[vlc-devel] [PATCH] configure: check if if_nametoindex is available on Windows

[Steve Lhomme]

It may link with iphlpapi but be forbidden in UWP.

This test relies on the fact that -Werror-implicit-function-declaration works
in the compiler. And that's why it's done after it's enabled.
---
 configure.ac         | 18 ++++++++++++++++++
 include/vlc_fixups.h |  4 ++++
 2 files changed, 22 insertions(+)

diff --git a/configure.ac b/configure.ac
index d75b2fd9921..e1d535f6f06 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1049,6 +1049,24 @@ AX_APPEND_COMPILE_FLAGS([-Wall -Wextra -Wsign-compare -Wundef -Wpointer-arith -W
 AX_APPEND_COMPILE_FLAGS([-Wbad-function-cast -Wwrite-strings -Wmissing-prototypes -Werror-implicit-function-declaration -Winit-self -Wlogical-op -Wshadow=local -Wmultistatement-macros], [CFLAGS])
 AX_APPEND_COMPILE_FLAGS([-pipe], [CFLAGS])
 
+dnl UWP forbidden checks
+AS_IF([test "${SYS}" = "mingw32"], [
+  AC_MSG_CHECKING(for if_nametoindex availability)
+  AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
+      [[#include <windows.h>
+        #include <iphlpapi.h>
+        static void test (void) {
+          if_nametoindex(NULL);
+        }
+      ]],[[;]])
+    ],[
+      AC_MSG_RESULT([present])
+      AC_DEFINE([HAVE_IF_NAMETOINDEX], [1], [Define to 1 if you have if_nametoindex function])
+    ],[
+      AC_MSG_RESULT([not present])
+    ])
+])
+
 dnl
 dnl  Debugging mode
 dnl
diff --git a/include/vlc_fixups.h b/include/vlc_fixups.h
index 25c7de473e6..42d5b31661f 100644
--- a/include/vlc_fixups.h
+++ b/include/vlc_fixups.h
@@ -454,6 +454,10 @@ struct msghdr
     size_t        msg_controllen;
     int           msg_flags;
 };
+
+# ifndef HAVE_IF_NAMETOINDEX
+#  define if_nametoindex(name)  atoi(name)
+# endif
 #endif
 
 #ifdef _NEWLIB_VERSION
-- 
2.17.1