C++ commit_pager_choice函数代码示例

static void execv_dashed_external(const char **argv)
{
	struct child_process cmd = CHILD_PROCESS_INIT;
	int status;

	if (get_super_prefix())
		die("%s doesn't support --super-prefix", argv[0]);

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

	argv_array_pushf(&cmd.args, "git-%s", argv[0]);
	argv_array_pushv(&cmd.args, argv + 1);
	cmd.clean_on_exit = 1;
	cmd.wait_after_clean = 1;
	cmd.silent_exec_failure = 1;

	trace_argv_printf(cmd.args.argv, "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 (status >= 0)
		exit(status);
	else if (errno != ENOENT)
		exit(128);
}

static void execv_dashed_external(const char **argv)
{
	struct strbuf cmd = STRBUF_INIT;
	const char *tmp;
	int status;

	commit_pager_choice();

	strbuf_addf(&cmd, "git-%s", argv[0]);

	/*
	 * argv[0] must be the git command, but the argv array
	 * belongs to the caller, and may be reused in
	 * subsequent loop iterations. Save argv[0] and
	 * restore it on error.
	 */
	tmp = argv[0];
	argv[0] = cmd.buf;

	trace_argv_printf(argv, "trace: exec:");

	/*
	 * if we fail because the command is not found, it is
	 * OK to return. Otherwise, we just pass along the status code.
	 */
	status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE);
	if (status >= 0 || errno != ENOENT)
		exit(status);

	argv[0] = tmp;

	strbuf_release(&cmd);
}

static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status, help;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	help = argc == 2 && !strcmp(argv[1], "-h");
	if (!help) {
		if (p->option & RUN_SETUP)
			prefix = setup_git_directory();
		else if (p->option & RUN_SETUP_GENTLY) {
			int nongit_ok;
			prefix = setup_git_directory_gently(&nongit_ok);
		}

		if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
			use_pager = check_pager_config(p->cmd);
		if (use_pager == -1 && p->option & USE_PAGER)
			use_pager = 1;

		if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
		    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
			trace_repo_setup(prefix);
	}
	commit_pager_choice();

	if (!help && get_super_prefix()) {
		if (!(p->option & SUPPORT_SUPER_PREFIX))
			die("%s doesn't support --super-prefix", p->cmd);
		if (prefix)
			die("can't use --super-prefix from a subdirectory");
	}

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

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

	status = p->fn(argc, argv, prefix);
	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 int run_argv(int *argcp, const char ***argv)
{
	int done_alias = 0;

	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 argv_array args = ARGV_ARRAY_INIT;
			int i;

			if (get_super_prefix())
				die("%s doesn't support --super-prefix", **argv);

			commit_pager_choice();

			argv_array_push(&args, "git");
			for (i = 0; i < *argcp; i++)
				argv_array_push(&args, (*argv)[i]);

			trace_argv_printf(args.argv, "trace: exec:");

			/*
			 * if we fail because the command is not found, it is
			 * OK to return. Otherwise, we just pass along the status code.
			 */
			i = run_command_v_opt(args.argv, RUN_SILENT_EXEC_FAILURE |
					      RUN_CLEAN_ON_EXIT);
			if (i >= 0 || errno != ENOENT)
				exit(i);
			die("could not execute builtin %s", **argv);
		}

		/* .. then try the external ones */
		execv_dashed_external(*argv);

		/* It could be an alias -- this works around the insanity
		 * of overriding "git log" with "git show" by having
		 * alias.log = show
		 */
		if (done_alias)
			break;
		if (!handle_alias(argcp, argv))
			break;
		done_alias = 1;
	}

	return done_alias;
}

static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status;
	struct stat st;
	const char *prefix;
	char sbuf[STRERR_BUFSIZE];

	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; /* setup_perf_directory(); */

	if (use_browser == -1)
		use_browser = check_browser_config(p->cmd);

	if (use_pager == -1 && p->option & RUN_SETUP)
		use_pager = check_pager_config(p->cmd);
	if (use_pager == -1 && p->option & USE_PAGER)
		use_pager = 1;
	commit_pager_choice();

	perf_env__set_cmdline(&perf_env, argc, argv);
	status = p->fn(argc, argv, prefix);
	perf_config__exit();
	exit_browser(status);
	perf_env__exit(&perf_env);
	bpf__clear();

	if (status)
		return status & 0xff;

	/* 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;

	status = 1;
	/* Check for ENOSPC and EIO errors.. */
	if (fflush(stdout)) {
		fprintf(stderr, "write failure on standard output: %s",
			str_error_r(errno, sbuf, sizeof(sbuf)));
		goto out;
	}
	if (ferror(stdout)) {
		fprintf(stderr, "unknown write failure on standard output");
		goto out;
	}
	if (fclose(stdout)) {
		fprintf(stderr, "close failed on standard output: %s",
			str_error_r(errno, sbuf, sizeof(sbuf)));
		goto out;
	}
	status = 0;
out:
	return status;
}

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 run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status, help;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	help = argc == 2 && !strcmp(argv[1], "-h");
	if (!help) {
		if (p->option & RUN_SETUP)
			prefix = setup_git_directory();
		if (p->option & RUN_SETUP_GENTLY) {
			int nongit_ok;
			prefix = setup_git_directory_gently(&nongit_ok);
		}

		if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
			use_pager = check_pager_config(p->cmd);
		if (use_pager == -1 && p->option & USE_PAGER)
			use_pager = 1;
	}
	commit_pager_choice();

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

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

	status = p->fn(argc, argv, prefix);
	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 int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; /* setup_perf_directory(); */

	if (use_browser == -1)
		use_browser = check_tui_config(p->cmd);

	if (use_pager == -1 && p->option & RUN_SETUP)
		use_pager = check_pager_config(p->cmd);
	if (use_pager == -1 && p->option & USE_PAGER)
		use_pager = 1;
	commit_pager_choice();
	set_debugfs_path();

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

	if (status)
		return status & 0xff;

	/* 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("write failure on standard output: %s", strerror(errno));
	if (ferror(stdout))
		die("unknown write failure on standard output");
	if (fclose(stdout))
		die("close failed on standard output: %s", strerror(errno));
	return 0;
}

static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
	int status;
	struct stat st;
	const char *prefix;

	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; 

	if (use_browser == -1)
		use_browser = check_tui_config(p->cmd);

	if (use_pager == -1 && p->option & RUN_SETUP)
		use_pager = check_pager_config(p->cmd);
	if (use_pager == -1 && p->option & USE_PAGER)
		use_pager = 1;
	commit_pager_choice();

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

	if (status)
		return status & 0xff;

	
	if (fstat(fileno(stdout), &st))
		return 0;
	
	if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
		return 0;

	
	if (fflush(stdout))
		die("write failure on standard output: %s", strerror(errno));
	if (ferror(stdout))
		die("unknown write failure on standard output");
	if (fclose(stdout))
		die("close failed on standard output: %s", strerror(errno));
	return 0;
}

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;
	}

	/*
	 * wait_for_pager_atexit will close stdout/stderr so it needs to be
	 * registered first so that it will execute last and not close the
	 * handles until all other atexit handlers have finished
	 */
	atexit(wait_for_pager_atexit);
	trace_command_performance(argv);
	atexit(post_command_hook_atexit);

	/*
	 * "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.
	 */
	if (skip_prefix(cmd, "git-", &cmd)) {
		argv[0] = cmd;
		handle_builtin(argc, argv);
		die("cannot handle %s as a builtin", cmd);
	}

	/* Look for flags.. */
	argv++;
	argc--;
	handle_options(&argv, &argc, NULL);
	if (argc > 0) {
		/* translate --help and --version into commands */
		skip_prefix(argv[0], "--", &argv[0]);
	} else {
		/* The user didn't specify a command; give them help */
		commit_pager_choice();
		if (run_pre_command_hook(argv))
			die("pre-command hook aborted command");
		printf("usage: %s\n\n", git_usage_string);
		list_common_cmds_help();
		printf("\n%s\n", _(git_more_info_string));
		exit_code = 1;
		run_post_command_hook();
		exit(exit_code);
	}
	cmd = argv[0];

	/*
	 * We use PATH to find git commands, but we prepend some higher
	 * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
	 * environment, and the $(gitexecdir) from the Makefile at build
	 * time.
	 */
	setup_path();

	while (1) {
		int was_alias = run_argv(&argc, &argv);
		if (errno != ENOENT)
			break;
		if (was_alias) {
			fprintf(stderr, _("expansion of alias '%s' failed; "
					  "'%s' is not a git command\n"),
				cmd, argv[0]);
			exit(1);
		}
		if (!done_help) {
			cmd = argv[0] = help_unknown_cmd(cmd);
			done_help = 1;
		} else
			break;
	}

	fprintf(stderr, _("failed to run command '%s': %s\n"),
		cmd, strerror(errno));

	return 1;
}

static int handle_alias(int *argcp, const char ***argv)
{
	int envchanged = 0, ret = 0, saved_errno = errno;
	const char *subdir;
	int count, option_count;
	const char **new_argv;
	const char *alias_command;
	char *alias_string;
	int unused_nongit;

	subdir = setup_git_directory_gently(&unused_nongit);

	alias_command = (*argv)[0];
	alias_string = alias_lookup(alias_command);
	if (alias_string) {
		if (alias_string[0] == '!') {
			const char **alias_argv;
			int argc = *argcp, i;

			commit_pager_choice();

			/* build alias_argv */
			alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
			alias_argv[0] = alias_string + 1;
			for (i = 1; i < argc; ++i)
				alias_argv[i] = (*argv)[i];
			alias_argv[argc] = NULL;

			ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
			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);
		memmove(new_argv - option_count, new_argv,
				count * sizeof(char *));
		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);

		new_argv = xrealloc(new_argv, sizeof(char *) *
				    (count + *argcp));
		/* insert after command name */
		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);

		*argv = new_argv;
		*argcp += count - 1;

		ret = 1;
	}

	if (subdir && chdir(subdir))
		die_errno("Cannot change to '%s'", subdir);

	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;

	prefix = NULL;
	help = argc == 2 && !strcmp(argv[1], "-h");
	if (!help) {
		if (p->option & RUN_SETUP)
			prefix = setup_git_directory();
		else if (p->option & RUN_SETUP_GENTLY) {
			int nongit_ok;
			prefix = setup_git_directory_gently(&nongit_ok);
		}

		if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
		    !(p->option & DELAY_PAGER_CONFIG))
			use_pager = check_pager_config(p->cmd);
		if (use_pager == -1 && p->option & USE_PAGER)
			use_pager = 1;

		if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
		    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
			trace_repo_setup(prefix);
	}
	commit_pager_choice();

	if (!help && get_super_prefix()) {
		if (!(p->option & SUPPORT_SUPER_PREFIX))
			die("%s doesn't support --super-prefix", p->cmd);
	}

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

	if (run_pre_command_hook(argv))
		die("pre-command hook aborted command");

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

	/*
	 * Validate the state of the cache entries in the index before and
	 * after running the command. Validation is only performed if the
	 * appropriate environment variable is set.
	 */
	validate_cache_entries(&the_index);
	exit_code = status = p->fn(argc, argv, prefix);
	validate_cache_entries(&the_index);
	if (status)
		return status;

	run_post_command_hook();

	/* 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 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 (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;
			argv_array_push(&child.args, alias_string + 1);
			argv_array_pushv(&child.args, (*argv) + 1);

			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);
		memmove(new_argv - option_count, new_argv,
				count * sizeof(char *));
		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 */
		memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);

		*argv = new_argv;
		*argcp += count - 1;

		ret = 1;
	}

	errno = saved_errno;

	return ret;
}

int main(int argc, char **av)
{
	const char **argv = (const char **) av;
	const char *cmd;

	startup_info = &git_startup_info;

	cmd = git_extract_argv0_path(argv[0]);
	if (!cmd)
		cmd = "git-help";

	/*
	 * Always open file descriptors 0/1/2 to avoid clobbering files
	 * in die().  It also avoids messing up when the pipes are dup'ed
	 * onto stdin/stdout/stderr in the child processes we spawn.
	 */
	sanitize_stdfds();

	git_setup_gettext();

	/*
	 * "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.
	 */
	if (starts_with(cmd, "git-")) {
		cmd += 4;
		argv[0] = cmd;
		handle_builtin(argc, argv);
		die("cannot handle %s as a builtin", cmd);
	}

	/* Look for flags.. */
	argv++;
	argc--;
	handle_options(&argv, &argc, NULL);
	if (argc > 0) {
		if (starts_with(argv[0], "--"))
			argv[0] += 2;
	} else {
		/* The user didn't specify a command; give them help */
		commit_pager_choice();
		printf("usage: %s\n\n", git_usage_string);
		list_common_cmds_help();
		printf("\n%s\n", _(git_more_info_string));
		exit(1);
	}
	cmd = argv[0];

	/*
	 * We use PATH to find git commands, but we prepend some higher
	 * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
	 * environment, and the $(gitexecdir) from the Makefile at build
	 * time.
	 */
	setup_path();

	while (1) {
		static int done_help = 0;
		static int was_alias = 0;
		was_alias = run_argv(&argc, &argv);
		if (errno != ENOENT)
			break;
		if (was_alias) {
			fprintf(stderr, "Expansion of alias '%s' failed; "
				"'%s' is not a git command\n",
				cmd, argv[0]);
			exit(1);
		}
		if (!done_help) {
			cmd = argv[0] = help_unknown_cmd(cmd);
			done_help = 1;
		} else
			break;
	}

	fprintf(stderr, "Failed to run command '%s': %s\n",
		cmd, strerror(errno));

	return 1;
}

int main(int argc, const char **argv)
{
	const char *cmd;

	cmd = perf_extract_argv0_path(argv[0]);
	if (!cmd)
		cmd = "perf-help";
	
	debugfs_mount(NULL);
	if (!prefixcmp(cmd, "perf-")) {
		cmd += 5;
		argv[0] = cmd;
		handle_internal_command(argc, argv);
		die("cannot handle %s internally", cmd);
	}

	
	argv++;
	argc--;
	handle_options(&argv, &argc, NULL);
	commit_pager_choice();
	set_buildid_dir();

	if (argc > 0) {
		if (!prefixcmp(argv[0], "--"))
			argv[0] += 2;
	} else {
		
		printf("\n usage: %s\n\n", perf_usage_string);
		list_common_cmds_help();
		printf("\n %s\n\n", perf_more_info_string);
		exit(1);
	}
	cmd = argv[0];

	setup_path();
	pthread__block_sigwinch();

	while (1) {
		static int done_help;
		static int was_alias;

		was_alias = run_argv(&argc, &argv);
		if (errno != ENOENT)
			break;

		if (was_alias) {
			fprintf(stderr, "Expansion of alias '%s' failed; "
				"'%s' is not a perf-command\n",
				cmd, argv[0]);
			exit(1);
		}
		if (!done_help) {
			cmd = argv[0] = help_unknown_cmd(cmd);
			done_help = 1;
		} else
			break;
	}

	fprintf(stderr, "Failed to run command '%s': %s\n",
		cmd, strerror(errno));

	return 1;
}