/*
 *  Window Maker miscelaneous function library
 *
 *  Copyright (c) 1997-2003 Alfredo K. Kojima
 *
 *  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., 51 Franklin St, Fifth Floor, Boston,
 *  MA 02110-1301, USA.
 */

#include "wconfig.h"
#include "WUtil.h"

#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include <signal.h>

#ifdef HAVE_STDNORETURN
#include <stdnoreturn.h>
#endif

#ifdef USE_BOEHM_GC
#ifndef GC_DEBUG
#define GC_DEBUG
#endif /* !GC_DEBUG */
#include <gc/gc.h>
#endif /* USE_BOEHM_GC */

#ifndef False
# define False 0
#endif
#ifndef True
# define True 1
#endif

static void defaultHandler(int bla)
{
	if (bla)
		kill(getpid(), SIGABRT);
	else
		exit(1);
}

static waborthandler *aborthandler = defaultHandler;

static inline noreturn void wAbort(int bla)
{
	(*aborthandler)(bla);
	exit(-1);
}

waborthandler *wsetabort(waborthandler * handler)
{
	waborthandler *old = aborthandler;

	aborthandler = handler;

	return old;
}

static int Aborting = 0;	/* if we're in the middle of an emergency exit */

static WMHashTable *table = NULL;

void *wmalloc(size_t size)
{
	void *tmp;

	assert(size > 0);

#ifdef USE_BOEHM_GC
	tmp = GC_MALLOC(size);
#else
	tmp = malloc(size);
#endif
	if (tmp == NULL) {
		wwarning("malloc() failed. Retrying after 2s.");
		sleep(2);
#ifdef USE_BOEHM_GC
		tmp = GC_MALLOC(size);
#else
		tmp = malloc(size);
#endif
		if (tmp == NULL) {
			if (Aborting) {
				fputs("Really Bad Error: recursive malloc() failure.", stderr);
				exit(-1);
			} else {
				wfatal("virtual memory exhausted");
				Aborting = 1;
				wAbort(False);
			}
		}
	}
	if (tmp != NULL)
		memset(tmp, 0, size);
	return tmp;
}

void *wrealloc(void *ptr, size_t newsize)
{
	void *nptr;

	if (!ptr) {
		nptr = wmalloc(newsize);
	} else if (newsize == 0) {
		wfree(ptr);
		nptr = NULL;
	} else {
#ifdef USE_BOEHM_GC
		nptr = GC_REALLOC(ptr, newsize);
#else
		nptr = realloc(ptr, newsize);
#endif
		if (nptr == NULL) {
			wwarning("realloc() failed. Retrying after 2s.");
			sleep(2);
#ifdef USE_BOEHM_GC
			nptr = GC_REALLOC(ptr, newsize);
#else
			nptr = realloc(ptr, newsize);
#endif
			if (nptr == NULL) {
				if (Aborting) {
					fputs("Really Bad Error: recursive realloc() failure.", stderr);
					exit(-1);
				} else {
					wfatal("virtual memory exhausted");
					Aborting = 1;
					wAbort(False);
				}
			}
		}
	}
	return nptr;
}

void *wretain(void *ptr)
{
	int *refcount;

	if (!table) {
		table = WMCreateHashTable(WMIntHashCallbacks);
	}

	refcount = WMHashGet(table, ptr);
	if (!refcount) {
		refcount = wmalloc(sizeof(int));
		*refcount = 1;
		WMHashInsert(table, ptr, refcount);
#ifdef VERBOSE
		printf("== %i (%p)\n", *refcount, ptr);
#endif
	} else {
		(*refcount)++;
#ifdef VERBOSE
		printf("+ %i (%p)\n", *refcount, ptr);
#endif
	}

	return ptr;
}

void wfree(void *ptr)
{
	if (ptr)
#ifdef USE_BOEHM_GC
		/* This should eventually be removed, once the criss-cross
		 * of wmalloc()d memory being free()d, malloc()d memory being
		 * wfree()d, various misuses of calling wfree() on objects
		 * allocated by libc malloc() and calling libc free() on
		 * objects allocated by Boehm GC (think external libraries)
		 * is cleaned up.
		 */
		if (GC_base(ptr) != 0)
			GC_FREE(ptr);
		else
			free(ptr);
#else
		free(ptr);
#endif
	ptr = NULL;
}

void wrelease(void *ptr)
{
	int *refcount;

	refcount = WMHashGet(table, ptr);
	if (!refcount) {
		wwarning("trying to release unexisting data %p", ptr);
	} else {
		(*refcount)--;
		if (*refcount < 1) {
#ifdef VERBOSE
			printf("RELEASING %p\n", ptr);
#endif
			WMHashRemove(table, ptr);
			wfree(refcount);
			wfree(ptr);
		}
#ifdef VERBOSE
		else {
			printf("- %i (%p)\n", *refcount, ptr);
		}
#endif
	}
}