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          || !NILP (textget ((i)->plist, Qinhibit_read_only))    \
 201          || ((CONSP (Vinhibit_read_only)                        \
 202               ? !NILP (Fmemq (textget ((i)->plist, Qread_only), \
 203                               Vinhibit_read_only))              \
 204               : !NILP (Vinhibit_read_only)))))                  \
 205
 206 /* Macros to tell whether insertions before or after this interval
 207    should stick to it.  Now we have Vtext_property_default_nonsticky,
 208    so these macros are unreliable now and never used.  */
 209
 210 #if false
 211 #define FRONT_STICKY_P(i)                               \
 212   (i && ! NILP (textget ((i)->plist, Qfront_sticky)))
 213 #define END_NONSTICKY_P(i)                              \
 214   (i && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 215 #define FRONT_NONSTICKY_P(i)                            \
 216   (i && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 217 #endif
 218
 219 /* If PROP is the `invisible' property of a character,
 220    this is 1 if the character should be treated as invisible,
 221    and 2 if it is invisible but with an ellipsis.  */
 222
 223 #define TEXT_PROP_MEANS_INVISIBLE(prop)                                 \
 224   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 225    ? !NILP (prop)                                                       \
 226    : invisible_prop (prop, BVAR (current_buffer, invisibility_spec)))
 227
 228 /* Declared in alloc.c.  */
 229
 230 extern INTERVAL make_interval (void);
 231
 232 /* Declared in intervals.c.  */
 233
 234 extern INTERVAL create_root_interval (Lisp_Object);
 235 extern void copy_properties (INTERVAL, INTERVAL);
 236 extern bool intervals_equal (INTERVAL, INTERVAL);
 237 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 238                                 void (*) (INTERVAL, Lisp_Object),
 239                                 Lisp_Object);
 240 extern void traverse_intervals_noorder (INTERVAL,
 241                                         void (*) (INTERVAL, Lisp_Object),
 242                                         Lisp_Object);
 243 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 244 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 245 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 246 extern INTERVAL next_interval (INTERVAL);
 247 extern INTERVAL previous_interval (INTERVAL);
 248 extern INTERVAL merge_interval_left (INTERVAL);
 249 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 250 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 251                                          struct buffer *, bool);
 252 extern void verify_interval_modification (struct buffer *,
 253                                           ptrdiff_t, ptrdiff_t);
 254 extern INTERVAL balance_intervals (INTERVAL);
 255 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 256                                              ptrdiff_t, ptrdiff_t);
 257 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 258 extern bool compare_string_intervals (Lisp_Object, Lisp_Object);
 259 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 260 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, bool);
 261 extern void move_if_not_intangible (ptrdiff_t);
 262 extern bool get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 263                                     ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 264 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 265 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 266 extern void set_intervals_multibyte (bool);
 267 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 268                                          Lisp_Object *, bool);
 269 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 270
 271 /* Defined in xdisp.c.  */
 272 extern int invisible_prop (Lisp_Object, Lisp_Object);
 273
 274 /* Defined in textprop.c.  */
 275 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 276                                          Lisp_Object, Lisp_Object,
 277                                          Lisp_Object, Lisp_Object);
 278 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 279                                         Lisp_Object, Lisp_Object,
 280                                         Lisp_Object);
 281 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 282                                    Lisp_Object, Lisp_Object, INTERVAL);
 283
 284 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 285                                 Lisp_Object);
 286 void add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 287 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 288 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 289                                            Lisp_Object, Lisp_Object*);
 290 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 291                                      Lisp_Object buffer);
 292
 293 extern void syms_of_textprop (void);
 294
 295 #include "composite.h"
 296
 297 INLINE_HEADER_END