1 /* argmatch.c -- find a match for a string in an array 2 3 Copyright (C) 1990, 1998-1999, 2001-2007, 2009-2012 Free Software 4 Foundation, Inc. 5 6 This program is free software: you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 3 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 18 19 /* Written by David MacKenzie <djm (at) ai.mit.edu> 20 Modified by Akim Demaille <demaille (at) inf.enst.fr> */ 21 22 #include <config.h> 23 24 /* Specification. */ 25 #include "argmatch.h" 26 27 #include <stdbool.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 32 #include "gettext.h" 33 #define _(msgid) gettext (msgid) 34 35 #include "error.h" 36 #include "quotearg.h" 37 #include "quote.h" 38 39 #if USE_UNLOCKED_IO 40 # include "unlocked-io.h" 41 #endif 42 43 /* When reporting an invalid argument, show nonprinting characters 44 by using the quoting style ARGMATCH_QUOTING_STYLE. Do not use 45 literal_quoting_style. */ 46 #ifndef ARGMATCH_QUOTING_STYLE 47 # define ARGMATCH_QUOTING_STYLE locale_quoting_style 48 #endif 49 50 /* Non failing version of argmatch call this function after failing. */ 51 #ifndef ARGMATCH_DIE 52 # include "exitfail.h" 53 # define ARGMATCH_DIE exit (exit_failure) 54 #endif 55 56 #ifdef ARGMATCH_DIE_DECL 57 ARGMATCH_DIE_DECL; 58 #endif 59 60 static void 61 __argmatch_die (void) 62 { 63 ARGMATCH_DIE; 64 } 65 66 /* Used by XARGMATCH and XARGCASEMATCH. See description in argmatch.h. 67 Default to __argmatch_die, but allow caller to change this at run-time. */ 68 argmatch_exit_fn argmatch_die = __argmatch_die; 69 70 71 /* If ARG is an unambiguous match for an element of the 73 NULL-terminated array ARGLIST, return the index in ARGLIST 74 of the matched element, else -1 if it does not match any element 75 or -2 if it is ambiguous (is a prefix of more than one element). 76 77 If VALLIST is none null, use it to resolve ambiguities limited to 78 synonyms, i.e., for 79 "yes", "yop" -> 0 80 "no", "nope" -> 1 81 "y" is a valid argument, for 0, and "n" for 1. */ 82 83 ptrdiff_t 84 argmatch (const char *arg, const char *const *arglist, 85 const char *vallist, size_t valsize) 86 { 87 size_t i; /* Temporary index in ARGLIST. */ 88 size_t arglen; /* Length of ARG. */ 89 ptrdiff_t matchind = -1; /* Index of first nonexact match. */ 90 bool ambiguous = false; /* If true, multiple nonexact match(es). */ 91 92 arglen = strlen (arg); 93 94 /* Test all elements for either exact match or abbreviated matches. */ 95 for (i = 0; arglist[i]; i++) 96 { 97 if (!strncmp (arglist[i], arg, arglen)) 98 { 99 if (strlen (arglist[i]) == arglen) 100 /* Exact match found. */ 101 return i; 102 else if (matchind == -1) 103 /* First nonexact match found. */ 104 matchind = i; 105 else 106 { 107 /* Second nonexact match found. */ 108 if (vallist == NULL 109 || memcmp (vallist + valsize * matchind, 110 vallist + valsize * i, valsize)) 111 { 112 /* There is a real ambiguity, or we could not 113 disambiguate. */ 114 ambiguous = true; 115 } 116 } 117 } 118 } 119 if (ambiguous) 120 return -2; 121 else 122 return matchind; 123 } 124 125 /* Error reporting for argmatch. 126 CONTEXT is a description of the type of entity that was being matched. 127 VALUE is the invalid value that was given. 128 PROBLEM is the return value from argmatch. */ 129 130 void 131 argmatch_invalid (const char *context, const char *value, ptrdiff_t problem) 132 { 133 char const *format = (problem == -1 134 ? _("invalid argument %s for %s") 135 : _("ambiguous argument %s for %s")); 136 137 error (0, 0, format, quotearg_n_style (0, ARGMATCH_QUOTING_STYLE, value), 138 quote_n (1, context)); 139 } 140 141 /* List the valid arguments for argmatch. 142 ARGLIST is the same as in argmatch. 143 VALLIST is a pointer to an array of values. 144 VALSIZE is the size of the elements of VALLIST */ 145 void 146 argmatch_valid (const char *const *arglist, 147 const char *vallist, size_t valsize) 148 { 149 size_t i; 150 const char *last_val = NULL; 151 152 /* We try to put synonyms on the same line. The assumption is that 153 synonyms follow each other */ 154 fputs (_("Valid arguments are:"), stderr); 155 for (i = 0; arglist[i]; i++) 156 if ((i == 0) 157 || memcmp (last_val, vallist + valsize * i, valsize)) 158 { 159 fprintf (stderr, "\n - %s", quote (arglist[i])); 160 last_val = vallist + valsize * i; 161 } 162 else 163 { 164 fprintf (stderr, ", %s", quote (arglist[i])); 165 } 166 putc ('\n', stderr); 167 } 168 169 /* Never failing versions of the previous functions. 170 171 CONTEXT is the context for which argmatch is called (e.g., 172 "--version-control", or "$VERSION_CONTROL" etc.). Upon failure, 173 calls the (supposed never to return) function EXIT_FN. */ 174 175 ptrdiff_t 176 __xargmatch_internal (const char *context, 177 const char *arg, const char *const *arglist, 178 const char *vallist, size_t valsize, 179 argmatch_exit_fn exit_fn) 180 { 181 ptrdiff_t res = argmatch (arg, arglist, vallist, valsize); 182 if (res >= 0) 183 /* Success. */ 184 return res; 185 186 /* We failed. Explain why. */ 187 argmatch_invalid (context, arg, res); 188 argmatch_valid (arglist, vallist, valsize); 189 (*exit_fn) (); 190 191 return -1; /* To please the compilers. */ 192 } 193 194 /* Look for VALUE in VALLIST, an array of objects of size VALSIZE and 195 return the first corresponding argument in ARGLIST */ 196 const char * 197 argmatch_to_argument (const char *value, 198 const char *const *arglist, 199 const char *vallist, size_t valsize) 200 { 201 size_t i; 202 203 for (i = 0; arglist[i]; i++) 204 if (!memcmp (value, vallist + valsize * i, valsize)) 205 return arglist[i]; 206 return NULL; 207 } 208 209 #ifdef TEST 210 /* 211 * Based on "getversion.c" by David MacKenzie <djm (at) gnu.ai.mit.edu> 212 */ 213 char *program_name; 214 215 /* When to make backup files. */ 216 enum backup_type 217 { 218 /* Never make backups. */ 219 no_backups, 220 221 /* Make simple backups of every file. */ 222 simple_backups, 223 224 /* Make numbered backups of files that already have numbered backups, 225 and simple backups of the others. */ 226 numbered_existing_backups, 227 228 /* Make numbered backups of every file. */ 229 numbered_backups 230 }; 231 232 /* Two tables describing arguments (keys) and their corresponding 233 values */ 234 static const char *const backup_args[] = 235 { 236 "no", "none", "off", 237 "simple", "never", 238 "existing", "nil", 239 "numbered", "t", 240 0 241 }; 242 243 static const enum backup_type backup_vals[] = 244 { 245 no_backups, no_backups, no_backups, 246 simple_backups, simple_backups, 247 numbered_existing_backups, numbered_existing_backups, 248 numbered_backups, numbered_backups 249 }; 250 251 int 252 main (int argc, const char *const *argv) 253 { 254 const char *cp; 255 enum backup_type backup_type = no_backups; 256 257 program_name = (char *) argv[0]; 258 259 if (argc > 2) 260 { 261 fprintf (stderr, "Usage: %s [VERSION_CONTROL]\n", program_name); 262 exit (1); 263 } 264 265 if ((cp = getenv ("VERSION_CONTROL"))) 266 backup_type = XARGMATCH ("$VERSION_CONTROL", cp, 267 backup_args, backup_vals); 268 269 if (argc == 2) 270 backup_type = XARGMATCH (program_name, argv[1], 271 backup_args, backup_vals); 272 273 printf ("The version control is '%s'\n", 274 ARGMATCH_TO_ARGUMENT (backup_type, backup_args, backup_vals)); 275 276 return 0; 277 } 278 #endif 279
