lv_log.c

/* Libvisual - The audio visualisation framework.
 *
 * Copyright (C) 2012      Libvisual team
 *               2004-2006 Dennis Smit
 *
 * Authors: Chong Kai Xiong <kaixiong@codeleft.sg>
 *          Dennis Smit <ds@nerds-incorporated.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1
 * 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser 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 <config.h>
#include "lv_log.h"
#include "lv_common.h"
#include "lv_util.h"
#include <stdio.h>
#include <stdarg.h>
#include <string.h>

#define LV_LOG_MAX_MESSAGE_SIZE 1024

typedef struct {
    VisLogHandlerFunc  func;
    void              *priv;
} LogHandler;

static VisLogSeverity verbosity = VISUAL_LOG_WARNING;

static const char *log_prefixes[VISUAL_LOG_NUM_LEVELS] = {
    "DEBUG    ",
    "INFO     ",
    "WARNING  ",
    "ERROR    ",
    "CRITICAL "
};

static LogHandler log_handlers[VISUAL_LOG_NUM_LEVELS];

static void output_to_stderr (VisLogSeverity severity, const char *msg,
    VisLogSource const *source);

static int is_valid_severity (VisLogSeverity severity)
{
    return (severity >= VISUAL_LOG_DEBUG && severity < VISUAL_LOG_NUM_LEVELS);
}

void visual_log_set_verbosity (VisLogSeverity level)
{
    verbosity = level;
}

VisLogSeverity visual_log_get_verbosity ()
{
    return verbosity;
}

void visual_log_set_handler (VisLogSeverity severity, VisLogHandlerFunc func, void *priv)
{
    LogHandler *handler;

    visual_return_if_fail (is_valid_severity (severity));

    handler = &log_handlers[severity];
    handler->func = func;
    handler->priv = priv;
}

void _lv_log (VisLogSeverity severity,
    const char *file, int line, const char *funcname,
    const char *fmt, ...)
{
    VisLogSource source;

    LogHandler *handler;
    char message[LV_LOG_MAX_MESSAGE_SIZE];
    va_list va;

    if (!is_valid_severity (severity) || fmt == NULL) {
        visual_log (VISUAL_LOG_ERROR, "(malformed message)");
        return;
    }

    if (verbosity > severity) {
         return;
    }

    va_start (va, fmt);
    vsnprintf (message, LV_LOG_MAX_MESSAGE_SIZE-1, fmt, va);
    va_end (va);

    source.file = visual_truncate_path (file, 3);
    source.func = funcname;
    source.line = line;

    handler = &log_handlers[severity];

    if (handler->func != NULL) {
        handler->func (severity, message, &source, handler->priv);
    } else {
        output_to_stderr (severity, message, &source);
    }
}

static void output_to_stderr (VisLogSeverity severity, const char *msg,
    VisLogSource const *source)
{
    fprintf (stderr, "%s %s:%d:%s: %s\n", log_prefixes[severity],
         source->file, source->line, source->func, msg);
    fflush (stderr);
}