Fixed sdssplitargs() handling of hex-style escapes.

src/sds.c

@@ -26,6 +26,12 @@
  * 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
@@ -416,6 +422,37 @@ sds sdscatrepr(sds s, char *p, size_t len) {
     return sdscatlen(s,"\"",1);
 }
 
+/* Helper function for sdssplitargs() that returns non zero if 'c'
+ * is a valid hex digit. */
+int is_hex_digit(char c) {
+    return (c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') ||
+           (c >= 'A' && c <= 'F');
+}
+
+/* Helper function for sdssplitargs() that converts an hex digit into an
+ * integer from 0 to 15 */
+int hex_digit_to_int(char c) {
+    switch(c) {
+    case '0': return 0;
+    case '1': return 1;
+    case '2': return 2;
+    case '3': return 3;
+    case '4': return 4;
+    case '5': return 5;
+    case '6': return 6;
+    case '7': return 7;
+    case '8': return 8;
+    case '9': return 9;
+    case 'a': case 'A': return 10;
+    case 'b': case 'B': return 11;
+    case 'c': case 'C': return 12;
+    case 'd': case 'D': return 13;
+    case 'e': case 'E': return 14;
+    case 'f': case 'F': return 15;
+    default: return 0;
+    }
+}
+
 /* Split a line into arguments, where every argument can be in the
  * following programming-language REPL-alike form:
  *
@@ -445,7 +482,17 @@ sds *sdssplitargs(char *line, int *argc) {
             if (current == NULL) current = sdsempty();
             while(!done) {
                 if (inq) {
-                    if (*p == '\\' && *(p+1)) {
+                    if (*p == '\\' && *(p+1) == 'x' &&
+                                             is_hex_digit(*(p+2)) &&
+                                             is_hex_digit(*(p+3)))
+                    {
+                        unsigned char byte;
+
+                        byte = (hex_digit_to_int(*(p+2))*16)+
+                                hex_digit_to_int(*(p+3));
+                        current = sdscatlen(current,(char*)&byte,1);
+                        p += 3;
+                    } else if (*p == '\\' && *(p+1)) {
                         char c;
 
                         p++;