Move link parsing from main.c to media.c, making it part of libmediactl

This makes it possible to benefit from the link parsing code anywhere the
library is being used.

dprintf macro will later be replaced with proper debug support.

Also fix a case where -1 was returned on error and the user was expected to
check the value of errno. Negative error codes are now returned
consistently.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 152 insertions, 15 deletions

diff --git a/src/mediactl.c b/src/mediactl.c
index 8f7d0a9..7c3adbe 100644
--- a/src/mediactl.c
+++ b/src/mediactl.c
@@ -36,6 +36,12 @@
 #include "mediactl.h"
 #include "tools.h"
 
+#ifdef DEBUG
+#define dprintf(...) printf(__VA_ARGS__)
+#else
+#define dprintf(...)
+#endif
+
 struct media_pad *media_entity_remote_source(struct media_pad *pad)
 {
 	unsigned int i;
@@ -107,8 +113,8 @@ int media_setup_link(struct media_device *media,
 	}
 
 	if (i == source->entity->num_links) {
-		printf("%s: Link not found\n", __func__);
-		return -EINVAL;
+		dprintf("%s: Link not found\n", __func__);
+		return -ENOENT;
 	}
 
 	/* source pad */
@@ -124,10 +130,10 @@ int media_setup_link(struct media_device *media,
 	ulink.flags = flags | (link->flags & MEDIA_LNK_FL_IMMUTABLE);
 
 	ret = ioctl(media->fd, MEDIA_IOC_SETUP_LINK, &ulink);
-	if (ret < 0) {
-		printf("%s: Unable to setup link (%s)\n", __func__,
+	if (ret == -1) {
+		dprintf("%s: Unable to setup link (%s)\n", __func__,
 			strerror(errno));
-		return ret;
+		return -errno;
 	}
 
 	link->flags = ulink.flags;
@@ -196,7 +202,7 @@ static int media_enum_links(struct media_device *media)
 		links.links = malloc(entity->info.links * sizeof(struct media_link_desc));
 
 		if (ioctl(media->fd, MEDIA_IOC_ENUM_LINKS, &links) < 0) {
-			printf("%s: Unable to enumerate pads and links (%s).\n",
+			dprintf("%s: Unable to enumerate pads and links (%s).\n",
 				__func__, strerror(errno));
 			free(links.pads);
 			free(links.links);
@@ -220,7 +226,7 @@ static int media_enum_links(struct media_device *media)
 			sink = media_get_entity_by_id(media, link->sink.entity);
 
 			if (source == NULL || sink == NULL) {
-				printf("WARNING entity %u link %u from %u/%u to %u/%u is invalid!\n",
+				dprintf("WARNING entity %u link %u from %u/%u to %u/%u is invalid!\n",
 					id, i, link->source.entity, link->source.index,
 					link->sink.entity, link->sink.index);
 				ret = -EINVAL;
@@ -412,39 +418,40 @@ struct media_device *media_open(const char *name, int verbose)
 
 	media = calloc(1, sizeof(*media));
 	if (media == NULL) {
-		printf("%s: unable to allocate memory\n", __func__);
+		dprintf("%s: unable to allocate memory\n", __func__);
 		return NULL;
 	}
 
 	if (verbose)
-		printf("Opening media device %s\n", name);
+		dprintf("Opening media device %s\n", name);
+
 	media->fd = open(name, O_RDWR);
 	if (media->fd < 0) {
 		media_close(media);
-		printf("%s: Can't open media device %s\n", __func__, name);
+		dprintf("%s: Can't open media device %s\n", __func__, name);
 		return NULL;
 	}
 
 	if (verbose)
-		printf("Enumerating entities\n");
+		dprintf("Enumerating entities\n");
 
 	ret = media_enum_entities(media, verbose);
 
 	if (ret < 0) {
-		printf("%s: Unable to enumerate entities for device %s (%s)\n",
+		dprintf("%s: Unable to enumerate entities for device %s (%s)\n",
 			__func__, name, strerror(-ret));
 		media_close(media);
 		return NULL;
 	}
 
 	if (verbose) {
-		printf("Found %u entities\n", media->entities_count);
-		printf("Enumerating pads and links\n");
+		dprintf("Found %u entities\n", media->entities_count);
+		dprintf("Enumerating pads and links\n");
 	}
 
 	ret = media_enum_links(media);
 	if (ret < 0) {
-		printf("%s: Unable to enumerate pads and linksfor device %s\n",
+		dprintf("%s: Unable to enumerate pads and linksfor device %s\n",
 			__func__, name);
 		media_close(media);
 		return NULL;
@@ -472,3 +479,133 @@ void media_close(struct media_device *media)
 	free(media->entities);
 	free(media);
 }
+
+struct media_pad *media_parse_pad(struct media_device *media,
+				  const char *p, char **endp)
+{
+	unsigned int entity_id, pad;
+	struct media_entity *entity;
+	char *end;
+
+	for (; isspace(*p); ++p);
+
+	if (*p == '"') {
+		for (end = (char *)p + 1; *end && *end != '"'; ++end);
+		if (*end != '"')
+			return NULL;
+
+		entity = media_get_entity_by_name(media, p + 1, end - p - 1);
+		if (entity == NULL)
+			return NULL;
+
+		++end;
+	} else {
+		entity_id = strtoul(p, &end, 10);
+		entity = media_get_entity_by_id(media, entity_id);
+		if (entity == NULL)
+			return NULL;
+	}
+	for (; isspace(*end); ++end);
+
+	if (*end != ':')
+		return NULL;
+	for (p = end + 1; isspace(*p); ++p);
+
+	pad = strtoul(p, &end, 10);
+	for (p = end; isspace(*p); ++p);
+
+	if (pad >= entity->info.pads)
+		return NULL;
+
+	for (p = end; isspace(*p); ++p);
+	if (endp)
+		*endp = (char *)p;
+
+	return &entity->pads[pad];
+}
+
+struct media_link *media_parse_link(struct media_device *media,
+				    const char *p, char **endp)
+{
+	struct media_link *link;
+	struct media_pad *source;
+	struct media_pad *sink;
+	unsigned int i;
+	char *end;
+
+	source = media_parse_pad(media, p, &end);
+	if (source == NULL)
+		return NULL;
+
+	if (end[0] != '-' || end[1] != '>')
+		return NULL;
+	p = end + 2;
+
+	sink = media_parse_pad(media, p, &end);
+	if (sink == NULL)
+		return NULL;
+
+	*endp = end;
+
+	for (i = 0; i < source->entity->num_links; i++) {
+		link = &source->entity->links[i];
+
+		if (link->source == source && link->sink == sink)
+			return link;
+	}
+
+	return NULL;
+}
+
+int media_parse_setup_link(struct media_device *media,
+			   const char *p, char **endp)
+{
+	struct media_link *link;
+	__u32 flags;
+	char *end;
+
+	link = media_parse_link(media, p, &end);
+	if (link == NULL) {
+		dprintf("Unable to parse link\n");
+		return -EINVAL;
+	}
+
+	p = end;
+	if (*p++ != '[') {
+		dprintf("Unable to parse link flags\n");
+		return -EINVAL;
+	}
+
+	flags = strtoul(p, &end, 10);
+	for (p = end; isspace(*p); p++);
+	if (*p++ != ']') {
+		dprintf("Unable to parse link flags\n");
+		return -EINVAL;
+	}
+
+	for (; isspace(*p); p++);
+	*endp = (char *)p;
+
+	dprintf("Setting up link %u:%u -> %u:%u [%u]\n",
+		link->source->entity->info.id, link->source->index,
+		link->sink->entity->info.id, link->sink->index,
+		flags);
+
+	return media_setup_link(media, link->source, link->sink, flags);
+}
+
+int media_parse_setup_links(struct media_device *media, const char *p)
+{
+	char *end;
+	int ret;
+
+	do {
+		ret = media_parse_setup_link(media, p, &end);
+		if (ret < 0)
+			return ret;
+
+		p = end + 1;
+	} while (*end == ',');
+
+	return *end ? -EINVAL : 0;
+}