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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"
/*
* __open_directory --
* Open up a file handle to a directory.
*/
static int
__open_directory(WT_SESSION_IMPL *session, char *path, int *fd)
{
WT_DECL_RET;
WT_SYSCALL_RETRY(((*fd =
open(path, O_RDONLY, 0444)) == -1 ? 1 : 0), ret);
if (ret != 0)
WT_RET_MSG(session, ret, "%s: open_directory", path);
return (ret);
}
/*
* __wt_open --
* Open a file handle.
*/
int
__wt_open(WT_SESSION_IMPL *session,
const char *name, bool ok_create, bool exclusive, int dio_type, WT_FH **fhp)
{
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
WT_FH *fh, *tfh;
mode_t mode;
uint64_t bucket, hash;
int f, fd;
bool direct_io, matched;
char *path;
conn = S2C(session);
direct_io = false;
fh = NULL;
fd = -1;
path = NULL;
WT_RET(__wt_verbose(session, WT_VERB_FILEOPS, "%s: open", name));
/* Increment the reference count if we already have the file open. */
matched = false;
hash = __wt_hash_city64(name, strlen(name));
bucket = hash % WT_HASH_ARRAY_SIZE;
__wt_spin_lock(session, &conn->fh_lock);
TAILQ_FOREACH(tfh, &conn->fhhash[bucket], hashq) {
if (strcmp(name, tfh->name) == 0) {
++tfh->ref;
*fhp = tfh;
matched = true;
break;
}
}
__wt_spin_unlock(session, &conn->fh_lock);
if (matched)
return (0);
WT_RET(__wt_filename(session, name, &path));
if (dio_type == WT_FILE_TYPE_DIRECTORY) {
WT_ERR(__open_directory(session, path, &fd));
goto setupfh;
}
f = O_RDWR;
#ifdef O_BINARY
/* Windows clones: we always want to treat the file as a binary. */
f |= O_BINARY;
#endif
#ifdef O_CLOEXEC
/*
* Security:
* The application may spawn a new process, and we don't want another
* process to have access to our file handles.
*/
f |= O_CLOEXEC;
#endif
#ifdef O_NOATIME
/* Avoid updating metadata for read-only workloads. */
if (dio_type == WT_FILE_TYPE_DATA ||
dio_type == WT_FILE_TYPE_CHECKPOINT)
f |= O_NOATIME;
#endif
if (ok_create) {
f |= O_CREAT;
if (exclusive)
f |= O_EXCL;
mode = 0666;
} else
mode = 0;
#ifdef O_DIRECT
if (dio_type && FLD_ISSET(conn->direct_io, dio_type)) {
f |= O_DIRECT;
direct_io = true;
}
#endif
if (dio_type == WT_FILE_TYPE_LOG &&
FLD_ISSET(conn->txn_logsync, WT_LOG_DSYNC))
#ifdef O_DSYNC
f |= O_DSYNC;
#elif defined(O_SYNC)
f |= O_SYNC;
#else
WT_ERR_MSG(session, ENOTSUP,
"Unsupported log sync mode requested");
#endif
WT_SYSCALL_RETRY(((fd = open(path, f, mode)) == -1 ? 1 : 0), ret);
if (ret != 0)
WT_ERR_MSG(session, ret,
direct_io ?
"%s: open failed with direct I/O configured, some "
"filesystem types do not support direct I/O" : "%s", path);
setupfh:
#if defined(HAVE_FCNTL) && defined(FD_CLOEXEC) && !defined(O_CLOEXEC)
/*
* Security:
* The application may spawn a new process, and we don't want another
* process to have access to our file handles. There's an obvious
* race here, so we prefer the flag to open if available.
*/
if ((f = fcntl(fd, F_GETFD)) == -1 ||
fcntl(fd, F_SETFD, f | FD_CLOEXEC) == -1)
WT_ERR_MSG(session, __wt_errno(), "%s: fcntl", name);
#endif
#if defined(HAVE_POSIX_FADVISE)
/* Disable read-ahead on trees: it slows down random read workloads. */
if (dio_type == WT_FILE_TYPE_DATA ||
dio_type == WT_FILE_TYPE_CHECKPOINT)
WT_ERR(posix_fadvise(fd, 0, 0, POSIX_FADV_RANDOM));
#endif
WT_ERR(__wt_calloc_one(session, &fh));
WT_ERR(__wt_strdup(session, name, &fh->name));
fh->name_hash = hash;
fh->fd = fd;
fh->ref = 1;
fh->direct_io = direct_io;
/* Set the file's size. */
WT_ERR(__wt_filesize(session, fh, &fh->size));
/* Configure file extension. */
if (dio_type == WT_FILE_TYPE_DATA ||
dio_type == WT_FILE_TYPE_CHECKPOINT)
fh->extend_len = conn->data_extend_len;
/* Configure fallocate/posix_fallocate calls. */
__wt_fallocate_config(session, fh);
/*
* Repeat the check for a match, but then link onto the database's list
* of files.
*/
matched = false;
__wt_spin_lock(session, &conn->fh_lock);
TAILQ_FOREACH(tfh, &conn->fhhash[bucket], hashq) {
if (strcmp(name, tfh->name) == 0) {
++tfh->ref;
*fhp = tfh;
matched = true;
break;
}
}
if (!matched) {
WT_CONN_FILE_INSERT(conn, fh, bucket);
(void)__wt_atomic_add32(&conn->open_file_count, 1);
*fhp = fh;
}
__wt_spin_unlock(session, &conn->fh_lock);
if (matched) {
err: if (fh != NULL) {
__wt_free(session, fh->name);
__wt_free(session, fh);
}
if (fd != -1)
(void)close(fd);
}
__wt_free(session, path);
return (ret);
}
/*
* __wt_close --
* Close a file handle.
*/
int
__wt_close(WT_SESSION_IMPL *session, WT_FH **fhp)
{
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
WT_FH *fh;
uint64_t bucket;
conn = S2C(session);
if (*fhp == NULL)
return (0);
fh = *fhp;
*fhp = NULL;
WT_RET(__wt_verbose(session, WT_VERB_FILEOPS, "%s: close", fh->name));
__wt_spin_lock(session, &conn->fh_lock);
if (fh == NULL || fh->ref == 0 || --fh->ref > 0) {
__wt_spin_unlock(session, &conn->fh_lock);
return (0);
}
/* Remove from the list. */
bucket = fh->name_hash % WT_HASH_ARRAY_SIZE;
WT_CONN_FILE_REMOVE(conn, fh, bucket);
(void)__wt_atomic_sub32(&conn->open_file_count, 1);
__wt_spin_unlock(session, &conn->fh_lock);
/* Discard the memory. */
if (close(fh->fd) != 0) {
ret = __wt_errno();
__wt_err(session, ret, "close: %s", fh->name);
}
__wt_free(session, fh->name);
__wt_free(session, fh);
return (ret);
}
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