glib/gcompletion.c

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 /*
  28  * MT safe
  29  */
  30
  31 #include "config.h"
  32
  33 #include <string.h>
  34
  35 #include "glib.h"
  36 #include "galias.h"
  37
  38 static void completion_check_cache (GCompletion* cmp,
  39                                     gchar**      new_prefix);
  40
  41 GCompletion*
  42 g_completion_new (GCompletionFunc func)
  43 {
  44   GCompletion* gcomp;
  45
  46   gcomp = g_new (GCompletion, 1);
  47   gcomp->items = NULL;
  48   gcomp->cache = NULL;
  49   gcomp->prefix = NULL;
  50   gcomp->func = func;
  51   gcomp->strncmp_func = strncmp;
  52
  53   return gcomp;
  54 }
  55
  56 void
  57 g_completion_add_items (GCompletion* cmp,
  58                         GList*       items)
  59 {
  60   GList* it;
  61
  62   g_return_if_fail (cmp != NULL);
  63
  64   /* optimize adding to cache? */
  65   if (cmp->cache)
  66     {
  67       g_list_free (cmp->cache);
  68       cmp->cache = NULL;
  69     }
  70
  71   if (cmp->prefix)
  72     {
  73       g_free (cmp->prefix);
  74       cmp->prefix = NULL;
  75     }
  76
  77   it = items;
  78   while (it)
  79     {
  80       cmp->items = g_list_prepend (cmp->items, it->data);
  81       it = it->next;
  82     }
  83 }
  84
  85 void
  86 g_completion_remove_items (GCompletion* cmp,
  87                            GList*       items)
  88 {
  89   GList* it;
  90
  91   g_return_if_fail (cmp != NULL);
  92
  93   it = items;
  94   while (cmp->items && it)
  95     {
  96       cmp->items = g_list_remove (cmp->items, it->data);
  97       it = it->next;
  98     }
  99
 100   it = items;
 101   while (cmp->cache && it)
 102     {
 103       cmp->cache = g_list_remove(cmp->cache, it->data);
 104       it = it->next;
 105     }
 106 }
 107
 108 void
 109 g_completion_clear_items (GCompletion* cmp)
 110 {
 111   g_return_if_fail (cmp != NULL);
 112
 113   g_list_free (cmp->items);
 114   cmp->items = NULL;
 115   g_list_free (cmp->cache);
 116   cmp->cache = NULL;
 117   g_free (cmp->prefix);
 118   cmp->prefix = NULL;
 119 }
 120
 121 static void
 122 completion_check_cache (GCompletion* cmp,
 123                         gchar**      new_prefix)
 124 {
 125   register GList* list;
 126   register gsize len;
 127   register gsize i;
 128   register gsize plen;
 129   gchar* postfix;
 130   gchar* s;
 131
 132   if (!new_prefix)
 133     return;
 134   if (!cmp->cache)
 135     {
 136       *new_prefix = NULL;
 137       return;
 138     }
 139
 140   len = strlen(cmp->prefix);
 141   list = cmp->cache;
 142   s = cmp->func ? cmp->func (list->data) : (gchar*) list->data;
 143   postfix = s + len;
 144   plen = strlen (postfix);
 145   list = list->next;
 146
 147   while (list && plen)
 148     {
 149       s = cmp->func ? cmp->func (list->data) : (gchar*) list->data;
 150       s += len;
 151       for (i = 0; i < plen; ++i)
 152         {
 153           if (postfix[i] != s[i])
 154             break;
 155         }
 156       plen = i;
 157       list = list->next;
 158     }
 159
 160   *new_prefix = g_new0 (gchar, len + plen + 1);
 161   strncpy (*new_prefix, cmp->prefix, len);
 162   strncpy (*new_prefix + len, postfix, plen);
 163 }
 164
 165 /**
 166  * g_completion_complete_utf8:
 167  * @cmp: the #GCompletion
 168  * @prefix: the prefix string, typically used by the user, which is compared
 169  *    with each of the items
 170  * @new_prefix: if non-%NULL, returns the longest prefix which is common to all
 171  *    items that matched @prefix, or %NULL if no items matched @prefix.
 172  *    This string should be freed when no longer needed.
 173  *
 174  * Attempts to complete the string @prefix using the #GCompletion target items.
 175  * In contrast to g_completion_complete(), this function returns the largest common
 176  * prefix that is a valid UTF-8 string, omitting a possible common partial
 177  * character.
 178  *
 179  * You should use this function instead of g_completion_complete() if your
 180  * items are UTF-8 strings.
 181  *
 182  * Return value: the list of items whose strings begin with @prefix. This should
 183  * not be changed.
 184  *
 185  * Since: 2.4
 186  **/
 187 GList*
 188 g_completion_complete_utf8 (GCompletion  *cmp,
 189                             const gchar  *prefix,
 190                             gchar       **new_prefix)
 191 {
 192   GList *list;
 193   gchar *p, *q;
 194
 195   list = g_completion_complete (cmp, prefix, new_prefix);
 196
 197   if (new_prefix && *new_prefix)
 198     {
 199       p = *new_prefix + strlen (*new_prefix);
 200       q = g_utf8_find_prev_char (*new_prefix, p);
 201
 202       switch (g_utf8_get_char_validated (q, p - q))
 203         {
 204         case (gunichar)-2:
 205         case (gunichar)-1:
 206           *q = 0;
 207           break;
 208         default: ;
 209         }
 210
 211     }
 212
 213   return list;
 214 }
 215
 216 GList*
 217 g_completion_complete (GCompletion* cmp,
 218                        const gchar* prefix,
 219                        gchar**      new_prefix)
 220 {
 221   gsize plen, len;
 222   gboolean done = FALSE;
 223   GList* list;
 224
 225   g_return_val_if_fail (cmp != NULL, NULL);
 226   g_return_val_if_fail (prefix != NULL, NULL);
 227
 228   len = strlen (prefix);
 229   if (cmp->prefix && cmp->cache)
 230     {
 231       plen = strlen (cmp->prefix);
 232       if (plen <= len && ! cmp->strncmp_func (prefix, cmp->prefix, plen))
 233         {
 234           /* use the cache */
 235           list = cmp->cache;
 236           while (list)
 237             {
 238               GList *next = list->next;
 239
 240               if (cmp->strncmp_func (prefix,
 241                                      cmp->func ? cmp->func (list->data) : (gchar*) list->data,
 242                                      len))
 243                 cmp->cache = g_list_delete_link (cmp->cache, list);
 244
 245               list = next;
 246             }
 247           done = TRUE;
 248         }
 249     }
 250
 251   if (!done)
 252     {
 253       /* normal code */
 254       g_list_free (cmp->cache);
 255       cmp->cache = NULL;
 256       list = cmp->items;
 257       while (*prefix && list)
 258         {
 259           if (!cmp->strncmp_func (prefix,
 260                         cmp->func ? cmp->func (list->data) : (gchar*) list->data,
 261                         len))
 262             cmp->cache = g_list_prepend (cmp->cache, list->data);
 263           list = list->next;
 264         }
 265     }
 266   if (cmp->prefix)
 267     {
 268       g_free (cmp->prefix);
 269       cmp->prefix = NULL;
 270     }
 271   if (cmp->cache)
 272     cmp->prefix = g_strdup (prefix);
 273   completion_check_cache (cmp, new_prefix);
 274
 275   return *prefix ? cmp->cache : cmp->items;
 276 }
 277
 278 void
 279 g_completion_free (GCompletion* cmp)
 280 {
 281   g_return_if_fail (cmp != NULL);
 282
 283   g_completion_clear_items (cmp);
 284   g_free (cmp);
 285 }
 286
 287 void
 288 g_completion_set_compare(GCompletion *cmp,
 289                          GCompletionStrncmpFunc strncmp_func)
 290 {
 291   cmp->strncmp_func = strncmp_func;
 292 }
 293
 294 #ifdef TEST_COMPLETION
 295 #include <stdio.h>
 296 int
 297 main (int   argc,
 298       char* argv[])
 299 {
 300   FILE *file;
 301   gchar buf[1024];
 302   GList *list;
 303   GList *result;
 304   GList *tmp;
 305   GCompletion *cmp;
 306   gint i;
 307   gchar *longp = NULL;
 308
 309   if (argc < 3)
 310     {
 311       g_warning ("Usage: %s filename prefix1 [prefix2 ...]\n", argv[0]);
 312       return 1;
 313     }
 314
 315   file = fopen (argv[1], "r");
 316   if (!file)
 317     {
 318       g_warning ("Cannot open %s\n", argv[1]);
 319       return 1;
 320     }
 321
 322   cmp = g_completion_new (NULL);
 323   list = g_list_alloc ();
 324   while (fgets (buf, 1024, file))
 325     {
 326       list->data = g_strdup (buf);
 327       g_completion_add_items (cmp, list);
 328     }
 329   fclose (file);
 330
 331   for (i = 2; i < argc; ++i)
 332     {
 333       printf ("COMPLETING: %s\n", argv[i]);
 334       result = g_completion_complete (cmp, argv[i], &longp);
 335       g_list_foreach (result, (GFunc) printf, NULL);
 336       printf ("LONG MATCH: %s\n", longp);
 337       g_free (longp);
 338       longp = NULL;
 339     }
 340
 341   g_list_foreach (cmp->items, (GFunc) g_free, NULL);
 342   g_completion_free (cmp);
 343   g_list_free (list);
 344
 345   return 0;
 346 }
 347 #endif
 348
 349 #define __G_COMPLETION_C__
 350 #include "galiasdef.c"