/* 

 * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com)

 * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>

 *

 * 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 

 */

#include <pj/except.h>

#include <pj/os.h>

#include <pj/assert.h>

#include <pj/log.h>

#include <pj/errno.h>

#include <pj/string.h>

static long thread_local_id = -1;

#if defined(PJ_HAS_EXCEPTION_NAMES) && PJ_HAS_EXCEPTION_NAMES != 0

    static const char *exception_id_names[PJ_MAX_EXCEPTION_ID];

#else

    /*

     * Start from 1 (not 0)!!!

     * Exception 0 is reserved for normal path of setjmp()!!!

     */

    static int last_exception_id = 1;

#endif  /* PJ_HAS_EXCEPTION_NAMES */

#if !defined(PJ_EXCEPTION_USE_WIN32_SEH) || PJ_EXCEPTION_USE_WIN32_SEH==0

PJ_DEF(void) pj_throw_exception_(int exception_id)

{

    struct pj_exception_state_t *handler;

    handler = (struct pj_exception_state_t*) 

              pj_thread_local_get(thread_local_id);

    if (handler == NULL) {

        PJ_LOG(1,("except.c", "!!!FATAL: unhandled exception %s!\n", 

                   pj_exception_id_name(exception_id)));

        pj_assert(handler != NULL);

        /* This will crash the system! */

    }

    pj_pop_exception_handler_(handler);

    pj_longjmp(handler->state, exception_id);

}

static void exception_cleanup(void)

{

    if (thread_local_id != -1) {

        pj_thread_local_free(thread_local_id);

        thread_local_id = -1;

    }

#if defined(PJ_HAS_EXCEPTION_NAMES) && PJ_HAS_EXCEPTION_NAMES != 0

    {

        unsigned i;

        for (i=0; i<PJ_MAX_EXCEPTION_ID; ++i)

            exception_id_names[i] = NULL;

    }

#else

    last_exception_id = 1;

#endif

}

PJ_DEF(void) pj_push_exception_handler_(struct pj_exception_state_t *rec)

{

    struct pj_exception_state_t *parent_handler = NULL;

    if (thread_local_id == -1) {

        pj_thread_local_alloc(&thread_local_id);

        pj_assert(thread_local_id != -1);

        pj_atexit(&exception_cleanup);

    }

    parent_handler = (struct pj_exception_state_t *)

                      pj_thread_local_get(thread_local_id);

    rec->prev = parent_handler;

    pj_thread_local_set(thread_local_id, rec);

}

PJ_DEF(void) pj_pop_exception_handler_(struct pj_exception_state_t *rec)

{

    struct pj_exception_state_t *handler;

    handler = (struct pj_exception_state_t *)

              pj_thread_local_get(thread_local_id);

    if (handler && handler==rec) {

        pj_thread_local_set(thread_local_id, handler->prev);

    }

}

#endif

#if defined(PJ_HAS_EXCEPTION_NAMES) && PJ_HAS_EXCEPTION_NAMES != 0

PJ_DEF(pj_status_t) pj_exception_id_alloc( const char *name,

                                           pj_exception_id_t *id)

{

    unsigned i;

    pj_enter_critical_section();

    /*

     * Start from 1 (not 0)!!!

     * Exception 0 is reserved for normal path of setjmp()!!!

     */

    for (i=1; i<PJ_MAX_EXCEPTION_ID; ++i) {

        if (exception_id_names[i] == NULL) {

            exception_id_names[i] = name;

            *id = i;

            pj_leave_critical_section();

            return PJ_SUCCESS;

        }

    }

    pj_leave_critical_section();

    return PJ_ETOOMANY;

}

PJ_DEF(pj_status_t) pj_exception_id_free( pj_exception_id_t id )

{

    /*

     * Start from 1 (not 0)!!!

     * Exception 0 is reserved for normal path of setjmp()!!!

     */

    PJ_ASSERT_RETURN(id>0 && id<PJ_MAX_EXCEPTION_ID, PJ_EINVAL);

    pj_enter_critical_section();

    exception_id_names[id] = NULL;

    pj_leave_critical_section();

    return PJ_SUCCESS;

}

PJ_DEF(const char*) pj_exception_id_name(pj_exception_id_t id)

{

    static char unknown_name[32];

    /*

     * Start from 1 (not 0)!!!

     * Exception 0 is reserved for normal path of setjmp()!!!

     */

    PJ_ASSERT_RETURN(id>0 && id<PJ_MAX_EXCEPTION_ID, "<Invalid ID>");

    if (exception_id_names[id] == NULL) {

        pj_ansi_snprintf(unknown_name, sizeof(unknown_name), 

                         "exception %d", id);

        return unknown_name;

    }

    return exception_id_names[id];

}

#else   /* PJ_HAS_EXCEPTION_NAMES */

PJ_DEF(pj_status_t) pj_exception_id_alloc( const char *name,

                                           pj_exception_id_t *id)

{

    PJ_ASSERT_RETURN(last_exception_id < PJ_MAX_EXCEPTION_ID-1, PJ_ETOOMANY);

    *id = last_exception_id++;

    return PJ_SUCCESS;

}

PJ_DEF(pj_status_t) pj_exception_id_free( pj_exception_id_t id )

{

    return PJ_SUCCESS;

}

PJ_DEF(const char*) pj_exception_id_name(pj_exception_id_t id)

{

    return "";

}

#endif  /* PJ_HAS_EXCEPTION_NAMES */