Add fpurge function

Makefile

@@ -27,6 +27,7 @@ LIB_SRCS := \
 	err.c \
 	fgetln.c \
 	flopen.c \
+	fpurge.c \
 	getpeereid.c \
 	heapsort.c \
 	merge.c \

Versions

@@ -86,5 +86,7 @@ LIBBSD_0.3 {
     mergesort;
     radixsort;
     sradixsort;
+
+    fpurge;
 } LIBBSD_0.2;
 

include/bsd/stdio.h

@@ -1,5 +1,5 @@
 /*
- * Copyright © 2004, 2005, 2009 Guillem Jover
+ * Copyright © 2004, 2005, 2009, 2011 Guillem Jover
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -40,6 +40,8 @@ __BEGIN_DECLS
 const char *fmtcheck(const char *, const char *);
 
 char *fgetln(FILE *fp, size_t *lenp);
+
+int fpurge(FILE *fp);
 __END_DECLS
 
 #endif

src/fpurge.c

@@ -0,0 +1,68 @@
+/*
+ * Copyright © 2011 Guillem Jover
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
+ * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#define _GNU_SOURCE 1
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdio_ext.h>
+
+#ifdef __GLIBC__
+int
+fpurge(FILE *fp)
+{
+	if (fp == NULL || fileno(fp) < 0) {
+		errno = EBADF;
+		return EOF;
+	}
+
+	__fpurge(fp);
+
+	return 0;
+}
+#else
+#error "Function fpurge() needs to be ported."
+#endif
+
+#ifdef TEST
+int
+main()
+{
+	static FILE fp_bad;
+	FILE *fp;
+
+	if (fpurge(&fp_bad) == 0)
+		return 1;
+
+	fp = fopen("/dev/zero", "r");
+	if (fpurge(fp) < 0)
+		return 1;
+
+	fclose(fp);
+
+	return 0;
+}
+#endif