cmake_pkg_config¶
Added in version 3.31.
Process pkg-config format package files.
Synopsis¶
cmake_pkg_config(EXTRACT <package> [<version>] [...])
Introduction¶
This command generates CMake variables and targets from pkg-config format
package files natively, without needing to invoke or even require the presence
of a pkg-config implementation. A <package> is either an absolute path to a
package file, or a package name to be searched for using the typical pkg-config
search patterns. The optional <version> string has the same format and
semantics as a pkg-config style version specifier, with the exception that if
no comparison operator is specified = is assumed.
There are multiple signatures for this command, and some of the options are common between them. They are:
- EXACT/- QUIET/- REQUIRED
- The - EXACToption requests that the version string be matched exactly (including empty string, if no version is provided), overriding the typical pkg-config version comparison algorithm. This will ignore any comparison operator attached to the version string.- The - QUIEToption disables informational messages, including those indicating that the package cannot be found if it is not- REQUIRED. The- REQUIREDoption stops processing with an error message if the package cannot be found.
- STRICTNESS <mode>
- Specify how strictly the contents of the package files will be verified during parsing and resolution. An invalid file, under the provided strictness mode, will cause the command to fail. Possible modes are: - STRICT: Closely mirrors the behavior of the original FDO pkg-config. Variables and keywords must be unique. Variables must be defined before they are used. The Name, Description, and Version keywords must be present. The overall structure of the file must be valid and parsable.
- PERMISSIVE: Closely mirrors the behavior of the pkgconf implementation. Duplicate variables are overridden. Duplicate keywords are appended. Undefined variables resolve to empty strings. The Name, Description, and Version keywords must be present. The overall structure of the file must be valid and parsable.
- BEST_EFFORT: Same behavior as- PERMISSIVEwith regards to duplicate or uninitialized variables and keywords, but will not fail under any conditions. Package files which require BEST_EFFORT will fail validation under all other major implementations and should be fixed.
 - The default strictness is - PERMISSIVE.
- ENV_MODE
- Specifies which environment variables will be queried when running a given command. Possible modes are: - FDO: Queries only the original set of- PKG_CONFIG_*environment variables used by the freedesktop.org- pkg-configimplementation.
- PKGCONF: Queries the more extensive set of environment variables used by the- pkgconfimplementation.
- IGNORE: Ignores the presence, absence, and value of environment variables entirely. In all cases an environment variable would be queried its treated as defined, but with a value of empty string for the purpose of the operation. This does not modify the current environment. For boolean environment variables, such as- PKG_CONFIG_ALLOW_*, this means they are evaluated as truthy.- PKG_CONFIG_SYSROOT_PATHis a minor exception. When- ENV_MODE IGNOREis used, no root path prepending will occur by default and- pc_sysrootdirremains defaulted to- /.
 - Target-generating subcommands always ignore flag-filtering environment variables. The default environment mode is - PKGCONF.
- PC_LIBDIR <path>...
- Overrides the default search location for package files; also used to derive the - pc_pathpackage variable.- When this option is not provided, the default library directory is the first available of the following values: - CMAKE_PKG_CONFIG_PC_LIB_DIRS
- The - PKG_CONFIG_LIBDIRenvironment variable
- The output of - pkg-config --variable pc_path pkg-config
- A platform-dependent default value 
 
- PC_PATH <path>...
- Overrides the supplemental package file directories which will be prepended to the search path; also used to derive the - pc_pathpackage variable.- When this option is not provided, the default paths are the first available of the following values: - CMAKE_PKG_CONFIG_PC_PATH
- The - PKG_CONFIG_PATHenvironment variable
- Empty list 
 
- DISABLE_UNINSTALLED <bool>
- Overrides the search behavior for "uninstalled" package files. These are package files with an "-uninstalled" suffix which describe packages integrated directly from a build tree. - Normally such package files have higher priority than "installed" packages. When - DISABLE_UNINSTALLEDis true, searching for "uninstalled" packages is disabled.- When this option is not provided, the default search behavior is determined by the first available of the following values: - CMAKE_PKG_CONFIG_DISABLE_UNINSTALLED
- If the - PKG_CONFIG_DISABLE_UNINSTALLEDenvironment variable is defined the search is disabled, otherwise it is enabled.
 
- PC_SYSROOT_DIR <path>
- Overrides the root path which will be prepended to paths specified by - -Icompile flags and- -Llibrary search locations; also used to derive the- pc_sysrootdirpackage variable.- When this option is not provided, the default root path is provided by the first available of the following values: - CMAKE_PKG_CONFIG_SYSROOT_DIR
- The - PKG_CONFIG_SYSROOT_DIRenvironment variable
- If no root path is available, nothing will be prepended to include or library directory paths and - pc_sysrootdirwill be set to- /
 
- TOP_BUILD_DIR <path>
- Overrides the top build directory path used to derived the - pc_top_builddirpackage variable.- When this option is not provided, the default top build directory path is the first available of the following values: - CMAKE_PKG_CONFIG_TOP_BUILD_DIR
- The - PKG_CONFIG_TOP_BUILD_DIRenvironment variable
- If no top build directory path is available, the - pc_top_builddirpackage variable is not set
 
Signatures¶
- cmake_pkg_config(EXTRACT <package> [<version>] [...])¶
- Extract the contents of the package into variables. - cmake_pkg_config(EXTRACT <package> [<version>] [REQUIRED] [EXACT] [QUIET] [STRICTNESS <mode>] [ENV_MODE <mode>] [PC_LIBDIR <path>...] [PC_PATH <path>...] [DISABLE_UNINSTALLED <bool>] [PC_SYSROOT_DIR <path>] [TOP_BUILD_DIR <path>] [SYSTEM_INCLUDE_DIRS <path>...] [SYSTEM_LIBRARY_DIRS <path>...] [ALLOW_SYSTEM_INCLUDES <bool>] [ALLOW_SYSTEM_LIBS <bool>]) 
The following variables will be populated from the contents of package file:
| Variable | Type | Definition | 
|---|---|---|
| 
 | String | Value of the  | 
| 
 | String | Value of the  | 
| 
 | String | Value of the  | 
| 
 | List | Value of the  | 
| 
 | List | Value of the  | 
| 
 | List | Value of the  | 
| 
 | String | Value of the  | 
| 
 | List | All  | 
| 
 | List | All flags not prefixed with  | 
| 
 | String | Value of the  | 
| 
 | List | All  | 
| 
 | List | All  | 
| 
 | List | All flags not prefixed with  | 
| 
 | * | 
 | 
- SYSTEM_INCLUDE_DIRS
- Overrides the "system" directories for the purpose of flag mangling include directories in - CMAKE_PKG_CONFIG_CFLAGSand derived variables.- When this option is not provided, the default directories are provided by the first available of the following values: - CMAKE_PKG_CONFIG_SYS_INCLUDE_DIRS
- The - PKG_CONFIG_SYSTEM_INCLUDE_PATHenvironment variable
- The output of - pkgconf --variable pc_system_includedirs pkg-config
- A platform-dependent default value 
 - Additionally, when the - ENV_MODEis- PKGCONFthe- CMAKE_PKG_CONFIG_PKGCONF_INCLUDESvariable will be concatenated to the list if available. If it is not available, the following environment variables will be queried and concatenated:- CPATH
- C_INCLUDE_PATH
- CPLUS_INCLUDE_PATH
- OBJC_INCLUDE_PATH
- INCLUDE(Windows Only)
 
- SYSTEM_LIBRARY_DIRS
- Overrides the "system" directories for the purpose of flag mangling library directories in - CMAKE_PKG_CONFIG_LIBSand derived variables.- When this option is not provided, the default directories are provided by the first available of the following values: - CMAKE_PKG_CONFIG_SYS_LIB_DIRS
- The - PKG_CONFIG_SYSTEM_LIBRARY_PATHenvironment variable
- The output of - pkgconf --variable pc_system_libdirs pkg-config
- A platform-dependent default value 
 - Additionally, when the - ENV_MODEis- PKGCONFthe- CMAKE_PKG_CONFIG_PKGCONF_LIB_DIRSvariable will be concatenated to the list if available. If it is not available, the- LIBRARY_PATHenvironment variable will be queried and concatenated.
- ALLOW_SYSTEM_INCLUDES
- Preserves "system" directories during flag mangling of include directories in - CMAKE_PKG_CONFIG_CFLAGSand derived variables.- When this option is not provided, the default value is determined by the first available of the following values: - CMAKE_PKG_CONFIG_ALLOW_SYS_INCLUDES
- If the - PKG_CONFIG_ALLOW_SYSTEM_CFLAGSenvironment variable is defined the flags are preserved, otherwise they are filtered during flag mangling.
 
- ALLOW_SYSTEM_LIBS
- Preserves "system" directories during flag mangling of library directories in - CMAKE_PKG_CONFIG_LIBSand derived variables.- When this option is not provided, the default value is determined by the first available of the following values: - CMAKE_PKG_CONFIG_ALLOW_SYS_LIBS
- If the - PKG_CONFIG_ALLOW_SYSTEM_LIBSenvironment variable is defined the flags are preserved, otherwise they are filtered during flag mangling.
 
