[PATCH v3 06/14] config: Look up log color configuration in configuration file

[Milan Zamazal]

The configuration snippet:

  configuration:
    log:
      color: BOOL

In order to use the global configuration access helper for a boolean
value, we must make a template from it.  To make the template visible,
we must implement it in the header file, otherwise undefined reference
error would be reported when linking.

We don't implement envOption helper for boolean here, because we would
have to deal with a specific value interpretation in this particular
case.

Signed-off-by: Milan Zamazal <mzamazal at redhat.com>
---
 .../libcamera/internal/global_configuration.h | 27 ++++++++++++++++++-
 src/libcamera/base/global_configuration.cpp   | 20 ++++----------
 src/libcamera/base/log.cpp                    |  2 ++
 3 files changed, 33 insertions(+), 16 deletions(-)

diff --git a/include/libcamera/internal/global_configuration.h b/include/libcamera/internal/global_configuration.h
index 7c39c969..42c60417 100644
--- a/include/libcamera/internal/global_configuration.h
+++ b/include/libcamera/internal/global_configuration.h
@@ -11,6 +11,8 @@
 #include <optional>
 #include <vector>
 
+#include <libcamera/base/utils.h>
+
 #include "libcamera/internal/yaml_parser.h"
 
 namespace libcamera {
@@ -22,7 +24,30 @@ public:
 
 	static unsigned int version();
 	static Configuration configuration();
-	static std::optional<std::string> option(const std::string &confPath);
+
+	template<typename T,
+		 std::enable_if_t<
+			 std::is_same_v<bool, T> ||
+			 std::is_same_v<double, T> ||
+			 std::is_same_v<int8_t, T> ||
+			 std::is_same_v<uint8_t, T> ||
+			 std::is_same_v<int16_t, T> ||
+			 std::is_same_v<uint16_t, T> ||
+			 std::is_same_v<int32_t, T> ||
+			 std::is_same_v<uint32_t, T> ||
+			 std::is_same_v<std::string, T> ||
+			 std::is_same_v<Size, T>> * = nullptr>
+	static std::optional<T> option(const std::string &confPath)
+	{
+		YamlObject *c = &const_cast<YamlObject &>(configuration());
+		for (auto part : utils::details::StringSplitter(confPath, "."))
+			if (c->contains(part))
+				c = &const_cast<YamlObject &>((*c)[part]);
+			else
+				return std::optional<T>();
+		return c->get<T>();
+	}
+
 	static std::optional<std::string> envOption(const char *const envVariable,
 						    const std::string &confPath);
 
diff --git a/src/libcamera/base/global_configuration.cpp b/src/libcamera/base/global_configuration.cpp
index b64bf28e..f18ca28b 100644
--- a/src/libcamera/base/global_configuration.cpp
+++ b/src/libcamera/base/global_configuration.cpp
@@ -15,7 +15,6 @@
 
 #include <libcamera/base/file.h>
 #include <libcamera/base/log.h>
-#include <libcamera/base/utils.h>
 
 #include "libcamera/internal/yaml_parser.h"
 
@@ -146,23 +145,14 @@ GlobalConfiguration::Configuration GlobalConfiguration::get()
 }
 
 /**
+ * \fn static std::optional<T> GlobalConfiguration::option(const char *const confPath)
  * \brief Return value of the configuration option identified by \a confPath
+ * \tparam T The type of the retrieved configuration value
  * \param[in] confPath Sequence of the YAML section names (excluding
  * `configuration') leading to the requested option separated by dots
- * \return A value if an item corresponding to \a confPath exists in the
- * configuration file, no value otherwise
+ * \return A value of type \a T if an item corresponding to \a confPath exists
+ * in the configuration file and matches type \a T, no value otherwise
  */
-std::optional<std::string> GlobalConfiguration::option(
-	const std::string &confPath)
-{
-	YamlObject *c = &const_cast<YamlObject &>(configuration());
-	for (auto part : utils::details::StringSplitter(confPath, "."))
-		if (c->contains(part))
-			c = &const_cast<YamlObject &>((*c)[part]);
-		else
-			return std::optional<std::string>();
-	return c->get<std::string>();
-}
 
 /**
  * \brief Return value of the configuration option from a file or environment
@@ -188,7 +178,7 @@ std::optional<std::string> GlobalConfiguration::envOption(
 	const char *envValue = utils::secure_getenv(envVariable);
 	if (envValue)
 		return std::optional{ std::string{ envValue } };
-	return option(confPath);
+	return option<std::string>(confPath);
 }
 
 /**
diff --git a/src/libcamera/base/log.cpp b/src/libcamera/base/log.cpp
index 07352f6c..d522e895 100644
--- a/src/libcamera/base/log.cpp
+++ b/src/libcamera/base/log.cpp
@@ -590,6 +590,8 @@ void Logger::logSetLevel(const char *category, const char *level)
 Logger::Logger()
 {
 	bool color = !utils::secure_getenv("LIBCAMERA_LOG_NO_COLOR");
+	if (color)
+		color = GlobalConfiguration::option<bool>("log.color").value_or(true);
 	logSetStream(&std::cerr, color);
 
 	parseLogFile();
-- 
2.44.1