Diff: flac/include/share/alloc.h

Revision:

0:ee40da884cfc

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flac/include/share/alloc.h	Fri Oct 16 04:28:07 2015 +0000
@@ -0,0 +1,209 @@
+/* alloc - Convenience routines for safely allocating memory
+ * Copyright (C) 2007-2009  Josh Coalson
+ * Copyright (C) 2011-2014  Xiph.Org Foundation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - 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.
+ *
+ * - Neither the name of the Xiph.org Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``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 FOUNDATION OR
+ * CONTRIBUTORS 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.
+ */
+
+#ifndef FLAC__SHARE__ALLOC_H
+#define FLAC__SHARE__ALLOC_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+/* WATCHOUT: for c++ you may have to #define __STDC_LIMIT_MACROS 1 real early
+ * before #including this file,  otherwise SIZE_MAX might not be defined
+ */
+
+#include <limits.h> /* for SIZE_MAX */
+#if HAVE_STDINT_H
+#include <stdint.h> /* for SIZE_MAX in case limits.h didn't get it */
+#endif
+#include <stdlib.h> /* for size_t, malloc(), etc */
+#include "share/compat.h"
+
+#ifndef SIZE_MAX
+# ifndef SIZE_T_MAX
+#  ifdef _MSC_VER
+#   ifdef _WIN64
+#    define SIZE_T_MAX 0xffffffffffffffffui64
+#   else
+#    define SIZE_T_MAX 0xffffffff
+#   endif
+#  else
+#   error
+#  endif
+# endif
+# define SIZE_MAX SIZE_T_MAX
+#endif
+
+/* avoid malloc()ing 0 bytes, see:
+ * https://www.securecoding.cert.org/confluence/display/seccode/MEM04-A.+Do+not+make+assumptions+about+the+result+of+allocating+0+bytes?focusedCommentId=5407003
+*/
+static inline void *safe_malloc_(size_t size)
+{
+	/* malloc(0) is undefined; FLAC src convention is to always allocate */
+	if(!size)
+		size++;
+	return malloc(size);
+}
+
+static inline void *safe_calloc_(size_t nmemb, size_t size)
+{
+	if(!nmemb || !size)
+		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
+	return calloc(nmemb, size);
+}
+
+/*@@@@ there's probably a better way to prevent overflows when allocating untrusted sums but this works for now */
+
+static inline void *safe_malloc_add_2op_(size_t size1, size_t size2)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	return safe_malloc_(size2);
+}
+
+static inline void *safe_malloc_add_3op_(size_t size1, size_t size2, size_t size3)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	size3 += size2;
+	if(size3 < size2)
+		return 0;
+	return safe_malloc_(size3);
+}
+
+static inline void *safe_malloc_add_4op_(size_t size1, size_t size2, size_t size3, size_t size4)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	size3 += size2;
+	if(size3 < size2)
+		return 0;
+	size4 += size3;
+	if(size4 < size3)
+		return 0;
+	return safe_malloc_(size4);
+}
+
+void *safe_malloc_mul_2op_(size_t size1, size_t size2) ;
+
+static inline void *safe_malloc_mul_3op_(size_t size1, size_t size2, size_t size3)
+{
+	if(!size1 || !size2 || !size3)
+		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
+	if(size1 > SIZE_MAX / size2)
+		return 0;
+	size1 *= size2;
+	if(size1 > SIZE_MAX / size3)
+		return 0;
+	return malloc(size1*size3);
+}
+
+/* size1*size2 + size3 */
+static inline void *safe_malloc_mul2add_(size_t size1, size_t size2, size_t size3)
+{
+	if(!size1 || !size2)
+		return safe_malloc_(size3);
+	if(size1 > SIZE_MAX / size2)
+		return 0;
+	return safe_malloc_add_2op_(size1*size2, size3);
+}
+
+/* size1 * (size2 + size3) */
+static inline void *safe_malloc_muladd2_(size_t size1, size_t size2, size_t size3)
+{
+	if(!size1 || (!size2 && !size3))
+		return malloc(1); /* malloc(0) is undefined; FLAC src convention is to always allocate */
+	size2 += size3;
+	if(size2 < size3)
+		return 0;
+	if(size1 > SIZE_MAX / size2)
+		return 0;
+	return malloc(size1*size2);
+}
+
+static inline void *safe_realloc_add_2op_(void *ptr, size_t size1, size_t size2)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	return realloc(ptr, size2);
+}
+
+static inline void *safe_realloc_add_3op_(void *ptr, size_t size1, size_t size2, size_t size3)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	size3 += size2;
+	if(size3 < size2)
+		return 0;
+	return realloc(ptr, size3);
+}
+
+static inline void *safe_realloc_add_4op_(void *ptr, size_t size1, size_t size2, size_t size3, size_t size4)
+{
+	size2 += size1;
+	if(size2 < size1)
+		return 0;
+	size3 += size2;
+	if(size3 < size2)
+		return 0;
+	size4 += size3;
+	if(size4 < size3)
+		return 0;
+	return realloc(ptr, size4);
+}
+
+static inline void *safe_realloc_mul_2op_(void *ptr, size_t size1, size_t size2)
+{
+	if(!size1 || !size2)
+		return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
+	if(size1 > SIZE_MAX / size2)
+		return 0;
+	return realloc(ptr, size1*size2);
+}
+
+/* size1 * (size2 + size3) */
+static inline void *safe_realloc_muladd2_(void *ptr, size_t size1, size_t size2, size_t size3)
+{
+	if(!size1 || (!size2 && !size3))
+		return realloc(ptr, 0); /* preserve POSIX realloc(ptr, 0) semantics */
+	size2 += size3;
+	if(size2 < size3)
+		return 0;
+	return safe_realloc_mul_2op_(ptr, size1, size2);
+}
+
+#endif