --exclude-guides cmd" */

  if (argc > 1 && !strcmp(argv[1], "--help")) {

    int i;

    argv[1] = argv[0];

    argv[0] = cmd = "help";

    for (i = 0; i < argc; i++) {

      strvec_push(&args, argv[i]);

      if (!i)

        strvec_push(&args, "--exclude-guides");

    }

    argc++;

    argv = args.v;

  }

  builtin = get_builtin(cmd);

  if (builtin)

    exit(run_builtin(builtin, argc, argv));

  strvec_clear(&args);

}

static void execv_dashed_external(const char **argv)

{

  struct child_process cmd = CHILD_PROCESS_INIT;

  int status;

  if (use_pager == -1 && !is_builtin(argv[0]))

    use_pager = check_pager_config(argv[0]);

  commit_pager_choice();

  strvec_pushf(&cmd.args, "git-%s", argv[0]);

  strvec_pushv(&cmd.args, argv + 1);

  cmd.clean_on_exit = 1;

  cmd.wait_after_clean = 1;

  cmd.silent_exec_failure = 1;

  cmd.trace2_child_class = "dashed";

  trace2_cmd_name("_run_dashed_");

  /*

   * The code in run_command() logs trace2 child_start/child_exit

   * events, so we do not need to report exec/exec_result events here.

   */

  trace_argv_printf(cmd.args.v, "trace: exec:");

  /*

   * If we fail because the command is not found, it is

   * OK to return. Otherwise, we just pass along the status code,

   * or our usual generic code if we were not even able to exec

   * the program.

   */

  status = run_command(&cmd);

  /*

   * If the child process ran and we are now going to exit, emit a

   * generic string as our trace2 command verb to indicate that we

   * launched a dashed command.

   */

  if (status >= 0)

    exit(status);

  else if (errno != ENOENT)

    exit(128);

}

static int run_argv(int *argcp, const char ***argv)

{

  int done_alias = 0;

  struct string_list cmd_list = STRING_LIST_INIT_NODUP;

  struct string_list_item *seen;

  while (1) {

    /*

     * If we tried alias and futzed with our environment,

     * it no longer is safe to invoke builtins directly in

     * general.  We have to spawn them as dashed externals.

     *

     * NEEDSWORK: if we can figure out cases

     * where it is safe to do, we can avoid spawning a new

     * process.

     */

    if (!done_alias)

      handle_builtin(*argcp, *argv);

    else if (get_builtin(**argv)) {

      struct child_process cmd = CHILD_PROCESS_INIT;

      int i;

      /*

       * The current process is committed to launching a

       * child process to run the command named in (**argv)

       * and exiting.  Log a generic string as the trace2

       * command verb to indicate this.  Note that the child

       * process will log the actual verb when it runs.

       */

      trace2_cmd_name("_run_git_alias_");

      commit_pager_choice();

      strvec_push(&cmd.args, "git");

      for (i = 0; i < *argcp; i++)

        strvec_push(&cmd.args, (*argv)[i]);

      trace_argv_printf(cmd.args.v, "trace: exec:");

      /*

       * if we fail because the command is not found, it is

       * OK to return. Otherwise, we just pass along the status code.

       */

      cmd.silent_exec_failure = 1;

      cmd.clean_on_exit = 1;

      cmd.wait_after_clean = 1;

      cmd.trace2_child_class = "git_alias";

      i = run_command(&cmd);

      if (i >= 0 || errno != ENOENT)

        exit(i);

      die("could not execute builtin %s", **argv);

    }

    /* .. then try the external ones */

    execv_dashed_external(*argv);

    seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);

    if (seen) {

      int i;

      struct strbuf sb = STRBUF_INIT;

      for (i = 0; i < cmd_list.nr; i++) {

        struct string_list_item *item = &cmd_list.items[i];

        strbuf_addf(&sb, "\n  %s", item->string);

        if (item == seen)

          strbuf_addstr(&sb, " <==");

        else if (i == cmd_list.nr - 1)

          strbuf_addstr(&sb, " ==>");

      }

      die(_("alias loop detected: expansion of '%s' does"

            " not terminate:%s"), cmd_list.items[0].string, sb.buf);

    }

    string_list_append(&cmd_list, *argv[0]);

    /*

     * It could be an alias -- this works around the insanity

     * of overriding "git log" with "git show" by having

     * alias.log = show

     */

    if (!handle_alias(argcp, argv))

      break;

    done_alias = 1;

  }

  string_list_clear(&cmd_list, 0);

  return done_alias;

}

int cmd_main(int argc, const char **argv)

{

  const char *cmd;

  int done_help = 0;

  cmd = argv[0];

  if (!cmd)

    cmd = "git-help";

  else {

    const char *slash = find_last_dir_sep(cmd);

    if (slash)

      cmd = slash + 1;

  }

  trace_command_performance(argv);

  /*

   * "git-xxxx" is the same as "git xxxx", but we obviously:

   *

   *  - cannot take flags in between the "git" and the "xxxx".

   *  - cannot execute it externally (since it would just do

   *    the same thing over again)

   *

   * So we just directly call the builtin handler, and die if

   * that one cannot handle it.

   */