src/intervals.h

   1 /* Definitions and global variables for intervals.
   2    Copyright (C) 1993-1994, 2000-2017 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 (at
   9 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 #ifndef EMACS_INTERVALS_H
  20 #define EMACS_INTERVALS_H
  21
  22 INLINE_HEADER_BEGIN
  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   bool_bf up_obj : 1;
  47
  48   bool_bf 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   bool_bf write_protect : 1;        /* True means can't modify.  */
  55   bool_bf visible : 1;              /* False means don't display.  */
  56   bool_bf front_sticky : 1;         /* True means text inserted just
  57                                        before this interval goes into it.  */
  58   bool_bf 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 /* True if this interval has no right child.  */
  65 #define NULL_RIGHT_CHILD(i) ((i)->right == NULL)
  66
  67 /* True if this interval has no left child.  */
  68 #define NULL_LEFT_CHILD(i) ((i)->left == NULL)
  69
  70 /* True if this interval has no parent.  */
  71 #define NULL_PARENT(i) ((i)->up_obj || (i)->up.interval == 0)
  72
  73 /* True if this interval is the left child of some other interval.  */
  74 #define AM_LEFT_CHILD(i)                                        \
  75   (! NULL_PARENT (i) && INTERVAL_PARENT (i)->left == (i))
  76
  77 /* True if this interval is the right child of some other interval.  */
  78 #define AM_RIGHT_CHILD(i)                                       \
  79   (! NULL_PARENT (i) && INTERVAL_PARENT (i)->right == (i))
  80
  81 /* True if this interval has no children.  */
  82 #define LEAF_INTERVAL_P(i) ((i)->left == NULL && (i)->right == NULL)
  83
  84 /* True if this interval has no parent and is therefore the root.  */
  85 #define ROOT_INTERVAL_P(i) (NULL_PARENT (i))
  86
  87 /* True if this interval is the only interval in the interval tree.  */
  88 #define ONLY_INTERVAL_P(i) (ROOT_INTERVAL_P ((i)) && LEAF_INTERVAL_P ((i)))
  89
  90 /* True if this interval has both left and right children.  */
  91 #define BOTH_KIDS_P(i) ((i)->left != NULL && (i)->right != NULL)
  92
  93 /* The total size of all text represented by this interval and all its
  94    children in the tree.   This is zero if the interval is null.  */
  95 #define TOTAL_LENGTH(i) ((i) == NULL ? 0 : (i)->total_length)
  96
  97 /* The size of text represented by this interval alone.  */
  98 #define LENGTH(i) ((i) == NULL ? 0 : (TOTAL_LENGTH ((i))                \
  99                                       - TOTAL_LENGTH ((i)->right)       \
 100                                       - TOTAL_LENGTH ((i)->left)))
 101
 102 /* The position of the character just past the end of I.  Note that
 103    the position cache i->position must be valid for this to work.  */
 104 #define INTERVAL_LAST_POS(i) ((i)->position + LENGTH ((i)))
 105
 106 /* The total size of the left subtree of this interval.  */
 107 #define LEFT_TOTAL_LENGTH(i) ((i)->left ? (i)->left->total_length : 0)
 108
 109 /* The total size of the right subtree of this interval.  */
 110 #define RIGHT_TOTAL_LENGTH(i) ((i)->right ? (i)->right->total_length : 0)
 111
 112 /* These macros are for dealing with the interval properties.  */
 113
 114 /* True if this is a default interval, which is the same as being null
 115    or having no properties.  */
 116 #define DEFAULT_INTERVAL_P(i) (!i || EQ ((i)->plist, Qnil))
 117
 118 /* Test what type of parent we have.  Three possibilities: another
 119    interval, a buffer or string object, or NULL.  */
 120 #define INTERVAL_HAS_PARENT(i) (! (i)->up_obj && (i)->up.interval != 0)
 121 #define INTERVAL_HAS_OBJECT(i) ((i)->up_obj)
 122
 123 /* Use these macros to get parent of an interval.
 124
 125    The choice of macros is dependent on the type needed.  Don't add
 126    casts to get around this, it will break some development work in
 127    progress.  */
 128
 129 #define INTERVAL_PARENT(i)                                      \
 130    (eassert ((i) != 0 && ! (i)->up_obj), (i)->up.interval)
 131
 132 #define GET_INTERVAL_OBJECT(d,s) (eassert ((s)->up_obj), (d) = (s)->up.obj)
 133
 134 /* Use these functions to set Lisp_Object
 135    or pointer slots of struct interval.  */
 136
 137 INLINE void
 138 set_interval_object (INTERVAL i, Lisp_Object obj)
 139 {
 140   eassert (BUFFERP (obj) || STRINGP (obj));
 141   i->up_obj = 1;
 142   i->up.obj = obj;
 143 }
 144
 145 INLINE void
 146 set_interval_parent (INTERVAL i, INTERVAL parent)
 147 {
 148   i->up_obj = false;
 149   i->up.interval = parent;
 150 }
 151
 152 INLINE void
 153 set_interval_plist (INTERVAL i, Lisp_Object plist)
 154 {
 155   i->plist = plist;
 156 }
 157
 158 /* Get the parent interval, if any, otherwise a null pointer.  Useful
 159    for walking up to the root in a "for" loop; use this to get the
 160    "next" value, and test the result to see if it's NULL.  */
 161 #define INTERVAL_PARENT_OR_NULL(i) \
 162    (INTERVAL_HAS_PARENT (i) ? INTERVAL_PARENT (i) : 0)
 163
 164 /* Reset this interval to its vanilla, or no-property state.  */
 165 #define RESET_INTERVAL(i)                     \
 166  do {                                         \
 167   (i)->total_length = (i)->position = 0;      \
 168   (i)->left = (i)->right = NULL;              \
 169   set_interval_parent (i, NULL);              \
 170   (i)->write_protect = false;                 \
 171   (i)->visible = false;                       \
 172   (i)->front_sticky = (i)->rear_sticky = false; \
 173   set_interval_plist (i, Qnil);               \
 174  } while (false)
 175
 176 /* Copy the cached property values of interval FROM to interval TO.  */
 177 #define COPY_INTERVAL_CACHE(from,to)            \
 178  do {                                           \
 179   (to)->write_protect = (from)->write_protect;  \
 180   (to)->visible = (from)->visible;              \
 181   (to)->front_sticky = (from)->front_sticky;    \
 182   (to)->rear_sticky = (from)->rear_sticky;      \
 183  } while (false)
 184
 185 /* Copy only the set bits of FROM's cache.  */
 186 #define MERGE_INTERVAL_CACHE(from,to)                           \
 187  do {                                                           \
 188   if ((from)->write_protect) (to)->write_protect = true;        \
 189   if ((from)->visible) (to)->visible = true;                    \
 190   if ((from)->front_sticky) (to)->front_sticky = true;          \
 191   if ((from)->rear_sticky) (to)->rear_sticky = true;            \
 192  } while (false)
 193
 194 /* Is this interval visible?  Replace later with cache access.  */
 195 #define INTERVAL_VISIBLE_P(i) \
 196   (i && NILP (textget ((i)->plist, Qinvisible)))
 197
 198 /* Is this interval writable?  Replace later with cache access.  */
 199 #define INTERVAL_WRITABLE_P(i)                                  \
 200   (i && (NILP (textget ((i)->plist, Qread_only))                \
 201          || !NILP (textget ((i)->plist, Qinhibit_read_only))    \
 202          || ((CONSP (Vinhibit_read_only)                        \
 203               ? !NILP (Fmemq (textget ((i)->plist, Qread_only), \
 204                               Vinhibit_read_only))              \
 205               : !NILP (Vinhibit_read_only)))))                  \
 206
 207 /* Macros to tell whether insertions before or after this interval
 208    should stick to it.  Now we have Vtext_property_default_nonsticky,
 209    so these macros are unreliable now and never used.  */
 210
 211 #if false
 212 #define FRONT_STICKY_P(i)                               \
 213   (i && ! NILP (textget ((i)->plist, Qfront_sticky)))
 214 #define END_NONSTICKY_P(i)                              \
 215   (i && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 216 #define FRONT_NONSTICKY_P(i)                            \
 217   (i && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 218 #endif
 219
 220 /* If PROP is the `invisible' property of a character,
 221    this is 1 if the character should be treated as invisible,
 222    and 2 if it is invisible but with an ellipsis.  */
 223
 224 #define TEXT_PROP_MEANS_INVISIBLE(prop)                                 \
 225   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 226    ? !NILP (prop)                                                       \
 227    : invisible_prop (prop, BVAR (current_buffer, invisibility_spec)))
 228
 229 /* Declared in alloc.c.  */
 230
 231 extern INTERVAL make_interval (void);
 232
 233 /* Declared in intervals.c.  */
 234
 235 extern INTERVAL create_root_interval (Lisp_Object);
 236 extern void copy_properties (INTERVAL, INTERVAL);
 237 extern bool intervals_equal (INTERVAL, INTERVAL);
 238 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 239                                 void (*) (INTERVAL, Lisp_Object),
 240                                 Lisp_Object);
 241 extern void traverse_intervals_noorder (INTERVAL,
 242                                         void (*) (INTERVAL, Lisp_Object),
 243                                         Lisp_Object);
 244 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 245 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 246 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 247 extern INTERVAL next_interval (INTERVAL);
 248 extern INTERVAL previous_interval (INTERVAL);
 249 extern INTERVAL merge_interval_left (INTERVAL);
 250 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 251 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 252                                          struct buffer *, bool);
 253 extern void verify_interval_modification (struct buffer *,
 254                                           ptrdiff_t, ptrdiff_t);
 255 extern INTERVAL balance_intervals (INTERVAL);
 256 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 257                                              ptrdiff_t, ptrdiff_t);
 258 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 259 extern bool compare_string_intervals (Lisp_Object, Lisp_Object);
 260 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 261 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, bool);
 262 extern void move_if_not_intangible (ptrdiff_t);
 263 extern bool get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 264                                     ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 265 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 266 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 267 extern void set_intervals_multibyte (bool);
 268 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 269                                          Lisp_Object *, bool);
 270 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 271
 272 /* Defined in xdisp.c.  */
 273 extern int invisible_prop (Lisp_Object, Lisp_Object);
 274
 275 /* Defined in textprop.c.  */
 276 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 277                                          Lisp_Object, Lisp_Object,
 278                                          Lisp_Object, Lisp_Object);
 279 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 280                                         Lisp_Object, Lisp_Object,
 281                                         Lisp_Object);
 282 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 283                                    Lisp_Object, Lisp_Object, INTERVAL);
 284
 285 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 286                                 Lisp_Object);
 287 void add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 288 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 289 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 290                                            Lisp_Object, Lisp_Object*);
 291 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 292                                      Lisp_Object buffer);
 293
 294 extern void syms_of_textprop (void);
 295
 296 INLINE_HEADER_END
 297
 298 #endif /* EMACS_INTERVALS_H */