1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
/*-
* Copyright (c) 2008-2012 WiredTiger, Inc.
* All rights reserved.
*
* See the file LICENSE for redistribution information.
*/
#include "wt_internal.h"
/*
* __open_directory_sync:
* Fsync the directory in which we created the file.
*/
static int
__open_directory_sync(WT_SESSION_IMPL *session)
{
#ifdef __linux__
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
int fd;
conn = S2C(session);
/*
* According to the Linux fsync man page:
* Calling fsync() does not necessarily ensure that the entry in
* the directory containing the file has also reached disk. For
* that an explicit fsync() on a file descriptor for the directory
* is also needed.
*
* Open the WiredTiger home directory and sync it, I don't want the rest
* of the system to have to wonder if opening a file creates it.
*/
WT_SYSCALL_RETRY(((fd =
open(conn->home, O_RDONLY, 0444)) == -1 ? 1 : 0), ret);
if (ret != 0)
WT_RET_MSG(session, ret, "%s: open", conn->home);
WT_SYSCALL_RETRY(fsync(fd), ret);
if (ret != 0)
WT_ERR_MSG(session, ret, "%s: fsync", conn->home);
err: WT_SYSCALL_RETRY(close(fd), ret);
if (ret != 0)
WT_ERR_MSG(session, ret, "%s: close", conn->home);
#else
WT_UNUSED(session);
#endif
return (0);
}
/*
* __wt_open --
* Open a file handle.
*/
int
__wt_open(WT_SESSION_IMPL *session,
const char *name, int ok_create, int exclusive, int is_tree, WT_FH **fhp)
{
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
WT_FH *fh;
mode_t mode;
int f, fd, matched;
const char *path;
conn = S2C(session);
fh = NULL;
fd = -1;
WT_VERBOSE_RET(session, fileops, "%s: open", name);
/* Increment the reference count if we already have the file open. */
matched = 0;
__wt_spin_lock(session, &conn->fh_lock);
TAILQ_FOREACH(fh, &conn->fhqh, q) {
if (strcmp(name, fh->name) == 0) {
++fh->refcnt;
*fhp = fh;
matched = 1;
break;
}
}
__wt_spin_unlock(session, &conn->fh_lock);
if (matched)
return (0);
WT_RET(__wt_filename(session, name, &path));
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
if (ok_create) {
f |= O_CREAT;
if (exclusive)
f |= O_EXCL;
mode = 0666;
} else
mode = 0;
#ifdef O_DIRECT
if (is_tree && FLD_ISSET(conn->direct_io, WT_DIRECTIO_DATA))
f |= O_DIRECT;
#else
WT_UNUSED(is_tree);
#endif
WT_SYSCALL_RETRY(((fd = open(path, f, mode)) == -1 ? 1 : 0), ret);
if (ret != 0)
WT_ERR_MSG(session, ret, "%s", name);
#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 (is_tree)
WT_ERR(posix_fadvise(fd, 0, 0, POSIX_FADV_RANDOM));
#endif
WT_ERR(__open_directory_sync(session));
WT_ERR(__wt_calloc(session, 1, sizeof(WT_FH), &fh));
WT_ERR(__wt_strdup(session, name, &fh->name));
fh->fd = fd;
fh->refcnt = 1;
/* Set the file's size. */
WT_ERR(__wt_filesize(session, fh, &fh->file_size));
/* Link onto the environment's list of files. */
__wt_spin_lock(session, &conn->fh_lock);
TAILQ_INSERT_TAIL(&conn->fhqh, fh, q);
__wt_spin_unlock(session, &conn->fh_lock);
*fhp = fh;
if (0) {
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 *fh)
{
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
conn = S2C(session);
if (fh == NULL || fh->refcnt == 0 || --fh->refcnt > 0)
return (0);
/* Remove from the list and discard the memory. */
__wt_spin_lock(session, &conn->fh_lock);
TAILQ_REMOVE(&conn->fhqh, fh, q);
__wt_spin_unlock(session, &conn->fh_lock);
if (close(fh->fd) != 0) {
ret = __wt_errno();
__wt_err(session, ret, "%s", fh->name);
}
__wt_free(session, fh->name);
__wt_free(session, fh);
return (ret);
}
|
