From 7b2816cc3a34d5c8c66c23170e3dde68ad1e314e Mon Sep 17 00:00:00 2001
From: Andreas Schneider <mail@cynapses.org>
Date: Thu, 11 Mar 2010 11:12:03 +0100
Subject: [PATCH 2/2] Added a check to verify that a protoype we expect is correct.

This check if the function exists and the prototype we want to use is
correct. There are still functions which have different prototypes on
UNICES.

check_prototype_definition(getpwent_r
     "struct passwd *getpwent_r(struct passwd *src, char *buf, int buflen)"
     "NULL"
     "unistd.h;pwd.h"
     SOLARIS_GETPWENT_R)

Signed-off-by: Andreas Schneider <mail@cynapses.org>
---
 Modules/CheckPrototypeDefinition.c.in  |   29 +++++++++++
 Modules/CheckPrototypeDefinition.cmake |   86 ++++++++++++++++++++++++++++++++
 2 files changed, 115 insertions(+), 0 deletions(-)
 create mode 100644 Modules/CheckPrototypeDefinition.c.in
 create mode 100644 Modules/CheckPrototypeDefinition.cmake

diff --git a/Modules/CheckPrototypeDefinition.c.in b/Modules/CheckPrototypeDefinition.c.in
new file mode 100644
index 0000000..a97344a
--- /dev/null
+++ b/Modules/CheckPrototypeDefinition.c.in
@@ -0,0 +1,29 @@
+@CHECK_PROTOTYPE_DEFINITION_HEADER@
+
+static void cmakeRequireSymbol(int dummy, ...) {
+  (void) dummy;
+}
+
+static void checkSymbol(void) {
+#ifndef @CHECK_PROTOTYPE_DEFINITION_SYMBOL@
+  cmakeRequireSymbol(0, &@CHECK_PROTOTYPE_DEFINITION_SYMBOL@);
+#endif
+}
+
+@CHECK_PROTOTYPE_DEFINITION_PROTO@ {
+  return @CHECK_PROTOTYPE_DEFINITION_RETURN@;
+}
+
+#ifdef __CLASSIC_C__
+int main() {
+  int ac;
+  char*av[];
+#else
+int main(int ac, char *av[]) {
+#endif
+  checkSymbol();
+  if (ac > 1000) {
+    return *av[0];
+  }
+  return 0;
+}
diff --git a/Modules/CheckPrototypeDefinition.cmake b/Modules/CheckPrototypeDefinition.cmake
new file mode 100644
index 0000000..3a53f66
--- /dev/null
+++ b/Modules/CheckPrototypeDefinition.cmake
@@ -0,0 +1,86 @@
+# - Check if the protoype we expect is correct.
+# check_prototype_definition(FUNCTION PROTOTYPE RETURN HEADER VARIABLE)
+#
+#  FUNCTION - The name of the function (used to check if prototype exists)
+#  PROTOTYPE- The prototype to check.
+#  RETURN - The return value of the function.
+#  HEADER - The header files required.
+#  VARIABLE - The variable to store the result.
+#
+# Example:
+#
+# check_prototype_definition(getpwent_r
+#     "struct passwd *getpwent_r(struct passwd *src, char *buf, int buflen)"
+#     "NULL"
+#     "unistd.h;pwd.h"
+#     SOLARIS_GETPWENT_R)
+#
+# The following variables may be set before calling this macro to
+# modify the way the check is run:
+#
+#  CMAKE_REQUIRED_FLAGS = string of compile command line flags
+#  CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
+#  CMAKE_REQUIRED_INCLUDES = list of include directories
+#  CMAKE_REQUIRED_LIBRARIES = list of libraries to link
+
+
+function(CHECK_PROTOTYPE_DEFINITION _FUNCTION _PROTOTYPE _RETURN _HEADER _VARIABLE)
+
+    if ("${_VARIABLE}" MATCHES "^${_VARIABLE}$")
+        set(CHECK_PROTOTYPE_DEFINITION_CONTENT "/* */\n")
+
+        set(CHECK_PROTOTYPE_DEFINITION_FLAGS ${CMAKE_REQUIRED_FLAGS})
+        if (CMAKE_REQUIRED_LIBRARIES)
+          set(CHECK_PROTOTYPE_DEFINITION_LIBS
+              "-DLINK_LIBRARIES:STRING=${CMAKE_REQUIRED_LIBRARIES}")
+        else(CMAKE_REQUIRED_LIBRARIES)
+            set(CHECK_PROTOTYPE_DEFINITION_LIBS)
+        endif(CMAKE_REQUIRED_LIBRARIES)
+        if (CMAKE_REQUIRED_INCLUDES)
+            set(CMAKE_SYMBOL_EXISTS_INCLUDES
+                "-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
+        else(CMAKE_REQUIRED_INCLUDES)
+            set(CMAKE_SYMBOL_EXISTS_INCLUDES)
+        endif(CMAKE_REQUIRED_INCLUDES)
+
+        foreach(_FILE ${_HEADER})
+          set(CHECK_PROTOTYPE_DEFINITION_HEADER
+            "${CHECK_PROTOTYPE_DEFINITION_HEADER}#include <${_FILE}>\n")
+        endforeach(_FILE)
+
+        set(CHECK_PROTOTYPE_DEFINITION_SYMBOL ${_FUNCTION})
+        set(CHECK_PROTOTYPE_DEFINITION_PROTO ${_PROTOTYPE})
+        set(CHECK_PROTOTYPE_DEFINITION_RETURN ${_RETURN})
+
+        #configure_file("${CMAKE_ROOT}/Modules/CheckPrototypeDefinition.c.in"
+        #  "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckPrototypeDefinition.c" @ONLY)
+        configure_file("${CMAKE_MODULE_PATH}/CheckPrototypeDefinition.c.in"
+            "${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckPrototypeDefinition.c" @ONLY)
+
+        file(READ ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckPrototypeDefinition.c _SOURCE)
+
+        try_compile(${_VARIABLE}
+          ${CMAKE_BINARY_DIR}
+          ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckPrototypeDefinition.c
+          COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
+          CMAKE_FLAGS -DCOMPILE_DEFINITIONS:STRING=${CHECK_PROTOTYPE_DEFINITION_FLAGS}
+          "${CHECK_PROTOTYPE_DEFINITION_LIBS}"
+          "${CMAKE_SYMBOL_EXISTS_INCLUDES}"
+          OUTPUT_VARIABLE OUTPUT)
+
+        if (${_VARIABLE})
+            set(${_VARIABLE} 1 CACHE INTERNAL "Have correct prototype for ${_FUNCTION}")
+            message(STATUS "Checking prototype ${_FUNCTION} for ${_VARIABLE} - True")
+            file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
+                "Determining if the prototype ${_FUNCTION} exists for ${_VARIABLE} passed with the following output:\n"
+                "${OUTPUT}\n\n")
+        else (${_VARIABLE})
+            message(STATUS "Checking prototype ${_FUNCTION} for ${_VARIABLE} - False")
+            set(${_VARIABLE} 0 CACHE INTERNAL "Have correct prototype for ${_FUNCTION}")
+            file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
+                "Determining if the prototype ${_FUNCTION} exists for ${_VARIABLE} failed with the following output:\n"
+                "${OUTPUT}\n\n${_SOURCE}\n\n")
+        endif (${_VARIABLE})
+    endif("${_VARIABLE}" MATCHES "^${_VARIABLE}$")
+
+endfunction(CHECK_PROTOTYPE_DEFINITION)
-- 
1.7.0.1