spew.c

/* 
 shm-arena    shared memory arena
 Copyright (C) 2006-2008 Lance Arsenault (LGPL v3)


    This file is part of shm-arena.

    shm-arena 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 3 of the
    License, or (at your option) any later version.

    shm-arena 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, see
    <http://www.gnu.org/licenses/>.
*/

#include "config.h"

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <errno.h>
#include <limits.h>
#include <pthread.h>

#include "spew.h"


#ifdef TTY_COLOR

/* see the colors by running in a bash shell
 * on a interactive terminal:

i=30; \
while [ "$i" -lt "48" ] ; \
do \
 echo -e " \033[0${i}mCOLOR \\\033[0${i}m\033[000m"; \
 i=$(($i + 1)); \
done

*/

# define WARN_COLOR  "\033[031m"
# define INFO_COLOR  "\033[032m"
# define DEBUG_COLOR "\033[036m"
# define END_COLOR   "\033[000m"

DLL_LOCAL
const char *_shm_tty_color[4] =
  { END_COLOR, WARN_COLOR, INFO_COLOR, DEBUG_COLOR };

DLL_LOCAL
int _shm_with_tty_color = 1;

#endif /* #ifdef TTY_COLOR */




#define DEFAULT_SPEW_FILE    (stdout)

static FILE *spew_file = NULL;
static int spew_level = DEFAULT_SPEW_LEVEL;

DLL_LOCAL
const char *_shm_spew_levels[] =
{
  "", "WARN", "INFO", "DEBUG"
};

DLL_LOCAL
void _shm_spew_init(void)
{
  if(spew_file) return;

  {
    char *env;

    /*****************************************************************
        set       SPEW LEVEL
    *****************************************************************/
    
    env = getenv("SHM_SPEW");
    
    
    if(env) /* The user overrides the default compiled in spew level. */
      {
    long val;
    int errno_save;
    
    /* try a number value for env */
    errno_save = errno;
    errno = 0;
    val = strtol(env, (char **) NULL, 10);
    if(errno || val == 0) val = LONG_MIN;
    errno = errno_save;
    /* Tried to think of all cases that a user might guess to use
     * while working as documented. */
    if(!strncasecmp("WARN", env, 1) ||
       !strncasecmp("NOTICE", env, 4) ||
       !strncasecmp("ON", env, 2) ||
       !strncasecmp("YES", env, 1) ||
       (val != LONG_MIN && val == 1))
      spew_level = _WARN;
    else if(!strncasecmp("DEBUG", env, 1) ||
        (val != LONG_MIN && val >= 3))
      spew_level = _DEBUG;
    else if(!strncasecmp("OFF", env, 2) ||
        !strncasecmp("NONE", env, 1) ||
        !strncasecmp("SILENT", env, 1) ||
        !strcmp("0", env) ||
        (val != LONG_MIN && val <= 0))
      spew_level = _SILENT;
    else /* INFO is the default if env is set at all */
      spew_level = _INFO;
      }

    /*****************************************************************
         set       SPEW FILE
    *****************************************************************/
    spew_file = DEFAULT_SPEW_FILE;
    env = getenv("SHM_SPEW_FILE");
    if(env) /* The user overrides the default spew file. */
      {
    /* Tried to think of all cases that a user might guess to use
     * while working as documented. */
    if(!strcasecmp("STDOUT", env) ||
       !strcmp("1", env))
      spew_file = stdout;
    else if(!strcasecmp("STDERR", env) ||
        !strcmp("2", env))
      spew_file = stderr;
    else
      spew_file = fopen(env, "a");
    
    if(!spew_file)
      spew_file = DEFAULT_SPEW_FILE;
      }

    /*****************************************************************
        set       TTY_COLOR
    *****************************************************************/
    
#ifdef TTY_COLOR

    env = getenv("SHM_TTY_COLOR");
    if(!env)
      env = getenv("SHM_COLOR");
    
    if(env) /* The user overrides the default compiled in. */
      {
    /* Tried to think of all cases that a user might guess to use
     * while working as documented. */
    if(!strncasecmp("OFF", env, 2) ||
       !strcmp("0", env) ||
       !strncasecmp("NO", env, 1) ||
       (!strncasecmp("AUTO", env, 1) && !isatty(fileno(spew_file))))
      /* turn off the color escape strings */
      _shm_with_tty_color = 0;
    /* else  It's already on. */
      }
    else if(!isatty(fileno(spew_file)))
      /* turn off the color escape strings */
      _shm_with_tty_color = 0;
    

#endif /* #ifdef TTY_COLOR */


    SPEW(_DEBUG, "SHM_SPEW level is set to DEBUG");
  }
}


DLL_LOCAL
void _shm_spew(int level, const char *fmt, ...)
{
  if(spew_level >= level)
    {
      va_list ap;
      va_start(ap, fmt);
      vfprintf(spew_file, fmt, ap);
      va_end(ap);
    }
}