[libcamera-devel] [PATCH 2/2] libcamera: utils: Provide strchrnul() wrapper

[Jacopo Mondi]

The strchrnul function is a GNU-specific extension to string.h and it's
not availalable on all C libraries (in example, Android's Bionic).

Provide an implementation of the function based around the generally
available strchr() function and use it in the Logger class.

Open code the same wrapper in the application's option parser, where we
cannot use the internal utils namespace.

Signed-off-by: Jacopo Mondi <jacopo at jmondi.org>
---
 include/libcamera/base/utils.h |  1 +
 src/apps/common/options.cpp    |  5 ++++-
 src/libcamera/base/log.cpp     |  2 +-
 src/libcamera/base/utils.cpp   | 19 +++++++++++++++++++
 4 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/include/libcamera/base/utils.h b/include/libcamera/base/utils.h
index eb7bcdf4c173..b7064ec6253b 100644
--- a/include/libcamera/base/utils.h
+++ b/include/libcamera/base/utils.h
@@ -36,6 +36,7 @@ namespace libcamera {
 namespace utils {
 
 const char *basename(const char *path);
+const char *strchrnul(const char *s, int c);
 
 char *secure_getenv(const char *name);
 std::string dirname(const std::string &path);
diff --git a/src/apps/common/options.cpp b/src/apps/common/options.cpp
index 4f7e869144c8..1bbbec7fa25c 100644
--- a/src/apps/common/options.cpp
+++ b/src/apps/common/options.cpp
@@ -363,7 +363,10 @@ KeyValueParser::Options KeyValueParser::parse(const char *arguments)
 	Options options;
 
 	for (const char *pair = arguments; *arguments != '\0'; pair = arguments) {
-		const char *comma = strchrnul(arguments, ',');
+		const char *comma = strchr(arguments, ',');
+		if (!comma)
+			comma = &arguments[strlen(arguments)];
+
 		size_t len = comma - pair;
 
 		/* Skip over the comma. */
diff --git a/src/libcamera/base/log.cpp b/src/libcamera/base/log.cpp
index 55fbd7b03438..cc30681fd67f 100644
--- a/src/libcamera/base/log.cpp
+++ b/src/libcamera/base/log.cpp
@@ -629,7 +629,7 @@ void Logger::parseLogLevels()
 		return;
 
 	for (const char *pair = debug; *debug != '\0'; pair = debug) {
-		const char *comma = strchrnul(debug, ',');
+		const char *comma = utils::strchrnul(debug, ',');
 		size_t len = comma - pair;
 
 		/* Skip over the comma. */
diff --git a/src/libcamera/base/utils.cpp b/src/libcamera/base/utils.cpp
index 6a307940448e..f829a8106b76 100644
--- a/src/libcamera/base/utils.cpp
+++ b/src/libcamera/base/utils.cpp
@@ -39,6 +39,25 @@ const char *basename(const char *path)
 	return base ? base + 1 : path;
 }
 
+/**
+ * \brief Implement strchnul wrapper
+ * \param[in] s The string to seach on
+ * \param[in] c The character to search
+ *
+ * The strchrnul function is a GNU-specific extension to string.h and it's not
+ * available on all C libraries (in example, Android's Bionic). This
+ * implementation realizes strchrnul() on strchr() which is instead more
+ * generally available.
+ *
+ * \return A pointer to the first occurrence of \a c in \a s, or a pointer to
+ * the null byte at the end of \a s if \a c is not found
+ */
+const char *strchrnul(const char *s, int c)
+{
+	const char *p = strchr(s, c);
+	return p ? : s + strlen(s);
+}
+
 /**
  * \brief Get an environment variable
  * \param[in] name The name of the variable to return
-- 
2.38.1