hb-common.c

   1 /*
   2 Port from c++ is protected by a GNU Lesser GPLv3
   3 Copyright © 2013 Sylvain BERTRAND <sylvain.bertrand@gmail.com>
   4                                   <sylware@legeek.net>
   5 */
   6 #define _GNU_SOURCE
   7 #include <string.h>
   8 #include <stdlib.h>
   9
  10 #include "hb.h"
  11 #include "hb-private.h"
  12 #include "hb-atomic-private.h"
  13
  14 /*this is actually hb_language_t type*/
  15 struct hb_language_impl_t {
  16         const char s[1];
  17 };
  18
  19 /*XXX:should go in lib "global init"*/
  20 static const char canon_map[256] = {
  21         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  22         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  23         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '-', 0, 0,
  24         '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 0, 0, 0, 0, 0, 0,
  25         '-', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
  26             'n', 'o',
  27         'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 0, 0, 0, 0, '-',
  28         0, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
  29             'o',
  30         'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 0, 0, 0, 0, 0
  31 };
  32
  33 static hb_bool_t lang_equal(hb_language_t v1, const void *v2)
  34 {
  35         const unsigned char *p1;
  36         const unsigned char *p2;
  37
  38         p1 = (const unsigned char *)v1;
  39         p2 = (const unsigned char *)v2;
  40
  41         while (*p1 && *p1 == canon_map[*p2])
  42                 p1++, p2++;
  43         return *p1 == canon_map[*p2];
  44 }
  45
  46 struct hb_language_item_t {
  47         struct hb_language_item_t *next;
  48         hb_language_t lang;
  49 };
  50
  51 static hb_language_t lang_assign(const char *s)
  52 {
  53         unsigned char *p;
  54
  55         hb_language_t lang = (hb_language_t) strdup(s);
  56         for (p = (unsigned char *)lang; *p; p++)
  57                 *p = canon_map[*p];
  58         return lang;
  59 }
  60
  61 /*Thread-safe lock-free language list*/
  62
  63 static struct hb_language_item_t *lang_items;
  64
  65 static struct hb_language_item_t *language_item_find_or_insert(const char *key)
  66 {
  67         struct hb_language_item_t *first_lang_item =
  68             hb_atomic_ptr_get(&lang_items);
  69
  70         while (1) {
  71                 struct hb_language_item_t *lang_item;
  72
  73                 for (lang_item = first_lang_item; lang_item;
  74                      lang_item = lang_item->next)
  75                         if (lang_equal(lang_item->lang, key))
  76                                 return lang_item;
  77
  78                 /*Not found; allocate one. */
  79                 lang_item = calloc(1, sizeof(*lang_item));
  80                 if (!lang_item)
  81                         return NULL;
  82                 lang_item->next = first_lang_item;
  83                 lang_item->lang = lang_assign(key);
  84
  85                 if (hb_atomic_ptr_cmpexch
  86                     (&lang_items, &first_lang_item, &lang_item))
  87                         return lang_item;
  88                 free(lang_item);
  89         }
  90 }
  91
  92 hb_language_t hb_language_from_string(const char *str, int len)
  93 {
  94         struct hb_language_item_t *item;
  95
  96         if (!str || !len || !*str)
  97                 return HB_LANGUAGE_INVALID;
  98
  99         if (len >= 0) {
 100                 char strbuf[64];
 101
 102                 len = MIN(len, (int)sizeof(strbuf) - 1);
 103                 str = (char *)memcpy(strbuf, str, len);
 104                 strbuf[len] = '\0';
 105         }
 106
 107         item = language_item_find_or_insert(str);
 108         return item ? item->lang : HB_LANGUAGE_INVALID;
 109 }
 110
 111 hb_tag_t hb_tag_from_string(const char *str, int len)
 112 {
 113         char tag[4];
 114         unsigned i;
 115
 116         if (!str || !len || !*str)
 117                 return HB_TAG_NONE;
 118
 119         if (len < 0 || len > 4)
 120                 len = 4;
 121         for (i = 0; i < (unsigned)len && str[i]; ++i)
 122                 tag[i] = str[i];
 123         for (; i < 4; ++i)
 124                 tag[i] = ' ';
 125         return HB_TAG_CHAR4(tag);
 126 }
 127
 128 const char *hb_language_to_string(hb_language_t language)
 129 {
 130         /*This is actually NULL-safe! */
 131         return language->s;
 132 }
 133
 134 hb_bool_t hb_version_atleast(unsigned int major,unsigned int minor,unsigned int micro)
 135 {
 136   return HB_VERSION_ATLEAST(major,minor,micro);
 137 }