From 1162a4e02a6594dbb4f57fd288a5d20ab467e4d7 Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Tue, 5 Sep 2000 03:30:19 +0000
Subject: [PATCH] New function isc_mem_putanddetach().

---
 lib/isc/include/isc/mem.h | 11 ++++++++++-
 lib/isc/mem.c             | 41 ++++++++++++++++++++++++++++++++++++++-
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/lib/isc/include/isc/mem.h b/lib/isc/include/isc/mem.h
index dc595d9ddb..11cd3c28bc 100644
--- a/lib/isc/include/isc/mem.h
+++ b/lib/isc/include/isc/mem.h
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: mem.h,v 1.42 2000/08/31 16:58:28 gson Exp $ */
+/* $Id: mem.h,v 1.43 2000/09/05 03:30:19 marka Exp $ */
 
 #ifndef ISC_MEM_H
 #define ISC_MEM_H 1
@@ -102,6 +102,11 @@ extern unsigned int isc_mem_debugging;
 		isc__mem_put((c), (p), (s) _ISC_MEM_FILELINE); \
 		(p) = NULL; \
 	} while (0)
+#define isc_mem_putanddetach(c, p, s) \
+	do { \
+		isc__mem_putanddetach((c), (p), (s) _ISC_MEM_FILELINE); \
+		(p) = NULL; \
+	} while (0)
 #define isc_mem_free(c, p) \
 	do { \
 		isc__mem_free((c), (p) _ISC_MEM_FILELINE); \
@@ -114,6 +119,8 @@ extern unsigned int isc_mem_debugging;
 	} while (0)
 #else
 #define isc_mem_put(c, p, s)	isc__mem_put((c), (p), (s) _ISC_MEM_FILELINE)
+#define isc_mem_putanddetach(c, p, s) \
+	isc__mem_putanddetach((c), (p), (s) _ISC_MEM_FILELINE)
 #define isc_mem_free(c, p)	isc__mem_free((c), (p) _ISC_MEM_FILELINE)
 #define isc_mempool_put(c, p)	isc__mempool_put((c), (p) _ISC_MEM_FILELINE)
 #endif
@@ -127,6 +134,8 @@ isc_result_t			isc_mem_ondestroy(isc_mem_t *ctx,
 						  isc_event_t **event);
 void *				isc__mem_get(isc_mem_t *, size_t
 					     _ISC_MEM_FLARG);
+void 				isc__mem_putanddetach(isc_mem_t **, void *,
+						      size_t _ISC_MEM_FLARG);
 void 				isc__mem_put(isc_mem_t *, void *,
 					     size_t _ISC_MEM_FLARG);
 isc_result_t			isc_mem_preallocate(isc_mem_t *);
diff --git a/lib/isc/mem.c b/lib/isc/mem.c
index 977732d81c..e2f36ef4af 100644
--- a/lib/isc/mem.c
+++ b/lib/isc/mem.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: mem.c,v 1.61 2000/08/31 12:15:16 marka Exp $ */
+/* $Id: mem.c,v 1.62 2000/09/05 03:30:18 marka Exp $ */
 
 #include <config.h>
 
@@ -755,6 +755,45 @@ isc_mem_detach(isc_mem_t **ctxp) {
 	*ctxp = NULL;
 }
 
+/*
+ * isc_mem_putanddetach() is the equivalent of:
+ *
+ * mctx = NULL;
+ * isc_mem_attach(ptr->mctx, &mctx);
+ * isc_mem_detach(&ptr->mctx);
+ * isc_mem_put(mctx, ptr, sizeof(*ptr);
+ * isc_mem_detach(&mctx);
+ */
+
+void
+isc__mem_putanddetach(isc_mem_t **ctxp, void *ptr, size_t size FLARG) {
+	isc_mem_t *ctx;
+	isc_boolean_t want_destroy = ISC_FALSE;
+
+	REQUIRE(ctxp != NULL);
+	ctx = *ctxp;
+	REQUIRE(VALID_CONTEXT(ctx));
+	REQUIRE(ptr != NULL);
+
+	/*
+	 * Must be before mem_putunlocked() as ctxp is usually within
+	 * [ptr..ptr+size).
+	 */
+	*ctxp = NULL;
+
+	LOCK(&ctx->lock);
+	DELETE_TRACE(ctx, ptr, size, file, line);
+	mem_putunlocked(ctx, ptr, size);
+	INSIST(ctx->references > 0);
+	ctx->references--;
+	if (ctx->references == 0)
+		want_destroy = ISC_TRUE;
+	UNLOCK(&ctx->lock);
+
+	if (want_destroy)
+		destroy(ctx);
+}
+
 void
 isc_mem_destroy(isc_mem_t **ctxp) {
 	isc_mem_t *ctx;