CMake/Source/cmTargetLinkLibrariesCommand.h
Stephen Kelly b655865bbf target_link_libraries: Add PUBLIC/PRIVATE/INTERFACE keyword signature
Add a new signature to help populate INTERFACE_LINK_LIBRARIES and
LINK_LIBRARIES cleanly in a single call.  Add policy CMP0023 to control
whether the keyword signatures can be mixed with uses of the plain
signatures on the same target.
2013-07-24 11:52:44 -04:00

217 lines
9.7 KiB
C++

/*============================================================================
CMake - Cross Platform Makefile Generator
Copyright 2000-2009 Kitware, Inc., Insight Software Consortium
Distributed under the OSI-approved BSD License (the "License");
see accompanying file Copyright.txt for details.
This software is distributed WITHOUT ANY WARRANTY; without even the
implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the License for more information.
============================================================================*/
#ifndef cmTargetLinkLibrariesCommand_h
#define cmTargetLinkLibrariesCommand_h
#include "cmCommand.h"
#include "cmDocumentGeneratorExpressions.h"
/** \class cmTargetLinkLibrariesCommand
* \brief Specify a list of libraries to link into executables.
*
* cmTargetLinkLibrariesCommand is used to specify a list of libraries to link
* into executable(s) or shared objects. The names of the libraries
* should be those defined by the LIBRARY(library) command(s).
*/
class cmTargetLinkLibrariesCommand : public cmCommand
{
public:
/**
* This is a virtual constructor for the command.
*/
virtual cmCommand* Clone()
{
return new cmTargetLinkLibrariesCommand;
}
/**
* This is called when the command is first encountered in
* the CMakeLists.txt file.
*/
virtual bool InitialPass(std::vector<std::string> const& args,
cmExecutionStatus &status);
/**
* The name of the command as specified in CMakeList.txt.
*/
virtual const char* GetName() const { return "target_link_libraries";}
/**
* Succinct documentation.
*/
virtual const char* GetTerseDocumentation() const
{
return
"Link a target to given libraries.";
}
/**
* More documentation.
*/
virtual const char* GetFullDocumentation() const
{
return
" target_link_libraries(<target> [item1 [item2 [...]]]\n"
" [[debug|optimized|general] <item>] ...)\n"
"Specify libraries or flags to use when linking a given target. "
"The named <target> must have been created in the current directory "
"by a command such as add_executable or add_library. "
"The remaining arguments specify library names or flags. "
"Repeated calls for the same <target> append items in the order called."
"\n"
"If a library name matches that of another target in the project "
"a dependency will automatically be added in the build system to make "
"sure the library being linked is up-to-date before the target links. "
"Item names starting with '-', but not '-l' or '-framework', are "
"treated as linker flags."
"\n"
"A \"debug\", \"optimized\", or \"general\" keyword indicates that "
"the library immediately following it is to be used only for the "
"corresponding build configuration. "
"The \"debug\" keyword corresponds to the Debug configuration "
"(or to configurations named in the DEBUG_CONFIGURATIONS global "
"property if it is set). "
"The \"optimized\" keyword corresponds to all other configurations. "
"The \"general\" keyword corresponds to all configurations, and is "
"purely optional (assumed if omitted). "
"Higher granularity may be achieved for per-configuration rules "
"by creating and linking to IMPORTED library targets. "
"See the IMPORTED mode of the add_library command for more "
"information. "
"\n"
"Library dependencies are transitive by default. "
"When this target is linked into another target then the libraries "
"linked to this target will appear on the link line for the other "
"target too. "
"See the INTERFACE_LINK_LIBRARIES target property to override the "
"set of transitive link dependencies for a target. "
"Calls to other signatures of this command may set the property "
"making any libraries linked exclusively by this signature private."
"\n"
"CMake will also propagate \"usage requirements\" from linked library "
"targets. "
"Usage requirements affect compilation of sources in the <target>. "
"They are specified by properties defined on linked targets. "
"During generation of the build system, CMake integrates "
"usage requirement property values with the corresponding "
"build properties for <target>:\n"
" INTERFACE_COMPILE_DEFINITONS: Appends to COMPILE_DEFINITONS\n"
" INTERFACE_INCLUDE_DIRECTORIES: Appends to INCLUDE_DIRECTORIES\n"
" INTERFACE_POSITION_INDEPENDENT_CODE: Sets POSITION_INDEPENDENT_CODE\n"
" or checked for consistency with existing value\n"
"\n"
"If an <item> is a library in a Mac OX framework, the Headers "
"directory of the framework will also be processed as a \"usage "
"requirement\". This has the same effect as passing the framework "
"directory as an include directory."
" target_link_libraries(<target>\n"
" <PRIVATE|PUBLIC|INTERFACE> <lib> ...\n"
" [<PRIVATE|PUBLIC|INTERFACE> <lib> ... ] ...])\n"
"The PUBLIC, PRIVATE and INTERFACE keywords can be used to specify "
"both the link dependencies and the link interface in one command. "
"Libraries and targets following PUBLIC are linked to, and are "
"made part of the link interface. Libraries and targets "
"following PRIVATE are linked to, but are not made part of the "
"link interface. Libraries following INTERFACE are appended "
"to the link interface and are not used for linking <target>."
"\n"
" target_link_libraries(<target> LINK_INTERFACE_LIBRARIES\n"
" [[debug|optimized|general] <lib>] ...)\n"
"The LINK_INTERFACE_LIBRARIES mode appends the libraries "
"to the INTERFACE_LINK_LIBRARIES target property instead of using them "
"for linking. If policy CMP0022 is not NEW, then this mode also "
"appends libraries to the LINK_INTERFACE_LIBRARIES and its "
"per-configuration equivalent. This signature "
"is for compatibility only. Prefer the INTERFACE mode instead. "
"Libraries specified as \"debug\" are wrapped in a generator "
"expression to correspond to debug builds. If policy CMP0022 is not "
"NEW, the libraries are also appended to the "
"LINK_INTERFACE_LIBRARIES_DEBUG property (or to the properties "
"corresponding to configurations listed in the DEBUG_CONFIGURATIONS "
"global property if it is set). "
"Libraries specified as \"optimized\" are appended to the "
"INTERFACE_LINK_LIBRARIES property. If policy CMP0022 is not NEW, "
"they are also appended to the LINK_INTERFACE_LIBRARIES property. "
"Libraries specified as \"general\" (or without any keyword) are "
"treated as if specified for both \"debug\" and \"optimized\"."
"\n"
" target_link_libraries(<target>\n"
" <LINK_PRIVATE|LINK_PUBLIC>\n"
" [[debug|optimized|general] <lib>] ...\n"
" [<LINK_PRIVATE|LINK_PUBLIC>\n"
" [[debug|optimized|general] <lib>] ...])\n"
"The LINK_PUBLIC and LINK_PRIVATE modes can be used to specify both "
"the link dependencies and the link interface in one command. This "
"signature is for compatibility only. Prefer the PUBLIC or PRIVATE "
"keywords instead. "
"Libraries and targets following LINK_PUBLIC are linked to, and are "
"made part of the INTERFACE_LINK_LIBRARIES. If policy CMP0022 is not "
"NEW, they are also made part of the LINK_INTERFACE_LIBRARIES. "
"Libraries and targets following LINK_PRIVATE are linked to, but are "
"not made part of the INTERFACE_LINK_LIBRARIES (or "
"LINK_INTERFACE_LIBRARIES)."
"\n"
"The library dependency graph is normally acyclic (a DAG), but in the "
"case of mutually-dependent STATIC libraries CMake allows the graph "
"to contain cycles (strongly connected components). "
"When another target links to one of the libraries CMake repeats "
"the entire connected component. "
"For example, the code\n"
" add_library(A STATIC a.c)\n"
" add_library(B STATIC b.c)\n"
" target_link_libraries(A B)\n"
" target_link_libraries(B A)\n"
" add_executable(main main.c)\n"
" target_link_libraries(main A)\n"
"links 'main' to 'A B A B'. "
"("
"While one repetition is usually sufficient, pathological object "
"file and symbol arrangements can require more. "
"One may handle such cases by manually repeating the component in "
"the last target_link_libraries call. "
"However, if two archives are really so interdependent they should "
"probably be combined into a single archive."
")"
"\n"
"Arguments to target_link_libraries may use \"generator expressions\" "
"with the syntax \"$<...>\". Note however, that generator expressions "
"will not be used in OLD handling of CMP0003 or CMP0004."
"\n"
CM_DOCUMENT_COMMAND_GENERATOR_EXPRESSIONS
;
}
cmTypeMacro(cmTargetLinkLibrariesCommand, cmCommand);
private:
void LinkLibraryTypeSpecifierWarning(int left, int right);
static const char* LinkLibraryTypeNames[3];
cmTarget* Target;
enum ProcessingState {
ProcessingLinkLibraries,
ProcessingPlainLinkInterface,
ProcessingKeywordLinkInterface,
ProcessingPlainPublicInterface,
ProcessingKeywordPublicInterface,
ProcessingPlainPrivateInterface,
ProcessingKeywordPrivateInterface
};
ProcessingState CurrentProcessingState;
bool HandleLibrary(const char* lib, cmTarget::LinkLibraryType llt);
};
#endif