harfbuzz/src/hb-common.cc

419 lines
9.7 KiB
C++

/*
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2011,2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#include "hb-private.hh"
#include "hb-version.h"
#include "hb-mutex-private.hh"
#include "hb-object-private.hh"
#include <locale.h>
/* hb_tag_t */
hb_tag_t
hb_tag_from_string (const char *s, int len)
{
char tag[4];
unsigned int i;
if (!s || !len || !*s)
return HB_TAG_NONE;
if (len < 0 || len > 4)
len = 4;
for (i = 0; i < (unsigned) len && s[i]; i++)
tag[i] = s[i];
for (; i < 4; i++)
tag[i] = ' ';
return HB_TAG_CHAR4 (tag);
}
void
hb_tag_to_string (hb_tag_t tag, char *buf)
{
buf[0] = (char) (uint8_t) (tag >> 24);
buf[1] = (char) (uint8_t) (tag >> 16);
buf[2] = (char) (uint8_t) (tag >> 8);
buf[3] = (char) (uint8_t) (tag >> 0);
}
/* hb_direction_t */
const char direction_strings[][4] = {
"ltr",
"rtl",
"ttb",
"btt"
};
hb_direction_t
hb_direction_from_string (const char *str, int len)
{
if (unlikely (!str || !len || !*str))
return HB_DIRECTION_INVALID;
/* Lets match loosely: just match the first letter, such that
* all of "ltr", "left-to-right", etc work!
*/
char c = TOLOWER (str[0]);
for (unsigned int i = 0; i < ARRAY_LENGTH (direction_strings); i++)
if (c == direction_strings[i][0])
return (hb_direction_t) (HB_DIRECTION_LTR + i);
return HB_DIRECTION_INVALID;
}
const char *
hb_direction_to_string (hb_direction_t direction)
{
if (likely ((unsigned int) (direction - HB_DIRECTION_LTR)
< ARRAY_LENGTH (direction_strings)))
return direction_strings[direction - HB_DIRECTION_LTR];
return "invalid";
}
/* hb_language_t */
struct hb_language_impl_t {
const char s[1];
};
static const char canon_map[256] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, '-', 0, 0,
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 0, 0, 0, 0, 0, 0,
'-', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 0, 0, 0, 0, '-',
0, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 0, 0, 0, 0, 0
};
static hb_bool_t
lang_equal (hb_language_t v1,
const void *v2)
{
const unsigned char *p1 = (const unsigned char *) v1;
const unsigned char *p2 = (const unsigned char *) v2;
while (*p1 && *p1 == canon_map[*p2])
p1++, p2++;
return *p1 == canon_map[*p2];
}
#if 0
static unsigned int
lang_hash (const void *key)
{
const unsigned char *p = key;
unsigned int h = 0;
while (canon_map[*p])
{
h = (h << 5) - h + canon_map[*p];
p++;
}
return h;
}
#endif
struct hb_language_item_t {
struct hb_language_item_t *next;
hb_language_t lang;
inline bool operator == (const char *s) const {
return lang_equal (lang, s);
}
inline hb_language_item_t & operator = (const char *s) {
lang = (hb_language_t) strdup (s);
for (unsigned char *p = (unsigned char *) lang; *p; p++)
*p = canon_map[*p];
return *this;
}
void finish (void) { free (lang); }
};
/* Thread-safe lock-free language list */
static hb_language_item_t *langs;
static inline
void free_langs (void)
{
while (langs) {
hb_language_item_t *next = langs->next;
langs->finish ();
free (langs);
langs = next;
}
}
static hb_language_item_t *
lang_find_or_insert (const char *key)
{
retry:
hb_language_item_t *first_lang = (hb_language_item_t *) hb_atomic_ptr_get (&langs);
for (hb_language_item_t *lang = first_lang; lang; lang = lang->next)
if (*lang == key)
return lang;
/* Not found; allocate one. */
hb_language_item_t *lang = (hb_language_item_t *) calloc (1, sizeof (hb_language_item_t));
if (unlikely (!lang))
return NULL;
lang->next = first_lang;
*lang = key;
if (!hb_atomic_ptr_cmpexch (&langs, first_lang, lang)) {
free (lang);
goto retry;
}
#ifdef HAVE_ATEXIT
if (!first_lang)
atexit (free_langs); /* First person registers atexit() callback. */
#endif
return lang;
}
hb_language_t
hb_language_from_string (const char *str, int len)
{
if (!str || !len || !*str)
return HB_LANGUAGE_INVALID;
char strbuf[32];
if (len >= 0) {
len = MIN (len, (int) sizeof (strbuf) - 1);
str = (char *) memcpy (strbuf, str, len);
strbuf[len] = '\0';
}
hb_language_item_t *item = lang_find_or_insert (str);
return likely (item) ? item->lang : HB_LANGUAGE_INVALID;
}
const char *
hb_language_to_string (hb_language_t language)
{
/* This is actually NULL-safe! */
return language->s;
}
hb_language_t
hb_language_get_default (void)
{
static hb_language_t default_language = HB_LANGUAGE_INVALID;
hb_language_t language = (hb_language_t) hb_atomic_ptr_get (&default_language);
if (unlikely (language == HB_LANGUAGE_INVALID)) {
language = hb_language_from_string (setlocale (LC_CTYPE, NULL), -1);
hb_atomic_ptr_cmpexch (&default_language, HB_LANGUAGE_INVALID, language);
}
return default_language;
}
/* hb_script_t */
hb_script_t
hb_script_from_iso15924_tag (hb_tag_t tag)
{
if (unlikely (tag == HB_TAG_NONE))
return HB_SCRIPT_INVALID;
/* Be lenient, adjust case (one capital letter followed by three small letters) */
tag = (tag & 0xDFDFDFDF) | 0x00202020;
switch (tag) {
/* These graduated from the 'Q' private-area codes, but
* the old code is still aliased by Unicode, and the Qaai
* one in use by ICU. */
case HB_TAG('Q','a','a','i'): return HB_SCRIPT_INHERITED;
case HB_TAG('Q','a','a','c'): return HB_SCRIPT_COPTIC;
/* Script variants from http://unicode.org/iso15924/ */
case HB_TAG('C','y','r','s'): return HB_SCRIPT_CYRILLIC;
case HB_TAG('L','a','t','f'): return HB_SCRIPT_LATIN;
case HB_TAG('L','a','t','g'): return HB_SCRIPT_LATIN;
case HB_TAG('S','y','r','e'): return HB_SCRIPT_SYRIAC;
case HB_TAG('S','y','r','j'): return HB_SCRIPT_SYRIAC;
case HB_TAG('S','y','r','n'): return HB_SCRIPT_SYRIAC;
}
/* If it looks right, just use the tag as a script */
if (((uint32_t) tag & 0xE0E0E0E0) == 0x40606060)
return (hb_script_t) tag;
/* Otherwise, return unknown */
return HB_SCRIPT_UNKNOWN;
}
hb_script_t
hb_script_from_string (const char *s, int len)
{
return hb_script_from_iso15924_tag (hb_tag_from_string (s, len));
}
hb_tag_t
hb_script_to_iso15924_tag (hb_script_t script)
{
return (hb_tag_t) script;
}
hb_direction_t
hb_script_get_horizontal_direction (hb_script_t script)
{
/* http://goo.gl/x9ilM */
switch ((hb_tag_t) script)
{
/* Unicode-1.1 additions */
case HB_SCRIPT_ARABIC:
case HB_SCRIPT_HEBREW:
/* Unicode-3.0 additions */
case HB_SCRIPT_SYRIAC:
case HB_SCRIPT_THAANA:
/* Unicode-4.0 additions */
case HB_SCRIPT_CYPRIOT:
/* Unicode-4.1 additions */
case HB_SCRIPT_KHAROSHTHI:
/* Unicode-5.0 additions */
case HB_SCRIPT_PHOENICIAN:
case HB_SCRIPT_NKO:
/* Unicode-5.1 additions */
case HB_SCRIPT_LYDIAN:
/* Unicode-5.2 additions */
case HB_SCRIPT_AVESTAN:
case HB_SCRIPT_IMPERIAL_ARAMAIC:
case HB_SCRIPT_INSCRIPTIONAL_PAHLAVI:
case HB_SCRIPT_INSCRIPTIONAL_PARTHIAN:
case HB_SCRIPT_OLD_SOUTH_ARABIAN:
case HB_SCRIPT_OLD_TURKIC:
case HB_SCRIPT_SAMARITAN:
/* Unicode-6.0 additions */
case HB_SCRIPT_MANDAIC:
/* Unicode-6.1 additions */
case HB_SCRIPT_MEROITIC_CURSIVE:
case HB_SCRIPT_MEROITIC_HIEROGLYPHS:
return HB_DIRECTION_RTL;
}
return HB_DIRECTION_LTR;
}
/* hb_user_data_array_t */
bool
hb_user_data_array_t::set (hb_user_data_key_t *key,
void * data,
hb_destroy_func_t destroy,
hb_bool_t replace)
{
if (!key)
return false;
if (replace) {
if (!data && !destroy) {
items.remove (key, lock);
return true;
}
}
hb_user_data_item_t item = {key, data, destroy};
bool ret = !!items.replace_or_insert (item, lock, replace);
return ret;
}
void *
hb_user_data_array_t::get (hb_user_data_key_t *key)
{
hb_user_data_item_t item = {NULL };
return items.find (key, &item, lock) ? item.data : NULL;
}
/* hb_version */
void
hb_version (unsigned int *major,
unsigned int *minor,
unsigned int *micro)
{
*major = HB_VERSION_MAJOR;
*minor = HB_VERSION_MINOR;
*micro = HB_VERSION_MICRO;
}
const char *
hb_version_string (void)
{
return HB_VERSION_STRING;
}
hb_bool_t
hb_version_check (unsigned int major,
unsigned int minor,
unsigned int micro)
{
return HB_VERSION_CHECK (major, minor, micro);
}