iPXE
getopt.c
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1 /*
2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 #include <stdint.h>
27 #include <string.h>
28 #include <stdio.h>
29 #include <getopt.h>
30 
31 /** @file
32  *
33  * Parse command-line options
34  *
35  */
36 
37 /**
38  * Option argument
39  *
40  * This will point to the argument for the most recently returned
41  * option, if applicable.
42  */
43 char *optarg;
44 
45 /**
46  * Current option index
47  *
48  * This is an index into the argv[] array. When getopt() returns -1,
49  * @c optind is the index to the first element that is not an option.
50  */
51 int optind;
52 
53 /**
54  * Current option character index
55  *
56  * This is an index into the current element of argv[].
57  */
59 
60 /**
61  * Unrecognised option
62  *
63  * When an unrecognised option is encountered, the actual option
64  * character is stored in @c optopt.
65  */
66 int optopt;
67 
68 /**
69  * Get option argument from argv[] array
70  *
71  * @v argc Argument count
72  * @v argv Argument list
73  * @ret argument Option argument, or NULL
74  *
75  * Grab the next element of argv[], if it exists and is not an option.
76  */
77 static const char * get_argv_argument ( int argc, char * const argv[] ) {
78  char *arg;
79 
80  /* Don't overrun argv[] */
81  if ( optind >= argc )
82  return NULL;
83  arg = argv[optind];
84 
85  /* If next argv element is an option, then it's not usable as
86  * an argument.
87  */
88  if ( *arg == '-' )
89  return NULL;
90 
91  /** Consume this argv element, and return it */
92  optind++;
93  return arg;
94 }
95 
96 /**
97  * Match long option
98  *
99  * @v argc Argument count
100  * @v argv Argument list
101  * @v opttext Option text within current argv[] element
102  * @v longopt Long option specification
103  * @ret option Option to return from getopt()
104  * @ret matched Found a match for this long option
105  */
106 static int match_long_option ( int argc, char * const argv[],
107  const char *opttext,
108  const struct option *longopt, int *option ) {
109  size_t optlen;
110  const char *argument = NULL;
111 
112  /* Compare option name */
113  optlen = strlen ( longopt->name );
114  if ( strncmp ( opttext, longopt->name, optlen ) != 0 )
115  return 0;
116 
117  /* Check for inline argument */
118  if ( opttext[optlen] == '=' ) {
119  argument = &opttext[ optlen + 1 ];
120  } else if ( opttext[optlen] ) {
121  /* Long option with trailing garbage - no match */
122  return 0;
123  }
124 
125  /* Consume this argv element */
126  optind++;
127 
128  /* If we want an argument but don't have one yet, try to grab
129  * the next argv element
130  */
131  if ( ( longopt->has_arg != no_argument ) && ( ! argument ) )
132  argument = get_argv_argument ( argc, argv );
133 
134  /* If we need an argument but don't have one, sulk */
135  if ( ( longopt->has_arg == required_argument ) && ( ! argument ) ) {
136  printf ( "Option \"%s\" requires an argument\n",
137  longopt->name );
138  *option = ':';
139  return 1;
140  }
141 
142  /* If we have an argument where we shouldn't have one, sulk */
143  if ( ( longopt->has_arg == no_argument ) && argument ) {
144  printf ( "Option \"%s\" takes no argument\n", longopt->name );
145  *option = ':';
146  return 1;
147  }
148 
149  /* Store values and return success */
150  optarg = ( char * ) argument;
151  if ( longopt->flag ) {
152  *(longopt->flag) = longopt->val;
153  *option = 0;
154  } else {
155  *option = longopt->val;
156  }
157  return 1;
158 }
159 
160 /**
161  * Match short option
162  *
163  * @v argc Argument count
164  * @v argv Argument list
165  * @v opttext Option text within current argv[] element
166  * @v shortopt Option character from option specification
167  * @ret option Option to return from getopt()
168  * @ret matched Found a match for this short option
169  */
170 static int match_short_option ( int argc, char * const argv[],
171  const char *opttext, int shortopt,
172  enum getopt_argument_requirement has_arg,
173  int *option ) {
174  const char *argument = NULL;
175 
176  /* Compare option character */
177  if ( *opttext != shortopt )
178  return 0;
179 
180  /* Consume option character */
181  opttext++;
182  nextchar++;
183  if ( *opttext ) {
184  if ( has_arg != no_argument ) {
185  /* Consume remainder of element as inline argument */
186  argument = opttext;
187  optind++;
188  nextchar = 0;
189  }
190  } else {
191  /* Reached end of argv element */
192  optind++;
193  nextchar = 0;
194  }
195 
196  /* If we want an argument but don't have one yet, try to grab
197  * the next argv element
198  */
199  if ( ( has_arg != no_argument ) && ( ! argument ) )
200  argument = get_argv_argument ( argc, argv );
201 
202  /* If we need an argument but don't have one, sulk */
203  if ( ( has_arg == required_argument ) && ( ! argument ) ) {
204  printf ( "Option \"%c\" requires an argument\n", shortopt );
205  *option = ':';
206  return 1;
207  }
208 
209  /* Store values and return success */
210  optarg = ( char * ) argument;
211  *option = shortopt;
212  return 1;
213 }
214 
215 /**
216  * Parse command-line options
217  *
218  * @v argc Argument count
219  * @v argv Argument list
220  * @v optstring Option specification string
221  * @v longopts Long option specification table
222  * @ret longindex Index of long option (or NULL)
223  * @ret option Option found, or -1 for no more options
224  *
225  * Note that the caller must arrange for reset_getopt() to be called
226  * before each set of calls to getopt_long(). In Etherboot, this is
227  * done automatically by execv().
228  */
229 int getopt_long ( int argc, char * const argv[], const char *optstring,
230  const struct option *longopts, int *longindex ) {
231  const char *opttext = argv[optind];
232  const struct option *longopt;
233  int shortopt;
235  int option;
236 
237  /* Check for end of argv array */
238  if ( optind >= argc )
239  return -1;
240 
241  /* Check for end of options */
242  if ( *(opttext++) != '-' )
243  return -1;
244 
245  /* Check for long options */
246  if ( *(opttext++) == '-' ) {
247  /* "--" indicates end of options */
248  if ( *opttext == '\0' ) {
249  optind++;
250  return -1;
251  }
252  for ( longopt = longopts ; longopt->name ; longopt++ ) {
253  if ( ! match_long_option ( argc, argv, opttext,
254  longopt, &option ) )
255  continue;
256  if ( longindex )
257  *longindex = ( longopt - longopts );
258  return option;
259  }
260  optopt = '?';
261  printf ( "Unrecognised option \"--%s\"\n", opttext );
262  return '?';
263  }
264 
265  /* Check for short options */
266  if ( nextchar < 1 )
267  nextchar = 1;
268  opttext = ( argv[optind] + nextchar );
269  while ( ( shortopt = *(optstring++) ) ) {
271  while ( *optstring == ':' ) {
272  has_arg++;
273  optstring++;
274  }
275  if ( match_short_option ( argc, argv, opttext, shortopt,
276  has_arg, &option ) ) {
277  return option;
278  }
279  }
280  optopt = *opttext;
281  printf ( "Unrecognised option \"-%c\"\n", optopt );
282  return '?';
283 }
static const char * get_argv_argument(int argc, char *const argv[])
Get option argument from argv[] array.
Definition: getopt.c:77
int nextchar
Current option character index.
Definition: getopt.c:58
int printf(const char *fmt,...)
Write a formatted string to the console.
Definition: vsprintf.c:464
int optopt
Unrecognised option.
Definition: getopt.c:66
int optind
Current option index.
Definition: getopt.c:51
int val
Value to return.
Definition: getopt.h:49
int strncmp(const char *first, const char *second, size_t max)
Compare strings.
Definition: string.c:170
Parse command-line options.
A long option, as used for getopt_long()
Definition: getopt.h:24
static int match_short_option(int argc, char *const argv[], const char *opttext, int shortopt, enum getopt_argument_requirement has_arg, int *option)
Match short option.
Definition: getopt.c:170
getopt_argument_requirement
Definition: getopt.h:14
const char * name
Long name of this option.
Definition: getopt.h:26
size_t strlen(const char *src)
Get length of string.
Definition: string.c:213
Option does not take an argument.
Definition: getopt.h:16
int getopt_long(int argc, char *const argv[], const char *optstring, const struct option *longopts, int *longindex)
Parse command-line options.
Definition: getopt.c:229
int * flag
Location into which to store val, or NULL.
Definition: getopt.h:37
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
Option requires an argument.
Definition: getopt.h:18
char * optarg
Option argument.
Definition: getopt.c:43
int has_arg
Option takes an argument.
Definition: getopt.h:32
#define NULL
NULL pointer (VOID *)
Definition: Base.h:362
static int match_long_option(int argc, char *const argv[], const char *opttext, const struct option *longopt, int *option)
Match long option.
Definition: getopt.c:106
String functions.