[PATCH v2 06/13] 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 | 24 ++++++++++++++++++-
 src/libcamera/base/global_configuration.cpp   | 17 ++++---------
 src/libcamera/base/log.cpp                    |  2 ++
 3 files changed, 30 insertions(+), 13 deletions(-)

diff --git a/include/libcamera/internal/global_configuration.h b/include/libcamera/internal/global_configuration.h
index 6c49f8e7..a8a965dd 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 +24,27 @@ public:
 
 	static unsigned int version();
 	static Configuration configuration();
-	static std::optional<std::string> option(const char *const 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 char *const confPath)
+	{
+		YamlObject *c = &const_cast<YamlObject &>(configuration());
+		for (auto part : utils::details::StringSplitter(confPath, "."))
+			c = &const_cast<YamlObject &>((*c)[part]);
+		return c->get<T>();
+	}
+
 	static std::optional<std::string> envOption(const char *const envVariable,
 						    const char *const confPath);
 
diff --git a/src/libcamera/base/global_configuration.cpp b/src/libcamera/base/global_configuration.cpp
index f72ca352..03d0369b 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"
 
@@ -146,20 +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 char *const confPath)
-{
-	YamlObject *c = &const_cast<YamlObject &>(configuration());
-	for (auto part : utils::details::StringSplitter(confPath, "."))
-		c = &const_cast<YamlObject &>((*c)[part]);
-	return c->get<std::string>();
-}
 
 /**
  * \brief Return value of the configuration option from a file or environment
@@ -185,7 +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 ff6be340..d4421a36 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();
-- 
2.42.0