Check for vasprintf() and add a replacement if it wasn't found.

configure

@@ -4,6 +4,7 @@
 # Ensure that we do not inherit these from env
 STRLCPY=
 STRLCAT=
+VASPRINTF=
 OS=
 BUILD=
 HOST=
@@ -275,6 +276,29 @@ if [ -n "$BUILD_PIE" ]; then
 	check_compiler_flag pie "" PROG_LDFLAGS
 fi
 
+#
+# Check for vasprintf().
+#
+printf "Checking for vasprintf() ... "
+cat <<EOF >_vasprintf.c
+#define _GNU_SOURCE
+#include <stdio.h>
+int main(void) {
+	vasprintf(NULL, NULL, NULL);
+	return 0;
+}
+EOF
+if $XCC _vasprintf.c -o _vasprintf 2>/dev/null; then
+	VASPRINTF=yes
+else
+	VASPRINTF=no
+fi
+echo "$VASPRINTF."
+rm -f _vasprint.c _vasprintf
+if [ "$VASPRINTF" = "yes" ]; then
+	echo "CPPFLAGS +=	-DHAVE_VASPRINTF" >> $CONFIG_MK
+fi
+
 #
 # Check for strlcpy().
 #
@@ -298,6 +322,7 @@ rm -f _strlcpy.c _strlcpy
 if [ "$STRLCPY" = no ]; then
 	echo "COMPAT_SRCS +=	compat/strlcpy.o" >>$CONFIG_MK
 	echo "#include \"strlcpy.h\"" >>$CONFIG_H
+else
 	echo "CPPFLAGS +=	-DHAVE_STRLCPY" >> $CONFIG_MK
 fi
 
@@ -323,6 +348,7 @@ rm -f _strlcat.c _strlcat
 if [ "$STRLCAT" = no ]; then
 	echo "COMPAT_SRCS +=	compat/strlcat.o" >>$CONFIG_MK
 	echo "#include \"strlcat.h\"" >>$CONFIG_H
+else
 	echo "CPPFLAGS +=	-DHAVE_STRLCAT" >>$CONFIG_MK
 fi
 

lib/util.c

@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 2008-2010 Juan Romero Pardines.
+ * Copyright (c) 2008-2011 Juan Romero Pardines.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -45,7 +45,6 @@
  * @brief Utility routines
  * @defgroup util Utility functions
  */
-
 static const char *rootdir;
 static const char *cachedir;
 static int flags;
@@ -493,6 +492,7 @@ xbps_get_flags(void)
 	return flags;
 }
 
+#ifdef HAVE_VASPRINTF
 char *
 xbps_xasprintf(const char *fmt, ...)
 {
@@ -500,9 +500,38 @@ xbps_xasprintf(const char *fmt, ...)
 	char *buf;
 
 	va_start(ap, fmt);
-	if (vasprintf(&buf, fmt, ap) == -1)
+	if (vasprintf(&buf, fmt, ap) == -1) {
+		va_end(ap);
 		return NULL;
+	}
 	va_end(ap);
 
 	return buf;
 }
+#else
+char *
+xbps_xasprintf(const char *fmt, ...)
+{
+	va_list ap, aq;
+	size_t len;
+	int res;
+	char *buf;
+
+	va_start(aq, fmt);
+	va_copy(ap, aq);
+	len = vsnprintf(NULL, 0, fmt, aq) + 1;
+	if ((buf = malloc(len)) == NULL) {
+		va_end(ap);
+		return NULL;
+	}
+
+	va_start(ap, fmt);
+	res = vsnprintf(buf, len, fmt, ap);
+	if (res < 0 || res >= (int)len) {
+		free(buf);
+		return NULL;
+	}
+
+	return buf;
+}
+#endif /* !HAVE_VASPRINTF */