From feb8c9be78474599f85f37ae733e564a4bda4e06 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Tue, 26 Jul 2022 04:33:19 +0300 Subject: libcamera: yaml_parser: Replace ok flag to get() with std::optional The YamlObject::get() function takes a default value and an optional bool ok flag to handle parsing errors. This ad-hoc mechanism complicates error handling in callers. A better API is possible by dropping the default value and ok flag and returning an std::optional. Not only does it simplify the calls, it also lets callers handle errors through the standard std::optional class instead of the current ad-hoc mechanism. Provide a get() wrapper around std::optional::value_or() to further simplify callers that don't need any specific error handling. Signed-off-by: Laurent Pinchart Reviewed-by: Naushir Patuck Tested-by: Naushir Patuck Reviewed-by: Jacopo Mondi --- src/libcamera/yaml_parser.cpp | 138 ++++++++++++++++-------------------------- 1 file changed, 53 insertions(+), 85 deletions(-) (limited to 'src') diff --git a/src/libcamera/yaml_parser.cpp b/src/libcamera/yaml_parser.cpp index 5c45e44e..4299f5ab 100644 --- a/src/libcamera/yaml_parser.cpp +++ b/src/libcamera/yaml_parser.cpp @@ -31,12 +31,6 @@ namespace { /* Empty static YamlObject as a safe result for invalid operations */ static const YamlObject empty; -void setOk(bool *ok, bool result) -{ - if (ok) - *ok = result; -} - } /* namespace */ /** @@ -100,54 +94,52 @@ std::size_t YamlObject::size() const } /** - * \fn template YamlObject::get( - * const T &defaultValue, bool *ok) const + * \fn template YamlObject::get() const * \brief Parse the YamlObject as a \a T value - * \param[in] defaultValue The default value when failing to parse - * \param[out] ok The result of whether the parse succeeded * * This function parses the value of the YamlObject as a \a T object, and * returns the value. If parsing fails (usually because the YamlObject doesn't - * store a \a T value), the \a defaultValue is returned, and \a ok is set to - * false. Otherwise, the YamlObject value is returned, and \a ok is set to true. + * store a \a T value), std::nullopt is returned. + * + * \return The YamlObject value, or std::nullopt if parsing failed + */ + +/** + * \fn template YamlObject::get(const T &defaultValue) const + * \brief Parse the YamlObject as a \a T value + * \param[in] defaultValue The default value when failing to parse * - * The \a ok pointer is optional and can be a nullptr if the caller doesn't - * need to know if parsing succeeded. + * This function parses the value of the YamlObject as a \a T object, and + * returns the value. If parsing fails (usually because the YamlObject doesn't + * store a \a T value), the \a defaultValue is returned. * - * \return Value as a bool type + * \return The YamlObject value, or \a defaultValue if parsing failed */ #ifndef __DOXYGEN__ template<> -bool YamlObject::get(const bool &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; - if (value_ == "true") { - setOk(ok, true); + if (value_ == "true") return true; - } else if (value_ == "false") { - setOk(ok, true); + else if (value_ == "false") return false; - } - return defaultValue; + return {}; } template<> -int16_t YamlObject::get(const int16_t &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; if (value_ == "") - return defaultValue; + return {}; char *end; @@ -157,22 +149,19 @@ int16_t YamlObject::get(const int16_t &defaultValue, bool *ok) const if ('\0' != *end || errno == ERANGE || value < std::numeric_limits::min() || value > std::numeric_limits::max()) - return defaultValue; + return {}; - setOk(ok, true); return value; } template<> -uint16_t YamlObject::get(const uint16_t &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; if (value_ == "") - return defaultValue; + return {}; /* * libyaml parses all scalar values as strings. When a string has @@ -183,7 +172,7 @@ uint16_t YamlObject::get(const uint16_t &defaultValue, bool *ok) const */ std::size_t found = value_.find_first_not_of(" \t"); if (found != std::string::npos && value_[found] == '-') - return defaultValue; + return {}; char *end; @@ -193,22 +182,19 @@ uint16_t YamlObject::get(const uint16_t &defaultValue, bool *ok) const if ('\0' != *end || errno == ERANGE || value < std::numeric_limits::min() || value > std::numeric_limits::max()) - return defaultValue; + return {}; - setOk(ok, true); return value; } template<> -int32_t YamlObject::get(const int32_t &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; if (value_ == "") - return defaultValue; + return {}; char *end; @@ -218,22 +204,19 @@ int32_t YamlObject::get(const int32_t &defaultValue, bool *ok) const if ('\0' != *end || errno == ERANGE || value < std::numeric_limits::min() || value > std::numeric_limits::max()) - return defaultValue; + return {}; - setOk(ok, true); return value; } template<> -uint32_t YamlObject::get(const uint32_t &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; if (value_ == "") - return defaultValue; + return {}; /* * libyaml parses all scalar values as strings. When a string has @@ -244,7 +227,7 @@ uint32_t YamlObject::get(const uint32_t &defaultValue, bool *ok) const */ std::size_t found = value_.find_first_not_of(" \t"); if (found != std::string::npos && value_[found] == '-') - return defaultValue; + return {}; char *end; @@ -254,22 +237,19 @@ uint32_t YamlObject::get(const uint32_t &defaultValue, bool *ok) const if ('\0' != *end || errno == ERANGE || value < std::numeric_limits::min() || value > std::numeric_limits::max()) - return defaultValue; + return {}; - setOk(ok, true); return value; } template<> -double YamlObject::get(const double &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; if (value_ == "") - return defaultValue; + return {}; char *end; @@ -277,50 +257,38 @@ double YamlObject::get(const double &defaultValue, bool *ok) const double value = std::strtod(value_.c_str(), &end); if ('\0' != *end || errno == ERANGE) - return defaultValue; + return {}; - setOk(ok, true); return value; } template<> -std::string YamlObject::get(const std::string &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::Value) - return defaultValue; + return {}; - setOk(ok, true); return value_; } template<> -Size YamlObject::get(const Size &defaultValue, bool *ok) const +std::optional YamlObject::get() const { - setOk(ok, false); - if (type_ != Type::List) - return defaultValue; + return {}; if (list_.size() != 2) - return defaultValue; + return {}; - /* - * Add a local variable to validate each dimension in case - * that ok == nullptr. - */ - bool valid; - uint32_t width = list_[0]->get(0, &valid); - if (!valid) - return defaultValue; + auto width = list_[0]->get(); + if (!width) + return {}; - uint32_t height = list_[1]->get(0, &valid); - if (!valid) - return defaultValue; + auto height = list_[1]->get(); + if (!height) + return {}; - setOk(ok, true); - return Size(width, height); + return Size(*width, *height); } #endif /* __DOXYGEN__ */ -- cgit v1.2.1