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/*-
* Copyright (c) 2014-2016 MongoDB, Inc.
* Copyright (c) 2008-2014 WiredTiger, Inc.
* All rights reserved.
*
* See the file LICENSE for redistribution information.
*/
#include "wt_internal.h"
/*
* __wt_win_map --
* Map a file into memory.
*/
int
__wt_win_map(WT_SESSION_IMPL *session,
WT_FH *fh, void *mapp, size_t *lenp, void **mappingcookie)
{
WT_DECL_RET;
size_t len;
wt_off_t file_size;
void *map;
/*
* There's no locking here to prevent the underlying file from changing
* underneath us, our caller needs to ensure consistency of the mapped
* region vs. any other file activity.
*/
WT_RET(__wt_filesize(session, fh, &file_size));
len = (size_t)file_size;
(void)__wt_verbose(session, WT_VERB_HANDLEOPS,
"%s: memory-map: %" WT_SIZET_FMT " bytes", fh->name, len);
*mappingcookie =
CreateFileMappingA(fh->filehandle, NULL, PAGE_READONLY, 0, 0, NULL);
if (*mappingcookie == NULL)
WT_RET_MSG(session, __wt_getlasterror(),
"%s: memory-map: CreateFileMappingA", fh->name);
if ((map =
MapViewOfFile(*mappingcookie, FILE_MAP_READ, 0, 0, len)) == NULL) {
/* Retrieve the error before cleaning up. */
ret = __wt_getlasterror();
CloseHandle(*mappingcookie);
*mappingcookie = NULL;
WT_RET_MSG(session, ret,
"%s: memory-map: MapViewOfFile", fh->name);
}
*(void **)mapp = map;
*lenp = len;
return (0);
}
/*
* __wt_win_map_preload --
* Cause a section of a memory map to be faulted in.
*/
int
__wt_win_map_preload(
WT_SESSION_IMPL *session, WT_FH *fh, const void *p, size_t size)
{
WT_UNUSED(session);
WT_UNUSED(fh);
WT_UNUSED(p);
WT_UNUSED(size);
return (ENOTSUP);
}
/*
* __wt_win_map_discard --
* Discard a chunk of the memory map.
*/
int
__wt_win_map_discard(WT_SESSION_IMPL *session, WT_FH *fh, void *p, size_t size)
{
WT_UNUSED(session);
WT_UNUSED(fh);
WT_UNUSED(p);
WT_UNUSED(size);
return (ENOTSUP);
}
/*
* __wt_win_map_unmap --
* Remove a memory mapping.
*/
int
__wt_win_map_unmap(WT_SESSION_IMPL *session,
WT_FH *fh, void *map, size_t len, void **mappingcookie)
{
WT_DECL_RET;
(void)__wt_verbose(session, WT_VERB_HANDLEOPS,
"%s: memory-unmap: %" WT_SIZET_FMT " bytes", fh->name, len);
WT_ASSERT(session, *mappingcookie != NULL);
if (UnmapViewOfFile(map) == 0) {
ret = __wt_getlasterror();
__wt_err(session, ret,
"%s: memory-unmap: UnmapViewOfFile", fh->name);
}
if (CloseHandle(*mappingcookie) == 0) {
ret = __wt_getlasterror();
__wt_err(session, ret,
"%s: memory-unmap: CloseHandle", fh->name);
}
*mappingcookie = NULL;
return (ret);
}
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