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 return MEMCACHED_TIMEOUT
;
44 /* Imposssible for anything other then -1 */
45 WATCHPOINT_ASSERT(error
== -1);
46 memcached_quit_server(ptr
, server_key
, 1);
48 return MEMCACHED_FAILURE
;
52 void memcached_io_preread(memcached_st
*ptr
)
58 for (x
= 0; x
< ptr
->number_of_hosts
; x
++)
60 if (memcached_server_response_count(ptr
, x
) &&
61 ptr
->hosts
[x
].read_data_length
< MEMCACHED_MAX_BUFFER
)
65 data_read
= read(ptr
->hosts
[x
].fd
,
66 ptr
->hosts
[x
].read_ptr
+ ptr
->hosts
[x
].read_data_length
,
67 MEMCACHED_MAX_BUFFER
- ptr
->hosts
[x
].read_data_length
);
71 ptr
->hosts
[x
].read_buffer_length
+= data_read
;
72 ptr
->hosts
[x
].read_data_length
+= data_read
;
77 ssize_t
memcached_io_read(memcached_st
*ptr
, unsigned int server_key
,
78 char *buffer
, size_t length
)
86 if (!ptr
->hosts
[server_key
].read_buffer_length
)
92 data_read
= read(ptr
->hosts
[server_key
].fd
,
93 ptr
->hosts
[server_key
].read_buffer
,
94 MEMCACHED_MAX_BUFFER
);
103 rc
= io_wait(ptr
, server_key
, MEM_READ
);
105 if (rc
== MEMCACHED_SUCCESS
)
108 memcached_quit_server(ptr
, server_key
, 1);
113 memcached_quit_server(ptr
, server_key
, 1);
114 ptr
->cached_errno
= errno
;
121 /* If zero, just keep looping */
124 ptr
->hosts
[server_key
].read_data_length
= data_read
;
125 ptr
->hosts
[server_key
].read_buffer_length
= data_read
;
126 ptr
->hosts
[server_key
].read_ptr
= ptr
->hosts
[server_key
].read_buffer
;
133 difference
= (length
> ptr
->hosts
[server_key
].read_buffer_length
) ? ptr
->hosts
[server_key
].read_buffer_length
: length
;
135 memcpy(buffer_ptr
, ptr
->hosts
[server_key
].read_ptr
, difference
);
136 length
-= difference
;
137 ptr
->hosts
[server_key
].read_ptr
+= difference
;
138 ptr
->hosts
[server_key
].read_buffer_length
-= difference
;
139 buffer_ptr
+= difference
;
143 *buffer_ptr
= *ptr
->hosts
[server_key
].read_ptr
;
145 ptr
->hosts
[server_key
].read_ptr
++;
146 ptr
->hosts
[server_key
].read_buffer_length
--;
151 return (size_t)(buffer_ptr
- buffer
);
154 ssize_t
memcached_io_write(memcached_st
*ptr
, unsigned int server_key
,
155 char *buffer
, size_t length
, char with_flush
)
157 unsigned long long x
;
159 for (x
= 0; x
< length
; x
++)
161 if (ptr
->hosts
[server_key
].write_ptr
== 0)
162 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
163 WATCHPOINT_ASSERT(ptr
->hosts
[server_key
].write_ptr
);
164 *ptr
->hosts
[server_key
].write_ptr
= buffer
[x
];
165 ptr
->hosts
[server_key
].write_ptr
++;
166 ptr
->hosts
[server_key
].write_buffer_offset
++;
168 if (ptr
->hosts
[server_key
].write_buffer_offset
== MEMCACHED_MAX_BUFFER
)
173 sent_length
= io_flush(ptr
, server_key
, &rc
);
174 if (sent_length
== -1)
177 WATCHPOINT_ASSERT(sent_length
== MEMCACHED_MAX_BUFFER
);
178 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
179 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
186 if (io_flush(ptr
, server_key
, &rc
) == -1)
193 memcached_return
memcached_io_close(memcached_st
*ptr
, unsigned int server_key
)
195 close(ptr
->hosts
[server_key
].fd
);
197 return MEMCACHED_SUCCESS
;
200 static ssize_t
io_flush(memcached_st
*ptr
, unsigned int server_key
,
201 memcached_return
*error
)
204 size_t return_length
;
205 char *write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
206 size_t write_length
= ptr
->hosts
[server_key
].write_buffer_offset
;
208 *error
= MEMCACHED_SUCCESS
;
210 if (ptr
->hosts
[server_key
].write_buffer_offset
== 0)
217 if (ptr
->hosts
[server_key
].type
== MEMCACHED_CONNECTION_UDP
)
219 sent_length
= sendto(ptr
->hosts
[server_key
].fd
,
220 write_ptr
, write_length
, 0,
221 (struct sockaddr
*)&ptr
->hosts
[server_key
].address_info
->ai_addr
,
222 sizeof(struct sockaddr
));
226 if ((ssize_t
)(sent_length
= write(ptr
->hosts
[server_key
].fd
, write_ptr
,
227 write_length
)) == -1)
236 rc
= io_wait(ptr
, server_key
, MEM_WRITE
);
238 if (rc
== MEMCACHED_SUCCESS
)
241 memcached_quit_server(ptr
, server_key
, 1);
245 memcached_quit_server(ptr
, server_key
, 1);
246 ptr
->cached_errno
= errno
;
247 *error
= MEMCACHED_ERRNO
;
253 write_ptr
+= sent_length
;
254 write_length
-= sent_length
;
255 return_length
+= sent_length
;
258 WATCHPOINT_ASSERT(write_length
== 0);
259 WATCHPOINT_ASSERT(return_length
== ptr
->hosts
[server_key
].write_buffer_offset
);
260 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
261 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
263 return return_length
;
267 Eventually we will just kill off the server with the problem.
269 void memcached_io_reset(memcached_st
*ptr
, unsigned int server_key
)
271 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
272 ptr
->hosts
[server_key
].write_buffer_offset
= 0;