777 lines
25 KiB
C++
777 lines
25 KiB
C++
//+-------------------------------------------------------------------------
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//
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// Microsoft Windows
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// Copyright (C) Microsoft Corporation, 1992 - 1992.
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//
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// File: lock.cxx
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//
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// Contents: Remote exclusion stuff for docfile
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//
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// Functions: GetAccess
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// ReleaseAccess
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// GetOpen
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// ReleaseOpen
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//
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// History: 09-Mar-92 PhilipLa Created.
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// 20-Jul-93 DrewB Added dual locking for Mac
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// compatibility
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//
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//--------------------------------------------------------------------------
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#include <exphead.cxx>
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#pragma hdrstop
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#include <header.hxx>
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#include <lock.hxx>
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// Offset to next lock group from a particular group
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#define OLOCKGROUP 1
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// The docfile originally locked at 0xffffff00
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// It turned out that the Mac can only lock to 0x7fffffff,
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// so for compatibility reasons it was decided that the
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// docfile would lock at both places. Thus, we have one routine
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// that locks with a mask for the offset so that we can
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// selectively suppress the high bit
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// Since lock indices fit easily within 16 bits, the two
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// lock indices are now combined into the existing ULONG
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// value to preserve compatibility with other code. This
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// implies that lock indices from these routines must be
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// handled opaquely since they are no longer simple numbers
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// 09/23/1993 - Further change:
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// To avoid a Netware 2.2 problem we are offsetting the lock regions
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// so that they differ by more than just the high bit. The high
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// lock region was moved to 0xffffff80, moving the low region to
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// 0x7fffff80. The 0x80 was then taken out of the high mask so that
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// the net is no change for high locks and the low locks moved up by 0x80
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// Masks for separate lock locations
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#define MASK_LOW 0x7fffffff
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#ifndef _MAC
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#define MASK_HIGH 0xffffff7f
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#endif
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//In a specific open case (Read-only, deny-write), we don't need to
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//take locks.
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#define P_NOLOCK(df) (!P_WRITE(df) && P_READ(df) && \
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P_DENYWRITE(df) && !P_DENYREAD(df))
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//+--------------------------------------------------------------
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//
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// Function: GetAccessWithMask, private
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//
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// Synopsis: Takes appropriate access locks on an LStream,
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// masking the offset with the given mask
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//
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// Arguments: [plst] - LStream
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// [df] - Permissions needed
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// [ulMask] - Mask
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// [poReturn] - Index of lock taken
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//
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// Returns: Appropriate status code
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//
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// Modifies: [poReturn]
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//
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// History: 08-Apr-92 DrewB Created
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//
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//---------------------------------------------------------------
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#ifdef CODESEGMENTS
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#pragma code_seg(SEG_GetAccessWithMask)
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#endif
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static SCODE GetAccessWithMask(ILockBytes *plst,
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DFLAGS df,
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ULONG ulMask,
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ULONG *poReturn)
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{
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SCODE sc;
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ULARGE_INTEGER ulOffset, cbLength;
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olDebugOut((DEB_ITRACE, "In GetAccessWithMask(%p, %X, %lX, %p)\n",
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plst, df, ulMask, poReturn));
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olAssert((df & ~(DF_READ | DF_WRITE)) == 0 && P_READ(df) != P_WRITE(df));
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*poReturn = NOLOCK;
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ULISet32(ulOffset, OACCESS & ulMask);
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if (P_READ(df))
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{
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ULISet32(cbLength, 1);
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olHChk(plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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for (USHORT i = 0; i < CREADLOCKS; i++)
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{
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ULISetLow(ulOffset, (OREADLOCK+i) & ulMask);
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sc = DfGetScode(plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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if (SUCCEEDED(sc))
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{
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*poReturn = i+1;
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break;
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}
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}
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ULISetLow(ulOffset, OACCESS & ulMask);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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if (i == CREADLOCKS)
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olErr(EH_Err, STG_E_TOOMANYOPENFILES);
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}
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else
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{
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olAssert((OACCESS + 1 == OREADLOCK) && aMsg("Bad lock dependency"));
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ULISet32(cbLength, 1 + CREADLOCKS);
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olChk(DfGetScode(plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE)));
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*poReturn = 0xFFFF;
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}
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olDebugOut((DEB_ITRACE, "Out GetAccessWithMask => %lu\n", *poReturn));
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olAssert(*poReturn != NOLOCK);
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return S_OK;
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EH_Err:
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return sc;
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}
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//+--------------------------------------------------------------
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//
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// Function: ReleaseAccessWithMask, private
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//
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// Synopsis: Releases an access lock at the given offset
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//
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// Arguments: [plst] - LStream that is locked
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// [df] - Permission to release
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// [offset] - Offset of locks taken
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// [ulMask] - Mask
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//
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// History: 08-Apr-92 DrewB Created
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//
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//---------------------------------------------------------------
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#ifdef CODESEGMENTS
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#pragma code_seg(SEG_ReleaseAccessWithMask)
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#endif
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static void ReleaseAccessWithMask(ILockBytes *plst,
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DFLAGS df,
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ULONG offset,
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ULONG ulMask)
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{
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ULARGE_INTEGER ulOffset, cbLength;
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olDebugOut((DEB_ITRACE, "In ReleaseAccessWithMask(%p, %lX, %lu, %lX)\n",
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plst, df, offset, ulMask));
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olAssert((df & ~(DF_READ | DF_WRITE)) == 0 && P_READ(df) != P_WRITE(df));
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if (offset == NOLOCK)
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return;
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if (P_READ(df))
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{
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ULISet32(ulOffset, (offset+OREADLOCK-1) & ulMask);
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ULISet32(cbLength, 1);
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olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE))) &&
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aMsg("Non-fatal (Removable media?)"));
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}
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else
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{
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olAssert((OACCESS + 1 == OREADLOCK) && aMsg("Bad lock dependency"));
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ULISet32(ulOffset, OACCESS & ulMask);
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ULISet32(cbLength, 1 + CREADLOCKS);
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olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE))) &&
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aMsg("Non-fatal (Removable media?)"));
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}
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olDebugOut((DEB_ITRACE, "Out ReleaseAccessWithMask\n"));
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}
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//+--------------------------------------------------------------
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//
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// Function: GetAccess, public
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//
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// Synopsis: Takes appropriate access locks on an LStream
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//
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// Arguments: [plst] - LStream
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// [df] - Permissions needed
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// [poReturn] - Index of lock taken
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//
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// Returns: Appropriate status code
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//
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// Modifies: [poReturn]
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//
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// History: 08-Apr-92 DrewB Created
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//
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//---------------------------------------------------------------
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#ifdef CODESEGMENTS
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#pragma code_seg(SEG_GetAccess)
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#endif
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SCODE GetAccess(ILockBytes *plst,
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DFLAGS df,
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ULONG *poReturn)
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{
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SCODE sc;
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olDebugOut((DEB_ITRACE, "In GetAccess(%p, %X, %p)\n",
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plst, df, poReturn));
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// Make sure our lock region hasn't overflowed 32 bits
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olAssert(OLOCKREGIONEND > OACCESS);
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// If we aren't locking high, this dual lock business is unnecessary
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olAssert(OACCESS & 0x80000000);
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olChk(GetAccessWithMask(plst, df, MASK_LOW, poReturn));
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olAssert(*poReturn < 0x10000);
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#ifndef _MAC
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#ifdef _LOCK_HIGH
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ULONG ulIndex;
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olChkTo(EH_Low, GetAccessWithMask(plst, df, MASK_HIGH, &ulIndex));
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olAssert(ulIndex < 0x10000);
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*poReturn |= ulIndex << 16;
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#endif
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#endif
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olDebugOut((DEB_ITRACE, "Out GetAccess => %lu\n", *poReturn));
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return S_OK;
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#ifndef _MAC
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#ifdef _LOCK_HIGH
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EH_Low:
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ReleaseAccessWithMask(plst, df, *poReturn, MASK_LOW);
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#endif
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#endif
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EH_Err:
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*poReturn = NOLOCK;
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return sc;
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}
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//+--------------------------------------------------------------
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//
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// Function: ReleaseAccess, public
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//
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// Synopsis: Releases access locks
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//
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// Arguments: [plst] - LStream that is locked
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// [df] - Permission to release
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// [offset] - Offset of locks taken
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//
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// History: 08-Apr-92 DrewB Created
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//
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//---------------------------------------------------------------
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#ifdef CODESEGMENTS
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#pragma code_seg(SEG_ReleaseAccess)
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#endif
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void ReleaseAccess(ILockBytes *plst, DFLAGS df, ULONG offset)
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{
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olDebugOut((DEB_ITRACE, "In ReleaseAccess(%p, %lX, %lu)\n",
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plst, df, offset));
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ReleaseAccessWithMask(plst, df, offset & 0xffff, MASK_LOW);
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#ifndef _MAC
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#ifdef _LOCK_HIGH
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ReleaseAccessWithMask(plst, df, offset >> 16, MASK_HIGH);
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#endif
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#endif
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olDebugOut((DEB_ITRACE, "Out ReleaseAccess\n"));
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}
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//+--------------------------------------------------------------
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//
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// Function: GetOpenWithMask, private
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//
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// Synopsis: Gets locks on an LStream during opening, masking the offset
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//
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// Arguments: [plst] - LStream
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// [df] - Permissions to take
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// [fCheck] - Whether to check for existing locks or not
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// [ulMask] - Mask
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// [puReturn] - Index of lock taken
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//
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// Returns: Appropriate status code
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//
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// Modifies: [puReturn]
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//
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// History: 08-Apr-92 DrewB Created
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//
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//---------------------------------------------------------------
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#ifdef CODESEGMENTS
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#pragma code_seg(SEG_GetOpenWithMask)
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#endif
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static SCODE GetOpenWithMask(ILockBytes *plst,
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DFLAGS df,
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BOOL fCheck,
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ULONG ulMask,
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ULONG *puReturn)
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{
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SCODE sc;
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ULONG i;
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ULARGE_INTEGER ulOffset, cbLength;
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olDebugOut((DEB_ITRACE, "In GetOpenWithMask(%p, %lX, %d, %lX, %p)\n",
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plst, df, fCheck, ulMask, puReturn));
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*puReturn = NOLOCK;
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ULISet32(ulOffset, OUPDATE & ulMask);
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ULISet32(cbLength, 1);
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olHChk(plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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if (fCheck)
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{
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ULISetLow(cbLength, COPENLOCKS);
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if (P_DENYREAD(df))
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{
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ULISetLow(ulOffset, OOPENREADLOCK & ulMask);
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olHChkTo(EH_UnlockUpdate, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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}
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#ifndef USE_NOSNAPSHOT
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if (P_DENYWRITE(df))
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#else
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if (P_DENYWRITE(df) || P_NOSNAPSHOT(df))
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#endif
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{
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ULISetLow(ulOffset, OOPENWRITELOCK & ulMask);
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sc = plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE);
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if (SUCCEEDED(sc))
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{
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olHVerSucc(plst->UnlockRegion(ulOffset,
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cbLength,
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LOCK_ONLYONCE));
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}
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#ifdef USE_NOSNAPSHOT
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else if (P_NOSNAPSHOT(df))
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{
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//There is an existing writer. In order for this
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//open to succeed, there must also be a lock in the
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//no-snapshot region. Otherwise we have a case where
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//a normal open proceeded a no-snapshot open attempt,
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//and mixing modes is not allowed.
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ULISetLow(ulOffset, OOPENNOSNAPSHOTLOCK & ulMask);
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sc = plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE);
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if (SUCCEEDED(sc))
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{
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//There was no no-snapshot lock. No mixing modes,
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//so fail here.
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olHVerSucc(plst->UnlockRegion(ulOffset,
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cbLength,
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LOCK_ONLYONCE));
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olErr(EH_UnlockUpdate, STG_E_LOCKVIOLATION);
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}
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}
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#endif
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else
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{
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olErr(EH_UnlockUpdate, sc);
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}
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}
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if (P_READ(df))
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{
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ULISetLow(ulOffset, OOPENDENYREADLOCK & ulMask);
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olHChkTo(EH_UnlockUpdate, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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}
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if (P_WRITE(df))
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{
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ULISetLow(ulOffset, OOPENDENYWRITELOCK & ulMask);
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#ifndef USE_NOSNAPSHOT
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olHChkTo(EH_UnlockUpdate, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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#else
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sc = plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE);
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if (P_NOSNAPSHOT(df) && (sc == STG_E_LOCKVIOLATION))
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{
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//The deny-write lock may be the fake holder we use for
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//no-snapshot mode. Check then no-snapshot region - if
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//there is a lock there too, then this succeeds, otherwise
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//the deny-write lock is real and we must fail the call.
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ULISetLow(ulOffset, OOPENNOSNAPSHOTLOCK & ulMask);
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sc = plst->LockRegion(ulOffset, cbLength, LOCK_ONLYONCE);
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if (sc != STG_E_LOCKVIOLATION)
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{
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if (SUCCEEDED(sc))
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{
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olHVerSucc(plst->UnlockRegion(ulOffset,
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cbLength,
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LOCK_ONLYONCE));
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olErr(EH_UnlockUpdate, STG_E_LOCKVIOLATION);
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}
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else
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{
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olErr(EH_UnlockUpdate, sc);
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}
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}
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}
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else
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{
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olHChkTo(EH_UnlockUpdate, sc);
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olHVerSucc(plst->UnlockRegion(ulOffset,
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cbLength,
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LOCK_ONLYONCE));
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}
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#endif
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}
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}
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//If we are read-only and deny-write, and we are on our
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// ILockBytes, we don't need to lock and can rely on the FS
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// to handle the access control.
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if (P_NOLOCK(df))
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{
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//QueryInterface to see if this ILockBytes is ours
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IFileLockBytes *pfl;
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if (SUCCEEDED(plst->QueryInterface(IID_IFileLockBytes,
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(void **) &pfl)))
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{
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pfl->Release();
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ULISetLow(ulOffset, OUPDATE & ulMask);
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ULISetLow(cbLength, 1);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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*puReturn = NOLOCK;
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return S_OK;
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}
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}
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ULISetLow(cbLength, 1);
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for (i = 0; i < COPENLOCKS; i = i + OLOCKGROUP)
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{
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ULISetLow(ulOffset, (OOPENREADLOCK+i) & ulMask);
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olHChkTo(EH_Loop, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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ULISetLow(ulOffset, (OOPENWRITELOCK+i) & ulMask);
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olHChkTo(EH_UnlockR, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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ULISetLow(ulOffset, (OOPENDENYREADLOCK+i) & ulMask);
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olHChkTo(EH_UnlockW, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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ULISetLow(ulOffset, (OOPENDENYWRITELOCK+i) & ulMask);
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#ifdef USE_NOSNAPSHOT
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olHChkTo(EH_UnlockDR, plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE));
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if (P_NOSNAPSHOT(df))
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{
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//Note that in the non no-snapshot case we don't need to
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//grab this lock, unlike the others where we must grab all
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//four to make sure we have a valid slot. This is because
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//a no-snapshot open will always have a corresponding
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//deny-write lock in the same slot.
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ULISetLow(ulOffset, (OOPENNOSNAPSHOTLOCK+i) & ulMask);
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if (SUCCEEDED(DfGetScode(plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE))))
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{
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break;
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}
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//Unlock the deny-write lock, then all the rest.
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ULISetLow(ulOffset, (OOPENDENYWRITELOCK + i));
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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}
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else
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{
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//We're not no-snapshot, and we've gotten all our locks
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// successfully, so bail.
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break;
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}
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EH_UnlockDR:
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#else
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if (SUCCEEDED(DfGetScode(plst->LockRegion(ulOffset, cbLength,
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LOCK_ONLYONCE))))
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break;
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#endif //USE_NOSNAPSHOT
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ULISetLow(ulOffset, (OOPENDENYREADLOCK+i) & ulMask);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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EH_UnlockW:
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ULISetLow(ulOffset, (OOPENWRITELOCK+i) & ulMask);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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EH_UnlockR:
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ULISetLow(ulOffset, (OOPENREADLOCK+i) & ulMask);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
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EH_Loop:
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;
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}
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if (i >= COPENLOCKS)
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olErr(EH_UnlockUpdate, STG_E_TOOMANYOPENFILES);
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if (!P_READ(df))
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{
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ULISetLow(ulOffset, (OOPENREADLOCK+i) & ulMask);
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olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
}
|
|
if (!P_WRITE(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENWRITELOCK+i) & ulMask);
|
|
olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
}
|
|
if (!P_DENYREAD(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENDENYREADLOCK+i) & ulMask);
|
|
olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
}
|
|
#ifdef USE_NOSNAPSHOT
|
|
if (!P_DENYWRITE(df) && !P_NOSNAPSHOT(df))
|
|
#else
|
|
if (!P_DENYWRITE(df))
|
|
#endif
|
|
{
|
|
ULISetLow(ulOffset, (OOPENDENYWRITELOCK+i) & ulMask);
|
|
olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
}
|
|
ULISetLow(ulOffset, OUPDATE & ulMask);
|
|
olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
|
|
// 0 <= i < COPENLOCKS, but 0 is the invalid value, so increment
|
|
// on the way out
|
|
*puReturn = i + 1;
|
|
olAssert(*puReturn != NOLOCK);
|
|
|
|
olDebugOut((DEB_ITRACE, "Out GetOpenWithMask => %lu\n", *puReturn));
|
|
return S_OK;
|
|
EH_UnlockUpdate:
|
|
ULISetLow(ulOffset, OUPDATE & ulMask);
|
|
ULISetLow(cbLength, 1);
|
|
olHVerSucc(plst->UnlockRegion(ulOffset, cbLength, LOCK_ONLYONCE));
|
|
EH_Err:
|
|
return sc;
|
|
}
|
|
|
|
//+--------------------------------------------------------------
|
|
//
|
|
// Function: ReleaseOpenWithMask, private
|
|
//
|
|
// Synopsis: Releases opening locks with offset masking
|
|
//
|
|
// Arguments: [plst] - LStream
|
|
// [df] - Locks taken
|
|
// [offset] - Index of locks
|
|
// [ulMask] - Mask
|
|
//
|
|
// Requires: offset != NOLOCK
|
|
//
|
|
// History: 08-Apr-92 DrewB Created
|
|
//
|
|
//---------------------------------------------------------------
|
|
|
|
#ifdef CODESEGMENTS
|
|
#pragma code_seg(SEG_ReleaseOpenWithMask)
|
|
#endif
|
|
|
|
static void ReleaseOpenWithMask(ILockBytes *plst,
|
|
DFLAGS df,
|
|
ULONG offset,
|
|
ULONG ulMask)
|
|
{
|
|
ULARGE_INTEGER ulOffset, cbLength;
|
|
|
|
olDebugOut((DEB_ITRACE, "In ReleaseOpenWithMask(%p, %lX, %lu, %lX)\n",
|
|
plst, df, offset, ulMask));
|
|
|
|
olAssert(offset != NOLOCK);
|
|
|
|
// we incremented at the end of GetOpen, so we decrement here
|
|
// to restore the proper lock index
|
|
offset--;
|
|
|
|
ULISetHigh(ulOffset, 0);
|
|
ULISet32(cbLength, 1);
|
|
if (P_READ(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENREADLOCK+offset) & ulMask);
|
|
olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
|
|
LOCK_ONLYONCE))) &&
|
|
aMsg("Non-fatal (Removable media?)"));
|
|
}
|
|
if (P_WRITE(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENWRITELOCK+offset) & ulMask);
|
|
olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
|
|
LOCK_ONLYONCE))) &&
|
|
aMsg("Non-fatal (Removable media?)"));
|
|
}
|
|
if (P_DENYREAD(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENDENYREADLOCK+offset) & ulMask);
|
|
olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
|
|
LOCK_ONLYONCE))) &&
|
|
aMsg("Non-fatal (Removable media?)"));
|
|
}
|
|
#ifdef USE_NOSNAPSHOT
|
|
if (P_DENYWRITE(df) || P_NOSNAPSHOT(df))
|
|
#else
|
|
if (P_DENYWRITE(df))
|
|
#endif
|
|
{
|
|
ULISetLow(ulOffset, (OOPENDENYWRITELOCK+offset) & ulMask);
|
|
olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
|
|
LOCK_ONLYONCE))) &&
|
|
aMsg("Non-fatal (Removable media?)"));
|
|
}
|
|
#ifdef USE_NOSNAPSHOT
|
|
if (P_NOSNAPSHOT(df))
|
|
{
|
|
ULISetLow(ulOffset, (OOPENNOSNAPSHOTLOCK+offset) & ulMask);
|
|
olVerify(SUCCEEDED(DfGetScode(plst->UnlockRegion(ulOffset, cbLength,
|
|
LOCK_ONLYONCE))) &&
|
|
aMsg("Non-fatal (Removable media?)"));
|
|
}
|
|
#endif
|
|
|
|
olDebugOut((DEB_ITRACE, "Out ReleaseOpenWithMask\n"));
|
|
}
|
|
|
|
//+--------------------------------------------------------------
|
|
//
|
|
// Function: GetOpen, public
|
|
//
|
|
// Synopsis: Gets locks on an LStream during opening
|
|
//
|
|
// Arguments: [plst] - LStream
|
|
// [df] - Permissions to take
|
|
// [fCheck] - Whether to check for existing locks or not
|
|
// [puReturn] - Index of lock taken
|
|
//
|
|
// Returns: Appropriate status code
|
|
//
|
|
// Modifies: [puReturn]
|
|
//
|
|
// History: 08-Apr-92 DrewB Created
|
|
//
|
|
//---------------------------------------------------------------
|
|
|
|
#ifdef CODESEGMENTS
|
|
#pragma code_seg(SEG_GetOpen)
|
|
#endif
|
|
|
|
SCODE GetOpen(ILockBytes *plst,
|
|
DFLAGS df,
|
|
BOOL fCheck,
|
|
ULONG *puReturn)
|
|
{
|
|
SCODE sc;
|
|
|
|
olDebugOut((DEB_ITRACE, "In GetOpen(%p, %lX, %d, %p)\n",
|
|
plst, df, fCheck, puReturn));
|
|
|
|
// Make sure our lock region hasn't overflowed 32 bits
|
|
olAssert(OLOCKREGIONEND > OACCESS);
|
|
|
|
// If we're not locking high, the dual locks are unnecessary
|
|
olAssert(OACCESS & 0x80000000);
|
|
|
|
olChk(GetOpenWithMask(plst, df, fCheck, MASK_LOW, puReturn));
|
|
olAssert(*puReturn < 0x10000);
|
|
#ifndef _MAC
|
|
#ifdef _LOCK_HIGH
|
|
ULONG ulIndex;
|
|
olChkTo(EH_Low, GetOpenWithMask(plst, df, fCheck, MASK_HIGH, &ulIndex));
|
|
olAssert(ulIndex < 0x10000);
|
|
*puReturn |= ulIndex << 16;
|
|
#endif
|
|
#endif
|
|
|
|
olDebugOut((DEB_ITRACE, "Out GetOpen => %lu\n", *puReturn));
|
|
return S_OK;
|
|
|
|
#ifndef _MAC
|
|
#ifdef _LOCK_HIGH
|
|
EH_Low:
|
|
ReleaseOpenWithMask(plst, df, *puReturn, MASK_LOW);
|
|
#endif
|
|
#endif
|
|
EH_Err:
|
|
*puReturn = NOLOCK;
|
|
return sc;
|
|
}
|
|
|
|
//+--------------------------------------------------------------
|
|
//
|
|
// Function: ReleaseOpen, public
|
|
//
|
|
// Synopsis: Releases opening locks
|
|
//
|
|
// Arguments: [plst] - LStream
|
|
// [df] - Locks taken
|
|
// [offset] - Index of locks
|
|
//
|
|
// Requires: offset != NOLOCK
|
|
//
|
|
// History: 08-Apr-92 DrewB Created
|
|
//
|
|
//---------------------------------------------------------------
|
|
|
|
#ifdef CODESEGMENTS
|
|
#pragma code_seg(SEG_ReleaseOpen)
|
|
#endif
|
|
|
|
void ReleaseOpen(ILockBytes *plst, DFLAGS df, ULONG offset)
|
|
{
|
|
olDebugOut((DEB_ITRACE, "In ReleaseOpen(%p, %lX, %lu)\n",
|
|
plst, df, offset));
|
|
|
|
if (offset != NOLOCK)
|
|
{
|
|
ReleaseOpenWithMask(plst, df, offset & 0xffff, MASK_LOW);
|
|
#ifndef _MAC
|
|
#ifdef _LOCK_HIGH
|
|
ReleaseOpenWithMask(plst, df, offset >> 16, MASK_HIGH);
|
|
#endif
|
|
#endif
|
|
}
|
|
olDebugOut((DEB_ITRACE, "Out ReleaseOpen\n"));
|
|
}
|
|
|
|
//+---------------------------------------------------------------------------
|
|
//
|
|
// Function: WaitForAccess, public, 32-bit only
|
|
//
|
|
// Synopsis: Attempts to get access locks, retrying if necessary
|
|
// using exponential backoff
|
|
//
|
|
// Arguments: [plst] - ILockBytes
|
|
// [df] - Access desired
|
|
// [poReturn] - Lock index return
|
|
//
|
|
// Returns: Appropriate status code
|
|
//
|
|
// Modifies: [poReturn]
|
|
//
|
|
// History: 23-Sep-93 DrewB Created
|
|
//
|
|
//----------------------------------------------------------------------------
|
|
|
|
#ifdef WIN32
|
|
#define WAITACCESS_INITIAL 100
|
|
#define WAITACCESS_TIMEOUT 100000
|
|
|
|
SCODE WaitForAccess(ILockBytes *plst,
|
|
DFLAGS df,
|
|
ULONG *poReturn)
|
|
{
|
|
SCODE sc;
|
|
DWORD dwWait;
|
|
|
|
olDebugOut((DEB_ITRACE, "In WaitForAccess(%p, %X, %p)\n",
|
|
plst, df, poReturn));
|
|
|
|
dwWait = WAITACCESS_INITIAL;
|
|
for (;;)
|
|
{
|
|
sc = GetAccess(plst, df, poReturn);
|
|
if (sc != STG_E_LOCKVIOLATION ||
|
|
dwWait >= WAITACCESS_TIMEOUT
|
|
)
|
|
break;
|
|
|
|
Sleep(dwWait);
|
|
dwWait *= 2;
|
|
}
|
|
|
|
olDebugOut((DEB_ITRACE, "Out WaitForAccess => 0x%lX, %lu\n",
|
|
sc, poReturn));
|
|
return sc;
|
|
}
|
|
#endif
|