sr: sr_parse_triggerstring docs/improvements.

[libsigrok.git] / strutil.c

diff --git a/strutil.c b/strutil.c
index cb84e57f9c106cfbdf1b314a85b364c685de138e..014c2c2ce16538dbacc1d72bd7276fb73f9c04c1 100644 (file)
--- a/strutil.c
+++ b/strutil.c
@@ -27,7 +27,8 @@
 /**
  * Convert a numeric samplerate value to its "natural" string representation.
  *
- * E.g. a value of 3000000 would be converted to "3 MHz", 20000 to "20 kHz".
+ * E.g. a value of 3000000 would be converted to "3 MHz", 20000 to "20 kHz",
+ * 31500 would become "31.5 kHz".
  *
  * @param samplerate The samplerate in Hz.
  *
@@ -38,26 +39,30 @@
 SR_API char *sr_samplerate_string(uint64_t samplerate)
 {
        char *o;
-       int r;
+       uint64_t s = samplerate;
 
-       /* Allocate enough for a uint64_t as string + " GHz". */
-       if (!(o = g_try_malloc0(30 + 1))) {
-               sr_err("strutil: %s: o malloc failed", __func__);
-               return NULL;
+       if ((s >= SR_GHZ(1)) && (s % SR_GHZ(1) == 0)) {
+               o = g_strdup_printf("%" PRIu64 " GHz", s / SR_GHZ(1));
+       } else if ((s >= SR_GHZ(1)) && (s % SR_GHZ(1) != 0)) {
+               o = g_strdup_printf("%" PRIu64 ".%" PRIu64 " GHz",
+                                   s / SR_GHZ(1), s % SR_GHZ(1));
+       } else if ((s >= SR_MHZ(1)) && (s % SR_MHZ(1) == 0)) {
+               o = g_strdup_printf("%" PRIu64 " MHz", s / SR_MHZ(1));
+       } else if ((s >= SR_MHZ(1)) && (s % SR_MHZ(1) != 0)) {
+               o = g_strdup_printf("%" PRIu64 ".%" PRIu64 " MHz",
+                                   s / SR_MHZ(1), s % SR_MHZ(1));
+       } else if ((s >= SR_KHZ(1)) && (s % SR_KHZ(1) == 0)) {
+               o = g_strdup_printf("%" PRIu64 " kHz", s / SR_KHZ(1));
+       } else if ((s >= SR_KHZ(1)) && (s % SR_KHZ(1) != 0)) {
+               o = g_strdup_printf("%" PRIu64 ".%" PRIu64 " kHz",
+                                   s / SR_KHZ(1), s % SR_KHZ(1));
+       } else {
+               o = g_strdup_printf("%" PRIu64 " Hz", s);
        }
 
-       if (samplerate >= SR_GHZ(1))
-               r = snprintf(o, 30, "%" PRIu64 " GHz", samplerate / 1000000000);
-       else if (samplerate >= SR_MHZ(1))
-               r = snprintf(o, 30, "%" PRIu64 " MHz", samplerate / 1000000);
-       else if (samplerate >= SR_KHZ(1))
-               r = snprintf(o, 30, "%" PRIu64 " kHz", samplerate / 1000);
-       else
-               r = snprintf(o, 30, "%" PRIu64 " Hz", samplerate);
-
-       if (r < 0) {
-               /* Something went wrong... */
-               g_free(o);
+       if (!o) {
+               sr_err("strutil: %s: Error creating samplerate string.",
+                      __func__);
                return NULL;
        }
 
@@ -106,12 +111,25 @@ SR_API char *sr_period_string(uint64_t frequency)
 }
 
 /**
- * TODO
+ * Parse a trigger specification string.
  *
- * @param dev TODO
- * @param triggerstring TODO
+ * @param dev The device for which the trigger specification is intended.
+ * @param triggerstring The string containing the trigger specification for
+ *        one or more probes of this device. Entries for multiple probes are
+ *        comma-separated. Triggers are specified in the form key=value,
+ *        where the key is a probe number (or probe name) and the value is
+ *        the requested trigger type. Valid trigger types currently
+ *        include 'r' (rising edge), 'f' (falling edge), 'c' (any pin value
+ *        change), '0' (low value), or '1' (high value).
+ *        Example: "1=r,sck=f,miso=0,7=c"
  *
- * @return TODO
+ * @return Pointer to a list of trigger types (strings), or NULL upon errors.
+ *         The pointer list (if non-NULL) has as many entries as the
+ *         respective device has probes (all physically available probes,
+ *         not just enabled ones). Entries of the list which don't have
+ *         a trigger value set in 'triggerstring' are NULL, the other entries
+ *         contain the respective trigger type which is requested for the
+ *         respective probe (e.g. "r", "c", and so on).
  */
 SR_API char **sr_parse_triggerstring(struct sr_dev *dev,
                                     const char *triggerstring)
@@ -126,14 +144,18 @@ SR_API char **sr_parse_triggerstring(struct sr_dev *dev,
        error = FALSE;
 
        if (!(triggerlist = g_try_malloc0(max_probes * sizeof(char *)))) {
-               sr_err("session file: %s: metafile malloc failed", __func__);
+               sr_err("strutil: %s: triggerlist malloc failed", __func__);
                return NULL;
        }
 
        tokens = g_strsplit(triggerstring, ",", max_probes);
-       trigger_types = dev->plugin->get_dev_info(0, SR_DI_TRIGGER_TYPES);
-       if (trigger_types == NULL)
+
+       trigger_types = dev->driver->dev_info_get(0, SR_DI_TRIGGER_TYPES);
+       if (!trigger_types) {
+               sr_err("strutil: %s: Device doesn't support any triggers.",
+                      __func__);
                return NULL;
+       }
 
        for (i = 0; tokens[i]; i++) {
                if (tokens[i][0] < '0' || tokens[i][0] > '9') {
@@ -153,7 +175,7 @@ SR_API char **sr_parse_triggerstring(struct sr_dev *dev,
                }
 
                if (probenum < 1 || probenum > max_probes) {
-                       sr_err("Invalid probe.\n");
+                       sr_err("strutil: Invalid probe (%d).\n", probenum);
                        error = TRUE;
                        break;
                }
@@ -161,8 +183,8 @@ SR_API char **sr_parse_triggerstring(struct sr_dev *dev,
                if ((trigger = strchr(tokens[i], '='))) {
                        for (tc = ++trigger; *tc; tc++) {
                                if (strchr(trigger_types, *tc) == NULL) {
-                                       sr_err("Unsupported trigger type "
-                                              "'%c'\n", *tc);
+                                       sr_err("strutil: Unsupported trigger "
+                                              "type '%c'.\n", *tc);
                                        error = TRUE;
                                        break;
                                }