src/intervals.h

   1 /* Definitions and global variables for intervals.
   2    Copyright (C) 1993-1994, 2000-2015 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   bool_bf up_obj : 1;
  46
  47   bool_bf 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   bool_bf write_protect : 1;        /* True means can't modify.  */
  54   bool_bf visible : 1;              /* False means don't display.  */
  55   bool_bf front_sticky : 1;         /* True means text inserted just
  56                                        before this interval goes into it.  */
  57   bool_bf 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 && (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), (i)->up.interval)
 130
 131 #define GET_INTERVAL_OBJECT(d,s) (eassert ((s)->up_obj), (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_object (INTERVAL i, Lisp_Object obj)
 138 {
 139   eassert (BUFFERP (obj) || STRINGP (obj));
 140   i->up_obj = 1;
 141   i->up.obj = obj;
 142 }
 143
 144 INLINE void
 145 set_interval_parent (INTERVAL i, INTERVAL parent)
 146 {
 147   i->up_obj = false;
 148   i->up.interval = parent;
 149 }
 150
 151 INLINE void
 152 set_interval_plist (INTERVAL i, Lisp_Object plist)
 153 {
 154   i->plist = plist;
 155 }
 156
 157 /* Get the parent interval, if any, otherwise a null pointer.  Useful
 158    for walking up to the root in a "for" loop; use this to get the
 159    "next" value, and test the result to see if it's NULL.  */
 160 #define INTERVAL_PARENT_OR_NULL(i) \
 161    (INTERVAL_HAS_PARENT (i) ? INTERVAL_PARENT (i) : 0)
 162
 163 /* Reset this interval to its vanilla, or no-property state.  */
 164 #define RESET_INTERVAL(i)                     \
 165  do {                                         \
 166   (i)->total_length = (i)->position = 0;      \
 167   (i)->left = (i)->right = NULL;              \
 168   set_interval_parent (i, NULL);              \
 169   (i)->write_protect = false;                 \
 170   (i)->visible = false;                       \
 171   (i)->front_sticky = (i)->rear_sticky = false; \
 172   set_interval_plist (i, Qnil);               \
 173  } while (false)
 174
 175 /* Copy the cached property values of interval FROM to interval TO.  */
 176 #define COPY_INTERVAL_CACHE(from,to)            \
 177  do {                                           \
 178   (to)->write_protect = (from)->write_protect;  \
 179   (to)->visible = (from)->visible;              \
 180   (to)->front_sticky = (from)->front_sticky;    \
 181   (to)->rear_sticky = (from)->rear_sticky;      \
 182  } while (false)
 183
 184 /* Copy only the set bits of FROM's cache.  */
 185 #define MERGE_INTERVAL_CACHE(from,to)                           \
 186  do {                                                           \
 187   if ((from)->write_protect) (to)->write_protect = true;        \
 188   if ((from)->visible) (to)->visible = true;                    \
 189   if ((from)->front_sticky) (to)->front_sticky = true;          \
 190   if ((from)->rear_sticky) (to)->rear_sticky = true;            \
 191  } while (false)
 192
 193 /* Is this interval visible?  Replace later with cache access.  */
 194 #define INTERVAL_VISIBLE_P(i) \
 195   (i && NILP (textget ((i)->plist, Qinvisible)))
 196
 197 /* Is this interval writable?  Replace later with cache access.  */
 198 #define INTERVAL_WRITABLE_P(i)                                  \
 199   (i && (NILP (textget ((i)->plist, Qread_only))                \
 200          || ((CONSP (Vinhibit_read_only)                        \
 201               ? !NILP (Fmemq (textget ((i)->plist, Qread_only), \
 202                               Vinhibit_read_only))              \
 203               : !NILP (Vinhibit_read_only)))))                  \
 204
 205 /* Macros to tell whether insertions before or after this interval
 206    should stick to it.  Now we have Vtext_property_default_nonsticky,
 207    so these macros are unreliable now and never used.  */
 208
 209 #if false
 210 #define FRONT_STICKY_P(i)                               \
 211   (i && ! NILP (textget ((i)->plist, Qfront_sticky)))
 212 #define END_NONSTICKY_P(i)                              \
 213   (i && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 214 #define FRONT_NONSTICKY_P(i)                            \
 215   (i && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 216 #endif
 217
 218 /* If PROP is the `invisible' property of a character,
 219    this is 1 if the character should be treated as invisible,
 220    and 2 if it is invisible but with an ellipsis.  */
 221
 222 #define TEXT_PROP_MEANS_INVISIBLE(prop)                                 \
 223   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 224    ? !NILP (prop)                                                       \
 225    : invisible_p (prop, BVAR (current_buffer, invisibility_spec)))
 226
 227 /* Declared in alloc.c.  */
 228
 229 extern INTERVAL make_interval (void);
 230
 231 /* Declared in intervals.c.  */
 232
 233 extern INTERVAL create_root_interval (Lisp_Object);
 234 extern void copy_properties (INTERVAL, INTERVAL);
 235 extern bool intervals_equal (INTERVAL, INTERVAL);
 236 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 237                                 void (*) (INTERVAL, Lisp_Object),
 238                                 Lisp_Object);
 239 extern void traverse_intervals_noorder (INTERVAL,
 240                                         void (*) (INTERVAL, Lisp_Object),
 241                                         Lisp_Object);
 242 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 243 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 244 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 245 extern INTERVAL next_interval (INTERVAL);
 246 extern INTERVAL previous_interval (INTERVAL);
 247 extern INTERVAL merge_interval_left (INTERVAL);
 248 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 249 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 250                                          struct buffer *, bool);
 251 extern void verify_interval_modification (struct buffer *,
 252                                           ptrdiff_t, ptrdiff_t);
 253 extern INTERVAL balance_intervals (INTERVAL);
 254 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 255                                              ptrdiff_t, ptrdiff_t);
 256 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 257 extern bool compare_string_intervals (Lisp_Object, Lisp_Object);
 258 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 259 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, bool);
 260 extern void move_if_not_intangible (ptrdiff_t);
 261 extern bool get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 262                                     ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 263 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 264 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 265 extern void set_intervals_multibyte (bool);
 266 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 267                                          Lisp_Object *, bool);
 268 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 269
 270 /* Defined in xdisp.c.  */
 271 extern int invisible_p (Lisp_Object, Lisp_Object);
 272
 273 /* Declared in textprop.c.  */
 274
 275 /* Types of hooks.  */
 276 extern Lisp_Object Qpoint_left;
 277 extern Lisp_Object Qpoint_entered;
 278 extern Lisp_Object Qmodification_hooks;
 279 extern Lisp_Object Qcategory;
 280 extern Lisp_Object Qlocal_map;
 281 extern Lisp_Object Qkeymap;
 282
 283 /* Visual properties text (including strings) may have.  */
 284 extern Lisp_Object Qfont;
 285 extern Lisp_Object Qinvisible, Qintangible;
 286
 287 /* Sticky properties.  */
 288 extern Lisp_Object Qfront_sticky, Qrear_nonsticky;
 289
 290 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 291                                          Lisp_Object, Lisp_Object,
 292                                          Lisp_Object, Lisp_Object);
 293 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 294                                         Lisp_Object, Lisp_Object,
 295                                         Lisp_Object);
 296 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 297                                    Lisp_Object, Lisp_Object, INTERVAL);
 298
 299 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 300                                 Lisp_Object);
 301 void add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 302 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 303 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 304                                            Lisp_Object, Lisp_Object*);
 305 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 306                                      Lisp_Object buffer);
 307
 308 extern void syms_of_textprop (void);
 309
 310 #include "composite.h"
 311
 312 INLINE_HEADER_END