/* Error handler for noninteractive utilities
 * Copyright (C) 1990,91,92,93,94,95,96,97,98 Free Software Foundation, Inc.
 * 
 * This file is part of the GNU C Library.  Its master source is NOT part of
 * the C library, however.  The master source lives in /gd/gnu/lib.
 * 
 * The GNU C Library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 * 
 * The GNU C Library 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
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with the GNU C Library; see the file COPYING.LIB.  If not,
 * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.  */

/* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */

#include "config.h"
#include <stdio.h>

#if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
# if __STDC__
#  include <stdarg.h>
#  define VA_START(args, lastarg) va_start(args, lastarg)
# else
#  include <varargs.h>
#  define VA_START(args, lastarg) va_start(args)
# endif
#else
# define va_alist a1, a2, a3, a4, a5, a6, a7, a8
# define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
#endif

#if STDC_HEADERS || _LIBC
# include <stdlib.h>
# include <string.h>
#else
void exit();
#endif

#include "error.h"

#ifndef _
# define _(String) String
#endif

/* If NULL, error will flush stdout, then print on stderr the program
 * name, a colon and a space.  Otherwise, error will call this
 * function without parameters instead.  */
void (*error_print_progname) (
#if __STDC__ - 0
				 void
#endif
    );

/* This variable is incremented each time `error' is called.  */
unsigned int error_message_count;

#ifdef _LIBC
/* In the GNU C library, there is a predefined variable for this.  */

# define program_name program_invocation_name
# include <errno.h>

/* In GNU libc we want do not want to use the common name `error' directly.
 * Instead make it a weak alias.  */
# define error __error
# define error_at_line __error_at_line

#else /* not _LIBC */

/* The calling program should define program_name and set it to the
 * name of the executing program.  */
extern char *program_name;

# ifdef HAVE_STRERROR_R
#  define __strerror_r strerror_r
# else
#  if HAVE_STRERROR
#   ifndef strerror		/* On some systems, strerror is a macro */
char *strerror();
#   endif
#  else
static char *private_strerror(errnum)
     int errnum;
{
extern char *sys_errlist[];
extern int sys_nerr;

    if (errnum > 0 && errnum <= sys_nerr)
	return _(sys_errlist[errnum]);
    return _("Unknown system error");
}

#   define strerror private_strerror
#  endif /* HAVE_STRERROR */
# endif	/* HAVE_STRERROR_R */
#endif /* not _LIBC */

/* Print the program name and error message MESSAGE, which is a printf-style
 * format string with optional args.
 * If ERRNUM is nonzero, print its corresponding system error message.
 * Exit with status STATUS if it is nonzero.  */
/* VARARGS */

void
#if defined VA_START && __STDC__
error(int status, int errnum, const char *message, ...)
#else
error(status, errnum, message, va_alist)
     int status;
     int errnum;
     char *message;
     va_dcl
#endif
{
#ifdef VA_START
va_list args;
#endif

    if (error_print_progname)
	(*error_print_progname) ();
    else {
	fflush(stdout);
	fprintf(stderr, "%s: ", program_name);
    }

#ifdef VA_START
    VA_START(args, message);
# if HAVE_VPRINTF || _LIBC
    vfprintf(stderr, message, args);
# else
    _doprnt(message, args, stderr);
# endif
    va_end(args);
#else
    fprintf(stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
#endif

    ++error_message_count;
    if (errnum) {
#if defined HAVE_STRERROR_R || defined _LIBC
char errbuf[1024];
	/* Don't use __strerror_r's return value because on some systems
	 * (at least DEC UNIX 4.0[A-D]) strerror_r returns `int'.  */
	__strerror_r(errnum, errbuf, sizeof errbuf);
	fprintf(stderr, ": %s", errbuf);
#else
	fprintf(stderr, ": %s", strerror(errnum));
#endif
    }
    putc('\n', stderr);
    fflush(stderr);
    if (status)
	exit(status);
}

/* Sometimes we want to have at most one error per line.  This
 * variable controls whether this mode is selected or not.  */
int error_one_per_line;

void
#if defined VA_START && __STDC__
error_at_line(int status, int errnum, const char *file_name,
	      unsigned int line_number, const char *message, ...)
#else
error_at_line(status, errnum, file_name, line_number, message, va_alist)
     int status;
     int errnum;
     const char *file_name;
     unsigned int line_number;
     char *message;
     va_dcl
#endif
{
#ifdef VA_START
va_list args;
#endif

    if (error_one_per_line) {
static const char *old_file_name;
static unsigned int old_line_number;

	if (old_line_number == line_number &&
	    (file_name == old_file_name || !strcmp(old_file_name, file_name)))
	    /* Simply return and print nothing.  */
	    return;

	old_file_name = file_name;
	old_line_number = line_number;
    }

    if (error_print_progname)
	(*error_print_progname) ();
    else {
	fflush(stdout);
	fprintf(stderr, "%s:", program_name);
    }

    if (file_name != NULL)
	fprintf(stderr, "%s:%d: ", file_name, line_number);

#ifdef VA_START
    VA_START(args, message);
# if HAVE_VPRINTF || _LIBC
    vfprintf(stderr, message, args);
# else
    _doprnt(message, args, stderr);
# endif
    va_end(args);
#else
    fprintf(stderr, message, a1, a2, a3, a4, a5, a6, a7, a8);
#endif

    ++error_message_count;
    if (errnum) {
#if defined HAVE_STRERROR_R || defined _LIBC
char errbuf[1024];
	fprintf(stderr, ": %s", __strerror_r(errnum, errbuf, sizeof errbuf));
#else
	fprintf(stderr, ": %s", strerror(errnum));
#endif
    }
    putc('\n', stderr);
    fflush(stderr);
    if (status)
	exit(status);
}

#ifdef _LIBC
/* Make the weak alias.  */
# undef error
# undef error_at_line
weak_alias(__error, error)
    weak_alias(__error_at_line, error_at_line)
#endif