macOS: fix target detection more

Now SCDynamicStoreCopyProxies is called (and the required frameworks are
linked in) on all versions of macOS and only on macOS. Fixes crash due
to undefined symbol when built with the macOS 10.11 SDK or earlier.

CURL_OSX_CALL_COPYPROXIES is renamed to CURL_MACOS_CALL_COPYPROXIES and
is now only defined when SCDynamicStoreCopyProxies will actually be
called. Previously, it was defined when ENABLE_IPV6 was not defined but
SCDynamicStoreCopyProxies is not called in that case.

TARGET_OS_OSX is only defined in the macOS 10.12 SDK and later and only
when dynamic targets are enabled. TARGET_OS_MAC is always defined but
means any Mac OS or derivative including macOS, iOS, tvOS, and watchOS.
TARGET_OS_IPHONE means any Darwin OS other than macOS.

Follow-up to c73b2f82

Fixes #11502
Closes #11516

lib/curl_setup.h

@@ -258,8 +258,9 @@
 #if defined(__APPLE__) && !defined(USE_ARES)
 #include <TargetConditionals.h>
 #define USE_RESOLVE_ON_IPS 1
-#  if !defined(TARGET_OS_OSX) || TARGET_OS_OSX
-#    define CURL_OSX_CALL_COPYPROXIES 1
+#  if TARGET_OS_MAC && !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) && \
+     defined(ENABLE_IPV6)
+#    define CURL_MACOS_CALL_COPYPROXIES 1
 #  endif
 #endif
 

lib/macos.c

@@ -24,21 +24,16 @@
 
 #include "curl_setup.h"
 
-#if defined(__APPLE__)
-
-#if !defined(TARGET_OS_OSX) || TARGET_OS_OSX
+#ifdef CURL_MACOS_CALL_COPYPROXIES
 
 #include <curl/curl.h>
 
 #include "macos.h"
 
-#if defined(ENABLE_IPV6) && defined(CURL_OSX_CALL_COPYPROXIES)
 #include <SystemConfiguration/SCDynamicStoreCopySpecific.h>
-#endif
 
 CURLcode Curl_macos_init(void)
 {
-#if defined(ENABLE_IPV6) && defined(CURL_OSX_CALL_COPYPROXIES)
   {
     /*
      * The automagic conversion from IPv4 literals to IPv6 literals only
@@ -46,17 +41,15 @@ CURLcode Curl_macos_init(void)
      * first. As Curl currently doesn't support system-wide HTTP proxies, we
      * therefore don't use any value this function might return.
      *
-     * This function is only available on a macOS and is not needed for
-     * IPv4-only builds, hence the conditions above.
+     * This function is only available on macOS and is not needed for
+     * IPv4-only builds, hence the conditions for defining
+     * CURL_MACOS_CALL_COPYPROXIES in curl_setup.h.
      */
     CFDictionaryRef dict = SCDynamicStoreCopyProxies(NULL);
     if(dict)
       CFRelease(dict);
   }
-#endif
   return CURLE_OK;
 }
 
-#endif /* TARGET_OS_OSX */
-
-#endif /* __APPLE__ */
+#endif

lib/macos.h

@@ -23,9 +23,10 @@
  * SPDX-License-Identifier: curl
  *
  ***************************************************************************/
+
 #include "curl_setup.h"
 
-#if defined(__APPLE__) && (!defined(TARGET_OS_OSX) || TARGET_OS_OSX)
+#ifdef CURL_MACOS_CALL_COPYPROXIES
 
 CURLcode Curl_macos_init(void);
 

m4/curl-sysconfig.m4

@@ -30,10 +30,10 @@ case $host_os in
       AC_LANG_PROGRAM([[
 #include <TargetConditionals.h>
       ]],[[
-#if (TARGET_OS_OSX)
+#if TARGET_OS_MAC && !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE)
       return 0;
 #else
-#error Not a macOS
+#error Not macOS
 #endif
       ]])
     ],[