From 16063986bbc1f7c1656df3bf5d369e275398a483 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Wed, 15 Oct 2025 17:21:56 +0300 Subject: [PATCH] libcamera: global_configuration: Override options with environment variables MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit libcamera supports several environment variables that can override configuration options. This requires components that use such overrides to call the special envOption() and envListOption() functions, spreading knowledge of the overrides through the code base. This will hinder future enhancements to the global configuration, such as implementing per-camera options that will override pipeline handler-level options. To prepare for that, move handling of the environment variables to the GlobalConfiguration class. Signed-off-by: Laurent Pinchart Reviewed-by: Isaac Scott Reviewed-by: Barnabás Pőcze --- .../libcamera/internal/global_configuration.h | 7 - src/libcamera/camera_manager.cpp | 4 +- src/libcamera/global_configuration.cpp | 180 +++++++++++------- src/libcamera/ipa_manager.cpp | 9 +- src/libcamera/ipa_proxy.cpp | 6 +- src/libcamera/software_isp/software_isp.cpp | 4 +- 6 files changed, 124 insertions(+), 86 deletions(-) diff --git a/include/libcamera/internal/global_configuration.h b/include/libcamera/internal/global_configuration.h index 5eb646e3..0d2ccb8a 100644 --- a/include/libcamera/internal/global_configuration.h +++ b/include/libcamera/internal/global_configuration.h @@ -42,13 +42,6 @@ public: std::optional> listOption( const std::initializer_list confPath) const; - std::optional envOption( - const char *const envVariable, - const std::initializer_list confPath) const; - std::optional> envListOption( - const char *const envVariable, - const std::initializer_list confPath, - const std::string delimiter = ":") const; private: void load(); diff --git a/src/libcamera/camera_manager.cpp b/src/libcamera/camera_manager.cpp index f774bd84..0dd4e0c5 100644 --- a/src/libcamera/camera_manager.cpp +++ b/src/libcamera/camera_manager.cpp @@ -114,9 +114,7 @@ void CameraManager::Private::createPipelineHandlers() * there is no configuration file. */ const auto pipesList = - configuration().envListOption("LIBCAMERA_PIPELINES_MATCH_LIST", - { "pipelines_match_list" }, - ","); + configuration().listOption({ "pipelines_match_list" }); if (pipesList.has_value()) { /* * When a list of preferred pipelines is defined, iterate diff --git a/src/libcamera/global_configuration.cpp b/src/libcamera/global_configuration.cpp index 62b9762d..46a285c3 100644 --- a/src/libcamera/global_configuration.cpp +++ b/src/libcamera/global_configuration.cpp @@ -7,6 +7,7 @@ #include "libcamera/internal/global_configuration.h" +#include #include #include #include @@ -30,6 +31,99 @@ const std::vector globalConfigurationFiles = { std::filesystem::path(LIBCAMERA_DATA_DIR) / "configuration.yaml", }; +class EnvironmentProcessor +{ +public: + virtual ~EnvironmentProcessor() = default; + + virtual void process(ValueNode &node, const char *env) = 0; +}; + +/* A processor that sets a fixed value. */ +template +class EnvironmentFixedProcessor : public EnvironmentProcessor +{ +public: + EnvironmentFixedProcessor(const T &value) + : value_(value) + { + } + + void process(ValueNode &node, [[maybe_unused]] const char *env) override + { + node.set(value_); + } + +private: + T value_; +}; + +/* + * A processor that parses the environment variable as a list of strings with a + * custom delimiter. + */ +class EnvironmentListProcessor : public EnvironmentProcessor +{ +public: + EnvironmentListProcessor(const char *delimiter) + : delimiter_(delimiter) + { + } + + void process(ValueNode &node, const char *env) override + { + for (auto &&value : utils::split(env, delimiter_)) + node.add(std::make_unique(std::move(value))); + } + +private: + const std::string delimiter_; +}; + +/* A processor that copies the value of the environment variable. */ +class EnvironmentValueProcessor : public EnvironmentProcessor +{ +public: + void process(ValueNode &node, const char *env) override + { + node.set(std::string{ env }); + } +}; + +struct EnvironmentOverride { + const char *variable; + std::initializer_list path; + std::unique_ptr processor; +}; + +const std::array environmentOverrides{ { + { + "LIBCAMERA_IPA_CONFIG_PATH", + { "ipa", "config_paths" }, + std::make_unique(":"), + }, { + "LIBCAMERA_IPA_FORCE_ISOLATION", + { "ipa", "force_isolation" }, + std::make_unique>(true), + }, { + "LIBCAMERA_IPA_MODULE_PATH", + { "ipa", "module_paths" }, + std::make_unique(":"), + }, { + "LIBCAMERA_IPA_PROXY_PATH", + { "ipa", "proxy_paths" }, + std::make_unique(":"), + }, { + "LIBCAMERA_PIPELINES_MATCH_LIST", + { "pipelines_match_list" }, + std::make_unique(","), + }, { + "LIBCAMERA_SOFTISP_MODE", + { "software_isp", "mode" }, + std::make_unique(), + }, +} }; + } /* namespace */ LOG_DEFINE_CATEGORY(Configuration) @@ -50,9 +144,9 @@ LOG_DEFINE_CATEGORY(Configuration) * reported and no configuration file is used. This is to prevent libcamera from * using an unintended configuration file. * - * The configuration can be accessed using the provided helpers, namely - * option(), envOption(), listOption() and envListOption() to access individual - * options, or configuration() to access the whole configuration. + * The configuration can be accessed using the provided helpers, namely option() + * and listOption() to access individual options, or configuration() to access + * the whole configuration. */ /** @@ -66,6 +160,25 @@ GlobalConfiguration::GlobalConfiguration() configuration_->add("version", std::make_unique(1)); configuration_->add("configuration", std::make_unique()); } + + /* Process environment variables that override configuration options. */ + ValueNode *cfg = configuration_->at("configuration"); + + for (const EnvironmentOverride &envOverride : environmentOverrides) { + const char *envValue = utils::secure_getenv(envOverride.variable); + if (!envValue || !envValue[0]) + continue; + + std::unique_ptr node = std::make_unique(); + envOverride.processor->process(*node.get(), envValue); + + cfg->erase(envOverride.path); + + if (!cfg->add(envOverride.path, std::move(node))) + LOG(Configuration, Error) + << "Failed to override " + << utils::join(envOverride.path, "/"); + } } void GlobalConfiguration::load() @@ -185,65 +298,4 @@ std::optional> GlobalConfiguration::listOption( return c->get>(); } -/** - * \brief Retrieve the value of environment variable with a fallback on the configuration file - * \param[in] envVariable Environment variable to get the value from - * \param[in] confPath The sequence of YAML section names to fall back on when - * \a envVariable is unavailable - * - * This helper looks first at the given environment variable and if it is - * defined then it returns its value (even if it is empty). Otherwise it looks - * for \a confPath the same way as in GlobalConfiguration::option. Only string - * values are supported. - * - * \note Support for using environment variables to configure libcamera behavior - * is provided here mostly for backward compatibility reasons. Introducing new - * configuration environment variables is discouraged. - * - * \return The value retrieved from the given environment if it is set, - * otherwise the value from the configuration file if it exists, or no value if - * it does not - */ -std::optional GlobalConfiguration::envOption( - const char *envVariable, - const std::initializer_list confPath) const -{ - const char *envValue = utils::secure_getenv(envVariable); - if (envValue) - return std::optional{ std::string{ envValue } }; - return option(confPath); -} - -/** - * \brief Retrieve the value of the configuration option from a file or environment - * \param[in] envVariable Environment variable to get the value from - * \param[in] confPath The same as in GlobalConfiguration::option - * \param[in] delimiter Items separator in the environment variable - * - * This helper looks first at the given environment variable and if it is - * defined (even if it is empty) then it splits its value by semicolons and - * returns the resulting list of strings. Otherwise it looks for \a confPath the - * same way as in GlobalConfiguration::option, value of which must be a list of - * strings. - * - * \note Support for using environment variables to configure libcamera behavior - * is provided here mostly for backward compatibility reasons. Introducing new - * configuration environment variables is discouraged. - * - * \return A vector of strings retrieved from the given environment option or - * configuration file or no value if not found; the vector may be empty - */ -std::optional> GlobalConfiguration::envListOption( - const char *const envVariable, - const std::initializer_list confPath, - const std::string delimiter) const -{ - const char *envValue = utils::secure_getenv(envVariable); - if (envValue) { - auto items = utils::split(envValue, delimiter); - return std::vector(items.begin(), items.end()); - } - return listOption(confPath); -} - } /* namespace libcamera */ diff --git a/src/libcamera/ipa_manager.cpp b/src/libcamera/ipa_manager.cpp index dd1f483b..a351f4f7 100644 --- a/src/libcamera/ipa_manager.cpp +++ b/src/libcamera/ipa_manager.cpp @@ -114,18 +114,15 @@ IPAManager::IPAManager(const CameraManager &cm) if (!pubKey_.isValid()) LOG(IPAManager, Warning) << "Public key not valid"; - char *force = utils::secure_getenv("LIBCAMERA_IPA_FORCE_ISOLATION"); - forceIsolation_ = (force && force[0] != '\0') || - (!force && configuration.option({ "ipa", "force_isolation" }) - .value_or(false)); + forceIsolation_ = configuration.option({ "ipa", "force_isolation" }) + .value_or(false); #endif unsigned int ipaCount = 0; /* User-specified paths take precedence. */ const auto modulePaths = - configuration.envListOption( - "LIBCAMERA_IPA_MODULE_PATH", { "ipa", "module_paths" }) + configuration.listOption({ "ipa", "module_paths" }) .value_or(std::vector()); for (const auto &dir : modulePaths) { if (dir.empty()) diff --git a/src/libcamera/ipa_proxy.cpp b/src/libcamera/ipa_proxy.cpp index 6c8780a0..bc8ff090 100644 --- a/src/libcamera/ipa_proxy.cpp +++ b/src/libcamera/ipa_proxy.cpp @@ -124,11 +124,9 @@ IPAProxy::IPAProxy(IPAModule *ipam, const CameraManager &cm) { const GlobalConfiguration &configuration = cm._d()->configuration(); - configPaths_ = configuration.envListOption("LIBCAMERA_IPA_CONFIG_PATH", - { "ipa", "config_paths" }) + configPaths_ = configuration.listOption({ "ipa", "config_paths" }) .value_or(std::vector()); - execPaths_ = configuration.envListOption("LIBCAMERA_IPA_PROXY_PATH", - { "ipa", "proxy_paths" }) + execPaths_ = configuration.listOption({ "ipa", "proxy_paths" }) .value_or(std::vector()); } diff --git a/src/libcamera/software_isp/software_isp.cpp b/src/libcamera/software_isp/software_isp.cpp index cd0e9d06..d227bd8e 100644 --- a/src/libcamera/software_isp/software_isp.cpp +++ b/src/libcamera/software_isp/software_isp.cpp @@ -106,11 +106,11 @@ SoftwareIsp::SoftwareIsp(PipelineHandler *pipe, const CameraSensor *sensor, #if HAVE_DEBAYER_EGL const GlobalConfiguration &configuration = cm._d()->configuration(); - std::optional softISPMode = configuration.envOption("LIBCAMERA_SOFTISP_MODE", { "software_isp", "mode" }); + std::optional softISPMode = configuration.option({ "software_isp", "mode" }); if (softISPMode) { if (softISPMode != "gpu" && softISPMode != "cpu") { LOG(SoftwareIsp, Error) - << "Invalid LIBCAMERA_SOFTISP_MODE \"" + << "Invalid software ISP mode \"" << softISPMode.value() << "\", must be \"cpu\" or \"gpu\""; return;