/*
 * Copyright (C) 2012 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * $Id$
 */

#include "ipf.h"

#define EMM_MAGIC       0x9d7adba3

static  int     mutex_debug = 0;
static  FILE    *mutex_file = NULL;
static  int     initcount = 0;

void
eMmutex_enter(eMmutex_t *mtx, char *file, int line)
{
        if (mutex_debug & 2)
                fprintf(mutex_file, "%s:%d:eMmutex_enter(%s)\n", file, line,
                       mtx->eMm_owner);
        if (mtx->eMm_magic != EMM_MAGIC) {
                fprintf(stderr, "%s:eMmutex_enter(%p): bad magic: %#x\n",
                        mtx->eMm_owner, mtx, mtx->eMm_magic);
                abort();
        }
        if (mtx->eMm_held != 0) {
                fprintf(stderr, "%s:eMmutex_enter(%p): already locked: %d\n",
                        mtx->eMm_owner, mtx, mtx->eMm_held);
                abort();
        }
        mtx->eMm_held++;
        mtx->eMm_heldin = file;
        mtx->eMm_heldat = line;
}


void
eMmutex_exit(eMmutex_t *mtx, char *file, int line)
{
        if (mutex_debug & 2)
                fprintf(mutex_file, "%s:%d:eMmutex_exit(%s)\n", file, line,
                       mtx->eMm_owner);
        if (mtx->eMm_magic != EMM_MAGIC) {
                fprintf(stderr, "%s:eMmutex_exit(%p): bad magic: %#x\n",
                        mtx->eMm_owner, mtx, mtx->eMm_magic);
                abort();
        }
        if (mtx->eMm_held != 1) {
                fprintf(stderr, "%s:eMmutex_exit(%p): not locked: %d\n",
                        mtx->eMm_owner, mtx, mtx->eMm_held);
                abort();
        }
        mtx->eMm_held--;
        mtx->eMm_heldin = NULL;
        mtx->eMm_heldat = 0;
}


void
eMmutex_init(eMmutex_t *mtx, char *who, char *file, int line)
{
        if (mutex_file == NULL && mutex_debug)
                mutex_file = fopen("ipf_mutex_log", "w");
        if (mutex_debug & 1)
                fprintf(mutex_file, "%s:%d:eMmutex_init(%p,%s)\n",
                        file, line, mtx, who);
        if (mtx->eMm_magic == EMM_MAGIC) {      /* safe bet ? */
                fprintf(stderr,
                        "%s:eMmutex_init(%p): already initialised?: %#x\n",
                        mtx->eMm_owner, mtx, mtx->eMm_magic);
                abort();
        }
        mtx->eMm_magic = EMM_MAGIC;
        mtx->eMm_held = 0;
        if (who != NULL)
                mtx->eMm_owner = strdup(who);
        else
                mtx->eMm_owner = NULL;
        initcount++;
}


void
eMmutex_destroy(eMmutex_t *mtx, char *file, int line)
{
        if (mutex_debug & 1)
                fprintf(mutex_file,
                        "%s:%d:eMmutex_destroy(%p,%s)\n", file, line,
                        mtx, mtx->eMm_owner);
        if (mtx->eMm_magic != EMM_MAGIC) {
                fprintf(stderr, "%s:eMmutex_destroy(%p): bad magic: %#x\n",
                        mtx->eMm_owner, mtx, mtx->eMm_magic);
                abort();
        }
        if (mtx->eMm_held != 0) {
                fprintf(stderr,
                        "%s:eMmutex_enter(%p): still locked: %d\n",
                        mtx->eMm_owner, mtx, mtx->eMm_held);
                abort();
        }
        if (mtx->eMm_owner != NULL)
                free(mtx->eMm_owner);
        memset(mtx, 0xa5, sizeof(*mtx));
        initcount--;
}


void
ipf_mutex_clean(void)
{
        if (initcount != 0) {
                if (mutex_file)
                        fprintf(mutex_file, "initcount %d\n", initcount);
                abort();
        }
}