[v4l-utils PATCH 1/1] v4l: libv4l2subdev: Drop length argument from string conversion functions

[Sakari Ailus <sakari.ailus@linux.intel.com>]

v4l2_subdev_string_to_pixelcode() and v4l2_subdev_string_to_field() take a
string and the length of that string as an argument. This has been
motivated by existing usage in the same library. While this works for the
library quite well, it's not a great API.

Instead, drop the length argument and pass a nul terminated string to the
string conversion functions.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
This goes on top of the media bus code patchset.

 utils/media-ctl/libv4l2subdev.c | 36 ++++++++++++++++++++++--------------
 utils/media-ctl/v4l2subdev.h    | 12 ++++--------
 2 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/utils/media-ctl/libv4l2subdev.c b/utils/media-ctl/libv4l2subdev.c
index 408f1cf..70e1e39 100644
--- a/utils/media-ctl/libv4l2subdev.c
+++ b/utils/media-ctl/libv4l2subdev.c
@@ -308,6 +308,7 @@ static int v4l2_subdev_parse_format(struct media_device *media,
 {
 	enum v4l2_mbus_pixelcode code;
 	unsigned int width, height;
+	char *fmt;
 	char *end;
 
 	/*
@@ -318,7 +319,12 @@ static int v4l2_subdev_parse_format(struct media_device *media,
 	for (end = (char *)p;
 	     *end != '/' && *end != ' ' && *end != '\0'; ++end);
 
-	code = v4l2_subdev_string_to_pixelcode(p, end - p);
+	fmt = strndup(p, end - p);
+	if (!fmt)
+		return -ENOMEM;
+
+	code = v4l2_subdev_string_to_pixelcode(fmt);
+	free(fmt);
 	if (code == (enum v4l2_mbus_pixelcode)-1) {
 		media_dbg(media, "Invalid pixel code '%.*s'\n", end - p, p);
 		return -EINVAL;
@@ -475,11 +481,19 @@ static struct media_pad *v4l2_subdev_parse_pad_format(
 
 		if (strhazit("field:", &p)) {
 			enum v4l2_field field;
+			char *strfield;
 
 			for (end = (char *)p; isalpha(*end) || *end == '-';
 			     ++end);
 
-			field = v4l2_subdev_string_to_field(p, end - p);
+			strfield = strndup(p, end - p);
+			if (!strfield) {
+				*endp = (char *)p;
+				return NULL;
+			}
+
+			field = v4l2_subdev_string_to_field(strfield);
+			free(strfield);
 			if (field == (enum v4l2_field)-1) {
 				media_dbg(media, "Invalid field value '%*s'\n",
 					  end - p, p);
@@ -770,14 +784,12 @@ const char *v4l2_subdev_pixelcode_to_string(enum v4l2_mbus_pixelcode code)
 	return "unknown";
 }
 
-enum v4l2_mbus_pixelcode v4l2_subdev_string_to_pixelcode(const char *string,
-							 unsigned int length)
+enum v4l2_mbus_pixelcode v4l2_subdev_string_to_pixelcode(const char *string)
 {
 	unsigned int i;
 
 	for (i = 0; i < ARRAY_SIZE(mbus_formats); ++i) {
-		if (strncmp(mbus_formats[i].name, string, length) == 0
-		    && mbus_formats[i].name[length] == '\0')
+		if (strcmp(mbus_formats[i].name, string) == 0)
 			return mbus_formats[i].code;
 	}
 
@@ -812,20 +824,16 @@ const char *v4l2_subdev_field_to_string(enum v4l2_field field)
 	return "unknown";
 }
 
-enum v4l2_field v4l2_subdev_string_to_field(const char *string,
-					    unsigned int length)
+enum v4l2_field v4l2_subdev_string_to_field(const char *string)
 {
 	unsigned int i;
 
 	for (i = 0; i < ARRAY_SIZE(fields); ++i) {
-		if (strncasecmp(fields[i].name, string, length) == 0)
-			break;
+		if (strcasecmp(fields[i].name, string) == 0)
+			return fields[i].field;
 	}
 
-	if (i == ARRAY_SIZE(fields))
-		return (enum v4l2_field)-1;
-
-	return fields[i].field;
+	return (enum v4l2_field)-1;
 }
 
 const enum v4l2_mbus_pixelcode *v4l2_subdev_pixelcode_list(void)
diff --git a/utils/media-ctl/v4l2subdev.h b/utils/media-ctl/v4l2subdev.h
index 33327d6..dcdb35c 100644
--- a/utils/media-ctl/v4l2subdev.h
+++ b/utils/media-ctl/v4l2subdev.h
@@ -247,15 +247,13 @@ const char *v4l2_subdev_pixelcode_to_string(enum v4l2_mbus_pixelcode code);
 
 /**
  * @brief Parse string to media bus pixel code.
- * @param string - input string
- * @param length - length of the string
+ * @param string - nul terminalted string, textual media bus pixel code
  *
  * Parse human readable string @a string to an media bus pixel code.
  *
  * @return media bus pixelcode on success, -1 on failure.
  */
-enum v4l2_mbus_pixelcode v4l2_subdev_string_to_pixelcode(const char *string,
-							 unsigned int length);
+enum v4l2_mbus_pixelcode v4l2_subdev_string_to_pixelcode(const char *string);
 
 /**
  * @brief Convert a field order to string.
@@ -269,15 +267,13 @@ const char *v4l2_subdev_field_to_string(enum v4l2_field field);
 
 /**
  * @brief Parse string to field order.
- * @param string - input string
- * @param length - length of the string
+ * @param string - nul terminated string, textual media bus pixel code
  *
  * Parse human readable string @a string to field order.
  *
  * @return field order on success, -1 on failure.
  */
-enum v4l2_field v4l2_subdev_string_to_field(const char *string,
-					    unsigned int length);
+enum v4l2_field v4l2_subdev_string_to_field(const char *string);
 
 /**
  * @brief Enumerate library supported media bus pixel codes.
-- 
2.1.0.231.g7484e3b