drivers: Fix locale dependent string to float conversion

[libsigrok.git] / src / dmm / metex14.c

diff --git a/src/dmm/metex14.c b/src/dmm/metex14.c
index a6e2a317369170ecfd7a912bc9122f453e42bf68..0dd5d2edc8602dada2c4c24666bf818f239d46c2 100644 (file)
--- a/src/dmm/metex14.c
+++ b/src/dmm/metex14.c
@@ -14,8 +14,7 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 /**
@@ -43,9 +42,9 @@
 
 /** Parse value from buf, byte 2-8. */
 static int parse_value(const uint8_t *buf, struct metex14_info *info,
-                       float *result)
+                       float *result, int *exponent)
 {
-       int i, is_ol, cnt;
+       int i, is_ol, cnt, dot_pos;
        char valstr[7 + 1];
 
        /* Strip all spaces from bytes 2-8. */
@@ -87,7 +86,13 @@ static int parse_value(const uint8_t *buf, struct metex14_info *info,
                return SR_OK;
 
        /* Bytes 2-8: Sign, value (up to 5 digits) and decimal point */
-       sscanf((const char *)&valstr, "%f", result);
+       sr_atof_ascii((const char *)&valstr, result);
+
+       dot_pos = strcspn(valstr, ".");
+       if (dot_pos < cnt)
+               *exponent = -(cnt - dot_pos - 1);
+       else
+               *exponent = 0;
 
        sr_spew("The display value is %f.", *result);
 
@@ -147,17 +152,17 @@ static void parse_flags(const char *buf, struct metex14_info *info)
                info->is_unitless = TRUE;
 
        /* Bytes 0-1: Measurement mode, except AC/DC */
-       info->is_resistance  = !strncmp(buf, "OH", 2) ||
+       info->is_resistance = !strncmp(buf, "OH", 2) ||
                (!strncmp(buf, "  ", 2) && info->is_ohm);
-       info->is_capacity    = !strncmp(buf, "CA", 2) ||
+       info->is_capacity = !strncmp(buf, "CA", 2) ||
                (!strncmp(buf, "  ", 2) && info->is_farad);
        info->is_temperature = !strncmp(buf, "TE", 2);
-       info->is_diode       = !strncmp(buf, "DI", 2) ||
+       info->is_diode = !strncmp(buf, "DI", 2) ||
                (!strncmp(buf, "  ", 2) && info->is_volt && info->is_milli);
-       info->is_frequency   = !strncmp(buf, "FR", 2) ||
+       info->is_frequency = !strncmp(buf, "FR", 2) ||
                (!strncmp(buf, "  ", 2) && info->is_hertz);
-       info->is_gain        = !strncmp(buf, "DB", 2);
-       info->is_hfe         = !strncmp(buf, "HF", 2) ||
+       info->is_gain = !strncmp(buf, "DB", 2);
+       info->is_hfe = !strncmp(buf, "HF", 2) ||
                (!strncmp(buf, "  ", 2) && !info->is_volt && !info->is_ohm &&
                 !info->is_logic && !info->is_farad && !info->is_hertz);
        /*
@@ -171,21 +176,24 @@ static void parse_flags(const char *buf, struct metex14_info *info)
 }
 
 static void handle_flags(struct sr_datafeed_analog *analog, float *floatval,
-                        const struct metex14_info *info)
+                        int *exponent, const struct metex14_info *info)
 {
+       int factor = 0;
        /* Factors */
        if (info->is_pico)
-               *floatval /= 1000000000000ULL;
+               factor -= 12;
        if (info->is_nano)
-               *floatval /= 1000000000;
+               factor -= 9;
        if (info->is_micro)
-               *floatval /= 1000000;
+               factor -= 6;
        if (info->is_milli)
-               *floatval /= 1000;
+               factor -= 3;
        if (info->is_kilo)
-               *floatval *= 1000;
+               factor += 3;
        if (info->is_mega)
-               *floatval *= 1000000;
+               factor += 6;
+       *floatval *= powf(10, factor);
+       *exponent += factor;
 
        /* Measurement modes */
        if (info->is_volt) {
@@ -285,7 +293,7 @@ SR_PRIV int sr_metex14_packet_request(struct sr_serial_dev_inst *serial)
 
        sr_spew("Requesting DMM packet.");
 
-       return (serial_write_nonblocking(serial, &wbuf, 1) == 1) ? SR_OK : SR_ERR;
+       return serial_write_blocking(serial, &wbuf, 1, 0);
 }
 #endif
 
@@ -323,7 +331,7 @@ SR_PRIV gboolean sr_metex14_packet_valid(const uint8_t *buf)
 SR_PRIV int sr_metex14_parse(const uint8_t *buf, float *floatval,
                             struct sr_datafeed_analog *analog, void *info)
 {
-       int ret;
+       int ret, exponent = 0;
        struct metex14_info *info_local;
 
        info_local = (struct metex14_info *)info;
@@ -333,13 +341,16 @@ SR_PRIV int sr_metex14_parse(const uint8_t *buf, float *floatval,
 
        memset(info_local, 0x00, sizeof(struct metex14_info));
 
-       if ((ret = parse_value(buf, info_local, floatval)) != SR_OK) {
+       if ((ret = parse_value(buf, info_local, floatval, &exponent)) != SR_OK) {
                sr_dbg("Error parsing value: %d.", ret);
                return ret;
        }
 
        parse_flags((const char *)buf, info_local);
-       handle_flags(analog, floatval, info_local);
+       handle_flags(analog, floatval, &exponent, info_local);
+
+       analog->encoding->digits = -exponent;
+       analog->spec->spec_digits = -exponent;
 
        return SR_OK;
 }