source: libcfa/src/containers/string_res.cfa@ 45c9441

ADT ast-experimental enum forall-pointer-decay pthread-emulation qualifiedEnum
Last change on this file since 45c9441 was 6cc87c0, checked in by Michael Brooks <mlbrooks@…>, 4 years ago

String bug fixes and new tests.

Enabled white-box visibility (DEBUG_ functions) into the string representation for heap-oriented tests.

string-gc/basicFillCompact

  • newly testable, now with the DEBUG_ visibility, but was basically already working

string-gc/fillCompact_withSharedEdits

  • new check for bug fixed here, where an append that triggers a compaction left substrings with dangling pointers

to the old text-pad range; fix is how string_res/assign now sequences growth-pushing operations before grabbing
pointers into the ranges of the old-version

string-overwrite

  • new broad check a few of whose cases are fixed here; fixes are the adjustments to the case priorities and

edge-case classifications in string_res/assign "adjust all substring string and handle locations" section

  • Property mode set to 100644
File size: 29.9 KB
RevLine 
[f450f2f]1//
2// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// string_res -- variable-length, mutable run of text, with resource semantics
8//
9// Author : Michael L. Brooks
10// Created On : Fri Sep 03 11:00:00 2021
11// Last Modified By : Michael L. Brooks
12// Last Modified On : Fri Sep 03 11:00:00 2021
13// Update Count : 1
14//
15
16#include "string_res.hfa"
17#include <stdlib.hfa> // e.g. malloc
18#include <string.h> // e.g. strlen
19
20//######################### VbyteHeap "header" #########################
21
22
[6cc87c0]23
24
25
26
27
28
29// DON'T COMMIT:
30// #define VbyteDebug
31
32
33
34
35
[f450f2f]36#ifdef VbyteDebug
[6cc87c0]37HandleNode *HeaderPtr;
[f450f2f]38#endif // VbyteDebug
39
40struct VbyteHeap {
41
42 int NoOfCompactions; // number of compactions of the byte area
43 int NoOfExtensions; // number of extensions in the size of the byte area
44 int NoOfReductions; // number of reductions in the size of the byte area
45
46 int InitSize; // initial number of bytes in the byte-string area
47 int CurrSize; // current number of bytes in the byte-string area
48 char *StartVbyte; // pointer to the `st byte of the start of the byte-string area
49 char *EndVbyte; // pointer to the next byte after the end of the currently used portion of byte-string area
50 void *ExtVbyte; // pointer to the next byte after the end of the byte-string area
51
52 HandleNode Header; // header node for handle list
53}; // VbyteHeap
54
55
56static inline void compaction( VbyteHeap & ); // compaction of the byte area
57static inline void garbage( VbyteHeap & ); // garbage collect the byte area
58static inline void extend( VbyteHeap &, int ); // extend the size of the byte area
59static inline void reduce( VbyteHeap &, int ); // reduce the size of the byte area
60
61static inline void ?{}( VbyteHeap &, int = 1000 );
62static inline void ^?{}( VbyteHeap & );
63static inline void ByteCopy( VbyteHeap &, char *, int, int, char *, int, int ); // copy a block of bytes from one location in the heap to another
64static inline int ByteCmp( VbyteHeap &, char *, int, int, char *, int, int ); // compare 2 blocks of bytes
65static inline char *VbyteAlloc( VbyteHeap &, int ); // allocate a block bytes in the heap
66
67
68static inline void AddThisAfter( HandleNode &, HandleNode & );
69static inline void DeleteNode( HandleNode & );
70static inline void MoveThisAfter( HandleNode &, const HandleNode & ); // move current handle after parameter handle
71
72
73// Allocate the storage for the variable sized area and intialize the heap variables.
74
75static inline void ?{}( VbyteHeap & this, int Size ) with(this) {
76#ifdef VbyteDebug
77 serr | "enter:VbyteHeap::VbyteHeap, this:" | &this | " Size:" | Size;
78#endif // VbyteDebug
79 NoOfCompactions = NoOfExtensions = NoOfReductions = 0;
80 InitSize = CurrSize = Size;
81 StartVbyte = EndVbyte = alloc(CurrSize);
82 ExtVbyte = (void *)( StartVbyte + CurrSize );
83 Header.flink = Header.blink = &Header;
84#ifdef VbyteDebug
85 HeaderPtr = &Header;
86 serr | "exit:VbyteHeap::VbyteHeap, this:" | &this;
87#endif // VbyteDebug
88} // VbyteHeap
89
90
91// Release the dynamically allocated storage for the byte area.
92
93static inline void ^?{}( VbyteHeap & this ) with(this) {
94 free( StartVbyte );
95} // ~VbyteHeap
96
97
98//######################### HandleNode #########################
99
100
101// Create a handle node. The handle is not linked into the handle list. This is the responsibilitiy of the handle
102// creator.
103
104void ?{}( HandleNode & this ) with(this) {
105#ifdef VbyteDebug
106 serr | "enter:HandleNode::HandleNode, this:" | &this;
107#endif // VbyteDebug
108 s = 0;
109 lnth = 0;
110#ifdef VbyteDebug
111 serr | "exit:HandleNode::HandleNode, this:" | &this;
112#endif // VbyteDebug
113} // HandleNode
114
115// Create a handle node. The handle is linked into the handle list at the end. This means that this handle will NOT be
116// in order by string address, but this is not a problem because a string with length zero does nothing during garbage
117// collection.
118
119void ?{}( HandleNode & this, VbyteHeap & vh ) with(this) {
120#ifdef VbyteDebug
121 serr | "enter:HandleNode::HandleNode, this:" | &this;
122#endif // VbyteDebug
123 s = 0;
124 lnth = 0;
125 AddThisAfter( this, *vh.Header.blink );
126#ifdef VbyteDebug
127 serr | "exit:HandleNode::HandleNode, this:" | &this;
128#endif // VbyteDebug
129} // HandleNode
130
131
132// Delete a node from the handle list by unchaining it from the list. If the handle node was allocated dynamically, it
133// is the responsibility of the creator to destroy it.
134
135void ^?{}( HandleNode & this ) with(this) {
136#ifdef VbyteDebug
137 serr | "enter:HandleNode::~HandleNode, this:" | & this;
138 {
139 serr | nlOff;
140 serr | " lnth:" | lnth | " s:" | (void *)s | ",\"";
141 for ( int i = 0; i < lnth; i += 1 ) {
142 serr | s[i];
143 } // for
144 serr | "\" flink:" | flink | " blink:" | blink | nl;
145 serr | nlOn;
146 }
147#endif // VbyteDebug
148 DeleteNode( this );
149} // ~HandleNode
150
151//######################### String Resource #########################
152
153
154VbyteHeap HeapArea;
155
[6cc87c0]156VbyteHeap * DEBUG_string_heap = & HeapArea;
157
158size_t DEBUG_string_bytes_avail_until_gc( VbyteHeap * heap ) {
159 return ((char*)heap->ExtVbyte) - heap->EndVbyte;
160}
161
162const char * DEBUG_string_heap_start( VbyteHeap * heap ) {
163 return heap->StartVbyte;
164}
165
166
[f450f2f]167// Returns the size of the string in bytes
168size_t size(const string_res &s) with(s) {
169 return Handle.lnth;
170}
171
172// Output operator
173ofstream & ?|?(ofstream &out, const string_res &s) {
174 // Store auto-newline state so it can be restored
175 bool anl = getANL$(out);
176 nlOff(out);
177 for (size_t i = 0; i < s.Handle.lnth; i++) {
178 out | s[i];
179 }
180 out | sep;
181 // Re-apply newlines after done, for chaining version
182 if (anl) nlOn(out);
183 return out;
184}
185
186void ?|?(ofstream &out, const string_res &s) {
187 // Store auto-newline state so it can be restored
188 bool anl = getANL$(out);
189 nlOff(out);
190 for (size_t i = 0; i < s.Handle.lnth; i++) {
191 // Need to re-apply on the last output operator, for whole-statement version
192 if (anl && i == s.Handle.lnth-1) nlOn(out);
193 out | s[i];
194 }
195 return out;
196}
197
198// Empty constructor
199void ?{}(string_res &s) with(s) {
200 (Handle){ HeapArea };
201 s.shareEditSet_prev = &s;
202 s.shareEditSet_next = &s;
203}
204
205// Constructor from a raw buffer and size
206void ?{}(string_res &s, const char* rhs, size_t rhslnth) with(s) {
207 (Handle){ HeapArea };
208 Handle.s = VbyteAlloc(HeapArea, rhslnth);
209 Handle.lnth = rhslnth;
210 for ( int i = 0; i < rhslnth; i += 1 ) { // copy characters
211 Handle.s[i] = rhs[i];
212 } // for
213 s.shareEditSet_prev = &s;
214 s.shareEditSet_next = &s;
215}
216
217// String literal constructor
218void ?{}(string_res &s, const char* rhs) {
219 (s){ rhs, strlen(rhs) };
220}
221
222// General copy constructor
223void ?{}(string_res &s, const string_res & s2, StrResInitMode mode, size_t start, size_t end ) {
224
225 (s.Handle){ HeapArea };
226 s.Handle.s = s2.Handle.s + start;
227 s.Handle.lnth = end - start;
228 MoveThisAfter(s.Handle, s2.Handle ); // insert this handle after rhs handle
229 // ^ bug? skip others at early point in string
230
231 if (mode == COPY_VALUE) {
232 // make s alone in its shareEditSet
233 s.shareEditSet_prev = &s;
234 s.shareEditSet_next = &s;
235 } else {
236 assert( mode == SHARE_EDITS );
237
238 // s2 is logically const but not implementation const
239 string_res & s2mod = (string_res &) s2;
240
241 // insert s after s2 on shareEditSet
242 s.shareEditSet_next = s2mod.shareEditSet_next;
243 s.shareEditSet_prev = &s2mod;
244 s.shareEditSet_next->shareEditSet_prev = &s;
245 s.shareEditSet_prev->shareEditSet_next = &s;
246 }
247}
248
[d8d512e]249void assign(string_res &this, const char* buffer, size_t bsize) {
[f450f2f]250
[6cc87c0]251 // traverse the incumbent share-edit set (SES) to recover the range of a base string to which `this` belongs
252 string_res * shareEditSetStartPeer = & this;
253 string_res * shareEditSetEndPeer = & this;
[f450f2f]254 for (string_res * editPeer = this.shareEditSet_next; editPeer != &this; editPeer = editPeer->shareEditSet_next) {
[6cc87c0]255 if ( editPeer->Handle.s < shareEditSetStartPeer->Handle.s ) {
256 shareEditSetStartPeer = editPeer;
257 }
258 if ( shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth < editPeer->Handle.s + editPeer->Handle.lnth) {
259 shareEditSetEndPeer = editPeer;
260 }
[f450f2f]261 }
262
[6cc87c0]263 // full string is from start of shareEditSetStartPeer thru end of shareEditSetEndPeer
264 // `this` occurs in the middle of it, to be replaced
265 // build up the new text in `pasting`
266
267 string_res pasting = {
268 shareEditSetStartPeer->Handle.s, // start of SES
269 this.Handle.s - shareEditSetStartPeer->Handle.s }; // length of SES, before this
270 append( pasting,
271 buffer, // start of replacement for this
272 bsize ); // length of replacement for this
273 append( pasting,
274 this.Handle.s + this.Handle.lnth, // start of SES after this
275 shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth -
276 (this.Handle.s + this.Handle.lnth) ); // length of SES, after this
277
278 // The above string building can trigger compaction.
279 // The reference points (that are arguments of the string building) may move during that building.
280 // From this point on, they are stable.
281 // So now, capture their values for use in the overlap cases, below.
282 // Do not factor these definitions with the arguments used above.
283
284 char * beforeBegin = shareEditSetStartPeer->Handle.s;
285 size_t beforeLen = this.Handle.s - beforeBegin;
[f450f2f]286
[6cc87c0]287 char * afterBegin = this.Handle.s + this.Handle.lnth;
288 size_t afterLen = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - afterBegin;
[f450f2f]289
290 size_t oldLnth = this.Handle.lnth;
291
292 this.Handle.s = pasting.Handle.s + beforeLen;
[d8d512e]293 this.Handle.lnth = bsize;
[f450f2f]294 MoveThisAfter( this.Handle, pasting.Handle );
295
296 // adjust all substring string and handle locations, and check if any substring strings are outside the new base string
297 char *limit = pasting.Handle.s + pasting.Handle.lnth;
298 for (string_res * p = this.shareEditSet_next; p != &this; p = p->shareEditSet_next) {
299 assert (p->Handle.s >= beforeBegin);
[6cc87c0]300 if ( p->Handle.s >= afterBegin ) {
301 assert ( p->Handle.s <= afterBegin + afterLen );
302 assert ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen );
303 // p starts after the edit
304 // take start and end as end-anchored
305 size_t startOffsetFromEnd = afterBegin + afterLen - p->Handle.s;
306 p->Handle.s = limit - startOffsetFromEnd;
307 // p->Handle.lnth unaffected
308 } else if ( p->Handle.s <= beforeBegin + beforeLen ) {
309 // p starts before, or at the start of, the edit
310 if ( p->Handle.s + p->Handle.lnth <= beforeBegin + beforeLen ) {
[f450f2f]311 // p ends before the edit
312 // take end as start-anchored too
313 // p->Handle.lnth unaffected
314 } else if ( p->Handle.s + p->Handle.lnth < afterBegin ) {
[6cc87c0]315 // p ends during the edit; p does not include the last character replaced
[f450f2f]316 // clip end of p to end at start of edit
317 p->Handle.lnth = beforeLen - ( p->Handle.s - beforeBegin );
318 } else {
319 // p ends after the edit
320 assert ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen );
321 // take end as end-anchored
322 // stretch-shrink p according to the edit
323 p->Handle.lnth += this.Handle.lnth;
324 p->Handle.lnth -= oldLnth;
325 }
326 // take start as start-anchored
327 size_t startOffsetFromStart = p->Handle.s - beforeBegin;
328 p->Handle.s = pasting.Handle.s + startOffsetFromStart;
[6cc87c0]329 } else {
330 assert ( p->Handle.s < afterBegin );
[f450f2f]331 // p starts during the edit
332 assert( p->Handle.s + p->Handle.lnth >= beforeBegin + beforeLen );
333 if ( p->Handle.s + p->Handle.lnth < afterBegin ) {
[6cc87c0]334 // p ends during the edit; p does not include the last character replaced
[f450f2f]335 // set p to empty string at start of edit
336 p->Handle.s = this.Handle.s;
337 p->Handle.lnth = 0;
338 } else {
[6cc87c0]339 // p includes the end of the edit
[f450f2f]340 // clip start of p to start at end of edit
[6cc87c0]341 int charsToClip = afterBegin - p->Handle.s;
[f450f2f]342 p->Handle.s = this.Handle.s + this.Handle.lnth;
[6cc87c0]343 p->Handle.lnth -= charsToClip;
[f450f2f]344 }
345 }
346 MoveThisAfter( p->Handle, pasting.Handle ); // move substring handle to maintain sorted order by string position
347 }
348}
349
[d8d512e]350void ?=?(string_res &s, const char* other) {
351 assign(s, other, strlen(other));
352}
353
354void ?=?(string_res &s, char other) {
355 assign(s, &other, 1);
356}
357
358// Copy assignment operator
359void ?=?(string_res & this, const string_res & rhs) with( this ) {
360 assign(this, rhs.Handle.s, rhs.Handle.lnth);
361}
362
[f450f2f]363void ?=?(string_res & this, string_res & rhs) with( this ) {
364 const string_res & rhs2 = rhs;
365 this = rhs2;
366}
367
368
369// Destructor
370void ^?{}(string_res &s) with(s) {
371 // much delegated to implied ^VbyteSM
372
373 // sever s from its share-edit peers, if any (four no-ops when already solo)
374 s.shareEditSet_prev->shareEditSet_next = s.shareEditSet_next;
375 s.shareEditSet_next->shareEditSet_prev = s.shareEditSet_prev;
376 s.shareEditSet_next = &s;
377 s.shareEditSet_prev = &s;
378}
379
380
381// Returns the character at the given index
382// With unicode support, this may be different from just the byte at the given
383// offset from the start of the string.
384char ?[?](const string_res &s, size_t index) with(s) {
385 //TODO: Check if index is valid (no exceptions yet)
386 return Handle.s[index];
387}
388
[d8d512e]389
[f450f2f]390///////////////////////////////////////////////////////////////////
[d8d512e]391// Concatenation
[f450f2f]392
[d8d512e]393void append(string_res &str1, const char * buffer, size_t bsize) {
394 size_t clnth = size(str1) + bsize;
395 if ( str1.Handle.s + size(str1) == buffer ) { // already juxtapose ?
396 // no-op
[f450f2f]397 } else { // must copy some text
398 if ( str1.Handle.s + size(str1) == VbyteAlloc(HeapArea, 0) ) { // str1 at end of string area ?
[d8d512e]399 VbyteAlloc(HeapArea, bsize); // create room for 2nd part at the end of string area
[f450f2f]400 } else { // copy the two parts
401 char * str1oldBuf = str1.Handle.s;
402 str1.Handle.s = VbyteAlloc( HeapArea, clnth );
403 ByteCopy( HeapArea, str1.Handle.s, 0, str1.Handle.lnth, str1oldBuf, 0, str1.Handle.lnth);
404 } // if
[d8d512e]405 ByteCopy( HeapArea, str1.Handle.s, str1.Handle.lnth, bsize, (char*)buffer, 0, (int)bsize);
[f450f2f]406 // VbyteHeap & this, char *Dst, int DstStart, int DstLnth, char *Src, int SrcStart, int SrcLnth
407 } // if
408 str1.Handle.lnth = clnth;
409}
410
411void ?+=?(string_res &str1, const string_res &str2) {
[d8d512e]412 append( str1, str2.Handle.s, str2.Handle.lnth );
[f450f2f]413}
414
415void ?+=?(string_res &s, char other) {
[d8d512e]416 append( s, &other, 1 );
[f450f2f]417}
418
419void ?+=?(string_res &s, const char* other) {
[d8d512e]420 append( s, other, strlen(other) );
[f450f2f]421}
422
423
424
425
426//////////////////////////////////////////////////////////
427// Comparisons
428
429
430bool ?==?(const string_res &s1, const string_res &s2) {
431 return ByteCmp( HeapArea, s1.Handle.s, 0, s1.Handle.lnth, s2.Handle.s, 0, s2.Handle.lnth) == 0;
432}
433
434bool ?!=?(const string_res &s1, const string_res &s2) {
435 return !(s1 == s2);
436}
437bool ?==?(const string_res &s, const char* other) {
438 string_res sother = other;
439 return s == sother;
440}
441bool ?!=?(const string_res &s, const char* other) {
442 return !(s == other);
443}
444
445
446//////////////////////////////////////////////////////////
447// Search
448
449bool contains(const string_res &s, char ch) {
450 for (i; size(s)) {
451 if (s[i] == ch) return true;
452 }
453 return false;
454}
455
456int find(const string_res &s, char search) {
457 for (i; size(s)) {
458 if (s[i] == search) return i;
459 }
460 return size(s);
461}
462
463 /* Remaining implementations essentially ported from Sunjay's work */
464
465int find(const string_res &s, const string_res &search) {
466 return find(s, search.Handle.s, search.Handle.lnth);
467}
468
469int find(const string_res &s, const char* search) {
470 return find(s, search, strlen(search));
471}
472
473int find(const string_res &s, const char* search, size_t searchsize) {
474 // FIXME: This is a naive algorithm. We probably want to switch to someting
475 // like Boyer-Moore in the future.
476 // https://en.wikipedia.org/wiki/String_searching_algorithm
477
478 // Always find the empty string
479 if (searchsize == 0) {
480 return 0;
481 }
482
483 for (size_t i = 0; i < s.Handle.lnth; i++) {
484 size_t remaining = s.Handle.lnth - i;
485 // Never going to find the search string if the remaining string is
486 // smaller than search
487 if (remaining < searchsize) {
488 break;
489 }
490
491 bool matched = true;
492 for (size_t j = 0; j < searchsize; j++) {
493 if (search[j] != s.Handle.s[i + j]) {
494 matched = false;
495 break;
496 }
497 }
498 if (matched) {
499 return i;
500 }
501 }
502
503 return s.Handle.lnth;
504}
505
506bool includes(const string_res &s, const string_res &search) {
507 return includes(s, search.Handle.s, search.Handle.lnth);
508}
509
510bool includes(const string_res &s, const char* search) {
511 return includes(s, search, strlen(search));
512}
513
514bool includes(const string_res &s, const char* search, size_t searchsize) {
515 return find(s, search, searchsize) < s.Handle.lnth;
516}
517
518bool startsWith(const string_res &s, const string_res &prefix) {
519 return startsWith(s, prefix.Handle.s, prefix.Handle.lnth);
520}
521
522bool startsWith(const string_res &s, const char* prefix) {
523 return startsWith(s, prefix, strlen(prefix));
524}
525
526bool startsWith(const string_res &s, const char* prefix, size_t prefixsize) {
527 if (s.Handle.lnth < prefixsize) {
528 return false;
529 }
530 return memcmp(s.Handle.s, prefix, prefixsize) == 0;
531}
532
533bool endsWith(const string_res &s, const string_res &suffix) {
534 return endsWith(s, suffix.Handle.s, suffix.Handle.lnth);
535}
536
537bool endsWith(const string_res &s, const char* suffix) {
538 return endsWith(s, suffix, strlen(suffix));
539}
540
541bool endsWith(const string_res &s, const char* suffix, size_t suffixsize) {
542 if (s.Handle.lnth < suffixsize) {
543 return false;
544 }
545 // Amount to offset the bytes pointer so that we are comparing the end of s
546 // to suffix. s.bytes + offset should be the first byte to compare against suffix
547 size_t offset = s.Handle.lnth - suffixsize;
548 return memcmp(s.Handle.s + offset, suffix, suffixsize) == 0;
549}
550
551 /* Back to Mike's work */
552
553
554///////////////////////////////////////////////////////////////////////////
555// charclass, include, exclude
556
557void ?{}( charclass_res & this, const string_res & chars) {
558 (this){ chars.Handle.s, chars.Handle.lnth };
559}
560
561void ?{}( charclass_res & this, const char * chars ) {
562 (this){ chars, strlen(chars) };
563}
564
565void ?{}( charclass_res & this, const char * chars, size_t charssize ) {
566 (this.chars){ chars, charssize };
567 // now sort it ?
568}
569
570void ^?{}( charclass_res & this ) {
571 ^(this.chars){};
572}
573
574static bool test( const charclass_res & mask, char c ) {
575 // instead, use sorted char list?
576 return contains( mask.chars, c );
577}
578
579int exclude(const string_res &s, const charclass_res &mask) {
580 for (int i = 0; i < size(s); i++) {
581 if ( test(mask, s[i]) ) return i;
582 }
583 return size(s);
584}
585
586int include(const string_res &s, const charclass_res &mask) {
587 for (int i = 0; i < size(s); i++) {
588 if ( ! test(mask, s[i]) ) return i;
589 }
590 return size(s);
591}
592
593//######################### VbyteHeap "implementation" #########################
594
595
596// Add a new HandleNode node n after the current HandleNode node.
597
598static inline void AddThisAfter( HandleNode & this, HandleNode & n ) with(this) {
599#ifdef VbyteDebug
600 serr | "enter:AddThisAfter, this:" | &this | " n:" | &n;
601#endif // VbyteDebug
602 flink = n.flink;
603 blink = &n;
604 n.flink->blink = &this;
605 n.flink = &this;
606#ifdef VbyteDebug
607 {
608 serr | "HandleList:";
609 serr | nlOff;
610 for ( HandleNode *ni = HeaderPtr->flink; ni != HeaderPtr; ni = ni->flink ) {
611 serr | "\tnode:" | ni | " lnth:" | ni->lnth | " s:" | (void *)ni->s | ",\"";
612 for ( int i = 0; i < ni->lnth; i += 1 ) {
613 serr | ni->s[i];
614 } // for
615 serr | "\" flink:" | ni->flink | " blink:" | ni->blink | nl;
616 } // for
617 serr | nlOn;
618 }
619 serr | "exit:AddThisAfter";
620#endif // VbyteDebug
621} // AddThisAfter
622
623
624// Delete the current HandleNode node.
625
626static inline void DeleteNode( HandleNode & this ) with(this) {
627#ifdef VbyteDebug
628 serr | "enter:DeleteNode, this:" | &this;
629#endif // VbyteDebug
630 flink->blink = blink;
631 blink->flink = flink;
632#ifdef VbyteDebug
633 serr | "exit:DeleteNode";
634#endif // VbyteDebug
635} // DeleteNode
636
637
638
639// Allocates specified storage for a string from byte-string area. If not enough space remains to perform the
640// allocation, the garbage collection routine is called and a second attempt is made to allocate the space. If the
641// second attempt fails, a further attempt is made to create a new, larger byte-string area.
642
643static inline char * VbyteAlloc( VbyteHeap & this, int size ) with(this) {
644#ifdef VbyteDebug
645 serr | "enter:VbyteAlloc, size:" | size;
646#endif // VbyteDebug
647 uintptr_t NoBytes;
648 char *r;
649
650 NoBytes = ( uintptr_t )EndVbyte + size;
651 if ( NoBytes > ( uintptr_t )ExtVbyte ) { // enough room for new byte-string ?
652 garbage( this ); // firer up the garbage collector
653 NoBytes = ( uintptr_t )EndVbyte + size; // try again
654 if ( NoBytes > ( uintptr_t )ExtVbyte ) { // enough room for new byte-string ?
655assert( 0 && "need to implement actual growth" );
656 // extend( size ); // extend the byte-string area
657 } // if
658 } // if
659 r = EndVbyte;
660 EndVbyte += size;
661#ifdef VbyteDebug
662 serr | "exit:VbyteAlloc, r:" | (void *)r | " EndVbyte:" | (void *)EndVbyte | " ExtVbyte:" | ExtVbyte;
663#endif // VbyteDebug
664 return r;
665} // VbyteAlloc
666
667
668// Move an existing HandleNode node h somewhere after the current HandleNode node so that it is in ascending order by
669// the address in the byte string area.
670
671static inline void MoveThisAfter( HandleNode & this, const HandleNode & h ) with(this) {
672#ifdef VbyteDebug
673 serr | "enter:MoveThisAfter, this:" | & this | " h:" | & h;
674#endif // VbyteDebug
675 if ( s < h.s ) { // check argument values
676 // serr | "VbyteSM: Error - Cannot move byte string starting at:" | s | " after byte string starting at:"
677 // | ( h->s ) | " and keep handles in ascending order";
678 // exit(-1 );
679 assert( 0 && "VbyteSM: Error - Cannot move byte strings as requested and keep handles in ascending order");
680 } // if
681
682 HandleNode *i;
683 for ( i = h.flink; i->s != 0 && s > ( i->s ); i = i->flink ); // find the position for this node after h
684 if ( & this != i->blink ) {
685 DeleteNode( this );
686 AddThisAfter( this, *i->blink );
687 } // if
688#ifdef VbyteDebug
689 {
690 serr | "HandleList:";
691 serr | nlOff;
692 for ( HandleNode *n = HeaderPtr->flink; n != HeaderPtr; n = n->flink ) {
693 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
694 for ( int i = 0; i < n->lnth; i += 1 ) {
695 serr | n->s[i];
696 } // for
[6cc87c0]697 serr | "\" flink:" | n->flink | " blink:" | n->blink | nl;
[f450f2f]698 } // for
699 serr | nlOn;
700 }
[6cc87c0]701 serr | "exit:MoveThisAfter";
[f450f2f]702#endif // VbyteDebug
703} // MoveThisAfter
704
705
706
707
708
709//######################### VbyteHeap #########################
710
711// Move characters from one location in the byte-string area to another. The routine handles the following situations:
712//
713// if the |Src| > |Dst| => truncate
714// if the |Dst| > |Src| => pad Dst with blanks
715
716void ByteCopy( VbyteHeap & this, char *Dst, int DstStart, int DstLnth, char *Src, int SrcStart, int SrcLnth ) {
717 for ( int i = 0; i < DstLnth; i += 1 ) {
718 if ( i == SrcLnth ) { // |Dst| > |Src|
719 for ( ; i < DstLnth; i += 1 ) { // pad Dst with blanks
720 Dst[DstStart + i] = ' ';
721 } // for
722 break;
723 } // exit
724 Dst[DstStart + i] = Src[SrcStart + i];
725 } // for
726} // ByteCopy
727
728// Compare two byte strings in the byte-string area. The routine returns the following values:
729//
730// 1 => Src1-byte-string > Src2-byte-string
731// 0 => Src1-byte-string = Src2-byte-string
732// -1 => Src1-byte-string < Src2-byte-string
733
734int ByteCmp( VbyteHeap & this, char *Src1, int Src1Start, int Src1Lnth, char *Src2, int Src2Start, int Src2Lnth ) with(this) {
735#ifdef VbyteDebug
736 serr | "enter:ByteCmp, Src1Start:" | Src1Start | " Src1Lnth:" | Src1Lnth | " Src2Start:" | Src2Start | " Src2Lnth:" | Src2Lnth;
737#endif // VbyteDebug
738 int cmp;
739
740 CharZip: for ( int i = 0; ; i += 1 ) {
741 if ( i == Src2Lnth - 1 ) {
742 for ( ; ; i += 1 ) {
743 if ( i == Src1Lnth - 1 ) {
744 cmp = 0;
745 break CharZip;
746 } // exit
747 if ( Src1[Src1Start + i] != ' ') {
748 // SUSPECTED BUG: this could be be why Peter got the bug report about == " " (why is this case here at all?)
749 cmp = 1;
750 break CharZip;
751 } // exit
752 } // for
753 } // exit
754 if ( i == Src1Lnth - 1 ) {
755 for ( ; ; i += 1 ) {
756 if ( i == Src2Lnth - 1 ) {
757 cmp = 0;
758 break CharZip;
759 } // exit
760 if ( Src2[Src2Start + i] != ' ') {
761 cmp = -1;
762 break CharZip;
763 } // exit
764 } // for
765 } // exit
766 if ( Src2[Src2Start + i] != Src1[Src1Start+ i]) {
767 cmp = Src1[Src1Start + i] > Src2[Src2Start + i] ? 1 : -1;
768 break CharZip;
769 } // exit
770 } // for
771#ifdef VbyteDebug
772 serr | "exit:ByteCmp, cmp:" | cmp;
773#endif // VbyteDebug
774 return cmp;
775} // ByteCmp
776
777
778// The compaction moves all of the byte strings currently in use to the beginning of the byte-string area and modifies
779// the handles to reflect the new positions of the byte strings. Compaction assumes that the handle list is in ascending
780// order by pointers into the byte-string area. The strings associated with substrings do not have to be moved because
781// the containing string has been moved. Hence, they only require that their string pointers be adjusted.
782
783void compaction(VbyteHeap & this) with(this) {
784 HandleNode *h;
785 char *obase, *nbase, *limit;
786
787 NoOfCompactions += 1;
788 EndVbyte = StartVbyte;
789 h = Header.flink; // ignore header node
790 for (;;) {
791 ByteCopy( this, EndVbyte, 0, h->lnth, h->s, 0, h->lnth );
792 obase = h->s;
793 h->s = EndVbyte;
794 nbase = h->s;
795 EndVbyte += h->lnth;
796 limit = obase + h->lnth;
797 h = h->flink;
798
799 // check if any substrings are allocated within a string
800
801 for (;;) {
802 if ( h == &Header ) break; // end of header list ?
803 if ( h->s >= limit ) break; // outside of current string ?
804 h->s = nbase + (( uintptr_t )h->s - ( uintptr_t )obase );
805 h = h->flink;
806 } // for
807 if ( h == &Header ) break; // end of header list ?
808 } // for
809} // compaction
810
811
812// Garbage determines the amount of free space left in the heap and then reduces, leave the same, or extends the size of
813// the heap. The heap is then compacted in the existing heap or into the newly allocated heap.
814
815void garbage(VbyteHeap & this ) with(this) {
816#ifdef VbyteDebug
817 serr | "enter:garbage";
818 {
819 serr | "HandleList:";
820 for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) {
821 serr | nlOff;
822 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
823 for ( int i = 0; i < n->lnth; i += 1 ) {
824 serr | n->s[i];
825 } // for
826 serr | nlOn;
827 serr | "\" flink:" | n->flink | " blink:" | n->blink;
828 } // for
829 }
830#endif // VbyteDebug
831 int AmountUsed, AmountFree;
832
833 AmountUsed = 0;
834 for ( HandleNode *i = Header.flink; i != &Header; i = i->flink ) { // calculate amount of byte area used
835 AmountUsed += i->lnth;
836 } // for
837 AmountFree = ( uintptr_t )ExtVbyte - ( uintptr_t )StartVbyte - AmountUsed;
838
839 if ( AmountFree < ( int )( CurrSize * 0.1 )) { // free space less than 10% ?
840
841assert( 0 && "need to implement actual growth" );
842// extend( CurrSize ); // extend the heap
843
844 // Peter says, "This needs work before it should be used."
845 // } else if ( AmountFree > CurrSize / 2 ) { // free space greater than 3 times the initial allocation ?
846 // reduce(( AmountFree / CurrSize - 3 ) * CurrSize ); // reduce the memory
847
848 } // if
849 compaction(this); // compact the byte area, in the same or new heap area
850#ifdef VbyteDebug
851 {
852 serr | "HandleList:";
853 for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) {
854 serr | nlOff;
855 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
856 for ( int i = 0; i < n->lnth; i += 1 ) {
857 serr | n->s[i];
858 } // for
859 serr | nlOn;
860 serr | "\" flink:" | n->flink | " blink:" | n->blink;
861 } // for
862 }
863 serr | "exit:garbage";
864#endif // VbyteDebug
865} // garbage
866
867#undef VbyteDebug
868
869//WIP
870#if 0
871
872
873// Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string
874// area is deleted.
875
876void VbyteHeap::extend( int size ) {
877#ifdef VbyteDebug
878 serr | "enter:extend, size:" | size;
879#endif // VbyteDebug
880 char *OldStartVbyte;
881
882 NoOfExtensions += 1;
883 OldStartVbyte = StartVbyte; // save previous byte area
884
885 CurrSize += size > InitSize ? size : InitSize; // minimum extension, initial size
886 StartVbyte = EndVbyte = new char[CurrSize];
887 ExtVbyte = (void *)( StartVbyte + CurrSize );
888 compaction(); // copy from old heap to new & adjust pointers to new heap
889 delete OldStartVbyte; // release old heap
890#ifdef VbyteDebug
891 serr | "exit:extend, CurrSize:" | CurrSize;
892#endif // VbyteDebug
893} // extend
894
895
896// Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string
897// area is deleted.
898
899void VbyteHeap::reduce( int size ) {
900#ifdef VbyteDebug
901 serr | "enter:reduce, size:" | size;
902#endif // VbyteDebug
903 char *OldStartVbyte;
904
905 NoOfReductions += 1;
906 OldStartVbyte = StartVbyte; // save previous byte area
907
908 CurrSize -= size;
909 StartVbyte = EndVbyte = new char[CurrSize];
910 ExtVbyte = (void *)( StartVbyte + CurrSize );
911 compaction(); // copy from old heap to new & adjust pointers to new heap
912 delete OldStartVbyte; // release old heap
913#ifdef VbyteDebug
914 serr | "exit:reduce, CurrSize:" | CurrSize;
915#endif // VbyteDebug
916} // reduce
917
918
919#endif
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