| Current Path : /usr/src/lib/libc/net/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libc/net/nscachedcli.c |
/*-
* Copyright (c) 2005 Michael Bushkov <bushman@rsu.ru>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/lib/libc/net/nscachedcli.c 164882 2006-12-04 17:08:43Z ume $");
#include "namespace.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/event.h>
#include <sys/uio.h>
#include <sys/un.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "un-namespace.h"
#include "nscachedcli.h"
#define NS_DEFAULT_CACHED_IO_TIMEOUT 4
static int safe_write(struct cached_connection_ *, const void *, size_t);
static int safe_read(struct cached_connection_ *, void *, size_t);
static int send_credentials(struct cached_connection_ *, int);
/*
* safe_write writes data to the specified connection and tries to do it in
* the very safe manner. We ensure, that we can write to the socket with
* kevent. If the data_size can't be sent in one piece, then it would be
* splitted.
*/
static int
safe_write(struct cached_connection_ *connection, const void *data,
size_t data_size)
{
struct kevent eventlist;
int nevents;
size_t result;
ssize_t s_result;
struct timespec timeout;
if (data_size == 0)
return (0);
timeout.tv_sec = NS_DEFAULT_CACHED_IO_TIMEOUT;
timeout.tv_nsec = 0;
result = 0;
do {
nevents = _kevent(connection->write_queue, NULL, 0, &eventlist,
1, &timeout);
if ((nevents == 1) && (eventlist.filter == EVFILT_WRITE)) {
s_result = _write(connection->sockfd, data + result,
eventlist.data < data_size - result ?
eventlist.data : data_size - result);
if (s_result == -1)
return (-1);
else
result += s_result;
if (eventlist.flags & EV_EOF)
return (result < data_size ? -1 : 0);
} else
return (-1);
} while (result < data_size);
return (0);
}
/*
* safe_read reads data from connection and tries to do it in the very safe
* and stable way. It uses kevent to ensure, that the data are availabe for
* reading. If the amount of data to be read is too large, then they would
* be splitted.
*/
static int
safe_read(struct cached_connection_ *connection, void *data, size_t data_size)
{
struct kevent eventlist;
size_t result;
ssize_t s_result;
struct timespec timeout;
int nevents;
if (data_size == 0)
return (0);
timeout.tv_sec = NS_DEFAULT_CACHED_IO_TIMEOUT;
timeout.tv_nsec = 0;
result = 0;
do {
nevents = _kevent(connection->read_queue, NULL, 0, &eventlist,
1, &timeout);
if (nevents == 1 && eventlist.filter == EVFILT_READ) {
s_result = _read(connection->sockfd, data + result,
eventlist.data <= data_size - result ?
eventlist.data : data_size - result);
if (s_result == -1)
return (-1);
else
result += s_result;
if (eventlist.flags & EV_EOF)
return (result < data_size ? -1 : 0);
} else
return (-1);
} while (result < data_size);
return (0);
}
/*
* Sends the credentials information to the connection along with the
* communication element type.
*/
static int
send_credentials(struct cached_connection_ *connection, int type)
{
struct kevent eventlist;
int nevents;
ssize_t result;
int res;
struct msghdr cred_hdr;
struct iovec iov;
struct {
struct cmsghdr hdr;
char cred[CMSG_SPACE(sizeof(struct cmsgcred))];
} cmsg;
memset(&cmsg, 0, sizeof(cmsg));
cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(struct cmsgcred));
cmsg.hdr.cmsg_level = SOL_SOCKET;
cmsg.hdr.cmsg_type = SCM_CREDS;
memset(&cred_hdr, 0, sizeof(struct msghdr));
cred_hdr.msg_iov = &iov;
cred_hdr.msg_iovlen = 1;
cred_hdr.msg_control = (caddr_t)&cmsg;
cred_hdr.msg_controllen = CMSG_SPACE(sizeof(struct cmsgcred));
iov.iov_base = &type;
iov.iov_len = sizeof(int);
EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
NOTE_LOWAT, sizeof(int), NULL);
res = _kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
nevents = _kevent(connection->write_queue, NULL, 0, &eventlist, 1,
NULL);
if (nevents == 1 && eventlist.filter == EVFILT_WRITE) {
result = (_sendmsg(connection->sockfd, &cred_hdr, 0) == -1) ?
-1 : 0;
EV_SET(&eventlist, connection->sockfd, EVFILT_WRITE, EV_ADD,
0, 0, NULL);
_kevent(connection->write_queue, &eventlist, 1, NULL, 0, NULL);
return (result);
} else
return (-1);
}
/*
* Opens the connection with the specified params. Initializes all kqueues.
*/
struct cached_connection_ *
__open_cached_connection(struct cached_connection_params const *params)
{
struct cached_connection_ *retval;
struct kevent eventlist;
struct sockaddr_un client_address;
int client_address_len, client_socket;
int res;
assert(params != NULL);
client_socket = _socket(PF_LOCAL, SOCK_STREAM, 0);
client_address.sun_family = PF_LOCAL;
strncpy(client_address.sun_path, params->socket_path,
sizeof(client_address.sun_path));
client_address_len = sizeof(client_address.sun_family) +
strlen(client_address.sun_path) + 1;
res = _connect(client_socket, (struct sockaddr *)&client_address,
client_address_len);
if (res == -1) {
_close(client_socket);
return (NULL);
}
_fcntl(client_socket, F_SETFL, O_NONBLOCK);
retval = malloc(sizeof(struct cached_connection_));
assert(retval != NULL);
memset(retval, 0, sizeof(struct cached_connection_));
retval->sockfd = client_socket;
retval->write_queue = kqueue();
assert(retval->write_queue != -1);
EV_SET(&eventlist, retval->sockfd, EVFILT_WRITE, EV_ADD, 0, 0, NULL);
res = _kevent(retval->write_queue, &eventlist, 1, NULL, 0, NULL);
retval->read_queue = kqueue();
assert(retval->read_queue != -1);
EV_SET(&eventlist, retval->sockfd, EVFILT_READ, EV_ADD, 0, 0, NULL);
res = _kevent(retval->read_queue, &eventlist, 1, NULL, 0, NULL);
return (retval);
}
void
__close_cached_connection(struct cached_connection_ *connection)
{
assert(connection != NULL);
_close(connection->sockfd);
_close(connection->read_queue);
_close(connection->write_queue);
free(connection);
}
/*
* This function is very close to the cache_write function of the caching
* library, which is used in the caching daemon. It caches the data with the
* specified key in the cache entry with entry_name.
*/
int
__cached_write(struct cached_connection_ *connection, const char *entry_name,
const char *key, size_t key_size, const char *data, size_t data_size)
{
size_t name_size;
int error_code;
int result;
error_code = -1;
result = 0;
result = send_credentials(connection, CET_WRITE_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &key_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &data_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_write(connection, key, key_size);
if (result != 0)
goto fin;
result = safe_write(connection, data, data_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
error_code = -1;
fin:
return (error_code);
}
/*
* This function is very close to the cache_read function of the caching
* library, which is used in the caching daemon. It reads cached data with the
* specified key from the cache entry with entry_name.
*/
int
__cached_read(struct cached_connection_ *connection, const char *entry_name,
const char *key, size_t key_size, char *data, size_t *data_size)
{
size_t name_size, result_size;
int error_code, rec_error_code;
int result;
assert(connection != NULL);
result = 0;
error_code = -1;
result = send_credentials(connection, CET_READ_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, &key_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_write(connection, key, key_size);
if (result != 0)
goto fin;
result = safe_read(connection, &rec_error_code, sizeof(int));
if (result != 0)
goto fin;
if (rec_error_code != 0) {
error_code = rec_error_code;
goto fin;
}
result = safe_read(connection, &result_size, sizeof(size_t));
if (result != 0)
goto fin;
if (result_size > *data_size) {
*data_size = result_size;
error_code = -2;
goto fin;
}
result = safe_read(connection, data, result_size);
if (result != 0)
goto fin;
*data_size = result_size;
error_code = 0;
fin:
return (error_code);
}
/*
* Initializes the mp_write_session. For such a session the new connection
* would be opened. The data should be written to the session with
* __cached_mp_write function. The __close_cached_mp_write_session function
* should be used to submit session and __abandon_cached_mp_write_session - to
* abandon it. When the session is submitted, the whole se
*/
struct cached_connection_ *
__open_cached_mp_write_session(struct cached_connection_params const *params,
const char *entry_name)
{
struct cached_connection_ *connection, *retval;
size_t name_size;
int error_code;
int result;
retval = NULL;
connection = __open_cached_connection(params);
if (connection == NULL)
return (NULL);
connection->mp_flag = 1;
result = send_credentials(connection, CET_MP_WRITE_SESSION_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
goto fin;
if (error_code != 0)
result = error_code;
fin:
if (result != 0)
__close_cached_connection(connection);
else
retval = connection;
return (retval);
}
/*
* Adds new portion of data to the opened write session
*/
int
__cached_mp_write(struct cached_connection_ *ws, const char *data,
size_t data_size)
{
int request, result;
int error_code;
error_code = -1;
request = CET_MP_WRITE_SESSION_WRITE_REQUEST;
result = safe_write(ws, &request, sizeof(int));
if (result != 0)
goto fin;
result = safe_write(ws, &data_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(ws, data, data_size);
if (result != 0)
goto fin;
result = safe_read(ws, &error_code, sizeof(int));
if (result != 0)
error_code = -1;
fin:
return (error_code);
}
/*
* Abandons all operations with the write session. All data, that were written
* to the session before, are discarded.
*/
int
__abandon_cached_mp_write_session(struct cached_connection_ *ws)
{
int notification;
int result;
notification = CET_MP_WRITE_SESSION_ABANDON_NOTIFICATION;
result = safe_write(ws, ¬ification, sizeof(int));
__close_cached_connection(ws);
return (result);
}
/*
* Gracefully closes the write session. The data, that were previously written
* to the session, are committed.
*/
int
__close_cached_mp_write_session(struct cached_connection_ *ws)
{
int notification;
int result;
notification = CET_MP_WRITE_SESSION_CLOSE_NOTIFICATION;
result = safe_write(ws, ¬ification, sizeof(int));
__close_cached_connection(ws);
return (0);
}
struct cached_connection_ *
__open_cached_mp_read_session(struct cached_connection_params const *params,
const char *entry_name)
{
struct cached_connection_ *connection, *retval;
size_t name_size;
int error_code;
int result;
retval = NULL;
connection = __open_cached_connection(params);
if (connection == NULL)
return (NULL);
connection->mp_flag = 1;
result = send_credentials(connection, CET_MP_READ_SESSION_REQUEST);
if (result != 0)
goto fin;
name_size = strlen(entry_name);
result = safe_write(connection, &name_size, sizeof(size_t));
if (result != 0)
goto fin;
result = safe_write(connection, entry_name, name_size);
if (result != 0)
goto fin;
result = safe_read(connection, &error_code, sizeof(int));
if (result != 0)
goto fin;
if (error_code != 0)
result = error_code;
fin:
if (result != 0)
__close_cached_connection(connection);
else
retval = connection;
return (retval);
}
int
__cached_mp_read(struct cached_connection_ *rs, char *data, size_t *data_size)
{
size_t result_size;
int error_code, rec_error_code;
int request, result;
error_code = -1;
request = CET_MP_READ_SESSION_READ_REQUEST;
result = safe_write(rs, &request, sizeof(int));
if (result != 0)
goto fin;
result = safe_read(rs, &rec_error_code, sizeof(int));
if (result != 0)
goto fin;
if (rec_error_code != 0) {
error_code = rec_error_code;
goto fin;
}
result = safe_read(rs, &result_size, sizeof(size_t));
if (result != 0)
goto fin;
if (result_size > *data_size) {
*data_size = result_size;
error_code = -2;
goto fin;
}
result = safe_read(rs, data, result_size);
if (result != 0)
goto fin;
*data_size = result_size;
error_code = 0;
fin:
return (error_code);
}
int
__close_cached_mp_read_session(struct cached_connection_ *rs)
{
__close_cached_connection(rs);
return (0);
}