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
  60   /* Properties of this interval.
  61      The mark bit on this field says whether this particular interval
  62      tree node has been visited.  Since intervals should never be
  63      shared, GC aborts if it seems to have visited an interval twice.  */
  64   Lisp_Object plist;
  65 };
  66
  67 /* These are macros for dealing with the interval tree.  */
  68
  69 /* Size of the structure used to represent an interval.  */
  70 #define INTERVAL_SIZE (sizeof (struct interval))
  71
  72 /* Size of a pointer to an interval structure.  */
  73 #define INTERVAL_PTR_SIZE (sizeof (struct interval *))
  74
  75 #define NULL_INTERVAL_P(i) ((i) == NULL_INTERVAL)
  76
  77 /* True if this interval has no right child.  */
  78 #define NULL_RIGHT_CHILD(i) ((i)->right == NULL_INTERVAL)
  79
  80 /* True if this interval has no left child.  */
  81 #define NULL_LEFT_CHILD(i) ((i)->left == NULL_INTERVAL)
  82
  83 /* True if this interval has no parent.  */
  84 #define NULL_PARENT(i) ((i)->up_obj || (i)->up.interval == 0)
  85
  86 /* True if this interval is the left child of some other interval.  */
  87 #define AM_LEFT_CHILD(i) (! NULL_PARENT (i) \
  88                           && INTERVAL_PARENT (i)->left == (i))
  89
  90 /* True if this interval is the right child of some other interval.  */
  91 #define AM_RIGHT_CHILD(i) (! NULL_PARENT (i) \
  92                            && INTERVAL_PARENT (i)->right == (i))
  93
  94 /* True if this interval has no children.  */
  95 #define LEAF_INTERVAL_P(i) ((i)->left == NULL_INTERVAL \
  96                             && (i)->right == NULL_INTERVAL)
  97
  98 /* True if this interval has no parent and is therefore the root.  */
  99 #define ROOT_INTERVAL_P(i) (NULL_PARENT (i))
 100
 101 /* True if this interval is the only interval in the interval tree.  */
 102 #define ONLY_INTERVAL_P(i) (ROOT_INTERVAL_P ((i)) && LEAF_INTERVAL_P ((i)))
 103
 104 /* True if this interval has both left and right children.  */
 105 #define BOTH_KIDS_P(i) ((i)->left != NULL_INTERVAL     \
 106                         && (i)->right != NULL_INTERVAL)
 107
 108 /* The total size of all text represented by this interval and all its
 109    children in the tree.   This is zero if the interval is null.  */
 110 #define TOTAL_LENGTH(i) ((i) == NULL_INTERVAL ? 0 : (i)->total_length)
 111
 112 /* The size of text represented by this interval alone.  */
 113 #define LENGTH(i) ((i) == NULL_INTERVAL ? 0 : (TOTAL_LENGTH ((i))          \
 114                                                - TOTAL_LENGTH ((i)->right) \
 115                                                - TOTAL_LENGTH ((i)->left)))
 116
 117 /* The position of the character just past the end of I.  Note that
 118    the position cache i->position must be valid for this to work.  */
 119 #define INTERVAL_LAST_POS(i) ((i)->position + LENGTH ((i)))
 120
 121 /* The total size of the left subtree of this interval.  */
 122 #define LEFT_TOTAL_LENGTH(i) ((i)->left ? (i)->left->total_length : 0)
 123
 124 /* The total size of the right subtree of this interval.  */
 125 #define RIGHT_TOTAL_LENGTH(i) ((i)->right ? (i)->right->total_length : 0)
 126
 127
 128 /* These macros are for dealing with the interval properties.  */
 129
 130 /* True if this is a default interval, which is the same as being null
 131    or having no properties.  */
 132 #define DEFAULT_INTERVAL_P(i) (NULL_INTERVAL_P (i) || EQ ((i)->plist, Qnil))
 133
 134 /* Test what type of parent we have.  Three possibilities: another
 135    interval, a buffer or string object, or NULL_INTERVAL.  */
 136 #define INTERVAL_HAS_PARENT(i) ((i)->up_obj == 0 && (i)->up.interval != 0)
 137 #define INTERVAL_HAS_OBJECT(i) ((i)->up_obj)
 138
 139 /* Set/get parent of an interval.
 140
 141    The choice of macros is dependent on the type needed.  Don't add
 142    casts to get around this, it will break some development work in
 143    progress.  */
 144 #define SET_INTERVAL_PARENT(i,p) \
 145    ((i)->up_obj = 0, (i)->up.interval = (p))
 146 #define SET_INTERVAL_OBJECT(i,o) \
 147    (eassert (BUFFERP (o) || STRINGP (o)), (i)->up_obj = 1, (i)->up.obj = (o))
 148 #define INTERVAL_PARENT(i) \
 149    (eassert ((i) != 0 && (i)->up_obj == 0),(i)->up.interval)
 150 #define GET_INTERVAL_OBJECT(d,s) (eassert((s)->up_obj == 1), (d) = (s)->up.obj)
 151
 152 /* Make the parent of D be whatever the parent of S is, regardless of
 153    type.  This is used when balancing an interval tree.  */
 154 #define COPY_INTERVAL_PARENT(d,s) \
 155    ((d)->up = (s)->up, (d)->up_obj = (s)->up_obj)
 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_INTERVAL.  */
 160 #define INTERVAL_PARENT_OR_NULL(i) \
 161    (INTERVAL_HAS_PARENT (i) ? INTERVAL_PARENT (i) : 0)
 162
 163 /* Abort if interval I's size is negative.  */
 164 #define CHECK_TOTAL_LENGTH(i)                \
 165   do                                         \
 166     {                                        \
 167       if ((i)->total_length < 0)             \
 168         abort ();                            \
 169     }                                        \
 170   while (0)
 171
 172 /* Reset this interval to its vanilla, or no-property state.  */
 173 #define RESET_INTERVAL(i) \
 174 { \
 175     (i)->total_length = (i)->position = 0;    \
 176     (i)->left = (i)->right = NULL_INTERVAL;   \
 177     SET_INTERVAL_PARENT (i, NULL_INTERVAL);   \
 178     (i)->write_protect = 0;                   \
 179     (i)->visible = 0;                         \
 180     (i)->front_sticky = (i)->rear_sticky = 0; \
 181     (i)->plist = Qnil;                        \
 182 }
 183
 184 /* Copy the cached property values of interval FROM to interval TO.  */
 185 #define COPY_INTERVAL_CACHE(from,to) \
 186 { \
 187   (to)->write_protect = (from)->write_protect; \
 188   (to)->visible = (from)->visible;             \
 189   (to)->front_sticky = (from)->front_sticky;   \
 190   (to)->rear_sticky = (from)->rear_sticky;     \
 191 }
 192
 193 /* Copy only the set bits of FROM's cache.  */
 194 #define MERGE_INTERVAL_CACHE(from,to) \
 195 { \
 196   if ((from)->write_protect) (to)->write_protect = 1; \
 197   if ((from)->visible) (to)->visible = 1;             \
 198   if ((from)->front_sticky) (to)->front_sticky = 1;   \
 199   if ((from)->rear_sticky) (to)->rear_sticky = 1;     \
 200 }
 201
 202 /* Macro determining whether the properties of an interval being
 203    inserted should be merged with the properties of the text where
 204    they are being inserted.  */
 205 #define MERGE_INSERTIONS(i) 1
 206
 207 /* Macro determining if an invisible interval should be displayed
 208    as a special glyph, or not at all.  */
 209 #define DISPLAY_INVISIBLE_GLYPH(i) 0
 210
 211 /* Is this interval visible?  Replace later with cache access.  */
 212 #define INTERVAL_VISIBLE_P(i) \
 213   (! NULL_INTERVAL_P (i) && NILP (textget ((i)->plist, Qinvisible)))
 214
 215 /* Is this interval writable?  Replace later with cache access.  */
 216 #define INTERVAL_WRITABLE_P(i)                                  \
 217   (! NULL_INTERVAL_P (i)                                        \
 218    && (NILP (textget ((i)->plist, Qread_only))                  \
 219        || ((CONSP (Vinhibit_read_only)                          \
 220             ? !NILP (Fmemq (textget ((i)->plist, Qread_only),   \
 221                             Vinhibit_read_only))                \
 222             : !NILP (Vinhibit_read_only)))))                    \
 223
 224 /* Macros to tell whether insertions before or after this interval
 225    should stick to it.  */
 226 /* Replace later with cache access */
 227 /*#define FRONT_STICKY_P(i) ((i)->front_sticky != 0)
 228   #define END_STICKY_P(i) ((i)->rear_sticky != 0)*/
 229 /* As we now have Vtext_property_default_nonsticky, these macros are
 230    unreliable now.  Currently, they are never used.  */
 231 #define FRONT_STICKY_P(i) \
 232   (! NULL_INTERVAL_P (i) && ! NILP (textget ((i)->plist, Qfront_sticky)))
 233 #define END_NONSTICKY_P(i) \
 234   (! NULL_INTERVAL_P (i) && ! NILP (textget ((i)->plist, Qrear_nonsticky)))
 235 #define FRONT_NONSTICKY_P(i) \
 236   (! NULL_INTERVAL_P (i) && ! EQ (Qt, textget ((i)->plist, Qfront_sticky)))
 237
 238
 239 /* If PROP is the `invisible' property of a character,
 240    this is 1 if the character should be treated as invisible,
 241    and 2 if it is invisible but with an ellipsis.  */
 242
 243 #define TEXT_PROP_MEANS_INVISIBLE(prop)                         \
 244   (EQ (BVAR (current_buffer, invisibility_spec), Qt)                    \
 245    ? !NILP (prop)                                               \
 246    : invisible_p (prop, BVAR (current_buffer, invisibility_spec)))
 247
 248 /* Declared in alloc.c.  */
 249
 250 extern INTERVAL make_interval (void);
 251
 252 /* Declared in intervals.c.  */
 253
 254 extern INTERVAL create_root_interval (Lisp_Object);
 255 extern void copy_properties (INTERVAL, INTERVAL);
 256 extern int intervals_equal (INTERVAL, INTERVAL);
 257 extern void traverse_intervals (INTERVAL, ptrdiff_t,
 258                                 void (*) (INTERVAL, Lisp_Object),
 259                                 Lisp_Object);
 260 extern void traverse_intervals_noorder (INTERVAL,
 261                                         void (*) (INTERVAL, Lisp_Object),
 262                                         Lisp_Object);
 263 extern INTERVAL split_interval_right (INTERVAL, ptrdiff_t);
 264 extern INTERVAL split_interval_left (INTERVAL, ptrdiff_t);
 265 extern INTERVAL find_interval (INTERVAL, ptrdiff_t);
 266 extern INTERVAL next_interval (INTERVAL);
 267 extern INTERVAL previous_interval (INTERVAL);
 268 extern INTERVAL merge_interval_left (INTERVAL);
 269 extern void offset_intervals (struct buffer *, ptrdiff_t, ptrdiff_t);
 270 extern void graft_intervals_into_buffer (INTERVAL, ptrdiff_t, ptrdiff_t,
 271                                          struct buffer *, int);
 272 extern void verify_interval_modification (struct buffer *,
 273                                           ptrdiff_t, ptrdiff_t);
 274 extern INTERVAL balance_intervals (INTERVAL);
 275 extern void copy_intervals_to_string (Lisp_Object, struct buffer *,
 276                                              ptrdiff_t, ptrdiff_t);
 277 extern INTERVAL copy_intervals (INTERVAL, ptrdiff_t, ptrdiff_t);
 278 extern int compare_string_intervals (Lisp_Object, Lisp_Object);
 279 extern Lisp_Object textget (Lisp_Object, Lisp_Object);
 280 extern Lisp_Object lookup_char_property (Lisp_Object, Lisp_Object, int);
 281 extern void move_if_not_intangible (ptrdiff_t);
 282 extern int get_property_and_range (ptrdiff_t, Lisp_Object, Lisp_Object *,
 283                                    ptrdiff_t *, ptrdiff_t *, Lisp_Object);
 284 extern Lisp_Object get_local_map (ptrdiff_t, struct buffer *, Lisp_Object);
 285 extern INTERVAL update_interval (INTERVAL, ptrdiff_t);
 286 extern void set_intervals_multibyte (int);
 287 extern INTERVAL validate_interval_range (Lisp_Object, Lisp_Object *,
 288                                          Lisp_Object *, int);
 289 extern INTERVAL interval_of (ptrdiff_t, Lisp_Object);
 290
 291 /* Defined in xdisp.c.  */
 292 extern int invisible_p (Lisp_Object, Lisp_Object);
 293
 294 /* Declared in textprop.c.  */
 295
 296 /* Types of hooks.  */
 297 extern Lisp_Object Qpoint_left;
 298 extern Lisp_Object Qpoint_entered;
 299 extern Lisp_Object Qmodification_hooks;
 300 extern Lisp_Object Qcategory;
 301 extern Lisp_Object Qlocal_map;
 302 extern Lisp_Object Qkeymap;
 303
 304 /* Visual properties text (including strings) may have.  */
 305 extern Lisp_Object Qfont;
 306 extern Lisp_Object Qinvisible, Qintangible;
 307
 308 /* Sticky properties.  */
 309 extern Lisp_Object Qfront_sticky, Qrear_nonsticky;
 310
 311 EXFUN (Fget_char_property, 3);
 312 EXFUN (Fget_text_property, 3);
 313 EXFUN (Ftext_properties_at, 2);
 314 EXFUN (Fnext_property_change, 3);
 315 EXFUN (Fadd_text_properties, 4);
 316 EXFUN (Fset_text_properties, 4);
 317 EXFUN (Fremove_text_properties, 4);
 318 EXFUN (Fremove_list_of_text_properties, 4);
 319 EXFUN (Ftext_property_any, 5);
 320 EXFUN (Fprevious_single_char_property_change, 4);
 321 extern Lisp_Object copy_text_properties (Lisp_Object, Lisp_Object,
 322                                          Lisp_Object, Lisp_Object,
 323                                          Lisp_Object, Lisp_Object);
 324 extern Lisp_Object set_text_properties (Lisp_Object, Lisp_Object,
 325                                         Lisp_Object, Lisp_Object,
 326                                         Lisp_Object);
 327 extern void set_text_properties_1 (Lisp_Object, Lisp_Object,
 328                                    Lisp_Object, Lisp_Object, INTERVAL);
 329
 330 Lisp_Object text_property_list (Lisp_Object, Lisp_Object, Lisp_Object,
 331                                 Lisp_Object);
 332 int add_text_properties_from_list (Lisp_Object, Lisp_Object, Lisp_Object);
 333 Lisp_Object extend_property_ranges (Lisp_Object, Lisp_Object);
 334 Lisp_Object get_char_property_and_overlay (Lisp_Object, Lisp_Object,
 335                                            Lisp_Object, Lisp_Object*);
 336 extern int text_property_stickiness (Lisp_Object prop, Lisp_Object pos,
 337                                      Lisp_Object buffer);
 338 extern Lisp_Object get_pos_property (Lisp_Object pos, Lisp_Object prop,
 339                                      Lisp_Object object);
 340
 341 extern void syms_of_textprop (void);
 342
 343 #include "composite.h"