From: Azat Khuzhin <a3at.mail@gmail.com>
Date: Mon, 30 Jan 2017 00:17:41 +0000 (+0300)
Subject: cmake: Fix checking of enum values from sysctl.h
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=fa135bdcd9f82a953ac6be55a5c874114bccbc42;p=libevent

cmake: Fix checking of enum values from sysctl.h

CheckSymbolExists do not do this, so add new CheckConstExists that will
use CheckCSourceCompiles() to check this.

v2: use set() instead of string(APPEND)
---

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 24eaa404..ae6178b1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -52,6 +52,7 @@ include(CheckStructHasMember)
 include(CheckCSourceCompiles)
 include(CheckPrototypeDefinition)
 include(CheckFunctionKeywords)
+include(CheckConstExists)
 include(AddCompilerFlags)
 include(VersionViaGit)
 
@@ -412,10 +413,10 @@ else()
 endif()
 
 CHECK_SYMBOL_EXISTS(TAILQ_FOREACH sys/queue.h EVENT__HAVE_TAILQFOREACH)
-CHECK_SYMBOL_EXISTS(CTL_KERN sys/sysctl.h EVENT__HAVE_DECL_CTL_KERN)
-CHECK_SYMBOL_EXISTS(KERN_ARND sys/sysctl.h EVENT__HAVE_DECL_KERN_ARND)
-CHECK_SYMBOL_EXISTS(KERN_RANDOM sys/sysctl.h EVENT__HAVE_DECL_KERN_RANDOM)
-CHECK_SYMBOL_EXISTS(RANDOM_UUID sys/sysctl.h EVENT__HAVE_DECL_RANDOM_UUID)
+CHECK_CONST_EXISTS(CTL_KERN sys/sysctl.h EVENT__HAVE_DECL_CTL_KERN)
+CHECK_CONST_EXISTS(KERN_ARND sys/sysctl.h EVENT__HAVE_DECL_KERN_ARND)
+CHECK_CONST_EXISTS(KERN_RANDOM sys/sysctl.h EVENT__HAVE_DECL_KERN_RANDOM)
+CHECK_CONST_EXISTS(RANDOM_UUID sys/sysctl.h EVENT__HAVE_DECL_RANDOM_UUID)
 CHECK_SYMBOL_EXISTS(F_SETFD fcntl.h EVENT__HAVE_SETFD)
 
 CHECK_TYPE_SIZE(fd_mask EVENT__HAVE_FD_MASK)
diff --git a/cmake/CheckConstExists.cmake b/cmake/CheckConstExists.cmake
new file mode 100644
index 00000000..56b49882
--- /dev/null
+++ b/cmake/CheckConstExists.cmake
@@ -0,0 +1,23 @@
+include(CheckCSourceCompiles)
+
+macro(check_const_exists CONST FILES VARIABLE)
+  set(check_const_exists_source "")
+  foreach(file ${FILES})
+    set(check_const_exists_source
+        "${check_const_exists_source}
+        #include <${file}>")
+  endforeach()
+  set(check_const_exists_source
+      "${check_const_exists_source}
+      int main() { (void)${CONST}; return 0; }")
+
+  check_c_source_compiles("${check_const_exists_source}" ${VARIABLE})
+
+  if (${${VARIABLE}})
+    set(${VARIABLE} 1 CACHE INTERNAL "Have const ${CONST}")
+    message(STATUS "Looking for ${CONST} - found")
+  else()
+    set(${VARIABLE} 0 CACHE INTERNAL "Have const ${CONST}")
+    message(STATUS "Looking for ${CONST} - not found")
+  endif()
+endmacro(check_const_exists)
diff --git a/event-config.h.cmake b/event-config.h.cmake
index 472ffe17..8431dfc8 100644
--- a/event-config.h.cmake
+++ b/event-config.h.cmake
@@ -67,13 +67,16 @@
 #cmakedefine EVENT__HAVE_CLOCK_GETTIME
 
 /* Define to 1 if you have the declaration of `CTL_KERN'. */
-#cmakedefine EVENT__HAVE_DECL_CTL_KERN
+#define EVENT__HAVE_DECL_CTL_KERN @EVENT__HAVE_DECL_CTL_KERN@
 
 /* Define to 1 if you have the declaration of `KERN_ARND'. */
-#cmakedefine EVENT__HAVE_DECL_KERN_ARND
+#define EVENT__HAVE_DECL_KERN_ARND @EVENT__HAVE_DECL_KERN_ARND@
 
 /* Define to 1 if you have the declaration of `KERN_RANDOM'. */
-#cmakedefine EVENT__HAVE_DECL_KERN_RANDOM
+#define EVENT__HAVE_DECL_KERN_RANDOM @EVENT__HAVE_DECL_KERN_RANDOM@
+
+/* Define to 1 if you have the declaration of `RANDOM_UUID'. */
+#define EVENT__HAVE_DECL_RANDOM_UUID @EVENT__HAVE_DECL_RANDOM_UUID@
 
 /* Define if /dev/poll is available */
 #cmakedefine EVENT__HAVE_DEVPOLL