From: Karl Fleischmann <karl.fleischmann@open-xchange.com>
Date: Thu, 22 Jun 2023 10:18:07 +0000 (+0200)
Subject: doveadm: Process subcommand "--help" options
X-Git-Tag: 2.4.0~2643
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6735fd68b041e3e6a1e4bab6d296fd14b703a18e;p=thirdparty%2Fdovecot%2Fcore.git

doveadm: Process subcommand "--help" options

Arguments are handled individually in different situations when invoking
doveadm with or without subcommands (specifically
doveadm_cmdline_find_with_args() may fail if "help" is passed). To
handle all necessary situtations the command context needs to be
expanded with a variable to differentiate whether a help argument (i.e.
"--help") or a help option (i.e. "help") is given. This is used
subsequently to print the help/usage text to stdout with a successful
return code if requested.
---

diff --git a/src/doveadm/doveadm-cmd-parse.h b/src/doveadm/doveadm-cmd-parse.h
index ce9d15302e..54b2578add 100644
--- a/src/doveadm/doveadm-cmd-parse.h
+++ b/src/doveadm/doveadm-cmd-parse.h
@@ -90,12 +90,19 @@ struct doveadm_cmd_ver2 {
 	const struct doveadm_cmd_param *parameters;
 };
 
+enum doveadm_cmd_ver2_help_requested {
+	DOVEADM_CMD_VER2_NO_HELP,
+	DOVEADM_CMD_VER2_HELP_ARGUMENT,
+	DOVEADM_CMD_VER2_HELP_COMMAND,
+};
+
 struct doveadm_cmd_context {
 	const struct doveadm_cmd_ver2 *cmd; /* for help */
 
 	pool_t pool;
 	int argc;
 	const struct doveadm_cmd_param *argv;
+	enum doveadm_cmd_ver2_help_requested help_requested;
 
 	const char *username;
 	struct ip_addr local_ip, remote_ip;
diff --git a/src/doveadm/doveadm-cmd.c b/src/doveadm/doveadm-cmd.c
index 1f64fd3446..147d172001 100644
--- a/src/doveadm/doveadm-cmd.c
+++ b/src/doveadm/doveadm-cmd.c
@@ -124,17 +124,39 @@ void doveadm_cmds_deinit(void)
 	array_free(&doveadm_cmds_ver2);
 }
 
+static void
+doveadm_cmdline_check_for_help_request(int argc, const char *const argv[],
+				       struct doveadm_cmd_context *cctx) {
+	for (int i = 0; i < argc; i++) {
+		if (strcmp(argv[i], "--") == 0)
+			break;
+
+		if (strcmp(argv[i], "--help") == 0) {
+			cctx->help_requested = DOVEADM_CMD_VER2_HELP_ARGUMENT;
+			break;
+		}
+
+		if (strcmp(argv[i], "help") == 0) {
+			cctx->help_requested = DOVEADM_CMD_VER2_HELP_COMMAND;
+			break;
+		}
+	}
+}
+
 bool doveadm_cmdline_try_run(const char *cmd_name,
 			     int argc, const char *const argv[],
 			     struct doveadm_cmd_context *cctx)
 {
 	const struct doveadm_cmd_ver2 *cmd;
 
+	doveadm_cmdline_check_for_help_request(argc, argv, cctx);
 	cmd = doveadm_cmdline_find_with_args(cmd_name, &argc, &argv);
 	if (cmd == NULL)
 		return FALSE;
 
 	cctx->cmd = cmd;
+	if (cctx->help_requested == DOVEADM_CMD_VER2_HELP_ARGUMENT)
+		return FALSE;
 	if (doveadm_cmdline_run(argc, argv, cctx) < 0)
 		doveadm_exit_code = EX_USAGE;
 	return TRUE;
diff --git a/src/doveadm/doveadm.c b/src/doveadm/doveadm.c
index 30e8c25f36..45d7b54234 100644
--- a/src/doveadm/doveadm.c
+++ b/src/doveadm/doveadm.c
@@ -383,8 +383,16 @@ int main(int argc, char *argv[])
 	cctx->username = getenv("USER");
 
 	if (!doveadm_cmdline_try_run(cmd_name, argc, (const char**)argv, cctx)) {
+		help_requested = cctx->help_requested != DOVEADM_CMD_VER2_NO_HELP;
+		FILE *out = help_requested ? stdout : stderr;
+		int exit_code = help_requested ? EX_OK : EX_USAGE;
+		if (cctx->help_requested == DOVEADM_CMD_VER2_HELP_ARGUMENT &&
+		    cctx->cmd != NULL) {
+			print_usage_and_exit(stdout, cctx->cmd, EX_OK);
+		}
 		if (doveadm_has_subcommands(cmd_name))
-			usage_prefix(stderr, cmd_name, EX_USAGE);
+			usage_prefix(out, cmd_name, exit_code);
+
 		if (doveadm_has_unloaded_plugin(cmd_name)) {
 			i_fatal("Unknown command '%s', but plugin %s exists. "
 				"Try to set mail_plugins=%s",