text: /*
   * Copyright (c) 2020 rxi
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to
   * deal in the Software without restriction, including without limitation the
   * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   * sell copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
   * IN THE SOFTWARE.
   */
  
  #include "log.h"
  
  log_Logger L;
  
  const char *level_strings[] = {
    "TRACE", "DEBUG", "INFO", "WARN", "ERROR", "FATAL"
  };
  const char *level_colors[] = {
    "\x1b[94m", "\x1b[36m", "\x1b[32m", "\x1b[33m", "\x1b[31m", "\x1b[35m"
  };
  
  
  static void stdout_callback(log_Event *ev) {
    char buf[16];
    buf[strftime(buf, sizeof(buf), "%H:%M:%S", ev->time)] = '\0';
  #ifdef LOG_USE_COLOR
    fprintf(
      ev->udata, "%s|\x1b[90m%010u\x1b[0m %s%-5s\x1b[0m \x1b[90m%s:%d:\x1b[0m ",
      buf, (unsigned)pthread_self(), level_colors[ev->level], level_strings[ev->level],
      ev->file, ev->line);
  #else
    fprintf(
      ev->udata, "%s|%010u %-5s %s:%d: ",
      buf, (unsigned)pthread_self(), level_strings[ev->level], ev->file, ev->line);
  #endif
    vfprintf(ev->udata, ev->fmt, ev->ap);
    fprintf(ev->udata, "\n");
    fflush(ev->udata);
  }
  
  
  static void file_callback(log_Event *ev) {
    char buf[64];
    buf[strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S", ev->time)] = '\0';
    fprintf(
      ev->udata, "%s|%010u %-5s %s:%d: ",
      buf, (unsigned)pthread_self(), level_strings[ev->level], ev->file, ev->line);
    vfprintf(ev->udata, ev->fmt, ev->ap);
    fprintf(ev->udata, "\n");
    fflush(ev->udata);
  }
  
  
  static void lock(void)   {
    if (L.lock) { L.lock(true, L.udata); }
  }
  
  
  static void unlock(void) {
    if (L.lock) { L.lock(false, L.udata); }
  }
  
  
  const char* log_level_string(int level) {
    return level_strings[level];
  }
  
  
  void _log_set_lock(log_Logger *L, log_LockFn fn, void *udata) {
    L->lock = fn;
    L->udata = udata;
  }
  
  
  void _log_set_level(log_Logger *L, int level) {
    L->level = level;
  }
  
  
  void _log_set_quiet(log_Logger *L, bool enable) {
    L->quiet = enable;
  }
  
  
  int _log_add_callback(log_Logger *L, log_LogFn fn, void *udata, int level) {
    int i;
  
    for (i = 0; i < LOG_MAX_CALLBACKS; i++) {
      if (!L->callbacks[i].fn) {
        L->callbacks[i] = (log_Callback) { fn, udata, level };
        return 0;
      }
    }
    return -1;
  }
  
  
  int _log_add_fp(log_Logger *L, FILE *fp, int level) {
    return _log_add_callback(L, file_callback, fp, level);
  }
  
  
  static void init_event(log_Event *ev, void *udata) {
    if (!ev->time) {
      time_t t = time(NULL);
      ev->time = localtime(&t);
    }
    ev->udata = udata;
  }
  
  
  void _log_log(log_Logger *L, int level, const char *file, int line, const char *fmt, ...) {
    int i;
    log_Event ev = {
      .fmt   = fmt,
      .file  = file,
      .line  = line,
      .level = level,
    };
  
    lock();
  
    if (!L->quiet && level >= L->level) {
      init_event(&ev, stderr);
      va_start(ev.ap, fmt);
      stdout_callback(&ev);
      va_end(ev.ap);
    }
  
    for (i = 0; i < LOG_MAX_CALLBACKS && L->callbacks[i].fn; i++) {
      log_Callback *cb = &L->callbacks[i];
      if (level >= cb->level) {
        init_event(&ev, cb->udata);
        va_start(ev.ap, fmt);
        cb->fn(&ev);
        va_end(ev.ap);
      }
    }
  
    unlock();
  }
  