1 files changed, 104 insertions, 0 deletions
diff --git a/src/backend/storage/shmem.h b/src/backend/storage/shmem.h
new file mode 100644
index 00000000000..a00b33581a4
--- /dev/null
+++ b/src/backend/storage/shmem.h
@@ -0,0 +1,104 @@
+/*-------------------------------------------------------------------------
+ *
+ * shmem.h--
+ *    shared memory management structures
+ *
+ *
+ * Copyright (c) 1994, Regents of the University of California
+ *
+ * $Id: shmem.h,v 1.1.1.1 1996/07/09 06:21:53 scrappy Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef	SHMEM_H
+#define SHMEM_H
+
+#include "storage/spin.h"		/* for SPINLOCK */
+#include "utils/hsearch.h"		/* for HTAB */
+
+/* The shared memory region can start at a different address
+ * in every process.  Shared memory "pointers" are actually
+ * offsets relative to the start of the shared memory region(s).
+ */
+typedef unsigned long SHMEM_OFFSET;
+#define INVALID_OFFSET (-1)
+#define BAD_LOCATION (-1)
+
+/* start of the lowest shared memory region.  For now, assume that
+ * there is only one shared memory region 
+ */
+extern SHMEM_OFFSET ShmemBase;
+
+
+/* coerce an offset into a pointer in this process's address space */
+#define MAKE_PTR(xx_offs)\
+  (ShmemBase+((unsigned long)(xx_offs)))
+
+/* coerce a pointer into a shmem offset */
+#define MAKE_OFFSET(xx_ptr)\
+  (SHMEM_OFFSET) (((unsigned long)(xx_ptr))-ShmemBase)
+
+#define SHM_PTR_VALID(xx_ptr)\
+  (((unsigned long)xx_ptr) > ShmemBase)
+
+/* cannot have an offset to ShmemFreeStart (offset 0) */
+#define SHM_OFFSET_VALID(xx_offs)\
+  ((xx_offs != 0) && (xx_offs != INVALID_OFFSET))
+
+
+extern SPINLOCK ShmemLock;
+extern SPINLOCK BindingLock;
+
+/* shmemqueue.c */
+typedef struct SHM_QUEUE {
+    SHMEM_OFFSET	prev;
+    SHMEM_OFFSET	next;
+} SHM_QUEUE;
+
+/* shmem.c */
+extern void ShmemBindingTabReset();
+extern void ShmemCreate(unsigned int key, unsigned int size);
+extern int InitShmem(unsigned int key, unsigned int size);
+extern long *ShmemAlloc(unsigned long size);
+extern int ShmemIsValid(unsigned long addr);
+extern HTAB *ShmemInitHash(char *name, long init_size, long max_size,
+			   HASHCTL *infoP, int hash_flags);
+extern bool ShmemPIDLookup(int pid, SHMEM_OFFSET* locationPtr);
+extern SHMEM_OFFSET ShmemPIDDestroy(int pid);
+extern long *ShmemInitStruct(char *name, unsigned long size,
+			     bool *foundPtr);
+
+
+typedef int TableID;
+
+/* size constants for the binding table */
+        /* max size of data structure string name */
+#define BTABLE_KEYSIZE  (50)
+        /* data in binding table hash bucket */
+#define BTABLE_DATASIZE (sizeof(BindingEnt) - BTABLE_KEYSIZE)
+        /* maximum size of the binding table */
+#define BTABLE_SIZE      (100)
+
+/* this is a hash bucket in the binding table */
+typedef struct {
+    char  	   key[BTABLE_KEYSIZE];	/* string name */
+    unsigned long  location;		/* location in shared mem */
+    unsigned long  size;		/* numbytes allocated for the
+					 * structure
+					 */
+} BindingEnt;
+
+/*
+ * prototypes for functions in shmqueue.c
+ */
+extern void SHMQueueInit(SHM_QUEUE *queue);
+extern bool SHMQueueIsDetached(SHM_QUEUE *queue);
+extern void SHMQueueElemInit(SHM_QUEUE *queue);
+extern void SHMQueueDelete(SHM_QUEUE *queue);
+extern void SHMQueueInsertHD(SHM_QUEUE *queue, SHM_QUEUE *elem);
+extern void SHMQueueInsertTL(SHM_QUEUE *queue, SHM_QUEUE *elem);
+extern void SHMQueueFirst(SHM_QUEUE *queue, Pointer *nextPtrPtr,
+			  SHM_QUEUE *nextQueue);
+extern bool SHMQueueEmpty(SHM_QUEUE *queue);
+
+#endif	/* SHMEM_H */