[DTrace-devel] [PATCH v2 2/3] usdt parser: handle encoded hyphens

[Kris Van Hees]

Signed-off-by: Kris Van Hees <kris.van.hees at oracle.com>
---
 libcommon/usdt_parser_notes.c             | 17 ++++++
 test/unittest/usdt/tst.encoded_hyphens.r  |  0
 test/unittest/usdt/tst.encoded_hyphens.sh | 74 +++++++++++++++++++++++
 3 files changed, 91 insertions(+)
 create mode 100644 test/unittest/usdt/tst.encoded_hyphens.r
 create mode 100755 test/unittest/usdt/tst.encoded_hyphens.sh

diff --git a/libcommon/usdt_parser_notes.c b/libcommon/usdt_parser_notes.c
index fb57f119..d3d744fb 100644
--- a/libcommon/usdt_parser_notes.c
+++ b/libcommon/usdt_parser_notes.c
@@ -471,6 +471,23 @@ parse_usdt_note(int out, dof_helper_t *dhp, usdt_data_t *data,
 	}
 	prbt.off = off;
 
+	/*
+	 * If the probe name has encoded hyphens, perform in-place changing
+	 * from "__" into "-".
+	 */
+	if (strstr(prbt.prb, "__") != NULL) {
+		char		*q;
+		const char	*s = prbt.prb, *e = p;
+
+		for (q = (char *)s; s < e; s++, q++) {
+			if (s[0] == '_' && s[1] == '_') {
+				*q = '-';
+				s++;
+			} else if (s > q)
+				*q = *s;
+		}
+	}
+
 	if ((prp = dt_htab_lookup(prbmap, &prbt)) == NULL) {
 		if ((prp = malloc(sizeof(dt_probe_t))) == NULL) {
 			usdt_error(out, ENOMEM, "Failed to allocate probe");
diff --git a/test/unittest/usdt/tst.encoded_hyphens.r b/test/unittest/usdt/tst.encoded_hyphens.r
new file mode 100644
index 00000000..e69de29b
diff --git a/test/unittest/usdt/tst.encoded_hyphens.sh b/test/unittest/usdt/tst.encoded_hyphens.sh
new file mode 100755
index 00000000..90608e25
--- /dev/null
+++ b/test/unittest/usdt/tst.encoded_hyphens.sh
@@ -0,0 +1,74 @@
+#!/bin/bash
+#
+# Oracle Linux DTrace.
+# Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+# Licensed under the Universal Permissive License v 1.0 as shown at
+# http://oss.oracle.com/licenses/upl.
+#
+if [ $# != 1 ]; then
+	echo expected one argument: '<'dtrace-path'>'
+	exit 2
+fi
+
+dtrace=$1
+CFLAGS="$test_cppflags"
+LDFLAGS="$test_ldflags"
+
+DIRNAME="$tmpdir/usdt-entryreturn.$$.$RANDOM"
+mkdir -p $DIRNAME
+cd $DIRNAME
+
+cat > test.c <<EOF
+#include <sys/sdt.h>
+
+int
+main(int argc, char **argv)
+{
+	DTRACE_PROBE(test_prov, entry);
+	DTRACE_PROBE(test_prov, __entry);
+	DTRACE_PROBE(test_prov, foo__entry);
+	DTRACE_PROBE(test_prov, carpentry);
+	DTRACE_PROBE(test_prov, miniatureturn);
+	DTRACE_PROBE(test_prov, foo__return);
+	DTRACE_PROBE(test_prov, __return);
+	/*
+	 * Unfortunately, a "return" probe is not currently possible due to
+	 * the conflict with a reserved word.
+	 */
+	DTRACE_PROBE(test_prov, done);
+}
+EOF
+
+cat > prov.d <<EOF
+provider test_prov {
+	probe entry();
+	probe __entry();
+	probe foo__entry();
+	probe carpentry();
+	probe miniatureturn();
+	probe foo__return();
+	probe __return();
+	probe done();
+};
+EOF
+
+${CC} ${CFLAGS} -c test.c
+if [ $? -ne 0 ]; then
+	echo "failed to compile test.c" >& 2
+	exit 1
+fi
+$dtrace $dt_flags -G -s prov.d test.o
+if [ $? -ne 0 ]; then
+	echo "failed to create USDT data" >& 2
+	exit 1
+fi
+${CC} ${LDFLAGS} -o test test.o prov.o
+if [ $? -ne 0 ]; then
+	echo "failed to link final executable" >& 2
+	exit 1
+fi
+
+./test
+status=$?
+
+exit $status
-- 
2.43.5