From 2e6ab58f37f142117921de04ebb07c71efef0a6e Mon Sep 17 00:00:00 2001
From: Robert James Kaes <rjkaes@users.sourceforge.net>
Date: Sun, 26 May 2002 18:56:06 +0000
Subject: Added the malloc_shared_memory() and calloc_shared_memory() function
 to allow the use of shared memory between all the children.

---
 src/heap.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++-
 src/heap.h |  8 +++++++-
 2 files changed, 56 insertions(+), 2 deletions(-)

(limited to 'src')

diff --git a/src/heap.c b/src/heap.c
index 9a01001..146c87b 100644
--- a/src/heap.c
+++ b/src/heap.c
@@ -1,4 +1,4 @@
-/* $Id: heap.c,v 1.1 2002-05-23 04:41:10 rjkaes Exp $
+/* $Id: heap.c,v 1.2 2002-05-26 18:56:06 rjkaes Exp $
  *
  * Debugging versions of various heap related functions are combined
  * here.  The debugging versions include assertions and also print
@@ -90,3 +90,51 @@ debugging_strdup(const char* s, const char* file, unsigned long line)
 	fprintf(stderr, "{strdup: %p:%u} %s:%lu\n", ptr, len, file, line);
 	return ptr;
 }
+
+/*
+ * Allocate a block of memory in the "shared" memory region
+ */
+void*
+malloc_shared_memory(size_t size)
+{
+	int fd;
+	void* ptr;
+
+	assert(size > 0);
+       
+#ifdef MAP_ANON
+	ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_SHARED, -1, 0);
+#else
+	fd = open("/dev/zero", O_RDWR, 0);
+
+	ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	close(fd);
+#endif
+
+	return ptr;
+}
+
+/*
+ * Allocate a block of memory from the "shared" region an initialize it to
+ * zero.
+ */
+void*
+calloc_shared_memory(size_t nmemb, size_t size)
+{
+	void* ptr;
+	long length;
+
+	assert(nmemb > 0);
+	assert(size > 0);
+
+	length = nmemb * size;
+
+	ptr = malloc_shared_memory(length);
+	if (!ptr)
+		return NULL;
+
+	memset(ptr, 0, length);
+
+	return ptr;
+}
+
diff --git a/src/heap.h b/src/heap.h
index fca28cb..1bfe47a 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -1,4 +1,4 @@
-/* $Id: heap.h,v 1.1 2002-05-23 04:41:10 rjkaes Exp $
+/* $Id: heap.h,v 1.2 2002-05-26 18:56:06 rjkaes Exp $
  *
  * See 'heap.c' for a detailed description.
  *
@@ -46,4 +46,10 @@ extern char *debugging_strdup(const char* s, const char* file,
 #  define safestrdup(x) strdup(x)
 #endif
 
+/*
+ * Allocate memory from the "shared" region of memory.
+ */
+extern void* malloc_shared_memory(size_t size);
+extern void* calloc_shared_memory(size_t nmemb, size_t size);
+
 #endif
-- 
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