guacamole-spice-protocol/src/libguac/error.c

/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is libguac.
 *
 * The Initial Developer of the Original Code is
 * Michael Jumper.
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

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

#ifdef HAVE_LIBPTHREAD
#include <pthread.h>
#endif

#include "error.h"

/* Error strings */

const char* __GUAC_STATUS_SUCCESS_STR        = "Success";
const char* __GUAC_STATUS_NO_MEMORY_STR      = "Insufficient memory";
const char* __GUAC_STATUS_NO_INPUT_STR       = "End of input stream";
const char* __GUAC_STATUS_INPUT_TIMEOUT_STR  = "Read timeout";
const char* __GUAC_STATUS_OUTPUT_ERROR_STR   = "Output error";
const char* __GUAC_STATUS_BAD_ARGUMENT_STR   = "Invalid argument";
const char* __GUAC_STATUS_BAD_STATE_STR      = "Illegal state";
const char* __GUAC_STATUS_INVALID_STATUS_STR = "UNKNOWN STATUS CODE";


const char* guac_status_string(guac_status status) {

    switch (status) {

        /* No error */
		case GUAC_STATUS_SUCCESS:
            return __GUAC_STATUS_SUCCESS_STR;

        /* Out of memory */
		case GUAC_STATUS_NO_MEMORY:
            return __GUAC_STATUS_NO_MEMORY_STR;

        /* End of input */
		case GUAC_STATUS_NO_INPUT:
            return __GUAC_STATUS_NO_INPUT_STR;

        /* Input timeout */
		case GUAC_STATUS_INPUT_TIMEOUT:
            return __GUAC_STATUS_INPUT_TIMEOUT_STR;

        /* Further information in errno */
		case GUAC_STATUS_SEE_ERRNO:
            return strerror(errno);

        /* Output error */
		case GUAC_STATUS_OUTPUT_ERROR:
            return __GUAC_STATUS_OUTPUT_ERROR_STR;

        /* Invalid argument */
		case GUAC_STATUS_BAD_ARGUMENT:
            return __GUAC_STATUS_BAD_ARGUMENT_STR;

        /* Illegal state */
		case GUAC_STATUS_BAD_STATE:
            return __GUAC_STATUS_BAD_STATE_STR;

        default:
            return __GUAC_STATUS_INVALID_STATUS_STR;

    }

}

#ifdef HAVE_LIBPTHREAD

/* PThread implementation of __guac_error */

static pthread_key_t  __guac_error_key;
static pthread_once_t __guac_error_key_init = PTHREAD_ONCE_INIT;

static pthread_key_t  __guac_error_message_key;
static pthread_once_t __guac_error_message_key_init = PTHREAD_ONCE_INIT;

static void __guac_free_pointer(void* pointer) {

    /* Free memory allocated to status variable */
    free(pointer);

}

static void __guac_alloc_error_key() {

    /* Create key, destroy any allocated variable on thread exit */
    pthread_key_create(&__guac_error_key, __guac_free_pointer);

}

static void __guac_alloc_error_message_key() {

    /* Create key, destroy any allocated variable on thread exit */
    pthread_key_create(&__guac_error_message_key, __guac_free_pointer);

}

guac_status* __guac_error() {

    /* Pointer for thread-local data */
    guac_status* status;

    /* Init error key, if not already initialized */
    pthread_once(&__guac_error_key_init, __guac_alloc_error_key);

    /* Retrieve thread-local status variable */
    status = (guac_status*) pthread_getspecific(__guac_error_key);

    /* Allocate thread-local status variable if not already allocated */
    if (status == NULL) {
        status = malloc(sizeof(guac_status));
        pthread_setspecific(__guac_error_key, status);
    }

    return status;

}

const char** __guac_error_message() {

    /* Pointer for thread-local data */
    const char** message;

    /* Init error message key, if not already initialized */
    pthread_once(
        &__guac_error_message_key_init,
        __guac_alloc_error_message_key
    );

    /* Retrieve thread-local message variable */
    message = (const char**) pthread_getspecific(__guac_error_message_key);

    /* Allocate thread-local message variable if not already allocated */
    if (message == NULL) {
        message = malloc(sizeof(const char*));
        pthread_setspecific(__guac_error_message_key, message);
    }

    return message;

}

#else

/* Default (not-threadsafe) implementation */
static guac_status __guac_error_unsafe_storage;
static const char** __guac_error_message_unsafe_storage;

guac_status* __guac_error() {
    return &__guac_error_unsafe_storage;
}

const char** __guac_error_message() {
    return &__guac_error_message_unsafe_storage;
}

/* Warn about threadsafety */
#warn No threadsafe implementation of __guac_error exists for your platform, so a default non-threadsafe implementation has been used instead. This may lead to incorrect status codes being reported for failures. Please consider adding support for your platform, or filing a bug report with the Guacamole project.

#endif