lib/svec.c

   1 /*
   2  * Copyright (c) 2008, 2009 Nicira Networks.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include <config.h>
  18 #include "svec.h"
  19 #include <assert.h>
  20 #include <ctype.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include "dynamic-string.h"
  24 #include "util.h"
  25
  26 #define THIS_MODULE VLM_svec
  27 #include "vlog.h"
  28
  29 void
  30 svec_init(struct svec *svec)
  31 {
  32     svec->names = NULL;
  33     svec->n = 0;
  34     svec->allocated = 0;
  35 }
  36
  37 void
  38 svec_clone(struct svec *svec, const struct svec *other)
  39 {
  40     svec_init(svec);
  41     svec_append(svec, other);
  42 }
  43
  44 void
  45 svec_destroy(struct svec *svec)
  46 {
  47     svec_clear(svec);
  48     free(svec->names);
  49 }
  50
  51 void
  52 svec_clear(struct svec *svec)
  53 {
  54     size_t i;
  55
  56     for (i = 0; i < svec->n; i++) {
  57         free(svec->names[i]);
  58     }
  59     svec->n = 0;
  60 }
  61
  62 void
  63 svec_add(struct svec *svec, const char *name)
  64 {
  65     svec_add_nocopy(svec, xstrdup(name));
  66 }
  67
  68 void
  69 svec_del(struct svec *svec, const char *name)
  70 {
  71     size_t offset;
  72
  73     offset = svec_find(svec, name);
  74     if (offset != SIZE_MAX) {
  75         free(svec->names[offset]);
  76         memmove(&svec->names[offset], &svec->names[offset + 1],
  77                 sizeof *svec->names * (svec->n - offset - 1));
  78         svec->n--;
  79     }
  80 }
  81
  82 static void
  83 svec_expand(struct svec *svec)
  84 {
  85     if (svec->n >= svec->allocated) {
  86         svec->names = x2nrealloc(svec->names, &svec->allocated,
  87                                  sizeof *svec->names);
  88     }
  89 }
  90
  91 void
  92 svec_add_nocopy(struct svec *svec, char *name)
  93 {
  94     svec_expand(svec);
  95     svec->names[svec->n++] = name;
  96 }
  97
  98 void
  99 svec_append(struct svec *svec, const struct svec *other)
 100 {
 101     size_t i;
 102     for (i = 0; i < other->n; i++) {
 103         svec_add(svec, other->names[i]);
 104     }
 105 }
 106
 107 void
 108 svec_terminate(struct svec *svec)
 109 {
 110     svec_expand(svec);
 111     svec->names[svec->n] = NULL;
 112 }
 113
 114 static int
 115 compare_strings(const void *a_, const void *b_)
 116 {
 117     char *const *a = a_;
 118     char *const *b = b_;
 119     return strcmp(*a, *b);
 120 }
 121
 122 void
 123 svec_sort(struct svec *svec)
 124 {
 125     qsort(svec->names, svec->n, sizeof *svec->names, compare_strings);
 126 }
 127
 128 void
 129 svec_sort_unique(struct svec *svec)
 130 {
 131     svec_sort(svec);
 132     svec_unique(svec);
 133 }
 134
 135 void
 136 svec_unique(struct svec *svec)
 137 {
 138     assert(svec_is_sorted(svec));
 139     if (svec->n > 1) {
 140         /* This algorithm is lazy and sub-optimal, but it's "obviously correct"
 141          * and asymptotically optimal . */
 142         struct svec tmp;
 143         size_t i;
 144
 145         svec_init(&tmp);
 146         svec_add(&tmp, svec->names[0]);
 147         for (i = 1; i < svec->n; i++) {
 148             if (strcmp(svec->names[i - 1], svec->names[i])) {
 149                 svec_add(&tmp, svec->names[i]);
 150             }
 151         }
 152         svec_swap(&tmp, svec);
 153         svec_destroy(&tmp);
 154     }
 155 }
 156
 157 void
 158 svec_compact(struct svec *svec)
 159 {
 160     size_t i, j;
 161
 162     for (i = j = 0; i < svec->n; i++) {
 163         if (svec->names[i] != NULL) {
 164             svec->names[j++] = svec->names[i];
 165         }
 166     }
 167     svec->n = j;
 168 }
 169
 170 void
 171 svec_diff(const struct svec *a, const struct svec *b,
 172           struct svec *a_only, struct svec *both, struct svec *b_only)
 173 {
 174     size_t i, j;
 175
 176     assert(svec_is_sorted(a));
 177     assert(svec_is_sorted(b));
 178     if (a_only) {
 179         svec_init(a_only);
 180     }
 181     if (both) {
 182         svec_init(both);
 183     }
 184     if (b_only) {
 185         svec_init(b_only);
 186     }
 187     for (i = j = 0; i < a->n && j < b->n; ) {
 188         int cmp = strcmp(a->names[i], b->names[j]);
 189         if (cmp < 0) {
 190             if (a_only) {
 191                 svec_add(a_only, a->names[i]);
 192             }
 193             i++;
 194         } else if (cmp > 0) {
 195             if (b_only) {
 196                 svec_add(b_only, b->names[j]);
 197             }
 198             j++;
 199         } else {
 200             if (both) {
 201                 svec_add(both, a->names[i]);
 202             }
 203             i++;
 204             j++;
 205         }
 206     }
 207     if (a_only) {
 208         for (; i < a->n; i++) {
 209             svec_add(a_only, a->names[i]);
 210         }
 211     }
 212     if (b_only) {
 213         for (; j < b->n; j++) {
 214             svec_add(b_only, b->names[j]);
 215         }
 216     }
 217 }
 218
 219 bool
 220 svec_contains(const struct svec *svec, const char *name)
 221 {
 222     return svec_find(svec, name) != SIZE_MAX;
 223 }
 224
 225 size_t
 226 svec_find(const struct svec *svec, const char *name)
 227 {
 228     char **p;
 229
 230     assert(svec_is_sorted(svec));
 231     p = bsearch(&name, svec->names, svec->n, sizeof *svec->names,
 232                 compare_strings);
 233     return p ? p - svec->names : SIZE_MAX;
 234 }
 235
 236 bool
 237 svec_is_sorted(const struct svec *svec)
 238 {
 239     size_t i;
 240
 241     for (i = 1; i < svec->n; i++) {
 242         if (strcmp(svec->names[i - 1], svec->names[i]) > 0) {
 243             return false;
 244         }
 245     }
 246     return true;
 247 }
 248
 249 bool
 250 svec_is_unique(const struct svec *svec)
 251 {
 252     return svec_get_duplicate(svec) == NULL;
 253 }
 254
 255 const char *
 256 svec_get_duplicate(const struct svec *svec)
 257 {
 258     assert(svec_is_sorted(svec));
 259     if (svec->n > 1) {
 260         size_t i;
 261         for (i = 1; i < svec->n; i++) {
 262             if (!strcmp(svec->names[i - 1], svec->names[i])) {
 263                 return svec->names[i];
 264             }
 265         }
 266     }
 267     return NULL;
 268 }
 269
 270 void
 271 svec_swap(struct svec *a, struct svec *b)
 272 {
 273     struct svec tmp = *a;
 274     *a = *b;
 275     *b = tmp;
 276 }
 277
 278 void
 279 svec_print(const struct svec *svec, const char *title)
 280 {
 281     size_t i;
 282
 283     printf("%s:\n", title);
 284     for (i = 0; i < svec->n; i++) {
 285         printf("\"%s\"\n", svec->names[i]);
 286     }
 287 }
 288
 289 /* Breaks 'words' into words at white space, respecting shell-like quoting
 290  * conventions, and appends the words to 'svec'. */
 291 void
 292 svec_parse_words(struct svec *svec, const char *words)
 293 {
 294     struct ds word = DS_EMPTY_INITIALIZER;
 295     const char *p, *q;
 296
 297     for (p = words; *p != '\0'; p = q) {
 298         int quote = 0;
 299
 300         while (isspace((unsigned char) *p)) {
 301             p++;
 302         }
 303         if (*p == '\0') {
 304             break;
 305         }
 306
 307         ds_clear(&word);
 308         for (q = p; *q != '\0'; q++) {
 309             if (*q == quote) {
 310                 quote = 0;
 311             } else if (*q == '\'' || *q == '"') {
 312                 quote = *q;
 313             } else if (*q == '\\' && (!quote || quote == '"')) {
 314                 q++;
 315                 if (*q == '\0') {
 316                     VLOG_WARN("%s: ends in trailing backslash", words);
 317                     break;
 318                 }
 319                 ds_put_char(&word, *q);
 320             } else if (isspace((unsigned char) *q) && !quote) {
 321                 q++;
 322                 break;
 323             } else {
 324                 ds_put_char(&word, *q);
 325             }
 326         }
 327         svec_add(svec, ds_cstr(&word));
 328         if (quote) {
 329             VLOG_WARN("%s: word ends inside quoted string", words);
 330         }
 331     }
 332     ds_destroy(&word);
 333 }
 334
 335 bool
 336 svec_equal(const struct svec *a, const struct svec *b)
 337 {
 338     size_t i;
 339
 340     if (a->n != b->n) {
 341         return false;
 342     }
 343     for (i = 0; i < a->n; i++) {
 344         if (strcmp(a->names[i], b->names[i])) {
 345             return false;
 346         }
 347     }
 348     return true;
 349 }
 350
 351 char *
 352 svec_join(const struct svec *svec,
 353           const char *delimiter, const char *terminator)
 354 {
 355     struct ds ds;
 356     size_t i;
 357
 358     ds_init(&ds);
 359     for (i = 0; i < svec->n; i++) {
 360         if (i) {
 361             ds_put_cstr(&ds, delimiter);
 362         }
 363         ds_put_cstr(&ds, svec->names[i]);
 364     }
 365     ds_put_cstr(&ds, terminator);
 366     return ds_cstr(&ds);
 367 }
 368
 369 /* Breaks 's' into tokens at any character in 'delimiters', and appends each
 370  * token to 'svec'.  Empty tokens are not added. */
 371 void
 372 svec_split(struct svec *svec, const char *s_, const char *delimiters)
 373 {
 374     char *s = xstrdup(s_);
 375     char *save_ptr = NULL;
 376     char *token;
 377
 378     for (token = strtok_r(s, delimiters, &save_ptr); token != NULL;
 379          token = strtok_r(NULL, delimiters, &save_ptr)) {
 380         svec_add(svec, token);
 381     }
 382     free(s);
 383 }
 384
 385 const char *
 386 svec_back(const struct svec *svec)
 387 {
 388     assert(svec->n);
 389     return svec->names[svec->n - 1];
 390 }
 391
 392 void
 393 svec_pop_back(struct svec *svec)
 394 {
 395     assert(svec->n);
 396     free(svec->names[--svec->n]);
 397 }