alsa-utils: axfer: use second argument for transmission direction

axfer/main.c

@@ -70,14 +70,9 @@ static void print_help(void)
 	printf("help\n");
 }
 
-static void decide_subcmd(int argc, char *const *argv, enum subcmds *subcmd)
+// Backward compatibility to aplay(1).
+static bool decide_subcmd(int argc, char *const *argv, enum subcmds *subcmd)
 {
-	static const char *const subcmds[] = {
-		[SUBCMD_TRANSFER] = "transfer",
-		[SUBCMD_LIST] = "list",
-		[SUBCMD_HELP] = "help",
-		[SUBCMD_VERSION] = "version",
-	};
 	static const struct {
 		const char *const name;
 		enum subcmds subcmd;
@@ -98,25 +93,15 @@ static void decide_subcmd(int argc, char *const *argv, enum subcmds *subcmd)
 	char *pos;
 	int i, j;
 
-	if (argc == 1) {
-		*subcmd = SUBCMD_HELP;
-		return;
-	}
-
-	// sub-command system.
-	for (i = 0; i < ARRAY_SIZE(subcmds); ++i) {
-		if (!strcmp(argv[1], subcmds[i])) {
-			*subcmd = i;
-			return;
-		}
-	}
+	if (argc == 1)
+		return false;
 
 	// Original command system. For long options.
 	for (i = 0; i < ARRAY_SIZE(long_opts); ++i) {
 		for (j = 0; j < argc; ++j) {
 			if (!strcmp(long_opts[i].name, argv[j])) {
 				*subcmd = long_opts[i].subcmd;
-				return;
+				return true;
 			}
 		}
 	}
@@ -131,15 +116,16 @@ static void decide_subcmd(int argc, char *const *argv, enum subcmds *subcmd)
 			for (j = 0; j < ARRAY_SIZE(short_opts); ++j) {
 				if (*pos == short_opts[j].c) {
 					*subcmd = short_opts[j].subcmd;
-					return;
+					return true;
 				}
 			}
 		}
 	}
 
-	*subcmd = SUBCMD_TRANSFER;
+	return false;
 }
 
+// Backward compatibility to aplay(1).
 static bool decide_direction(int argc, char *const *argv,
 			     snd_pcm_stream_t *direction)
 {
@@ -203,16 +189,78 @@ static bool decide_direction(int argc, char *const *argv,
 	return false;
 }
 
+static bool detect_subcmd(int argc, char *const *argv, enum subcmds *subcmd)
+{
+	static const char *const subcmds[] = {
+		[SUBCMD_TRANSFER] = "transfer",
+		[SUBCMD_LIST] = "list",
+		[SUBCMD_HELP] = "help",
+		[SUBCMD_VERSION] = "version",
+	};
+	int i;
+
+	if (argc < 2)
+		return false;
+
+	for (i = 0; i < ARRAY_SIZE(subcmds); ++i) {
+		if (!strcmp(argv[1], subcmds[i])) {
+			*subcmd = i;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static bool detect_direction(int argc, char *const *argv,
+			     snd_pcm_stream_t *direction)
+{
+	if (argc < 3)
+		return false;
+
+	if (!strcmp(argv[2], "capture")) {
+		*direction = SND_PCM_STREAM_CAPTURE;
+		return true;
+	}
+
+	if (!strcmp(argv[2], "playback")) {
+		*direction = SND_PCM_STREAM_PLAYBACK;
+		return true;
+	}
+
+	return false;
+}
+
 int main(int argc, char *const *argv)
 {
 	snd_pcm_stream_t direction;
 	enum subcmds subcmd;
 	int err = 0;
 
-	if (!decide_direction(argc, argv, &direction))
-		subcmd = SUBCMD_HELP;
-	else
-		decide_subcmd(argc, argv, &subcmd);
+	// For compatibility to aplay(1) implementation.
+	if (strstr(argv[0], "arecord") == argv[0] + strlen(argv[0]) - 7 ||
+	    strstr(argv[0], "aplay") == argv[0] + strlen(argv[0]) - 5) {
+		if (!decide_direction(argc, argv, &direction))
+			direction = SND_PCM_STREAM_PLAYBACK;
+		if (!decide_subcmd(argc, argv, &subcmd))
+			subcmd = SUBCMD_TRANSFER;
+	} else {
+		// The first option should be one of subcommands.
+		if (!detect_subcmd(argc, argv, &subcmd))
+			subcmd = SUBCMD_HELP;
+		// The second option should be either 'capture' or 'direction'
+		// if subcommand is neither 'version' nor 'help'.
+		if (subcmd != SUBCMD_VERSION && subcmd != SUBCMD_HELP) {
+			if (!detect_direction(argc, argv, &direction)) {
+				subcmd = SUBCMD_HELP;
+			} else {
+				// argv[0] is needed for unparsed option to use
+				// getopt_long(3).
+				argc -= 2;
+				argv += 2;
+			}
+		}
+	}
 
 	if (subcmd == SUBCMD_TRANSFER)
 		err = subcmd_transfer(argc, argv, direction);

axfer/subcmd-list.c

@@ -10,6 +10,13 @@
 #include "misc.h"
 
 #include <getopt.h>
+#include <stdbool.h>
+
+enum list_op {
+	LIST_OP_DEVICE = 0,
+	LIST_OP_PCM,
+	LIST_OP_HELP,
+};
 
 static int dump_device(snd_ctl_t *handle, const char *id, const char *name,
 		       snd_pcm_stream_t direction, snd_pcm_info_t *info)
@@ -189,46 +196,72 @@ static void print_help(void)
 	printf("help for list sub-command.\n");
 }
 
-int subcmd_list(int argc, char *const *argv, snd_pcm_stream_t direction)
+// Backward compatibility to aplay(1).
+static bool decide_operation(int argc, char *const *argv, enum list_op *op)
 {
-	static const struct {
-		const char *const category;
-		int (*func)(snd_pcm_stream_t direction);
-	} ops[] = {
-		{"device",	list_devices},
-		{"pcm",		list_pcms},
-	};
-	int i;
 	static const char *s_opts = "hlL";
 	static const struct option l_opts[] = {
 		{"list-devices",	0, NULL, 'l'},
 		{"list-pcms",		0, NULL, 'L'},
 		{NULL,			0, NULL, 0}
 	};
-	int c;
-
-	// Renewed command system.
-	if (argc > 2 && !strcmp(argv[1], "list")) {
-		for (i = 0; i < ARRAY_SIZE(ops); ++i) {
-			if (!strcmp(ops[i].category, argv[2]))
-				return ops[i].func(direction);
-		}
-	}
 
-	// Original command system.
 	optind = 0;
 	opterr = 0;
 	while (1) {
-		c = getopt_long(argc, argv, s_opts, l_opts, NULL);
+		int c = getopt_long(argc, argv, s_opts, l_opts, NULL);
 		if (c < 0)
 			break;
-		if (c == 'l')
-			return list_devices(direction);
-		if (c == 'L')
-			return list_pcms(direction);
+		if (c == 'l') {
+			*op = LIST_OP_DEVICE;
+			return true;
+		}
+		if (c == 'L') {
+			*op = LIST_OP_PCM;
+			return true;
+		}
 	}
 
-	print_help();
+	return false;
+}
 
-	return 0;
+static int detect_operation(int argc, char *const *argv, enum list_op *op)
+{
+	static const char *const ops[] = {
+		[LIST_OP_DEVICE] = "device",
+		[LIST_OP_PCM] = "pcm",
+	};
+	int i;
+
+	if (argc < 2)
+		return false;
+
+	for (i = 0; i < ARRAY_SIZE(ops); ++i) {
+		if (!strcmp(argv[1], ops[i])) {
+			*op = i;
+			return true;
+		}
+	}
+
+	return false;
+}
+
+int subcmd_list(int argc, char *const *argv, snd_pcm_stream_t direction)
+{
+	enum list_op op = LIST_OP_HELP;
+	int err = 0;
+
+	// Renewed command system.
+	if (!detect_operation(argc, argv, &op) &&
+	    !decide_operation(argc, argv, &op))
+			err = -EINVAL;
+
+	if (op == LIST_OP_DEVICE)
+		err = list_devices(direction);
+	else if (op == LIST_OP_PCM)
+		err = list_pcms(direction);
+	else
+		print_help();
+
+	return err;
 }

axfer/subcmd-transfer.c

@@ -435,13 +435,6 @@ int subcmd_transfer(int argc, char *const *argv, snd_pcm_stream_t direction)
 	uint64_t actual_frame_count = 0;
 	int err = 0;
 
-	// Renewed command system.
-	if (argc > 2 && !strcmp(argv[1], "transfer")) {
-		// Go ahead to parse file paths properly.
-		--argc;
-		++argv;
-	}
-
 	err = prepare_signal_handler(&ctx);
 	if (err < 0)
 		return err;