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-rwxr-xr-xtap-win32/mem.c190
1 files changed, 190 insertions, 0 deletions
diff --git a/tap-win32/mem.c b/tap-win32/mem.c
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index 0000000..5df7206
--- /dev/null
+++ b/tap-win32/mem.c
@@ -0,0 +1,190 @@
+/*
+ * TAP-Win32 -- A kernel driver to provide virtual tap device functionality
+ * on Windows. Originally derived from the CIPE-Win32
+ * project by Damion K. Wilson, with extensive modifications by
+ * James Yonan.
+ *
+ * All source code which derives from the CIPE-Win32 project is
+ * Copyright (C) Damion K. Wilson, 2003, and is released under the
+ * GPL version 2 (see below).
+ *
+ * All other source code is Copyright (C) 2002-2005 OpenVPN Solutions LLC,
+ * and is released under the GPL version 2 (see below).
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (see the file COPYING included with this
+ * distribution); if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+//------------------
+// Memory Management
+//------------------
+
+PVOID
+MemAlloc (ULONG p_Size, BOOLEAN zero)
+{
+ PVOID l_Return = NULL;
+
+ if (p_Size)
+ {
+ __try
+ {
+ if (NdisAllocateMemoryWithTag (&l_Return, p_Size, 'APAT')
+ == NDIS_STATUS_SUCCESS)
+ {
+ if (zero)
+ NdisZeroMemory (l_Return, p_Size);
+ }
+ else
+ l_Return = NULL;
+ }
+ __except (EXCEPTION_EXECUTE_HANDLER)
+ {
+ l_Return = NULL;
+ }
+ }
+
+ return l_Return;
+}
+
+VOID
+MemFree (PVOID p_Addr, ULONG p_Size)
+{
+ if (p_Addr && p_Size)
+ {
+ __try
+ {
+#if DBG
+ NdisZeroMemory (p_Addr, p_Size);
+#endif
+ NdisFreeMemory (p_Addr, p_Size, 0);
+ }
+ __except (EXCEPTION_EXECUTE_HANDLER)
+ {
+ }
+ }
+}
+
+/*
+ * Circular queue management routines.
+ */
+
+#define QUEUE_BYTE_ALLOCATION(size) \
+ (sizeof (Queue) + (size * sizeof (PVOID)))
+
+#define QUEUE_ADD_INDEX(var, inc) \
+{ \
+ var += inc; \
+ if (var >= q->capacity) \
+ var -= q->capacity; \
+ MYASSERT (var < q->capacity); \
+}
+
+#define QUEUE_SANITY_CHECK() \
+ MYASSERT (q != NULL && q->base < q->capacity && q->size <= q->capacity)
+
+#define QueueCount(q) (q->size)
+
+#define UPDATE_MAX_SIZE() \
+{ \
+ if (q->size > q->max_size) \
+ q->max_size = q->size; \
+}
+
+Queue *
+QueueInit (ULONG capacity)
+{
+ Queue *q;
+
+ MYASSERT (capacity > 0);
+ q = (Queue *) MemAlloc (QUEUE_BYTE_ALLOCATION (capacity), TRUE);
+ if (!q)
+ return NULL;
+
+ q->base = q->size = 0;
+ q->capacity = capacity;
+ q->max_size = 0;
+ return q;
+}
+
+VOID
+QueueFree (Queue *q)
+{
+ if (q)
+ {
+ QUEUE_SANITY_CHECK ();
+ MemFree (q, QUEUE_BYTE_ALLOCATION (q->capacity));
+ }
+}
+
+PVOID
+QueuePush (Queue *q, PVOID item)
+{
+ ULONG dest;
+ QUEUE_SANITY_CHECK ();
+ if (q->size == q->capacity)
+ return NULL;
+ dest = q->base;
+ QUEUE_ADD_INDEX (dest, q->size);
+ q->data[dest] = item;
+ ++q->size;
+ UPDATE_MAX_SIZE();
+ return item;
+}
+
+PVOID
+QueuePop (Queue *q)
+{
+ ULONG oldbase;
+ QUEUE_SANITY_CHECK ();
+ if (!q->size)
+ return NULL;
+ oldbase = q->base;
+ QUEUE_ADD_INDEX (q->base, 1);
+ --q->size;
+ UPDATE_MAX_SIZE();
+ return q->data[oldbase];
+}
+
+PVOID
+QueueExtract (Queue *q, PVOID item)
+{
+ ULONG src, dest, count, n;
+ QUEUE_SANITY_CHECK ();
+ n = 0;
+ src = dest = q->base;
+ count = q->size;
+ while (count--)
+ {
+ if (item == q->data[src])
+ {
+ ++n;
+ --q->size;
+ }
+ else
+ {
+ q->data[dest] = q->data[src];
+ QUEUE_ADD_INDEX (dest, 1);
+ }
+ QUEUE_ADD_INDEX (src, 1);
+ }
+ if (n)
+ return item;
+ else
+ return NULL;
+}
+
+#undef QUEUE_BYTE_ALLOCATION
+#undef QUEUE_ADD_INDEX
+#undef QUEUE_SANITY_CHECK
+#undef UPDATE_MAX_SIZE