/*
* tkTextBTree.c (CTk) --
*
* This file contains code that manages the B-tree representation
* of text for Tk's text widget and implements character and
* toggle segment types.
*
* Copyright (c) 1992-1994 The Regents of the University of California.
* Copyright (c) 1994-1995 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* @(#) $Id: ctk.shar,v 1.50 1996/01/15 14:47:16 andrewm Exp andrewm $
*/
#include "tkInt.h"
#include "tkPort.h"
#include "tkText.h"
/*
* The data structure below keeps summary information about one tag as part
* of the tag information in a node.
*/
typedef struct Summary {
TkTextTag *tagPtr; /* Handle for tag. */
int toggleCount; /* Number of transitions into or
* out of this tag that occur in
* the subtree rooted at this node. */
struct Summary *nextPtr; /* Next in list of all tags for same
* node, or NULL if at end of list. */
} Summary;
/*
* The data structure below defines a node in the B-tree.
*/
typedef struct Node {
struct Node *parentPtr; /* Pointer to parent node, or NULL if
* this is the root. */
struct Node *nextPtr; /* Next in list of siblings with the
* same parent node, or NULL for end
* of list. */
Summary *summaryPtr; /* First in malloc-ed list of info
* about tags in this subtree (NULL if
* no tag info in the subtree). */
int level; /* Level of this node in the B-tree.
* 0 refers to the bottom of the tree
* (children are lines, not nodes). */
union { /* First in linked list of children. */
struct Node *nodePtr; /* Used if level > 0. */
TkTextLine *linePtr; /* Used if level == 0. */
} children;
int numChildren; /* Number of children of this node. */
int numLines; /* Total number of lines (leaves) in
* the subtree rooted here. */
} Node;
/*
* Upper and lower bounds on how many children a node may have:
* rebalance when either of these limits is exceeded. MAX_CHILDREN
* should be twice MIN_CHILDREN and MIN_CHILDREN must be >= 2.
*/
#define MAX_CHILDREN 12
#define MIN_CHILDREN 6
/*
* The data structure below defines an entire B-tree.
*/
typedef struct BTree {
Node *rootPtr; /* Pointer to root of B-tree. */
} BTree;
/*
* The structure below is used to pass information between
* TkBTreeGetTags and IncCount:
*/
typedef struct TagInfo {
int numTags; /* Number of tags for which there
* is currently information in
* tags and counts. */
int arraySize; /* Number of entries allocated for
* tags and counts. */
TkTextTag **tagPtrs; /* Array of tags seen so far.
* Malloc-ed. */
int *counts; /* Toggle count (so far) for each
* entry in tags. Malloc-ed. */
} TagInfo;
/*
* Variable that indicates whether to enable consistency checks for
* debugging.
*/
int tkBTreeDebug = 0;
/*
* Macros that determine how much space to allocate for new segments:
*/
#define CSEG_SIZE(chars) ((unsigned) (Tk_Offset(TkTextSegment, body) \
+ 1 + (chars)))
#define TSEG_SIZE ((unsigned) (Tk_Offset(TkTextSegment, body) \
+ sizeof(TkTextToggle)))
/*
* Forward declarations for procedures defined in this file:
*/
static void ChangeNodeToggleCount _ANSI_ARGS_((Node *nodePtr,
TkTextTag *tagPtr, int delta));
static void CharCheckProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr));
static int CharDeleteProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr, int treeGone));
static TkTextSegment * CharCleanupProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr));
static TkTextSegment * CharSplitProc _ANSI_ARGS_((TkTextSegment *segPtr,
int index));
static void CheckNodeConsistency _ANSI_ARGS_((Node *nodePtr));
static void CleanupLine _ANSI_ARGS_((TkTextLine *linePtr));
static void DeleteSummaries _ANSI_ARGS_((Summary *tagPtr));
static void DestroyNode _ANSI_ARGS_((Node *nodePtr));
static void IncCount _ANSI_ARGS_((TkTextTag *tagPtr, int inc,
TagInfo *tagInfoPtr));
static void Rebalance _ANSI_ARGS_((BTree *treePtr, Node *nodePtr));
static void RecomputeNodeCounts _ANSI_ARGS_((Node *nodePtr));
static TkTextSegment * SplitSeg _ANSI_ARGS_((TkTextIndex *indexPtr));
static void ToggleCheckProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr));
static TkTextSegment * ToggleCleanupProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr));
static int ToggleDeleteProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr, int treeGone));
static void ToggleLineChangeProc _ANSI_ARGS_((TkTextSegment *segPtr,
TkTextLine *linePtr));
/*
* Type record for character segments:
*/
Tk_SegType tkTextCharType = {
"character", /* name */
0, /* leftGravity */
CharSplitProc, /* splitProc */
CharDeleteProc, /* deleteProc */
CharCleanupProc, /* cleanupProc */
(Tk_SegLineChangeProc *) NULL, /* lineChangeProc */
TkTextCharLayoutProc, /* layoutProc */
CharCheckProc /* checkProc */
};
/*
* Type record for segments marking the beginning of a tagged
* range:
*/
Tk_SegType tkTextToggleOnType = {
"toggleOn", /* name */
0, /* leftGravity */
(Tk_SegSplitProc *) NULL, /* splitProc */
ToggleDeleteProc, /* deleteProc */
ToggleCleanupProc, /* cleanupProc */
ToggleLineChangeProc, /* lineChangeProc */
(Tk_SegLayoutProc *) NULL, /* layoutProc */
ToggleCheckProc /* checkProc */
};
/*
* Type record for segments marking the end of a tagged
* range:
*/
Tk_SegType tkTextToggleOffType = {
"toggleOff", /* name */
1, /* leftGravity */
(Tk_SegSplitProc *) NULL, /* splitProc */
ToggleDeleteProc, /* deleteProc */
ToggleCleanupProc, /* cleanupProc */
ToggleLineChangeProc, /* lineChangeProc */
(Tk_SegLayoutProc *) NULL, /* layoutProc */
ToggleCheckProc /* checkProc */
};
/*
*----------------------------------------------------------------------
*
* TkBTreeCreate --
*
* This procedure is called to create a new text B-tree.
*
* Results:
* The return value is a pointer to a new B-tree containing
* one line with nothing but a newline character.
*
* Side effects:
* Memory is allocated and initialized.
*
*----------------------------------------------------------------------
*/
TkTextBTree
TkBTreeCreate()
{
register BTree *treePtr;
register Node *rootPtr;
register TkTextLine *linePtr, *linePtr2;
register TkTextSegment *segPtr;
/*
* The tree will initially have two empty lines. The second line
* isn't actually part of the tree's contents, but its presence
* makes several operations easier. The tree will have one node,
* which is also the root of the tree.
*/
rootPtr = (Node *) ckalloc(sizeof(Node));
linePtr = (TkTextLine *) ckalloc(sizeof(TkTextLine));
linePtr2 = (TkTextLine *) ckalloc(sizeof(TkTextLine));
rootPtr->parentPtr = NULL;
rootPtr->nextPtr = NULL;
rootPtr->summaryPtr = NULL;
rootPtr->level = 0;
rootPtr->children.linePtr = linePtr;
rootPtr->numChildren = 2;
rootPtr->numLines = 2;
linePtr->parentPtr = rootPtr;
linePtr->nextPtr = linePtr2;
segPtr = (TkTextSegment *) ckalloc(CSEG_SIZE(1));
linePtr->segPtr = segPtr;
segPtr->typePtr = &tkTextCharType;
segPtr->nextPtr = NULL;
segPtr->size = 1;
segPtr->body.chars[0] = '\n';
segPtr->body.chars[1] = 0;
linePtr2->parentPtr = rootPtr;
linePtr2->nextPtr = NULL;
segPtr = (TkTextSegment *) ckalloc(CSEG_SIZE(1));
linePtr2->segPtr = segPtr;
segPtr->typePtr = &tkTextCharType;
segPtr->nextPtr = NULL;
segPtr->size = 1;
segPtr->body.chars[0] = '\n';
segPtr->body.chars[1] = 0;
treePtr = (BTree *) ckalloc(sizeof(BTree));
treePtr->rootPtr = rootPtr;
return (TkTextBTree) treePtr;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeDestroy --
*
* Delete a B-tree, recycling all of the storage it contains.
*
* Results:
* The tree given by treePtr is deleted. TreePtr should never
* again be used.
*
* Side effects:
* Memory is freed.
*
*----------------------------------------------------------------------
*/
void
TkBTreeDestroy(tree)
TkTextBTree tree; /* Pointer to tree to delete. */
{
BTree *treePtr = (BTree *) tree;
DestroyNode(treePtr->rootPtr);
ckfree((char *) treePtr);
}
/*
*----------------------------------------------------------------------
*
* DestroyNode --
*
* This is a recursive utility procedure used during the deletion
* of a B-tree.
*
* Results:
* None.
*
* Side effects:
* All the storage for nodePtr and its descendants is freed.
*
*----------------------------------------------------------------------
*/
static void
DestroyNode(nodePtr)
register Node *nodePtr;
{
if (nodePtr->level == 0) {
TkTextLine *linePtr;
TkTextSegment *segPtr;
while (nodePtr->children.linePtr != NULL) {
linePtr = nodePtr->children.linePtr;
nodePtr->children.linePtr = linePtr->nextPtr;
while (linePtr->segPtr != NULL) {
segPtr = linePtr->segPtr;
linePtr->segPtr = segPtr->nextPtr;
(*segPtr->typePtr->deleteProc)(segPtr, linePtr, 1);
}
ckfree((char *) linePtr);
}
} else {
register Node *childPtr;
while (nodePtr->children.nodePtr != NULL) {
childPtr = nodePtr->children.nodePtr;
nodePtr->children.nodePtr = childPtr->nextPtr;
DestroyNode(childPtr);
}
}
DeleteSummaries(nodePtr->summaryPtr);
ckfree((char *) nodePtr);
}
/*
*----------------------------------------------------------------------
*
* DeleteSummaries --
*
* Free up all of the memory in a list of tag summaries associated
* with a node.
*
* Results:
* None.
*
* Side effects:
* Storage is released.
*
*----------------------------------------------------------------------
*/
static void
DeleteSummaries(summaryPtr)
register Summary *summaryPtr; /* First in list of node's tag
* summaries. */
{
register Summary *nextPtr;
while (summaryPtr != NULL) {
nextPtr = summaryPtr->nextPtr;
ckfree((char *) summaryPtr);
summaryPtr = nextPtr;
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeInsertChars --
*
* Insert characters at a given position in a B-tree.
*
* Results:
* None.
*
* Side effects:
* Characters are added to the B-tree at the given position.
* If the string contains newlines, new lines will be added,
* which could cause the structure of the B-tree to change.
*
*----------------------------------------------------------------------
*/
void
TkBTreeInsertChars(indexPtr, string)
register TkTextIndex *indexPtr; /* Indicates where to insert text.
* When the procedure returns, this
* index is no longer valid because
* of changes to the segment
* structure. */
char *string; /* Pointer to bytes to insert (may
* contain newlines, must be null-
* terminated). */
{
register Node *nodePtr;
register TkTextSegment *prevPtr; /* The segment just before the first
* new segment (NULL means new segment
* is at beginning of line). */
TkTextSegment *curPtr; /* Current segment; new characters
* are inserted just after this one.
* NULL means insert at beginning of
* line. */
TkTextLine *linePtr; /* Current line (new segments are
* added to this line). */
register TkTextSegment *segPtr;
TkTextLine *newLinePtr;
int chunkSize; /* # characters in current chunk. */
register char *eol; /* Pointer to character just after last
* one in current chunk. */
int changeToLineCount; /* Counts change to total number of
* lines in file. */
prevPtr = SplitSeg(indexPtr);
linePtr = indexPtr->linePtr;
curPtr = prevPtr;
/*
* Chop the string up into lines and create a new segment for
* each line, plus a new line for the leftovers from the
* previous line.
*/
changeToLineCount = 0;
while (*string != 0) {
for (eol = string; *eol != 0; eol++) {
if (*eol == '\n') {
eol++;
break;
}
}
chunkSize = eol-string;
segPtr = (TkTextSegment *) ckalloc(CSEG_SIZE(chunkSize));
segPtr->typePtr = &tkTextCharType;
if (curPtr == NULL) {
segPtr->nextPtr = linePtr->segPtr;
linePtr->segPtr = segPtr;
} else {
segPtr->nextPtr = curPtr->nextPtr;
curPtr->nextPtr = segPtr;
}
segPtr->size = chunkSize;
strncpy(segPtr->body.chars, string, (size_t) chunkSize);
segPtr->body.chars[chunkSize] = 0;
curPtr = segPtr;
if (eol[-1] != '\n') {
break;
}
/*
* The chunk ended with a newline, so create a new TkTextLine
* and move the remainder of the old line to it.
*/
newLinePtr = (TkTextLine *) ckalloc(sizeof(TkTextLine));
newLinePtr->parentPtr = linePtr->parentPtr;
newLinePtr->nextPtr = linePtr->nextPtr;
linePtr->nextPtr = newLinePtr;
newLinePtr->segPtr = segPtr->nextPtr;
segPtr->nextPtr = NULL;
linePtr = newLinePtr;
curPtr = NULL;
changeToLineCount++;
string = eol;
}
/*
* Cleanup the starting line for the insertion, plus the ending
* line if it's different.
*/
CleanupLine(indexPtr->linePtr);
if (linePtr != indexPtr->linePtr) {
CleanupLine(linePtr);
}
/*
* Increment the line counts in all the parent nodes of the insertion
* point, then rebalance the tree if necessary.
*/
for (nodePtr = linePtr->parentPtr ; nodePtr != NULL;
nodePtr = nodePtr->parentPtr) {
nodePtr->numLines += changeToLineCount;
}
nodePtr = linePtr->parentPtr;
nodePtr->numChildren += changeToLineCount;
if (nodePtr->numChildren > MAX_CHILDREN) {
Rebalance((BTree *) indexPtr->tree, nodePtr);
}
if (tkBTreeDebug) {
TkBTreeCheck(indexPtr->tree);
}
}
/*
*--------------------------------------------------------------
*
* SplitSeg --
*
* This procedure is called before adding or deleting
* segments. It does three things: (a) it finds the segment
* containing indexPtr; (b) if there are several such
* segments (because some segments have zero length) then
* it picks the first segment that does not have left
* gravity; (c) if the index refers to the middle of
* a segment then it splits the segment so that the
* index now refers to the beginning of a segment.
*
* Results:
* The return value is a pointer to the segment just
* before the segment corresponding to indexPtr (as
* described above). If the segment corresponding to
* indexPtr is the first in its line then the return
* value is NULL.
*
* Side effects:
* The segment referred to by indexPtr is split unless
* indexPtr refers to its first character.
*
*--------------------------------------------------------------
*/
static TkTextSegment *
SplitSeg(indexPtr)
TkTextIndex *indexPtr; /* Index identifying position
* at which to split a segment. */
{
TkTextSegment *prevPtr, *segPtr;
int count;
for (count = indexPtr->charIndex, prevPtr = NULL,
segPtr = indexPtr->linePtr->segPtr; segPtr != NULL;
count -= segPtr->size, prevPtr = segPtr, segPtr = segPtr->nextPtr) {
if (segPtr->size > count) {
if (count == 0) {
return prevPtr;
}
segPtr = (*segPtr->typePtr->splitProc)(segPtr, count);
if (prevPtr == NULL) {
indexPtr->linePtr->segPtr = segPtr;
} else {
prevPtr->nextPtr = segPtr;
}
return segPtr;
} else if ((segPtr->size == 0) && (count == 0)
&& !segPtr->typePtr->leftGravity) {
return prevPtr;
}
}
panic("SplitSeg reached end of line!");
return NULL;
}
/*
*--------------------------------------------------------------
*
* CleanupLine --
*
* This procedure is called after modifications have been
* made to a line. It scans over all of the segments in
* the line, giving each a chance to clean itself up, e.g.
* by merging with the following segments, updating internal
* information, etc.
*
* Results:
* None.
*
* Side effects:
* Depends on what the segment-specific cleanup procedures do.
*
*--------------------------------------------------------------
*/
static void
CleanupLine(linePtr)
TkTextLine *linePtr; /* Line to be cleaned up. */
{
TkTextSegment *segPtr, **prevPtrPtr;
int anyChanges;
/*
* Make a pass over all of the segments in the line, giving each
* a chance to clean itself up. This could potentially change
* the structure of the line, e.g. by merging two segments
* together or having two segments cancel themselves; if so,
* then repeat the whole process again, since the first structure
* change might make other structure changes possible. Repeat
* until eventually there are no changes.
*/
while (1) {
anyChanges = 0;
for (prevPtrPtr = &linePtr->segPtr, segPtr = *prevPtrPtr;
segPtr != NULL;
prevPtrPtr = &(*prevPtrPtr)->nextPtr, segPtr = *prevPtrPtr) {
if (segPtr->typePtr->cleanupProc != NULL) {
*prevPtrPtr = (*segPtr->typePtr->cleanupProc)(segPtr, linePtr);
if (segPtr != *prevPtrPtr) {
anyChanges = 1;
}
}
}
if (!anyChanges) {
break;
}
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeDeleteChars --
*
* Delete a range of characters from a B-tree. The caller
* must make sure that the final newline of the B-tree is
* never deleted.
*
* Results:
* None.
*
* Side effects:
* Information is deleted from the B-tree. This can cause the
* internal structure of the B-tree to change. Note: because
* of changes to the B-tree structure, the indices pointed
* to by index1Ptr and index2Ptr should not be used after this
* procedure returns.
*
*----------------------------------------------------------------------
*/
void
TkBTreeDeleteChars(index1Ptr, index2Ptr)
register TkTextIndex *index1Ptr; /* Indicates first character that is
* to be deleted. */
register TkTextIndex *index2Ptr; /* Indicates character just after the
* last one that is to be deleted. */
{
TkTextSegment *prevPtr; /* The segment just before the start
* of the deletion range. */
TkTextSegment *lastPtr; /* The segment just after the end
* of the deletion range. */
TkTextSegment *segPtr, *nextPtr;
TkTextLine *curLinePtr;
Node *curNodePtr, *nodePtr;
/*
* Tricky point: split at index2Ptr first; otherwise the split
* at index2Ptr may invalidate segPtr and/or prevPtr.
*/
lastPtr = SplitSeg(index2Ptr);
if (lastPtr != NULL) {
lastPtr = lastPtr->nextPtr;
} else {
lastPtr = index2Ptr->linePtr->segPtr;
}
prevPtr = SplitSeg(index1Ptr);
if (prevPtr != NULL) {
segPtr = prevPtr->nextPtr;
prevPtr->nextPtr = lastPtr;
} else {
segPtr = index1Ptr->linePtr->segPtr;
index1Ptr->linePtr->segPtr = lastPtr;
}
/*
* Delete all of the segments between prevPtr and lastPtr.
*/
curLinePtr = index1Ptr->linePtr;
curNodePtr = curLinePtr->parentPtr;
while (segPtr != lastPtr) {
if (segPtr == NULL) {
TkTextLine *nextLinePtr;
/*
* We just ran off the end of a line. First find the
* next line, then go back to the old line and delete it
* (unless it's the starting line for the range).
*/
nextLinePtr = TkBTreeNextLine(curLinePtr);
if (curLinePtr != index1Ptr->linePtr) {
if (curNodePtr == index1Ptr->linePtr->parentPtr) {
index1Ptr->linePtr->nextPtr = curLinePtr->nextPtr;
} else {
curNodePtr->children.linePtr = curLinePtr->nextPtr;
}
for (nodePtr = curNodePtr; nodePtr != NULL;
nodePtr = nodePtr->parentPtr) {
nodePtr->numLines--;
}
curNodePtr->numChildren--;
ckfree((char *) curLinePtr);
}
curLinePtr = nextLinePtr;
segPtr = curLinePtr->segPtr;
/*
* If the node is empty then delete it and its parents,
* recursively upwards until a non-empty node is found.
*/
while (curNodePtr->numChildren == 0) {
Node *parentPtr;
parentPtr = curNodePtr->parentPtr;
if (parentPtr->children.nodePtr == curNodePtr) {
parentPtr->children.nodePtr = curNodePtr->nextPtr;
} else {
Node *prevNodePtr = parentPtr->children.nodePtr;
while (prevNodePtr->nextPtr != curNodePtr) {
prevNodePtr = prevNodePtr->nextPtr;
}
prevNodePtr->nextPtr = curNodePtr->nextPtr;
}
parentPtr->numChildren--;
ckfree((char *) curNodePtr);
curNodePtr = parentPtr;
}
curNodePtr = curLinePtr->parentPtr;
continue;
}
nextPtr = segPtr->nextPtr;
if ((*segPtr->typePtr->deleteProc)(segPtr, curLinePtr, 0) != 0) {
/*
* This segment refuses to die. Move it to prevPtr and
* advance prevPtr if the segment has left gravity.
*/
if (prevPtr == NULL) {
segPtr->nextPtr = index1Ptr->linePtr->segPtr;
index1Ptr->linePtr->segPtr = segPtr;
} else {
segPtr->nextPtr = prevPtr->nextPtr;
prevPtr->nextPtr = segPtr;
}
if (segPtr->typePtr->leftGravity) {
prevPtr = segPtr;
}
}
segPtr = nextPtr;
}
/*
* If the beginning and end of the deletion range are in different
* lines, join the two lines together and discard the ending line.
*/
if (index1Ptr->linePtr != index2Ptr->linePtr) {
TkTextLine *prevLinePtr;
for (segPtr = lastPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if (segPtr->typePtr->lineChangeProc != NULL) {
(*segPtr->typePtr->lineChangeProc)(segPtr, index2Ptr->linePtr);
}
}
curNodePtr = index2Ptr->linePtr->parentPtr;
for (nodePtr = curNodePtr; nodePtr != NULL;
nodePtr = nodePtr->parentPtr) {
nodePtr->numLines--;
}
curNodePtr->numChildren--;
prevLinePtr = curNodePtr->children.linePtr;
if (prevLinePtr == index2Ptr->linePtr) {
curNodePtr->children.linePtr = index2Ptr->linePtr->nextPtr;
} else {
while (prevLinePtr->nextPtr != index2Ptr->linePtr) {
prevLinePtr = prevLinePtr->nextPtr;
}
prevLinePtr->nextPtr = index2Ptr->linePtr->nextPtr;
}
ckfree((char *) index2Ptr->linePtr);
Rebalance((BTree *) index2Ptr->tree, curNodePtr);
}
/*
* Cleanup the segments in the new line.
*/
CleanupLine(index1Ptr->linePtr);
/*
* Lastly, rebalance the first node of the range.
*/
Rebalance((BTree *) index1Ptr->tree, index1Ptr->linePtr->parentPtr);
if (tkBTreeDebug) {
TkBTreeCheck(index1Ptr->tree);
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeFindLine --
*
* Find a particular line in a B-tree based on its line number.
*
* Results:
* The return value is a pointer to the line structure for the
* line whose index is "line", or NULL if no such line exists.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TkTextLine *
TkBTreeFindLine(tree, line)
TkTextBTree tree; /* B-tree in which to find line. */
int line; /* Index of desired line. */
{
BTree *treePtr = (BTree *) tree;
register Node *nodePtr;
register TkTextLine *linePtr;
int linesLeft;
nodePtr = treePtr->rootPtr;
linesLeft = line;
if ((line < 0) || (line >= nodePtr->numLines)) {
return NULL;
}
/*
* Work down through levels of the tree until a node is found at
* level 0.
*/
while (nodePtr->level != 0) {
for (nodePtr = nodePtr->children.nodePtr;
nodePtr->numLines <= linesLeft;
nodePtr = nodePtr->nextPtr) {
if (nodePtr == NULL) {
panic("TkBTreeFindLine ran out of nodes");
}
linesLeft -= nodePtr->numLines;
}
}
/*
* Work through the lines attached to the level-0 node.
*/
for (linePtr = nodePtr->children.linePtr; linesLeft > 0;
linePtr = linePtr->nextPtr) {
if (linePtr == NULL) {
panic("TkBTreeFindLine ran out of lines");
}
linesLeft -= 1;
}
return linePtr;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeNextLine --
*
* Given an existing line in a B-tree, this procedure locates the
* next line in the B-tree. This procedure is used for scanning
* through the B-tree.
*
* Results:
* The return value is a pointer to the line that immediately
* follows linePtr, or NULL if there is no such line.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TkTextLine *
TkBTreeNextLine(linePtr)
register TkTextLine *linePtr; /* Pointer to existing line in
* B-tree. */
{
register Node *nodePtr;
if (linePtr->nextPtr != NULL) {
return linePtr->nextPtr;
}
/*
* This was the last line associated with the particular parent node.
* Search up the tree for the next node, then search down from that
* node to find the first line,
*/
for (nodePtr = linePtr->parentPtr; ; nodePtr = nodePtr->parentPtr) {
if (nodePtr->nextPtr != NULL) {
nodePtr = nodePtr->nextPtr;
break;
}
if (nodePtr->parentPtr == NULL) {
return (TkTextLine *) NULL;
}
}
while (nodePtr->level > 0) {
nodePtr = nodePtr->children.nodePtr;
}
return nodePtr->children.linePtr;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeLineIndex --
*
* Given a pointer to a line in a B-tree, return the numerical
* index of that line.
*
* Results:
* The result is the index of linePtr within the tree, where 0
* corresponds to the first line in the tree.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
TkBTreeLineIndex(linePtr)
TkTextLine *linePtr; /* Pointer to existing line in
* B-tree. */
{
register TkTextLine *linePtr2;
register Node *nodePtr, *parentPtr, *nodePtr2;
int index;
/*
* First count how many lines precede this one in its level-0
* node.
*/
nodePtr = linePtr->parentPtr;
index = 0;
for (linePtr2 = nodePtr->children.linePtr; linePtr2 != linePtr;
linePtr2 = linePtr2->nextPtr) {
if (linePtr2 == NULL) {
panic("TkBTreeLineIndex couldn't find line");
}
index += 1;
}
/*
* Now work up through the levels of the tree one at a time,
* counting how many lines are in nodes preceding the current
* node.
*/
for (parentPtr = nodePtr->parentPtr ; parentPtr != NULL;
nodePtr = parentPtr, parentPtr = parentPtr->parentPtr) {
for (nodePtr2 = parentPtr->children.nodePtr; nodePtr2 != nodePtr;
nodePtr2 = nodePtr2->nextPtr) {
if (nodePtr2 == NULL) {
panic("TkBTreeLineIndex couldn't find node");
}
index += nodePtr2->numLines;
}
}
return index;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeLinkSegment --
*
* This procedure adds a new segment to a B-tree at a given
* location.
*
* Results:
* None.
*
* Side effects:
* SegPtr will be linked into its tree.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
void
TkBTreeLinkSegment(segPtr, indexPtr)
TkTextSegment *segPtr; /* Pointer to new segment to be added to
* B-tree. Should be completely initialized
* by caller except for nextPtr field. */
TkTextIndex *indexPtr; /* Where to add segment: it gets linked
* in just before the segment indicated
* here. */
{
register TkTextSegment *prevPtr;
prevPtr = SplitSeg(indexPtr);
if (prevPtr == NULL) {
segPtr->nextPtr = indexPtr->linePtr->segPtr;
indexPtr->linePtr->segPtr = segPtr;
} else {
segPtr->nextPtr = prevPtr->nextPtr;
prevPtr->nextPtr = segPtr;
}
CleanupLine(indexPtr->linePtr);
if (tkBTreeDebug) {
TkBTreeCheck(indexPtr->tree);
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeUnlinkSegment --
*
* This procedure unlinks a segment from its line in a B-tree.
*
* Results:
* None.
*
* Side effects:
* SegPtr will be unlinked from linePtr. The segment itself
* isn't modified by this procedure.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
void
TkBTreeUnlinkSegment(tree, segPtr, linePtr)
TkTextBTree tree; /* Tree containing segment. */
TkTextSegment *segPtr; /* Segment to be unlinked. */
TkTextLine *linePtr; /* Line that currently contains
* segment. */
{
register TkTextSegment *prevPtr;
if (linePtr->segPtr == segPtr) {
linePtr->segPtr = segPtr->nextPtr;
} else {
for (prevPtr = linePtr->segPtr; prevPtr->nextPtr != segPtr;
prevPtr = prevPtr->nextPtr) {
/* Empty loop body. */
}
prevPtr->nextPtr = segPtr->nextPtr;
}
CleanupLine(linePtr);
}
/*
*----------------------------------------------------------------------
*
* TkBTreeTag --
*
* Turn a given tag on or off for a given range of characters in
* a B-tree of text.
*
* Results:
* None.
*
* Side effects:
* The given tag is added to the given range of characters
* in the tree or removed from all those characters, depending
* on the "add" argument. The structure of the btree is modified
* enough that index1Ptr and index2Ptr are no longer valid after
* this procedure returns, and the indexes may be modified by
* this procedure.
*
*----------------------------------------------------------------------
*/
void
TkBTreeTag(index1Ptr, index2Ptr, tagPtr, add)
register TkTextIndex *index1Ptr; /* Indicates first character in
* range. */
register TkTextIndex *index2Ptr; /* Indicates character just after the
* last one in range. */
TkTextTag *tagPtr; /* Tag to add or remove. */
int add; /* One means add tag to the given
* range of characters; zero means
* remove the tag from the range. */
{
TkTextSegment *segPtr, *prevPtr;
TkTextSearch search;
TkTextLine *cleanupLinePtr;
int oldState;
/*
* See whether the tag is present at the start of the range. If
* the state doesn't already match what we want then add a toggle
* there.
*/
oldState = TkBTreeCharTagged(index1Ptr, tagPtr);
if ((add != 0) ^ oldState) {
segPtr = (TkTextSegment *) ckalloc(TSEG_SIZE);
segPtr->typePtr = (add) ? &tkTextToggleOnType : &tkTextToggleOffType;
prevPtr = SplitSeg(index1Ptr);
if (prevPtr == NULL) {
segPtr->nextPtr = index1Ptr->linePtr->segPtr;
index1Ptr->linePtr->segPtr = segPtr;
} else {
segPtr->nextPtr = prevPtr->nextPtr;
prevPtr->nextPtr = segPtr;
}
segPtr->size = 0;
segPtr->body.toggle.tagPtr = tagPtr;
segPtr->body.toggle.inNodeCounts = 0;
}
/*
* Scan the range of characters and delete any internal tag
* transitions. Keep track of what the old state was at the end
* of the range, and add a toggle there if it's needed.
*/
TkBTreeStartSearch(index1Ptr, index2Ptr, tagPtr, &search);
cleanupLinePtr = index1Ptr->linePtr;
while (TkBTreeNextTag(&search)) {
oldState ^= 1;
segPtr = search.segPtr;
prevPtr = search.curIndex.linePtr->segPtr;
if (prevPtr == segPtr) {
search.curIndex.linePtr->segPtr = segPtr->nextPtr;
} else {
while (prevPtr->nextPtr != segPtr) {
prevPtr = prevPtr->nextPtr;
}
prevPtr->nextPtr = segPtr->nextPtr;
}
if (segPtr->body.toggle.inNodeCounts) {
ChangeNodeToggleCount(search.curIndex.linePtr->parentPtr,
segPtr->body.toggle.tagPtr, -1);
segPtr->body.toggle.inNodeCounts = 0;
}
ckfree((char *) segPtr);
/*
* The code below is a bit tricky. After deleting a toggle
* we eventually have to call CleanupLine, in order to allow
* character segments to be merged together. To do this, we
* remember in cleanupLinePtr a line that needs to be
* cleaned up, but we don't clean it up until we've moved
* on to a different line. That way the cleanup process
* won't goof up segPtr.
*/
if (cleanupLinePtr != search.curIndex.linePtr) {
CleanupLine(cleanupLinePtr);
cleanupLinePtr = search.curIndex.linePtr;
}
}
if ((add != 0) ^ oldState) {
segPtr = (TkTextSegment *) ckalloc(TSEG_SIZE);
segPtr->typePtr = (add) ? &tkTextToggleOffType : &tkTextToggleOnType;
prevPtr = SplitSeg(index2Ptr);
if (prevPtr == NULL) {
segPtr->nextPtr = index2Ptr->linePtr->segPtr;
index2Ptr->linePtr->segPtr = segPtr;
} else {
segPtr->nextPtr = prevPtr->nextPtr;
prevPtr->nextPtr = segPtr;
}
segPtr->size = 0;
segPtr->body.toggle.tagPtr = tagPtr;
segPtr->body.toggle.inNodeCounts = 0;
}
/*
* Cleanup cleanupLinePtr and the last line of the range, if
* these are different.
*/
CleanupLine(cleanupLinePtr);
if (cleanupLinePtr != index2Ptr->linePtr) {
CleanupLine(index2Ptr->linePtr);
}
if (tkBTreeDebug) {
TkBTreeCheck(index1Ptr->tree);
}
}
/*
*----------------------------------------------------------------------
*
* ChangeNodeToggleCount --
*
* This procedure increments or decrements the toggle count for
* a particular tag in a particular node and all its ancestors.
*
* Results:
* None.
*
* Side effects:
* The toggle count for tag is adjusted up or down by "delta" in
* nodePtr.
*
*----------------------------------------------------------------------
*/
static void
ChangeNodeToggleCount(nodePtr, tagPtr, delta)
register Node *nodePtr; /* Node whose toggle count for a tag
* must be changed. */
TkTextTag *tagPtr; /* Information about tag. */
int delta; /* Amount to add to current toggle
* count for tag (may be negative). */
{
register Summary *summaryPtr, *prevPtr;
/*
* Iterate over the node and all of its ancestors.
*/
for ( ; nodePtr != NULL; nodePtr = nodePtr->parentPtr) {
/*
* See if there's already an entry for this tag for this node. If so,
* perhaps all we have to do is adjust its count.
*/
for (prevPtr = NULL, summaryPtr = nodePtr->summaryPtr;
summaryPtr != NULL;
prevPtr = summaryPtr, summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr->tagPtr != tagPtr) {
continue;
}
summaryPtr->toggleCount += delta;
if (summaryPtr->toggleCount > 0) {
goto nextAncestor;
}
if (summaryPtr->toggleCount < 0) {
panic("ChangeNodeToggleCount: negative toggle count");
}
/*
* Zero count; must remove this tag from the list.
*/
if (prevPtr == NULL) {
nodePtr->summaryPtr = summaryPtr->nextPtr;
} else {
prevPtr->nextPtr = summaryPtr->nextPtr;
}
ckfree((char *) summaryPtr);
goto nextAncestor;
}
/*
* This tag isn't in the list. Add a new entry to the list.
*/
if (delta < 0) {
panic("ChangeNodeToggleCount: negative delta, no tag entry");
}
summaryPtr = (Summary *) ckalloc(sizeof(Summary));
summaryPtr->tagPtr = tagPtr;
summaryPtr->toggleCount = delta;
summaryPtr->nextPtr = nodePtr->summaryPtr;
nodePtr->summaryPtr = summaryPtr;
nextAncestor:
continue;
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeStartSearch --
*
* This procedure sets up a search for tag transitions involving
* a given tag (or all tags) in a given range of the text.
*
* Results:
* None.
*
* Side effects:
* The information at *searchPtr is set up so that subsequent calls
* to TkBTreeNextTag will return information about the locations of
* tag transitions. Note that TkBTreeNextTag must be called to get
* the first transition.
*
*----------------------------------------------------------------------
*/
void
TkBTreeStartSearch(index1Ptr, index2Ptr, tagPtr, searchPtr)
TkTextIndex *index1Ptr; /* Search starts here. Tag toggles
* at this position will not be
* returned. */
TkTextIndex *index2Ptr; /* Search stops here. Tag toggles
* at this position *will* be
* returned. */
TkTextTag *tagPtr; /* Tag to search for. NULL means
* search for any tag. */
register TkTextSearch *searchPtr; /* Where to store information about
* search's progress. */
{
int offset;
searchPtr->curIndex = *index1Ptr;
searchPtr->segPtr = NULL;
searchPtr->nextPtr = TkTextIndexToSeg(index1Ptr, &offset);
searchPtr->curIndex.charIndex -= offset;
searchPtr->lastPtr = TkTextIndexToSeg(index2Ptr, (int *) NULL);
searchPtr->tagPtr = tagPtr;
searchPtr->linesLeft = TkBTreeLineIndex(index2Ptr->linePtr) + 1
- TkBTreeLineIndex(index1Ptr->linePtr);
searchPtr->allTags = (tagPtr == NULL);
if (searchPtr->linesLeft == 1) {
/*
* Starting and stopping segments are in the same line; mark the
* search as over immediately if the second segment is before the
* first.
*/
if (index1Ptr->charIndex >= index2Ptr->charIndex) {
searchPtr->linesLeft = 0;
}
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeNextTag --
*
* Once a tag search has begun, successive calls to this procedure
* return successive tag toggles. Note: it is NOT SAFE to call this
* procedure if characters have been inserted into or deleted from
* the B-tree since the call to TkBTreeStartSearch.
*
* Results:
* The return value is 1 if another toggle was found that met the
* criteria specified in the call to TkBTreeStartSearch; in this
* case searchPtr->curIndex gives the toggle's position and
* searchPtr->curTagPtr points to its segment. 0 is returned if
* no more matching tag transitions were found; in this case
* searchPtr->curIndex is the same as searchPtr->stopIndex.
*
* Side effects:
* Information in *searchPtr is modified to update the state of the
* search and indicate where the next tag toggle is located.
*
*----------------------------------------------------------------------
*/
int
TkBTreeNextTag(searchPtr)
register TkTextSearch *searchPtr; /* Information about search in
* progress; must have been set up by
* call to TkBTreeStartSearch. */
{
register TkTextSegment *segPtr;
register Node *nodePtr;
register Summary *summaryPtr;
if (searchPtr->linesLeft <= 0) {
goto searchOver;
}
/*
* The outermost loop iterates over lines that may potentially contain
* a relevant tag transition, starting from the current segment in
* the current line.
*/
segPtr = searchPtr->nextPtr;
while (1) {
/*
* Check for more tags on the current line.
*/
for ( ; segPtr != NULL; segPtr = segPtr->nextPtr) {
if (segPtr == searchPtr->lastPtr) {
goto searchOver;
}
if (((segPtr->typePtr == &tkTextToggleOnType)
|| (segPtr->typePtr == &tkTextToggleOffType))
&& (searchPtr->allTags
|| (segPtr->body.toggle.tagPtr == searchPtr->tagPtr))) {
searchPtr->segPtr = segPtr;
searchPtr->nextPtr = segPtr->nextPtr;
searchPtr->tagPtr = segPtr->body.toggle.tagPtr;
return 1;
}
searchPtr->curIndex.charIndex += segPtr->size;
}
/*
* See if there are more lines associated with the current parent
* node. If so, go back to the top of the loop to search the next
* one.
*/
nodePtr = searchPtr->curIndex.linePtr->parentPtr;
searchPtr->curIndex.linePtr = searchPtr->curIndex.linePtr->nextPtr;
searchPtr->linesLeft--;
if (searchPtr->linesLeft <= 0) {
goto searchOver;
}
if (searchPtr->curIndex.linePtr != NULL) {
segPtr = searchPtr->curIndex.linePtr->segPtr;
searchPtr->curIndex.charIndex = 0;
continue;
}
/*
* Search across and up through the B-tree's node hierarchy looking
* for the next node that has a relevant tag transition somewhere in
* its subtree. Be sure to update linesLeft as we skip over large
* chunks of lines.
*/
while (1) {
while (nodePtr->nextPtr == NULL) {
if (nodePtr->parentPtr == NULL) {
goto searchOver;
}
nodePtr = nodePtr->parentPtr;
}
nodePtr = nodePtr->nextPtr;
for (summaryPtr = nodePtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
if ((searchPtr->allTags) ||
(summaryPtr->tagPtr == searchPtr->tagPtr)) {
goto gotNodeWithTag;
}
}
searchPtr->linesLeft -= nodePtr->numLines;
}
/*
* At this point we've found a subtree that has a relevant tag
* transition. Now search down (and across) through that subtree
* to find the first level-0 node that has a relevant tag transition.
*/
gotNodeWithTag:
while (nodePtr->level > 0) {
for (nodePtr = nodePtr->children.nodePtr; ;
nodePtr = nodePtr->nextPtr) {
for (summaryPtr = nodePtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
if ((searchPtr->allTags)
|| (summaryPtr->tagPtr == searchPtr->tagPtr)) {
goto nextChild;
}
}
searchPtr->linesLeft -= nodePtr->numLines;
if (nodePtr->nextPtr == NULL) {
panic("TkBTreeNextTag found incorrect tag summary info.");
}
}
nextChild:
continue;
}
/*
* Now we're down to a level-0 node that contains a line that contains
* a relevant tag transition. Set up line information and go back to
* the beginning of the loop to search through lines.
*/
searchPtr->curIndex.linePtr = nodePtr->children.linePtr;
searchPtr->curIndex.charIndex = 0;
segPtr = searchPtr->curIndex.linePtr->segPtr;
if (searchPtr->linesLeft <= 0) {
goto searchOver;
}
continue;
}
searchOver:
searchPtr->linesLeft = 0;
searchPtr->segPtr = NULL;
return 0;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeCharTagged --
*
* Determine whether a particular character has a particular tag.
*
* Results:
* The return value is 1 if the given tag is in effect at the
* character given by linePtr and ch, and 0 otherwise.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
TkBTreeCharTagged(indexPtr, tagPtr)
TkTextIndex *indexPtr; /* Indicates a character position at
* which to check for a tag. */
TkTextTag *tagPtr; /* Tag of interest. */
{
register Node *nodePtr;
register TkTextLine *siblingLinePtr;
register TkTextSegment *segPtr;
TkTextSegment *toggleSegPtr;
int toggles, index;
/*
* Check for toggles for the tag in indexPtr's line but before
* indexPtr. If there is one, its type indicates whether or
* not the character is tagged.
*/
toggleSegPtr = NULL;
for (index = 0, segPtr = indexPtr->linePtr->segPtr;
(index + segPtr->size) <= indexPtr->charIndex;
index += segPtr->size, segPtr = segPtr->nextPtr) {
if (((segPtr->typePtr == &tkTextToggleOnType)
|| (segPtr->typePtr == &tkTextToggleOffType))
&& (segPtr->body.toggle.tagPtr == tagPtr)) {
toggleSegPtr = segPtr;
}
}
if (toggleSegPtr != NULL) {
return (toggleSegPtr->typePtr == &tkTextToggleOnType);
}
/*
* No toggle in this line. Look for toggles for the tag in lines
* that are predecessors of indexPtr->linePtr but under the same
* level-0 node.
*/
toggles = 0;
for (siblingLinePtr = indexPtr->linePtr->parentPtr->children.linePtr;
siblingLinePtr != indexPtr->linePtr;
siblingLinePtr = siblingLinePtr->nextPtr) {
for (segPtr = siblingLinePtr->segPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if (((segPtr->typePtr == &tkTextToggleOnType)
|| (segPtr->typePtr == &tkTextToggleOffType))
&& (segPtr->body.toggle.tagPtr == tagPtr)) {
toggleSegPtr = segPtr;
}
}
}
if (toggleSegPtr != NULL) {
return (toggleSegPtr->typePtr == &tkTextToggleOnType);
}
/*
* No toggle in this node. Scan upwards through the ancestors of
* this node, counting the number of toggles of the given tag in
* siblings that precede that node.
*/
toggles = 0;
for (nodePtr = indexPtr->linePtr->parentPtr; nodePtr->parentPtr != NULL;
nodePtr = nodePtr->parentPtr) {
register Node *siblingPtr;
register Summary *summaryPtr;
for (siblingPtr = nodePtr->parentPtr->children.nodePtr;
siblingPtr != nodePtr; siblingPtr = siblingPtr->nextPtr) {
for (summaryPtr = siblingPtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr->tagPtr == tagPtr) {
toggles += summaryPtr->toggleCount;
}
}
}
}
/*
* An odd number of toggles means that the tag is present at the
* given point.
*/
return toggles & 1;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeGetTags --
*
* Return information about all of the tags that are associated
* with a particular character in a B-tree of text.
*
* Results:
* The return value is a malloc-ed array containing pointers to
* information for each of the tags that is associated with
* the character at the position given by linePtr and ch. The
* word at *numTagsPtr is filled in with the number of pointers
* in the array. It is up to the caller to free the array by
* passing it to free. If there are no tags at the given character
* then a NULL pointer is returned and *numTagsPtr will be set to 0.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
TkTextTag **
TkBTreeGetTags(indexPtr, numTagsPtr)
TkTextIndex *indexPtr; /* Indicates a particular position in
* the B-tree. */
int *numTagsPtr; /* Store number of tags found at this
* location. */
{
register Node *nodePtr;
register TkTextLine *siblingLinePtr;
register TkTextSegment *segPtr;
int src, dst, index;
TagInfo tagInfo;
#define NUM_TAG_INFOS 10
tagInfo.numTags = 0;
tagInfo.arraySize = NUM_TAG_INFOS;
tagInfo.tagPtrs = (TkTextTag **) ckalloc((unsigned)
NUM_TAG_INFOS*sizeof(TkTextTag *));
tagInfo.counts = (int *) ckalloc((unsigned)
NUM_TAG_INFOS*sizeof(int));
/*
* Record tag toggles within the line of indexPtr but preceding
* indexPtr.
*/
for (index = 0, segPtr = indexPtr->linePtr->segPtr;
(index + segPtr->size) <= indexPtr->charIndex;
index += segPtr->size, segPtr = segPtr->nextPtr) {
if ((segPtr->typePtr == &tkTextToggleOnType)
|| (segPtr->typePtr == &tkTextToggleOffType)) {
IncCount(segPtr->body.toggle.tagPtr, 1, &tagInfo);
}
}
/*
* Record toggles for tags in lines that are predecessors of
* indexPtr->linePtr but under the same level-0 node.
*/
for (siblingLinePtr = indexPtr->linePtr->parentPtr->children.linePtr;
siblingLinePtr != indexPtr->linePtr;
siblingLinePtr = siblingLinePtr->nextPtr) {
for (segPtr = siblingLinePtr->segPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if ((segPtr->typePtr == &tkTextToggleOnType)
|| (segPtr->typePtr == &tkTextToggleOffType)) {
IncCount(segPtr->body.toggle.tagPtr, 1, &tagInfo);
}
}
}
/*
* For each node in the ancestry of this line, record tag toggles
* for all siblings that precede that node.
*/
for (nodePtr = indexPtr->linePtr->parentPtr; nodePtr->parentPtr != NULL;
nodePtr = nodePtr->parentPtr) {
register Node *siblingPtr;
register Summary *summaryPtr;
for (siblingPtr = nodePtr->parentPtr->children.nodePtr;
siblingPtr != nodePtr; siblingPtr = siblingPtr->nextPtr) {
for (summaryPtr = siblingPtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr->toggleCount & 1) {
IncCount(summaryPtr->tagPtr, summaryPtr->toggleCount,
&tagInfo);
}
}
}
}
/*
* Go through the tag information and squash out all of the tags
* that have even toggle counts (these tags exist before the point
* of interest, but not at the desired character itself).
*/
for (src = 0, dst = 0; src < tagInfo.numTags; src++) {
if (tagInfo.counts[src] & 1) {
tagInfo.tagPtrs[dst] = tagInfo.tagPtrs[src];
dst++;
}
}
*numTagsPtr = dst;
ckfree((char *) tagInfo.counts);
if (dst == 0) {
ckfree((char *) tagInfo.tagPtrs);
return NULL;
}
return tagInfo.tagPtrs;
}
/*
*----------------------------------------------------------------------
*
* IncCount --
*
* This is a utility procedure used by TkBTreeGetTags. It
* increments the count for a particular tag, adding a new
* entry for that tag if there wasn't one previously.
*
* Results:
* None.
*
* Side effects:
* The information at *tagInfoPtr may be modified, and the arrays
* may be reallocated to make them larger.
*
*----------------------------------------------------------------------
*/
static void
IncCount(tagPtr, inc, tagInfoPtr)
TkTextTag *tagPtr; /* Handle for tag. */
int inc; /* Amount by which to increment tag count. */
TagInfo *tagInfoPtr; /* Holds cumulative information about tags;
* increment count here. */
{
register TkTextTag **tagPtrPtr;
int count;
for (tagPtrPtr = tagInfoPtr->tagPtrs, count = tagInfoPtr->numTags;
count > 0; tagPtrPtr++, count--) {
if (*tagPtrPtr == tagPtr) {
tagInfoPtr->counts[tagInfoPtr->numTags-count] += inc;
return;
}
}
/*
* There isn't currently an entry for this tag, so we have to
* make a new one. If the arrays are full, then enlarge the
* arrays first.
*/
if (tagInfoPtr->numTags == tagInfoPtr->arraySize) {
TkTextTag **newTags;
int *newCounts, newSize;
newSize = 2*tagInfoPtr->arraySize;
newTags = (TkTextTag **) ckalloc((unsigned)
(newSize*sizeof(TkTextTag *)));
memcpy((VOID *) newTags, (VOID *) tagInfoPtr->tagPtrs,
tagInfoPtr->arraySize * sizeof(TkTextTag *));
ckfree((char *) tagInfoPtr->tagPtrs);
tagInfoPtr->tagPtrs = newTags;
newCounts = (int *) ckalloc((unsigned) (newSize*sizeof(int)));
memcpy((VOID *) newCounts, (VOID *) tagInfoPtr->counts,
tagInfoPtr->arraySize * sizeof(int));
ckfree((char *) tagInfoPtr->counts);
tagInfoPtr->counts = newCounts;
tagInfoPtr->arraySize = newSize;
}
tagInfoPtr->tagPtrs[tagInfoPtr->numTags] = tagPtr;
tagInfoPtr->counts[tagInfoPtr->numTags] = inc;
tagInfoPtr->numTags++;
}
/*
*----------------------------------------------------------------------
*
* TkBTreeCheck --
*
* This procedure runs a set of consistency checks over a B-tree
* and panics if any inconsistencies are found.
*
* Results:
* None.
*
* Side effects:
* If a structural defect is found, the procedure panics with an
* error message.
*
*----------------------------------------------------------------------
*/
void
TkBTreeCheck(tree)
TkTextBTree tree; /* Tree to check. */
{
BTree *treePtr = (BTree *) tree;
register Summary *summaryPtr;
register Node *nodePtr;
register TkTextLine *linePtr;
register TkTextSegment *segPtr;
/*
* Make sure that overall there is an even count of tag transitions
* for the whole tree.
*/
for (summaryPtr = treePtr->rootPtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr->toggleCount & 1) {
panic("TkBTreeCheck found odd toggle count for \"%s\" (%d)",
summaryPtr->tagPtr->name, summaryPtr->toggleCount);
}
}
/*
* Call a recursive procedure to do the main body of checks.
*/
nodePtr = treePtr->rootPtr;
CheckNodeConsistency(treePtr->rootPtr);
/*
* Make sure that there are at least two lines in the text and
* that the last line has no characters except a newline.
*/
if (nodePtr->numLines < 2) {
panic("TkBTreeCheck: less than 2 lines in tree");
}
while (nodePtr->level > 0) {
nodePtr = nodePtr->children.nodePtr;
while (nodePtr->nextPtr != NULL) {
nodePtr = nodePtr->nextPtr;
}
}
linePtr = nodePtr->children.linePtr;
while (linePtr->nextPtr != NULL) {
linePtr = linePtr->nextPtr;
}
segPtr = linePtr->segPtr;
while ((segPtr->typePtr == &tkTextToggleOffType)
|| (segPtr->typePtr == &tkTextRightMarkType)
|| (segPtr->typePtr == &tkTextLeftMarkType)) {
/*
* It's OK to toggle a tag off in the last line, but
* not to start a new range. It's also OK to have marks
* in the last line.
*/
segPtr = segPtr->nextPtr;
}
if (segPtr->typePtr != &tkTextCharType) {
panic("TkBTreeCheck: last line has bogus segment type");
}
if (segPtr->nextPtr != NULL) {
panic("TkBTreeCheck: last line has too many segments");
}
if (segPtr->size != 1) {
panic("TkBTreeCheck: last line has wrong # characters: %d",
segPtr->size);
}
if ((segPtr->body.chars[0] != '\n') || (segPtr->body.chars[1] != 0)) {
panic("TkBTreeCheck: last line had bad value: %s",
segPtr->body.chars);
}
}
/*
*----------------------------------------------------------------------
*
* CheckNodeConsistency --
*
* This procedure is called as part of consistency checking for
* B-trees: it checks several aspects of a node and also runs
* checks recursively on the node's children.
*
* Results:
* None.
*
* Side effects:
* If anything suspicious is found in the tree structure, the
* procedure panics.
*
*----------------------------------------------------------------------
*/
static void
CheckNodeConsistency(nodePtr)
register Node *nodePtr; /* Node whose subtree should be
* checked. */
{
register Node *childNodePtr;
register Summary *summaryPtr, *summaryPtr2;
register TkTextLine *linePtr;
register TkTextSegment *segPtr;
int numChildren, numLines, toggleCount, minChildren;
if (nodePtr->parentPtr != NULL) {
minChildren = MIN_CHILDREN;
} else if (nodePtr->level > 0) {
minChildren = 2;
} else {
minChildren = 1;
}
if ((nodePtr->numChildren < minChildren)
|| (nodePtr->numChildren > MAX_CHILDREN)) {
panic("CheckNodeConsistency: bad child count (%d)",
nodePtr->numChildren);
}
numChildren = 0;
numLines = 0;
if (nodePtr->level == 0) {
for (linePtr = nodePtr->children.linePtr; linePtr != NULL;
linePtr = linePtr->nextPtr) {
if (linePtr->parentPtr != nodePtr) {
panic("CheckNodeConsistency: line doesn't point to parent");
}
if (linePtr->segPtr == NULL) {
panic("CheckNodeConsistency: line has no segments");
}
for (segPtr = linePtr->segPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if (segPtr->typePtr->checkProc != NULL) {
(*segPtr->typePtr->checkProc)(segPtr, linePtr);
}
if ((segPtr->size == 0) && (!segPtr->typePtr->leftGravity)
&& (segPtr->nextPtr != NULL)
&& (segPtr->nextPtr->size == 0)
&& (segPtr->nextPtr->typePtr->leftGravity)) {
panic("CheckNodeConsistency: wrong segment order for gravity");
}
if ((segPtr->nextPtr == NULL)
&& (segPtr->typePtr != &tkTextCharType)) {
panic("CheckNodeConsistency: line ended with wrong type");
}
}
numChildren++;
numLines++;
}
} else {
for (childNodePtr = nodePtr->children.nodePtr; childNodePtr != NULL;
childNodePtr = childNodePtr->nextPtr) {
if (childNodePtr->parentPtr != nodePtr) {
panic("CheckNodeConsistency: node doesn't point to parent");
}
if (childNodePtr->level != (nodePtr->level-1)) {
panic("CheckNodeConsistency: level mismatch (%d %d)",
nodePtr->level, childNodePtr->level);
}
CheckNodeConsistency(childNodePtr);
for (summaryPtr = childNodePtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
for (summaryPtr2 = nodePtr->summaryPtr; ;
summaryPtr2 = summaryPtr2->nextPtr) {
if (summaryPtr2 == NULL) {
panic("CheckNodeConsistency: node tag \"%s\" not %s",
summaryPtr->tagPtr->name,
"present in parent summaries");
}
if (summaryPtr->tagPtr == summaryPtr2->tagPtr) {
break;
}
}
}
numChildren++;
numLines += childNodePtr->numLines;
}
}
if (numChildren != nodePtr->numChildren) {
panic("CheckNodeConsistency: mismatch in numChildren (%d %d)",
numChildren, nodePtr->numChildren);
}
if (numLines != nodePtr->numLines) {
panic("CheckNodeConsistency: mismatch in numLines (%d %d)",
numLines, nodePtr->numLines);
}
for (summaryPtr = nodePtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
toggleCount = 0;
if (nodePtr->level == 0) {
for (linePtr = nodePtr->children.linePtr; linePtr != NULL;
linePtr = linePtr->nextPtr) {
for (segPtr = linePtr->segPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if ((segPtr->typePtr != &tkTextToggleOnType)
&& (segPtr->typePtr != &tkTextToggleOffType)) {
continue;
}
if (segPtr->body.toggle.tagPtr == summaryPtr->tagPtr) {
toggleCount ++;
}
}
}
} else {
for (childNodePtr = nodePtr->children.nodePtr;
childNodePtr != NULL;
childNodePtr = childNodePtr->nextPtr) {
for (summaryPtr2 = childNodePtr->summaryPtr;
summaryPtr2 != NULL;
summaryPtr2 = summaryPtr2->nextPtr) {
if (summaryPtr2->tagPtr == summaryPtr->tagPtr) {
toggleCount += summaryPtr2->toggleCount;
}
}
}
}
if (toggleCount != summaryPtr->toggleCount) {
panic("CheckNodeConsistency: mismatch in toggleCount (%d %d)",
toggleCount, summaryPtr->toggleCount);
}
for (summaryPtr2 = summaryPtr->nextPtr; summaryPtr2 != NULL;
summaryPtr2 = summaryPtr2->nextPtr) {
if (summaryPtr2->tagPtr == summaryPtr->tagPtr) {
panic("CheckNodeConsistency: duplicated node tag: %s",
summaryPtr->tagPtr->name);
}
}
}
}
/*
*----------------------------------------------------------------------
*
* Rebalance --
*
* This procedure is called when a node of a B-tree appears to be
* out of balance (too many children, or too few). It rebalances
* that node and all of its ancestors in the tree.
*
* Results:
* None.
*
* Side effects:
* The internal structure of treePtr may change.
*
*----------------------------------------------------------------------
*/
static void
Rebalance(treePtr, nodePtr)
BTree *treePtr; /* Tree that is being rebalanced. */
register Node *nodePtr; /* Node that may be out of balance. */
{
/*
* Loop over the entire ancestral chain of the node, working up
* through the tree one node at a time until the root node has
* been processed.
*/
for ( ; nodePtr != NULL; nodePtr = nodePtr->parentPtr) {
register Node *newPtr, *childPtr;
register TkTextLine *linePtr;
int i;
/*
* Check to see if the node has too many children. If it does,
* then split off all but the first MIN_CHILDREN into a separate
* node following the original one. Then repeat until the
* node has a decent size.
*/
if (nodePtr->numChildren > MAX_CHILDREN) {
while (1) {
/*
* If the node being split is the root node, then make a
* new root node above it first.
*/
if (nodePtr->parentPtr == NULL) {
newPtr = (Node *) ckalloc(sizeof(Node));
newPtr->parentPtr = NULL;
newPtr->nextPtr = NULL;
newPtr->summaryPtr = NULL;
newPtr->level = nodePtr->level + 1;
newPtr->children.nodePtr = nodePtr;
newPtr->numChildren = 1;
newPtr->numLines = nodePtr->numLines;
RecomputeNodeCounts(newPtr);
treePtr->rootPtr = newPtr;
}
newPtr = (Node *) ckalloc(sizeof(Node));
newPtr->parentPtr = nodePtr->parentPtr;
newPtr->nextPtr = nodePtr->nextPtr;
nodePtr->nextPtr = newPtr;
newPtr->summaryPtr = NULL;
newPtr->level = nodePtr->level;
newPtr->numChildren = nodePtr->numChildren - MIN_CHILDREN;
if (nodePtr->level == 0) {
for (i = MIN_CHILDREN-1,
linePtr = nodePtr->children.linePtr;
i > 0; i--, linePtr = linePtr->nextPtr) {
/* Empty loop body. */
}
newPtr->children.linePtr = linePtr->nextPtr;
linePtr->nextPtr = NULL;
} else {
for (i = MIN_CHILDREN-1,
childPtr = nodePtr->children.nodePtr;
i > 0; i--, childPtr = childPtr->nextPtr) {
/* Empty loop body. */
}
newPtr->children.nodePtr = childPtr->nextPtr;
childPtr->nextPtr = NULL;
}
RecomputeNodeCounts(nodePtr);
nodePtr->parentPtr->numChildren++;
nodePtr = newPtr;
if (nodePtr->numChildren <= MAX_CHILDREN) {
RecomputeNodeCounts(nodePtr);
break;
}
}
}
while (nodePtr->numChildren < MIN_CHILDREN) {
register Node *otherPtr;
Node *halfwayNodePtr = NULL; /* Initialization needed only */
TkTextLine *halfwayLinePtr = NULL; /* to prevent cc warnings. */
int totalChildren, firstChildren, i;
/*
* Too few children for this node. If this is the root then,
* it's OK for it to have less than MIN_CHILDREN children
* as long as it's got at least two. If it has only one
* (and isn't at level 0), then chop the root node out of
* the tree and use its child as the new root.
*/
if (nodePtr->parentPtr == NULL) {
if ((nodePtr->numChildren == 1) && (nodePtr->level > 0)) {
treePtr->rootPtr = nodePtr->children.nodePtr;
treePtr->rootPtr->parentPtr = NULL;
DeleteSummaries(nodePtr->summaryPtr);
ckfree((char *) nodePtr);
}
return;
}
/*
* Not the root. Make sure that there are siblings to
* balance with.
*/
if (nodePtr->parentPtr->numChildren < 2) {
Rebalance(treePtr, nodePtr->parentPtr);
continue;
}
/*
* Find a sibling neighbor to borrow from, and arrange for
* nodePtr to be the earlier of the pair.
*/
if (nodePtr->nextPtr == NULL) {
for (otherPtr = nodePtr->parentPtr->children.nodePtr;
otherPtr->nextPtr != nodePtr;
otherPtr = otherPtr->nextPtr) {
/* Empty loop body. */
}
nodePtr = otherPtr;
}
otherPtr = nodePtr->nextPtr;
/*
* We're going to either merge the two siblings together
* into one node or redivide the children among them to
* balance their loads. As preparation, join their two
* child lists into a single list and remember the half-way
* point in the list.
*/
totalChildren = nodePtr->numChildren + otherPtr->numChildren;
firstChildren = totalChildren/2;
if (nodePtr->children.nodePtr == NULL) {
nodePtr->children = otherPtr->children;
otherPtr->children.nodePtr = NULL;
otherPtr->children.linePtr = NULL;
}
if (nodePtr->level == 0) {
register TkTextLine *linePtr;
for (linePtr = nodePtr->children.linePtr, i = 1;
linePtr->nextPtr != NULL;
linePtr = linePtr->nextPtr, i++) {
if (i == firstChildren) {
halfwayLinePtr = linePtr;
}
}
linePtr->nextPtr = otherPtr->children.linePtr;
while (i <= firstChildren) {
halfwayLinePtr = linePtr;
linePtr = linePtr->nextPtr;
i++;
}
} else {
register Node *childPtr;
for (childPtr = nodePtr->children.nodePtr, i = 1;
childPtr->nextPtr != NULL;
childPtr = childPtr->nextPtr, i++) {
if (i <= firstChildren) {
if (i == firstChildren) {
halfwayNodePtr = childPtr;
}
}
}
childPtr->nextPtr = otherPtr->children.nodePtr;
while (i <= firstChildren) {
halfwayNodePtr = childPtr;
childPtr = childPtr->nextPtr;
i++;
}
}
/*
* If the two siblings can simply be merged together, do it.
*/
if (totalChildren <= MAX_CHILDREN) {
RecomputeNodeCounts(nodePtr);
nodePtr->nextPtr = otherPtr->nextPtr;
nodePtr->parentPtr->numChildren--;
DeleteSummaries(otherPtr->summaryPtr);
ckfree((char *) otherPtr);
continue;
}
/*
* The siblings can't be merged, so just divide their
* children evenly between them.
*/
if (nodePtr->level == 0) {
otherPtr->children.linePtr = halfwayLinePtr->nextPtr;
halfwayLinePtr->nextPtr = NULL;
} else {
otherPtr->children.nodePtr = halfwayNodePtr->nextPtr;
halfwayNodePtr->nextPtr = NULL;
}
RecomputeNodeCounts(nodePtr);
RecomputeNodeCounts(otherPtr);
}
}
}
/*
*----------------------------------------------------------------------
*
* RecomputeNodeCounts --
*
* This procedure is called to recompute all the counts in a node
* (tags, child information, etc.) by scanning the information in
* its descendants. This procedure is called during rebalancing
* when a node's child structure has changed.
*
* Results:
* None.
*
* Side effects:
* The tag counts for nodePtr are modified to reflect its current
* child structure, as are its numChildren and numLines fields.
* Also, all of the childrens' parentPtr fields are made to point
* to nodePtr.
*
*----------------------------------------------------------------------
*/
static void
RecomputeNodeCounts(nodePtr)
register Node *nodePtr; /* Node whose tag summary information
* must be recomputed. */
{
register Summary *summaryPtr, *summaryPtr2;
register Node *childPtr;
register TkTextLine *linePtr;
register TkTextSegment *segPtr;
TkTextTag *tagPtr;
/*
* Zero out all the existing counts for the node, but don't delete
* the existing Summary records (most of them will probably be reused).
*/
for (summaryPtr = nodePtr->summaryPtr; summaryPtr != NULL;
summaryPtr = summaryPtr->nextPtr) {
summaryPtr->toggleCount = 0;
}
nodePtr->numChildren = 0;
nodePtr->numLines = 0;
/*
* Scan through the children, adding the childrens' tag counts into
* the node's tag counts and adding new Summary structures if
* necessary.
*/
if (nodePtr->level == 0) {
for (linePtr = nodePtr->children.linePtr; linePtr != NULL;
linePtr = linePtr->nextPtr) {
nodePtr->numChildren++;
nodePtr->numLines++;
linePtr->parentPtr = nodePtr;
for (segPtr = linePtr->segPtr; segPtr != NULL;
segPtr = segPtr->nextPtr) {
if (((segPtr->typePtr != &tkTextToggleOnType)
&& (segPtr->typePtr != &tkTextToggleOffType))
|| !(segPtr->body.toggle.inNodeCounts)) {
continue;
}
tagPtr = segPtr->body.toggle.tagPtr;
for (summaryPtr = nodePtr->summaryPtr; ;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr == NULL) {
summaryPtr = (Summary *) ckalloc(sizeof(Summary));
summaryPtr->tagPtr = tagPtr;
summaryPtr->toggleCount = 1;
summaryPtr->nextPtr = nodePtr->summaryPtr;
nodePtr->summaryPtr = summaryPtr;
break;
}
if (summaryPtr->tagPtr == tagPtr) {
summaryPtr->toggleCount++;
break;
}
}
}
}
} else {
for (childPtr = nodePtr->children.nodePtr; childPtr != NULL;
childPtr = childPtr->nextPtr) {
nodePtr->numChildren++;
nodePtr->numLines += childPtr->numLines;
childPtr->parentPtr = nodePtr;
for (summaryPtr2 = childPtr->summaryPtr; summaryPtr2 != NULL;
summaryPtr2 = summaryPtr2->nextPtr) {
for (summaryPtr = nodePtr->summaryPtr; ;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr == NULL) {
summaryPtr = (Summary *) ckalloc(sizeof(Summary));
summaryPtr->tagPtr = summaryPtr2->tagPtr;
summaryPtr->toggleCount = summaryPtr2->toggleCount;
summaryPtr->nextPtr = nodePtr->summaryPtr;
nodePtr->summaryPtr = summaryPtr;
break;
}
if (summaryPtr->tagPtr == summaryPtr2->tagPtr) {
summaryPtr->toggleCount += summaryPtr2->toggleCount;
break;
}
}
}
}
}
/*
* Scan through the node's tag records again and delete any Summary
* records that still have a zero count.
*/
summaryPtr2 = NULL;
for (summaryPtr = nodePtr->summaryPtr; summaryPtr != NULL; ) {
if (summaryPtr->toggleCount > 0) {
summaryPtr2 = summaryPtr;
summaryPtr = summaryPtr->nextPtr;
continue;
}
if (summaryPtr2 != NULL) {
summaryPtr2->nextPtr = summaryPtr->nextPtr;
ckfree((char *) summaryPtr);
summaryPtr = summaryPtr2->nextPtr;
} else {
nodePtr->summaryPtr = summaryPtr->nextPtr;
ckfree((char *) summaryPtr);
summaryPtr = nodePtr->summaryPtr;
}
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeNumLines --
*
* This procedure returns a count of the number of lines of
* text present in a given B-tree.
*
* Results:
* The return value is a count of the number of usable lines
* in tree (i.e. it doesn't include the dummy line that is just
* used to mark the end of the tree).
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
TkBTreeNumLines(tree)
TkTextBTree tree; /* Information about tree. */
{
BTree *treePtr = (BTree *) tree;
return treePtr->rootPtr->numLines - 1;
}
/*
*--------------------------------------------------------------
*
* CharSplitProc --
*
* This procedure implements splitting for character segments.
*
* Results:
* The return value is a pointer to a chain of two segments
* that have the same characters as segPtr except split
* among the two segments.
*
* Side effects:
* Storage for segPtr is freed.
*
*--------------------------------------------------------------
*/
static TkTextSegment *
CharSplitProc(segPtr, index)
TkTextSegment *segPtr; /* Pointer to segment to split. */
int index; /* Position within segment at which
* to split. */
{
TkTextSegment *newPtr1, *newPtr2;
newPtr1 = (TkTextSegment *) ckalloc(CSEG_SIZE(index));
newPtr2 = (TkTextSegment *) ckalloc(
CSEG_SIZE(segPtr->size - index));
newPtr1->typePtr = &tkTextCharType;
newPtr1->nextPtr = newPtr2;
newPtr1->size = index;
strncpy(newPtr1->body.chars, segPtr->body.chars, (size_t) index);
newPtr1->body.chars[index] = 0;
newPtr2->typePtr = &tkTextCharType;
newPtr2->nextPtr = segPtr->nextPtr;
newPtr2->size = segPtr->size - index;
strcpy(newPtr2->body.chars, segPtr->body.chars + index);
ckfree((char*) segPtr);
return newPtr1;
}
/*
*--------------------------------------------------------------
*
* CharCleanupProc --
*
* This procedure merges adjacent character segments into
* a single character segment, if possible.
*
* Results:
* The return value is a pointer to the first segment in
* the (new) list of segments that used to start with segPtr.
*
* Side effects:
* Storage for the segments may be allocated and freed.
*
*--------------------------------------------------------------
*/
/* ARGSUSED */
static TkTextSegment *
CharCleanupProc(segPtr, linePtr)
TkTextSegment *segPtr; /* Pointer to first of two adjacent
* segments to join. */
TkTextLine *linePtr; /* Line containing segments (not
* used). */
{
TkTextSegment *segPtr2, *newPtr;
segPtr2 = segPtr->nextPtr;
if ((segPtr2 == NULL) || (segPtr2->typePtr != &tkTextCharType)) {
return segPtr;
}
newPtr = (TkTextSegment *) ckalloc(CSEG_SIZE(
segPtr->size + segPtr2->size));
newPtr->typePtr = &tkTextCharType;
newPtr->nextPtr = segPtr2->nextPtr;
newPtr->size = segPtr->size + segPtr2->size;
strcpy(newPtr->body.chars, segPtr->body.chars);
strcpy(newPtr->body.chars + segPtr->size, segPtr2->body.chars);
ckfree((char*) segPtr);
ckfree((char*) segPtr2);
return newPtr;
}
/*
*--------------------------------------------------------------
*
* CharDeleteProc --
*
* This procedure is invoked to delete a character segment.
*
* Results:
* Always returns 0 to indicate that the segment was deleted.
*
* Side effects:
* Storage for the segment is freed.
*
*--------------------------------------------------------------
*/
/* ARGSUSED */
static int
CharDeleteProc(segPtr, linePtr, treeGone)
TkTextSegment *segPtr; /* Segment to delete. */
TkTextLine *linePtr; /* Line containing segment. */
int treeGone; /* Non-zero means the entire tree is
* being deleted, so everything must
* get cleaned up. */
{
ckfree((char*) segPtr);
return 0;
}
/*
*--------------------------------------------------------------
*
* CharCheckProc --
*
* This procedure is invoked to perform consistency checks
* on character segments.
*
* Results:
* None.
*
* Side effects:
* If the segment isn't inconsistent then the procedure
* panics.
*
*--------------------------------------------------------------
*/
/* ARGSUSED */
static void
CharCheckProc(segPtr, linePtr)
TkTextSegment *segPtr; /* Segment to check. */
TkTextLine *linePtr; /* Line containing segment. */
{
/*
* Make sure that the segment contains the number of
* characters indicated by its header, and that the last
* segment in a line ends in a newline. Also make sure
* that there aren't ever two character segments adjacent
* to each other: they should be merged together.
*/
if (segPtr->size <= 0) {
panic("CharCheckProc: segment has size <= 0");
}
if (strlen(segPtr->body.chars) != segPtr->size) {
panic("CharCheckProc: segment has wrong size");
}
if (segPtr->nextPtr == NULL) {
if (segPtr->body.chars[segPtr->size-1] != '\n') {
panic("CharCheckProc: line doesn't end with newline");
}
} else {
if (segPtr->nextPtr->typePtr == &tkTextCharType) {
panic("CharCheckProc: adjacent character segments weren't merged");
}
}
}
/*
*--------------------------------------------------------------
*
* ToggleDeleteProc --
*
* This procedure is invoked to delete toggle segments.
*
* Results:
* Returns 1 to indicate that the segment may not be deleted,
* unless the entire B-tree is going away.
*
* Side effects:
* If the tree is going away then the toggle's memory is
* freed; otherwise the toggle counts in nodes above the
* segment get updated.
*
*--------------------------------------------------------------
*/
static int
ToggleDeleteProc(segPtr, linePtr, treeGone)
TkTextSegment *segPtr; /* Segment to check. */
TkTextLine *linePtr; /* Line containing segment. */
int treeGone; /* Non-zero means the entire tree is
* being deleted, so everything must
* get cleaned up. */
{
if (treeGone) {
ckfree((char *) segPtr);
return 0;
}
/*
* This toggle is in the middle of a range of characters that's
* being deleted. Refuse to die. We'll be moved to the end of
* the deleted range and our cleanup procedure will be called
* later. Decrement node toggle counts here, and set a flag
* so we'll re-increment them in the cleanup procedure.
*/
if (segPtr->body.toggle.inNodeCounts) {
ChangeNodeToggleCount(linePtr->parentPtr,
segPtr->body.toggle.tagPtr, -1);
segPtr->body.toggle.inNodeCounts = 0;
}
return 1;
}
/*
*--------------------------------------------------------------
*
* ToggleCleanupProc --
*
* This procedure when a toggle is part of a line that's
* been modified in some way. It's invoked after the
* modifications are complete.
*
* Results:
* The return value is the head segment in a new list
* that is to replace the tail of the line that used to
* start at segPtr. This allows the procedure to delete
* or modify segPtr.
*
* Side effects:
* Toggle counts in the nodes above the new line will be
* updated if they're not already. Toggles may be collapsed
* if there are duplicate toggles at the same position.
*
*--------------------------------------------------------------
*/
static TkTextSegment *
ToggleCleanupProc(segPtr, linePtr)
TkTextSegment *segPtr; /* Segment to check. */
TkTextLine *linePtr; /* Line that now contains segment. */
{
TkTextSegment *segPtr2, *prevPtr;
int counts;
/*
* If this is a toggle-off segment, look ahead through the next
* segments to see if there's a toggle-on segment for the same tag
* before any segments with non-zero size. If so then the two
* toggles cancel each other; remove them both.
*/
if (segPtr->typePtr == &tkTextToggleOffType) {
for (prevPtr = segPtr, segPtr2 = prevPtr->nextPtr;
(segPtr2 != NULL) && (segPtr2->size == 0);
prevPtr = segPtr2, segPtr2 = prevPtr->nextPtr) {
if (segPtr2->typePtr != &tkTextToggleOnType) {
continue;
}
if (segPtr2->body.toggle.tagPtr != segPtr->body.toggle.tagPtr) {
continue;
}
counts = segPtr->body.toggle.inNodeCounts
+ segPtr2->body.toggle.inNodeCounts;
if (counts != 0) {
ChangeNodeToggleCount(linePtr->parentPtr,
segPtr->body.toggle.tagPtr, -counts);
}
prevPtr->nextPtr = segPtr2->nextPtr;
ckfree((char *) segPtr2);
segPtr2 = segPtr->nextPtr;
ckfree((char *) segPtr);
return segPtr2;
}
}
if (!segPtr->body.toggle.inNodeCounts) {
ChangeNodeToggleCount(linePtr->parentPtr,
segPtr->body.toggle.tagPtr, 1);
segPtr->body.toggle.inNodeCounts = 1;
}
return segPtr;
}
/*
*--------------------------------------------------------------
*
* ToggleLineChangeProc --
*
* This procedure is invoked when a toggle segment is about
* to move from one line to another.
*
* Results:
* None.
*
* Side effects:
* Toggle counts are decremented in the nodes above the line.
*
*--------------------------------------------------------------
*/
static void
ToggleLineChangeProc(segPtr, linePtr)
TkTextSegment *segPtr; /* Segment to check. */
TkTextLine *linePtr; /* Line that used to contain segment. */
{
if (segPtr->body.toggle.inNodeCounts) {
ChangeNodeToggleCount(linePtr->parentPtr,
segPtr->body.toggle.tagPtr, -1);
segPtr->body.toggle.inNodeCounts = 0;
}
}
/*
*--------------------------------------------------------------
*
* ToggleCheckProc --
*
* This procedure is invoked to perform consistency checks
* on toggle segments.
*
* Results:
* None.
*
* Side effects:
* If a consistency problem is found the procedure panics.
*
*--------------------------------------------------------------
*/
static void
ToggleCheckProc(segPtr, linePtr)
TkTextSegment *segPtr; /* Segment to check. */
TkTextLine *linePtr; /* Line containing segment. */
{
register Summary *summaryPtr;
if (segPtr->size != 0) {
panic("ToggleCheckProc: segment had non-zero size");
}
if (!segPtr->body.toggle.inNodeCounts) {
panic("ToggleCheckProc: toggle counts not updated in nodes");
}
for (summaryPtr = linePtr->parentPtr->summaryPtr; ;
summaryPtr = summaryPtr->nextPtr) {
if (summaryPtr == NULL) {
panic("ToggleCheckProc: tag not present in node");
}
if (summaryPtr->tagPtr == segPtr->body.toggle.tagPtr) {
break;
}
}
}
/*
*----------------------------------------------------------------------
*
* TkBTreeCharsInLine --
*
* This procedure returns a count of the number of characters
* in a given line.
*
* Results:
* The return value is the character count for linePtr.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
int
TkBTreeCharsInLine(linePtr)
TkTextLine *linePtr; /* Line whose characters should be
* counted. */
{
TkTextSegment *segPtr;
int count;
count = 0;
for (segPtr = linePtr->segPtr; segPtr != NULL; segPtr = segPtr->nextPtr) {
count += segPtr->size;
}
return count;
}