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-object-private.hh" 35#include "hb-unicode-private.hh" 36 37 38#ifndef HB_BUFFER_MAX_EXPANSION_FACTOR 39#define HB_BUFFER_MAX_EXPANSION_FACTOR 32 40#endif 41#ifndef HB_BUFFER_MAX_LEN_MIN 42#define HB_BUFFER_MAX_LEN_MIN 8192 43#endif 44#ifndef HB_BUFFER_MAX_LEN_DEFAULT 45#define HB_BUFFER_MAX_LEN_DEFAULT 0x3FFFFFFF /* Shaping more than a billion chars? Let us know! */ 46#endif 47 48ASSERT_STATIC (sizeof (hb_glyph_info_t) == 20); 49ASSERT_STATIC (sizeof (hb_glyph_info_t) == sizeof (hb_glyph_position_t)); 50 51HB_MARK_AS_FLAG_T (hb_buffer_flags_t); 52HB_MARK_AS_FLAG_T (hb_buffer_serialize_flags_t); 53 54enum hb_buffer_scratch_flags_t { 55 HB_BUFFER_SCRATCH_FLAG_DEFAULT = 0x00000000u, 56 HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII = 0x00000001u, 57 HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES = 0x00000002u, 58 HB_BUFFER_SCRATCH_FLAG_HAS_SPACE_FALLBACK = 0x00000004u, 59 HB_BUFFER_SCRATCH_FLAG_HAS_GPOS_ATTACHMENT = 0x00000008u, 60 /* Reserved for complex shapers' internal use. */ 61 HB_BUFFER_SCRATCH_FLAG_COMPLEX0 = 0x01000000u, 62 HB_BUFFER_SCRATCH_FLAG_COMPLEX1 = 0x02000000u, 63 HB_BUFFER_SCRATCH_FLAG_COMPLEX2 = 0x04000000u, 64 HB_BUFFER_SCRATCH_FLAG_COMPLEX3 = 0x08000000u, 65}; 66HB_MARK_AS_FLAG_T (hb_buffer_scratch_flags_t); 67 68 69/* 70 * hb_buffer_t 71 */ 72 73struct hb_buffer_t { 74 hb_object_header_t header; 75 ASSERT_POD (); 76 77 /* Information about how the text in the buffer should be treated */ 78 hb_unicode_funcs_t *unicode; /* Unicode functions */ 79 hb_buffer_flags_t flags; /* BOT / EOT / etc. */ 80 hb_buffer_cluster_level_t cluster_level; 81 hb_codepoint_t replacement; /* U+FFFD or something else. */ 82 hb_buffer_scratch_flags_t scratch_flags; /* Have space-flallback, etc. */ 83 unsigned int max_len; /* Maximum allowed len. */ 84 85 /* Buffer contents */ 86 hb_buffer_content_type_t content_type; 87 hb_segment_properties_t props; /* Script, language, direction */ 88 89 bool in_error; /* Allocation failed */ 90 bool have_output; /* Whether we have an output buffer going on */ 91 bool have_positions; /* Whether we have positions */ 92 93 unsigned int idx; /* Cursor into ->info and ->pos arrays */ 94 unsigned int len; /* Length of ->info and ->pos arrays */ 95 unsigned int out_len; /* Length of ->out array if have_output */ 96 97 unsigned int allocated; /* Length of allocated arrays */ 98 hb_glyph_info_t *info; 99 hb_glyph_info_t *out_info; 100 hb_glyph_position_t *pos; 101 102 inline hb_glyph_info_t &cur (unsigned int i = 0) { return info[idx + i]; } 103 inline hb_glyph_info_t cur (unsigned int i = 0) const { return info[idx + i]; } 104 105 inline hb_glyph_position_t &cur_pos (unsigned int i = 0) { return pos[idx + i]; } 106 inline hb_glyph_position_t cur_pos (unsigned int i = 0) const { return pos[idx + i]; } 107 108 inline hb_glyph_info_t &prev (void) { return out_info[out_len ? out_len - 1 : 0]; } 109 inline hb_glyph_info_t prev (void) const { return out_info[out_len ? out_len - 1 : 0]; } 110 111 inline bool has_separate_output (void) const { return info != out_info; } 112 113 unsigned int serial; 114 115 /* Text before / after the main buffer contents. 116 * Always in Unicode, and ordered outward. 117 * Index 0 is for "pre-context", 1 for "post-context". */ 118 static const unsigned int CONTEXT_LENGTH = 5; 119 hb_codepoint_t context[2][CONTEXT_LENGTH]; 120 unsigned int context_len[2]; 121 122 /* Debugging API */ 123 hb_buffer_message_func_t message_func; 124 void *message_data; 125 hb_destroy_func_t message_destroy; 126 127 /* Internal debugging. */ 128 /* The bits here reflect current allocations of the bytes in glyph_info_t's var1 and var2. */ 129#ifndef HB_NDEBUG 130 uint8_t allocated_var_bits; 131#endif 132 inline void allocate_var (unsigned int start, unsigned int count) 133 { 134#ifndef HB_NDEBUG 135 unsigned int end = start + count; 136 assert (end <= 8); 137 unsigned int bits = (1<<end) - (1<<start); 138 assert (0 == (allocated_var_bits & bits)); 139 allocated_var_bits |= bits; 140#endif 141 } 142 inline void deallocate_var (unsigned int start, unsigned int count) 143 { 144#ifndef HB_NDEBUG 145 unsigned int end = start + count; 146 assert (end <= 8); 147 unsigned int bits = (1<<end) - (1<<start); 148 assert (bits == (allocated_var_bits & bits)); 149 allocated_var_bits &= ~bits; 150#endif 151 } 152 inline void assert_var (unsigned int start, unsigned int count) 153 { 154#ifndef HB_NDEBUG 155 unsigned int end = start + count; 156 assert (end <= 8); 157 unsigned int bits = (1<<end) - (1<<start); 158 assert (bits == (allocated_var_bits & bits)); 159#endif 160 } 161 inline void deallocate_var_all (void) 162 { 163#ifndef HB_NDEBUG 164 allocated_var_bits = 0; 165#endif 166 } 167 168 169 /* Methods */ 170 171 HB_INTERNAL void reset (void); 172 HB_INTERNAL void clear (void); 173 174 inline unsigned int backtrack_len (void) const 175 { return have_output? out_len : idx; } 176 inline unsigned int lookahead_len (void) const 177 { return len - idx; } 178 inline unsigned int next_serial (void) { return serial++; } 179 180 HB_INTERNAL void add (hb_codepoint_t codepoint, 181 unsigned int cluster); 182 HB_INTERNAL void add_info (const hb_glyph_info_t &glyph_info); 183 184 HB_INTERNAL void reverse_range (unsigned int start, unsigned int end); 185 HB_INTERNAL void reverse (void); 186 HB_INTERNAL void reverse_clusters (void); 187 HB_INTERNAL void guess_segment_properties (void); 188 189 HB_INTERNAL void swap_buffers (void); 190 HB_INTERNAL void remove_output (void); 191 HB_INTERNAL void clear_output (void); 192 HB_INTERNAL void clear_positions (void); 193 194 HB_INTERNAL void replace_glyphs (unsigned int num_in, 195 unsigned int num_out, 196 const hb_codepoint_t *glyph_data); 197 198 HB_INTERNAL void replace_glyph (hb_codepoint_t glyph_index); 199 /* Makes a copy of the glyph at idx to output and replace glyph_index */ 200 HB_INTERNAL void output_glyph (hb_codepoint_t glyph_index); 201 HB_INTERNAL void output_info (const hb_glyph_info_t &glyph_info); 202 /* Copies glyph at idx to output but doesn't advance idx */ 203 HB_INTERNAL void copy_glyph (void); 204 HB_INTERNAL bool move_to (unsigned int i); /* i is output-buffer index. */ 205 /* Copies glyph at idx to output and advance idx. 206 * If there's no output, just advance idx. */ 207 inline void 208 next_glyph (void) 209 { 210 if (have_output) 211 { 212 if (unlikely (out_info != info || out_len != idx)) { 213 if (unlikely (!make_room_for (1, 1))) return; 214 out_info[out_len] = info[idx]; 215 } 216 out_len++; 217 } 218 219 idx++; 220 } 221 222 /* Advance idx without copying to output. */ 223 inline void skip_glyph (void) { idx++; } 224 225 inline void reset_masks (hb_mask_t mask) 226 { 227 for (unsigned int j = 0; j < len; j++) 228 info[j].mask = mask; 229 } 230 inline void add_masks (hb_mask_t mask) 231 { 232 for (unsigned int j = 0; j < len; j++) 233 info[j].mask |= mask; 234 } 235 HB_INTERNAL void set_masks (hb_mask_t value, 236 hb_mask_t mask, 237 unsigned int cluster_start, 238 unsigned int cluster_end); 239 240 HB_INTERNAL void merge_clusters (unsigned int start, 241 unsigned int end) 242 { 243 if (end - start < 2) 244 return; 245 merge_clusters_impl (start, end); 246 } 247 HB_INTERNAL void merge_clusters_impl (unsigned int start, 248 unsigned int end); 249 HB_INTERNAL void merge_out_clusters (unsigned int start, 250 unsigned int end); 251 /* Merge clusters for deleting current glyph, and skip it. */ 252 HB_INTERNAL void delete_glyph (void); 253 254 /* Internal methods */ 255 HB_INTERNAL bool enlarge (unsigned int size); 256 257 inline bool ensure (unsigned int size) 258 { return likely (!size || size < allocated) ? true : enlarge (size); } 259 260 inline bool ensure_inplace (unsigned int size) 261 { return likely (!size || size < allocated); } 262 263 HB_INTERNAL bool make_room_for (unsigned int num_in, unsigned int num_out); 264 HB_INTERNAL bool shift_forward (unsigned int count); 265 266 typedef long scratch_buffer_t; 267 HB_INTERNAL scratch_buffer_t *get_scratch_buffer (unsigned int *size); 268 269 inline void clear_context (unsigned int side) { context_len[side] = 0; } 270 271 HB_INTERNAL void sort (unsigned int start, unsigned int end, int(*compar)(const hb_glyph_info_t *, const hb_glyph_info_t *)); 272 273 inline bool messaging (void) { return unlikely (message_func); } 274 inline bool message (hb_font_t *font, const char *fmt, ...) HB_PRINTF_FUNC(3, 4) 275 { 276 if (!messaging ()) 277 return true; 278 va_list ap; 279 va_start (ap, fmt); 280 bool ret = message_impl (font, fmt, ap); 281 va_end (ap); 282 return ret; 283 } 284 HB_INTERNAL bool message_impl (hb_font_t *font, const char *fmt, va_list ap) HB_PRINTF_FUNC(3, 0); 285}; 286 287 288#define HB_BUFFER_XALLOCATE_VAR(b, func, var) \ 289 b->func (offsetof (hb_glyph_info_t, var) - offsetof(hb_glyph_info_t, var1), \ 290 sizeof (b->info[0].var)) 291#define HB_BUFFER_ALLOCATE_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, allocate_var, var ()) 292#define HB_BUFFER_DEALLOCATE_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, deallocate_var, var ()) 293#define HB_BUFFER_ASSERT_VAR(b, var) HB_BUFFER_XALLOCATE_VAR (b, assert_var, var ()) 294 295 296#endif /* HB_BUFFER_PRIVATE_HH */ 297