looper/subprojects/mpg123/src/getlopt.h
2024-09-28 10:31:18 -07:00

83 lines
2.3 KiB
C

/*
getlopt: command line option/parameter parsing
copyright ?-2006 by the mpg123 project - free software under the terms of the LGPL 2.1
see COPYING and AUTHORS files in distribution or http://mpg123.org
initially written Oliver Fromme
old timestamp: Tue Apr 8 07:13:39 MET DST 1997
*/
#include <stdlib.h>
#include <string.h>
#ifndef _MPG123_GETLOPT_H_
#define _MPG123_GETLOPT_H_
extern int loptind; /* index in argv[] */
extern int loptchr; /* index in argv[loptind] */
extern char *loptarg; /* points to argument if present, else to option */
struct topt;
typedef struct topt topt;
struct topt {
char sname; /* short option name, can be 0 */
char *lname; /* long option name, can be 0 */
int flags; /* see below */
void (*func)(char *, topt *); /* called if != 0 (after setting of var) */
void *var; /* type is *long, *char or **char, see below */
long value;
};
/* ThOr: make this clear; distict long from int (since this is != on my Alpha) and really use a flag for every case (spare the 0 case
for .... no flag) */
#define GLO_ARG 1
#define GLO_CHAR 2
#define GLO_INT 4
#define GLO_LONG 8
#define GLO_DOUBLE 16
/* This is set if getlopt allocates memory for var. */
#define GLO_VAR_MEM 32
/* flags:
* bit 0 = 0 - no argument
* if var != NULL
* *var := value or (char)value [see bit 1]
* else
* loptarg = &option
* return ((value != 0) ? value : sname)
* bit 0 = 1 - argument required
* if var != NULL
* *var := atoi(arg) or strdup(arg) [see bit 1]
* else
* loptarg = &arg
* return ((value != 0) ? value : sname)
*
* bit 1 = 1 - var is a pointer to a char (or string),
* and value is interpreted as char
* bit 2 = 1 - var is a pointer to int
* bit 3 = 1 - var is a pointer to long
*
* Note: The options definition is terminated by a topt
* containing only zeroes.
*/
#define GLO_END 0
#define GLO_UNKNOWN -1
#define GLO_NOARG -2
#define GLO_CONTINUE -3
#define GLO_BADARG -4
int getlopt (int argc, char *argv[], topt *opts);
// Helper to set a char parameter, avoiding memory leaks.
void getlopt_set_char(topt *opts, char *name, char *value);
/* return values:
* GLO_END (0) end of options
* GLO_UNKNOWN (-1) unknown option *loptarg
* GLO_NOARG (-2) missing argument
* GLO_CONTINUE (-3) (reserved for internal use)
* else - return value according to flags (see above)
*/
#endif