typedef enum {
MEM_READ,
- MEM_WRITE,
+ MEM_WRITE
} memc_read_or_write;
static ssize_t io_flush(memcached_server_st *ptr, memcached_return *error);
static memcached_return io_wait(memcached_server_st *ptr,
memc_read_or_write read_or_write)
{
- struct pollfd fds[1];
- short flags= 0;
+ struct pollfd fds= {
+ .fd= ptr->fd,
+ .events = POLLIN
+ };
int error;
- if (read_or_write == MEM_WRITE) /* write */
- flags= POLLOUT | POLLERR;
- else
- flags= POLLIN | POLLERR;
-
- memset(&fds, 0, sizeof(struct pollfd));
- fds[0].fd= ptr->fd;
- fds[0].events= flags;
+ unlikely (read_or_write == MEM_WRITE) /* write */
+ fds.events= POLLOUT;
/*
** We are going to block on write, but at least on Solaris we might block
*/
if (read_or_write == MEM_WRITE)
{
- memcached_return rc=memcached_purge(ptr);
+ memcached_return rc= memcached_purge(ptr);
if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_STORED)
- return MEMCACHED_FAILURE;
+ return MEMCACHED_FAILURE;
}
- error= poll(fds, 1, ptr->root->poll_timeout);
+ int timeout= ptr->root->poll_timeout;
+ if ((ptr->root->flags & MEM_NO_BLOCK) == 0)
+ timeout= -1;
+
+ error= poll(&fds, 1, timeout);
if (error == 1)
return MEMCACHED_SUCCESS;
else if (error == 0)
- {
return MEMCACHED_TIMEOUT;
- }
/* Imposssible for anything other then -1 */
WATCHPOINT_ASSERT(error == -1);
memcached_quit_server(ptr, 1);
return MEMCACHED_FAILURE;
+}
+
+/**
+ * Try to fill the input buffer for a server with as much
+ * data as possible.
+ *
+ * @param ptr the server to pack
+ */
+static bool repack_input_buffer(memcached_server_st *ptr)
+{
+ if (ptr->read_ptr != ptr->read_buffer)
+ {
+ /* Move all of the data to the beginning of the buffer so
+ ** that we can fit more data into the buffer...
+ */
+ memmove(ptr->read_buffer, ptr->read_ptr, ptr->read_buffer_length);
+ ptr->read_ptr= ptr->read_buffer;
+ ptr->read_data_length= ptr->read_buffer_length;
+ }
+
+ /* There is room in the buffer, try to fill it! */
+ if (ptr->read_buffer_length != MEMCACHED_MAX_BUFFER)
+ {
+ /* Just try a single read to grab what's available */
+ ssize_t nr= read(ptr->fd,
+ ptr->read_ptr + ptr->read_data_length,
+ MEMCACHED_MAX_BUFFER - ptr->read_data_length);
+
+ if (nr > 0)
+ {
+ ptr->read_data_length+= (size_t)nr;
+ ptr->read_buffer_length+= (size_t)nr;
+ return true;
+ }
+ }
+ return false;
+}
+
+/**
+ * If the we have callbacks connected to this server structure
+ * we may start process the input queue and fire the callbacks
+ * for the incomming messages. This function is _only_ called
+ * when the input buffer is full, so that we _know_ that we have
+ * at least _one_ message to process.
+ *
+ * @param ptr the server to star processing iput messages for
+ * @return true if we processed anything, false otherwise
+ */
+static bool process_input_buffer(memcached_server_st *ptr)
+{
+ /*
+ ** We might be able to process some of the response messages if we
+ ** have a callback set up
+ */
+ if (ptr->root->callbacks != NULL && (ptr->root->flags & MEM_USE_UDP) == 0)
+ {
+ /*
+ * We might have responses... try to read them out and fire
+ * callbacks
+ */
+ memcached_callback_st cb= *ptr->root->callbacks;
+
+ char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
+ memcached_return error;
+ error= memcached_response(ptr, buffer, sizeof(buffer),
+ &ptr->root->result);
+ if (error == MEMCACHED_SUCCESS)
+ {
+ for (unsigned int x= 0; x < cb.number_of_callback; x++)
+ {
+ error= (*cb.callback[x])(ptr->root, &ptr->root->result, cb.context);
+ if (error != MEMCACHED_SUCCESS)
+ break;
+ }
+ /* @todo what should I do with the error message??? */
+ }
+ /* @todo what should I do with other error messages?? */
+ return true;
+ }
+
+ return false;
}
#ifdef UNUSED
}
#endif
-ssize_t memcached_io_read(memcached_server_st *ptr,
- void *buffer, size_t length)
+memcached_return memcached_io_read(memcached_server_st *ptr,
+ void *buffer, size_t length, ssize_t *nread)
{
char *buffer_ptr;
while (1)
{
- data_read= read(ptr->fd,
- ptr->read_buffer,
- MEMCACHED_MAX_BUFFER);
+ data_read= read(ptr->fd, ptr->read_buffer, MEMCACHED_MAX_BUFFER);
if (data_read > 0)
break;
else if (data_read == -1)
{
ptr->cached_errno= errno;
+ memcached_return rc= MEMCACHED_UNKNOWN_READ_FAILURE;
switch (errno)
{
case EAGAIN:
- case EINTR:
- {
- memcached_return rc;
+ case EINTR:
+ if ((rc= io_wait(ptr, MEM_READ)) == MEMCACHED_SUCCESS)
+ continue;
+ /* fall through */
- rc= io_wait(ptr, MEM_READ);
-
- if (rc == MEMCACHED_SUCCESS)
- continue;
- }
- /* fall trough */
default:
{
memcached_quit_server(ptr, 1);
- return -1;
+ *nread= -1;
+ return rc;
}
}
}
it will return EGAIN if data is not immediatly available.
*/
memcached_quit_server(ptr, 1);
- return -1;
+ *nread= -1;
+ return MEMCACHED_UNKNOWN_READ_FAILURE;
}
}
ptr->io_bytes_sent = 0;
- ptr->read_data_length= data_read;
- ptr->read_buffer_length= data_read;
+ ptr->read_data_length= (size_t) data_read;
+ ptr->read_buffer_length= (size_t) data_read;
ptr->read_ptr= ptr->read_buffer;
}
}
}
- return (size_t)(buffer_ptr - (char*)buffer);
+ ptr->server_failure_counter= 0;
+ *nread = (ssize_t)(buffer_ptr - (char*)buffer);
+ return MEMCACHED_SUCCESS;
}
ssize_t memcached_io_write(memcached_server_st *ptr,
return -1;
/* If io_flush calls memcached_purge, sent_length may be 0 */
- if (sent_length != 0)
- WATCHPOINT_ASSERT(sent_length == buffer_end);
+ unlikely (sent_length != 0)
+ {
+ WATCHPOINT_ASSERT(sent_length == (ssize_t)buffer_end);
+ }
}
}
return -1;
}
- return original_length;
+ return (ssize_t) original_length;
}
memcached_return memcached_io_close(memcached_server_st *ptr)
{
r= shutdown(ptr->fd, SHUT_RDWR);
-#ifdef HAVE_DEBUG
+#ifdef DEBUG
if (r && errno != ENOTCONN)
{
WATCHPOINT_NUMBER(ptr->fd);
}
r= close(ptr->fd);
-#ifdef HAVE_DEBUG
+#ifdef DEBUG
if (r != 0)
WATCHPOINT_ERRNO(errno);
#endif
return MEMCACHED_SUCCESS;
}
+memcached_server_st *memcached_io_get_readable_server(memcached_st *memc)
+{
+#define MAX_SERVERS_TO_POLL 100
+ struct pollfd fds[MAX_SERVERS_TO_POLL];
+ unsigned int host_index= 0;
+
+ for (unsigned int x= 0;
+ x< memc->number_of_hosts && host_index < MAX_SERVERS_TO_POLL;
+ ++x)
+ {
+ if (memc->hosts[x].read_buffer_length > 0) /* I have data in the buffer */
+ return &memc->hosts[x];
+
+ if (memcached_server_response_count(&memc->hosts[x]) > 0)
+ {
+ fds[host_index].events = POLLIN;
+ fds[host_index].revents = 0;
+ fds[host_index].fd = memc->hosts[x].fd;
+ ++host_index;
+ }
+ }
+
+ if (host_index < 2)
+ {
+ /* We have 0 or 1 server with pending events.. */
+ for (unsigned int x= 0; x< memc->number_of_hosts; ++x)
+ if (memcached_server_response_count(&memc->hosts[x]) > 0)
+ return &memc->hosts[x];
+
+ return NULL;
+ }
+
+ int err= poll(fds, host_index, memc->poll_timeout);
+ switch (err) {
+ case -1:
+ memc->cached_errno = errno;
+ /* FALLTHROUGH */
+ case 0:
+ break;
+ default:
+ for (unsigned int x= 0; x < host_index; ++x)
+ if (fds[x].revents & POLLIN)
+ for (unsigned int y= 0; y < memc->number_of_hosts; ++y)
+ if (memc->hosts[y].fd == fds[x].fd)
+ return &memc->hosts[y];
+ }
+
+ return NULL;
+}
+
static ssize_t io_flush(memcached_server_st *ptr,
memcached_return *error)
{
return 0;
/* Looking for memory overflows */
-#if defined(HAVE_DEBUG)
+#if defined(DEBUG)
if (write_length == MEMCACHED_MAX_BUFFER)
WATCHPOINT_ASSERT(ptr->write_buffer == local_write_ptr);
WATCHPOINT_ASSERT((ptr->write_buffer + MEMCACHED_MAX_BUFFER) >= (local_write_ptr + write_length));
continue;
case EAGAIN:
{
+ /*
+ * We may be blocked on write because the input buffer
+ * is full. Let's check if we have room in our input
+ * buffer for more data and retry the write before
+ * waiting..
+ */
+ if (repack_input_buffer(ptr) ||
+ process_input_buffer(ptr))
+ continue;
+
memcached_return rc;
rc= io_wait(ptr, MEM_WRITE);
}
}
- if (ptr->type == MEMCACHED_CONNECTION_UDP && sent_length != write_length)
+ if (ptr->type == MEMCACHED_CONNECTION_UDP &&
+ (size_t)sent_length != write_length)
{
memcached_quit_server(ptr, 1);
return -1;
}
- ptr->io_bytes_sent += sent_length;
+ ptr->io_bytes_sent += (uint32_t) sent_length;
local_write_ptr+= sent_length;
- write_length-= sent_length;
- return_length+= sent_length;
+ write_length-= (uint32_t) sent_length;
+ return_length+= (uint32_t) sent_length;
}
WATCHPOINT_ASSERT(write_length == 0);
else
ptr->write_buffer_offset= 0;
- return return_length;
+ return (ssize_t) return_length;
}
-/*
+/*
Eventually we will just kill off the server with the problem.
*/
void memcached_io_reset(memcached_server_st *ptr)
/**
* Read a given number of bytes from the server and place it into a specific
- * buffer. Reset the IO channel on this server if an error occurs.
+ * buffer. Reset the IO channel on this server if an error occurs.
*/
memcached_return memcached_safe_read(memcached_server_st *ptr,
void *dta,
while (offset < size)
{
- ssize_t nread= memcached_io_read(ptr, data + offset, size - offset);
- if (nread <= 0)
- {
- memcached_io_reset(ptr);
- return MEMCACHED_UNKNOWN_READ_FAILURE;
- }
- offset+= nread;
+ ssize_t nread;
+ memcached_return rc= memcached_io_read(ptr, data + offset, size - offset,
+ &nread);
+ if (rc != MEMCACHED_SUCCESS)
+ return rc;
+
+ offset+= (size_t) nread;
}
return MEMCACHED_SUCCESS;
size_t size)
{
bool line_complete= false;
- int total_nr= 0;
+ size_t total_nr= 0;
while (!line_complete)
{
* buffer. Call the standard read function to avoid duplicating
* the logic.
*/
- if (memcached_io_read(ptr, buffer_ptr, 1) != 1)
- return MEMCACHED_UNKNOWN_READ_FAILURE;
+ ssize_t nread;
+ memcached_return rc= memcached_io_read(ptr, buffer_ptr, 1, &nread);
+ if (rc != MEMCACHED_SUCCESS)
+ return rc;
if (*buffer_ptr == '\n')
line_complete= true;
{
struct udp_datagram_header_st *header= (struct udp_datagram_header_st *)ptr->write_buffer;
uint16_t cur_req= get_udp_datagram_request_id(header);
- uint16_t msg_num= get_msg_num_from_request_id(cur_req);
- uint16_t thread_id= get_thread_id_from_request_id(cur_req);
-
+ int msg_num= get_msg_num_from_request_id(cur_req);
+ int thread_id= get_thread_id_from_request_id(cur_req);
+
if (((++msg_num) & UDP_REQUEST_ID_THREAD_MASK) != 0)
msg_num= 0;
- header->request_id= htons(thread_id | msg_num);
+ header->request_id= htons((uint16_t) (thread_id | msg_num));
}
memcached_return memcached_io_init_udp_header(memcached_server_st *ptr, uint16_t thread_id)
return MEMCACHED_FAILURE;
struct udp_datagram_header_st *header= (struct udp_datagram_header_st *)ptr->write_buffer;
- header->request_id= htons(generate_udp_request_thread_id(thread_id));
+ header->request_id= htons((uint16_t) (generate_udp_request_thread_id(thread_id)));
header->num_datagrams= htons(1);
header->sequence_number= htons(0);