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);
47 return MEMCACHED_FAILURE
;
51 ssize_t
memcached_io_read(memcached_st
*ptr
, unsigned int server_key
,
52 char *buffer
, size_t length
)
60 if (!ptr
->hosts
[server_key
].read_buffer_length
)
66 data_read
= read(ptr
->hosts
[server_key
].fd
,
67 ptr
->hosts
[server_key
].read_buffer
,
68 MEMCACHED_MAX_BUFFER
);
76 rc
= io_wait(ptr
, server_key
, MEM_READ
);
78 if (rc
== MEMCACHED_SUCCESS
)
81 memcached_quit_server(ptr
, server_key
, 1);
86 memcached_quit_server(ptr
, server_key
, 1);
87 ptr
->cached_errno
= errno
;
94 /* If zero, just keep looping */
97 ptr
->hosts
[server_key
].read_buffer_length
= data_read
;
98 ptr
->hosts
[server_key
].read_ptr
= ptr
->hosts
[server_key
].read_buffer
;
101 *buffer_ptr
= *ptr
->hosts
[server_key
].read_ptr
;
103 ptr
->hosts
[server_key
].read_ptr
++;
104 ptr
->hosts
[server_key
].read_buffer_length
--;
108 return (size_t)(buffer_ptr
- buffer
);
111 ssize_t
memcached_io_write(memcached_st
*ptr
, unsigned int server_key
,
112 char *buffer
, size_t length
, char with_flush
)
114 unsigned long long x
;
116 for (x
= 0; x
< length
; x
++)
118 if (ptr
->hosts
[server_key
].write_ptr
== 0)
119 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
120 WATCHPOINT_ASSERT(ptr
->hosts
[server_key
].write_ptr
);
121 *ptr
->hosts
[server_key
].write_ptr
= buffer
[x
];
122 ptr
->hosts
[server_key
].write_ptr
++;
123 ptr
->hosts
[server_key
].write_buffer_offset
++;
125 if (ptr
->hosts
[server_key
].write_buffer_offset
== MEMCACHED_MAX_BUFFER
)
130 sent_length
= io_flush(ptr
, server_key
, &rc
);
131 if (sent_length
== -1)
134 WATCHPOINT_ASSERT(sent_length
== MEMCACHED_MAX_BUFFER
);
135 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
136 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
143 if (io_flush(ptr
, server_key
, &rc
) == -1)
150 memcached_return
memcached_io_close(memcached_st
*ptr
, unsigned int server_key
)
152 close(ptr
->hosts
[server_key
].fd
);
154 return MEMCACHED_SUCCESS
;
157 static ssize_t
io_flush(memcached_st
*ptr
, unsigned int server_key
,
158 memcached_return
*error
)
161 size_t return_length
;
162 char *write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
163 size_t write_length
= ptr
->hosts
[server_key
].write_buffer_offset
;
165 *error
= MEMCACHED_SUCCESS
;
167 if (ptr
->hosts
[server_key
].write_buffer_offset
== 0)
174 if (ptr
->hosts
[server_key
].type
== MEMCACHED_CONNECTION_UDP
)
176 sent_length
= sendto(ptr
->hosts
[server_key
].fd
,
177 write_ptr
, write_length
, 0,
178 (struct sockaddr
*)&ptr
->hosts
[server_key
].address_info
->ai_addr
,
179 sizeof(struct sockaddr
));
183 if ((ssize_t
)(sent_length
= write(ptr
->hosts
[server_key
].fd
, write_ptr
,
184 write_length
)) == -1)
193 rc
= io_wait(ptr
, server_key
, MEM_WRITE
);
195 if (rc
== MEMCACHED_SUCCESS
)
198 memcached_quit_server(ptr
, server_key
, 1);
202 memcached_quit_server(ptr
, server_key
, 1);
203 ptr
->cached_errno
= errno
;
204 *error
= MEMCACHED_ERRNO
;
210 write_ptr
+= sent_length
;
211 write_length
-= sent_length
;
212 return_length
+= sent_length
;
215 WATCHPOINT_ASSERT(write_length
== 0);
216 WATCHPOINT_ASSERT(return_length
== ptr
->hosts
[server_key
].write_buffer_offset
);
217 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
218 ptr
->hosts
[server_key
].write_buffer_offset
= 0;
220 return return_length
;
224 Eventually we will just kill off the server with the problem.
226 void memcached_io_reset(memcached_st
*ptr
, unsigned int server_key
)
228 ptr
->hosts
[server_key
].write_ptr
= ptr
->hosts
[server_key
].write_buffer
;
229 ptr
->hosts
[server_key
].write_buffer_offset
= 0;