src/intervals.h

   1 /* Definitions and global variables for intervals.
   2    Copyright (C) 1993-1994, 2000-2013 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 INLINE void
 137 set_interval_parent (INTERVAL i, INTERVAL parent)
 138 {
 139   i->up_obj = 0;
 140   i->up.interval = parent;
 141 }
 142
 143 INLINE void
 144 set_interval_plist (INTERVAL i, Lisp_Object plist)
 145 {
 146   i->plist = plist;
 147 }
 148
 149 /* Get the parent interval, if any, otherwise a null pointer.  Useful
 150    for walking up to the root in a "for" loop; use this to get the
 151    "next" value, and test the result to see if it's NULL.  */
 152 #define INTERVAL_PARENT_OR_NULL(i) \
 153    (INTERVAL_HAS_PARENT (i) ? INTERVAL_PARENT (i) : 0)
 154
 155 /* Reset this interval to its vanilla, or no-property state.  */
 156 #define RESET_INTERVAL(i)                     \
 157 {                                             \
 158   (i)->total_length = (i)->position = 0;      \
 159   (i)->left = (i)->right = NULL;              \
 160   set_interval_parent (i, NULL);              \
 161   (i)->write_protect = 0;                     \
 162   (i)->visible = 0;                           \
 163   (i)->front_sticky = (i)->rear_sticky = 0;   \
 164   set_interval_plist (i, Qnil);               \
 165 }
 166
 167 /* Copy the cached property values of interval FROM to interval TO.  */
 168 #define COPY_INTERVAL_CACHE(from,to)            \
 169 {                                               \
 170   (to)->write_protect = (from)->write_protect;  \
 171   (to)->visible = (from)->visible;              \
 172   (to)->front_sticky = (from)->front_sticky;    \
 173   (to)->rear_sticky = (from)->rear_sticky;      \
 174 }
 175
 176 /* Copy only the set bits of FROM's cache.  */
 177 #define MERGE_INTERVAL_CACHE(from,to)                 \
 178 {                                                     \
 179   if ((from)->write_protect) (to)->write_protect = 1; \
 180   if ((from)->visible) (to)->visible = 1;             \
 181   if ((from)->front_sticky) (to)->front_sticky = 1;   \
 182   if ((from)->rear_sticky) (to)->rear_sticky = 1;     \
 183 }
 184
 185 /* Is this interval visible?  Replace later with cache access.  */
 186 #define INTERVAL_VISIBLE_P(i) \
 187   (i && NILP (textget ((i)->plist, Qinvisible)))
 188
 189 /* Is this interval writable?  Replace later with cache access.  */
 190 #define INTERVAL_WRITABLE_P(i)                                  \
 191   (i && (NILP (textget ((i)->plist, Qread_only))                \
 192          || ((CONSP (Vinhibit_read_only)                        \
 193               ? !NILP (Fmemq (textget ((i)->plist, Qread_only), \
 194                               Vinhibit_read_only))              \
 195               : !NILP (Vinhibit_read_only)))))                  \
 196
 197 /* Macros to tell whether insertions before or after this interval
 198    should stick to it.  Now we have Vtext_property_default_nonsticky,
 199    so these macros are unreliable now and never used.  */
 200
 201 #if 0
 202 #define FRONT_STICKY_P(i)                               \
 203   (i && ! NILP (textget ((i)->plist, Qfront_sticky)))
 204 #define END_NONSTICKY_P(i)                              \
 205   (i && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 206 #define FRONT_NONSTICKY_P(i)                            \
 207   (i && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 208 #endif
 209
 210 /* If PROP is the `invisible' property of a character,
 211    this is 1 if the character should be treated as invisible,
 212    and 2 if it is invisible but with an ellipsis.  */
 213
 214 #define TEXT_PROP_MEANS_INVISIBLE(prop)                                 \
 215   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 216    ? !NILP (prop)                                                       \
 217    : invisible_p (prop, BVAR (current_buffer, invisibility_spec)))
 218
 219 /* Declared in alloc.c.  */
 220
 221 extern INTERVAL make_interval (void);
 222
 223 /* Declared in intervals.c.  */
 224
 225 extern INTERVAL create_root_interval (Lisp_Object);
 226 extern void copy_properties (INTERVAL, INTERVAL);
 227 extern bool intervals_equal (INTERVAL, INTERVAL);
 228 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 229                                 void (*) (INTERVAL, Lisp_Object),
 230                                 Lisp_Object);
 231 extern void traverse_intervals_noorder (INTERVAL,
 232                                         void (*) (INTERVAL, Lisp_Object),
 233                                         Lisp_Object);
 234 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 235 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 236 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 237 extern INTERVAL next_interval (INTERVAL);
 238 extern INTERVAL previous_interval (INTERVAL);
 239 extern INTERVAL merge_interval_left (INTERVAL);
 240 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 241 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 242                                          struct buffer *, bool);
 243 extern void verify_interval_modification (struct buffer *,
 244                                           ptrdiff_t, ptrdiff_t);
 245 extern INTERVAL balance_intervals (INTERVAL);
 246 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 247                                              ptrdiff_t, ptrdiff_t);
 248 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 249 extern bool compare_string_intervals (Lisp_Object, Lisp_Object);
 250 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 251 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, bool);
 252 extern void move_if_not_intangible (ptrdiff_t);
 253 extern bool get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 254                                     ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 255 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 256 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 257 extern void set_intervals_multibyte (bool);
 258 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 259                                          Lisp_Object *, bool);
 260 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 261
 262 /* Defined in xdisp.c.  */
 263 extern int invisible_p (Lisp_Object, Lisp_Object);
 264
 265 /* Declared in textprop.c.  */
 266
 267 /* Types of hooks.  */
 268 extern Lisp_Object Qpoint_left;
 269 extern Lisp_Object Qpoint_entered;
 270 extern Lisp_Object Qmodification_hooks;
 271 extern Lisp_Object Qcategory;
 272 extern Lisp_Object Qlocal_map;
 273 extern Lisp_Object Qkeymap;
 274
 275 /* Visual properties text (including strings) may have.  */
 276 extern Lisp_Object Qfont;
 277 extern Lisp_Object Qinvisible, Qintangible;
 278
 279 /* Sticky properties.  */
 280 extern Lisp_Object Qfront_sticky, Qrear_nonsticky;
 281
 282 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 283                                          Lisp_Object, Lisp_Object,
 284                                          Lisp_Object, Lisp_Object);
 285 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 286                                         Lisp_Object, Lisp_Object,
 287                                         Lisp_Object);
 288 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 289                                    Lisp_Object, Lisp_Object, INTERVAL);
 290
 291 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 292                                 Lisp_Object);
 293 void add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 294 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 295 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 296                                            Lisp_Object, Lisp_Object*);
 297 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 298                                      Lisp_Object buffer);
 299 extern Lisp_Object get_pos_property (Lisp_Object pos, Lisp_Object prop,
 300                                      Lisp_Object object);
 301
 302 extern void syms_of_textprop (void);
 303
 304 #include "composite.h"
 305
 306 INLINE_HEADER_END