From e96982fb3158bb8293d2c63b8341cbc0712faca1 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@tuebingen.mpg.de>
Date: Tue, 13 Mar 2018 23:47:11 +0100
Subject: [PATCH] audiod: Implement help --long.

This converts the help command of para_audiod to the generic
lsu_com_help(), adding --long and removing quite a few lines of
duplicated code.  This patch also touches audioc.c since para_audioc
needs to learn to complete the new --long option. Moreover the help
text of the help command is made a bit more useful.
---
 audioc.c                   |  6 +++++
 audiod_command.c           | 53 +++++---------------------------------
 configure.ac               |  1 +
 m4/lls/audiod_cmd.suite.m4 | 10 +++----
 4 files changed, 18 insertions(+), 52 deletions(-)

diff --git a/audioc.c b/audioc.c
index 77a0539d..d9478ab9 100644
--- a/audioc.c
+++ b/audioc.c
@@ -97,6 +97,12 @@ I9E_DUMMY_COMPLETER(term);
 static void help_completer(struct i9e_completion_info *ci,
 		struct i9e_completion_result *result)
 {
+	char *opts[] = {LSG_AUDIOD_CMD_HELP_OPTS, NULL};
+
+	if (ci->word[0] == '-') {
+		i9e_complete_option(opts, ci, result);
+		return;
+	}
 	result->matches = i9e_complete_commands(ci->word, audiod_completers);
 }
 
diff --git a/audiod_command.c b/audiod_command.c
index cb4363b1..bb54dfab 100644
--- a/audiod_command.c
+++ b/audiod_command.c
@@ -13,6 +13,7 @@
 
 #include "audiod.lsg.h"
 #include "para.h"
+#include "lsu.h"
 #include "audiod_cmd.lsg.h"
 #include "list.h"
 #include "sched.h"
@@ -224,59 +225,17 @@ __malloc static char *audiod_status_string(void)
 	return para_strdup(status);
 }
 
-static int dump_commands(int fd)
-{
-	char *buf = para_strdup(""), *tmp = NULL;
-	int i;
-	ssize_t ret;
-	const struct lls_command *cmd;
-
-	for (i = 1; (cmd = lls_cmd(i, audiod_cmd_suite)); i++) {
-		tmp = make_message("%s%s\t%s\n", buf, lls_command_name(cmd),
-			lls_purpose(cmd));
-		free(buf);
-		buf = tmp;
-	}
-	ret = client_write(fd, buf);
-	free(buf);
-	return ret;
-}
-
 static int com_help(int fd, struct lls_parse_result *lpr)
 {
+	char *buf;
 	int ret;
-	char *buf, *errctx;
-	const struct lls_command *cmd;
+	const struct lls_opt_result *r =
+		lls_opt_result(LSG_AUDIOD_CMD_HELP_OPT_LONG, lpr);
+	bool long_help = lls_opt_given(r);
 
-	ret = lls(lls_check_arg_count(lpr, 0, 1, &errctx));
-	if (ret < 0) {
-		if (errctx) {
-			buf = make_message("%s\n", errctx);
-			client_write(fd, buf);
-			free(buf);
-			free(errctx);
-		}
-		return ret;
-	}
-	if (lls_num_inputs(lpr) == 0)
-		return dump_commands(fd);
-	ret = lls(lls_lookup_subcmd(lls_input(0, lpr), audiod_cmd_suite,
-		&errctx));
-	if (ret < 0) {
-		buf = make_message("%s: %s\nAvailable commands:\n", errctx?
-			errctx : lls_input(0, lpr), para_strerror(-ret));
-		if (client_write(fd, buf) >= 0)
-			dump_commands(fd);
-		free(errctx);
-		free(buf);
-		goto out;
-	}
-	cmd = lls_cmd(ret, audiod_cmd_suite);
-	buf = lls_long_help(cmd);
-	assert(buf);
+	lsu_com_help(long_help, lpr, audiod_cmd_suite, NULL, &buf, NULL);
 	ret = client_write(fd, buf);
 	free(buf);
-out:
 	return ret < 0? ret : 0;
 }
 EXPORT_AUDIOD_CMD_HANDLER(help)
diff --git a/configure.ac b/configure.ac
index 060889f4..80671ad5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -487,6 +487,7 @@ if test -n "$CRYPTOLIB"; then
 		wmadec_filter
 		buffer_tree
 		sync_filter
+		lsu
 	"
 	if test "$CRYPTOLIB" = openssl; then
 		audiod_errlist_objs="$audiod_errlist_objs crypt"
diff --git a/m4/lls/audiod_cmd.suite.m4 b/m4/lls/audiod_cmd.suite.m4
index 11de9872..80ae2e42 100644
--- a/m4/lls/audiod_cmd.suite.m4
+++ b/m4/lls/audiod_cmd.suite.m4
@@ -7,14 +7,14 @@ caption = list of audiod commands
 	[/description]
 
 [subcommand help]
-	purpose = display command list or help for given command
+	purpose = list available commands or print command-specific help
 	non-opts-name = [subcommand]
 	[description]
-		When I was younger, so much younger than today, I never needed
-		anybody's help in any way. But now these days are gone, I'm not so self
-		assured. Now I find I've changed my mind and opened up the doors. --
-		Beatles: Help
+		When executed without any arguments, the available audiod commands
+		are listed. Otherwise, if the first argument is the name of an audiod
+		command, the description of this command is shown.
 	[/description]
+	m4_include(`long-help.m4')
 
 [subcommand grab]
 	purpose = grab the audio stream
-- 
2.39.5