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