Check for functions instead of OS

Author: mkochenough

configure.ac

@@ -5,7 +5,7 @@ AC_PROG_CXX
 AC_PROG_LN_S
 AC_PROG_RANLIB
 AC_CHECK_HEADER_STDBOOL
-AC_CHECK_FUNCS([inet_ntoa memmove strchr strdup strstr strtoul])
+AC_CHECK_FUNCS([inet_ntoa memmove strnchr strdup strnstr strtoul])
 AC_CHECK_HEADERS([arpa/inet.h netinet/in.h])
 AC_FUNC_MALLOC
 AC_FUNC_REALLOC

src/util.cc

@@ -1,9 +1,9 @@
 #include "util.h"
 
-#ifndef __APPLE__
-
 #include <string.h>
 
+#ifndef HAVE_STRNCHR
+
 const char* strnchr(const char* str, size_t len, int character) {
   const char* end = str + len;
   char c = (char) character;
@@ -17,6 +17,10 @@ const char* strnchr(const char* str, size_t len, int character) {
   return NULL;
 }
 
+#endif /* HAVE_STRNCHR */
+
+#ifndef HAVE_STRNSTR
+
 const char* strnstr(const char* str, const char* find, size_t len)
 {
   char c, sc;
@@ -43,4 +47,4 @@ const char* strnstr(const char* str, const char* find, size_t len)
   return ((char*) str);
 }
 
-#endif /* __APPLE__ */
+#endif /* HAVE_STRNSTR */

src/util.h

@@ -1,13 +1,14 @@
 #ifndef __UTIL_H__
 #define __UTIL_H__
 
-#ifndef __APPLE__
-
 #include <stdlib.h>
 
+#ifndef HAVE_STRNCHR
 const char* strnchr(const char* str, size_t len, int character);
-const char* strnstr(const char* str, const char* find, size_t len);
+#endif /* HAVE_STRNCHR */
 
-#endif /* __APPLE__ */
+#ifndef HAVE_STRNSTR
+const char* strnstr(const char* str, const char* find, size_t len);
+#endif /* HAVE_STRNSTR */
 
 #endif /* __UTIL_H__ */