base/string.c

   1 /*
   2  * Copyright (c) 2010 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Portions Copyright (c) 2010 Apple Inc. All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  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  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "baselocl.h"
  37 #include <string.h>
  38
  39 static void
  40 string_dealloc(void *ptr)
  41 {
  42 }
  43
  44 static int
  45 string_cmp(void *a, void *b)
  46 {
  47     return strcmp(a, b);
  48 }
  49
  50 static unsigned long
  51 string_hash(void *ptr)
  52 {
  53     const char *s = ptr;
  54     unsigned long n;
  55
  56     for (n = 0; *s; ++s)
  57         n += *s;
  58     return n;
  59 }
  60
  61 struct heim_type_data _heim_string_object = {
  62     HEIM_TID_STRING,
  63     "string-object",
  64     NULL,
  65     string_dealloc,
  66     NULL,
  67     string_cmp,
  68     string_hash
  69 };
  70
  71 /**
  72  * Create a string object
  73  *
  74  * @param string the string to create, must be an utf8 string
  75  *
  76  * @return string object
  77  */
  78
  79 heim_string_t
  80 heim_string_create(const char *string)
  81 {
  82     return heim_string_create_with_bytes(string, strlen(string));
  83 }
  84
  85 heim_string_t
  86 heim_string_create_with_bytes(const void *data, size_t len)
  87 {
  88     heim_string_t s;
  89
  90     s = _heim_alloc_object(&_heim_string_object, len + 1);
  91     if (s) {
  92         memcpy(s, data, len);
  93         ((char *)s)[len] = '\0';
  94     }
  95     return s;
  96 }
  97
  98 /**
  99  * Return the type ID of string objects
 100  *
 101  * @return type id of string objects
 102  */
 103
 104 heim_tid_t
 105 heim_string_get_type_id(void)
 106 {
 107     return HEIM_TID_STRING;
 108 }
 109
 110 /**
 111  * Get the string value of the content.
 112  *
 113  * @param string the string object to get the value from
 114  *
 115  * @return a utf8 string
 116  */
 117
 118 const char *
 119 heim_string_get_utf8(heim_string_t string)
 120 {
 121     return (const char *)string;
 122 }
 123
 124 /*
 125  *
 126  */
 127
 128 static void
 129 init_string(void *ptr)
 130 {
 131     heim_dict_t *dict = ptr;
 132     *dict = heim_dict_create(101);
 133     heim_assert(*dict != NULL, "__heim_string_constant");
 134 }
 135
 136 heim_string_t
 137 __heim_string_constant(const char *_str)
 138 {
 139     static HEIMDAL_MUTEX mutex = HEIMDAL_MUTEX_INITIALIZER;
 140     static heim_base_once_t once;
 141     static heim_dict_t dict = NULL;
 142     heim_string_t s, s2;
 143
 144     heim_base_once_f(&once, &dict, init_string);
 145     s = heim_string_create(_str);
 146
 147     HEIMDAL_MUTEX_lock(&mutex);
 148     s2 = heim_dict_get_value(dict, s);
 149     if (s2) {
 150         heim_release(s);
 151         s = s2;
 152     } else {
 153         _heim_make_permanent(s);
 154         heim_dict_set_value(dict, s, s);
 155     }
 156     HEIMDAL_MUTEX_unlock(&mutex);
 157
 158     return s;
 159 }