common/lib/libprop/prop_string.c

   1 /*      $NetBSD: prop_string.c,v 1.11 2008/08/03 04:00:12 thorpej Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2006 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jason R. Thorpe.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <prop/prop_string.h>
  33 #include "prop_object_impl.h"
  34
  35 struct _prop_string {
  36         struct _prop_object     ps_obj;
  37         union {
  38                 char *          psu_mutable;
  39                 const char *    psu_immutable;
  40         } ps_un;
  41 #define ps_mutable              ps_un.psu_mutable
  42 #define ps_immutable            ps_un.psu_immutable
  43         size_t                  ps_size;        /* not including \0 */
  44         int                     ps_flags;
  45 };
  46
  47 #define PS_F_NOCOPY             0x01
  48
  49 _PROP_POOL_INIT(_prop_string_pool, sizeof(struct _prop_string), "propstng")
  50
  51 _PROP_MALLOC_DEFINE(M_PROP_STRING, "prop string",
  52                     "property string container object")
  53
  54 static _prop_object_free_rv_t
  55                 _prop_string_free(prop_stack_t, prop_object_t *);
  56 static bool     _prop_string_externalize(
  57                                 struct _prop_object_externalize_context *,
  58                                 void *);
  59 static _prop_object_equals_rv_t
  60                 _prop_string_equals(prop_object_t, prop_object_t,
  61                                     void **, void **,
  62                                     prop_object_t *, prop_object_t *);
  63
  64 static const struct _prop_object_type _prop_object_type_string = {
  65         .pot_type       =       PROP_TYPE_STRING,
  66         .pot_free       =       _prop_string_free,
  67         .pot_extern     =       _prop_string_externalize,
  68         .pot_equals     =       _prop_string_equals,
  69 };
  70
  71 #define prop_object_is_string(x)        \
  72         ((x) != NULL && (x)->ps_obj.po_type == &_prop_object_type_string)
  73 #define prop_string_contents(x)  ((x)->ps_immutable ? (x)->ps_immutable : "")
  74
  75 /* ARGSUSED */
  76 static _prop_object_free_rv_t
  77 _prop_string_free(prop_stack_t stack, prop_object_t *obj)
  78 {
  79         prop_string_t ps = *obj;
  80
  81         if ((ps->ps_flags & PS_F_NOCOPY) == 0 && ps->ps_mutable != NULL)
  82                 _PROP_FREE(ps->ps_mutable, M_PROP_STRING);
  83         _PROP_POOL_PUT(_prop_string_pool, ps);
  84
  85         return (_PROP_OBJECT_FREE_DONE);
  86 }
  87
  88 static bool
  89 _prop_string_externalize(struct _prop_object_externalize_context *ctx,
  90                          void *v)
  91 {
  92         prop_string_t ps = v;
  93
  94         if (ps->ps_size == 0)
  95                 return (_prop_object_externalize_empty_tag(ctx, "string"));
  96
  97         if (_prop_object_externalize_start_tag(ctx, "string") == false ||
  98             _prop_object_externalize_append_encoded_cstring(ctx,
  99                                                 ps->ps_immutable) == false ||
 100             _prop_object_externalize_end_tag(ctx, "string") == false)
 101                 return (false);
 102
 103         return (true);
 104 }
 105
 106 /* ARGSUSED */
 107 static _prop_object_equals_rv_t
 108 _prop_string_equals(prop_object_t v1, prop_object_t v2,
 109     void **stored_pointer1, void **stored_pointer2,
 110     prop_object_t *next_obj1, prop_object_t *next_obj2)
 111 {
 112         prop_string_t str1 = v1;
 113         prop_string_t str2 = v2;
 114
 115         if (str1 == str2)
 116                 return (_PROP_OBJECT_EQUALS_TRUE);
 117         if (str1->ps_size != str2->ps_size)
 118                 return (_PROP_OBJECT_EQUALS_FALSE);
 119         if (strcmp(prop_string_contents(str1), prop_string_contents(str2)))
 120                 return (_PROP_OBJECT_EQUALS_FALSE);
 121         else
 122                 return (_PROP_OBJECT_EQUALS_TRUE);
 123 }
 124
 125 static prop_string_t
 126 _prop_string_alloc(void)
 127 {
 128         prop_string_t ps;
 129
 130         ps = _PROP_POOL_GET(_prop_string_pool);
 131         if (ps != NULL) {
 132                 _prop_object_init(&ps->ps_obj, &_prop_object_type_string);
 133
 134                 ps->ps_mutable = NULL;
 135                 ps->ps_size = 0;
 136                 ps->ps_flags = 0;
 137         }
 138
 139         return (ps);
 140 }
 141
 142 /*
 143  * prop_string_create --
 144  *      Create an empty mutable string.
 145  */
 146 prop_string_t
 147 prop_string_create(void)
 148 {
 149
 150         return (_prop_string_alloc());
 151 }
 152
 153 /*
 154  * prop_string_create_cstring --
 155  *      Create a string that contains a copy of the provided C string.
 156  */
 157 prop_string_t
 158 prop_string_create_cstring(const char *str)
 159 {
 160         prop_string_t ps;
 161         char *cp;
 162         size_t len;
 163
 164         ps = _prop_string_alloc();
 165         if (ps != NULL) {
 166                 len = strlen(str);
 167                 cp = _PROP_MALLOC(len + 1, M_PROP_STRING);
 168                 if (cp == NULL) {
 169                         prop_object_release(ps);
 170                         return (NULL);
 171                 }
 172                 strcpy(cp, str);
 173                 ps->ps_mutable = cp;
 174                 ps->ps_size = len;
 175         }
 176         return (ps);
 177 }
 178
 179 /*
 180  * prop_string_create_cstring_nocopy --
 181  *      Create an immutable string that contains a refrence to the
 182  *      provided C string.
 183  */
 184 prop_string_t
 185 prop_string_create_cstring_nocopy(const char *str)
 186 {
 187         prop_string_t ps;
 188
 189         ps = _prop_string_alloc();
 190         if (ps != NULL) {
 191                 ps->ps_immutable = str;
 192                 ps->ps_size = strlen(str);
 193                 ps->ps_flags |= PS_F_NOCOPY;
 194         }
 195         return (ps);
 196 }
 197
 198 /*
 199  * prop_string_copy --
 200  *      Copy a string.  If the original string is immutable, then the
 201  *      copy is also immutable and references the same external data.
 202  */
 203 prop_string_t
 204 prop_string_copy(prop_string_t ops)
 205 {
 206         prop_string_t ps;
 207
 208         if (! prop_object_is_string(ops))
 209                 return (NULL);
 210
 211         ps = _prop_string_alloc();
 212         if (ps != NULL) {
 213                 ps->ps_size = ops->ps_size;
 214                 ps->ps_flags = ops->ps_flags;
 215                 if (ops->ps_flags & PS_F_NOCOPY)
 216                         ps->ps_immutable = ops->ps_immutable;
 217                 else {
 218                         char *cp = _PROP_MALLOC(ps->ps_size + 1, M_PROP_STRING);
 219                         if (cp == NULL) {
 220                                 prop_object_release(ps);
 221                                 return (NULL);
 222                         }
 223                         strcpy(cp, prop_string_contents(ops));
 224                         ps->ps_mutable = cp;
 225                 }
 226         }
 227         return (ps);
 228 }
 229
 230 /*
 231  * prop_string_copy_mutable --
 232  *      Copy a string, always returning a mutable copy.
 233  */
 234 prop_string_t
 235 prop_string_copy_mutable(prop_string_t ops)
 236 {
 237         prop_string_t ps;
 238         char *cp;
 239
 240         if (! prop_object_is_string(ops))
 241                 return (NULL);
 242
 243         ps = _prop_string_alloc();
 244         if (ps != NULL) {
 245                 ps->ps_size = ops->ps_size;
 246                 cp = _PROP_MALLOC(ps->ps_size + 1, M_PROP_STRING);
 247                 if (cp == NULL) {
 248                         prop_object_release(ps);
 249                         return (NULL);
 250                 }
 251                 strcpy(cp, prop_string_contents(ops));
 252                 ps->ps_mutable = cp;
 253         }
 254         return (ps);
 255 }
 256
 257 /*
 258  * prop_string_size --
 259  *      Return the size of the string, not including the terminating NUL.
 260  */
 261 size_t
 262 prop_string_size(prop_string_t ps)
 263 {
 264
 265         if (! prop_object_is_string(ps))
 266                 return (0);
 267
 268         return (ps->ps_size);
 269 }
 270
 271 /*
 272  * prop_string_mutable --
 273  *      Return true if the string is a mutable string.
 274  */
 275 bool
 276 prop_string_mutable(prop_string_t ps)
 277 {
 278
 279         if (! prop_object_is_string(ps))
 280                 return (false);
 281
 282         return ((ps->ps_flags & PS_F_NOCOPY) == 0);
 283 }
 284
 285 /*
 286  * prop_string_cstring --
 287  *      Return a copy of the contents of the string as a C string.
 288  *      The string is allocated with the M_TEMP malloc type.
 289  */
 290 char *
 291 prop_string_cstring(prop_string_t ps)
 292 {
 293         char *cp;
 294
 295         if (! prop_object_is_string(ps))
 296                 return (NULL);
 297
 298         cp = _PROP_MALLOC(ps->ps_size + 1, M_TEMP);
 299         if (cp != NULL)
 300                 strcpy(cp, prop_string_contents(ps));
 301
 302         return (cp);
 303 }
 304
 305 /*
 306  * prop_string_cstring_nocopy --
 307  *      Return an immutable reference to the contents of the string
 308  *      as a C string.
 309  */
 310 const char *
 311 prop_string_cstring_nocopy(prop_string_t ps)
 312 {
 313
 314         if (! prop_object_is_string(ps))
 315                 return (NULL);
 316
 317         return (prop_string_contents(ps));
 318 }
 319
 320 /*
 321  * prop_string_append --
 322  *      Append the contents of one string to another.  Returns true
 323  *      upon success.  The destination string must be mutable.
 324  */
 325 bool
 326 prop_string_append(prop_string_t dst, prop_string_t src)
 327 {
 328         char *ocp, *cp;
 329         size_t len;
 330
 331         if (! (prop_object_is_string(dst) &&
 332                prop_object_is_string(src)))
 333                 return (false);
 334
 335         if (dst->ps_flags & PS_F_NOCOPY)
 336                 return (false);
 337
 338         len = dst->ps_size + src->ps_size;
 339         cp = _PROP_MALLOC(len + 1, M_PROP_STRING);
 340         if (cp == NULL)
 341                 return (false);
 342         sprintf(cp, "%s%s", prop_string_contents(dst),
 343                 prop_string_contents(src));
 344         ocp = dst->ps_mutable;
 345         dst->ps_mutable = cp;
 346         dst->ps_size = len;
 347         if (ocp != NULL)
 348                 _PROP_FREE(ocp, M_PROP_STRING);
 349
 350         return (true);
 351 }
 352
 353 /*
 354  * prop_string_append_cstring --
 355  *      Append a C string to a string.  Returns true upon success.
 356  *      The destination string must be mutable.
 357  */
 358 bool
 359 prop_string_append_cstring(prop_string_t dst, const char *src)
 360 {
 361         char *ocp, *cp;
 362         size_t len;
 363
 364         if (! prop_object_is_string(dst))
 365                 return (false);
 366
 367         _PROP_ASSERT(src != NULL);
 368
 369         if (dst->ps_flags & PS_F_NOCOPY)
 370                 return (false);
 371
 372         len = dst->ps_size + strlen(src);
 373         cp = _PROP_MALLOC(len + 1, M_PROP_STRING);
 374         if (cp == NULL)
 375                 return (false);
 376         sprintf(cp, "%s%s", prop_string_contents(dst), src);
 377         ocp = dst->ps_mutable;
 378         dst->ps_mutable = cp;
 379         dst->ps_size = len;
 380         if (ocp != NULL)
 381                 _PROP_FREE(ocp, M_PROP_STRING);
 382
 383         return (true);
 384 }
 385
 386 /*
 387  * prop_string_equals --
 388  *      Return true if two strings are equivalent.
 389  */
 390 bool
 391 prop_string_equals(prop_string_t str1, prop_string_t str2)
 392 {
 393         if (!prop_object_is_string(str1) || !prop_object_is_string(str2))
 394                 return (false);
 395
 396         return prop_object_equals(str1, str2);
 397 }
 398
 399 /*
 400  * prop_string_equals_cstring --
 401  *      Return true if the string is equivalent to the specified
 402  *      C string.
 403  */
 404 bool
 405 prop_string_equals_cstring(prop_string_t ps, const char *cp)
 406 {
 407
 408         if (! prop_object_is_string(ps))
 409                 return (false);
 410
 411         return (strcmp(prop_string_contents(ps), cp) == 0);
 412 }
 413
 414 /*
 415  * _prop_string_internalize --
 416  *      Parse a <string>...</string> and return the object created from the
 417  *      external representation.
 418  */
 419 /* ARGSUSED */
 420 bool
 421 _prop_string_internalize(prop_stack_t stack, prop_object_t *obj,
 422     struct _prop_object_internalize_context *ctx)
 423 {
 424         prop_string_t string;
 425         char *str;
 426         size_t len, alen;
 427
 428         if (ctx->poic_is_empty_element) {
 429                 *obj = prop_string_create();
 430                 return (true);
 431         }
 432
 433         /* No attributes recognized here. */
 434         if (ctx->poic_tagattr != NULL)
 435                 return (true);
 436
 437         /* Compute the length of the result. */
 438         if (_prop_object_internalize_decode_string(ctx, NULL, 0, &len,
 439                                                    NULL) == false)
 440                 return (true);
 441
 442         str = _PROP_MALLOC(len + 1, M_PROP_STRING);
 443         if (str == NULL)
 444                 return (true);
 445
 446         if (_prop_object_internalize_decode_string(ctx, str, len, &alen,
 447                                                    &ctx->poic_cp) == false ||
 448             alen != len) {
 449                 _PROP_FREE(str, M_PROP_STRING);
 450                 return (true);
 451         }
 452         str[len] = '\0';
 453
 454         if (_prop_object_internalize_find_tag(ctx, "string",
 455                                               _PROP_TAG_TYPE_END) == false) {
 456                 _PROP_FREE(str, M_PROP_STRING);
 457                 return (true);
 458         }
 459
 460         string = _prop_string_alloc();
 461         if (string == NULL) {
 462                 _PROP_FREE(str, M_PROP_STRING);
 463                 return (true);
 464         }
 465
 466         string->ps_mutable = str;
 467         string->ps_size = len;
 468         *obj = string;
 469
 470         return (true);
 471 }