common.h

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/* common.h - Common functions
 
   Copyright (C) 1993 Werner Almesberger <werner.almesberger@lrc.di.epfl.ch>
   Copyright (C) 2008-2014 Daniel Baumann <mail@daniel-baumann.ch>
 
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 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 General Public License for more details.
 
   You should have received a copy of the GNU General Public License
   along with this program. If not, see <http://www.gnu.org/licenses/>.
 
   The complete text of the GNU General Public License
   can be found in /usr/share/common-licenses/GPL-3 file.
*/
 
#ifndef _COMMON_H
#define _COMMON_H
 
#include <sys/types.h>
 
#include <limits.h>
#include <stdint.h>
 
#ifndef OFF_MAX
    #define OFF_MAX (off_t)((1ULL << (sizeof(off_t) * CHAR_BIT - 1)) - 1)
#endif
 
extern int interactive;
extern int write_immed;
extern int atari_format;    /* Use Atari variation of MS-DOS FS format */
 
/* program_name used for printing messages; no name will be printed when it is
 * left as NULL */
extern const char *program_name;
 
void die(const char *msg, ...)
    __attribute((noreturn, format(printf, 1, 2)));
 
/* Displays a prinf-style message and terminates the program. */
 
void pdie(const char *msg, ...)
    __attribute((noreturn, format(printf, 1, 2)));
 
/* Like die, but appends an error message according to the state of errno. */
 
void *alloc(int size);
 
/* mallocs SIZE bytes and returns a pointer to the data. Terminates the program
   if malloc fails. */
 
void *qalloc(void **root, int size);
 
/* Like alloc, but registers the data area in a list described by ROOT. */
 
void qfree(void **root);
 
/* Deallocates all qalloc'ed data areas described by ROOT. */
 
int min(int a, int b);
 
/* Returns the smaller integer value of a and b. */
 
int xasprintf(char **strp, const char *fmt, ...)
    __attribute((format(printf, 2, 3)));
 
/* Runs asprintf() and terminates the program if it fails. */
 
int get_choice(int noninteractive_result, const char *noninteractive_msg,
           int choices, ...);
 
/*
 * Display a numbered list of choices and accept user input to select one. If
 * interactive is false, it will instead print noninteractive_msg and return
 * noninteractive_result. The number of options must be given in choices and
 * must be more than one and less then ten.
 *
 * The variable arguments are choices times <int val, const char *desc>, where
 * val is the value that is returned when the user selects this option and desc
 * is the string describing this option.
 */
 
char *get_line(const char *prompt, char *dest, size_t length);
 
/*
 * Display prompt and read a line, placing it in dest with at most length-1
 * characters plus a null byte. This behaves like printing a prompt and fgets()
 * afterwards with the addition of temporarily enabling canonical input mode
 * with echo if needed.
 */
 
void check_atari(void);
 
/*
 * ++roman: On m68k Linux, check if this is an Atari; if yes, turn on Atari
 * variant of MS-DOS filesystem by default.
 */
 
uint32_t generate_volume_id(void);
 
/*
 * Generate a 32 bit volume ID
 */
 
int validate_volume_label(char *doslabel);
 
/*
 * Validate volume label
 */
 
#endif