Source/cmTargetLinkLibrariesCommand.h

   1 /*=========================================================================
   2
   3   Program:   CMake - Cross-Platform Makefile Generator
   4   Module:    $RCSfile: cmTargetLinkLibrariesCommand.h,v $
   5   Language:  C++
   6   Date:      $Date: 2009-06-24 17:24:50 $
   7   Version:   $Revision: 1.21 $
   8
   9   Copyright (c) 2002 Kitware, Inc., Insight Consortium.  All rights reserved.
  10   See Copyright.txt or http://www.cmake.org/HTML/Copyright.html for details.
  11
  12      This software is distributed WITHOUT ANY WARRANTY; without even
  13      the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  14      PURPOSE.  See the above copyright notices for more information.
  15
  16 =========================================================================*/
  17 #ifndef cmTargetLinkLibrariesCommand_h
  18 #define cmTargetLinkLibrariesCommand_h
  19
  20 #include "cmCommand.h"
  21
  22 /** \class cmTargetLinkLibrariesCommand
  23  * \brief Specify a list of libraries to link into executables.
  24  *
  25  * cmTargetLinkLibrariesCommand is used to specify a list of libraries to link
  26  * into executable(s) or shared objects. The names of the libraries
  27  * should be those defined by the LIBRARY(library) command(s).
  28  */
  29 class cmTargetLinkLibrariesCommand : public cmCommand
  30 {
  31 public:
  32   /**
  33    * This is a virtual constructor for the command.
  34    */
  35   virtual cmCommand* Clone()
  36     {
  37     return new cmTargetLinkLibrariesCommand;
  38     }
  39
  40   /**
  41    * This is called when the command is first encountered in
  42    * the CMakeLists.txt file.
  43    */
  44   virtual bool InitialPass(std::vector<std::string> const& args,
  45                            cmExecutionStatus &status);
  46
  47   /**
  48    * The name of the command as specified in CMakeList.txt.
  49    */
  50   virtual const char* GetName() { return "target_link_libraries";}
  51
  52   /**
  53    * Succinct documentation.
  54    */
  55   virtual const char* GetTerseDocumentation()
  56     {
  57     return
  58       "Link a target to given libraries.";
  59     }
  60
  61   /**
  62    * More documentation.
  63    */
  64   virtual const char* GetFullDocumentation()
  65     {
  66     return
  67       "  target_link_libraries(<target> [item1 [item2 [...]]]\n"
  68       "                        [[debug|optimized|general] <item>] ...)\n"
  69       "Specify libraries or flags to use when linking a given target.  "
  70       "If a library name matches that of another target in the project "
  71       "a dependency will automatically be added in the build system to make "
  72       "sure the library being linked is up-to-date before the target links.  "
  73       "Item names starting with '-', but not '-l' or '-framework', are "
  74       "treated as linker flags."
  75       "\n"
  76       "A \"debug\", \"optimized\", or \"general\" keyword indicates that "
  77       "the library immediately following it is to be used only for the "
  78       "corresponding build configuration.  "
  79       "The \"debug\" keyword corresponds to the Debug configuration "
  80       "(or to configurations named in the DEBUG_CONFIGURATIONS global "
  81       "property if it is set).  "
  82       "The \"optimized\" keyword corresponds to all other configurations.  "
  83       "The \"general\" keyword corresponds to all configurations, and is "
  84       "purely optional (assumed if omitted).  "
  85       "Higher granularity may be achieved for per-configuration rules "
  86       "by creating and linking to IMPORTED library targets.  "
  87       "See the IMPORTED mode of the add_library command for more "
  88       "information.  "
  89       "\n"
  90       "Library dependencies are transitive by default.  "
  91       "When this target is linked into another target then the libraries "
  92       "linked to this target will appear on the link line for the other "
  93       "target too.  "
  94       "See the LINK_INTERFACE_LIBRARIES target property to override the "
  95       "set of transitive link dependencies for a target."
  96       "\n"
  97       "  target_link_libraries(<target> LINK_INTERFACE_LIBRARIES\n"
  98       "                        [[debug|optimized|general] <lib>] ...)\n"
  99       "The LINK_INTERFACE_LIBRARIES mode appends the libraries "
 100       "to the LINK_INTERFACE_LIBRARIES and its per-configuration equivalent "
 101       "target properties instead of using them for linking.  "
 102       "Libraries specified as \"debug\" are appended to the "
 103       "the LINK_INTERFACE_LIBRARIES_DEBUG property (or to the properties "
 104       "corresponding to configurations listed in the DEBUG_CONFIGURATIONS "
 105       "global property if it is set).  "
 106       "Libraries specified as \"optimized\" are appended to the "
 107       "the LINK_INTERFACE_LIBRARIES property.  "
 108       "Libraries specified as \"general\" (or without any keyword) are "
 109       "treated as if specified for both \"debug\" and \"optimized\"."
 110       "\n"
 111       "The library dependency graph is normally acyclic (a DAG), but in the "
 112       "case of mutually-dependent STATIC libraries CMake allows the graph "
 113       "to contain cycles (strongly connected components).  "
 114       "When another target links to one of the libraries CMake repeats "
 115       "the entire connected component.  "
 116       "For example, the code\n"
 117       "  add_library(A STATIC a.c)\n"
 118       "  add_library(B STATIC b.c)\n"
 119       "  target_link_libraries(A B)\n"
 120       "  target_link_libraries(B A)\n"
 121       "  add_executable(main main.c)\n"
 122       "  target_link_libraries(main A)\n"
 123       "links 'main' to 'A B A B'.  "
 124       "("
 125       "While one repetition is usually sufficient, pathological object "
 126       "file and symbol arrangements can require more.  "
 127       "One may handle such cases by manually repeating the component in "
 128       "the last target_link_libraries call.  "
 129       "However, if two archives are really so interdependent they should "
 130       "probably be combined into a single archive."
 131       ")"
 132       ;
 133     }
 134
 135   cmTypeMacro(cmTargetLinkLibrariesCommand, cmCommand);
 136 private:
 137   void LinkLibraryTypeSpecifierWarning(int left, int right);
 138   static const char* LinkLibraryTypeNames[3];
 139
 140   cmTarget* Target;
 141   bool DoingInterface;
 142
 143   void HandleLibrary(const char* lib, cmTarget::LinkLibraryType llt);
 144 };
 145
 146
 147
 148 #endif