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Diffstat (limited to 'thirdparty/harfbuzz/src/hb-buffer.hh')
| -rw-r--r-- | thirdparty/harfbuzz/src/hb-buffer.hh | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/thirdparty/harfbuzz/src/hb-buffer.hh b/thirdparty/harfbuzz/src/hb-buffer.hh new file mode 100644 index 0000000000..3420ba434a --- /dev/null +++ b/thirdparty/harfbuzz/src/hb-buffer.hh @@ -0,0 +1,451 @@ +/* + * Copyright © 1998-2004 David Turner and Werner Lemberg + * Copyright © 2004,2007,2009,2010 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): Owen Taylor, Behdad Esfahbod + * Google Author(s): Behdad Esfahbod + */ + +#ifndef HB_BUFFER_HH +#define HB_BUFFER_HH + +#include "hb.hh" +#include "hb-unicode.hh" + + +#ifndef HB_BUFFER_MAX_LEN_FACTOR +#define HB_BUFFER_MAX_LEN_FACTOR 32 +#endif +#ifndef HB_BUFFER_MAX_LEN_MIN +#define HB_BUFFER_MAX_LEN_MIN 8192 +#endif +#ifndef HB_BUFFER_MAX_LEN_DEFAULT +#define HB_BUFFER_MAX_LEN_DEFAULT 0x3FFFFFFF /* Shaping more than a billion chars? Let us know! */ +#endif + +#ifndef HB_BUFFER_MAX_OPS_FACTOR +#define HB_BUFFER_MAX_OPS_FACTOR 64 +#endif +#ifndef HB_BUFFER_MAX_OPS_MIN +#define HB_BUFFER_MAX_OPS_MIN 1024 +#endif +#ifndef HB_BUFFER_MAX_OPS_DEFAULT +#define HB_BUFFER_MAX_OPS_DEFAULT 0x1FFFFFFF /* Shaping more than a billion operations? Let us know! */ +#endif + +static_assert ((sizeof (hb_glyph_info_t) == 20), ""); +static_assert ((sizeof (hb_glyph_info_t) == sizeof (hb_glyph_position_t)), ""); + +HB_MARK_AS_FLAG_T (hb_buffer_flags_t); +HB_MARK_AS_FLAG_T (hb_buffer_serialize_flags_t); +HB_MARK_AS_FLAG_T (hb_buffer_diff_flags_t); + +enum hb_buffer_scratch_flags_t { + HB_BUFFER_SCRATCH_FLAG_DEFAULT = 0x00000000u, + HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII = 0x00000001u, + HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES = 0x00000002u, + HB_BUFFER_SCRATCH_FLAG_HAS_SPACE_FALLBACK = 0x00000004u, + HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT = 0x00000008u, + HB_BUFFER_SCRATCH_FLAG_HAS_UNSAFE_TO_BREAK = 0x00000010u, + HB_BUFFER_SCRATCH_FLAG_HAS_CGJ = 0x00000020u, + + /* Reserved for complex shapers' internal use. */ + HB_BUFFER_SCRATCH_FLAG_COMPLEX0 = 0x01000000u, + HB_BUFFER_SCRATCH_FLAG_COMPLEX1 = 0x02000000u, + HB_BUFFER_SCRATCH_FLAG_COMPLEX2 = 0x04000000u, + HB_BUFFER_SCRATCH_FLAG_COMPLEX3 = 0x08000000u, +}; +HB_MARK_AS_FLAG_T (hb_buffer_scratch_flags_t); + + +/* + * hb_buffer_t + */ + +struct hb_buffer_t +{ + hb_object_header_t header; + + /* Information about how the text in the buffer should be treated */ + hb_unicode_funcs_t *unicode; /* Unicode functions */ + hb_buffer_flags_t flags; /* BOT / EOT / etc. */ + hb_buffer_cluster_level_t cluster_level; + hb_codepoint_t replacement; /* U+FFFD or something else. */ + hb_codepoint_t invisible; /* 0 or something else. */ + hb_buffer_scratch_flags_t scratch_flags; /* Have space-fallback, etc. */ + unsigned int max_len; /* Maximum allowed len. */ + int max_ops; /* Maximum allowed operations. */ + + /* Buffer contents */ + hb_buffer_content_type_t content_type; + hb_segment_properties_t props; /* Script, language, direction */ + + bool successful; /* Allocations successful */ + bool have_output; /* Whether we have an output buffer going on */ + bool have_positions; /* Whether we have positions */ + + unsigned int idx; /* Cursor into ->info and ->pos arrays */ + unsigned int len; /* Length of ->info and ->pos arrays */ + unsigned int out_len; /* Length of ->out array if have_output */ + + unsigned int allocated; /* Length of allocated arrays */ + hb_glyph_info_t *info; + hb_glyph_info_t *out_info; + hb_glyph_position_t *pos; + + unsigned int serial; + + /* Text before / after the main buffer contents. + * Always in Unicode, and ordered outward. + * Index 0 is for "pre-context", 1 for "post-context". */ + static constexpr unsigned CONTEXT_LENGTH = 5u; + hb_codepoint_t context[2][CONTEXT_LENGTH]; + unsigned int context_len[2]; + + /* Debugging API */ +#ifndef HB_NO_BUFFER_MESSAGE + hb_buffer_message_func_t message_func; + void *message_data; + hb_destroy_func_t message_destroy; +#endif + + /* Internal debugging. */ + /* The bits here reflect current allocations of the bytes in glyph_info_t's var1 and var2. */ +#ifndef HB_NDEBUG + uint8_t allocated_var_bits; +#endif + + + /* Methods */ + + bool in_error () const { return !successful; } + + void allocate_var (unsigned int start, unsigned int count) + { +#ifndef HB_NDEBUG + unsigned int end = start + count; + assert (end <= 8); + unsigned int bits = (1u<<end) - (1u<<start); + assert (0 == (allocated_var_bits & bits)); + allocated_var_bits |= bits; +#endif + } + void deallocate_var (unsigned int start, unsigned int count) + { +#ifndef HB_NDEBUG + unsigned int end = start + count; + assert (end <= 8); + unsigned int bits = (1u<<end) - (1u<<start); + assert (bits == (allocated_var_bits & bits)); + allocated_var_bits &= ~bits; +#endif + } + void assert_var (unsigned int start, unsigned int count) + { +#ifndef HB_NDEBUG + unsigned int end = start + count; + assert (end <= 8); + unsigned int bits = (1u<<end) - (1u<<start); + assert (bits == (allocated_var_bits & bits)); +#endif + } + void deallocate_var_all () + { +#ifndef HB_NDEBUG + allocated_var_bits = 0; +#endif + } + + hb_glyph_info_t &cur (unsigned int i = 0) { return info[idx + i]; } + hb_glyph_info_t cur (unsigned int i = 0) const { return info[idx + i]; } + + hb_glyph_position_t &cur_pos (unsigned int i = 0) { return pos[idx + i]; } + hb_glyph_position_t cur_pos (unsigned int i = 0) const { return pos[idx + i]; } + + hb_glyph_info_t &prev () { return out_info[out_len ? out_len - 1 : 0]; } + hb_glyph_info_t prev () const { return out_info[out_len ? out_len - 1 : 0]; } + + bool has_separate_output () const { return info != out_info; } + + + HB_INTERNAL void reset (); + HB_INTERNAL void clear (); + + unsigned int backtrack_len () const { return have_output? out_len : idx; } + unsigned int lookahead_len () const { return len - idx; } + unsigned int next_serial () { return serial++; } + + HB_INTERNAL void add (hb_codepoint_t codepoint, + unsigned int cluster); + HB_INTERNAL void add_info (const hb_glyph_info_t &glyph_info); + + HB_INTERNAL void reverse_range (unsigned int start, unsigned int end); + HB_INTERNAL void reverse (); + HB_INTERNAL void reverse_clusters (); + HB_INTERNAL void guess_segment_properties (); + + HB_INTERNAL void swap_buffers (); + HB_INTERNAL void remove_output (); + HB_INTERNAL void clear_output (); + HB_INTERNAL void clear_positions (); + + HB_INTERNAL void replace_glyphs (unsigned int num_in, + unsigned int num_out, + const hb_codepoint_t *glyph_data); + + void replace_glyph (hb_codepoint_t glyph_index) + { + if (unlikely (out_info != info || out_len != idx)) { + if (unlikely (!make_room_for (1, 1))) return; + out_info[out_len] = info[idx]; + } + out_info[out_len].codepoint = glyph_index; + + idx++; + out_len++; + } + /* Makes a copy of the glyph at idx to output and replace glyph_index */ + hb_glyph_info_t & output_glyph (hb_codepoint_t glyph_index) + { + if (unlikely (!make_room_for (0, 1))) return Crap (hb_glyph_info_t); + + if (unlikely (idx == len && !out_len)) + return Crap (hb_glyph_info_t); + + out_info[out_len] = idx < len ? info[idx] : out_info[out_len - 1]; + out_info[out_len].codepoint = glyph_index; + + out_len++; + + return out_info[out_len - 1]; + } + void output_info (const hb_glyph_info_t &glyph_info) + { + if (unlikely (!make_room_for (0, 1))) return; + + out_info[out_len] = glyph_info; + + out_len++; + } + /* Copies glyph at idx to output but doesn't advance idx */ + void copy_glyph () + { + if (unlikely (!make_room_for (0, 1))) return; + + out_info[out_len] = info[idx]; + + out_len++; + } + /* Copies glyph at idx to output and advance idx. + * If there's no output, just advance idx. */ + void + next_glyph () + { + if (have_output) + { + if (out_info != info || out_len != idx) + { + if (unlikely (!make_room_for (1, 1))) return; + out_info[out_len] = info[idx]; + } + out_len++; + } + + idx++; + } + /* Copies n glyphs at idx to output and advance idx. + * If there's no output, just advance idx. */ + void + next_glyphs (unsigned int n) + { + if (have_output) + { + if (out_info != info || out_len != idx) + { + if (unlikely (!make_room_for (n, n))) return; + memmove (out_info + out_len, info + idx, n * sizeof (out_info[0])); + } + out_len += n; + } + + idx += n; + } + /* Advance idx without copying to output. */ + void skip_glyph () { idx++; } + void reset_masks (hb_mask_t mask) + { + for (unsigned int j = 0; j < len; j++) + info[j].mask = mask; + } + void add_masks (hb_mask_t mask) + { + for (unsigned int j = 0; j < len; j++) + info[j].mask |= mask; + } + HB_INTERNAL void set_masks (hb_mask_t value, hb_mask_t mask, + unsigned int cluster_start, unsigned int cluster_end); + + void merge_clusters (unsigned int start, unsigned int end) + { + if (end - start < 2) + return; + merge_clusters_impl (start, end); + } + HB_INTERNAL void merge_clusters_impl (unsigned int start, unsigned int end); + HB_INTERNAL void merge_out_clusters (unsigned int start, unsigned int end); + /* Merge clusters for deleting current glyph, and skip it. */ + HB_INTERNAL void delete_glyph (); + + void unsafe_to_break (unsigned int start, + unsigned int end) + { + if (end - start < 2) + return; + unsafe_to_break_impl (start, end); + } + HB_INTERNAL void unsafe_to_break_impl (unsigned int start, unsigned int end); + HB_INTERNAL void unsafe_to_break_from_outbuffer (unsigned int start, unsigned int end); + + + /* Internal methods */ + HB_INTERNAL bool move_to (unsigned int i); /* i is output-buffer index. */ + + HB_INTERNAL bool enlarge (unsigned int size); + + bool ensure (unsigned int size) + { return likely (!size || size < allocated) ? true : enlarge (size); } + + bool ensure_inplace (unsigned int size) + { return likely (!size || size < allocated); } + + HB_INTERNAL bool make_room_for (unsigned int num_in, unsigned int num_out); + HB_INTERNAL bool shift_forward (unsigned int count); + + typedef long scratch_buffer_t; + HB_INTERNAL scratch_buffer_t *get_scratch_buffer (unsigned int *size); + + void clear_context (unsigned int side) { context_len[side] = 0; } + + HB_INTERNAL void sort (unsigned int start, unsigned int end, int(*compar)(const hb_glyph_info_t *, const hb_glyph_info_t *)); + + bool messaging () + { +#ifdef HB_NO_BUFFER_MESSAGE + return false; +#else + return unlikely (message_func); +#endif + } + bool message (hb_font_t *font, const char *fmt, ...) HB_PRINTF_FUNC(3, 4) + { +#ifdef HB_NO_BUFFER_MESSAGE + return true; +#else + if (!messaging ()) + return true; + va_list ap; + va_start (ap, fmt); + bool ret = message_impl (font, fmt, ap); + va_end (ap); + return ret; +#endif + } + HB_INTERNAL bool message_impl (hb_font_t *font, const char *fmt, va_list ap) HB_PRINTF_FUNC(3, 0); + + static void + set_cluster (hb_glyph_info_t &inf, unsigned int cluster, unsigned int mask = 0) + { + if (inf.cluster != cluster) + { + if (mask & HB_GLYPH_FLAG_UNSAFE_TO_BREAK) + inf.mask |= HB_GLYPH_FLAG_UNSAFE_TO_BREAK; + else + inf.mask &= ~HB_GLYPH_FLAG_UNSAFE_TO_BREAK; + } + inf.cluster = cluster; + } + + unsigned int + _unsafe_to_break_find_min_cluster (const hb_glyph_info_t *infos, + unsigned int start, unsigned int end, + unsigned int cluster) const + { + for (unsigned int i = start; i < end; i++) + cluster = hb_min (cluster, infos[i].cluster); + return cluster; + } + void + _unsafe_to_break_set_mask (hb_glyph_info_t *infos, + unsigned int start, unsigned int end, + unsigned int cluster) + { + for (unsigned int i = start; i < end; i++) + if (cluster != infos[i].cluster) + { + scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_UNSAFE_TO_BREAK; + infos[i].mask |= HB_GLYPH_FLAG_UNSAFE_TO_BREAK; + } + } + + void unsafe_to_break_all () { unsafe_to_break_impl (0, len); } + void safe_to_break_all () + { + for (unsigned int i = 0; i < len; i++) + info[i].mask &= ~HB_GLYPH_FLAG_UNSAFE_TO_BREAK; + } +}; +DECLARE_NULL_INSTANCE (hb_buffer_t); + + +/* Loop over clusters. Duplicated in foreach_syllable(). */ +#define foreach_cluster(buffer, start, end) \ + for (unsigned int \ + _count = buffer->len, \ + start = 0, end = _count ? _next_cluster (buffer, 0) : 0; \ + start < _count; \ + start = end, end = _next_cluster (buffer, start)) + +static inline unsigned int +_next_cluster (hb_buffer_t *buffer, unsigned int start) +{ + hb_glyph_info_t *info = buffer->info; + unsigned int count = buffer->len; + + unsigned int cluster = info[start].cluster; + while (++start < count && cluster == info[start].cluster) + ; + + return start; +} + + +#define HB_BUFFER_XALLOCATE_VAR(b, func, var) \ + b->func (offsetof (hb_glyph_info_t, var) - offsetof(hb_glyph_info_t, var1), \ + sizeof (b->info[0].var)) +#define HB_BUFFER_ALLOCATE_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, allocate_var, var ()) +#define HB_BUFFER_DEALLOCATE_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, deallocate_var, var ()) +#define HB_BUFFER_ASSERT_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, assert_var, var ()) + + +#endif /* HB_BUFFER_HH */ |