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-rw-r--r--src/os_windows/os_open.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/src/os_windows/os_open.c b/src/os_windows/os_open.c
new file mode 100644
index 00000000..44f2faf3
--- /dev/null
+++ b/src/os_windows/os_open.c
@@ -0,0 +1,258 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1997, 2012 Oracle and/or its affiliates. All rights reserved.
+ *
+ * $Id$
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+
+/*
+ * __os_open --
+ * Open a file descriptor (including page size and log size information).
+ */
+int
+__os_open(env, name, page_size, flags, mode, fhpp)
+ ENV *env;
+ const char *name;
+ u_int32_t page_size, flags;
+ int mode;
+ DB_FH **fhpp;
+{
+ DB_ENV *dbenv;
+ DB_FH *fhp;
+#ifndef DB_WINCE
+ DWORD cluster_size, sector_size, free_clusters, total_clusters;
+ _TCHAR *drive, dbuf[4]; /* <letter><colon><slash><nul> */
+
+#endif
+ int access, attr, createflag, nrepeat, ret, share;
+ _TCHAR *tname;
+
+ dbenv = env == NULL ? NULL : env->dbenv;
+ *fhpp = NULL;
+ tname = NULL;
+
+ if (dbenv != NULL &&
+ FLD_ISSET(dbenv->verbose, DB_VERB_FILEOPS | DB_VERB_FILEOPS_ALL))
+ __db_msg(env, DB_STR_A("0025", "fileops: open %s",
+ "%s"), name);
+
+#undef OKFLAGS
+#define OKFLAGS \
+ (DB_OSO_ABSMODE | DB_OSO_CREATE | DB_OSO_DIRECT | DB_OSO_DSYNC |\
+ DB_OSO_EXCL | DB_OSO_RDONLY | DB_OSO_REGION | DB_OSO_SEQ | \
+ DB_OSO_TEMP | DB_OSO_TRUNC)
+ if ((ret = __db_fchk(env, "__os_open", flags, OKFLAGS)) != 0)
+ return (ret);
+
+ TO_TSTRING(env, name, tname, ret);
+ if (ret != 0)
+ goto err;
+
+ /*
+ * Allocate the file handle and copy the file name. We generally only
+ * use the name for verbose or error messages, but on systems where we
+ * can't unlink temporary files immediately, we use the name to unlink
+ * the temporary file when the file handle is closed.
+ *
+ * Lock the ENV handle and insert the new file handle on the list.
+ */
+ if ((ret = __os_calloc(env, 1, sizeof(DB_FH), &fhp)) != 0)
+ return (ret);
+ if ((ret = __os_strdup(env, name, &fhp->name)) != 0)
+ goto err;
+ if (env != NULL) {
+ MUTEX_LOCK(env, env->mtx_env);
+ TAILQ_INSERT_TAIL(&env->fdlist, fhp, q);
+ MUTEX_UNLOCK(env, env->mtx_env);
+ F_SET(fhp, DB_FH_ENVLINK);
+ }
+
+ /*
+ * Otherwise, use the Windows/32 CreateFile interface so that we can
+ * play magic games with files to get data flush effects similar to
+ * the POSIX O_DSYNC flag.
+ *
+ * !!!
+ * We currently ignore the 'mode' argument. It would be possible
+ * to construct a set of security attributes that we could pass to
+ * CreateFile that would accurately represents the mode. In worst
+ * case, this would require looking up user and all group names and
+ * creating an entry for each. Alternatively, we could call the
+ * _chmod (partial emulation) function after file creation, although
+ * this leaves us with an obvious race. However, these efforts are
+ * largely meaningless on FAT, the most common file system, which
+ * only has a "readable" and "writable" flag, applying to all users.
+ */
+ access = GENERIC_READ;
+ if (!LF_ISSET(DB_OSO_RDONLY))
+ access |= GENERIC_WRITE;
+
+#ifdef DB_WINCE
+ /*
+ * WinCE translates these flags into share flags for
+ * CreateFileForMapping.
+ * Also WinCE does not support the FILE_SHARE_DELETE flag.
+ */
+ if (LF_ISSET(DB_OSO_REGION))
+ share = GENERIC_READ | GENERIC_WRITE;
+ else
+ share = FILE_SHARE_READ | FILE_SHARE_WRITE;
+#else
+ share = FILE_SHARE_READ | FILE_SHARE_WRITE;
+ if (__os_is_winnt())
+ share |= FILE_SHARE_DELETE;
+#endif
+ attr = FILE_ATTRIBUTE_NORMAL;
+
+ /*
+ * Reproduce POSIX 1003.1 semantics: if O_CREATE and O_EXCL are both
+ * specified, fail, returning EEXIST, unless we create the file.
+ */
+ if (LF_ISSET(DB_OSO_CREATE) && LF_ISSET(DB_OSO_EXCL))
+ createflag = CREATE_NEW; /* create only if !exist*/
+ else if (!LF_ISSET(DB_OSO_CREATE) && LF_ISSET(DB_OSO_TRUNC))
+ createflag = TRUNCATE_EXISTING; /* truncate, fail if !exist */
+ else if (LF_ISSET(DB_OSO_TRUNC))
+ createflag = CREATE_ALWAYS; /* create and truncate */
+ else if (LF_ISSET(DB_OSO_CREATE))
+ createflag = OPEN_ALWAYS; /* open or create */
+ else
+ createflag = OPEN_EXISTING; /* open only if existing */
+
+ if (LF_ISSET(DB_OSO_DSYNC)) {
+ F_SET(fhp, DB_FH_NOSYNC);
+ attr |= FILE_FLAG_WRITE_THROUGH;
+ }
+
+#ifndef DB_WINCE
+ if (LF_ISSET(DB_OSO_SEQ))
+ attr |= FILE_FLAG_SEQUENTIAL_SCAN;
+ else
+ attr |= FILE_FLAG_RANDOM_ACCESS;
+#endif
+
+ if (LF_ISSET(DB_OSO_TEMP))
+ attr |= FILE_FLAG_DELETE_ON_CLOSE;
+
+ /*
+ * We can turn filesystem buffering off if the page size is a
+ * multiple of the disk's sector size. To find the sector size,
+ * we call GetDiskFreeSpace, which expects a drive name like "d:\\"
+ * or NULL for the current disk (i.e., a relative path).
+ *
+ * WinCE only has GetDiskFreeSpaceEx which does not
+ * return the sector size.
+ */
+#ifndef DB_WINCE
+ if (LF_ISSET(DB_OSO_DIRECT) && page_size != 0 && name[0] != '\0') {
+ if (name[1] == ':') {
+ drive = dbuf;
+ _sntprintf(dbuf, sizeof(dbuf), _T("%c:\\"), tname[0]);
+ } else
+ drive = NULL;
+
+ /*
+ * We ignore all results except sectorsize, but some versions
+ * of Windows require that the parameters are non-NULL.
+ */
+ if (GetDiskFreeSpace(drive, &cluster_size,
+ &sector_size, &free_clusters, &total_clusters) &&
+ page_size % sector_size == 0)
+ attr |= FILE_FLAG_NO_BUFFERING;
+ }
+#endif
+
+ fhp->handle = fhp->trunc_handle = INVALID_HANDLE_VALUE;
+ for (nrepeat = 1;; ++nrepeat) {
+ if (fhp->handle == INVALID_HANDLE_VALUE) {
+#ifdef DB_WINCE
+ if (LF_ISSET(DB_OSO_REGION))
+ fhp->handle = CreateFileForMapping(tname,
+ access, share, NULL, createflag, attr, 0);
+ else
+#endif
+ fhp->handle = CreateFile(tname,
+ access, share, NULL, createflag, attr, 0);
+ }
+
+#ifdef HAVE_FTRUNCATE
+ /*
+ * Older versions of WinCE may not support truncate, if so, the
+ * HAVE_FTRUNCATE macro should be #undef'ed, and we
+ * don't need to open this second handle.
+ *
+ * WinCE dose not support opening a second handle on the same
+ * file via CreateFileForMapping, but this dose not matter
+ * since we are not truncating region files but database files.
+ *
+ * But some older versions of WinCE even
+ * dose not allow a second handle opened via CreateFile. If
+ * this is the case, users will need to #undef the
+ * HAVE_FTRUNCATE macro in build_wince/db_config.h.
+ */
+
+ /*
+ * Windows does not provide truncate directly. There is no
+ * safe way to use a handle for truncate concurrently with
+ * reads or writes. To deal with this, we open a second handle
+ * used just for truncating.
+ */
+ if (fhp->handle != INVALID_HANDLE_VALUE &&
+ !LF_ISSET(DB_OSO_RDONLY | DB_OSO_TEMP) &&
+ fhp->trunc_handle == INVALID_HANDLE_VALUE
+#ifdef DB_WINCE
+ /* Do not open trunc handle for region files. */
+ && (!LF_ISSET(DB_OSO_REGION))
+#endif
+ )
+ fhp->trunc_handle = CreateFile(
+ tname, access, share, NULL, OPEN_EXISTING, attr, 0);
+#endif
+
+#ifndef HAVE_FTRUNCATE
+ if (fhp->handle == INVALID_HANDLE_VALUE)
+#else
+ if (fhp->handle == INVALID_HANDLE_VALUE ||
+ (!LF_ISSET(DB_OSO_RDONLY | DB_OSO_TEMP) &&
+ fhp->trunc_handle == INVALID_HANDLE_VALUE
+#ifdef DB_WINCE
+ /* Do not open trunc handle for region files. */
+ && (!LF_ISSET(DB_OSO_REGION))
+#endif
+ ))
+#endif
+ {
+ /*
+ * If it's a "temporary" error, we retry up to 3 times,
+ * waiting up to 12 seconds. While it's not a problem
+ * if we can't open a database, an inability to open a
+ * log file is cause for serious dismay.
+ */
+ ret = __os_posix_err(__os_get_syserr());
+ if ((ret != ENFILE && ret != EMFILE && ret != ENOSPC) ||
+ nrepeat > 3)
+ goto err;
+
+ __os_yield(env, nrepeat * 2, 0);
+ } else
+ break;
+ }
+
+ FREE_STRING(env, tname);
+
+ if (LF_ISSET(DB_OSO_REGION))
+ F_SET(fhp, DB_FH_REGION);
+ F_SET(fhp, DB_FH_OPENED);
+ *fhpp = fhp;
+ return (0);
+
+err: FREE_STRING(env, tname);
+ if (fhp != NULL)
+ (void)__os_closehandle(env, fhp);
+ return (ret);
+}
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