| /*============================================================================ |
| 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 cmIfCommand_h |
| #define cmIfCommand_h |
| |
| #include "cmCommand.h" |
| #include "cmFunctionBlocker.h" |
| |
| class cmIfFunctionBlocker : public cmFunctionBlocker |
| { |
| public: |
| cmIfFunctionBlocker() { |
| this->HasRun = false; this->ScopeDepth = 0; } |
| virtual ~cmIfFunctionBlocker() {} |
| virtual bool IsFunctionBlocked(const cmListFileFunction& lff, |
| cmMakefile &mf, |
| cmExecutionStatus &); |
| virtual bool ShouldRemove(const cmListFileFunction& lff, |
| cmMakefile &mf); |
| |
| std::vector<cmListFileArgument> Args; |
| std::vector<cmListFileFunction> Functions; |
| bool IsBlocking; |
| bool HasRun; |
| unsigned int ScopeDepth; |
| }; |
| |
| /// Starts an if block |
| class cmIfCommand : public cmCommand |
| { |
| public: |
| /** |
| * This is a virtual constructor for the command. |
| */ |
| virtual cmCommand* Clone() |
| { |
| return new cmIfCommand; |
| } |
| |
| /** |
| * This overrides the default InvokeInitialPass implementation. |
| * It records the arguments before expansion. |
| */ |
| virtual bool InvokeInitialPass(const std::vector<cmListFileArgument>& args, |
| cmExecutionStatus &); |
| |
| /** |
| * This is called when the command is first encountered in |
| * the CMakeLists.txt file. |
| */ |
| virtual bool InitialPass(std::vector<std::string> const&, |
| cmExecutionStatus &) { return false;}; |
| |
| /** |
| * The name of the command as specified in CMakeList.txt. |
| */ |
| virtual const char* GetName() const { return "if";} |
| |
| /** |
| * Succinct documentation. |
| */ |
| virtual const char* GetTerseDocumentation() const |
| { |
| return "Conditionally execute a group of commands."; |
| } |
| |
| /** |
| * This determines if the command is invoked when in script mode. |
| */ |
| virtual bool IsScriptable() const { return true; } |
| |
| /** |
| * More documentation. |
| */ |
| virtual const char* GetFullDocumentation() const |
| { |
| return |
| " if(expression)\n" |
| " # then section.\n" |
| " COMMAND1(ARGS ...)\n" |
| " COMMAND2(ARGS ...)\n" |
| " ...\n" |
| " elseif(expression2)\n" |
| " # elseif section.\n" |
| " COMMAND1(ARGS ...)\n" |
| " COMMAND2(ARGS ...)\n" |
| " ...\n" |
| " else(expression)\n" |
| " # else section.\n" |
| " COMMAND1(ARGS ...)\n" |
| " COMMAND2(ARGS ...)\n" |
| " ...\n" |
| " endif(expression)\n" |
| "Evaluates the given expression. If the result is true, the commands " |
| "in the THEN section are invoked. Otherwise, the commands in the " |
| "else section are invoked. The elseif and else sections are " |
| "optional. You may have multiple elseif clauses. Note that " |
| "the expression in the else and endif clause is optional. Long " |
| "expressions can be used and there is a traditional order of " |
| "precedence. " |
| "Parenthetical expressions are evaluated first followed by unary " |
| "operators such as EXISTS, COMMAND, and DEFINED. " |
| "Then any EQUAL, LESS, GREATER, STRLESS, STRGREATER, STREQUAL, MATCHES " |
| "will be evaluated. Then NOT operators and finally AND, OR operators " |
| "will be evaluated. Possible expressions are:\n" |
| " if(<constant>)\n" |
| "True if the constant is 1, ON, YES, TRUE, Y, or a non-zero number. " |
| "False if the constant is 0, OFF, NO, FALSE, N, IGNORE, NOTFOUND, '', " |
| "or ends in the suffix '-NOTFOUND'. " |
| "Named boolean constants are case-insensitive. " |
| "If the argument is not one of these constants, " |
| "it is treated as a variable:" |
| "\n" |
| " if(<variable>)\n" |
| "True if the variable is defined to a value that is not a false " |
| "constant. False otherwise. " |
| "(Note macro arguments are not variables.)" |
| "\n" |
| " if(NOT <expression>)\n" |
| "True if the expression is not true." |
| "\n" |
| " if(<expr1> AND <expr2>)\n" |
| "True if both expressions would be considered true individually." |
| "\n" |
| " if(<expr1> OR <expr2>)\n" |
| "True if either expression would be considered true individually." |
| "\n" |
| " if(COMMAND command-name)\n" |
| "True if the given name is a command, macro or function that can be " |
| "invoked.\n" |
| " if(POLICY policy-id)\n" |
| "True if the given name is an existing policy " |
| "(of the form CMP<NNNN>).\n" |
| " if(TARGET target-name)\n" |
| "True if the given name is an existing target, built or imported.\n" |
| " if(EXISTS file-name)\n" |
| " if(EXISTS directory-name)\n" |
| "True if the named file or directory exists. " |
| "Behavior is well-defined only for full paths.\n" |
| " if(file1 IS_NEWER_THAN file2)\n" |
| "True if file1 is newer than file2 or if one of the two files " |
| "doesn't exist. " |
| "Behavior is well-defined only for full paths. " |
| "If the file time stamps are exactly the same, an " |
| "IS_NEWER_THAN comparison returns true, so that any dependent " |
| "build operations will occur in the event of a tie. " |
| "This includes the case of passing the same file name for both " |
| "file1 and file2.\n" |
| " if(IS_DIRECTORY directory-name)\n" |
| "True if the given name is a directory. " |
| "Behavior is well-defined only for full paths.\n" |
| " if(IS_SYMLINK file-name)\n" |
| "True if the given name is a symbolic link. " |
| "Behavior is well-defined only for full paths.\n" |
| " if(IS_ABSOLUTE path)\n" |
| "True if the given path is an absolute path.\n" |
| " if(<variable|string> MATCHES regex)\n" |
| "True if the given string or variable's value matches the given " |
| "regular expression.\n" |
| " if(<variable|string> LESS <variable|string>)\n" |
| " if(<variable|string> GREATER <variable|string>)\n" |
| " if(<variable|string> EQUAL <variable|string>)\n" |
| "True if the given string or variable's value is a valid number and " |
| "the inequality or equality is true.\n" |
| " if(<variable|string> STRLESS <variable|string>)\n" |
| " if(<variable|string> STRGREATER <variable|string>)\n" |
| " if(<variable|string> STREQUAL <variable|string>)\n" |
| "True if the given string or variable's value is lexicographically " |
| "less (or greater, or equal) than the string or variable on the right.\n" |
| " if(<variable|string> VERSION_LESS <variable|string>)\n" |
| " if(<variable|string> VERSION_EQUAL <variable|string>)\n" |
| " if(<variable|string> VERSION_GREATER <variable|string>)\n" |
| "Component-wise integer version number comparison (version format is " |
| "major[.minor[.patch[.tweak]]]).\n" |
| " if(DEFINED <variable>)\n" |
| "True if the given variable is defined. It does not matter if the " |
| "variable is true or false just if it has been set.\n" |
| " if((expression) AND (expression OR (expression)))\n" |
| "The expressions inside the parenthesis are evaluated first and " |
| "then the remaining expression is evaluated as in the previous " |
| "examples. Where there are nested parenthesis the innermost are " |
| "evaluated as part of evaluating the expression " |
| "that contains them." |
| "\n" |
| |
| "The if command was written very early in CMake's history, predating " |
| "the ${} variable evaluation syntax, and for convenience evaluates " |
| "variables named by its arguments as shown in the above signatures. " |
| "Note that normal variable evaluation with ${} applies before the " |
| "if command even receives the arguments. " |
| "Therefore code like\n" |
| " set(var1 OFF)\n" |
| " set(var2 \"var1\")\n" |
| " if(${var2})\n" |
| "appears to the if command as\n" |
| " if(var1)\n" |
| "and is evaluated according to the if(<variable>) case " |
| "documented above. " |
| "The result is OFF which is false. " |
| "However, if we remove the ${} from the example then the command sees\n" |
| " if(var2)\n" |
| "which is true because var2 is defined to \"var1\" which is not " |
| "a false constant." |
| "\n" |
| "Automatic evaluation applies in the other cases whenever the " |
| "above-documented signature accepts <variable|string>:\n" |
| |
| "1) The left hand argument to MATCHES is first checked to see " |
| "if it is a defined variable, if so the variable's value is " |
| "used, otherwise the original value is used. \n" |
| |
| "2) If the left hand argument to MATCHES is missing it returns " |
| "false without error \n" |
| |
| "3) Both left and right hand arguments to LESS GREATER EQUAL " |
| "are independently tested to see if they are defined variables, " |
| "if so their defined values are used otherwise the original " |
| "value is used. \n" |
| |
| "4) Both left and right hand arguments to STRLESS STREQUAL " |
| "STRGREATER are independently tested to see if they are defined " |
| "variables, if so their defined values are used otherwise the " |
| "original value is used. \n" |
| |
| "5) Both left and right hand argumemnts to VERSION_LESS " |
| "VERSION_EQUAL VERSION_GREATER are independently tested to see " |
| "if they are defined variables, if so their defined values are " |
| "used otherwise the original value is used. \n" |
| |
| "6) The right hand argument to NOT is tested to see if it is a " |
| "boolean constant, if so the value is used, otherwise it is " |
| "assumed to be a variable and it is dereferenced. \n" |
| |
| "7) The left and right hand arguments to AND OR are " |
| "independently tested to see if they are boolean constants, if " |
| "so they are used as such, otherwise they are assumed to be " |
| "variables and are dereferenced. \n" |
| ; |
| } |
| |
| // this is a shared function for both If and Else to determine if the |
| // arguments were valid, and if so, was the response true. If there is |
| // an error, the errorString will be set. |
| static bool IsTrue(const std::vector<std::string> &args, |
| std::string &errorString, cmMakefile *mf, |
| cmake::MessageType &status); |
| |
| // Get a definition from the makefile. If it doesn't exist, |
| // return the original string. |
| static const char* GetVariableOrString(const char* str, |
| const cmMakefile* mf); |
| |
| cmTypeMacro(cmIfCommand, cmCommand); |
| }; |
| |
| |
| #endif |
