/*
 * libid3tag - ID3 tag manipulation library
 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * $Id: debug.c,v 1.8 2004/01/23 09:41:32 rob Exp $
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include "global.h"

#undef malloc
#undef calloc
#undef realloc
#undef free

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "debug.h"

#if defined(DEBUG)

# define DEBUG_MAGIC  0xdeadbeefL

struct debug {
	char const *file;
	unsigned int line;
	size_t size;
	struct debug *next;
	struct debug *prev;
	long int magic;
};

static struct debug *allocated;
static int registered;

static void
check(void)
{
	struct debug *debug;

	for (debug = allocated; debug; debug = debug->next) {
		if (debug->magic != DEBUG_MAGIC) {
			fprintf(stderr, "memory corruption\n");
			break;
		}

		fprintf(stderr, "%s:%u: leaked %lu bytes\n",
			debug->file, debug->line, debug->size);
	}
}

void *
id3_debug_malloc(size_t size, char const *file, unsigned int line)
{
	struct debug *debug;

	if (!registered) {
		atexit(check);
		registered = 1;
	}

	if (size == 0)
		fprintf(stderr, "%s:%u: malloc(0)\n", file, line);

	debug = malloc(sizeof(*debug) + size);
	if (debug == 0) {
		fprintf(stderr, "%s:%u: malloc(%lu) failed\n", file, line,
			size);
		return 0;
	}

	debug->magic = DEBUG_MAGIC;

	debug->file = file;
	debug->line = line;
	debug->size = size;

	debug->next = allocated;
	debug->prev = 0;

	if (allocated)
		allocated->prev = debug;

	allocated = debug;

	return ++debug;
}

void *
id3_debug_calloc(size_t nmemb, size_t size,
		 char const *file, unsigned int line)
{
	void *ptr;

	ptr = id3_debug_malloc(nmemb * size, file, line);
	if (ptr)
		memset(ptr, 0, nmemb * size);

	return ptr;
}

void *
id3_debug_realloc(void *ptr, size_t size,
		  char const *file, unsigned int line)
{
	struct debug *debug, *new;

	if (size == 0) {
		id3_debug_free(ptr, file, line);
		return 0;
	}

	if (ptr == 0)
		return id3_debug_malloc(size, file, line);

	debug = ptr;
	--debug;

	if (debug->magic != DEBUG_MAGIC) {
		fprintf(stderr, "%s:%u: realloc(%p, %lu) memory not allocated\n",
			file, line, ptr, size);
		return 0;
	}

	new = realloc(debug, sizeof(*debug) + size);
	if (new == 0) {
		fprintf(stderr, "%s:%u: realloc(%p, %lu) failed\n",
			file, line, ptr, size);
		return 0;
	}

	if (allocated == debug)
		allocated = new;

	debug = new;

	debug->file = file;
	debug->line = line;
	debug->size = size;

	if (debug->next)
		debug->next->prev = debug;
	if (debug->prev)
		debug->prev->next = debug;

	return ++debug;
}

void
id3_debug_free(void *ptr, char const *file, unsigned int line)
{
	struct debug *debug;

	if (ptr == 0) {
		fprintf(stderr, "%s:%u: free(0)\n", file, line);
		return;
	}

	debug = ptr;
	--debug;

	if (debug->magic != DEBUG_MAGIC) {
		fprintf(stderr, "%s:%u: free(%p) memory not allocated\n",
			file, line, ptr);
		return;
	}

	debug->magic = 0;

	if (debug->next)
		debug->next->prev = debug->prev;
	if (debug->prev)
		debug->prev->next = debug->next;

	if (allocated == debug)
		allocated = debug->next;

	free(debug);
}

void *
id3_debug_release(void *ptr, char const *file, unsigned int line)
{
	struct debug *debug;

	if (ptr == 0)
		return 0;

	debug = ptr;
	--debug;

	if (debug->magic != DEBUG_MAGIC) {
		fprintf(stderr, "%s:%u: release(%p) memory not allocated\n",
			file, line, ptr);
		return ptr;
	}

	if (debug->next)
		debug->next->prev = debug->prev;
	if (debug->prev)
		debug->prev->next = debug->next;

	if (allocated == debug)
		allocated = debug->next;

	memmove(debug, debug + 1, debug->size);

	return debug;
}

#endif