hb-buffer-private.hh revision 0bc7a38463bfb37f12efeb1b8cb2024cf4a347bc
1/* 2 * Copyright © 1998-2004 David Turner and Werner Lemberg 3 * Copyright © 2004,2007,2009,2010 Red Hat, Inc. 4 * Copyright © 2011,2012 Google, Inc. 5 * 6 * This is part of HarfBuzz, a text shaping library. 7 * 8 * Permission is hereby granted, without written agreement and without 9 * license or royalty fees, to use, copy, modify, and distribute this 10 * software and its documentation for any purpose, provided that the 11 * above copyright notice and the following two paragraphs appear in 12 * all copies of this software. 13 * 14 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 15 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 17 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 18 * DAMAGE. 19 * 20 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 21 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 22 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 23 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 24 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 25 * 26 * Red Hat Author(s): Owen Taylor, Behdad Esfahbod 27 * Google Author(s): Behdad Esfahbod 28 */ 29 30#ifndef HB_BUFFER_PRIVATE_HH 31#define HB_BUFFER_PRIVATE_HH 32 33#include "hb-private.hh" 34#include "hb-buffer.h" 35#include "hb-object-private.hh" 36#include "hb-unicode-private.hh" 37 38 39 40ASSERT_STATIC (sizeof (hb_glyph_info_t) == 20); 41ASSERT_STATIC (sizeof (hb_glyph_info_t) == sizeof (hb_glyph_position_t)); 42 43 44/* 45 * hb_segment_properties_t 46 */ 47 48typedef struct hb_segment_properties_t { 49 hb_direction_t direction; 50 hb_script_t script; 51 hb_language_t language; 52 ASSERT_POD (); 53} hb_segment_properties_t; 54 55#define _HB_BUFFER_PROPS_DEFAULT { HB_DIRECTION_INVALID, HB_SCRIPT_INVALID, HB_LANGUAGE_INVALID } 56 57static inline hb_bool_t 58hb_segment_properties_equal (const hb_segment_properties_t *a, 59 const hb_segment_properties_t *b) 60{ 61 return a->direction == b->direction && 62 a->script == b->script && 63 a->language == b->language; 64} 65 66 67#if 0 68static inline unsigned int 69hb_segment_properties_hash (const hb_segment_properties_t *p) 70{ 71 /* TODO improve */ 72 return (unsigned int) p->direction + 73 (unsigned int) p->script + 74 (intptr_t) (p->language); 75} 76#endif 77 78 79 80/* 81 * hb_buffer_t 82 */ 83 84struct hb_buffer_t { 85 hb_object_header_t header; 86 ASSERT_POD (); 87 88 /* Information about how the text in the buffer should be treated */ 89 90 hb_unicode_funcs_t *unicode; /* Unicode functions */ 91 hb_segment_properties_t props; /* Script, language, direction */ 92 93 /* Buffer contents */ 94 95 hb_buffer_content_type_t content_type; 96 97 bool in_error; /* Allocation failed */ 98 bool have_output; /* Whether we have an output buffer going on */ 99 bool have_positions; /* Whether we have positions */ 100 101 unsigned int idx; /* Cursor into ->info and ->pos arrays */ 102 unsigned int len; /* Length of ->info and ->pos arrays */ 103 unsigned int out_len; /* Length of ->out array if have_output */ 104 105 unsigned int allocated; /* Length of allocated arrays */ 106 hb_glyph_info_t *info; 107 hb_glyph_info_t *out_info; 108 hb_glyph_position_t *pos; 109 110 inline hb_glyph_info_t &cur (unsigned int i = 0) { return info[idx + i]; } 111 inline hb_glyph_info_t cur (unsigned int i = 0) const { return info[idx + i]; } 112 113 inline hb_glyph_position_t &cur_pos (unsigned int i = 0) { return pos[idx + i]; } 114 inline hb_glyph_position_t cur_pos (unsigned int i = 0) const { return pos[idx + i]; } 115 116 inline hb_glyph_info_t &prev (void) { return out_info[out_len - 1]; } 117 inline hb_glyph_info_t prev (void) const { return info[out_len - 1]; } 118 119 unsigned int serial; 120 121 /* These reflect current allocations of the bytes in glyph_info_t's var1 and var2. */ 122 uint8_t allocated_var_bytes[8]; 123 const char *allocated_var_owner[8]; 124 125 /* Text before / after the main buffer contents. 126 * Always in Unicode, and ordered outward. 127 * Index 0 is for "pre-context", 1 for "post-context". */ 128 static const unsigned int CONTEXT_LENGTH = 5; 129 hb_codepoint_t context[2][CONTEXT_LENGTH]; 130 unsigned int context_len[2]; 131 132 133 /* Methods */ 134 135 HB_INTERNAL void reset (void); 136 137 inline unsigned int backtrack_len (void) const 138 { return have_output? out_len : idx; } 139 inline unsigned int next_serial (void) { return serial++; } 140 141 HB_INTERNAL void allocate_var (unsigned int byte_i, unsigned int count, const char *owner); 142 HB_INTERNAL void deallocate_var (unsigned int byte_i, unsigned int count, const char *owner); 143 HB_INTERNAL void assert_var (unsigned int byte_i, unsigned int count, const char *owner); 144 HB_INTERNAL void deallocate_var_all (void); 145 146 HB_INTERNAL void add (hb_codepoint_t codepoint, 147 hb_mask_t mask, 148 unsigned int cluster); 149 150 HB_INTERNAL void reverse_range (unsigned int start, unsigned int end); 151 HB_INTERNAL void reverse (void); 152 HB_INTERNAL void reverse_clusters (void); 153 HB_INTERNAL void guess_properties (void); 154 155 HB_INTERNAL void swap_buffers (void); 156 HB_INTERNAL void remove_output (void); 157 HB_INTERNAL void clear_output (void); 158 HB_INTERNAL void clear_positions (void); 159 160 HB_INTERNAL void replace_glyphs (unsigned int num_in, 161 unsigned int num_out, 162 const hb_codepoint_t *glyph_data); 163 164 HB_INTERNAL void replace_glyph (hb_codepoint_t glyph_index); 165 /* Makes a copy of the glyph at idx to output and replace glyph_index */ 166 HB_INTERNAL void output_glyph (hb_codepoint_t glyph_index); 167 HB_INTERNAL void output_info (hb_glyph_info_t &glyph_info); 168 /* Copies glyph at idx to output but doesn't advance idx */ 169 HB_INTERNAL void copy_glyph (void); 170 /* Copies glyph at idx to output and advance idx. 171 * If there's no output, just advance idx. */ 172 inline void 173 next_glyph (void) 174 { 175 if (have_output) 176 { 177 if (unlikely (out_info != info || out_len != idx)) { 178 if (unlikely (!make_room_for (1, 1))) return; 179 out_info[out_len] = info[idx]; 180 } 181 out_len++; 182 } 183 184 idx++; 185 } 186 187 /* Advance idx without copying to output. */ 188 inline void skip_glyph (void) { idx++; } 189 190 inline void reset_masks (hb_mask_t mask) 191 { 192 for (unsigned int j = 0; j < len; j++) 193 info[j].mask = mask; 194 } 195 inline void add_masks (hb_mask_t mask) 196 { 197 for (unsigned int j = 0; j < len; j++) 198 info[j].mask |= mask; 199 } 200 HB_INTERNAL void set_masks (hb_mask_t value, 201 hb_mask_t mask, 202 unsigned int cluster_start, 203 unsigned int cluster_end); 204 205 HB_INTERNAL void merge_clusters (unsigned int start, 206 unsigned int end); 207 HB_INTERNAL void merge_out_clusters (unsigned int start, 208 unsigned int end); 209 210 /* Internal methods */ 211 HB_INTERNAL bool enlarge (unsigned int size); 212 213 inline bool ensure (unsigned int size) 214 { return likely (size < allocated) ? true : enlarge (size); } 215 216 HB_INTERNAL bool make_room_for (unsigned int num_in, unsigned int num_out); 217 218 HB_INTERNAL void *get_scratch_buffer (unsigned int *size); 219 220 inline void clear_context (unsigned int side) { context_len[side] = 0; } 221}; 222 223 224#define HB_BUFFER_XALLOCATE_VAR(b, func, var, owner) \ 225 b->func (offsetof (hb_glyph_info_t, var) - offsetof(hb_glyph_info_t, var1), \ 226 sizeof (b->info[0].var), owner) 227#define HB_BUFFER_ALLOCATE_VAR(b, var) \ 228 HB_BUFFER_XALLOCATE_VAR (b, allocate_var, var (), #var) 229#define HB_BUFFER_DEALLOCATE_VAR(b, var) \ 230 HB_BUFFER_XALLOCATE_VAR (b, deallocate_var, var (), #var) 231#define HB_BUFFER_ASSERT_VAR(b, var) \ 232 HB_BUFFER_XALLOCATE_VAR (b, assert_var, var (), #var) 233 234 235#endif /* HB_BUFFER_PRIVATE_HH */ 236