src/sds.c

   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
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <ctype.h>
  35 #include <assert.h>
  36 #include "sds.h"
  37 #include "zmalloc.h"
  38
  39 sds sdsnewlen(const void *init, size_t initlen) {
  40     struct sdshdr *sh;
  41
  42     if (init) {
  43         sh = zmalloc(sizeof(struct sdshdr)+initlen+1);
  44     } else {
  45         sh = zcalloc(sizeof(struct sdshdr)+initlen+1);
  46     }
  47     if (sh == NULL) return NULL;
  48     sh->len = initlen;
  49     sh->free = 0;
  50     if (initlen && init)
  51         memcpy(sh->buf, init, initlen);
  52     sh->buf[initlen] = '\0';
  53     return (char*)sh->buf;
  54 }
  55
  56 sds sdsempty(void) {
  57     return sdsnewlen("",0);
  58 }
  59
  60 sds sdsnew(const char *init) {
  61     size_t initlen = (init == NULL) ? 0 : strlen(init);
  62     return sdsnewlen(init, initlen);
  63 }
  64
  65 sds sdsdup(const sds s) {
  66     return sdsnewlen(s, sdslen(s));
  67 }
  68
  69 void sdsfree(sds s) {
  70     if (s == NULL) return;
  71     zfree(s-sizeof(struct sdshdr));
  72 }
  73
  74 void sdsupdatelen(sds s) {
  75     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
  76     int reallen = strlen(s);
  77     sh->free += (sh->len-reallen);
  78     sh->len = reallen;
  79 }
  80
  81 void sdsclear(sds s) {
  82     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
  83     sh->free += sh->len;
  84     sh->len = 0;
  85     sh->buf[0] = '\0';
  86 }
  87
  88 /* Enlarge the free space at the end of the sds string so that the caller
  89  * is sure that after calling this function can overwrite up to addlen
  90  * bytes after the end of the string, plus one more byte for nul term.
  91  *
  92  * Note: this does not change the *size* of the sds string as returned
  93  * by sdslen(), but only the free buffer space we have. */
  94 sds sdsMakeRoomFor(sds s, size_t addlen) {
  95     struct sdshdr *sh, *newsh;
  96     size_t free = sdsavail(s);
  97     size_t len, newlen;
  98
  99     if (free >= addlen) return s;
 100     len = sdslen(s);
 101     sh = (void*) (s-(sizeof(struct sdshdr)));
 102     newlen = (len+addlen);
 103     if (newlen < SDS_MAX_PREALLOC)
 104         newlen *= 2;
 105     else
 106         newlen += SDS_MAX_PREALLOC;
 107     newsh = zrealloc(sh, sizeof(struct sdshdr)+newlen+1);
 108     if (newsh == NULL) return NULL;
 109
 110     newsh->free = newlen - len;
 111     return newsh->buf;
 112 }
 113
 114 /* Increment the sds length and decrements the left free space at the
 115  * end of the string accordingly to 'incr'. Also set the null term
 116  * in the new end of the string.
 117  *
 118  * This function is used in order to fix the string length after the
 119  * user calls sdsMakeRoomFor(), writes something after the end of
 120  * the current string, and finally needs to set the new length.
 121  *
 122  * Note: it is possible to use a negative increment in order to
 123  * right-trim the string.
 124  *
 125  * Using sdsIncrLen() and sdsMakeRoomFor() it is possible to mount the
 126  * following schema to cat bytes coming from the kerenl to the end of an
 127  * sds string new things without copying into an intermediate buffer:
 128  *
 129  * oldlen = sdslen(s);
 130  * s = sdsMakeRoomFor(s, BUFFER_SIZE);
 131  * nread = read(fd, s+oldlen, BUFFER_SIZE);
 132  * ... check for nread <= 0 and handle it ...
 133  * sdsIncrLen(s, nhread);
 134  */
 135 void sdsIncrLen(sds s, int incr) {
 136     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
 137
 138     assert(sh->free >= incr);
 139     sh->len += incr;
 140     sh->free -= incr;
 141     assert(sh->free >= 0);
 142     s[sh->len] = '\0';
 143 }
 144
 145 /* Grow the sds to have the specified length. Bytes that were not part of
 146  * the original length of the sds will be set to zero. */
 147 sds sdsgrowzero(sds s, size_t len) {
 148     struct sdshdr *sh = (void*)(s-(sizeof(struct sdshdr)));
 149     size_t totlen, curlen = sh->len;
 150
 151     if (len <= curlen) return s;
 152     s = sdsMakeRoomFor(s,len-curlen);
 153     if (s == NULL) return NULL;
 154
 155     /* Make sure added region doesn't contain garbage */
 156     sh = (void*)(s-(sizeof(struct sdshdr)));
 157     memset(s+curlen,0,(len-curlen+1)); /* also set trailing \0 byte */
 158     totlen = sh->len+sh->free;
 159     sh->len = len;
 160     sh->free = totlen-sh->len;
 161     return s;
 162 }
 163
 164 sds sdscatlen(sds s, void *t, size_t len) {
 165     struct sdshdr *sh;
 166     size_t curlen = sdslen(s);
 167
 168     s = sdsMakeRoomFor(s,len);
 169     if (s == NULL) return NULL;
 170     sh = (void*) (s-(sizeof(struct sdshdr)));
 171     memcpy(s+curlen, t, len);
 172     sh->len = curlen+len;
 173     sh->free = sh->free-len;
 174     s[curlen+len] = '\0';
 175     return s;
 176 }
 177
 178 sds sdscat(sds s, char *t) {
 179     return sdscatlen(s, t, strlen(t));
 180 }
 181
 182 sds sdscatsds(sds s, sds t) {
 183     return sdscatlen(s, t, sdslen(t));
 184 }
 185
 186 sds sdscpylen(sds s, char *t, size_t len) {
 187     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
 188     size_t totlen = sh->free+sh->len;
 189
 190     if (totlen < len) {
 191         s = sdsMakeRoomFor(s,len-sh->len);
 192         if (s == NULL) return NULL;
 193         sh = (void*) (s-(sizeof(struct sdshdr)));
 194         totlen = sh->free+sh->len;
 195     }
 196     memcpy(s, t, len);
 197     s[len] = '\0';
 198     sh->len = len;
 199     sh->free = totlen-len;
 200     return s;
 201 }
 202
 203 sds sdscpy(sds s, char *t) {
 204     return sdscpylen(s, t, strlen(t));
 205 }
 206
 207 sds sdscatvprintf(sds s, const char *fmt, va_list ap) {
 208     va_list cpy;
 209     char *buf, *t;
 210     size_t buflen = 16;
 211
 212     while(1) {
 213         buf = zmalloc(buflen);
 214         if (buf == NULL) return NULL;
 215         buf[buflen-2] = '\0';
 216         va_copy(cpy,ap);
 217         vsnprintf(buf, buflen, fmt, cpy);
 218         if (buf[buflen-2] != '\0') {
 219             zfree(buf);
 220             buflen *= 2;
 221             continue;
 222         }
 223         break;
 224     }
 225     t = sdscat(s, buf);
 226     zfree(buf);
 227     return t;
 228 }
 229
 230 sds sdscatprintf(sds s, const char *fmt, ...) {
 231     va_list ap;
 232     char *t;
 233     va_start(ap, fmt);
 234     t = sdscatvprintf(s,fmt,ap);
 235     va_end(ap);
 236     return t;
 237 }
 238
 239 sds sdstrim(sds s, const char *cset) {
 240     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
 241     char *start, *end, *sp, *ep;
 242     size_t len;
 243
 244     sp = start = s;
 245     ep = end = s+sdslen(s)-1;
 246     while(sp <= end && strchr(cset, *sp)) sp++;
 247     while(ep > start && strchr(cset, *ep)) ep--;
 248     len = (sp > ep) ? 0 : ((ep-sp)+1);
 249     if (sh->buf != sp) memmove(sh->buf, sp, len);
 250     sh->buf[len] = '\0';
 251     sh->free = sh->free+(sh->len-len);
 252     sh->len = len;
 253     return s;
 254 }
 255
 256 sds sdsrange(sds s, int start, int end) {
 257     struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
 258     size_t newlen, len = sdslen(s);
 259
 260     if (len == 0) return s;
 261     if (start < 0) {
 262         start = len+start;
 263         if (start < 0) start = 0;
 264     }
 265     if (end < 0) {
 266         end = len+end;
 267         if (end < 0) end = 0;
 268     }
 269     newlen = (start > end) ? 0 : (end-start)+1;
 270     if (newlen != 0) {
 271         if (start >= (signed)len) {
 272             newlen = 0;
 273         } else if (end >= (signed)len) {
 274             end = len-1;
 275             newlen = (start > end) ? 0 : (end-start)+1;
 276         }
 277     } else {
 278         start = 0;
 279     }
 280     if (start && newlen) memmove(sh->buf, sh->buf+start, newlen);
 281     sh->buf[newlen] = 0;
 282     sh->free = sh->free+(sh->len-newlen);
 283     sh->len = newlen;
 284     return s;
 285 }
 286
 287 void sdstolower(sds s) {
 288     int len = sdslen(s), j;
 289
 290     for (j = 0; j < len; j++) s[j] = tolower(s[j]);
 291 }
 292
 293 void sdstoupper(sds s) {
 294     int len = sdslen(s), j;
 295
 296     for (j = 0; j < len; j++) s[j] = toupper(s[j]);
 297 }
 298
 299 int sdscmp(sds s1, sds s2) {
 300     size_t l1, l2, minlen;
 301     int cmp;
 302
 303     l1 = sdslen(s1);
 304     l2 = sdslen(s2);
 305     minlen = (l1 < l2) ? l1 : l2;
 306     cmp = memcmp(s1,s2,minlen);
 307     if (cmp == 0) return l1-l2;
 308     return cmp;
 309 }
 310
 311 /* Split 's' with separator in 'sep'. An array
 312  * of sds strings is returned. *count will be set
 313  * by reference to the number of tokens returned.
 314  *
 315  * On out of memory, zero length string, zero length
 316  * separator, NULL is returned.
 317  *
 318  * Note that 'sep' is able to split a string using
 319  * a multi-character separator. For example
 320  * sdssplit("foo_-_bar","_-_"); will return two
 321  * elements "foo" and "bar".
 322  *
 323  * This version of the function is binary-safe but
 324  * requires length arguments. sdssplit() is just the
 325  * same function but for zero-terminated strings.
 326  */
 327 sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) {
 328     int elements = 0, slots = 5, start = 0, j;
 329     sds *tokens;
 330
 331     if (seplen < 1 || len < 0) return NULL;
 332
 333     tokens = zmalloc(sizeof(sds)*slots);
 334     if (tokens == NULL) return NULL;
 335
 336     if (len == 0) {
 337         *count = 0;
 338         return tokens;
 339     }
 340     for (j = 0; j < (len-(seplen-1)); j++) {
 341         /* make sure there is room for the next element and the final one */
 342         if (slots < elements+2) {
 343             sds *newtokens;
 344
 345             slots *= 2;
 346             newtokens = zrealloc(tokens,sizeof(sds)*slots);
 347             if (newtokens == NULL) goto cleanup;
 348             tokens = newtokens;
 349         }
 350         /* search the separator */
 351         if ((seplen == 1 && *(s+j) == sep[0]) || (memcmp(s+j,sep,seplen) == 0)) {
 352             tokens[elements] = sdsnewlen(s+start,j-start);
 353             if (tokens[elements] == NULL) goto cleanup;
 354             elements++;
 355             start = j+seplen;
 356             j = j+seplen-1; /* skip the separator */
 357         }
 358     }
 359     /* Add the final element. We are sure there is room in the tokens array. */
 360     tokens[elements] = sdsnewlen(s+start,len-start);
 361     if (tokens[elements] == NULL) goto cleanup;
 362     elements++;
 363     *count = elements;
 364     return tokens;
 365
 366 cleanup:
 367     {
 368         int i;
 369         for (i = 0; i < elements; i++) sdsfree(tokens[i]);
 370         zfree(tokens);
 371         *count = 0;
 372         return NULL;
 373     }
 374 }
 375
 376 void sdsfreesplitres(sds *tokens, int count) {
 377     if (!tokens) return;
 378     while(count--)
 379         sdsfree(tokens[count]);
 380     zfree(tokens);
 381 }
 382
 383 sds sdsfromlonglong(long long value) {
 384     char buf[32], *p;
 385     unsigned long long v;
 386
 387     v = (value < 0) ? -value : value;
 388     p = buf+31; /* point to the last character */
 389     do {
 390         *p-- = '0'+(v%10);
 391         v /= 10;
 392     } while(v);
 393     if (value < 0) *p-- = '-';
 394     p++;
 395     return sdsnewlen(p,32-(p-buf));
 396 }
 397
 398 sds sdscatrepr(sds s, char *p, size_t len) {
 399     s = sdscatlen(s,"\"",1);
 400     while(len--) {
 401         switch(*p) {
 402         case '\\':
 403         case '"':
 404             s = sdscatprintf(s,"\\%c",*p);
 405             break;
 406         case '\n': s = sdscatlen(s,"\\n",2); break;
 407         case '\r': s = sdscatlen(s,"\\r",2); break;
 408         case '\t': s = sdscatlen(s,"\\t",2); break;
 409         case '\a': s = sdscatlen(s,"\\a",2); break;
 410         case '\b': s = sdscatlen(s,"\\b",2); break;
 411         default:
 412             if (isprint(*p))
 413                 s = sdscatprintf(s,"%c",*p);
 414             else
 415                 s = sdscatprintf(s,"\\x%02x",(unsigned char)*p);
 416             break;
 417         }
 418         p++;
 419     }
 420     return sdscatlen(s,"\"",1);
 421 }
 422
 423 /* Helper function for sdssplitargs() that returns non zero if 'c'
 424  * is a valid hex digit. */
 425 int is_hex_digit(char c) {
 426     return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') ||
 427            (c >= 'A' && c <= 'F');
 428 }
 429
 430 /* Helper function for sdssplitargs() that converts an hex digit into an
 431  * integer from 0 to 15 */
 432 int hex_digit_to_int(char c) {
 433     switch(c) {
 434     case '0': return 0;
 435     case '1': return 1;
 436     case '2': return 2;
 437     case '3': return 3;
 438     case '4': return 4;
 439     case '5': return 5;
 440     case '6': return 6;
 441     case '7': return 7;
 442     case '8': return 8;
 443     case '9': return 9;
 444     case 'a': case 'A': return 10;
 445     case 'b': case 'B': return 11;
 446     case 'c': case 'C': return 12;
 447     case 'd': case 'D': return 13;
 448     case 'e': case 'E': return 14;
 449     case 'f': case 'F': return 15;
 450     default: return 0;
 451     }
 452 }
 453
 454 /* Split a line into arguments, where every argument can be in the
 455  * following programming-language REPL-alike form:
 456  *
 457  * foo bar "newline are supported\n" and "\xff\x00otherstuff"
 458  *
 459  * The number of arguments is stored into *argc, and an array
 460  * of sds is returned. The caller should sdsfree() all the returned
 461  * strings and finally zfree() the array itself.
 462  *
 463  * Note that sdscatrepr() is able to convert back a string into
 464  * a quoted string in the same format sdssplitargs() is able to parse.
 465  */
 466 sds *sdssplitargs(char *line, int *argc) {
 467     char *p = line;
 468     char *current = NULL;
 469     char **vector = NULL;
 470
 471     *argc = 0;
 472     while(1) {
 473         /* skip blanks */
 474         while(*p && isspace(*p)) p++;
 475         if (*p) {
 476             /* get a token */
 477             int inq=0;  /* set to 1 if we are in "quotes" */
 478             int insq=0; /* set to 1 if we are in 'single quotes' */
 479             int done=0;
 480
 481             if (current == NULL) current = sdsempty();
 482             while(!done) {
 483                 if (inq) {
 484                     if (*p == '\\' && *(p+1) == 'x' &&
 485                                              is_hex_digit(*(p+2)) &&
 486                                              is_hex_digit(*(p+3)))
 487                     {
 488                         unsigned char byte;
 489
 490                         byte = (hex_digit_to_int(*(p+2))*16)+
 491                                 hex_digit_to_int(*(p+3));
 492                         current = sdscatlen(current,(char*)&byte,1);
 493                         p += 3;
 494                     } else if (*p == '\\' && *(p+1)) {
 495                         char c;
 496
 497                         p++;
 498                         switch(*p) {
 499                         case 'n': c = '\n'; break;
 500                         case 'r': c = '\r'; break;
 501                         case 't': c = '\t'; break;
 502                         case 'b': c = '\b'; break;
 503                         case 'a': c = '\a'; break;
 504                         default: c = *p; break;
 505                         }
 506                         current = sdscatlen(current,&c,1);
 507                     } else if (*p == '"') {
 508                         /* closing quote must be followed by a space or
 509                          * nothing at all. */
 510                         if (*(p+1) && !isspace(*(p+1))) goto err;
 511                         done=1;
 512                     } else if (!*p) {
 513                         /* unterminated quotes */
 514                         goto err;
 515                     } else {
 516                         current = sdscatlen(current,p,1);
 517                     }
 518                 } else if (insq) {
 519                     if (*p == '\\' && *(p+1) == '\'') {
 520                         p++;
 521                         current = sdscatlen(current,"'",1);
 522                     } else if (*p == '\'') {
 523                         /* closing quote must be followed by a space or
 524                          * nothing at all. */
 525                         if (*(p+1) && !isspace(*(p+1))) goto err;
 526                         done=1;
 527                     } else if (!*p) {
 528                         /* unterminated quotes */
 529                         goto err;
 530                     } else {
 531                         current = sdscatlen(current,p,1);
 532                     }
 533                 } else {
 534                     switch(*p) {
 535                     case ' ':
 536                     case '\n':
 537                     case '\r':
 538                     case '\t':
 539                     case '\0':
 540                         done=1;
 541                         break;
 542                     case '"':
 543                         inq=1;
 544                         break;
 545                     case '\'':
 546                         insq=1;
 547                         break;
 548                     default:
 549                         current = sdscatlen(current,p,1);
 550                         break;
 551                     }
 552                 }
 553                 if (*p) p++;
 554             }
 555             /* add the token to the vector */
 556             vector = zrealloc(vector,((*argc)+1)*sizeof(char*));
 557             vector[*argc] = current;
 558             (*argc)++;
 559             current = NULL;
 560         } else {
 561             return vector;
 562         }
 563     }
 564
 565 err:
 566     while((*argc)--)
 567         sdsfree(vector[*argc]);
 568     zfree(vector);
 569     if (current) sdsfree(current);
 570     return NULL;
 571 }
 572
 573 void sdssplitargs_free(sds *argv, int argc) {
 574     int j;
 575
 576     for (j = 0 ;j < argc; j++) sdsfree(argv[j]);
 577     zfree(argv);
 578 }
 579
 580 /* Modify the string substituting all the occurrences of the set of
 581  * characters specifed in the 'from' string to the corresponding character
 582  * in the 'to' array.
 583  *
 584  * For instance: sdsmapchars(mystring, "ho", "01", 2)
 585  * will have the effect of turning the string "hello" into "0ell1".
 586  *
 587  * The function returns the sds string pointer, that is always the same
 588  * as the input pointer since no resize is needed. */
 589 sds sdsmapchars(sds s, char *from, char *to, size_t setlen) {
 590     size_t j, i, l = sdslen(s);
 591
 592     for (j = 0; j < l; j++) {
 593         for (i = 0; i < setlen; i++) {
 594             if (s[j] == from[i]) {
 595                 s[j] = to[i];
 596                 break;
 597             }
 598         }
 599     }
 600     return s;
 601 }
 602
 603 #ifdef SDS_TEST_MAIN
 604 #include <stdio.h>
 605 #include "testhelp.h"
 606
 607 int main(void) {
 608     {
 609         struct sdshdr *sh;
 610         sds x = sdsnew("foo"), y;
 611
 612         test_cond("Create a string and obtain the length",
 613             sdslen(x) == 3 && memcmp(x,"foo\0",4) == 0)
 614
 615         sdsfree(x);
 616         x = sdsnewlen("foo",2);
 617         test_cond("Create a string with specified length",
 618             sdslen(x) == 2 && memcmp(x,"fo\0",3) == 0)
 619
 620         x = sdscat(x,"bar");
 621         test_cond("Strings concatenation",
 622             sdslen(x) == 5 && memcmp(x,"fobar\0",6) == 0);
 623
 624         x = sdscpy(x,"a");
 625         test_cond("sdscpy() against an originally longer string",
 626             sdslen(x) == 1 && memcmp(x,"a\0",2) == 0)
 627
 628         x = sdscpy(x,"xyzxxxxxxxxxxyyyyyyyyyykkkkkkkkkk");
 629         test_cond("sdscpy() against an originally shorter string",
 630             sdslen(x) == 33 &&
 631             memcmp(x,"xyzxxxxxxxxxxyyyyyyyyyykkkkkkkkkk\0",33) == 0)
 632
 633         sdsfree(x);
 634         x = sdscatprintf(sdsempty(),"%d",123);
 635         test_cond("sdscatprintf() seems working in the base case",
 636             sdslen(x) == 3 && memcmp(x,"123\0",4) ==0)
 637
 638         sdsfree(x);
 639         x = sdstrim(sdsnew("xxciaoyyy"),"xy");
 640         test_cond("sdstrim() correctly trims characters",
 641             sdslen(x) == 4 && memcmp(x,"ciao\0",5) == 0)
 642
 643         y = sdsrange(sdsdup(x),1,1);
 644         test_cond("sdsrange(...,1,1)",
 645             sdslen(y) == 1 && memcmp(y,"i\0",2) == 0)
 646
 647         sdsfree(y);
 648         y = sdsrange(sdsdup(x),1,-1);
 649         test_cond("sdsrange(...,1,-1)",
 650             sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
 651
 652         sdsfree(y);
 653         y = sdsrange(sdsdup(x),-2,-1);
 654         test_cond("sdsrange(...,-2,-1)",
 655             sdslen(y) == 2 && memcmp(y,"ao\0",3) == 0)
 656
 657         sdsfree(y);
 658         y = sdsrange(sdsdup(x),2,1);
 659         test_cond("sdsrange(...,2,1)",
 660             sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
 661
 662         sdsfree(y);
 663         y = sdsrange(sdsdup(x),1,100);
 664         test_cond("sdsrange(...,1,100)",
 665             sdslen(y) == 3 && memcmp(y,"iao\0",4) == 0)
 666
 667         sdsfree(y);
 668         y = sdsrange(sdsdup(x),100,100);
 669         test_cond("sdsrange(...,100,100)",
 670             sdslen(y) == 0 && memcmp(y,"\0",1) == 0)
 671
 672         sdsfree(y);
 673         sdsfree(x);
 674         x = sdsnew("foo");
 675         y = sdsnew("foa");
 676         test_cond("sdscmp(foo,foa)", sdscmp(x,y) > 0)
 677
 678         sdsfree(y);
 679         sdsfree(x);
 680         x = sdsnew("bar");
 681         y = sdsnew("bar");
 682         test_cond("sdscmp(bar,bar)", sdscmp(x,y) == 0)
 683
 684         sdsfree(y);
 685         sdsfree(x);
 686         x = sdsnew("aar");
 687         y = sdsnew("bar");
 688         test_cond("sdscmp(bar,bar)", sdscmp(x,y) < 0)
 689
 690         {
 691             int oldfree;
 692
 693             sdsfree(x);
 694             x = sdsnew("0");
 695             sh = (void*) (x-(sizeof(struct sdshdr)));
 696             test_cond("sdsnew() free/len buffers", sh->len == 1 && sh->free == 0);
 697             x = sdsMakeRoomFor(x,1);
 698             sh = (void*) (x-(sizeof(struct sdshdr)));
 699             test_cond("sdsMakeRoomFor()", sh->len == 1 && sh->free > 0);
 700             oldfree = sh->free;
 701             x[1] = '1';
 702             sdsIncrLen(x,1);
 703             test_cond("sdsIncrLen() -- content", x[0] == '0' && x[1] == '1');
 704             test_cond("sdsIncrLen() -- len", sh->len == 2);
 705             test_cond("sdsIncrLen() -- free", sh->free == oldfree-1);
 706         }
 707     }
 708     test_report()
 709     return 0;
 710 }
 711 #endif