rigol-ds: Fix a couple of compile warnings.

diff --git a/hardware/rigol-ds/protocol.c b/hardware/rigol-ds/protocol.c
index 162ff829539abe7c2bf497ab34f419b5380b3fdb..3e6a5bef694c94c6b8d8247c4ee53e95072b1011 100644 (file)
--- a/hardware/rigol-ds/protocol.c
+++ b/hardware/rigol-ds/protocol.c
@@ -422,18 +422,18 @@ static int rigol_ds_read_header(struct sr_dev_inst *sdi)
        struct sr_scpi_dev_inst *scpi = sdi->conn;
        struct dev_context *devc = sdi->priv;
        char *buf = (char *) devc->buffer;
-       int len;
-       int tmp;
+       size_t header_length;
+       int ret;
 
        /* Try to read the hashsign and length digit. */
        if (devc->num_header_bytes < 2) {
-               tmp = sr_scpi_read_data(scpi, buf + devc->num_header_bytes,
+               ret = sr_scpi_read_data(scpi, buf + devc->num_header_bytes,
                                2 - devc->num_header_bytes);
-               if (tmp < 0) {
+               if (ret < 0) {
                        sr_err("Read error while reading data header.");
                        return SR_ERR;
                }
-               devc->num_header_bytes += tmp;
+               devc->num_header_bytes += ret;
        }
 
        if (devc->num_header_bytes < 2)
@@ -444,33 +444,33 @@ static int rigol_ds_read_header(struct sr_dev_inst *sdi)
                return SR_ERR;
        }
 
-       len = buf[1] - '0';
+       header_length = 2 + buf[1] - '0';
 
        /* Try to read the length. */
-       if (devc->num_header_bytes < 2 + len) {
-               tmp = sr_scpi_read_data(scpi, buf + devc->num_header_bytes,
-                               2 + len - devc->num_header_bytes);
-               if (tmp < 0) {
+       if (devc->num_header_bytes < header_length) {
+               ret = sr_scpi_read_data(scpi, buf + devc->num_header_bytes,
+                               header_length - devc->num_header_bytes);
+               if (ret < 0) {
                        sr_err("Read error while reading data header.");
                        return SR_ERR;
                }
-               devc->num_header_bytes += tmp;
+               devc->num_header_bytes += ret;
        }
 
-       if (devc->num_header_bytes < 2 + len)
+       if (devc->num_header_bytes < header_length)
                return 0;
 
        /* Read the data length. */
-       buf[2 + len] = '\0';
+       buf[header_length] = '\0';
 
-       if (parse_int(buf + 2, &len) != SR_OK) {
+       if (parse_int(buf + 2, &ret) != SR_OK) {
                sr_err("Received invalid data block length '%s'.", buf + 2);
                return -1;
        }
 
-       sr_dbg("Received data block header: '%s' -> block length %d", buf, len);
+       sr_dbg("Received data block header: '%s' -> block length %d", buf, ret);
 
-       return len;
+       return ret;
 }
 
 SR_PRIV int rigol_ds_receive(int fd, int revents, void *cb_data)