From: Uwe Hermann <redacted>
Date: Mon, 30 Dec 2019 15:31:25 +0000 (+0100)
Subject: srd_decoder_load(): Error out upon various duplicate IDs.
X-Git-Url: https://sigrok.org/gitweb/?p=libsigrokdecode.git;a=commitdiff_plain;h=1734f4c263201ae4b3aeab6b9ffc7f0eb23fdffd

srd_decoder_load(): Error out upon various duplicate IDs.
---

diff --git a/HACKING b/HACKING
index c5f24f5..9f2f143 100644
--- a/HACKING
+++ b/HACKING
@@ -150,6 +150,19 @@ Protocol decoder guidelines
    protocol decoder, e.g., UART) via "sigrok-cli -P uart --show", or in various
    other places in GUIs.
 
+ - Input IDs, output IDs, tags, channel IDs, option IDs, annotation class IDs,
+   annotation row IDs, and binary class IDs each must be unique.
+
+ - Annotation class IDs must not overlap with annotation row IDs.
+   For example, you cannot have an annotation row named "foo" if you already
+   have an annotation class named "foo". This avoids confusion for users
+   and simplifies e.g. command-line usage of decoders.
+
+ - Annotation class IDs should generally be singular, annotation row IDs
+   should generally be plural. Example: UART annotation classes could be
+   named "stop-bit" or "parity-bit" (singular), the annotation row containing
+   these annotation classes could be named "bits" (plural).
+
  - Generally use strings for states (of the PD state machine), not integers.
    This avoids having to keep a list of state definitions at the top of file.
    The performance overhead for this is negligible in practice.
diff --git a/decoder.c b/decoder.c
index cef4f29..fc6ae07 100644
--- a/decoder.c
+++ b/decoder.c
@@ -668,6 +668,53 @@ SRD_PRIV long srd_decoder_apiver(const struct srd_decoder *d)
 	return apiver;
 }
 
+static gboolean contains_duplicates(GSList *list)
+{
+	for (GSList *l1 = list; l1; l1 = l1->next) {
+		for (GSList *l2 = l1->next; l2; l2 = l2->next)
+			if (!strcmp(l1->data, l2->data))
+				return TRUE;
+	}
+
+	return FALSE;
+}
+
+static gboolean contains_duplicate_ids(GSList *list1, GSList *list2)
+{
+	for (GSList *l1 = list1; l1; l1 = l1->next) {
+		unsigned int cnt = 0;
+		const char **s1 = l1->data;
+		for (GSList *l2 = list2; l2; l2 = l2->next) {
+			const char **s2 = l2->data;
+			if (!strcmp(s1[0], s2[0]))
+				cnt++;
+			if ((list1 == list2) && cnt > 1)
+				return TRUE;
+			if ((list1 != list2) && cnt > 0)
+				return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
+static gboolean contains_duplicate_row_ids(GSList *list1, GSList *list2)
+{
+	for (GSList *l1 = list1; l1; l1 = l1->next) {
+		unsigned int cnt = 0;
+		const struct srd_decoder_annotation_row *r1 = l1->data;
+		for (GSList *l2 = list2; l2; l2 = l2->next) {
+			const struct srd_decoder_annotation_row *r2 = l2->data;
+			if (!strcmp(r1->id, r2->id))
+				cnt++;
+			if (cnt > 1)
+				return TRUE;
+		}
+	}
+
+	return FALSE;
+}
+
 /**
  * Load a protocol decoder module into the embedded Python interpreter.
  *
@@ -842,6 +889,61 @@ SRD_API int srd_decoder_load(const char *module_name)
 		goto err_out;
 	}
 
+	if (contains_duplicates(d->inputs)) {
+		fail_txt = "duplicate input IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicates(d->outputs)) {
+		fail_txt = "duplicate output IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicates(d->tags)) {
+		fail_txt = "duplicate tags";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->channels, d->channels)) {
+		fail_txt = "duplicate channel IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->opt_channels, d->opt_channels)) {
+		fail_txt = "duplicate optional channel IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->channels, d->opt_channels)) {
+		fail_txt = "channel and optional channel IDs contain duplicates";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->options, d->options)) {
+		fail_txt = "duplicate option IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->annotations, d->annotations)) {
+		fail_txt = "duplicate annotation class IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicate_row_ids(d->annotation_rows, d->annotation_rows)) {
+		fail_txt = "duplicate annotation row IDs";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->annotations, d->annotation_rows)) {
+		fail_txt = "annotation class/row IDs contain duplicates";
+		goto err_out;
+	}
+
+	if (contains_duplicate_ids(d->binary, d->binary)) {
+		fail_txt = "duplicate binary class IDs";
+		goto err_out;
+	}
+
 	PyGILState_Release(gstate);
 
 	/* Append it to the list of loaded decoders. */