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1 /* SDSLib, A C dynamic strings library
2 *
3 * Copyright (c) 2006-2010, Salvatore Sanfilippo <antirez at gmail dot com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are met:
8 *
9 * * Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * * Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * * Neither the name of Redis nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without
16 * specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 *
30 * History:
31 *
32 * - 22 March 2011: History section created on top of sds.c
33 * - 22 March 2011: Fixed a problem with "\xab" escapes convertion in
34 * function sdssplitargs().
35 */
36
37 #define SDS_ABORT_ON_OOM
38
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <ctype.h>
43 #include "sds.h"
44 #include "zmalloc.h"
45
46 static void sdsOomAbort(void) {
47 fprintf(stderr,"SDS: Out Of Memory (SDS_ABORT_ON_OOM defined)\n");
48 abort();
49 }
50
51 sds sdsnewlen(const void *init, size_t initlen) {
52 struct sdshdr *sh;
53
54 if (init) {
55 sh = zmalloc(sizeof(struct sdshdr)+initlen+1);
56 } else {
57 sh = zcalloc(sizeof(struct sdshdr)+initlen+1);
58 }
59 #ifdef SDS_ABORT_ON_OOM
60 if (sh == NULL) sdsOomAbort();
61 #else
62 if (sh == NULL) return NULL;
63 #endif
64 sh->len = initlen;
65 sh->free = 0;
66 if (initlen && init)
67 memcpy(sh->buf, init, initlen);
68 sh->buf[initlen] = '\0';
69 return (char*)sh->buf;
70 }
71
72 sds sdsempty(void) {
73 return sdsnewlen("",0);
74 }
75
76 sds sdsnew(const char *init) {
77 size_t initlen = (init == NULL) ? 0 : strlen(init);
78 return sdsnewlen(init, initlen);
79 }
80
81 sds sdsdup(const sds s) {
82 return sdsnewlen(s, sdslen(s));
83 }
84
85 void sdsfree(sds s) {
86 if (s == NULL) return;
87 zfree(s-sizeof(struct sdshdr));
88 }
89
90 void sdsupdatelen(sds s) {
91 struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
92 int reallen = strlen(s);
93 sh->free += (sh->len-reallen);
94 sh->len = reallen;
95 }
96
97 void sdsclear(sds s) {
98 struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
99 sh->free += sh->len;
100 sh->len = 0;
101 sh->buf[0] = '\0';
102 }
103
104 static sds sdsMakeRoomFor(sds s, size_t addlen) {
105 struct sdshdr *sh, *newsh;
106 size_t free = sdsavail(s);
107 size_t len, newlen;
108
109 if (free >= addlen) return s;
110 len = sdslen(s);
111 sh = (void*) (s-(sizeof(struct sdshdr)));
112 newlen = (len+addlen)*2;
113 newsh = zrealloc(sh, sizeof(struct sdshdr)+newlen+1);
114 #ifdef SDS_ABORT_ON_OOM
115 if (newsh == NULL) sdsOomAbort();
116 #else
117 if (newsh == NULL) return NULL;
118 #endif
119
120 newsh->free = newlen - len;
121 return newsh->buf;
122 }
123
124 /* Grow the sds to have the specified length. Bytes that were not part of
125 * the original length of the sds will be set to zero. */
126 sds sdsgrowzero(sds s, size_t len) {
127 struct sdshdr *sh = (void*)(s-(sizeof(struct sdshdr)));
128 size_t totlen, curlen = sh->len;
129
130 if (len <= curlen) return s;
131 s = sdsMakeRoomFor(s,len-curlen);
132 if (s == NULL) return NULL;
133
134 /* Make sure added region doesn't contain garbage */
135 sh = (void*)(s-(sizeof(struct sdshdr)));
136 memset(s+curlen,0,(len-curlen+1)); /* also set trailing \0 byte */
137 totlen = sh->len+sh->free;
138 sh->len = len;
139 sh->free = totlen-sh->len;
140 return s;
141 }
142
143 sds sdscatlen(sds s, void *t, size_t len) {
144 struct sdshdr *sh;
145 size_t curlen = sdslen(s);
146
147 s = sdsMakeRoomFor(s,len);
148 if (s == NULL) return NULL;
149 sh = (void*) (s-(sizeof(struct sdshdr)));
150 memcpy(s+curlen, t, len);
151 sh->len = curlen+len;
152 sh->free = sh->free-len;
153 s[curlen+len] = '\0';
154 return s;
155 }
156
157 sds sdscat(sds s, char *t) {
158 return sdscatlen(s, t, strlen(t));
159 }
160
161 sds sdscpylen(sds s, char *t, size_t len) {
162 struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
163 size_t totlen = sh->free+sh->len;
164
165 if (totlen < len) {
166 s = sdsMakeRoomFor(s,len-sh->len);
167 if (s == NULL) return NULL;
168 sh = (void*) (s-(sizeof(struct sdshdr)));
169 totlen = sh->free+sh->len;
170 }
171 memcpy(s, t, len);
172 s[len] = '\0';
173 sh->len = len;
174 sh->free = totlen-len;
175 return s;
176 }
177
178 sds sdscpy(sds s, char *t) {
179 return sdscpylen(s, t, strlen(t));
180 }
181
182 sds sdscatvprintf(sds s, const char *fmt, va_list ap) {
183 va_list cpy;
184 char *buf, *t;
185 size_t buflen = 16;
186
187 while(1) {
188 buf = zmalloc(buflen);
189 #ifdef SDS_ABORT_ON_OOM
190 if (buf == NULL) sdsOomAbort();
191 #else
192 if (buf == NULL) return NULL;
193 #endif
194 buf[buflen-2] = '\0';
195 va_copy(cpy,ap);
196 vsnprintf(buf, buflen, fmt, cpy);
197 if (buf[buflen-2] != '\0') {
198 zfree(buf);
199 buflen *= 2;
200 continue;
201 }
202 break;
203 }
204 t = sdscat(s, buf);
205 zfree(buf);
206 return t;
207 }
208
209 sds sdscatprintf(sds s, const char *fmt, ...) {
210 va_list ap;
211 char *t;
212 va_start(ap, fmt);
213 t = sdscatvprintf(s,fmt,ap);
214 va_end(ap);
215 return t;
216 }
217
218 sds sdstrim(sds s, const char *cset) {
219 struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
220 char *start, *end, *sp, *ep;
221 size_t len;
222
223 sp = start = s;
224 ep = end = s+sdslen(s)-1;
225 while(sp <= end && strchr(cset, *sp)) sp++;
226 while(ep > start && strchr(cset, *ep)) ep--;
227 len = (sp > ep) ? 0 : ((ep-sp)+1);
228 if (sh->buf != sp) memmove(sh->buf, sp, len);
229 sh->buf[len] = '\0';
230 sh->free = sh->free+(sh->len-len);
231 sh->len = len;
232 return s;
233 }
234
235 sds sdsrange(sds s, int start, int end) {
236 struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
237 size_t newlen, len = sdslen(s);
238
239 if (len == 0) return s;
240 if (start < 0) {
241 start = len+start;
242 if (start < 0) start = 0;
243 }
244 if (end < 0) {
245 end = len+end;
246 if (end < 0) end = 0;
247 }
248 newlen = (start > end) ? 0 : (end-start)+1;
249 if (newlen != 0) {
250 if (start >= (signed)len) {
251 newlen = 0;
252 } else if (end >= (signed)len) {
253 end = len-1;
254 newlen = (start > end) ? 0 : (end-start)+1;
255 }
256 } else {
257 start = 0;
258 }
259 if (start && newlen) memmove(sh->buf, sh->buf+start, newlen);
260 sh->buf[newlen] = 0;
261 sh->free = sh->free+(sh->len-newlen);
262 sh->len = newlen;
263 return s;
264 }
265
266 void sdstolower(sds s) {
267 int len = sdslen(s), j;
268
269 for (j = 0; j < len; j++) s[j] = tolower(s[j]);
270 }
271
272 void sdstoupper(sds s) {
273 int len = sdslen(s), j;
274
275 for (j = 0; j < len; j++) s[j] = toupper(s[j]);
276 }
277
278 int sdscmp(sds s1, sds s2) {
279 size_t l1, l2, minlen;
280 int cmp;
281
282 l1 = sdslen(s1);
283 l2 = sdslen(s2);
284 minlen = (l1 < l2) ? l1 : l2;
285 cmp = memcmp(s1,s2,minlen);
286 if (cmp == 0) return l1-l2;
287 return cmp;
288 }
289
290 /* Split 's' with separator in 'sep'. An array
291 * of sds strings is returned. *count will be set
292 * by reference to the number of tokens returned.
293 *
294 * On out of memory, zero length string, zero length
295 * separator, NULL is returned.
296 *
297 * Note that 'sep' is able to split a string using
298 * a multi-character separator. For example
299 * sdssplit("foo_-_bar","_-_"); will return two
300 * elements "foo" and "bar".
301 *
302 * This version of the function is binary-safe but
303 * requires length arguments. sdssplit() is just the
304 * same function but for zero-terminated strings.
305 */
306 sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) {
307 int elements = 0, slots = 5, start = 0, j;
308 sds *tokens;
309
310 if (seplen < 1 || len < 0) return NULL;
311
312 tokens = zmalloc(sizeof(sds)*slots);
313 #ifdef SDS_ABORT_ON_OOM
314 if (tokens == NULL) sdsOomAbort();
315 #else
316 if (tokens == NULL) return NULL;
317 #endif
318
319 if (len == 0) {
320 *count = 0;
321 return tokens;
322 }
323 for (j = 0; j < (len-(seplen-1)); j++) {
324 /* make sure there is room for the next element and the final one */
325 if (slots < elements+2) {
326 sds *newtokens;
327
328 slots *= 2;
329 newtokens = zrealloc(tokens,sizeof(sds)*slots);
330 if (newtokens == NULL) {
331 #ifdef SDS_ABORT_ON_OOM
332 sdsOomAbort();
333 #else
334 goto cleanup;
335 #endif
336 }
337 tokens = newtokens;
338 }
339 /* search the separator */
340 if ((seplen == 1 && *(s+j) == sep[0]) || (memcmp(s+j,sep,seplen) == 0)) {
341 tokens[elements] = sdsnewlen(s+start,j-start);
342 if (tokens[elements] == NULL) {
343 #ifdef SDS_ABORT_ON_OOM
344 sdsOomAbort();
345 #else
346 goto cleanup;
347 #endif
348 }
349 elements++;
350 start = j+seplen;
351 j = j+seplen-1; /* skip the separator */
352 }
353 }
354 /* Add the final element. We are sure there is room in the tokens array. */
355 tokens[elements] = sdsnewlen(s+start,len-start);
356 if (tokens[elements] == NULL) {
357 #ifdef SDS_ABORT_ON_OOM
358 sdsOomAbort();
359 #else
360 goto cleanup;
361 #endif
362 }
363 elements++;
364 *count = elements;
365 return tokens;
366
367 #ifndef SDS_ABORT_ON_OOM
368 cleanup:
369 {
370 int i;
371 for (i = 0; i < elements; i++) sdsfree(tokens[i]);
372 zfree(tokens);
373 *count = 0;
374 return NULL;
375 }
376 #endif
377 }
378
379 void sdsfreesplitres(sds *tokens, int count) {
380 if (!tokens) return;
381 while(count--)
382 sdsfree(tokens[count]);
383 zfree(tokens);
384 }
385
386 sds sdsfromlonglong(long long value) {
387 char buf[32], *p;
388 unsigned long long v;
389
390 v = (value < 0) ? -value : value;
391 p = buf+31; /* point to the last character */
392 do {
393 *p-- = '0'+(v%10);
394 v /= 10;
395 } while(v);
396 if (value < 0) *p-- = '-';
397 p++;
398 return sdsnewlen(p,32-(p-buf));
399 }
400
401 sds sdscatrepr(sds s, char *p, size_t len) {
402 s = sdscatlen(s,"\"",1);
403 while(len--) {
404 switch(*p) {
405 case '\\':
406 case '"':
407 s = sdscatprintf(s,"\\%c",*p);
408 break;
409 case '\n': s = sdscatlen(s,"\\n",2); break;
410 case '\r': s = sdscatlen(s,"\\r",2); break;
411 case '\t': s = sdscatlen(s,"\\t",2); break;
412 case '\a': s = sdscatlen(s,"\\a",2); break;
413 case '\b': s = sdscatlen(s,"\\b",2); break;
414 default:
415 if (isprint(*p))
416 s = sdscatprintf(s,"%c",*p);
417 else
418 s = sdscatprintf(s,"\\x%02x",(unsigned char)*p);
419 break;
420 }
421 p++;
422 }
423 return sdscatlen(s,"\"",1);
424 }
425
426 /* Helper function for sdssplitargs() that returns non zero if 'c'
427 * is a valid hex digit. */
428 int is_hex_digit(char c) {
429 return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') ||
430 (c >= 'A' && c <= 'F');
431 }
432
433 /* Helper function for sdssplitargs() that converts an hex digit into an
434 * integer from 0 to 15 */
435 int hex_digit_to_int(char c) {
436 switch(c) {
437 case '0': return 0;
438 case '1': return 1;
439 case '2': return 2;
440 case '3': return 3;
441 case '4': return 4;
442 case '5': return 5;
443 case '6': return 6;
444 case '7': return 7;
445 case '8': return 8;
446 case '9': return 9;
447 case 'a': case 'A': return 10;
448 case 'b': case 'B': return 11;
449 case 'c': case 'C': return 12;
450 case 'd': case 'D': return 13;
451 case 'e': case 'E': return 14;
452 case 'f': case 'F': return 15;
453 default: return 0;
454 }
455 }
456
457 /* Split a line into arguments, where every argument can be in the
458 * following programming-language REPL-alike form:
459 *
460 * foo bar "newline are supported\n" and "\xff\x00otherstuff"
461 *
462 * The number of arguments is stored into *argc, and an array
463 * of sds is returned. The caller should sdsfree() all the returned
464 * strings and finally zfree() the array itself.
465 *
466 * Note that sdscatrepr() is able to convert back a string into
467 * a quoted string in the same format sdssplitargs() is able to parse.
468 */
469 sds *sdssplitargs(char *line, int *argc) {
470 char *p = line;
471 char *current = NULL;
472 char **vector = NULL;
473
474 *argc = 0;
475 while(1) {
476 /* skip blanks */
477 while(*p && isspace(*p)) p++;
478 if (*p) {
479 /* get a token */
480 int inq=0; /* set to 1 if we are in "quotes" */
481 int done=0;
482
483 if (current == NULL) current = sdsempty();
484 while(!done) {
485 if (inq) {
486 if (*p == '\\' && *(p+1) == 'x' &&
487 is_hex_digit(*(p+2)) &&
488 is_hex_digit(*(p+3)))
489 {
490 unsigned char byte;
491
492 byte = (hex_digit_to_int(*(p+2))*16)+
493 hex_digit_to_int(*(p+3));
494 current = sdscatlen(current,(char*)&byte,1);
495 p += 3;
496 } else if (*p == '\\' && *(p+1)) {
497 char c;
498
499 p++;
500 switch(*p) {
501 case 'n': c = '\n'; break;
502 case 'r': c = '\r'; break;
503 case 't': c = '\t'; break;
504 case 'b': c = '\b'; break;
505 case 'a': c = '\a'; break;
506 default: c = *p; break;
507 }
508 current = sdscatlen(current,&c,1);
509 } else if (*p == '"') {
510 /* closing quote must be followed by a space */
511 if (*(p+1) && !isspace(*(p+1))) goto err;
512 done=1;
513 } else if (!*p) {
514 /* unterminated quotes */
515 goto err;
516 } else {
517 current = sdscatlen(current,p,1);
518 }
519 } else {
520 switch(*p) {
521 case ' ':
522 case '\n':
523 case '\r':
524 case '\t':
525 case '\0':
526 done=1;
527 break;
528 case '"':
529 inq=1;
530 break;
531 default:
532 current = sdscatlen(current,p,1);
533 break;
534 }
535 }
536 if (*p) p++;
537 }
538 /* add the token to the vector */
539 vector = zrealloc(vector,((*argc)+1)*sizeof(char*));
540 vector[*argc] = current;
541 (*argc)++;
542 current = NULL;
543 } else {
544 return vector;
545 }
546 }
547
548 err:
549 while((*argc)--)
550 sdsfree(vector[*argc]);
551 zfree(vector);
552 if (current) sdsfree(current);
553 return NULL;
554 }
555
556 void sdssplitargs_free(sds *argv, int argc) {
557 int j;
558
559 for (j = 0 ;j < argc; j++) sdsfree(argv[j]);
560 zfree(argv);
561 }
562
563 /* Modify the string substituting all the occurrences of the set of
564 * characters specifed in the 'from' string to the corresponding character
565 * in the 'to' array.
566 *
567 * For instance: sdsmapchars(mystring, "ho", "01", 2)
568 * will have the effect of turning the string "hello" into "0ell1".
569 *
570 * The function returns the sds string pointer, that is always the same
571 * as the input pointer since no resize is needed. */
572 sds sdsmapchars(sds s, char *from, char *to, size_t setlen) {
573 size_t j, i, l = sdslen(s);
574
575 for (j = 0; j < l; j++) {
576 for (i = 0; i < setlen; i++) {
577 if (s[j] == from[i]) {
578 s[j] = to[i];
579 break;
580 }
581 }
582 }
583 return s;
584 }
585
586 #ifdef SDS_TEST_MAIN
587 #include <stdio.h>
588 #include "testhelp.h"
589
590 int main(void) {
591 {
592 sds x = sdsnew("foo"), y;
593
594 test_cond("Create a string and obtain the length",
595 sdslen(x) == 3 && memcmp(x,"foo\0",4) == 0)
596
597 sdsfree(x);
598 x = sdsnewlen("foo",2);
599 test_cond("Create a string with specified length",
600 sdslen(x) == 2 && memcmp(x,"fo\0",3) == 0)
601
602 x = sdscat(x,"bar");
603 test_cond("Strings concatenation",
604 sdslen(x) == 5 && memcmp(x,"fobar\0",6) == 0);
605
606 x = sdscpy(x,"a");
607 test_cond("sdscpy() against an originally longer string",
608 sdslen(x) == 1 && memcmp(x,"a\0",2) == 0)
609
610 x = sdscpy(x,"xyzxxxxxxxxxxyyyyyyyyyykkkkkkkkkk");
611 test_cond("sdscpy() against an originally shorter string",
612 sdslen(x) == 33 &&
613 memcmp(x,"xyzxxxxxxxxxxyyyyyyyyyykkkkkkkkkk\0",33) == 0)
614
615 sdsfree(x);
616 x = sdscatprintf(sdsempty(),"%d",123);
617 test_cond("sdscatprintf() seems working in the base case",
618 sdslen(x) == 3 && memcmp(x,"123\0",4) ==0)
619
620 sdsfree(x);
621 x = sdstrim(sdsnew("xxciaoyyy"),"xy");
622 test_cond("sdstrim() correctly trims characters",
623 sdslen(x) == 4 && memcmp(x,"ciao\0",5) == 0)
624
625 y = sdsrange(sdsdup(x),1,1);
626 test_cond("sdsrange(...,1,1)",
627 sdslen(y) == 1 && memcmp(y,"i\0",2) == 0)
628
629 sdsfree(y);
630 y = sdsrange(sdsdup(x),1,-1);
631 test_cond("sdsrange(...,1,-1)",
632 sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
633
634 sdsfree(y);
635 y = sdsrange(sdsdup(x),-2,-1);
636 test_cond("sdsrange(...,-2,-1)",
637 sdslen(y) == 2 && memcmp(y,"ao\0",3) == 0)
638
639 sdsfree(y);
640 y = sdsrange(sdsdup(x),2,1);
641 test_cond("sdsrange(...,2,1)",
642 sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
643
644 sdsfree(y);
645 y = sdsrange(sdsdup(x),1,100);
646 test_cond("sdsrange(...,1,100)",
647 sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
648
649 sdsfree(y);
650 y = sdsrange(sdsdup(x),100,100);
651 test_cond("sdsrange(...,100,100)",
652 sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
653
654 sdsfree(y);
655 sdsfree(x);
656 x = sdsnew("foo");
657 y = sdsnew("foa");
658 test_cond("sdscmp(foo,foa)", sdscmp(x,y) > 0)
659
660 sdsfree(y);
661 sdsfree(x);
662 x = sdsnew("bar");
663 y = sdsnew("bar");
664 test_cond("sdscmp(bar,bar)", sdscmp(x,y) == 0)
665
666 sdsfree(y);
667 sdsfree(x);
668 x = sdsnew("aar");
669 y = sdsnew("bar");
670 test_cond("sdscmp(bar,bar)", sdscmp(x,y) < 0)
671 }
672 test_report()
673 }
674 #endif