source: libcfa/src/containers/string_res.cfa@ d9b7b66

Last change on this file since d9b7b66 was 7d25f44, checked in by Peter A. Buhr <pabuhr@…>, 2 years ago

update files from old separator manipulator names to new names
  • Property mode set to 100644
File size: 38.3 KB
Line 
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 : Peter A. Buhr
12// Last Modified On : Thu Jun 29 09:29:06 2023
13// Update Count : 2
14//
15
16#include "string_res.hfa"
17#include "string_sharectx.hfa"
18#include "stdlib.hfa"
19
20// Workaround for observed performance penalty from calling CFA's alloc.
21// Workaround is: EndVbyte = TEMP_ALLOC(char, CurrSize)
22// Should be: EndVbyte = alloc(CurrSize)
23#define TEMP_ALLOC(T, n) (( T* ) malloc( n * sizeof( T ) ))
24
25#include <assert.h>
26
27//######################### VbyteHeap "header" #########################
28
29#ifdef VbyteDebug
30HandleNode *HeaderPtr;
31#endif // VbyteDebug
32
33struct VbyteHeap {
34
35 int NoOfCompactions; // number of compactions of the byte area
36 int NoOfExtensions; // number of extensions in the size of the byte area
37 int NoOfReductions; // number of reductions in the size of the byte area
38
39 int InitSize; // initial number of bytes in the byte-string area
40 int CurrSize; // current number of bytes in the byte-string area
41 char *StartVbyte; // pointer to the `st byte of the start of the byte-string area
42 char *EndVbyte; // pointer to the next byte after the end of the currently used portion of byte-string area
43 void *ExtVbyte; // pointer to the next byte after the end of the byte-string area
44
45 HandleNode Header; // header node for handle list
46}; // VbyteHeap
47
48
49static void compaction( VbyteHeap & ); // compaction of the byte area
50static void garbage( VbyteHeap &, int ); // garbage collect the byte area
51static void extend( VbyteHeap &, int ); // extend the size of the byte area
52static void reduce( VbyteHeap &, int ); // reduce the size of the byte area
53
54static void ?{}( VbyteHeap &, size_t = 1000 );
55static void ^?{}( VbyteHeap & );
56
57static int ByteCmp( char *, int, int, char *, int, int ); // compare 2 blocks of bytes
58static char *VbyteAlloc( VbyteHeap &, int ); // allocate a block bytes in the heap
59static char *VbyteTryAdjustLast( VbyteHeap &, int );
60
61static void AddThisAfter( HandleNode &, HandleNode & );
62static void DeleteNode( HandleNode & );
63static void MoveThisAfter( HandleNode &, const HandleNode & ); // move current handle after parameter handle
64
65
66// Allocate the storage for the variable sized area and intialize the heap variables.
67
68static void ?{}( VbyteHeap & this, size_t Size ) with(this) {
69#ifdef VbyteDebug
70 serr | "enter:VbyteHeap::VbyteHeap, this:" | &this | " Size:" | Size;
71#endif // VbyteDebug
72 NoOfCompactions = NoOfExtensions = NoOfReductions = 0;
73 InitSize = CurrSize = Size;
74 StartVbyte = EndVbyte = TEMP_ALLOC(char, CurrSize);
75 ExtVbyte = (void *)( StartVbyte + CurrSize );
76 Header.flink = Header.blink = &Header;
77 Header.ulink = & this;
78#ifdef VbyteDebug
79 HeaderPtr = &Header;
80 serr | "exit:VbyteHeap::VbyteHeap, this:" | &this;
81#endif // VbyteDebug
82} // VbyteHeap
83
84
85// Release the dynamically allocated storage for the byte area.
86
87static void ^?{}( VbyteHeap & this ) with(this) {
88 free( StartVbyte );
89} // ~VbyteHeap
90
91
92//######################### HandleNode #########################
93
94
95// Create a handle node. The handle is not linked into the handle list. This is the responsibilitiy of the handle
96// creator.
97
98static void ?{}( HandleNode & this ) with(this) {
99#ifdef VbyteDebug
100 serr | "enter:HandleNode::HandleNode, this:" | &this;
101#endif // VbyteDebug
102 s = 0;
103 lnth = 0;
104#ifdef VbyteDebug
105 serr | "exit:HandleNode::HandleNode, this:" | &this;
106#endif // VbyteDebug
107} // HandleNode
108
109// Create a handle node. The handle is linked into the handle list at the end. This means that this handle will NOT be
110// in order by string address, but this is not a problem because a string with length zero does nothing during garbage
111// collection.
112
113static void ?{}( HandleNode & this, VbyteHeap & vh ) with(this) {
114#ifdef VbyteDebug
115 serr | "enter:HandleNode::HandleNode, this:" | &this;
116#endif // VbyteDebug
117 s = 0;
118 lnth = 0;
119 ulink = &vh;
120 AddThisAfter( this, *vh.Header.blink );
121#ifdef VbyteDebug
122 serr | "exit:HandleNode::HandleNode, this:" | &this;
123#endif // VbyteDebug
124} // HandleNode
125
126
127// Delete a node from the handle list by unchaining it from the list. If the handle node was allocated dynamically, it
128// is the responsibility of the creator to destroy it.
129
130static void ^?{}( HandleNode & this ) with(this) {
131#ifdef VbyteDebug
132 serr | "enter:HandleNode::~HandleNode, this:" | & this;
133 {
134 serr | nlOff;
135 serr | " lnth:" | lnth | " s:" | (void *)s | ",\"";
136 for ( int i = 0; i < lnth; i += 1 ) {
137 serr | s[i];
138 } // for
139 serr | "\" flink:" | flink | " blink:" | blink | nl;
140 serr | nlOn;
141 }
142#endif // VbyteDebug
143 DeleteNode( this );
144} // ~HandleNode
145
146
147//######################### String Sharing Context #########################
148
149static string_sharectx * ambient_string_sharectx; // fickle top of stack
150static string_sharectx default_string_sharectx = {NEW_SHARING}; // stable bottom of stack
151
152void ?{}( string_sharectx & this, StringSharectx_Mode mode ) with( this ) {
153 (older){ ambient_string_sharectx };
154 if ( mode == NEW_SHARING ) {
155 (activeHeap){ new( (size_t) 1000 ) };
156 } else {
157 verify( mode == NO_SHARING );
158 (activeHeap){ 0p };
159 }
160 ambient_string_sharectx = & this;
161}
162
163void ^?{}( string_sharectx & this ) with( this ) {
164 if ( activeHeap ) delete( activeHeap );
165
166 // unlink this from older-list starting from ambient_string_sharectx
167 // usually, this==ambient_string_sharectx and the loop runs zero times
168 string_sharectx *& c = ambient_string_sharectx;
169 while ( c != &this ) &c = &c->older; // find this
170 c = this.older; // unlink
171}
172
173//######################### String Resource #########################
174
175
176VbyteHeap * DEBUG_string_heap() {
177 assert( ambient_string_sharectx->activeHeap && "No sharing context is active" );
178 return ambient_string_sharectx->activeHeap;
179}
180
181size_t DEBUG_string_bytes_avail_until_gc( VbyteHeap * heap ) {
182 return ((char*)heap->ExtVbyte) - heap->EndVbyte;
183}
184
185size_t DEBUG_string_bytes_in_heap( VbyteHeap * heap ) {
186 return heap->CurrSize;
187}
188
189const char * DEBUG_string_heap_start( VbyteHeap * heap ) {
190 return heap->StartVbyte;
191}
192
193// Returns the size of the string in bytes
194size_t size(const string_res &s) with(s) {
195 return Handle.lnth;
196}
197
198// Output operator
199ofstream & ?|?(ofstream &out, const string_res &s) {
200 // Store auto-newline state so it can be restored
201 bool anl = getANL$(out);
202 nlOff(out);
203 for (size_t i = 0; i < s.Handle.lnth; i++) {
204 out | s[i];
205 }
206 out | sepVal;
207 // Re-apply newlines after done, for chaining version
208 if (anl) nlOn(out);
209 return out;
210}
211
212void ?|?(ofstream &out, const string_res &s) {
213 // Store auto-newline state so it can be restored
214 bool anl = getANL$(out);
215 if( s.Handle.lnth == 0 ) {
216 sout | "";
217 } else {
218 nlOff(out);
219 for (size_t i = 0; i < s.Handle.lnth; i++) {
220 // Need to re-apply on the last output operator, for whole-statement version
221 if (anl && i == s.Handle.lnth-1) nlOn(out);
222 out | s[i];
223 }
224 }
225}
226
227// Empty constructor
228void ?{}(string_res &s) with(s) {
229 if( ambient_string_sharectx->activeHeap ) {
230 (Handle){ * ambient_string_sharectx->activeHeap };
231 (shareEditSet_owns_ulink){ false };
232 verify( Handle.s == 0p && Handle.lnth == 0 );
233 } else {
234 (Handle){ * new( (size_t) 10 ) }; // TODO: can I lazily avoid allocating for empty string
235 (shareEditSet_owns_ulink){ true };
236 Handle.s = Handle.ulink->StartVbyte;
237 verify( Handle.lnth == 0 );
238 }
239 s.shareEditSet_prev = &s;
240 s.shareEditSet_next = &s;
241}
242
243static void eagerCopyCtorHelper(string_res &s, const char* rhs, size_t rhslnth) with(s) {
244 if( ambient_string_sharectx->activeHeap ) {
245 (Handle){ * ambient_string_sharectx->activeHeap };
246 (shareEditSet_owns_ulink){ false };
247 } else {
248 (Handle){ * new( rhslnth ) };
249 (shareEditSet_owns_ulink){ true };
250 }
251 Handle.s = VbyteAlloc(*Handle.ulink, rhslnth);
252 Handle.lnth = rhslnth;
253 memmove( Handle.s, rhs, rhslnth );
254 s.shareEditSet_prev = &s;
255 s.shareEditSet_next = &s;
256}
257
258// Constructor from a raw buffer and size
259void ?{}(string_res &s, const char* rhs, size_t rhslnth) with(s) {
260 eagerCopyCtorHelper(s, rhs, rhslnth);
261}
262
263// private ctor (not in header): use specified heap (ignore ambient) and copy chars in
264void ?{}( string_res &s, VbyteHeap & heap, const char* rhs, size_t rhslnth ) with(s) {
265 (Handle){ heap };
266 Handle.s = VbyteAlloc(*Handle.ulink, rhslnth);
267 Handle.lnth = rhslnth;
268 (s.shareEditSet_owns_ulink){ false };
269 memmove( Handle.s, rhs, rhslnth );
270 s.shareEditSet_prev = &s;
271 s.shareEditSet_next = &s;
272}
273
274// General copy constructor
275void ?{}(string_res &s, const string_res & s2, StrResInitMode mode, size_t start, size_t end ) {
276
277 verify( start <= end && end <= s2.Handle.lnth );
278
279 if (s2.Handle.ulink != ambient_string_sharectx->activeHeap && mode == COPY_VALUE) {
280 // crossing heaps (including private): copy eagerly
281 eagerCopyCtorHelper(s, s2.Handle.s + start, end - start);
282 verify(s.shareEditSet_prev == &s);
283 verify(s.shareEditSet_next == &s);
284 } else {
285 (s.Handle){};
286 s.Handle.s = s2.Handle.s + start;
287 s.Handle.lnth = end - start;
288 s.Handle.ulink = s2.Handle.ulink;
289
290 AddThisAfter(s.Handle, s2.Handle ); // insert this handle after rhs handle
291 // ^ bug? skip others at early point in string
292
293 if (mode == COPY_VALUE) {
294 verify(s2.Handle.ulink == ambient_string_sharectx->activeHeap);
295 // requested logical copy in same heap: defer copy until write
296
297 (s.shareEditSet_owns_ulink){ false };
298
299 // make s alone in its shareEditSet
300 s.shareEditSet_prev = &s;
301 s.shareEditSet_next = &s;
302 } else {
303 verify( mode == SHARE_EDITS );
304 // sharing edits with source forces same heap as source (ignore context)
305
306 (s.shareEditSet_owns_ulink){ s2.shareEditSet_owns_ulink };
307
308 // s2 is logically const but not implementation const
309 string_res & s2mod = (string_res &) s2;
310
311 // insert s after s2 on shareEditSet
312 s.shareEditSet_next = s2mod.shareEditSet_next;
313 s.shareEditSet_prev = &s2mod;
314 s.shareEditSet_next->shareEditSet_prev = &s;
315 s.shareEditSet_prev->shareEditSet_next = &s;
316 }
317 }
318}
319
320static void assignEditSet(string_res & this, string_res * shareEditSetStartPeer, string_res * shareEditSetEndPeer,
321 char * resultSesStart,
322 size_t resultSesLnth,
323 HandleNode * resultPadPosition, size_t bsize ) {
324
325 char * beforeBegin = shareEditSetStartPeer->Handle.s;
326 size_t beforeLen = this.Handle.s - beforeBegin;
327
328 char * afterBegin = this.Handle.s + this.Handle.lnth;
329 size_t afterLen = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - afterBegin;
330
331 size_t oldLnth = this.Handle.lnth;
332
333 this.Handle.s = resultSesStart + beforeLen;
334 this.Handle.lnth = bsize;
335 if (resultPadPosition)
336 MoveThisAfter( this.Handle, *resultPadPosition );
337
338 // adjust all substring string and handle locations, and check if any substring strings are outside the new base string
339 char *limit = resultSesStart + resultSesLnth;
340 for (string_res * p = this.shareEditSet_next; p != &this; p = p->shareEditSet_next) {
341 verify (p->Handle.s >= beforeBegin);
342 if ( p->Handle.s >= afterBegin ) {
343 verify ( p->Handle.s <= afterBegin + afterLen );
344 verify ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen );
345 // p starts after the edit
346 // take start and end as end-anchored
347 size_t startOffsetFromEnd = afterBegin + afterLen - p->Handle.s;
348 p->Handle.s = limit - startOffsetFromEnd;
349 // p->Handle.lnth unaffected
350 } else if ( p->Handle.s <= beforeBegin + beforeLen ) {
351 // p starts before, or at the start of, the edit
352 if ( p->Handle.s + p->Handle.lnth <= beforeBegin + beforeLen ) {
353 // p ends before the edit
354 // take end as start-anchored too
355 // p->Handle.lnth unaffected
356 } else if ( p->Handle.s + p->Handle.lnth < afterBegin ) {
357 // p ends during the edit; p does not include the last character replaced
358 // clip end of p to end at start of edit
359 p->Handle.lnth = beforeLen - ( p->Handle.s - beforeBegin );
360 } else {
361 // p ends after the edit
362 verify ( p->Handle.s + p->Handle.lnth <= afterBegin + afterLen );
363 // take end as end-anchored
364 // stretch-shrink p according to the edit
365 p->Handle.lnth += this.Handle.lnth;
366 p->Handle.lnth -= oldLnth;
367 }
368 // take start as start-anchored
369 size_t startOffsetFromStart = p->Handle.s - beforeBegin;
370 p->Handle.s = resultSesStart + startOffsetFromStart;
371 } else {
372 verify ( p->Handle.s < afterBegin );
373 // p starts during the edit
374 verify( p->Handle.s + p->Handle.lnth >= beforeBegin + beforeLen );
375 if ( p->Handle.s + p->Handle.lnth < afterBegin ) {
376 // p ends during the edit; p does not include the last character replaced
377 // set p to empty string at start of edit
378 p->Handle.s = this.Handle.s;
379 p->Handle.lnth = 0;
380 } else {
381 // p includes the end of the edit
382 // clip start of p to start at end of edit
383 int charsToClip = afterBegin - p->Handle.s;
384 p->Handle.s = this.Handle.s + this.Handle.lnth;
385 p->Handle.lnth -= charsToClip;
386 }
387 }
388 if (resultPadPosition)
389 MoveThisAfter( p->Handle, *resultPadPosition ); // move substring handle to maintain sorted order by string position
390 }
391}
392
393static string_res & assign_(string_res &this, const char* buffer, size_t bsize, const string_res & valSrc) {
394
395 // traverse the incumbent share-edit set (SES) to recover the range of a base string to which `this` belongs
396 string_res * shareEditSetStartPeer = & this;
397 string_res * shareEditSetEndPeer = & this;
398 for (string_res * editPeer = this.shareEditSet_next; editPeer != &this; editPeer = editPeer->shareEditSet_next) {
399 if ( editPeer->Handle.s < shareEditSetStartPeer->Handle.s ) {
400 shareEditSetStartPeer = editPeer;
401 }
402 if ( shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth < editPeer->Handle.s + editPeer->Handle.lnth) {
403 shareEditSetEndPeer = editPeer;
404 }
405 }
406
407 verify( shareEditSetEndPeer->Handle.s >= shareEditSetStartPeer->Handle.s );
408 size_t origEditSetLength = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - shareEditSetStartPeer->Handle.s;
409 verify( origEditSetLength >= this.Handle.lnth );
410
411 if ( this.shareEditSet_owns_ulink ) { // assigning to private context
412 // ok to overwrite old value within LHS
413 char * prefixStartOrig = shareEditSetStartPeer->Handle.s;
414 int prefixLen = this.Handle.s - prefixStartOrig;
415 char * suffixStartOrig = this.Handle.s + this.Handle.lnth;
416 int suffixLen = shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth - suffixStartOrig;
417
418 int delta = bsize - this.Handle.lnth;
419 if ( char * oldBytes = VbyteTryAdjustLast( *this.Handle.ulink, delta ) ) {
420 // growing: copy from old to new
421 char * dest = VbyteAlloc( *this.Handle.ulink, origEditSetLength + delta );
422 char *destCursor = dest; memcpy(destCursor, prefixStartOrig, prefixLen);
423 destCursor += prefixLen; memcpy(destCursor, buffer , bsize );
424 destCursor += bsize; memcpy(destCursor, suffixStartOrig, suffixLen);
425 assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer,
426 dest,
427 origEditSetLength + delta,
428 0p, bsize);
429 free( oldBytes );
430 } else {
431 // room is already allocated in-place: bubble suffix and overwite middle
432 memmove( suffixStartOrig + delta, suffixStartOrig, suffixLen );
433 memcpy( this.Handle.s, buffer, bsize );
434
435 assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer,
436 shareEditSetStartPeer->Handle.s,
437 origEditSetLength + delta,
438 0p, bsize);
439 }
440
441 } else if ( // assigning to shared context
442 this.Handle.lnth == origEditSetLength && // overwriting entire run of SES
443 & valSrc && // sourcing from a managed string
444 valSrc.Handle.ulink == this.Handle.ulink ) { // sourcing from same heap
445
446 // SES's result will only use characters from the source string => reuse source
447 assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer,
448 valSrc.Handle.s,
449 valSrc.Handle.lnth,
450 &((string_res&)valSrc).Handle, bsize);
451
452 } else {
453 // overwriting a proper substring of some string: mash characters from old and new together (copy on write)
454 // OR we are importing characters: need to copy eagerly (can't refer to source)
455
456 // full string is from start of shareEditSetStartPeer thru end of shareEditSetEndPeer
457 // `this` occurs in the middle of it, to be replaced
458 // build up the new text in `pasting`
459
460 string_res pasting = {
461 * this.Handle.ulink, // maintain same heap, regardless of context
462 shareEditSetStartPeer->Handle.s, // start of SES
463 this.Handle.s - shareEditSetStartPeer->Handle.s }; // length of SES, before this
464 append( pasting,
465 buffer, // start of replacement for this
466 bsize ); // length of replacement for this
467 append( pasting,
468 this.Handle.s + this.Handle.lnth, // start of SES after this
469 shareEditSetEndPeer->Handle.s + shareEditSetEndPeer->Handle.lnth -
470 (this.Handle.s + this.Handle.lnth) ); // length of SES, after this
471
472 // The above string building can trigger compaction.
473 // The reference points (that are arguments of the string building) may move during that building.
474 // From this point on, they are stable.
475
476 assignEditSet(this, shareEditSetStartPeer, shareEditSetEndPeer,
477 pasting.Handle.s,
478 pasting.Handle.lnth,
479 &pasting.Handle, bsize);
480 }
481
482 return this;
483}
484
485string_res & assign(string_res &this, const char* buffer, size_t bsize) {
486 return assign_(this, buffer, bsize, *0p);
487}
488
489string_res & ?=?(string_res &s, char other) {
490 return assign(s, &other, 1);
491}
492
493// Copy assignment operator
494string_res & ?=?(string_res & this, const string_res & rhs) with( this ) {
495 return assign_(this, rhs.Handle.s, rhs.Handle.lnth, rhs);
496}
497
498string_res & ?=?(string_res & this, string_res & rhs) with( this ) {
499 const string_res & rhs2 = rhs;
500 return this = rhs2;
501}
502
503
504// Destructor
505void ^?{}(string_res &s) with(s) {
506 // much delegated to implied ^VbyteSM
507
508 // sever s from its share-edit peers, if any (four no-ops when already solo)
509 s.shareEditSet_prev->shareEditSet_next = s.shareEditSet_next;
510 s.shareEditSet_next->shareEditSet_prev = s.shareEditSet_prev;
511 // s.shareEditSet_next = &s;
512 // s.shareEditSet_prev = &s;
513
514 if (shareEditSet_owns_ulink && s.shareEditSet_next == &s) { // last one out
515 delete( s.Handle.ulink );
516 }
517}
518
519
520// Returns the character at the given index
521// With unicode support, this may be different from just the byte at the given
522// offset from the start of the string.
523char ?[?](const string_res &s, size_t index) with(s) {
524 //TODO: Check if index is valid (no exceptions yet)
525 return Handle.s[index];
526}
527
528void assignAt(const string_res &s, size_t index, char val) {
529 string_res editZone = { s, SHARE_EDITS, index, index+1 };
530 assign(editZone, &val, 1);
531}
532
533
534///////////////////////////////////////////////////////////////////
535// Concatenation
536
537void append(string_res &str1, const char * buffer, size_t bsize) {
538 size_t clnth = str1.Handle.lnth + bsize;
539 if ( str1.Handle.s + str1.Handle.lnth == buffer ) { // already juxtapose ?
540 // no-op
541 } else { // must copy some text
542 if ( str1.Handle.s + str1.Handle.lnth == VbyteAlloc(*str1.Handle.ulink, 0) ) { // str1 at end of string area ?
543 VbyteAlloc( *str1.Handle.ulink, bsize ); // create room for 2nd part at the end of string area
544 } else { // copy the two parts
545 char * str1newBuf = VbyteAlloc( *str1.Handle.ulink, clnth );
546 char * str1oldBuf = str1.Handle.s; // must read after VbyteAlloc call in case it gs's
547 str1.Handle.s = str1newBuf;
548 memcpy( str1.Handle.s, str1oldBuf, str1.Handle.lnth );
549 } // if
550 memcpy( str1.Handle.s + str1.Handle.lnth, buffer, bsize );
551 } // if
552 str1.Handle.lnth = clnth;
553}
554
555void ?+=?(string_res &str1, const string_res &str2) {
556 append( str1, str2.Handle.s, str2.Handle.lnth );
557}
558
559void ?+=?(string_res &s, char other) {
560 append( s, &other, 1 );
561}
562
563
564
565
566
567//////////////////////////////////////////////////////////
568// Comparisons
569
570
571bool ?==?(const string_res &s1, const string_res &s2) {
572 return ByteCmp( s1.Handle.s, 0, s1.Handle.lnth, s2.Handle.s, 0, s2.Handle.lnth) == 0;
573}
574
575bool ?!=?(const string_res &s1, const string_res &s2) {
576 return !(s1 == s2);
577}
578bool ?==?(const string_res &s, const char* other) {
579 string_res sother = other;
580 return s == sother;
581}
582bool ?!=?(const string_res &s, const char* other) {
583 return !(s == other);
584}
585
586
587//////////////////////////////////////////////////////////
588// Search
589
590bool contains(const string_res &s, char ch) {
591 for (i; size(s)) {
592 if (s[i] == ch) return true;
593 }
594 return false;
595}
596
597int find(const string_res &s, char search) {
598 return findFrom(s, 0, search);
599}
600
601int findFrom(const string_res &s, size_t fromPos, char search) {
602 // FIXME: This paricular overload (find of single char) is optimized to use memchr.
603 // The general overload (find of string, memchr applying to its first character) and `contains` should be adjusted to match.
604 char * searchFrom = s.Handle.s + fromPos;
605 size_t searchLnth = s.Handle.lnth - fromPos;
606 int searchVal = search;
607 char * foundAt = (char *) memchr(searchFrom, searchVal, searchLnth);
608 if (foundAt == 0p) return s.Handle.lnth;
609 else return foundAt - s.Handle.s;
610}
611
612int find(const string_res &s, const string_res &search) {
613 return findFrom(s, 0, search);
614}
615
616int findFrom(const string_res &s, size_t fromPos, const string_res &search) {
617 return findFrom(s, fromPos, search.Handle.s, search.Handle.lnth);
618}
619
620int find(const string_res &s, const char* search) {
621 return findFrom(s, 0, search);
622}
623int findFrom(const string_res &s, size_t fromPos, const char* search) {
624 return findFrom(s, fromPos, search, strlen(search));
625}
626
627int find(const string_res &s, const char* search, size_t searchsize) {
628 return findFrom(s, 0, search, searchsize);
629}
630
631int findFrom(const string_res &s, size_t fromPos, const char* search, size_t searchsize) {
632
633 /* Remaining implementations essentially ported from Sunjay's work */
634
635
636 // FIXME: This is a naive algorithm. We probably want to switch to someting
637 // like Boyer-Moore in the future.
638 // https://en.wikipedia.org/wiki/String_searching_algorithm
639
640 // Always find the empty string
641 if (searchsize == 0) {
642 return 0;
643 }
644
645 for (size_t i = fromPos; i < s.Handle.lnth; i++) {
646 size_t remaining = s.Handle.lnth - i;
647 // Never going to find the search string if the remaining string is
648 // smaller than search
649 if (remaining < searchsize) {
650 break;
651 }
652
653 bool matched = true;
654 for (size_t j = 0; j < searchsize; j++) {
655 if (search[j] != s.Handle.s[i + j]) {
656 matched = false;
657 break;
658 }
659 }
660 if (matched) {
661 return i;
662 }
663 }
664
665 return s.Handle.lnth;
666}
667
668bool includes(const string_res &s, const string_res &search) {
669 return includes(s, search.Handle.s, search.Handle.lnth);
670}
671
672bool includes(const string_res &s, const char* search) {
673 return includes(s, search, strlen(search));
674}
675
676bool includes(const string_res &s, const char* search, size_t searchsize) {
677 return find(s, search, searchsize) < s.Handle.lnth;
678}
679
680bool startsWith(const string_res &s, const string_res &prefix) {
681 return startsWith(s, prefix.Handle.s, prefix.Handle.lnth);
682}
683
684bool startsWith(const string_res &s, const char* prefix) {
685 return startsWith(s, prefix, strlen(prefix));
686}
687
688bool startsWith(const string_res &s, const char* prefix, size_t prefixsize) {
689 if (s.Handle.lnth < prefixsize) {
690 return false;
691 }
692 return memcmp(s.Handle.s, prefix, prefixsize) == 0;
693}
694
695bool endsWith(const string_res &s, const string_res &suffix) {
696 return endsWith(s, suffix.Handle.s, suffix.Handle.lnth);
697}
698
699bool endsWith(const string_res &s, const char* suffix) {
700 return endsWith(s, suffix, strlen(suffix));
701}
702
703bool endsWith(const string_res &s, const char* suffix, size_t suffixsize) {
704 if (s.Handle.lnth < suffixsize) {
705 return false;
706 }
707 // Amount to offset the bytes pointer so that we are comparing the end of s
708 // to suffix. s.bytes + offset should be the first byte to compare against suffix
709 size_t offset = s.Handle.lnth - suffixsize;
710 return memcmp(s.Handle.s + offset, suffix, suffixsize) == 0;
711}
712
713 /* Back to Mike's work */
714
715
716///////////////////////////////////////////////////////////////////////////
717// charclass, include, exclude
718
719void ?{}( charclass_res & this, const string_res & chars) {
720 (this){ chars.Handle.s, chars.Handle.lnth };
721}
722
723void ?{}( charclass_res & this, const char * chars ) {
724 (this){ chars, strlen(chars) };
725}
726
727void ?{}( charclass_res & this, const char * chars, size_t charssize ) {
728 (this.chars){ chars, charssize };
729 // now sort it ?
730}
731
732void ^?{}( charclass_res & this ) {
733 ^(this.chars){};
734}
735
736static bool test( const charclass_res & mask, char c ) {
737 // instead, use sorted char list?
738 return contains( mask.chars, c );
739}
740
741int exclude(const string_res &s, const charclass_res &mask) {
742 for (int i = 0; i < size(s); i++) {
743 if ( test(mask, s[i]) ) return i;
744 }
745 return size(s);
746}
747
748int include(const string_res &s, const charclass_res &mask) {
749 for (int i = 0; i < size(s); i++) {
750 if ( ! test(mask, s[i]) ) return i;
751 }
752 return size(s);
753}
754
755//######################### VbyteHeap "implementation" #########################
756
757
758// Add a new HandleNode node n after the current HandleNode node.
759
760static void AddThisAfter( HandleNode & this, HandleNode & n ) with(this) {
761#ifdef VbyteDebug
762 serr | "enter:AddThisAfter, this:" | &this | " n:" | &n;
763#endif // VbyteDebug
764 // Performance note: we are on the critical path here. MB has ensured that the verifies don't contribute to runtime (are compiled away, like they're supposed to be).
765 verify( n.ulink != 0p );
766 verify( this.ulink == n.ulink );
767 flink = n.flink;
768 blink = &n;
769 n.flink->blink = &this;
770 n.flink = &this;
771#ifdef VbyteDebug
772 {
773 serr | "HandleList:";
774 serr | nlOff;
775 for ( HandleNode *ni = HeaderPtr->flink; ni != HeaderPtr; ni = ni->flink ) {
776 serr | "\tnode:" | ni | " lnth:" | ni->lnth | " s:" | (void *)ni->s | ",\"";
777 for ( int i = 0; i < ni->lnth; i += 1 ) {
778 serr | ni->s[i];
779 } // for
780 serr | "\" flink:" | ni->flink | " blink:" | ni->blink | nl;
781 } // for
782 serr | nlOn;
783 }
784 serr | "exit:AddThisAfter";
785#endif // VbyteDebug
786} // AddThisAfter
787
788
789// Delete the current HandleNode node.
790
791static void DeleteNode( HandleNode & this ) with(this) {
792#ifdef VbyteDebug
793 serr | "enter:DeleteNode, this:" | &this;
794#endif // VbyteDebug
795 flink->blink = blink;
796 blink->flink = flink;
797#ifdef VbyteDebug
798 serr | "exit:DeleteNode";
799#endif // VbyteDebug
800} // DeleteNode
801
802
803
804// Allocates specified storage for a string from byte-string area. If not enough space remains to perform the
805// allocation, the garbage collection routine is called.
806
807static char * VbyteAlloc( VbyteHeap & this, int size ) with(this) {
808#ifdef VbyteDebug
809 serr | "enter:VbyteAlloc, size:" | size;
810#endif // VbyteDebug
811 uintptr_t NoBytes;
812 char *r;
813
814 NoBytes = ( uintptr_t )EndVbyte + size;
815 if ( NoBytes > ( uintptr_t )ExtVbyte ) { // enough room for new byte-string ?
816 garbage( this, size ); // firer up the garbage collector
817 verify( (( uintptr_t )EndVbyte + size) <= ( uintptr_t )ExtVbyte && "garbage run did not free up required space" );
818 } // if
819 r = EndVbyte;
820 EndVbyte += size;
821#ifdef VbyteDebug
822 serr | "exit:VbyteAlloc, r:" | (void *)r | " EndVbyte:" | (void *)EndVbyte | " ExtVbyte:" | ExtVbyte;
823#endif // VbyteDebug
824 return r;
825} // VbyteAlloc
826
827
828// Adjusts the last allocation in this heap by delta bytes, or resets this heap to be able to offer
829// new allocations of its original size + delta bytes. Positive delta means bigger;
830// negative means smaller. A null return indicates that the original heap location has room for
831// the requested growth. A non-null return indicates that copying to a new location is required
832// but has not been done; the returned value is the old heap storage location; `this` heap is
833// modified to reference the new location. In the copy-requred case, the caller should use
834// VbyteAlloc to claim the new space, while doing optimal copying from old to new, then free old.
835
836static char * VbyteTryAdjustLast( VbyteHeap & this, int delta ) with(this) {
837
838 if ( ( uintptr_t )EndVbyte + delta <= ( uintptr_t )ExtVbyte ) {
839 // room available
840 EndVbyte += delta;
841 return 0p;
842 }
843
844 char *oldBytes = StartVbyte;
845
846 NoOfExtensions += 1;
847 CurrSize *= 2;
848 StartVbyte = EndVbyte = TEMP_ALLOC(char, CurrSize);
849 ExtVbyte = StartVbyte + CurrSize;
850
851 return oldBytes;
852}
853
854
855// Move an existing HandleNode node h somewhere after the current HandleNode node so that it is in ascending order by
856// the address in the byte string area.
857
858static void MoveThisAfter( HandleNode & this, const HandleNode & h ) with(this) {
859#ifdef VbyteDebug
860 serr | "enter:MoveThisAfter, this:" | & this | " h:" | & h;
861#endif // VbyteDebug
862 verify( h.ulink != 0p );
863 verify( this.ulink == h.ulink );
864 if ( s < h.s ) { // check argument values
865 // serr | "VbyteSM: Error - Cannot move byte string starting at:" | s | " after byte string starting at:"
866 // | ( h->s ) | " and keep handles in ascending order";
867 // exit(-1 );
868 verify( 0 && "VbyteSM: Error - Cannot move byte strings as requested and keep handles in ascending order");
869 } // if
870
871 HandleNode *i;
872 for ( i = h.flink; i->s != 0 && s > ( i->s ); i = i->flink ); // find the position for this node after h
873 if ( & this != i->blink ) {
874 DeleteNode( this );
875 AddThisAfter( this, *i->blink );
876 } // if
877#ifdef VbyteDebug
878 {
879 serr | "HandleList:";
880 serr | nlOff;
881 for ( HandleNode *n = HeaderPtr->flink; n != HeaderPtr; n = n->flink ) {
882 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
883 for ( int i = 0; i < n->lnth; i += 1 ) {
884 serr | n->s[i];
885 } // for
886 serr | "\" flink:" | n->flink | " blink:" | n->blink | nl;
887 } // for
888 serr | nlOn;
889 }
890 serr | "exit:MoveThisAfter";
891#endif // VbyteDebug
892} // MoveThisAfter
893
894
895
896
897
898//######################### VbyteHeap #########################
899
900// Compare two byte strings in the byte-string area. The routine returns the following values:
901//
902// 1 => Src1-byte-string > Src2-byte-string
903// 0 => Src1-byte-string = Src2-byte-string
904// -1 => Src1-byte-string < Src2-byte-string
905
906int ByteCmp( char *Src1, int Src1Start, int Src1Lnth, char *Src2, int Src2Start, int Src2Lnth ) {
907#ifdef VbyteDebug
908 serr | "enter:ByteCmp, Src1Start:" | Src1Start | " Src1Lnth:" | Src1Lnth | " Src2Start:" | Src2Start | " Src2Lnth:" | Src2Lnth;
909#endif // VbyteDebug
910 int cmp;
911
912 CharZip: for ( int i = 0; ; i += 1 ) {
913 if ( i == Src2Lnth - 1 ) {
914 for ( ; ; i += 1 ) {
915 if ( i == Src1Lnth - 1 ) {
916 cmp = 0;
917 break CharZip;
918 } // exit
919 if ( Src1[Src1Start + i] != ' ') {
920 // SUSPECTED BUG: this could be be why Peter got the bug report about == " " (why is this case here at all?)
921 cmp = 1;
922 break CharZip;
923 } // exit
924 } // for
925 } // exit
926 if ( i == Src1Lnth - 1 ) {
927 for ( ; ; i += 1 ) {
928 if ( i == Src2Lnth - 1 ) {
929 cmp = 0;
930 break CharZip;
931 } // exit
932 if ( Src2[Src2Start + i] != ' ') {
933 cmp = -1;
934 break CharZip;
935 } // exit
936 } // for
937 } // exit
938 if ( Src2[Src2Start + i] != Src1[Src1Start+ i]) {
939 cmp = Src1[Src1Start + i] > Src2[Src2Start + i] ? 1 : -1;
940 break CharZip;
941 } // exit
942 } // for
943#ifdef VbyteDebug
944 serr | "exit:ByteCmp, cmp:" | cmp;
945#endif // VbyteDebug
946 return cmp;
947} // ByteCmp
948
949
950// The compaction moves all of the byte strings currently in use to the beginning of the byte-string area and modifies
951// the handles to reflect the new positions of the byte strings. Compaction assumes that the handle list is in ascending
952// order by pointers into the byte-string area. The strings associated with substrings do not have to be moved because
953// the containing string has been moved. Hence, they only require that their string pointers be adjusted.
954
955void compaction(VbyteHeap & this) with(this) {
956 HandleNode *h;
957 char *obase, *nbase, *limit;
958
959 NoOfCompactions += 1;
960 EndVbyte = StartVbyte;
961 h = Header.flink; // ignore header node
962 for (;;) {
963 memmove( EndVbyte, h->s, h->lnth );
964 obase = h->s;
965 h->s = EndVbyte;
966 nbase = h->s;
967 EndVbyte += h->lnth;
968 limit = obase + h->lnth;
969 h = h->flink;
970
971 // check if any substrings are allocated within a string
972
973 for (;;) {
974 if ( h == &Header ) break; // end of header list ?
975 if ( h->s >= limit ) break; // outside of current string ?
976 h->s = nbase + (( uintptr_t )h->s - ( uintptr_t )obase );
977 h = h->flink;
978 } // for
979 if ( h == &Header ) break; // end of header list ?
980 } // for
981} // compaction
982
983
984static double heap_expansion_freespace_threshold = 0.1; // default inherited from prior work: expand heap when less than 10% "free" (i.e. garbage)
985 // probably an unreasonable default, but need to assess early-round tests on changing it
986
987void TUNING_set_string_heap_liveness_threshold( double val ) {
988 heap_expansion_freespace_threshold = 1.0 - val;
989}
990
991
992// Garbage determines the amount of free space left in the heap and then reduces, leave the same, or extends the size of
993// the heap. The heap is then compacted in the existing heap or into the newly allocated heap.
994
995void garbage(VbyteHeap & this, int minreq ) with(this) {
996#ifdef VbyteDebug
997 serr | "enter:garbage";
998 {
999 serr | "HandleList:";
1000 for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) {
1001 serr | nlOff;
1002 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
1003 for ( int i = 0; i < n->lnth; i += 1 ) {
1004 serr | n->s[i];
1005 } // for
1006 serr | nlOn;
1007 serr | "\" flink:" | n->flink | " blink:" | n->blink;
1008 } // for
1009 }
1010#endif // VbyteDebug
1011 int AmountUsed, AmountFree;
1012
1013 AmountUsed = 0;
1014 for ( HandleNode *i = Header.flink; i != &Header; i = i->flink ) { // calculate amount of byte area used
1015 AmountUsed += i->lnth;
1016 } // for
1017 AmountFree = ( uintptr_t )ExtVbyte - ( uintptr_t )StartVbyte - AmountUsed;
1018
1019 if ( ( double ) AmountFree < ( CurrSize * heap_expansion_freespace_threshold ) || AmountFree < minreq ) { // free space less than threshold or not enough to serve cur request
1020
1021 extend( this, max( CurrSize, minreq ) ); // extend the heap
1022
1023 // Peter says, "This needs work before it should be used."
1024 // } else if ( AmountFree > CurrSize / 2 ) { // free space greater than 3 times the initial allocation ?
1025 // reduce(( AmountFree / CurrSize - 3 ) * CurrSize ); // reduce the memory
1026
1027 // `extend` implies a `compaction` during the copy
1028
1029 } else {
1030 compaction(this); // in-place
1031 }// if
1032#ifdef VbyteDebug
1033 {
1034 serr | "HandleList:";
1035 for ( HandleNode *n = Header.flink; n != &Header; n = n->flink ) {
1036 serr | nlOff;
1037 serr | "\tnode:" | n | " lnth:" | n->lnth | " s:" | (void *)n->s | ",\"";
1038 for ( int i = 0; i < n->lnth; i += 1 ) {
1039 serr | n->s[i];
1040 } // for
1041 serr | nlOn;
1042 serr | "\" flink:" | n->flink | " blink:" | n->blink;
1043 } // for
1044 }
1045 serr | "exit:garbage";
1046#endif // VbyteDebug
1047} // garbage
1048
1049#undef VbyteDebug
1050
1051
1052
1053// Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string
1054// area is deleted.
1055
1056void extend( VbyteHeap & this, int size ) with (this) {
1057#ifdef VbyteDebug
1058 serr | "enter:extend, size:" | size;
1059#endif // VbyteDebug
1060 char *OldStartVbyte;
1061
1062 NoOfExtensions += 1;
1063 OldStartVbyte = StartVbyte; // save previous byte area
1064
1065 CurrSize += size > InitSize ? size : InitSize; // minimum extension, initial size
1066 StartVbyte = EndVbyte = TEMP_ALLOC(char, CurrSize);
1067 ExtVbyte = (void *)( StartVbyte + CurrSize );
1068 compaction(this); // copy from old heap to new & adjust pointers to new heap
1069 free( OldStartVbyte ); // release old heap
1070#ifdef VbyteDebug
1071 serr | "exit:extend, CurrSize:" | CurrSize;
1072#endif // VbyteDebug
1073} // extend
1074
1075//WIP
1076#if 0
1077
1078// Extend the size of the byte-string area by creating a new area and copying the old area into it. The old byte-string
1079// area is deleted.
1080
1081void VbyteHeap::reduce( int size ) {
1082#ifdef VbyteDebug
1083 serr | "enter:reduce, size:" | size;
1084#endif // VbyteDebug
1085 char *OldStartVbyte;
1086
1087 NoOfReductions += 1;
1088 OldStartVbyte = StartVbyte; // save previous byte area
1089
1090 CurrSize -= size;
1091 StartVbyte = EndVbyte = new char[CurrSize];
1092 ExtVbyte = (void *)( StartVbyte + CurrSize );
1093 compaction(); // copy from old heap to new & adjust pointers to new heap
1094 delete OldStartVbyte; // release old heap
1095#ifdef VbyteDebug
1096 serr | "exit:reduce, CurrSize:" | CurrSize;
1097#endif // VbyteDebug
1098} // reduce
1099
1100
1101#endif
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