2 Basic socket buffered IO
6 #include "memcached_io.h"
7 #include <sys/select.h>
15 static ssize_t
io_flush(memcached_st
*ptr
, unsigned int server_key
,
16 memcached_return
*error
);
18 static memcached_return
io_wait(memcached_st
*ptr
, unsigned int server_key
,
19 memc_read_or_write read_or_write
)
25 if (read_or_write
== MEM_WRITE
) /* write */
26 flags
= POLLOUT
| POLLERR
;
28 flags
= POLLIN
| POLLERR
;
30 memset(&fds
, 0, sizeof(struct pollfd
));
31 fds
[0].fd
= ptr
->hosts
[server_key
].fd
;
34 error
= poll(fds
, 1, ptr
->poll_timeout
);
37 return MEMCACHED_SUCCESS
;
40 WATCHPOINT_NUMBER(read_or_write
);
41 return MEMCACHED_TIMEOUT
;
45 /* Imposssible for anything other then -1 */
46 WATCHPOINT_ASSERT(error
== -1);
47 memcached_quit_server(ptr
, server_key
, 1);
48 return MEMCACHED_FAILURE
;
52 ssize_t
memcached_io_read(memcached_st
*ptr
, unsigned int server_key
,
53 char *buffer
, size_t length
)
61 if (!ptr
->hosts
[server_key
].read_buffer_length
)
67 data_read
= read(ptr
->hosts
[server_key
].fd
,
68 ptr
->hosts
[server_key
].read_buffer
,
69 MEMCACHED_MAX_BUFFER
);
77 rc
= io_wait(ptr
, server_key
, MEM_READ
);
79 if (rc
== MEMCACHED_SUCCESS
)
82 memcached_quit_server(ptr
, server_key
, 1);
87 memcached_quit_server(ptr
, server_key
, 1);
88 ptr
->cached_errno
= errno
;
95 /* If zero, just keep looping */
98 ptr
->hosts
[server_key
].read_buffer_length
= data_read
;
99 ptr
->hosts
[server_key
].read_ptr
= ptr
->hosts
[server_key
].read_buffer
;
102 *buffer_ptr
= *ptr
->hosts
[server_key
].read_ptr
;
104 ptr
->hosts
[server_key
].read_ptr
++;
105 ptr
->hosts
[server_key
].read_buffer_length
--;
109 return (size_t)(buffer_ptr
- buffer
);
112 ssize_t
memcached_io_write(memcached_st
*ptr
, unsigned int server_key
,
113 char *buffer
, size_t length
, char with_flush
)
115 unsigned long long x
;
117 for (x
= 0; x
< length
; x
++)
119 if (ptr
->hosts
[server_key
].write_ptr
== 0)
120 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
121 WATCHPOINT_ASSERT(ptr
->hosts
[server_key
].write_ptr
);
122 *ptr
->hosts
[server_key
].write_ptr
= buffer
[x
];
123 ptr
->hosts
[server_key
].write_ptr
++;
124 ptr
->hosts
[server_key
].write_buffer_offset
++;
126 if (ptr
->hosts
[server_key
].write_buffer_offset
== MEMCACHED_MAX_BUFFER
)
131 sent_length
= io_flush(ptr
, server_key
, &rc
);
132 if (sent_length
== -1)
135 WATCHPOINT_ASSERT(sent_length
== MEMCACHED_MAX_BUFFER
);
136 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
137 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
144 if (io_flush(ptr
, server_key
, &rc
) == -1)
151 memcached_return
memcached_io_close(memcached_st
*ptr
, unsigned int server_key
)
155 rc
= MEMCACHED_SUCCESS
;
156 if (ptr
->flags
& MEM_NO_BLOCK
)
159 struct pollfd fds
[1];
162 flags
= POLLHUP
| POLLERR
;
164 memset(&fds
, 0, sizeof(struct pollfd
));
165 fds
[0].fd
= ptr
->hosts
[server_key
].fd
;
166 fds
[0].events
= flags
;
169 error
= poll(fds
, 1, ptr
->poll_timeout
== -1 ? 100 : ptr
->poll_timeout
);
173 memcached_quit_server(ptr
, server_key
, 1);
174 return MEMCACHED_FAILURE
;
177 return MEMCACHED_FAILURE
; /* Timeout occurred */
180 close(ptr
->hosts
[server_key
].fd
);
185 static ssize_t
io_flush(memcached_st
*ptr
, unsigned int server_key
,
186 memcached_return
*error
)
189 size_t return_length
;
190 char *write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
191 size_t write_length
= ptr
->hosts
[server_key
].write_buffer_offset
;
193 *error
= MEMCACHED_SUCCESS
;
195 if (ptr
->hosts
[server_key
].write_buffer_offset
== 0)
202 if (ptr
->hosts
[server_key
].type
== MEMCACHED_CONNECTION_UDP
)
204 sent_length
= sendto(ptr
->hosts
[server_key
].fd
,
205 write_ptr
, write_length
, 0,
206 (struct sockaddr
*)&ptr
->hosts
[server_key
].address_info
->ai_addr
,
207 sizeof(struct sockaddr
));
211 if ((ssize_t
)(sent_length
= write(ptr
->hosts
[server_key
].fd
, write_ptr
,
212 write_length
)) == -1)
221 rc
= io_wait(ptr
, server_key
, MEM_WRITE
);
223 if (rc
== MEMCACHED_SUCCESS
)
226 memcached_quit_server(ptr
, server_key
, 1);
230 memcached_quit_server(ptr
, server_key
, 1);
231 ptr
->cached_errno
= errno
;
232 *error
= MEMCACHED_ERRNO
;
238 write_ptr
+= sent_length
;
239 write_length
-= sent_length
;
240 return_length
+= sent_length
;
243 WATCHPOINT_ASSERT(write_length
== 0);
244 WATCHPOINT_ASSERT(return_length
== ptr
->hosts
[server_key
].write_buffer_offset
);
245 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
246 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
248 return return_length
;
252 Eventually we will just kill off the server with the problem.
254 void memcached_io_reset(memcached_st
*ptr
, unsigned int server_key
)
256 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
257 ptr
->hosts
[server_key
].write_buffer_offset
= 0;