X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/ac1f6fd07a15ac7a14f27b8a5f4b5fb3dc6cf8ac..3f7ad83398f66dfd7a4beb1b5bf610b499f6b942:/src/sds.c diff --git a/src/sds.c b/src/sds.c index 77052966..bc6aa6b2 100644 --- a/src/sds.c +++ b/src/sds.c @@ -26,28 +26,16 @@ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. - * - * History: - * - * - 22 March 2011: History section created on top of sds.c - * - 22 March 2011: Fixed a problem with "\xab" escapes convertion in - * function sdssplitargs(). */ -#define SDS_ABORT_ON_OOM - #include #include #include #include +#include #include "sds.h" #include "zmalloc.h" -static void sdsOomAbort(void) { - fprintf(stderr,"SDS: Out Of Memory (SDS_ABORT_ON_OOM defined)\n"); - abort(); -} - sds sdsnewlen(const void *init, size_t initlen) { struct sdshdr *sh; @@ -56,11 +44,7 @@ sds sdsnewlen(const void *init, size_t initlen) { } else { sh = zcalloc(sizeof(struct sdshdr)+initlen+1); } -#ifdef SDS_ABORT_ON_OOM - if (sh == NULL) sdsOomAbort(); -#else if (sh == NULL) return NULL; -#endif sh->len = initlen; sh->free = 0; if (initlen && init) @@ -101,7 +85,13 @@ void sdsclear(sds s) { sh->buf[0] = '\0'; } -static sds sdsMakeRoomFor(sds s, size_t addlen) { +/* Enlarge the free space at the end of the sds string so that the caller + * is sure that after calling this function can overwrite up to addlen + * bytes after the end of the string, plus one more byte for nul term. + * + * Note: this does not change the *size* of the sds string as returned + * by sdslen(), but only the free buffer space we have. */ +sds sdsMakeRoomFor(sds s, size_t addlen) { struct sdshdr *sh, *newsh; size_t free = sdsavail(s); size_t len, newlen; @@ -109,18 +99,67 @@ static sds sdsMakeRoomFor(sds s, size_t addlen) { if (free >= addlen) return s; len = sdslen(s); sh = (void*) (s-(sizeof(struct sdshdr))); - newlen = (len+addlen)*2; + newlen = (len+addlen); + if (newlen < SDS_MAX_PREALLOC) + newlen *= 2; + else + newlen += SDS_MAX_PREALLOC; newsh = zrealloc(sh, sizeof(struct sdshdr)+newlen+1); -#ifdef SDS_ABORT_ON_OOM - if (newsh == NULL) sdsOomAbort(); -#else if (newsh == NULL) return NULL; -#endif newsh->free = newlen - len; return newsh->buf; } +/* Reallocate the sds string so that it has no free space at the end. The + * contained string remains not altered, but next concatenation operations + * will require a reallocation. */ +sds sdsRemoveFreeSpace(sds s) { + struct sdshdr *sh; + + sh = (void*) (s-(sizeof(struct sdshdr))); + sh = zrealloc(sh, sizeof(struct sdshdr)+sh->len+1); + sh->free = 0; + return sh->buf; +} + +size_t sdsAllocSize(sds s) { + struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr))); + + return sizeof(*sh)+sh->len+sh->free+1; +} + +/* Increment the sds length and decrements the left free space at the + * end of the string accordingly to 'incr'. Also set the null term + * in the new end of the string. + * + * This function is used in order to fix the string length after the + * user calls sdsMakeRoomFor(), writes something after the end of + * the current string, and finally needs to set the new length. + * + * Note: it is possible to use a negative increment in order to + * right-trim the string. + * + * Using sdsIncrLen() and sdsMakeRoomFor() it is possible to mount the + * following schema to cat bytes coming from the kerenl to the end of an + * sds string new things without copying into an intermediate buffer: + * + * oldlen = sdslen(s); + * s = sdsMakeRoomFor(s, BUFFER_SIZE); + * nread = read(fd, s+oldlen, BUFFER_SIZE); + * ... check for nread <= 0 and handle it ... + * sdsIncrLen(s, nhread); + */ +void sdsIncrLen(sds s, int incr) { + struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr))); + + assert(sh->free >= incr); + sh->len += incr; + sh->free -= incr; + assert(sh->free >= 0); + s[sh->len] = '\0'; +} + /* Grow the sds to have the specified length. Bytes that were not part of * the original length of the sds will be set to zero. */ sds sdsgrowzero(sds s, size_t len) { @@ -158,6 +197,10 @@ sds sdscat(sds s, char *t) { return sdscatlen(s, t, strlen(t)); } +sds sdscatsds(sds s, sds t) { + return sdscatlen(s, t, sdslen(t)); +} + sds sdscpylen(sds s, char *t, size_t len) { struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr))); size_t totlen = sh->free+sh->len; @@ -186,11 +229,7 @@ sds sdscatvprintf(sds s, const char *fmt, va_list ap) { while(1) { buf = zmalloc(buflen); -#ifdef SDS_ABORT_ON_OOM - if (buf == NULL) sdsOomAbort(); -#else if (buf == NULL) return NULL; -#endif buf[buflen-2] = '\0'; va_copy(cpy,ap); vsnprintf(buf, buflen, fmt, cpy); @@ -310,11 +349,7 @@ sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) { if (seplen < 1 || len < 0) return NULL; tokens = zmalloc(sizeof(sds)*slots); -#ifdef SDS_ABORT_ON_OOM - if (tokens == NULL) sdsOomAbort(); -#else if (tokens == NULL) return NULL; -#endif if (len == 0) { *count = 0; @@ -327,25 +362,13 @@ sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) { slots *= 2; newtokens = zrealloc(tokens,sizeof(sds)*slots); - if (newtokens == NULL) { -#ifdef SDS_ABORT_ON_OOM - sdsOomAbort(); -#else - goto cleanup; -#endif - } + if (newtokens == NULL) goto cleanup; tokens = newtokens; } /* search the separator */ if ((seplen == 1 && *(s+j) == sep[0]) || (memcmp(s+j,sep,seplen) == 0)) { tokens[elements] = sdsnewlen(s+start,j-start); - if (tokens[elements] == NULL) { -#ifdef SDS_ABORT_ON_OOM - sdsOomAbort(); -#else - goto cleanup; -#endif - } + if (tokens[elements] == NULL) goto cleanup; elements++; start = j+seplen; j = j+seplen-1; /* skip the separator */ @@ -353,18 +376,11 @@ sds *sdssplitlen(char *s, int len, char *sep, int seplen, int *count) { } /* Add the final element. We are sure there is room in the tokens array. */ tokens[elements] = sdsnewlen(s+start,len-start); - if (tokens[elements] == NULL) { -#ifdef SDS_ABORT_ON_OOM - sdsOomAbort(); -#else - goto cleanup; -#endif - } + if (tokens[elements] == NULL) goto cleanup; elements++; *count = elements; return tokens; -#ifndef SDS_ABORT_ON_OOM cleanup: { int i; @@ -373,7 +389,6 @@ cleanup: *count = 0; return NULL; } -#endif } void sdsfreesplitres(sds *tokens, int count) { @@ -477,7 +492,8 @@ sds *sdssplitargs(char *line, int *argc) { while(*p && isspace(*p)) p++; if (*p) { /* get a token */ - int inq=0; /* set to 1 if we are in "quotes" */ + int inq=0; /* set to 1 if we are in "quotes" */ + int insq=0; /* set to 1 if we are in 'single quotes' */ int done=0; if (current == NULL) current = sdsempty(); @@ -507,7 +523,23 @@ sds *sdssplitargs(char *line, int *argc) { } current = sdscatlen(current,&c,1); } else if (*p == '"') { - /* closing quote must be followed by a space */ + /* closing quote must be followed by a space or + * nothing at all. */ + if (*(p+1) && !isspace(*(p+1))) goto err; + done=1; + } else if (!*p) { + /* unterminated quotes */ + goto err; + } else { + current = sdscatlen(current,p,1); + } + } else if (insq) { + if (*p == '\\' && *(p+1) == '\'') { + p++; + current = sdscatlen(current,"'",1); + } else if (*p == '\'') { + /* closing quote must be followed by a space or + * nothing at all. */ if (*(p+1) && !isspace(*(p+1))) goto err; done=1; } else if (!*p) { @@ -528,6 +560,9 @@ sds *sdssplitargs(char *line, int *argc) { case '"': inq=1; break; + case '\'': + insq=1; + break; default: current = sdscatlen(current,p,1); break; @@ -589,6 +624,7 @@ sds sdsmapchars(sds s, char *from, char *to, size_t setlen) { int main(void) { { + struct sdshdr *sh; sds x = sdsnew("foo"), y; test_cond("Create a string and obtain the length", @@ -668,7 +704,26 @@ int main(void) { x = sdsnew("aar"); y = sdsnew("bar"); test_cond("sdscmp(bar,bar)", sdscmp(x,y) < 0) + + { + int oldfree; + + sdsfree(x); + x = sdsnew("0"); + sh = (void*) (x-(sizeof(struct sdshdr))); + test_cond("sdsnew() free/len buffers", sh->len == 1 && sh->free == 0); + x = sdsMakeRoomFor(x,1); + sh = (void*) (x-(sizeof(struct sdshdr))); + test_cond("sdsMakeRoomFor()", sh->len == 1 && sh->free > 0); + oldfree = sh->free; + x[1] = '1'; + sdsIncrLen(x,1); + test_cond("sdsIncrLen() -- content", x[0] == '0' && x[1] == '1'); + test_cond("sdsIncrLen() -- len", sh->len == 2); + test_cond("sdsIncrLen() -- free", sh->free == oldfree-1); + } } test_report() + return 0; } #endif