From: Ondřej Surý <ondrej@isc.org>
Date: Wed, 5 Oct 2022 09:19:52 +0000 (+0200)
Subject: Add extra set of ISC_REFCOUNT_TRACE_{IMPL,DECL} macros
X-Git-Tag: v9.19.8~35^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=118ae66976e72b5b8c12a7ed20091813cc24b246;p=thirdparty%2Fbind9.git

Add extra set of ISC_REFCOUNT_TRACE_{IMPL,DECL} macros

The new ISC_REFCOUNT_TRACE_{IMPL,DECL} macros can be used to add a
reference tracing capability to any unit using the reference counting.
It requires a little bit of extra work in each header as you can't have
a define from inside a define (see rpz.h), but it's fairly easy to add
tracing to any struct using reference counting with these macros.
---

diff --git a/lib/isc/include/isc/refcount.h b/lib/isc/include/isc/refcount.h
index e33cd7df25b..80ba888d06d 100644
--- a/lib/isc/include/isc/refcount.h
+++ b/lib/isc/include/isc/refcount.h
@@ -149,6 +149,53 @@ isc_refcount_decrement(isc_refcount_t *target) {
 		ISC_INSIST(_refs > 0);                                \
 	} while (0)
 
+#define ISC_REFCOUNT_TRACE_DECL(name)                                         \
+	void name##__ref(name##_t *ptr, const char *func, const char *file,   \
+			 unsigned int line);                                  \
+	void name##__unref(name##_t *ptr, const char *func, const char *file, \
+			   unsigned int line);                                \
+	void name##__attach(name##_t *ptr, name##_t **ptrp, const char *func, \
+			    const char *file, unsigned int line);             \
+	void name##__detach(name##_t **ptrp, const char *func,                \
+			    const char *file, unsigned int line)
+
+#define ISC_REFCOUNT_TRACE_IMPL(name, destroy)                                \
+	void name##__ref(name##_t *ptr, const char *func, const char *file,   \
+			 unsigned int line) {                                 \
+		uint_fast32_t refs;                                           \
+		REQUIRE(ptr != NULL);                                         \
+		refs = isc_refcount_increment(&ptr->references);              \
+		fprintf(stderr,                                               \
+			"%s:%s:%s:%u:%p->references = %" PRIuFAST32 "\n",     \
+			__func__, func, file, line, ptr, refs + 1);           \
+	}                                                                     \
+                                                                              \
+	void name##__unref(name##_t *ptr, const char *func, const char *file, \
+			   unsigned int line) {                               \
+		uint_fast32_t refs;                                           \
+		REQUIRE(ptr != NULL);                                         \
+		if ((refs = isc_refcount_decrement(&ptr->references)) == 1) { \
+			destroy(ptr);                                         \
+		}                                                             \
+		fprintf(stderr,                                               \
+			"%s:%s:%s:%u:%p->references = %" PRIuFAST32 "\n",     \
+			__func__, func, file, line, ptr, refs - 1);           \
+	}                                                                     \
+	void name##__attach(name##_t *ptr, name##_t **ptrp, const char *func, \
+			    const char *file, unsigned int line) {            \
+		REQUIRE(ptrp != NULL && *ptrp == NULL);                       \
+		name##__ref(ptr, func, file, line);                           \
+		*ptrp = ptr;                                                  \
+	}                                                                     \
+                                                                              \
+	void name##__detach(name##_t **ptrp, const char *func,                \
+			    const char *file, unsigned int line) {            \
+		REQUIRE(ptrp != NULL && *ptrp != NULL);                       \
+		name##_t *ptr = *ptrp;                                        \
+		*ptrp = NULL;                                                 \
+		name##__unref(ptr, func, file, line);                         \
+	}
+
 #define ISC_REFCOUNT_DECL(name)                             \
 	void name##_ref(name##_t *ptr);                     \
 	void name##_unref(name##_t *ptr);                   \