Better help for console commands

Additional help messages and usage are gated by
CONFIG_CONSOLE_CMDHELP, so we can turn it on if there's space (adds
about 3KB to image size) and turn it off when there isn't.

Signed-off-by: Randall Spangler <rspangler@chromium.org>

BUG=none
TEST=manual

1) help
2) help list
3) help gpioset
4) gpioset -> wrong number of params
5) gpioset fred 0 -> param1 bad
6) gpioset cpu_prochot fred -> param2 bad

Change-Id: Ibe99f37212020f763ebe65a068e6aa83a809a370

1 files changed, 74 insertions, 24 deletions

diff --git a/common/console.c b/common/console.c
index 16a17fade7..e1c1365f11 100644
--- a/common/console.c
+++ b/common/console.c
@@ -124,8 +124,8 @@ static int split_words(char *input, int max_argc, int *argc, char **argv)
 }
 
 
-/* Finds a command by name.  Returns the command structure, or NULL if
- * no match found. */
+/* Find a command by name.  Returns the command structure, or NULL if no match
+ * found. */
 static const struct console_command *find_command(char *name)
 {
 	const struct console_command *cmd, *match = NULL;
@@ -143,14 +143,14 @@ static const struct console_command *find_command(char *name)
 }
 
 
-/* Handles a line of input containing a single command.
- *
- * Modifies the input string during parsing. */
+/* Handle a line of input containing a single command.  Modifies the input
+ * string during parsing. */
 static int handle_command(char *input)
 {
 	const struct console_command *cmd;
 	char *argv[MAX_ARGS_PER_COMMAND];
 	int argc = 0;
+	int rv;
 
 	/* Split input into words.  Ignore words past our limit. */
 	split_words(input, MAX_ARGS_PER_COMMAND, &argc, argv);
@@ -160,11 +160,32 @@ static int handle_command(char *input)
 		return EC_SUCCESS;
 
 	cmd = find_command(argv[0]);
-	if (cmd)
-		return cmd->handler(argc, argv);
+	if (!cmd) {
+		ccprintf("Command '%s' not found or ambiguous.\n", argv[0]);
+		return EC_ERROR_UNKNOWN;
+	}
 
-	ccprintf("Command '%s' not found or ambiguous.\n", argv[0]);
-	return EC_ERROR_UNKNOWN;
+	rv = cmd->handler(argc, argv);
+	if (rv == EC_SUCCESS)
+		return rv;
+
+	/* Print more info for errors */
+	if (rv == EC_ERROR_INVAL)
+		ccputs("Command usage/param invalid.\n");
+	else if (rv == EC_ERROR_PARAM_COUNT)
+		ccputs("Wrong number of params.\n");
+	else if (rv >= EC_ERROR_PARAM1 && rv <= EC_ERROR_PARAM9)
+		ccprintf("Parameter %d invalid.\n", rv - EC_ERROR_PARAM1 + 1);
+	else if (rv != EC_SUCCESS) {
+		ccprintf("Command returned error %d\n", rv);
+		return rv;
+	}
+
+#ifdef CONFIG_CONSOLE_CMDHELP
+	if (cmd->argdesc)
+		ccprintf("Usage: %s %s\n", cmd->name, cmd->argdesc);
+#endif
+	return rv;
 }
 
 
@@ -184,20 +205,11 @@ static int console_init(void)
 /* handle a console command */
 static void console_process(void)
 {
-        int rv;
-
 	/* Process all the pending commands.  Need to do this all at once
 	 * since our interrupt may have been triggered multiple times. */
-	/* TODO: Go to sleep briefly between commands to give lower
-	 * priority tasks a chance to run? */
 	while (uart_peek('\n') >= 0) {
 		uart_gets(input_buf, sizeof(input_buf));
-
-		rv = handle_command(input_buf);
-		if (rv == EC_ERROR_INVAL)
-			ccputs("Command usage/param invalid.\n");
-		else if (rv != EC_SUCCESS)
-			ccprintf("Command returned error %d\n", rv);
+		handle_command(input_buf);
 		ccputs(PROMPT);
 	}
 }
@@ -216,7 +228,7 @@ void console_task(void)
 
 	while (1) {
 		console_process();
-		/* wait for the next command message */
+		/* Wait for the next command message */
 		task_wait_event(-1);
 	}
 }
@@ -233,8 +245,35 @@ static int command_help(int argc, char **argv)
 	const int rows = (ncmds + cols - 1) / cols;
 	int i, j;
 
-	ccputs("Known commands:\n");
+#ifdef CONFIG_CONSOLE_CMDHELP
+	if (argc == 2) {
+		const struct console_command *cmd;
+
+		if (!strcasecmp(argv[1], "list")) {
+			ccputs("Known commands:\n");
+			for (i = 0; i < ncmds; i++) {
+				ccprintf("  %-15s%s\n",
+					 __cmds[i].name, __cmds[i].shorthelp);
+				cflush();
+			}
+			ccputs("HELP CMD = help on CMD.\n");
+			return EC_SUCCESS;
+		}
+		cmd = find_command(argv[1]);
+		if (!cmd) {
+			ccprintf("Command '%s' not found or ambiguous.\n",
+				 argv[1]);
+			return EC_ERROR_UNKNOWN;
+		}
+		ccprintf("Usage: %s %s\n", cmd->name,
+			 (cmd->argdesc ? cmd->argdesc : ""));
+		if (cmd->shorthelp)
+			ccprintf("%s\n", cmd->shorthelp);
+		return EC_SUCCESS;
+	}
+#endif
 
+	ccputs("Known commands:\n");
 	for (i = 0; i < rows; i++) {
 		ccputs("  ");
 		for (j = 0; j < cols; j++) {
@@ -247,9 +286,17 @@ static int command_help(int argc, char **argv)
 		cflush();
 	}
 
+#ifdef CONFIG_CONSOLE_CMDHELP
+	ccputs("HELP LIST = more info; ");
+	ccputs("HELP CMD = help on CMD.\n");
+#endif
+
 	return EC_SUCCESS;
 }
-DECLARE_CONSOLE_COMMAND(help, command_help);
+DECLARE_CONSOLE_COMMAND(help, command_help,
+			"[ list | <name> ]",
+			"Print command help",
+			NULL);
 
 
 /* Set active channels */
@@ -262,7 +309,7 @@ static int command_ch(int argc, char **argv)
 	if (argc == 2) {
 		int m = strtoi(argv[1], &e, 0);
 		if (*e)
-			return EC_ERROR_INVAL;
+			return EC_ERROR_PARAM1;
 
 		/* No disabling the command output channel */
 		channel_mask = m | CC_MASK(CC_COMMAND);
@@ -283,4 +330,7 @@ static int command_ch(int argc, char **argv)
 	}
 	return EC_SUCCESS;
 };
-DECLARE_CONSOLE_COMMAND(chan, command_ch);
+DECLARE_CONSOLE_COMMAND(chan, command_ch,
+			"[mask]",
+			"Get or set console channel mask",
+			NULL);