diff options
Diffstat (limited to 'Build/source/libs/harfbuzz/harfbuzz-0.9.37/src/hb-shaper.cc')
-rw-r--r-- | Build/source/libs/harfbuzz/harfbuzz-0.9.37/src/hb-shaper.cc | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/Build/source/libs/harfbuzz/harfbuzz-0.9.37/src/hb-shaper.cc b/Build/source/libs/harfbuzz/harfbuzz-0.9.37/src/hb-shaper.cc new file mode 100644 index 00000000000..6ae26013821 --- /dev/null +++ b/Build/source/libs/harfbuzz/harfbuzz-0.9.37/src/hb-shaper.cc @@ -0,0 +1,109 @@ +/* + * Copyright © 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. + * + * Google Author(s): Behdad Esfahbod + */ + +#include "hb-private.hh" +#include "hb-shaper-private.hh" +#include "hb-atomic-private.hh" + + +static const hb_shaper_pair_t all_shapers[] = { +#define HB_SHAPER_IMPLEMENT(name) {#name, _hb_##name##_shape}, +#include "hb-shaper-list.hh" +#undef HB_SHAPER_IMPLEMENT +}; + + +/* Thread-safe, lock-free, shapers */ + +static const hb_shaper_pair_t *static_shapers; + +static inline +void free_static_shapers (void) +{ + if (unlikely (static_shapers != all_shapers)) + free ((void *) static_shapers); +} + +const hb_shaper_pair_t * +_hb_shapers_get (void) +{ +retry: + hb_shaper_pair_t *shapers = (hb_shaper_pair_t *) hb_atomic_ptr_get (&static_shapers); + + if (unlikely (!shapers)) + { + char *env = getenv ("HB_SHAPER_LIST"); + if (!env || !*env) { + (void) hb_atomic_ptr_cmpexch (&static_shapers, NULL, &all_shapers[0]); + return (const hb_shaper_pair_t *) all_shapers; + } + + /* Not found; allocate one. */ + shapers = (hb_shaper_pair_t *) malloc (sizeof (all_shapers)); + if (unlikely (!shapers)) { + (void) hb_atomic_ptr_cmpexch (&static_shapers, NULL, &all_shapers[0]); + return (const hb_shaper_pair_t *) all_shapers; + } + + memcpy (shapers, all_shapers, sizeof (all_shapers)); + + /* Reorder shaper list to prefer requested shapers. */ + unsigned int i = 0; + char *end, *p = env; + for (;;) { + end = strchr (p, ','); + if (!end) + end = p + strlen (p); + + for (unsigned int j = i; j < ARRAY_LENGTH (all_shapers); j++) + if (end - p == (int) strlen (shapers[j].name) && + 0 == strncmp (shapers[j].name, p, end - p)) + { + /* Reorder this shaper to position i */ + struct hb_shaper_pair_t t = shapers[j]; + memmove (&shapers[i + 1], &shapers[i], sizeof (shapers[i]) * (j - i)); + shapers[i] = t; + i++; + } + + if (!*end) + break; + else + p = end + 1; + } + + if (!hb_atomic_ptr_cmpexch (&static_shapers, NULL, shapers)) { + free (shapers); + goto retry; + } + +#ifdef HB_USE_ATEXIT + atexit (free_static_shapers); /* First person registers atexit() callback. */ +#endif + } + + return shapers; +} |