GUACAMOLE-118: Use poll() when waiting for data from RDP. Reformat for sake of readability/verification.

This commit is contained in:
Michael Jumper 2016-11-11 13:45:01 -08:00
parent 2421fc2f11
commit c12e26404a
2 changed files with 56 additions and 51 deletions

View File

@ -38,12 +38,12 @@
/**
* The amount of time to wait for a new message from the RDP server when
* beginning a new frame. This value must be kept reasonably small such that
* a slow RDP server will not prevent external events from being handled (such
* as the stop signal from guac_client_stop()), but large enough that the
* message handling loop does not eat up CPU spinning.
* beginning a new frame, in milliseconds. This value must be kept reasonably
* small such that a slow RDP server will not prevent external events from
* being handled (such as the stop signal from guac_client_stop()), but large
* enough that the message handling loop does not eat up CPU spinning.
*/
#define GUAC_RDP_FRAME_START_TIMEOUT 250000
#define GUAC_RDP_FRAME_START_TIMEOUT 250
/**
* The native resolution of most RDP connections. As Windows and other systems
@ -89,6 +89,12 @@
*/
#define GUAC_RDP_AUDIO_BPS 16
/**
* The maximum number of file descriptors which can be associated with an RDP
* connection.
*/
#define GUAC_RDP_MAX_FILE_DESCRIPTORS 32
/**
* Handler which frees all data associated with the guac_client.
*/

View File

@ -97,10 +97,10 @@
#endif
#include <errno.h>
#include <poll.h>
#include <pthread.h>
#include <stdlib.h>
#include <string.h>
#include <sys/select.h>
#include <sys/time.h>
#include <time.h>
@ -545,20 +545,20 @@ static void rdp_freerdp_context_free(freerdp* instance, rdpContext* context) {
}
/**
* Waits for messages from the RDP server for the given number of microseconds.
* Waits for messages from the RDP server for the given number of milliseconds.
*
* @param client
* The client associated with the current RDP session.
*
* @param timeout_usecs
* The maximum amount of time to wait, in microseconds.
* @param timeout_msecs
* The maximum amount of time to wait, in milliseconds.
*
* @return
* A positive value if messages are ready, zero if the specified timeout
* period elapsed, or a negative value if an error occurs.
*/
static int rdp_guac_client_wait_for_messages(guac_client* client,
int timeout_usecs) {
int timeout_msecs) {
guac_rdp_client* rdp_client = (guac_rdp_client*) client->data;
freerdp* rdp_inst = rdp_client->rdp_inst;
@ -566,58 +566,56 @@ static int rdp_guac_client_wait_for_messages(guac_client* client,
int result;
int index;
int max_fd, fd;
void* read_fds[32];
void* write_fds[32];
/* List of all file descriptors which we may read data from */
void* read_fds[GUAC_RDP_MAX_FILE_DESCRIPTORS];
int read_count = 0;
/* List of all file descriptors which data may be written to. These will
* ultimately be ignored, but FreeRDP requires that both read and write
* file descriptors be retrieved simultaneously. */
void* write_fds[GUAC_RDP_MAX_FILE_DESCRIPTORS];
int write_count = 0;
fd_set rfds, wfds;
struct timeval timeout = {
.tv_sec = 0,
.tv_usec = timeout_usecs
};
struct pollfd fds[GUAC_RDP_MAX_FILE_DESCRIPTORS];
/* Get RDP fds */
if (!freerdp_get_fds(rdp_inst, read_fds, &read_count, write_fds, &write_count)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "Unable to read RDP file descriptors.");
/* Get RDP file descriptors */
if (!freerdp_get_fds(rdp_inst, read_fds, &read_count,
write_fds, &write_count)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"Unable to read RDP file descriptors.");
return -1;
}
/* Get channel fds */
if (!freerdp_channels_get_fds(channels, rdp_inst, read_fds, &read_count, write_fds,
&write_count)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "Unable to read RDP channel file descriptors.");
/* Get RDP channel file descriptors */
if (!freerdp_channels_get_fds(channels, rdp_inst, read_fds, &read_count,
write_fds, &write_count)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"Unable to read RDP channel file descriptors.");
return -1;
}
/* Construct read fd_set */
max_fd = 0;
FD_ZERO(&rfds);
for (index = 0; index < read_count; index++) {
fd = (int)(long) (read_fds[index]);
if (fd > max_fd)
max_fd = fd;
FD_SET(fd, &rfds);
}
/* Construct write fd_set */
FD_ZERO(&wfds);
for (index = 0; index < write_count; index++) {
fd = (int)(long) (write_fds[index]);
if (fd > max_fd)
max_fd = fd;
FD_SET(fd, &wfds);
}
/* If no file descriptors, error */
if (max_fd == 0) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "No file descriptors associated with RDP connection.");
if (read_count == 0) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"No file descriptors associated with RDP connection.");
return -1;
}
/* Wait for all RDP file descriptors */
result = select(max_fd + 1, &rfds, &wfds, NULL, &timeout);
/* Populate poll() array of read file descriptors */
for (index = 0; index < read_count; index++) {
struct pollfd* current = &fds[index];
/* Init poll() array element with RDP file descriptor */
current->fd = (int)(long) (read_fds[index]);
current->events = POLLIN;
current->revents = 0;
}
/* Wait until data can be read from RDP file descriptors */
result = poll(fds, read_count, timeout_msecs);
if (result < 0) {
/* If error ignorable, pretend timout occurred */
@ -628,7 +626,8 @@ static int rdp_guac_client_wait_for_messages(guac_client* client,
return 0;
/* Otherwise, return as error */
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "Error waiting for file descriptor.");
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"Error waiting for file descriptor.");
return -1;
}
@ -823,12 +822,12 @@ static int guac_rdp_handle_connection(guac_client* client) {
/* Increase the duration of this frame if client is lagging */
if (required_wait > GUAC_RDP_FRAME_TIMEOUT)
wait_result = rdp_guac_client_wait_for_messages(client,
required_wait*1000);
required_wait);
/* Wait again if frame remaining */
else if (frame_remaining > 0)
wait_result = rdp_guac_client_wait_for_messages(client,
GUAC_RDP_FRAME_TIMEOUT*1000);
GUAC_RDP_FRAME_TIMEOUT);
else
break;