CMake/Source/cmTryRunCommand.h
2012-11-07 13:51:50 -05:00

119 lines
4.6 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 cmTryRunCommand_h
#define cmTryRunCommand_h
#include "cmCoreTryCompile.h"
/** \class cmTryRunCommand
* \brief Specifies where to install some files
*
* cmTryRunCommand is used to test if soucre code can be compiled
*/
class cmTryRunCommand : public cmCoreTryCompile
{
public:
/**
* This is a virtual constructor for the command.
*/
virtual cmCommand* Clone()
{
return new cmTryRunCommand;
}
/**
* 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 "try_run";}
/**
* Succinct documentation.
*/
virtual const char* GetTerseDocumentation() const
{
return "Try compiling and then running some code.";
}
/**
* More documentation.
*/
virtual const char* GetFullDocumentation() const
{
return
" try_run(RUN_RESULT_VAR COMPILE_RESULT_VAR\n"
" bindir srcfile [CMAKE_FLAGS <Flags>]\n"
" [COMPILE_DEFINITIONS <flags>]\n"
" [COMPILE_OUTPUT_VARIABLE comp]\n"
" [RUN_OUTPUT_VARIABLE run]\n"
" [OUTPUT_VARIABLE var]\n"
" [ARGS <arg1> <arg2>...])\n"
"Try compiling a srcfile. Return TRUE or FALSE for success or failure "
"in COMPILE_RESULT_VAR. Then if the compile succeeded, run the "
"executable and return its exit code in RUN_RESULT_VAR. "
"If the executable was built, but failed to run, then RUN_RESULT_VAR "
"will be set to FAILED_TO_RUN. "
"COMPILE_OUTPUT_VARIABLE specifies the variable where the output from "
"the compile step goes. RUN_OUTPUT_VARIABLE specifies the variable "
"where the output from the running executable goes.\n"
"For compatibility reasons OUTPUT_VARIABLE is still supported, which "
"gives you the output from the compile and run step combined.\n"
"Cross compiling issues\n"
"When cross compiling, the executable compiled in the first step "
"usually cannot be run on the build host. try_run() checks the "
"CMAKE_CROSSCOMPILING variable to detect whether CMake is in "
"crosscompiling mode. If that's the case, it will still try to compile "
"the executable, but it will not try to run the executable. Instead it "
"will create cache variables which must be filled by the user or by "
"presetting them in some CMake script file to the values the "
"executable would have produced if it had been run on its actual "
"target platform. These variables are RUN_RESULT_VAR (explanation see "
"above) and if RUN_OUTPUT_VARIABLE (or OUTPUT_VARIABLE) was used, an "
"additional cache variable "
"RUN_RESULT_VAR__COMPILE_RESULT_VAR__TRYRUN_OUTPUT."
"This is intended to hold stdout and stderr from the executable.\n"
"In order to make cross compiling your project easier, use try_run "
"only if really required. If you use try_run, use RUN_OUTPUT_VARIABLE "
"(or OUTPUT_VARIABLE) only if really required. Using them will require "
"that when crosscompiling, the cache variables will have to be set "
"manually to the output of the executable. You can also \"guard\" the "
"calls to try_run with if(CMAKE_CROSSCOMPILING) and provide an "
"easy-to-preset alternative for this case.\n"
"Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build "
"configuration."
;
}
cmTypeMacro(cmTryRunCommand, cmCoreTryCompile);
private:
void RunExecutable(const std::string& runArgs,
std::string* runOutputContents);
void DoNotRunExecutable(const std::string& runArgs,
const std::string& srcFile,
std::string* runOutputContents);
std::string CompileResultVariable;
std::string RunResultVariable;
std::string OutputVariable;
std::string RunOutputVariable;
std::string CompileOutputVariable;
};
#endif