1/* argmatch.c -- find a match for a string in an array 2 3 Copyright (C) 1990, 1998, 1999, 2001, 2002, 2003, 2004, 2005 Free 4 Software 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 2, or (at your option) 9 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, write to the Free Software Foundation, 18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20/* Written by David MacKenzie <djm@ai.mit.edu> 21 Modified by Akim Demaille <demaille@inf.enst.fr> */ 22 23#ifdef HAVE_CONFIG_H 24# include <config.h> 25#endif 26 27/* Specification. */ 28#include "argmatch.h" 29 30#include <stdbool.h> 31#include <stdio.h> 32#include <stdlib.h> 33#include <string.h> 34 35#include "gettext.h" 36#define _(msgid) gettext (msgid) 37 38#include "error.h" 39#include "exit.h" 40#include "quotearg.h" 41#include "quote.h" 42 43#if USE_UNLOCKED_IO 44# include "unlocked-io.h" 45#endif 46 47/* When reporting an invalid argument, show nonprinting characters 48 by using the quoting style ARGMATCH_QUOTING_STYLE. Do not use 49 literal_quoting_style. */ 50#ifndef ARGMATCH_QUOTING_STYLE 51# define ARGMATCH_QUOTING_STYLE locale_quoting_style 52#endif 53 54/* Non failing version of argmatch call this function after failing. */ 55#ifndef ARGMATCH_DIE 56# include "exitfail.h" 57# define ARGMATCH_DIE exit (exit_failure) 58#endif 59 60#ifdef ARGMATCH_DIE_DECL 61ARGMATCH_DIE_DECL; 62#endif 63 64static void 65__argmatch_die (void) 66{ 67 ARGMATCH_DIE; 68} 69 70/* Used by XARGMATCH and XARGCASEMATCH. See description in argmatch.h. 71 Default to __argmatch_die, but allow caller to change this at run-time. */ 72argmatch_exit_fn argmatch_die = __argmatch_die; 73 74 75/* If ARG is an unambiguous match for an element of the 76 NULL-terminated array ARGLIST, return the index in ARGLIST 77 of the matched element, else -1 if it does not match any element 78 or -2 if it is ambiguous (is a prefix of more than one element). 79 80 If VALLIST is none null, use it to resolve ambiguities limited to 81 synonyms, i.e., for 82 "yes", "yop" -> 0 83 "no", "nope" -> 1 84 "y" is a valid argument, for `0', and "n" for `1'. */ 85 86ptrdiff_t 87argmatch (const char *arg, const char *const *arglist, 88 const char *vallist, size_t valsize) 89{ 90 size_t i; /* Temporary index in ARGLIST. */ 91 size_t arglen; /* Length of ARG. */ 92 ptrdiff_t matchind = -1; /* Index of first nonexact match. */ 93 bool ambiguous = false; /* If true, multiple nonexact match(es). */ 94 95 arglen = strlen (arg); 96 97 /* Test all elements for either exact match or abbreviated matches. */ 98 for (i = 0; arglist[i]; i++) 99 { 100 if (!strncmp (arglist[i], arg, arglen)) 101 { 102 if (strlen (arglist[i]) == arglen) 103 /* Exact match found. */ 104 return i; 105 else if (matchind == -1) 106 /* First nonexact match found. */ 107 matchind = i; 108 else 109 { 110 /* Second nonexact match found. */ 111 if (vallist == NULL 112 || memcmp (vallist + valsize * matchind, 113 vallist + valsize * i, valsize)) 114 { 115 /* There is a real ambiguity, or we could not 116 disambiguate. */ 117 ambiguous = true; 118 } 119 } 120 } 121 } 122 if (ambiguous) 123 return -2; 124 else 125 return matchind; 126} 127 128/* Error reporting for argmatch. 129 CONTEXT is a description of the type of entity that was being matched. 130 VALUE is the invalid value that was given. 131 PROBLEM is the return value from argmatch. */ 132 133void 134argmatch_invalid (const char *context, const char *value, ptrdiff_t problem) 135{ 136 char const *format = (problem == -1 137 ? _("invalid argument %s for %s") 138 : _("ambiguous argument %s for %s")); 139 140 error (0, 0, format, quotearg_n_style (0, ARGMATCH_QUOTING_STYLE, value), 141 quote_n (1, context)); 142} 143 144/* List the valid arguments for argmatch. 145 ARGLIST is the same as in argmatch. 146 VALLIST is a pointer to an array of values. 147 VALSIZE is the size of the elements of VALLIST */ 148void 149argmatch_valid (const char *const *arglist, 150 const char *vallist, size_t valsize) 151{ 152 size_t i; 153 const char *last_val = NULL; 154 155 /* We try to put synonyms on the same line. The assumption is that 156 synonyms follow each other */ 157 fprintf (stderr, _("Valid arguments are:")); 158 for (i = 0; arglist[i]; i++) 159 if ((i == 0) 160 || memcmp (last_val, vallist + valsize * i, valsize)) 161 { 162 fprintf (stderr, "\n - `%s'", arglist[i]); 163 last_val = vallist + valsize * i; 164 } 165 else 166 { 167 fprintf (stderr, ", `%s'", arglist[i]); 168 } 169 putc ('\n', stderr); 170} 171 172/* Never failing versions of the previous functions. 173 174 CONTEXT is the context for which argmatch is called (e.g., 175 "--version-control", or "$VERSION_CONTROL" etc.). Upon failure, 176 calls the (supposed never to return) function EXIT_FN. */ 177 178ptrdiff_t 179__xargmatch_internal (const char *context, 180 const char *arg, const char *const *arglist, 181 const char *vallist, size_t valsize, 182 argmatch_exit_fn exit_fn) 183{ 184 ptrdiff_t res = argmatch (arg, arglist, vallist, valsize); 185 if (res >= 0) 186 /* Success. */ 187 return res; 188 189 /* We failed. Explain why. */ 190 argmatch_invalid (context, arg, res); 191 argmatch_valid (arglist, vallist, valsize); 192 (*exit_fn) (); 193 194 return -1; /* To please the compilers. */ 195} 196 197/* Look for VALUE in VALLIST, an array of objects of size VALSIZE and 198 return the first corresponding argument in ARGLIST */ 199const char * 200argmatch_to_argument (const char *value, 201 const char *const *arglist, 202 const char *vallist, size_t valsize) 203{ 204 size_t i; 205 206 for (i = 0; arglist[i]; i++) 207 if (!memcmp (value, vallist + valsize * i, valsize)) 208 return arglist[i]; 209 return NULL; 210} 211 212#ifdef TEST 213/* 214 * Based on "getversion.c" by David MacKenzie <djm@gnu.ai.mit.edu> 215 */ 216char *program_name; 217 218/* When to make backup files. */ 219enum backup_type 220{ 221 /* Never make backups. */ 222 no_backups, 223 224 /* Make simple backups of every file. */ 225 simple_backups, 226 227 /* Make numbered backups of files that already have numbered backups, 228 and simple backups of the others. */ 229 numbered_existing_backups, 230 231 /* Make numbered backups of every file. */ 232 numbered_backups 233}; 234 235/* Two tables describing arguments (keys) and their corresponding 236 values */ 237static const char *const backup_args[] = 238{ 239 "no", "none", "off", 240 "simple", "never", 241 "existing", "nil", 242 "numbered", "t", 243 0 244}; 245 246static const enum backup_type backup_vals[] = 247{ 248 no_backups, no_backups, no_backups, 249 simple_backups, simple_backups, 250 numbered_existing_backups, numbered_existing_backups, 251 numbered_backups, numbered_backups 252}; 253 254int 255main (int argc, const char *const *argv) 256{ 257 const char *cp; 258 enum backup_type backup_type = no_backups; 259 260 program_name = (char *) argv[0]; 261 262 if (argc > 2) 263 { 264 fprintf (stderr, "Usage: %s [VERSION_CONTROL]\n", program_name); 265 exit (1); 266 } 267 268 if ((cp = getenv ("VERSION_CONTROL"))) 269 backup_type = XARGMATCH ("$VERSION_CONTROL", cp, 270 backup_args, backup_vals); 271 272 if (argc == 2) 273 backup_type = XARGMATCH (program_name, argv[1], 274 backup_args, backup_vals); 275 276 printf ("The version control is `%s'\n", 277 ARGMATCH_TO_ARGUMENT (backup_type, backup_args, backup_vals)); 278 279 return 0; 280} 281#endif 282