Resolve regular expression engines

CMakeLists.txt

@@ -77,6 +77,12 @@ message("-- Version: ${VERSION}")
 set(GENERIC_LIB_VERSION ${VERSION})
 string(SUBSTRING ${VERSION} 0 1 GENERIC_LIB_SOVERSION)
 
+# C++ feature checks
+include(CXXFeatureCheck)
+cxx_feature_check(STD_REGEX)
+cxx_feature_check(GNU_POSIX_REGEX)
+cxx_feature_check(POSIX_REGEX)
+
 # Set up directories
 include_directories(${PROJECT_SOURCE_DIR}/include)
 include_directories(${PROJECT_SOURCE_DIR}/src)

cmake/AddCXXCompilerFlag.cmake

-# - Adds a compiler FLAG if it is supported by the compiler
+# - Adds a compiler flag if it is supported by the compiler
 #
-# This function checks that the supplied compiler FLAG is supported and then
-# adds it to the corresponding compiler FLAGs
+# This function checks that the supplied compiler flag is supported and then
+# adds it to the corresponding compiler flags
 #
-#  add_cxx_compiler_FLAG(<FLAG> [<VARIANT>])
+#  add_cxx_compiler_flag(<FLAG> [<VARIANT>])
 #
 # - Example
 #
 # include(AddCXXCompilerFlag)
-# add_cxx_compiler_FLAG(-Wall)
-# add_cxx_compiler_FLAG(-no-strict-aliasing RELEASE)
+# add_cxx_compiler_flag(-Wall)
+# add_cxx_compiler_flag(-no-strict-aliasing RELEASE)
 # Requires CMake 2.6+
 
-if(__add_cxx_compiler_FLAG)
+if(__add_cxx_compiler_flag)
   return()
 endif()
-set(__add_cxx_compiler_FLAG INCLUDED)
+set(__add_cxx_compiler_flag INCLUDED)
 
 include(CheckCXXCompilerFlag)
 

cmake/CXXFeatureCheck.cmake

+# - Compile and run code to check for C++ features
+#
+# This functions compiles a source file under the `cmake` folder
+# and adds the corresponding `HAVE_[FILENAME]` flag to the CMake
+# environment
+#
+#  add_cxx_compiler_FLAG(<FLAG> [<VARIANT>])
+#
+# - Example
+#
+# include(AddCXXCompilerFlag)
+# add_cxx_compiler_FLAG(-Wall)
+# add_cxx_compiler_FLAG(-no-strict-aliasing RELEASE)
+# Requires CMake 2.6+
+
+if(__cxx_feature_check_FLAG)
+  return()
+endif()
+set(__cxx_feature_check_FLAG INCLUDED)
+
+function(cxx_feature_check FILE)
+  string(TOLOWER ${FILE} FILE)
+  string(TOUPPER ${FILE} VAR)
+  string(TOUPPER "HAVE_${VAR}" FEATURE)
+  message("-- Performing Test ${FEATURE}")
+  try_run(RUN_${FEATURE} COMPILE_${FEATURE} ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/${FILE}.cpp)
+  if(RUN_${FEATURE} EQUAL 0)
+    message("-- Performing Test ${FEATURE} -- Success")
+    set(HAVE_${VAR} 1 PARENT_SCOPE)
+    add_definitions(-DHAVE_${VAR})
+  else()
+    message("-- Performing Test ${FEATURE} -- Failed")
+  endif()
+endfunction()
+

cmake/gnu_posix_regex.cpp

+#include <gnuregex.h>
+#include <string>
+int main() {
+  std::string str = "test0159";
+  regex_t re;
+  int ec = regcomp(&re, "^[a-z]+[0-9]+$", REG_EXTENDED | REG_NOSUB);
+  if (ec != 0) {
+    return ec;
+  }
+  return regexec(&re, str.c_str(), 0, NULL, 0) ? -1 : 0;
+}
+

cmake/posix_regex.cpp

+#include <regex.h>
+#include <string>
+int main() {
+  std::string str = "test0159";
+  regex_t re;
+  int ec = regcomp(&re, "^[a-z]+[0-9]+$", REG_EXTENDED | REG_NOSUB);
+  if (ec != 0) {
+    return ec;
+  }
+  return regexec(&re, str.c_str(), 0, NULL, 0)  ? -1 : 0;
+}
+

cmake/std_regex.cpp

+#include <regex>
+#include <string>
+int main() {
+  const std::string str = "test0159";
+  const std::regex re("^[a-z]+[0-9]+$", std::regex_constants::extended | std::regex_constants::nosubs);
+  return std::regex_search(str, re) ? 0 : -1;
+}
+