From d8343bd004e95fa2b0f91fc3bb757c701efaedd8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ond=C5=99ej=20Sur=C3=BD?= <ondrej@isc.org>
Date: Tue, 14 Jul 2020 11:33:27 +0200
Subject: [PATCH] Add isc_mem_callocate() and isc_mem_cget() functions

These two functions mimick the standard library calloc(num, size) function
by allocating num*size continuous memory and clearing the memory after
the allocation.
---
 lib/isc/include/isc/mem.h |  7 ++++++-
 lib/isc/mem.c             | 27 +++++++++++++++++++++------
 2 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/lib/isc/include/isc/mem.h b/lib/isc/include/isc/mem.h
index 77119fc92a..0a63939b5b 100644
--- a/lib/isc/include/isc/mem.h
+++ b/lib/isc/include/isc/mem.h
@@ -207,8 +207,11 @@ struct isc_mempool {
 #define ISCMEMFUNC(sfx)	    isc__mem_##sfx
 #define ISCMEMPOOLFUNC(sfx) isc__mempool_##sfx
 
-#define isc_mem_get(c, s)      ISCMEMFUNC(get)((c), (s)_ISC_MEM_FILELINE)
+#define isc_mem_get(c, s) ISCMEMFUNC(get)((c), (s)_ISC_MEM_FILELINE)
+#define isc_mem_cget(c, n, s)  ISCMEMFUNC(cget((c), (n), (s)_ISC_MEM_FILELINE)
 #define isc_mem_allocate(c, s) ISCMEMFUNC(allocate)((c), (s)_ISC_MEM_FILELINE)
+#define isc_mem_callocate(c, n, s) \
+	ISCMEMFUNC(callocate)((c), (n), (s)_ISC_MEM_FILELINE)
 #define isc_mem_reallocate(c, p, s) \
 	ISCMEMFUNC(reallocate)((c), (p), (s)_ISC_MEM_FILELINE)
 #define isc_mem_strdup(c, p) ISCMEMFUNC(strdup)((c), (p)_ISC_MEM_FILELINE)
@@ -578,9 +581,11 @@ isc_mempool_setfillcount(isc_mempool_t *mpctx, unsigned int limit);
  * Pseudo-private functions for use via macros.  Do not call directly.
  */
 void *ISCMEMFUNC(get)(isc_mem_t *, size_t _ISC_MEM_FLARG);
+void *ISCMEMFUNC(cget)(isc_mem_t *, size_t, size_t _ISC_MEM_FLARG);
 void  ISCMEMFUNC(putanddetach)(isc_mem_t **, void *, size_t _ISC_MEM_FLARG);
 void  ISCMEMFUNC(put)(isc_mem_t *, void *, size_t _ISC_MEM_FLARG);
 void *ISCMEMFUNC(allocate)(isc_mem_t *, size_t _ISC_MEM_FLARG);
+void *ISCMEMFUNC(callocate)(isc_mem_t *, size_t, size_t _ISC_MEM_FLARG);
 void *ISCMEMFUNC(reallocate)(isc_mem_t *, void *, size_t _ISC_MEM_FLARG);
 void  ISCMEMFUNC(free)(isc_mem_t *, void *_ISC_MEM_FLARG);
 char *ISCMEMFUNC(strdup)(isc_mem_t *, const char *_ISC_MEM_FLARG);
diff --git a/lib/isc/mem.c b/lib/isc/mem.c
index 91719df740..cc639b5018 100644
--- a/lib/isc/mem.c
+++ b/lib/isc/mem.c
@@ -1298,6 +1298,26 @@ isc__mem_allocate(isc_mem_t *ctx0, size_t size FLARG) {
 	return (si);
 }
 
+void *
+isc__mem_callocate(isc_mem_t *ctx0, size_t num, size_t size FLARG) {
+	size_t numsize;
+
+	ISC_MUL_OVERFLOW(num, size, &numsize);
+	void *ptr = isc__mem_allocate(ctx0, numsize FLARG_PASS);
+	memset(ptr, 0, numsize);
+	return (ptr);
+}
+
+void *
+isc__mem_cget(isc_mem_t *ctx0, size_t num, size_t size FLARG) {
+	size_t numsize;
+
+	ISC_MUL_OVERFLOW(num, size, &numsize);
+	void *ptr = isc__mem_get(ctx0, numsize FLARG_PASS);
+	memset(ptr, 0, numsize);
+	return (ptr);
+}
+
 void *
 isc__mem_reallocate(isc_mem_t *ctx0, void *ptr, size_t size FLARG) {
 	REQUIRE(VALID_CONTEXT(ctx0));
@@ -2534,12 +2554,7 @@ isc__malloc(size_t size FLARG) {
 
 void *
 isc__calloc(size_t num, size_t size FLARG) {
-	size_t numsize;
-
-	ISC_MUL_OVERFLOW(num, size, &numsize);
-	void *ptr = isc__mem_allocate(isc__mem_mctx, numsize FLARG_PASS);
-	memset(ptr, 0, numsize);
-	return (ptr);
+	return (isc__mem_callocate(isc__mem_mctx, num, size FLARG_PASS));
 }
 
 void *