#include <stdlib.h>
#include <string.h>
#include <ctype.h>
+#include <assert.h>
#include "sds.h"
#include "zmalloc.h"
sh->len = reallen;
}
-static sds sdsMakeRoomFor(sds s, size_t addlen) {
+void sdsclear(sds s) {
+ struct sdshdr *sh = (void*) (s-(sizeof(struct sdshdr)));
+ sh->free += sh->len;
+ sh->len = 0;
+ sh->buf[0] = '\0';
+}
+
+/* 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;
return newsh->buf;
}
+/* 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) {
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();
}
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) {
case '"':
inq=1;
break;
+ case '\'':
+ insq=1;
+ break;
default:
current = sdscatlen(current,p,1);
break;
zfree(argv);
}
+/* Modify the string substituting all the occurrences of the set of
+ * characters specifed in the 'from' string to the corresponding character
+ * in the 'to' array.
+ *
+ * For instance: sdsmapchars(mystring, "ho", "01", 2)
+ * will have the effect of turning the string "hello" into "0ell1".
+ *
+ * The function returns the sds string pointer, that is always the same
+ * as the input pointer since no resize is needed. */
+sds sdsmapchars(sds s, char *from, char *to, size_t setlen) {
+ size_t j, i, l = sdslen(s);
+
+ for (j = 0; j < l; j++) {
+ for (i = 0; i < setlen; i++) {
+ if (s[j] == from[i]) {
+ s[j] = to[i];
+ break;
+ }
+ }
+ }
+ return s;
+}
+
#ifdef SDS_TEST_MAIN
#include <stdio.h>
#include "testhelp.h"
int main(void) {
{
+ struct sdshdr *sh;
sds x = sdsnew("foo"), y;
test_cond("Create a string and obtain the length",
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
projects / redis.git / blobdiff