/*

 * BSD LICENSE

 *

 * Copyright(c) 2014-2020 Intel Corporation. All rights reserved.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 *   * Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 *   * Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in

 *     the documentation and/or other materials provided with the

 *     distribution.

 *   * Neither the name of Intel Corporation nor the names of its

 *     contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.O

 *

 */

/**

 * @brief Library operations logger for info, warnings and errors.

 */

#include <stdio.h>

#include <stdlib.h>

#include <stdarg.h>

#include <string.h>

#include <unistd.h>

#include <errno.h>

#include "types.h"

#include "log.h"

/**

 * ---------------------------------------

 * Local data types

 * ---------------------------------------

 */

#define AP_BUFFER_SIZE 256

/**

 * ---------------------------------------

 * Local data structures

 * ---------------------------------------

 */

static int m_opt = 0;              /**< log options */

static int m_fd = -1;              /**< log file descriptor */

static void *m_context_log = NULL; /**< log callback context */

/**

 *  log callback

 */

static void (*m_callback_log)(void *, const size_t, const char *);

static int log_init_successful = 0; /**< log init gatekeeper */

/**

 * ---------------------------------------

 * Local functions

 * ---------------------------------------

 */

/**

 * =======================================

 * initialize and shutdown

 * =======================================

 */

int

log_init(int fd_log,

         void (*callback_log)(void *, const size_t, const char *),

         void *context_log,

         int verbosity)

{

        /**

         * Set log message verbosity

         */

        switch (verbosity) {

        case LOG_VER_SILENT:

                m_opt = LOG_OPT_SILENT;

                log_init_successful = 1;

                return LOG_RETVAL_OK;

        case LOG_VER_DEFAULT:

                m_opt = LOG_OPT_DEFAULT;

                break;

        case LOG_VER_VERBOSE:

                m_opt = LOG_OPT_VERBOSE;

                break;

        case LOG_VER_SUPER_VERBOSE:

                m_opt = LOG_OPT_SUPER_VERBOSE;

                break;

        default:

                m_opt = LOG_OPT_SUPER_VERBOSE;

                break;

        }

        if (fd_log < 0 && callback_log == NULL) {

                fprintf(stderr, "%s: no LOG destination selected\n", __func__);

                return LOG_RETVAL_ERROR;

        }

        m_fd = fd_log;

        m_callback_log = callback_log;

        m_context_log = context_log;

        log_init_successful = 1;

        return LOG_RETVAL_OK;

}

int

log_fini(void)

{

        if (m_opt == LOG_OPT_SILENT) {

                log_init_successful = 0;

                return LOG_RETVAL_OK;

        }

        m_opt = 0;

        m_fd = -1;

        m_callback_log = NULL;

        m_context_log = NULL;

        log_init_successful = 0;

        return LOG_RETVAL_OK;

}

void

log_printf(int type, const char *str, ...)

{

        va_list ap;

        char ap_buffer[AP_BUFFER_SIZE];

        int size;

        /* If log_init has not been successful then

         * log_printf should not work. */

        ASSERT(log_init_successful == 1);

        if (log_init_successful == 0)

                return;

        if (m_opt == LOG_OPT_SILENT)

                return;

        if ((m_opt & type) == 0)

                return;

        ASSERT(str != NULL);

        if (str == NULL)

                return;

        va_start(ap, str);

        ap_buffer[AP_BUFFER_SIZE - 1] = '\0';

        size = vsnprintf(ap_buffer, AP_BUFFER_SIZE - 1, str, ap);

        va_end(ap);

        ASSERT(size >= 0);

        if (size < 0)

                return;

        if (m_callback_log != NULL)

                m_callback_log(m_context_log, size, ap_buffer);

        if (m_fd >= 0) {

                if (write(m_fd, ap_buffer, size) < 0)

                        fprintf(stderr, "%s: printing to file failed\n",

                                __func__);

        }

}