1 /** 2 * \file 3 * \brief getopt 4 */ 5 /* 6 * (c) 2008-2009 Adam Lackorzynski <adam@os.inf.tu-dresden.de>, 7 * Alexander Warg <warg@os.inf.tu-dresden.de> 8 * economic rights: Technische Universität Dresden (Germany) 9 * This file is part of TUD:OS and distributed under the terms of the 10 * GNU Lesser General Public License 2.1. 11 * Please see the COPYING-LGPL-2.1 file for details. 12 */ 13 #ifndef _GETOPT_H 14 #define _GETOPT_H 15 16 #ifndef NULL 17 #define NULL 0 18 #endif 19 20 #include <l4/sys/compiler.h> 21 22 EXTERN_C_BEGIN 23 24 /* For communication from `getopt' to the caller. 25 When `getopt' finds an option that takes an argument, 26 the argument value is returned here. 27 Also, when `ordering' is RETURN_IN_ORDER, 28 each non-option ARGV-element is returned here. */ 29 30 extern char *optarg; 31 32 /* Index in ARGV of the next element to be scanned. 33 This is used for communication to and from the caller 34 and for communication between successive calls to `getopt'. 35 36 On entry to `getopt', zero means this is the first call; initialize. 37 38 When `getopt' returns -1, this is the index of the first of the 39 non-option elements that the caller should itself scan. 40 41 Otherwise, `optind' communicates from one call to the next 42 how much of ARGV has been scanned so far. */ 43 44 extern int optind; 45 46 /* Callers store zero here to inhibit the error message `getopt' prints 47 for unrecognized options. */ 48 49 extern int opterr; 50 51 /* Set to an option character which was unrecognized. */ 52 53 extern int optopt; 54 55 /* Describe the long-named options requested by the application. 56 The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector 57 of `struct option' terminated by an element containing a name which is 58 zero. 59 60 The field `has_arg' is: 61 no_argument (or 0) if the option does not take an argument, 62 required_argument (or 1) if the option requires an argument, 63 optional_argument (or 2) if the option takes an optional argument. 64 65 If the field `flag' is not NULL, it points to a variable that is set 66 to the value given in the field `val' when the option is found, but 67 left unchanged if the option is not found. 68 69 To have a long-named option do something other than set an `int' to 70 a compiled-in constant, such as set a value from `optarg', set the 71 option's `flag' field to zero and its `val' field to a nonzero 72 value (the equivalent single-letter option character, if there is 73 one). For long options that have a zero `flag' field, `getopt' 74 returns the contents of the `val' field. */ 75 76 struct option 77 { 78 const char *name; 79 /* has_arg can't be an enum because some compilers complain about 80 type mismatches in all the code that assumes it is an int. */ 81 int has_arg; 82 int *flag; 83 int val; 84 }; 85 86 /* Names for the values of the `has_arg' field of `struct option'. */ 87 88 #define no_argument 0 89 #define required_argument 1 90 #define optional_argument 2 91 92 L4_CV int getopt (int argc, char *const *argv, const char *shortopts); 93 94 L4_CV int getopt_long (int argc, char *const *argv, const char *shortopts, 95 const struct option *longopts, int *longind); 96 L4_CV int getopt_long_only (int argc, char *const *argv, 97 const char *shortopts, 98 const struct option *longopts, int *longind); 99 100 L4_CV int _getopt_internal (int argc, char *const *argv, 101 const char *shortopts, 102 const struct option *longopts, int *longind, 103 int long_only); 104 105 EXTERN_C_END 106 107 #endif /* _GETOPT_H */ 108