/* vi: set tabstop=4 shiftwidth=4: */

/*
 * $Id: error.c,v 1.2 1996/12/28 22:11:08 schweikh Exp $
 */

/*@ignore@ */
#ifndef _POSIX_SOURCE
#define _POSIX_SOURCE 1
#endif
/*@end@ */

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "shutup.h"
#include "error.h"

/*@-ptrarith@ */
/*@-redecl@ */

/*
 * progname is a short string prepended to error messages.
 */

 /*@i1@ */ static char *progname = "(program name not assigned)";

void
err_ret (const char *,...)
 /* @globals progname@ */ ;

     void err_sys (const char *,...)
 /* @globals progname@ */ ;

     void err_dump (const char *,...)
 /* @globals progname@ */ ;

     void err_msg (const char *,...)
 /* @globals progname@ */ ;

     void err_quit (const char *,...)
 /* @globals progname@ */ ;

     void err_progname (void)
 /* @globals progname,stderr,fileSystem@ */
 /* @modifies *stderr,fileSystem@ */ ;

     char *
       program_name (void)
 /* @globals progname@ */ ;

     static void err_doit (int, const char *, va_list ap)
 /* @globals progname,stderr,fileSystem,errno@ */
 /* @modifies *stderr,fileSystem,ap,errno@ */ ;

     void set_progname (char *, char *)
 /* @globals progname,internalState@ */
 /* @modifies progname,internalState@ */ ;

     void cfprintf (FILE * fp, const char *,...)
 /* @globals progname@ */
 /* @modifies *fp@ */ ;

     char *
       program_name (void)
{
  return progname;
}

/*
 * Checked fprintf: do fprintf and exit if it failed
 * (probably due to an I/O or "no space on device" error).
 */
void
cfprintf (FILE * fp, const char *fmt,...)
{
  va_list ap;

  va_start (ap, fmt);
  if (vfprintf (fp, fmt, ap) < 0)
    {
      err_sys ("fprintf failed for format `%s'", fmt);
    }
  va_end (ap);
}

/*
 * Print the program name and nothig else on stderr.
 */

void
err_progname (void)
{
  Fprintf (stderr, "%s", progname);
  Fflush (stderr);
}

void
set_progname (char *argv0, char *def)
{
  if (argv0 == NULL || argv0[0] == '\0')
    {
      progname = def;
    }
  else
    {
      char *p = strrchr (argv0, '/');

      if (p == NULL)
        {
          progname = argv0;
        }
      else
        {
          progname = p + 1;     /* skip '/' */
        }
    }
}

/*
 * Nonfatal error related to a system call. Print a message and return.
 */

void
err_ret (const char *fmt,...)
{
  va_list ap;
  va_start (ap, fmt);
  err_doit (1, fmt, ap);
  va_end (ap);
}

/*
 * Fatal error related to a system call. Print a message and exit().
 */

void
err_sys (const char *fmt,...)
{
  va_list ap;
  va_start (ap, fmt);
  err_doit (1, fmt, ap);
  va_end (ap);
  exit (EXIT_FAILURE);
}

/*
 * Fatal error related to a system call. Print a message and dump core.
 */

void
err_dump (const char *fmt,...)
{
  va_list ap;
  va_start (ap, fmt);
  err_doit (1, fmt, ap);
  va_end (ap);
  abort ();
  /* @NOTREACHED@ */
  exit (EXIT_FAILURE);          /* should never get here */
}

/*
 * Nonfatal error unrelated to a system call. Print a message and return.
 */

void
err_msg (const char *fmt,...)
{
  va_list ap;
  va_start (ap, fmt);
  err_doit (0, fmt, ap);
  va_end (ap);
}

/*
 * Fatal error unrelated to a system call. Print a message and exit().
 */

void
err_quit (const char *fmt,...)
{
  va_list ap;
  va_start (ap, fmt);
  err_doit (0, fmt, ap);
  va_end (ap);
  exit (EXIT_FAILURE);
}

static void
err_doit (int errnoflag, const char *fmt, va_list ap)
{
  int errno_save = errno;

  Fflush (stdout);
  Fprintf (stderr, "%s: ", progname);
  Vfprintf (stderr, fmt, ap);
  if (errnoflag != 0)
    {
      Fputc (':', stderr);
      Fputc (' ', stderr);
      errno = errno_save;
      perror (NULL);
    }
  else
    {
      Fputc ('\n', stderr);
    }
  Fflush (NULL);
}