harfbuzz/src/hb-ot-post-table.hh

300 lines
8.7 KiB
C++

/*
* Copyright © 2016 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
*/
#ifndef HB_OT_POST_TABLE_HH
#define HB_OT_POST_TABLE_HH
#include "hb-open-type.hh"
#define HB_STRING_ARRAY_NAME format1_names
#define HB_STRING_ARRAY_LIST "hb-ot-post-macroman.hh"
#include "hb-string-array.hh"
#undef HB_STRING_ARRAY_LIST
#undef HB_STRING_ARRAY_NAME
#define NUM_FORMAT1_NAMES 258
/*
* post -- PostScript
* https://docs.microsoft.com/en-us/typography/opentype/spec/post
*/
#define HB_OT_TAG_post HB_TAG('p','o','s','t')
namespace OT {
struct postV2Tail
{
friend struct post;
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (glyphNameIndex.sanitize (c));
}
protected:
ArrayOf<HBUINT16> glyphNameIndex; /* This is not an offset, but is the
* ordinal number of the glyph in 'post'
* string tables. */
/*UnsizedArrayOf<HBUINT8>
namesX;*/ /* Glyph names with length bytes [variable]
* (a Pascal string). */
public:
DEFINE_SIZE_ARRAY (2, glyphNameIndex);
};
struct post
{
static constexpr hb_tag_t tableTag = HB_OT_TAG_post;
bool subset (hb_subset_plan_t *plan) const
{
unsigned int post_prime_length;
hb_blob_t *post_blob = hb_sanitize_context_t ().reference_table<post>(plan->source);
hb_blob_t *post_prime_blob = hb_blob_create_sub_blob (post_blob, 0, post::min_size);
post *post_prime = (post *) hb_blob_get_data_writable (post_prime_blob, &post_prime_length);
hb_blob_destroy (post_blob);
if (unlikely (!post_prime || post_prime_length != post::min_size))
{
hb_blob_destroy (post_prime_blob);
DEBUG_MSG(SUBSET, nullptr, "Invalid source post table with length %d.", post_prime_length);
return false;
}
post_prime->version.major.set (3); // Version 3 does not have any glyph names.
bool result = plan->add_table (HB_OT_TAG_post, post_prime_blob);
hb_blob_destroy (post_prime_blob);
return result;
}
struct accelerator_t
{
void init (hb_face_t *face)
{
index_to_offset.init ();
table = hb_sanitize_context_t ().reference_table<post> (face);
unsigned int table_length = table.get_length ();
version = table->version.to_int ();
if (version != 0x00020000) return;
const postV2Tail &v2 = table->v2X;
glyphNameIndex = &v2.glyphNameIndex;
pool = &StructAfter<uint8_t> (v2.glyphNameIndex);
const uint8_t *end = (const uint8_t *) (const void *) table + table_length;
for (const uint8_t *data = pool;
index_to_offset.length < 65535 && data < end && data + *data < end;
data += 1 + *data)
index_to_offset.push (data - pool);
}
void fini ()
{
index_to_offset.fini ();
free (gids_sorted_by_name.get ());
table.destroy ();
}
bool get_glyph_name (hb_codepoint_t glyph,
char *buf, unsigned int buf_len) const
{
hb_bytes_t s = find_glyph_name (glyph);
if (!s.length) return false;
if (!buf_len) return true;
unsigned int len = MIN (buf_len - 1, s.length);
strncpy (buf, s.arrayZ, len);
buf[len] = '\0';
return true;
}
bool get_glyph_from_name (const char *name, int len,
hb_codepoint_t *glyph) const
{
unsigned int count = get_glyph_count ();
if (unlikely (!count)) return false;
if (len < 0) len = strlen (name);
if (unlikely (!len)) return false;
retry:
uint16_t *gids = gids_sorted_by_name.get ();
if (unlikely (!gids))
{
gids = (uint16_t *) malloc (count * sizeof (gids[0]));
if (unlikely (!gids))
return false; /* Anything better?! */
for (unsigned int i = 0; i < count; i++)
gids[i] = i;
hb_sort_r (gids, count, sizeof (gids[0]), cmp_gids, (void *) this);
if (unlikely (!gids_sorted_by_name.cmpexch (nullptr, gids)))
{
free (gids);
goto retry;
}
}
hb_bytes_t st (name, len);
const uint16_t *gid = (const uint16_t *) hb_bsearch_r (hb_addressof (st), gids, count,
sizeof (gids[0]), cmp_key, (void *) this);
if (gid)
{
*glyph = *gid;
return true;
}
return false;
}
protected:
unsigned int get_glyph_count () const
{
if (version == 0x00010000)
return NUM_FORMAT1_NAMES;
if (version == 0x00020000)
return glyphNameIndex->len;
return 0;
}
static int cmp_gids (const void *pa, const void *pb, void *arg)
{
const accelerator_t *thiz = (const accelerator_t *) arg;
uint16_t a = * (const uint16_t *) pa;
uint16_t b = * (const uint16_t *) pb;
return thiz->find_glyph_name (b).cmp (thiz->find_glyph_name (a));
}
static int cmp_key (const void *pk, const void *po, void *arg)
{
const accelerator_t *thiz = (const accelerator_t *) arg;
const hb_bytes_t *key = (const hb_bytes_t *) pk;
uint16_t o = * (const uint16_t *) po;
return thiz->find_glyph_name (o).cmp (*key);
}
hb_bytes_t find_glyph_name (hb_codepoint_t glyph) const
{
if (version == 0x00010000)
{
if (glyph >= NUM_FORMAT1_NAMES)
return hb_bytes_t ();
return format1_names (glyph);
}
if (version != 0x00020000 || glyph >= glyphNameIndex->len)
return hb_bytes_t ();
unsigned int index = glyphNameIndex->arrayZ[glyph];
if (index < NUM_FORMAT1_NAMES)
return format1_names (index);
index -= NUM_FORMAT1_NAMES;
if (index >= index_to_offset.length)
return hb_bytes_t ();
unsigned int offset = index_to_offset[index];
const uint8_t *data = pool + offset;
unsigned int name_length = *data;
data++;
return hb_bytes_t ((const char *) data, name_length);
}
private:
hb_blob_ptr_t<post> table;
uint32_t version;
const ArrayOf<HBUINT16> *glyphNameIndex;
hb_vector_t<uint32_t> index_to_offset;
const uint8_t *pool;
hb_atomic_ptr_t<uint16_t *> gids_sorted_by_name;
};
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (likely (c->check_struct (this) &&
(version.to_int () == 0x00010000 ||
(version.to_int () == 0x00020000 && v2X.sanitize (c)) ||
version.to_int () == 0x00030000)));
}
public:
FixedVersion<>version; /* 0x00010000 for version 1.0
* 0x00020000 for version 2.0
* 0x00025000 for version 2.5 (deprecated)
* 0x00030000 for version 3.0 */
Fixed italicAngle; /* Italic angle in counter-clockwise degrees
* from the vertical. Zero for upright text,
* negative for text that leans to the right
* (forward). */
FWORD underlinePosition; /* This is the suggested distance of the top
* of the underline from the baseline
* (negative values indicate below baseline).
* The PostScript definition of this FontInfo
* dictionary key (the y coordinate of the
* center of the stroke) is not used for
* historical reasons. The value of the
* PostScript key may be calculated by
* subtracting half the underlineThickness
* from the value of this field. */
FWORD underlineThickness; /* Suggested values for the underline
thickness. */
HBUINT32 isFixedPitch; /* Set to 0 if the font is proportionally
* spaced, non-zero if the font is not
* proportionally spaced (i.e. monospaced). */
HBUINT32 minMemType42; /* Minimum memory usage when an OpenType font
* is downloaded. */
HBUINT32 maxMemType42; /* Maximum memory usage when an OpenType font
* is downloaded. */
HBUINT32 minMemType1; /* Minimum memory usage when an OpenType font
* is downloaded as a Type 1 font. */
HBUINT32 maxMemType1; /* Maximum memory usage when an OpenType font
* is downloaded as a Type 1 font. */
postV2Tail v2X;
DEFINE_SIZE_MIN (32);
};
struct post_accelerator_t : post::accelerator_t {};
} /* namespace OT */
#endif /* HB_OT_POST_TABLE_HH */