Restructuring of code

code/external/libsmacker/smk_malloc.h

@@ -0,0 +1,68 @@
+/*
+	libsmacker - A C library for decoding .smk Smacker Video files
+	Copyright (C) 2012-2013 Greg Kennedy
+
+	See smacker.h for more information.
+
+	smk_malloc.h
+		"Safe" implementations of malloc and free.
+*/
+
+#ifndef SMK_MALLOC_H
+#define SMK_MALLOC_H
+
+#include <stdlib.h>
+#include <stdio.h>
+/* for memset */
+#include <string.h>
+
+/* "safe" null check:
+	branches to an error block if pointer is null */
+#define smk_null_check(p) \
+{ \
+	if (!p) \
+	{ \
+		fprintf(stderr,"libsmacker::smk_null_check(" #p "): ERROR: NULL POINTER at line %lu, file %s\n", (unsigned long)__LINE__, __FILE__); \
+		goto error; \
+	} \
+}
+
+/*
+	Safe free: attempts to prevent double-free by setting pointer to NULL.
+		Warns on attempts to free a NULL pointer.
+*/
+#define smk_free(p) \
+{ \
+	if (p) \
+	{ \
+		free(p); \
+		p = NULL; \
+	} \
+/*	else \
+	{ \
+		fprintf(stderr,"libsmacker::smk_free(" #p ") - Warning: attempt to free NULL pointer (file: %s, line: %lu)\n", __FILE__, (unsigned long)__LINE__); \
+	} */ \
+}
+
+/*
+	Safe malloc: exits if malloc() returns NULL.
+	Ideally, one should not exit() in a library. However, if you cannot
+		malloc(), you probably have bigger problems.
+*/
+#define smk_malloc(p,x) \
+{ \
+	if (p) \
+	{ \
+		fprintf(stderr,"libsmacker::smk_malloc(" #p ",%lu) - Warning: freeing non-NULL pointer before malloc (file: %s, line: %lu)\n", (unsigned long) x, __FILE__, (unsigned long)__LINE__); \
+		smk_free(p); \
+	} \
+	p = malloc(x); \
+	if (!p) \
+	{ \
+		fprintf(stderr,"libsmacker::smk_malloc(" #p ",%lu) - ERROR: malloc() returned NULL (file: %s, line: %lu)\n", (unsigned long) x,  __FILE__, (unsigned long)__LINE__); \
+		exit(EXIT_FAILURE); \
+	} \
+	memset(p,0,x); \
+}
+
+#endif