fix processing of large bulks (above 2GB)

- protocol parsing (processMultibulkBuffer) was limitted to 32big positions in the buffer
  readQueryFromClient potential overflow
- rioWriteBulkCount used int, although rioWriteBulkString gave it size_t
- several places in sds.c that used int for string length or index.
- bugfix in RM_SaveAuxField (return was 1 or -1 and not length)
- RM_SaveStringBuffer was limitted to 32bit length

src/sds.c

@@ -175,7 +175,7 @@ void sdsfree(sds s) {
  * the output will be "6" as the string was modified but the logical length
  * remains 6 bytes. */
 void sdsupdatelen(sds s) {
-    int reallen = strlen(s);
+    size_t reallen = strlen(s);
     sdssetlen(s, reallen);
 }
 
@@ -319,7 +319,7 @@ void *sdsAllocPtr(sds s) {
  * ... check for nread <= 0 and handle it ...
  * sdsIncrLen(s, nread);
  */
-void sdsIncrLen(sds s, int incr) {
+void sdsIncrLen(sds s, ssize_t incr) {
     unsigned char flags = s[-1];
     size_t len;
     switch(flags&SDS_TYPE_MASK) {
@@ -589,7 +589,7 @@ sds sdscatprintf(sds s, const char *fmt, ...) {
 sds sdscatfmt(sds s, char const *fmt, ...) {
     size_t initlen = sdslen(s);
     const char *f = fmt;
-    int i;
+    long i;
     va_list ap;
 
     va_start(ap,fmt);
@@ -721,7 +721,7 @@ sds sdstrim(sds s, const char *cset) {
  * s = sdsnew("Hello World");
  * sdsrange(s,1,-1); => "ello World"
  */
-void sdsrange(sds s, int start, int end) {
+void sdsrange(sds s, ssize_t start, ssize_t end) {
     size_t newlen, len = sdslen(s);
 
     if (len == 0) return;
@@ -735,9 +735,9 @@ void sdsrange(sds s, int start, int end) {
     }
     newlen = (start > end) ? 0 : (end-start)+1;
     if (newlen != 0) {
-        if (start >= (signed)len) {
+        if (start >= (ssize_t)len) {
             newlen = 0;
-        } else if (end >= (signed)len) {
+        } else if (end >= (ssize_t)len) {
             end = len-1;
             newlen = (start > end) ? 0 : (end-start)+1;
         }
@@ -751,14 +751,14 @@ void sdsrange(sds s, int start, int end) {
 
 /* Apply tolower() to every character of the sds string 's'. */
 void sdstolower(sds s) {
-    int len = sdslen(s), j;
+    size_t len = sdslen(s), j;
 
     for (j = 0; j < len; j++) s[j] = tolower(s[j]);
 }
 
 /* Apply toupper() to every character of the sds string 's'. */
 void sdstoupper(sds s) {
-    int len = sdslen(s), j;
+    size_t len = sdslen(s), j;
 
     for (j = 0; j < len; j++) s[j] = toupper(s[j]);
 }
@@ -782,7 +782,7 @@ int sdscmp(const sds s1, const sds s2) {
     l2 = sdslen(s2);
     minlen = (l1 < l2) ? l1 : l2;
     cmp = memcmp(s1,s2,minlen);
-    if (cmp == 0) return l1-l2;
+    if (cmp == 0) return l1>l2? 1: (l1<l2? -1: 0);
     return cmp;
 }
 
@@ -802,8 +802,9 @@ int sdscmp(const sds s1, const sds s2) {
  * requires length arguments. sdssplit() is just the
  * same function but for zero-terminated strings.
  */
-sds *sdssplitlen(const char *s, int len, const char *sep, int seplen, int *count) {
-    int elements = 0, slots = 5, start = 0, j;
+sds *sdssplitlen(const char *s, ssize_t len, const char *sep, int seplen, int *count) {
+    int elements = 0, slots = 5;
+    long start = 0, j;
     sds *tokens;
 
     if (seplen < 1 || len < 0) return NULL;