[PATCH 2/5] wlantest: add new cli cmd to dump the help menu for all the supported cmds

[Gokul Sivakumar]

Having a help cli cmd to view all the supported commands is helpful when
running the wlantest_cli manually instead via the python test scripts.

$ wlantest_cli help
commands:
  ping = test connection to wlantest
  terminate = terminate wlantest
  list_bss = get BSS list
  list_sta <BSSID> = get STA list
  flush = drop all collected BSS data
  clear_sta_counters <BSSID> <STA> = clear STA counters
  clear_bss_counters <BSSID> = clear BSS counters
  get_sta_counter <counter> <BSSID> <STA> = get STA counter value
  get_bss_counter <counter> <BSSID> = get BSS counter value
  inject <frame> <prot> <sender> <BSSID> <STA/ff:ff:ff:ff:ff:ff>
  send <prot> <raw frame as hex dump>
  version = get wlantest version
  add_passphrase <passphrase> = add a known passphrase
  add_wepkey <WEP key> = add a known WEP key
  info_sta <field> <BSSID> <STA> = get STA information
  info_bss <field> <BSSID> = get BSS information
  clear_tdls_counters <BSSID> <STA1> <STA2> = clear TDLS counters
  get_tdls_counter <counter> <BSSID> <STA1> <STA2> = get TDLS counter value
  get_bss_counter <counter> <BSSID> = get BSS counter value
  relog = re-open log-file (allow rolling logs)
  get_tx_tid <BSSID> <STA> <TID> = get STA TX TID counter value
  get_rx_tid <BSSID> <STA> <TID> = get STA RX TID counter value
  help = show this usage help

$ wlantest_cli help add_passphrase
commands:
  add_passphrase <passphrase> = add a known passphrase

Signed-off-by: Gokul Sivakumar <gokulkumar792 at gmail.com>
---
 wlantest/wlantest_cli.c | 58 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/wlantest/wlantest_cli.c b/wlantest/wlantest_cli.c
index ad5a48dea..7e0f8444a 100644
--- a/wlantest/wlantest_cli.c
+++ b/wlantest/wlantest_cli.c
@@ -14,6 +14,8 @@
 #include "utils/edit.h"
 #include "wlantest_ctrl.h"
 
+static void print_help(FILE *stream, const char *cmd);
+static char ** wlantest_cli_cmd_list(void);
 
 static int get_cmd_arg_num(const char *str, int pos)
 {
@@ -1566,6 +1568,27 @@ static char ** complete_get_tid(int s, const char *str, int pos)
 }
 
 
+static int wlantest_cli_cmd_help(int s, int argc, char *argv[])
+{
+	print_help(stdout, argc > 0 ? argv[0] : NULL);
+	return 0;
+}
+
+
+static char ** wlantest_cli_complete_help(int s, const char *str, int pos)
+{
+	int arg = get_cmd_arg_num(str, pos);
+	char **res = NULL;
+
+	switch (arg) {
+	case 1:
+		res = wlantest_cli_cmd_list();
+		break;
+	}
+
+	return res;
+}
+
 struct wlantest_cli_cmd {
 	const char *cmd;
 	int (*handler)(int s, int argc, char *argv[]);
@@ -1623,10 +1646,45 @@ static const struct wlantest_cli_cmd wlantest_cli_commands[] = {
 	{ "get_rx_tid", cmd_get_rx_tid,
 	  "<BSSID> <STA> <TID> = get STA RX TID counter value",
 	  complete_get_tid },
+	{ "help", wlantest_cli_cmd_help,
+	  "= show this usage help", wlantest_cli_complete_help },
 	{ NULL, NULL, NULL, NULL }
 };
 
 
+/*
+ * Prints command usage, lines are padded with the specified string.
+ */
+static void print_cmd_help(FILE *stream, const struct wlantest_cli_cmd *cmd,
+			   const char *pad)
+{
+	char c;
+	size_t n;
+
+	if (cmd->usage == NULL)
+		return;
+	fprintf(stream, "%s%s ", pad, cmd->cmd);
+	for (n = 0; (c = cmd->usage[n]); n++) {
+		fprintf(stream, "%c", c);
+		if (c == '\n')
+			fprintf(stream, "%s", pad);
+	}
+	fprintf(stream, "\n");
+}
+
+
+static void print_help(FILE *stream, const char *cmd)
+{
+	int n;
+
+	fprintf(stream, "commands:\n");
+	for (n = 0; wlantest_cli_commands[n].cmd; n++) {
+		if (cmd == NULL || str_starts(wlantest_cli_commands[n].cmd, cmd))
+			print_cmd_help(stream, &wlantest_cli_commands[n], "  ");
+	}
+}
+
+
 static int ctrl_command(int s, int argc, char *argv[])
 {
 	const struct wlantest_cli_cmd *cmd, *match = NULL;
-- 
2.25.1