Checking in the FindFLEX.cmake & FindBISON.cmake attached to Issue #4018 after some minor improvements

* Improved examples
* Switched to FindPackageHandleStandardArgs
* Cleaned up indentation
* Sanitized else()/endif() blocks

1 files changed, 154 insertions, 0 deletions

diff --git a/Modules/FindFLEX.cmake b/Modules/FindFLEX.cmake
new file mode 100644
index 0000000..b36fd2e
--- /dev/null
+++ b/Modules/FindFLEX.cmake
@@ -0,0 +1,154 @@
+# - Find flex executable and provides a macro to generate custom build rules
+#
+# The module defines the following variables:
+#  FLEX_FOUND - true is flex executable is found
+#  FLEX_EXECUTABLE - the path to the flex executable
+#  FLEX_VERSION - the version of flex
+#  FLEX_LIBRARIES - The flex libraries
+#
+# If flex is found on the system, the module provides the macro:
+#  FLEX_TARGET(Name FlexInput FlexOutput [COMPILE_FLAGS <string>])
+# which creates a custom command  to generate the <FlexOutput> file from
+# the <FlexInput> file.  If  COMPILE_FLAGS option is specified, the next
+# parameter is added to the flex  command line. Name is an alias used to
+# get  details of  this custom  command.  Indeed the  macro defines  the
+# following variables:
+#  FLEX_${Name}_DEFINED - true is the macro ran successfully
+#  FLEX_${Name}_OUTPUTS - the source file generated by the custom rule, an
+#  alias for FlexOutput
+#  FLEX_${Name}_INPUT - the flex source file, an alias for ${FlexInput}
+#
+# Flex scanners oftenly use tokens  defined by Bison: the code generated
+# by Flex  depends of the header  generated by Bison.   This module also
+# defines a macro:
+#  ADD_FLEX_BISON_DEPENDENCY(FlexTarget BisonTarget)
+# which  adds the  required dependency  between a  scanner and  a parser
+# where  <FlexTarget>  and <BisonTarget>  are  the  first parameters  of
+# respectively FLEX_TARGET and BISON_TARGET macros.
+#
+#====================================================================
+# Example:
+#
+#  find_package(BISON)
+#  find_package(FLEX)
+#
+#  BISON_TARGET(MyParser parser.y ${CMAKE_CURRENT_BINARY_DIR}/parser.cpp
+#  FLEX_TARGET(MyScanner lexer.l  ${CMAKE_CURRENT_BIANRY_DIR}/lexer.cpp)
+#  ADD_FLEX_BISON_DEPENDENCY(MyScanner MyParser)
+#
+#  include_directories(${CMAKE_CURRENT_BINARY_DIR})
+#  add_executable(Foo
+#     Foo.cc
+#     ${BISON_MyParser_OUTPUTS}
+#     ${FLEX_MyScanner_OUTPUTS}
+#  )
+#====================================================================
+
+# Copyright (c) 2006, Tristan Carel
+# All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above copyright
+#       notice, this list of conditions and the following disclaimer in the
+#       documentation and/or other materials provided with the distribution.
+#     * Neither the name of the University of California, Berkeley nor the
+#       names of its contributors may be used to endorse or promote products
+#       derived from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
+# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+# DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
+# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# $Id$
+
+FIND_PROGRAM(FLEX_EXECUTABLE flex DOC "path to the flex executable")
+MARK_AS_ADVANCED(FLEX_EXECUTABLE)
+
+FIND_LIBRARY(FL_LIBRARY NAMES fl
+  DOC "path to the fl library")
+MARK_AS_ADVANCED(FL_LIBRARY)
+SET(FLEX_LIBRARIES ${FL_LIBRARY})
+
+IF(FLEX_EXECUTABLE)
+
+  EXECUTE_PROCESS(COMMAND ${FLEX_EXECUTABLE} --version
+    OUTPUT_VARIABLE FLEX_version_output
+    ERROR_VARIABLE FLEX_version_error
+    RESULT_VARIABLE FLEX_version_result
+    OUTPUT_STRIP_TRAILING_WHITESPACE)
+  IF(NOT ${FLEX_version_result} EQUAL 0)
+    MESSAGE(SEND_ERROR "Command \"${FLEX_EXECUTABLE} --version\" failed with output:\n${FLEX_version_error}")
+  ELSE()
+    STRING(REGEX REPLACE "^flex (.*)$" "\\1"
+      FLEX_VERSION "${FLEX_version_output}")
+  ENDIF()
+
+  #============================================================
+  # FLEX_TARGET (public macro)
+  #============================================================
+  #
+  MACRO(FLEX_TARGET Name Input Output)
+    SET(FLEX_TARGET_usage "FLEX_TARGET(<Name> <Input> <Output> [COMPILE_FLAGS <string>]")
+    IF(${ARGC} GREATER 3)
+      IF(${ARGC} EQUAL 5)
+        IF("${ARGV3}" STREQUAL "COMPILE_FLAGS")
+          SET(FLEX_EXECUTABLE_opts  "${ARGV4}")
+          SEPARATE_ARGUMENTS(FLEX_EXECUTABLE_opts)
+        ELSE()
+          MESSAGE(SEND_ERROR ${FLEX_TARGET_usage})
+        ENDIF()
+      ELSE()
+        MESSAGE(SEND_ERROR ${FLEX_TARGET_usage})
+      ENDIF()
+    ENDIF()
+
+    ADD_CUSTOM_COMMAND(OUTPUT ${Output}
+      COMMAND ${FLEX_EXECUTABLE}
+      ARGS ${FLEX_EXECUTABLE_opts} -o${Output} ${Input}
+      DEPENDS ${Input}
+      COMMENT "[FLEX][${Name}] Building scanner with flex ${FLEX_VERSION}"
+      WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
+
+    SET(FLEX_${Name}_DEFINED TRUE)
+    SET(FLEX_${Name}_OUTPUTS ${Output})
+    SET(FLEX_${Name}_INPUT ${Input})
+    SET(FLEX_${Name}_COMPILE_FLAGS ${FLEX_EXECUTABLE_opts})
+  ENDMACRO(FLEX_TARGET)
+  #============================================================
+
+
+  #============================================================
+  # ADD_FLEX_BISON_DEPENDENCY (public macro)
+  #============================================================
+  #
+  MACRO(ADD_FLEX_BISON_DEPENDENCY FlexTarget BisonTarget)
+
+    IF(NOT FLEX_${FlexTarget}_OUTPUTS)
+      MESSAGE(SEND_ERROR "Flex target `${FlexTarget}' does not exists.")
+    ENDIF()
+
+    IF(NOT BISON_${BisonTarget}_OUTPUT_HEADER)
+      MESSAGE(SEND_ERROR "Bison target `${BisonTarget}' does not exists.")
+    ENDIF()
+
+    SET_SOURCE_FILES_PROPERTIES(${FLEX_${FlexTarget}_OUTPUTS}
+      PROPERTIES OBJECT_DEPENDS ${BISON_${BisonTarget}_OUTPUT_HEADER})
+  ENDMACRO(ADD_FLEX_BISON_DEPENDENCY)
+  #============================================================
+
+ENDIF(FLEX_EXECUTABLE)
+
+INCLUDE(FindPackageHandleStandardArgs)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(FLEX DEFAULT_MSG FLEX_EXECUTABLE)
+
+# FindFLEX.cmake ends here