src/intervals.h

   1 /* Definitions and global variables for intervals.
   2    Copyright (C) 1993-1994, 2000-2012  Free Software Foundation, Inc.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software: you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation, either version 3 of the License, or
   9 (at your option) any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  18
  19 #include "dispextern.h"
  20
  21 INLINE_HEADER_BEGIN
  22
  23 /* Basic data type for use of intervals.  */
  24
  25 struct interval
  26 {
  27   /* The first group of entries deal with the tree structure.  */
  28
  29   ptrdiff_t total_length;       /* Length of myself and both children.  */
  30   ptrdiff_t position;           /* Cache of interval's character position.  */
  31                                 /* This field is usually updated
  32                                    simultaneously with an interval
  33                                    traversal, there is no guarantee
  34                                    that it is valid for a random
  35                                    interval.  */
  36   struct interval *left;        /* Intervals which precede me.  */
  37   struct interval *right;       /* Intervals which succeed me.  */
  38
  39   /* Parent in the tree, or the Lisp_Object containing this interval tree.  */
  40   union
  41   {
  42     struct interval *interval;
  43     Lisp_Object obj;
  44   } up;
  45   unsigned int up_obj : 1;
  46
  47   unsigned gcmarkbit : 1;
  48
  49   /* The remaining components are `properties' of the interval.
  50      The first four are duplicates for things which can be on the list,
  51      for purposes of speed.  */
  52
  53   unsigned int write_protect : 1;   /* Non-zero means can't modify.  */
  54   unsigned int visible : 1;         /* Zero means don't display.  */
  55   unsigned int front_sticky : 1;    /* Non-zero means text inserted just
  56                                        before this interval goes into it.  */
  57   unsigned int rear_sticky : 1;     /* Likewise for just after it.  */
  58   Lisp_Object plist;                /* Other properties.  */
  59 };
  60
  61 /* These are macros for dealing with the interval tree.  */
  62
  63 /* True if this interval has no right child.  */
  64 #define NULL_RIGHT_CHILD(i) ((i)->right == NULL)
  65
  66 /* True if this interval has no left child.  */
  67 #define NULL_LEFT_CHILD(i) ((i)->left == NULL)
  68
  69 /* True if this interval has no parent.  */
  70 #define NULL_PARENT(i) ((i)->up_obj || (i)->up.interval == 0)
  71
  72 /* True if this interval is the left child of some other interval.  */
  73 #define AM_LEFT_CHILD(i)                                        \
  74   (! NULL_PARENT (i) && INTERVAL_PARENT (i)->left == (i))
  75
  76 /* True if this interval is the right child of some other interval.  */
  77 #define AM_RIGHT_CHILD(i)                                       \
  78   (! NULL_PARENT (i) && INTERVAL_PARENT (i)->right == (i))
  79
  80 /* True if this interval has no children.  */
  81 #define LEAF_INTERVAL_P(i) ((i)->left == NULL && (i)->right == NULL)
  82
  83 /* True if this interval has no parent and is therefore the root.  */
  84 #define ROOT_INTERVAL_P(i) (NULL_PARENT (i))
  85
  86 /* True if this interval is the only interval in the interval tree.  */
  87 #define ONLY_INTERVAL_P(i) (ROOT_INTERVAL_P ((i)) && LEAF_INTERVAL_P ((i)))
  88
  89 /* True if this interval has both left and right children.  */
  90 #define BOTH_KIDS_P(i) ((i)->left != NULL && (i)->right != NULL)
  91
  92 /* The total size of all text represented by this interval and all its
  93    children in the tree.   This is zero if the interval is null.  */
  94 #define TOTAL_LENGTH(i) ((i) == NULL ? 0 : (i)->total_length)
  95
  96 /* The size of text represented by this interval alone.  */
  97 #define LENGTH(i) ((i) == NULL ? 0 : (TOTAL_LENGTH ((i))                \
  98                                       - TOTAL_LENGTH ((i)->right)       \
  99                                       - TOTAL_LENGTH ((i)->left)))
 100
 101 /* The position of the character just past the end of I.  Note that
 102    the position cache i->position must be valid for this to work.  */
 103 #define INTERVAL_LAST_POS(i) ((i)->position + LENGTH ((i)))
 104
 105 /* The total size of the left subtree of this interval.  */
 106 #define LEFT_TOTAL_LENGTH(i) ((i)->left ? (i)->left->total_length : 0)
 107
 108 /* The total size of the right subtree of this interval.  */
 109 #define RIGHT_TOTAL_LENGTH(i) ((i)->right ? (i)->right->total_length : 0)
 110
 111 /* These macros are for dealing with the interval properties.  */
 112
 113 /* True if this is a default interval, which is the same as being null
 114    or having no properties.  */
 115 #define DEFAULT_INTERVAL_P(i) (!i || EQ ((i)->plist, Qnil))
 116
 117 /* Test what type of parent we have.  Three possibilities: another
 118    interval, a buffer or string object, or NULL.  */
 119 #define INTERVAL_HAS_PARENT(i) ((i)->up_obj == 0 && (i)->up.interval != 0)
 120 #define INTERVAL_HAS_OBJECT(i) ((i)->up_obj)
 121
 122 /* Use these macros to get parent of an interval.
 123
 124    The choice of macros is dependent on the type needed.  Don't add
 125    casts to get around this, it will break some development work in
 126    progress.  */
 127
 128 #define INTERVAL_PARENT(i)                                      \
 129    (eassert ((i) != 0 && (i)->up_obj == 0), (i)->up.interval)
 130
 131 #define GET_INTERVAL_OBJECT(d,s) (eassert ((s)->up_obj == 1), (d) = (s)->up.obj)
 132
 133 /* Use these functions to set Lisp_Object
 134    or pointer slots of struct interval.  */
 135
 136 LISP_INLINE void
 137 interval_set_parent (INTERVAL i, INTERVAL parent)
 138 {
 139   i->up_obj = 0;
 140   i->up.interval = parent;
 141 }
 142
 143 LISP_INLINE void
 144 interval_set_object (INTERVAL i, Lisp_Object obj)
 145 {
 146   eassert (BUFFERP (obj) || STRINGP (obj));
 147   i->up_obj = 1;
 148   i->up.obj = obj;
 149 }
 150
 151 LISP_INLINE void
 152 interval_set_left (INTERVAL i, INTERVAL left)
 153 {
 154   i->left = left;
 155 }
 156
 157 LISP_INLINE void
 158 interval_set_right (INTERVAL i, INTERVAL right)
 159 {
 160   i->right = right;
 161 }
 162
 163 LISP_INLINE Lisp_Object
 164 interval_set_plist (INTERVAL i, Lisp_Object plist)
 165 {
 166   i->plist = plist;
 167   return plist;
 168 }
 169
 170 /* Make the parent of D be whatever the parent of S is, regardless
 171    of the type.  This is used when balancing an interval tree.  */
 172
 173 LISP_INLINE void
 174 interval_copy_parent (INTERVAL d, INTERVAL s)
 175 {
 176   d->up = s->up;
 177   d->up_obj = s->up_obj;
 178 }
 179
 180 /* Get the parent interval, if any, otherwise a null pointer.  Useful
 181    for walking up to the root in a "for" loop; use this to get the
 182    "next" value, and test the result to see if it's NULL.  */
 183 #define INTERVAL_PARENT_OR_NULL(i) \
 184    (INTERVAL_HAS_PARENT (i) ? INTERVAL_PARENT (i) : 0)
 185
 186 /* Reset this interval to its vanilla, or no-property state.  */
 187 #define RESET_INTERVAL(i)                     \
 188 {                                             \
 189   (i)->total_length = (i)->position = 0;      \
 190   (i)->left = (i)->right = NULL;              \
 191   interval_set_parent (i, NULL);              \
 192   (i)->write_protect = 0;                     \
 193   (i)->visible = 0;                           \
 194   (i)->front_sticky = (i)->rear_sticky = 0;   \
 195   interval_set_plist (i, Qnil);               \
 196 }
 197
 198 /* Copy the cached property values of interval FROM to interval TO.  */
 199 #define COPY_INTERVAL_CACHE(from,to)            \
 200 {                                               \
 201   (to)->write_protect = (from)->write_protect;  \
 202   (to)->visible = (from)->visible;              \
 203   (to)->front_sticky = (from)->front_sticky;    \
 204   (to)->rear_sticky = (from)->rear_sticky;      \
 205 }
 206
 207 /* Copy only the set bits of FROM's cache.  */
 208 #define MERGE_INTERVAL_CACHE(from,to)                 \
 209 {                                                     \
 210   if ((from)->write_protect) (to)->write_protect = 1; \
 211   if ((from)->visible) (to)->visible = 1;             \
 212   if ((from)->front_sticky) (to)->front_sticky = 1;   \
 213   if ((from)->rear_sticky) (to)->rear_sticky = 1;     \
 214 }
 215
 216 /* Macro determining whether the properties of an interval being
 217    inserted should be merged with the properties of the text where
 218    they are being inserted.  */
 219 #define MERGE_INSERTIONS(i) 1
 220
 221 /* Macro determining if an invisible interval should be displayed
 222    as a special glyph, or not at all.  */
 223 #define DISPLAY_INVISIBLE_GLYPH(i) 0
 224
 225 /* Is this interval visible?  Replace later with cache access.  */
 226 #define INTERVAL_VISIBLE_P(i) \
 227   (i && NILP (textget ((i)->plist, Qinvisible)))
 228
 229 /* Is this interval writable?  Replace later with cache access.  */
 230 #define INTERVAL_WRITABLE_P(i)                                  \
 231   (i && (NILP (textget ((i)->plist, Qread_only))                \
 232          || ((CONSP (Vinhibit_read_only)                        \
 233               ? !NILP (Fmemq (textget ((i)->plist, Qread_only), \
 234                               Vinhibit_read_only))              \
 235               : !NILP (Vinhibit_read_only)))))                  \
 236
 237 /* Macros to tell whether insertions before or after this interval
 238    should stick to it.  Now we have Vtext_property_default_nonsticky,
 239    so these macros are unreliable now and never used.  */
 240
 241 #if 0
 242 #define FRONT_STICKY_P(i)                               \
 243   (i && ! NILP (textget ((i)->plist, Qfront_sticky)))
 244 #define END_NONSTICKY_P(i)                              \
 245   (i && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 246 #define FRONT_NONSTICKY_P(i)                            \
 247   (i && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 248 #endif
 249
 250 /* If PROP is the `invisible' property of a character,
 251    this is 1 if the character should be treated as invisible,
 252    and 2 if it is invisible but with an ellipsis.  */
 253
 254 #define TEXT_PROP_MEANS_INVISIBLE(prop)                                 \
 255   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 256    ? !NILP (prop)                                                       \
 257    : invisible_p (prop, BVAR (current_buffer, invisibility_spec)))
 258
 259 /* Declared in alloc.c.  */
 260
 261 extern INTERVAL make_interval (void);
 262
 263 /* Declared in intervals.c.  */
 264
 265 extern INTERVAL create_root_interval (Lisp_Object);
 266 extern void copy_properties (INTERVAL, INTERVAL);
 267 extern int intervals_equal (INTERVAL, INTERVAL);
 268 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 269                                 void (*) (INTERVAL, Lisp_Object),
 270                                 Lisp_Object);
 271 extern void traverse_intervals_noorder (INTERVAL,
 272                                         void (*) (INTERVAL, Lisp_Object),
 273                                         Lisp_Object);
 274 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 275 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 276 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 277 extern INTERVAL next_interval (INTERVAL);
 278 extern INTERVAL previous_interval (INTERVAL);
 279 extern INTERVAL merge_interval_left (INTERVAL);
 280 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 281 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 282                                          struct buffer *, int);
 283 extern void verify_interval_modification (struct buffer *,
 284                                           ptrdiff_t, ptrdiff_t);
 285 extern INTERVAL balance_intervals (INTERVAL);
 286 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 287                                              ptrdiff_t, ptrdiff_t);
 288 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 289 extern int compare_string_intervals (Lisp_Object, Lisp_Object);
 290 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 291 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, int);
 292 extern void move_if_not_intangible (ptrdiff_t);
 293 extern int get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 294                                    ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 295 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 296 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 297 extern void set_intervals_multibyte (int);
 298 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 299                                          Lisp_Object *, int);
 300 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 301
 302 /* Defined in xdisp.c.  */
 303 extern int invisible_p (Lisp_Object, Lisp_Object);
 304
 305 /* Declared in textprop.c.  */
 306
 307 /* Types of hooks.  */
 308 extern Lisp_Object Qpoint_left;
 309 extern Lisp_Object Qpoint_entered;
 310 extern Lisp_Object Qmodification_hooks;
 311 extern Lisp_Object Qcategory;
 312 extern Lisp_Object Qlocal_map;
 313 extern Lisp_Object Qkeymap;
 314
 315 /* Visual properties text (including strings) may have.  */
 316 extern Lisp_Object Qfont;
 317 extern Lisp_Object Qinvisible, Qintangible;
 318
 319 /* Sticky properties.  */
 320 extern Lisp_Object Qfront_sticky, Qrear_nonsticky;
 321
 322 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 323                                          Lisp_Object, Lisp_Object,
 324                                          Lisp_Object, Lisp_Object);
 325 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 326                                         Lisp_Object, Lisp_Object,
 327                                         Lisp_Object);
 328 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 329                                    Lisp_Object, Lisp_Object, INTERVAL);
 330
 331 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 332                                 Lisp_Object);
 333 int add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 334 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 335 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 336                                            Lisp_Object, Lisp_Object*);
 337 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 338                                      Lisp_Object buffer);
 339 extern Lisp_Object get_pos_property (Lisp_Object pos, Lisp_Object prop,
 340                                      Lisp_Object object);
 341
 342 extern void syms_of_textprop (void);
 343
 344 #include "composite.h"
 345
 346 INLINE_HEADER_END