Make sr_analog_*_to_string() functions allocate the necessary buffers.

diff --git a/include/libsigrok/proto.h b/include/libsigrok/proto.h
index e69346057c10efea9068ca41203ad5b2890ef840..7770e175872bef09932e1150b983345e7551d6fa 100644 (file)
--- a/include/libsigrok/proto.h
+++ b/include/libsigrok/proto.h
@@ -30,10 +30,9 @@
 
 SR_API int sr_analog_to_float(const struct sr_datafeed_analog2 *analog,
                float *buf);
-SR_API int sr_analog_float_to_string(float value, int digits, char *outbuf,
-               int bufsize);
+SR_API int sr_analog_float_to_string(float value, int digits, char **result);
 SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
-               char *outbuf, int bufsize);
+               char **result);
 
 /*--- backend.c -------------------------------------------------------------*/
 

diff --git a/src/analog.c b/src/analog.c
index 4fd6a6f9a4410d06d0152e789b31bf662680ee6c..fba7830f22972151f4f616f4dcea81e9e8ae05f8 100644 (file)
--- a/src/analog.c
+++ b/src/analog.c
@@ -165,25 +165,26 @@ SR_API int sr_analog_to_float(const struct sr_datafeed_analog2 *analog,
  *
  * @param value The value to convert.
  * @param digits Number of digits after the decimal point to print.
- * @param outbuf Buffer in which the resulting string will be placed.
- * @param bufsize Size of the buffer in bytes.
+ * @param result Pointer to store result.
+ *
+ * The string is allocated by the function and must be freed by the caller
+ * after use by calling g_free().
  *
  * @retval SR_OK
  *
  * @since 0.4.0
  */
-SR_API int sr_analog_float_to_string(float value, int digits, char *outbuf,
-               int bufsize)
+SR_API int sr_analog_float_to_string(float value, int digits, char **result)
 {
        int cnt, i;
 
        /* This produces at least one too many digits */
-       snprintf(outbuf, bufsize, "%.*f", digits, value);
-       for (i = 0, cnt = 0; outbuf[i] && i < bufsize; i++) {
-               if (isdigit(outbuf[i++]))
+       *result = g_strdup_printf("%.*f", digits, value);
+       for (i = 0, cnt = 0; *result[i]; i++) {
+               if (isdigit(*result[i++]))
                        cnt++;
                if (cnt == digits) {
-                       outbuf[i] = 0;
+                       *result[i] = 0;
                        break;
                }
        }
@@ -195,33 +196,35 @@ SR_API int sr_analog_float_to_string(float value, int digits, char *outbuf,
  * Convert the unit/MQ/MQ flags in the analog struct to a string.
  *
  * @param analog Struct containing the unit, MQ and MQ flags.
- * @param outbuf Buffer in which the resulting string will be placed.
- * @param bufsize Size of the buffer in bytes.
+ * @param result Pointer to store result.
+ *
+ * The string is allocated by the function and must be freed by the caller
+ * after use by calling g_free().
  *
  * @retval SR_OK
  *
  * @since 0.4.0
  */
 SR_API int sr_analog_unit_to_string(const struct sr_datafeed_analog2 *analog,
-               char *outbuf, int bufsize)
+               char **result)
 {
-       int len, i;
+       int i;
+       GString *buf = g_string_new(NULL);
 
-       outbuf[0] = 0;
        for (i = 0; unit_strings[i].value; i++) {
                if (analog->meaning->unit == unit_strings[i].value) {
-                       strncpy(outbuf, unit_strings[i].str, bufsize);
+                       g_string_assign(buf, unit_strings[i].str);
                        break;
                }
        }
 
        /* More than one MQ flag may apply. */
-       for (i = 0; mq_strings[i].value; i++) {
-               if (analog->meaning->mqflags & mq_strings[i].value) {
-                       len = strlen(outbuf);
-                       strncat(outbuf + len, mq_strings[i].str, bufsize - len);
-               }
-       }
+       for (i = 0; mq_strings[i].value; i++)
+               if (analog->meaning->mqflags & mq_strings[i].value)
+                       g_string_append(buf, mq_strings[i].str);
+
+       *result = buf->str;
+       g_string_free(buf, FALSE);
 
        return SR_OK;
 }

diff --git a/src/output/analog.c b/src/output/analog.c
index 16ae0bd32f620453ce1bd85a397fb13551bea1be..77cf8b1074755f0888417d221a3e7e5dc10ee35c 100644 (file)
--- a/src/output/analog.c
+++ b/src/output/analog.c
@@ -241,7 +241,7 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
        float *fdata;
        unsigned int i;
        int num_channels, c, ret, si, digits;
-       char number[32], suffix[32];
+       char *number, *suffix;
 
        *out = NULL;
        if (!o || !o->sdi)
@@ -285,20 +285,22 @@ static int receive(const struct sr_output *o, const struct sr_datafeed_packet *p
                        /* TODO we don't know how to print by number of bits yet. */
                        digits = 6;
                }
-               sr_analog_unit_to_string(analog2, suffix, sizeof(suffix));
+               sr_analog_unit_to_string(analog2, &suffix);
                num_channels = g_slist_length(analog2->meaning->channels);
                for (i = 0; i < analog2->num_samples; i++) {
                        for (l = analog2->meaning->channels, c = 0; l; l = l->next, c++) {
                                ch = l->data;
                                g_string_append_printf(*out, "%s: ", ch->name);
                                sr_analog_float_to_string(fdata[i * num_channels + c],
-                                               digits, number, sizeof(number));
+                                               digits, &number);
                                g_string_append(*out, number);
+                               g_free(number);
                                g_string_append(*out, " ");
                                g_string_append(*out, suffix);
                                g_string_append(*out, "\n");
                        }
                }
+               g_free(suffix);
                break;
        }