guacamole-spice-protocol/src/libguac/socket.c
2014-01-01 14:52:01 -08:00

422 lines
12 KiB
C

/*
* Copyright (C) 2013 Glyptodon LLC
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "config.h"
#include "error.h"
#include "protocol.h"
#include "socket.h"
#include "timestamp.h"
#include <fcntl.h>
#include <inttypes.h>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <time.h>
#include <unistd.h>
#ifdef __MINGW32__
#include <winsock2.h>
#else
#include <sys/select.h>
#endif
char __guac_socket_BASE64_CHARACTERS[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', '+', '/'
};
static void* __guac_socket_keep_alive_thread(void* data) {
/* Calculate sleep interval */
struct timespec interval;
interval.tv_sec = GUAC_SOCKET_KEEP_ALIVE_INTERVAL / 1000;
interval.tv_nsec = (GUAC_SOCKET_KEEP_ALIVE_INTERVAL % 1000) * 1000000L;
/* Socket keep-alive loop */
guac_socket* socket = (guac_socket*) data;
while (socket->state == GUAC_SOCKET_OPEN) {
/* Send NOP keep-alive if it's been a while since the last output */
guac_timestamp timestamp = guac_timestamp_current();
if (timestamp - socket->last_write_timestamp >
GUAC_SOCKET_KEEP_ALIVE_INTERVAL) {
/* Send NOP */
if (guac_protocol_send_nop(socket)
|| guac_socket_flush(socket))
break;
}
/* Sleep until next keep-alive check */
nanosleep(&interval, NULL);
}
return NULL;
}
static ssize_t __guac_socket_write(guac_socket* socket,
const void* buf, size_t count) {
/* Update timestamp of last write */
socket->last_write_timestamp = guac_timestamp_current();
/* If handler defined, call it. */
if (socket->write_handler)
return socket->write_handler(socket, buf, count);
/* Otherwise, pretend everything was written. */
return count;
}
ssize_t guac_socket_write(guac_socket* socket,
const void* buf, size_t count) {
const char* buffer = buf;
/* Write until completely written */
while (count > 0) {
/* Attempt to write, return on error */
int written = __guac_socket_write(socket, buffer, count);
if (written == -1)
return 1;
/* Advance buffer as data written */
buffer += written;
count -= written;
}
return 0;
}
ssize_t guac_socket_read(guac_socket* socket, void* buf, size_t count) {
/* If handler defined, call it. */
if (socket->read_handler)
return socket->read_handler(socket, buf, count);
/* Otherwise, pretend nothing was read. */
return 0;
}
int guac_socket_select(guac_socket* socket, int usec_timeout) {
/* Call select handler if defined */
if (socket->select_handler)
return socket->select_handler(socket, usec_timeout);
/* Otherwise, assume ready. */
return 1;
}
guac_socket* guac_socket_alloc() {
pthread_mutexattr_t lock_attributes;
guac_socket* socket = malloc(sizeof(guac_socket));
/* If no memory available, return with error */
if (socket == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for socket";
return NULL;
}
socket->__ready = 0;
socket->__written = 0;
socket->data = NULL;
socket->state = GUAC_SOCKET_OPEN;
/* Init members */
socket->__instructionbuf_unparsed_start = socket->__instructionbuf;
socket->__instructionbuf_unparsed_end = socket->__instructionbuf;
/* Default to unsafe threading */
socket->__threadsafe_instructions = 0;
pthread_mutexattr_init(&lock_attributes);
pthread_mutexattr_setpshared(&lock_attributes, PTHREAD_PROCESS_SHARED);
pthread_mutex_init(&(socket->__instruction_write_lock), &lock_attributes);
pthread_mutex_init(&(socket->__buffer_lock), &lock_attributes);
/* No handlers yet */
socket->read_handler = NULL;
socket->write_handler = NULL;
socket->select_handler = NULL;
socket->free_handler = NULL;
return socket;
}
void guac_socket_require_threadsafe(guac_socket* socket) {
socket->__threadsafe_instructions = 1;
}
void guac_socket_require_keep_alive(guac_socket* socket) {
/* Keep-alive thread requires a threadsafe socket */
guac_socket_require_threadsafe(socket);
/* Start keep-alive thread */
socket->__keep_alive_enabled = 1;
pthread_create(&(socket->__keep_alive_thread), NULL,
__guac_socket_keep_alive_thread, (void*) socket);
}
void guac_socket_instruction_begin(guac_socket* socket) {
/* Lock writes if threadsafety enabled */
if (socket->__threadsafe_instructions)
pthread_mutex_lock(&(socket->__instruction_write_lock));
}
void guac_socket_instruction_end(guac_socket* socket) {
/* Unlock writes if threadsafety enabled */
if (socket->__threadsafe_instructions)
pthread_mutex_unlock(&(socket->__instruction_write_lock));
}
void guac_socket_update_buffer_begin(guac_socket* socket) {
/* Lock if threadsafety enabled */
if (socket->__threadsafe_instructions)
pthread_mutex_lock(&(socket->__buffer_lock));
}
void guac_socket_update_buffer_end(guac_socket* socket) {
/* Unlock if threadsafety enabled */
if (socket->__threadsafe_instructions)
pthread_mutex_unlock(&(socket->__buffer_lock));
}
void guac_socket_free(guac_socket* socket) {
/* Call free handler if defined */
if (socket->free_handler)
socket->free_handler(socket);
guac_socket_flush(socket);
/* Mark as closed */
socket->state = GUAC_SOCKET_CLOSED;
/* Wait for keep-alive, if enabled */
if (socket->__keep_alive_enabled)
pthread_join(socket->__keep_alive_thread, NULL);
pthread_mutex_destroy(&(socket->__instruction_write_lock));
free(socket);
}
ssize_t guac_socket_write_int(guac_socket* socket, int64_t i) {
char buffer[128];
snprintf(buffer, sizeof(buffer), "%"PRIi64, i);
return guac_socket_write_string(socket, buffer);
}
ssize_t guac_socket_write_string(guac_socket* socket, const char* str) {
char* __out_buf = socket->__out_buf;
guac_socket_update_buffer_begin(socket);
for (; *str != '\0'; str++) {
__out_buf[socket->__written++] = *str;
/* Flush when necessary, return on error. Note that we must flush within 4 bytes of boundary because
* __guac_socket_write_base64_triplet ALWAYS writes four bytes, and would otherwise potentially overflow
* the buffer. */
if (socket->__written > GUAC_SOCKET_OUTPUT_BUFFER_SIZE - 4) {
if (guac_socket_write(socket, __out_buf, socket->__written)) {
guac_socket_update_buffer_end(socket);
return 1;
}
socket->__written = 0;
}
}
guac_socket_update_buffer_end(socket);
return 0;
}
ssize_t __guac_socket_write_base64_triplet(guac_socket* socket, int a, int b, int c) {
char* __out_buf = socket->__out_buf;
/* Byte 1 */
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[(a & 0xFC) >> 2]; /* [AAAAAA]AABBBB BBBBCC CCCCCC */
if (b >= 0) {
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[((a & 0x03) << 4) | ((b & 0xF0) >> 4)]; /* AAAAAA[AABBBB]BBBBCC CCCCCC */
if (c >= 0) {
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[((b & 0x0F) << 2) | ((c & 0xC0) >> 6)]; /* AAAAAA AABBBB[BBBBCC]CCCCCC */
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[c & 0x3F]; /* AAAAAA AABBBB BBBBCC[CCCCCC] */
}
else {
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[((b & 0x0F) << 2)]; /* AAAAAA AABBBB[BBBB--]------ */
__out_buf[socket->__written++] = '='; /* AAAAAA AABBBB BBBB--[------] */
}
}
else {
__out_buf[socket->__written++] = __guac_socket_BASE64_CHARACTERS[((a & 0x03) << 4)]; /* AAAAAA[AA----]------ ------ */
__out_buf[socket->__written++] = '='; /* AAAAAA AA----[------]------ */
__out_buf[socket->__written++] = '='; /* AAAAAA AA---- ------[------] */
}
/* At this point, 4 bytes have been socket->__written */
/* Flush when necessary, return on error */
if (socket->__written > GUAC_SOCKET_OUTPUT_BUFFER_SIZE - 4) {
if (guac_socket_write(socket, __out_buf, socket->__written))
return -1;
socket->__written = 0;
}
if (b < 0)
return 1;
if (c < 0)
return 2;
return 3;
}
ssize_t __guac_socket_write_base64_byte(guac_socket* socket, int buf) {
int* __ready_buf = socket->__ready_buf;
int retval;
__ready_buf[socket->__ready++] = buf;
/* Flush triplet */
if (socket->__ready == 3) {
retval = __guac_socket_write_base64_triplet(socket, __ready_buf[0], __ready_buf[1], __ready_buf[2]);
if (retval < 0)
return retval;
socket->__ready = 0;
}
return 1;
}
ssize_t guac_socket_write_base64(guac_socket* socket, const void* buf, size_t count) {
int retval;
const unsigned char* char_buf = (const unsigned char*) buf;
const unsigned char* end = char_buf + count;
guac_socket_update_buffer_begin(socket);
while (char_buf < end) {
retval = __guac_socket_write_base64_byte(socket, *(char_buf++));
if (retval < 0) {
guac_socket_update_buffer_end(socket);
return retval;
}
}
guac_socket_update_buffer_end(socket);
return 0;
}
ssize_t guac_socket_flush(guac_socket* socket) {
/* Flush remaining bytes in buffer */
guac_socket_update_buffer_begin(socket);
if (socket->__written > 0) {
if (guac_socket_write(socket, socket->__out_buf, socket->__written)) {
guac_socket_update_buffer_end(socket);
return 1;
}
socket->__written = 0;
}
guac_socket_update_buffer_end(socket);
return 0;
}
ssize_t guac_socket_flush_base64(guac_socket* socket) {
int retval;
/* Flush triplet to output buffer */
guac_socket_update_buffer_begin(socket);
while (socket->__ready > 0) {
retval = __guac_socket_write_base64_byte(socket, -1);
if (retval < 0) {
guac_socket_update_buffer_end(socket);
return retval;
}
}
guac_socket_update_buffer_end(socket);
return 0;
}