cmake: add feature checks for memrchr and getifaddrs

- `HAVE_MEMRCHR` for `memrchr`.
- `HAVE_GETIFADDRS` for `getifaddrs`.
  This was present in `lib/curl_config.h.cmake` but missed the detection
  logic.

To match existing autotools feature checks.

Closes #11954

CMake/Platforms/WindowsCache.cmake

@@ -88,6 +88,7 @@ if(NOT UNIX)
     set(HAVE_STRDUP 1)
     set(HAVE_STRICMP 1)
     set(HAVE_STRCMPI 1)
+    set(HAVE_MEMRCHR 0)
     set(HAVE_GETTIMEOFDAY 0)
     set(HAVE_CLOSESOCKET 1)
     set(HAVE_SIGSETJMP 0)
@@ -102,6 +103,7 @@ if(NOT UNIX)
     set(HAVE_LINUX_TCP_H 0)
     set(HAVE_GLIBC_STRERROR_R 0)
     set(HAVE_MACH_ABSOLUTE_TIME 0)
+    set(HAVE_GETIFADDRS 0)
 
     set(HAVE_GETHOSTBYNAME_R_3 0)
     set(HAVE_GETHOSTBYNAME_R_3_REENTRANT 0)

CMakeLists.txt

@@ -1088,6 +1088,7 @@ check_symbol_exists(strtok_r      "${CURL_INCLUDES};string.h" HAVE_STRTOK_R)
 check_symbol_exists(strcasecmp    "${CURL_INCLUDES};string.h" HAVE_STRCASECMP)
 check_symbol_exists(stricmp       "${CURL_INCLUDES};string.h" HAVE_STRICMP)
 check_symbol_exists(strcmpi       "${CURL_INCLUDES};string.h" HAVE_STRCMPI)
+check_symbol_exists(memrchr       "${CURL_INCLUDES};string.h" HAVE_MEMRCHR)
 check_symbol_exists(alarm         "${CURL_INCLUDES}" HAVE_ALARM)
 check_symbol_exists(getppid       "${CURL_INCLUDES}" HAVE_GETPPID)
 check_symbol_exists(utimes        "${CURL_INCLUDES}" HAVE_UTIMES)
@@ -1109,6 +1110,7 @@ check_symbol_exists(strtoll        "${CURL_INCLUDES};stdlib.h" HAVE_STRTOLL)
 check_symbol_exists(strerror_r     "${CURL_INCLUDES};stdlib.h;string.h" HAVE_STRERROR_R)
 check_symbol_exists(siginterrupt   "${CURL_INCLUDES}" HAVE_SIGINTERRUPT)
 check_symbol_exists(getaddrinfo    "${CURL_INCLUDES};stdlib.h;string.h" HAVE_GETADDRINFO)
+check_symbol_exists(getifaddrs     "${CURL_INCLUDES};stdlib.h" HAVE_GETIFADDRS)
 if(WIN32)
   set(HAVE_GETADDRINFO_THREADSAFE ${HAVE_GETADDRINFO})
 endif()

lib/curl_config.h.cmake

@@ -502,6 +502,9 @@
 /* Define to 1 if you have the strtoll function. */
 #cmakedefine HAVE_STRTOLL 1
 
+/* Define to 1 if you have the memrchr function. */
+#cmakedefine HAVE_MEMRCHR 1
+
 /* if struct sockaddr_storage is defined */
 #cmakedefine HAVE_STRUCT_SOCKADDR_STORAGE 1