Add option_parser_print_usage

Signed-off-by: Jim Ramsay <i.am@jimramsay.com>

include/option-parser.h

@@ -50,11 +50,16 @@ struct option_parser {
 void option_parser_init(struct option_parser* self,
 		const struct wv_option* options);
 
+void option_parser_print_usage(struct option_parser* self, FILE* stream);
+
 int option_parser_print_arguments(struct option_parser* self, FILE* stream);
 
 void option_parser_print_options(struct option_parser* self, FILE* stream);
 
 int option_parser_parse(struct option_parser* self, int argc,
 		const char* const* argv);
+
 const char* option_parser_get_value(const struct option_parser* self,
 		const char* name);
+const char* option_parser_get_value_no_default(const struct option_parser* self,
+		const char* name);

src/ctl-client.c

@@ -738,12 +738,9 @@ static int print_command_usage(struct ctl_client* self,
 		WARN("No such command");
 		return 1;
 	}
-	printf("Usage: wayvncctl [options] %s ", info->name);
+	printf("Usage: wayvncctl [options] %s", info->name);
-	for (int i = 0; i < cmd_options->n_opts; ++i)
+	option_parser_print_usage(cmd_options, stdout);
-		if (cmd_options->options[i].positional)
+	printf("\n\n");
-			printf("<%s> ", cmd_options->options[i].positional);
-
-	printf("[parameters]\n\n");
 	table_printer_indent_and_reflow_text(stdout, info->description, 80, 0, 0);
 	printf("\n");
 	if (option_parser_print_arguments(cmd_options, stdout))

src/main.c

@@ -66,6 +66,9 @@
 #define DEFAULT_ADDRESS "127.0.0.1"
 #define DEFAULT_PORT 5900
 
+#define XSTR(x) STR(x)
+#define STR(x) #x
+
 #define MAYBE_UNUSED __attribute__((unused))
 
 struct wayvnc {
@@ -907,15 +910,14 @@ void on_capture_done(struct screencopy* sc)
 
 int wayvnc_usage(struct option_parser* parser, FILE* stream, int rc)
 {
-	static const char* usage =
+	fputs("Usage: wayvnc", stream);
-"Usage: wayvnc [options] [<address> [<port>]]\n"
+	option_parser_print_usage(parser, stream);
-"\n"
+	fputs("\n\n", stream);
-"Starts a VNC server for $WAYLAND_DISPLAY";
+	fprintf(stream, "Starts a VNC server for $WAYLAND_DISPLAY\n\n");
-	fprintf(stream, "%s\n\n", usage);
 	if (option_parser_print_arguments(parser, stream))
-		fprintf(stream, "\n");
+		fputc('\n', stream);
 	option_parser_print_options(parser, stream);
-	fprintf(stream, "\n");
+	fputc('\n', stream);
 	return rc;
 }
 
@@ -1270,9 +1272,11 @@ int main(int argc, char* argv[])
 
 	static const struct wv_option opts[] = {
 		{ .positional = "address",
-		  .help = "The IP address or unix socket path to listen on. Default: 127.0.0.1" },
+		  .help = "The IP address or unix socket path to listen on.",
+		  .default_ = DEFAULT_ADDRESS},
 		{ .positional = "port",
-		  .help = "The TCP port to listen on. Default: 5900" },
+		  .help = "The TCP port to listen on.",
+		  .default_ = XSTR(DEFAULT_PORT)},
 		{ 'C', "config", "<path>",
 		  "Select a config file." },
 		{ 'g', "gpu", NULL,
@@ -1305,7 +1309,7 @@ int main(int argc, char* argv[])
 		  .default_ = "warning" },
 		{ 'h', "help", NULL,
 		  "Get help (this text)." },
-		{ '\0', NULL, NULL, NULL }
+		{}
 	};
 
 	struct option_parser option_parser;
@@ -1344,8 +1348,10 @@ int main(int argc, char* argv[])
 
 	nvnc_set_log_level(log_level);
 
-	address = option_parser_get_value(&option_parser, "address");
+	// Only check for explicitly-set values here (defaults applied below)
-	const char* port_str = option_parser_get_value(&option_parser, "port");
+	address = option_parser_get_value_no_default(&option_parser, "address");
+	const char* port_str = option_parser_get_value_no_default(&option_parser,
+			"port");
 	if (port_str)
 		port = atoi(port_str);
 

src/option-parser.c

@@ -23,6 +23,7 @@
 #include <stdbool.h>
 #include <assert.h>
 #include <sys/param.h>
+#include <ctype.h>
 
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
 
@@ -105,6 +106,39 @@ void option_parser_print_options(struct option_parser* self, FILE* stream)
 		format_option(&printer, &self->options[i]);
 }
 
+static void print_string_tolower(FILE* stream, const char *src)
+{
+	for (const char* c = src; *c != '\0'; c++)
+		fprintf(stream, "%c", tolower(*c));
+}
+
+void option_parser_print_usage(struct option_parser* self, FILE* stream)
+{
+	fprintf(stream, " [");
+	print_string_tolower(stream, self->name);
+	fprintf(stream, "]");
+	int optional_paren_count = 0;
+	for (int i = 0; i < self->n_opts; ++i) {
+		const struct wv_option* opt = &self->options[i];
+		if (!opt->positional)
+			continue;
+		const char* open = "<";
+		const char* close = ">";
+		if (opt->default_) {
+			open = "[";
+			close = ""; // Closed via optional_paren_count loop below
+			optional_paren_count++;
+		} else {
+			// Enforce there must be NO non-optional args after
+			// we've processed at least one optional arg
+			assert(optional_paren_count == 0);
+		}
+		fprintf(stream, " %s%s%s", open, opt->positional, close);
+	}
+	for (int i = 0; i < optional_paren_count; ++i)
+		fprintf(stream, "]");
+}
+
 int option_parser_print_arguments(struct option_parser* self, FILE* stream)
 {
 	size_t max_arg = 0;
@@ -168,6 +202,19 @@ static const struct wv_option* find_positional_option(
 	return NULL;
 }
 
+static const struct wv_option* find_positional_option_by_name(
+		const struct option_parser* self, const char*name)
+{
+	for (int i = 0; i < self->n_opts; ++i) {
+		const struct wv_option* opt = &self->options[i];
+		if (!opt->positional)
+			continue;
+		if (strcmp(opt->positional, name) == 0)
+			return opt;
+	}
+	return NULL;
+}
+
 static int append_value(struct option_parser* self,
 		const struct wv_option* option, const char* value)
 {
@@ -317,7 +364,7 @@ int option_parser_parse(struct option_parser* self, int argc,
 	return 0;
 }
 
-const char* option_parser_get_value(const struct option_parser* self,
+const char* option_parser_get_value_no_default(const struct option_parser* self,
 		const char* name)
 {
 	const struct wv_option* opt;
@@ -340,6 +387,18 @@ const char* option_parser_get_value(const struct option_parser* self,
 			return value->value;
 	}
 
+	return NULL;
+}
+
+const char* option_parser_get_value(const struct option_parser* self,
+		const char* name)
+{
+	const char* value = option_parser_get_value_no_default(self, name);
+	if (value)
+		return value;
+
+	bool is_short = name[0] && !name[1];
+	const struct wv_option* opt;
 	if (is_short) {
 		opt = find_short_option(self, name[0]);
 		if (opt)
@@ -348,9 +407,10 @@ const char* option_parser_get_value(const struct option_parser* self,
 		opt = find_long_option(self, name);
 		if (opt)
 			return opt->default_;
+		opt = find_positional_option_by_name(self, name);
+		if (opt)
+			return opt->default_;
 	}
 
-	// TODO: Add positional option?
-
 	return NULL;
 }

src/wayvncctl.c

@@ -43,13 +43,12 @@ struct wayvncctl {
 
 static int wayvncctl_usage(FILE* stream, struct option_parser* options, int rc)
 {
-	static const char* usage =
+	fputs("Usage: wayvncctl", stream);
-"Usage: wayvncctl [options] <command> [parameters]\n"
+	option_parser_print_usage(options, stream);
-"\n"
+	fputs(" [parameters]\n\n", stream);
-"Connects to and interacts with a running wayvnc instance.";
+	fputs("Connects to and interacts with a running wayvnc instance.\n\n", stream);
-	fprintf(stream, "%s\n\n", usage);
 	option_parser_print_options(options, stream);
-	fprintf(stream, "\n");
+	fputc('\n', stream);
 	ctl_client_print_command_list(stream);
 	return rc;
 }

test/option-parser-test.c

@@ -15,6 +15,13 @@ static const struct wv_option options[] = {
 	{ },
 };
 
+static const struct wv_option default_options[] = {
+	{ .positional = "first" },
+	{ .positional = "second", .default_ = "second_default" },
+	{ 'v', "value-option", "value", "Description of v", .default_ = "v_default" },
+	{ },
+};
+
 static int test_simple(void)
 {
 	struct option_parser parser;
@@ -227,6 +234,61 @@ static int test_subcommand_with_arguments(void)
 	return 0;
 }
 
+static int test_defaults_not_set(void)
+{
+	struct option_parser parser;
+	option_parser_init(&parser, default_options);
+	const char* argv[] = {
+		"executable",
+		"pos 1",
+	};
+
+	ASSERT_INT_EQ(0, option_parser_parse(&parser, ARRAY_SIZE(argv), argv));
+	ASSERT_STR_EQ("pos 1", option_parser_get_value(&parser, "first"));
+
+	ASSERT_STR_EQ("second_default", option_parser_get_value(&parser, "second"));
+	ASSERT_FALSE(option_parser_get_value_no_default(&parser, "second"));
+
+	ASSERT_STR_EQ("v_default", option_parser_get_value(&parser, "value-option"));
+	ASSERT_FALSE(option_parser_get_value_no_default(&parser, "value-option"));
+	ASSERT_STR_EQ("v_default", option_parser_get_value(&parser, "v"));
+	ASSERT_FALSE(option_parser_get_value_no_default(&parser, "v"));
+
+	ASSERT_INT_EQ(0, parser.remaining_argc);
+	ASSERT_FALSE(parser.remaining_argv);
+
+	return 0;
+}
+
+static int test_defaults_overridden(void)
+{
+	struct option_parser parser;
+	option_parser_init(&parser, default_options);
+	const char* argv[] = {
+		"executable",
+		"pos 1",
+		"pos 2",
+		"-v",
+		"v_set",
+	};
+
+	ASSERT_INT_EQ(0, option_parser_parse(&parser, ARRAY_SIZE(argv), argv));
+	ASSERT_STR_EQ("pos 1", option_parser_get_value(&parser, "first"));
+
+	ASSERT_STR_EQ("pos 2", option_parser_get_value(&parser, "second"));
+	ASSERT_STR_EQ("pos 2", option_parser_get_value_no_default(&parser, "second"));
+
+	ASSERT_STR_EQ("v_set", option_parser_get_value(&parser, "value-option"));
+	ASSERT_STR_EQ("v_set", option_parser_get_value_no_default(&parser, "value-option"));
+	ASSERT_STR_EQ("v_set", option_parser_get_value(&parser, "v"));
+	ASSERT_STR_EQ("v_set", option_parser_get_value_no_default(&parser, "v"));
+
+	ASSERT_INT_EQ(0, parser.remaining_argc);
+	ASSERT_FALSE(parser.remaining_argv);
+
+	return 0;
+}
+
 int main()
 {
 	int r = 0;
@@ -246,5 +308,7 @@ int main()
 	RUN_TEST(test_missing_long_value);
 	RUN_TEST(test_subcommand_without_arguments);
 	RUN_TEST(test_subcommand_with_arguments);
+	RUN_TEST(test_defaults_not_set);
+	RUN_TEST(test_defaults_overridden);
 	return r;
 }