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Posted to commits@guacamole.apache.org by vn...@apache.org on 2017/08/13 18:26:46 UTC
[8/9] incubator-guacamole-server git commit: GUACAMOLE-325: Add
Winsock-specific guac_socket implementation.
GUACAMOLE-325: Add Winsock-specific guac_socket implementation.
Project: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/commit/d3c5a8a0
Tree: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/tree/d3c5a8a0
Diff: http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/diff/d3c5a8a0
Branch: refs/heads/master
Commit: d3c5a8a050e5b0a9594574207d55c77af64e4947
Parents: eb73563
Author: Michael Jumper <mj...@apache.org>
Authored: Mon Jun 12 14:34:07 2017 -0700
Committer: Michael Jumper <mj...@apache.org>
Committed: Wed Jul 5 20:55:03 2017 -0700
----------------------------------------------------------------------
src/libguac/Makefile.am | 6 +
src/libguac/guacamole/socket-wsa.h | 51 ++++
src/libguac/socket-wsa.c | 448 ++++++++++++++++++++++++++++++++
3 files changed, 505 insertions(+)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/blob/d3c5a8a0/src/libguac/Makefile.am
----------------------------------------------------------------------
diff --git a/src/libguac/Makefile.am b/src/libguac/Makefile.am
index 4a62f97..0d30f63 100644
--- a/src/libguac/Makefile.am
+++ b/src/libguac/Makefile.am
@@ -108,6 +108,12 @@ libguac_la_SOURCES += socket-ssl.c
libguacinc_HEADERS += guacamole/socket-ssl.h
endif
+# Winsock support
+if ENABLE_WINSOCK
+libguac_la_SOURCES += socket-wsa.c
+libguacinc_HEADERS += guacamole/socket-wsa.h
+endif
+
libguac_la_CFLAGS = \
-Werror -Wall -pedantic -Iguacamole
http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/blob/d3c5a8a0/src/libguac/guacamole/socket-wsa.h
----------------------------------------------------------------------
diff --git a/src/libguac/guacamole/socket-wsa.h b/src/libguac/guacamole/socket-wsa.h
new file mode 100644
index 0000000..9eb1d52
--- /dev/null
+++ b/src/libguac/guacamole/socket-wsa.h
@@ -0,0 +1,51 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef GUAC_SOCKET_WSA_H
+#define GUAC_SOCKET_WSA_H
+
+/**
+ * Provides an implementation of guac_socket specific to the Windows Socket API
+ * (aka WSA or "winsock"). This header will only be available if libguac was
+ * built with WSA support.
+ *
+ * @file socket-wsa.h
+ */
+
+#include "socket-types.h"
+
+#include <winsock2.h>
+
+/**
+ * Creates a new guac_socket which will use the Windows Socket API (aka WSA or
+ * "winsock") for all communication. Freeing this guac_socket will
+ * automatically close the associated SOCKET handle.
+ *
+ * @param sock
+ * The WSA SOCKET handle to use for the connection underlying the created
+ * guac_socket.
+ *
+ * @return
+ * A newly-allocated guac_socket which will transparently use the Windows
+ * Socket API for all communication.
+ */
+guac_socket* guac_socket_open_wsa(SOCKET sock);
+
+#endif
+
http://git-wip-us.apache.org/repos/asf/incubator-guacamole-server/blob/d3c5a8a0/src/libguac/socket-wsa.c
----------------------------------------------------------------------
diff --git a/src/libguac/socket-wsa.c b/src/libguac/socket-wsa.c
new file mode 100644
index 0000000..1b59176
--- /dev/null
+++ b/src/libguac/socket-wsa.c
@@ -0,0 +1,448 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "error.h"
+#include "socket.h"
+
+#include <pthread.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <winsock2.h>
+
+/**
+ * Data associated with an open socket which uses the Windows Socket API.
+ */
+typedef struct guac_socket_wsa_data {
+
+ /**
+ * The associated Windows socket handle.
+ */
+ SOCKET sock;
+
+ /**
+ * The number of bytes currently in the main write buffer.
+ */
+ int written;
+
+ /**
+ * The main write buffer. Bytes written go here before being flushed
+ * to the open socket.
+ */
+ char out_buf[GUAC_SOCKET_OUTPUT_BUFFER_SIZE];
+
+ /**
+ * Lock which is acquired when an instruction is being written, and
+ * released when the instruction is finished being written.
+ */
+ pthread_mutex_t socket_lock;
+
+ /**
+ * Lock which protects access to the internal buffer of this socket,
+ * guaranteeing atomicity of writes and flushes.
+ */
+ pthread_mutex_t buffer_lock;
+
+} guac_socket_wsa_data;
+
+/**
+ * Writes the entire contents of the given buffer to the SOCKET handle
+ * associated with the given socket, retrying as necessary until the whole
+ * buffer is written, and aborting if an error occurs.
+ *
+ * @param socket
+ * The guac_socket associated with the SOCKET handle to which the given
+ * buffer should be written.
+ *
+ * @param buf
+ * The buffer of data to write to the given guac_socket.
+ *
+ * @param count
+ * The number of bytes within the given buffer.
+ *
+ * @return
+ * The number of bytes written, which will be exactly the size of the given
+ * buffer, or a negative value if an error occurs.
+ */
+ssize_t guac_socket_wsa_write(guac_socket* socket,
+ const void* buf, size_t count) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+ const char* buffer = buf;
+
+ /* Write until completely written */
+ while (count > 0) {
+
+ int retval = send(data->sock, buffer, count, 0);
+
+ /* Record errors in guac_error */
+ if (retval < 0) {
+ guac_error = GUAC_STATUS_SEE_ERRNO;
+ guac_error_message = "Error writing data to socket";
+ return retval;
+ }
+
+ /* Advance buffer as data retval */
+ buffer += retval;
+ count -= retval;
+
+ }
+
+ return 0;
+
+}
+
+/**
+ * Attempts to read from the underlying SOCKET handle of the given guac_socket,
+ * populating the given buffer.
+ *
+ * @param socket
+ * The guac_socket being read from.
+ *
+ * @param buf
+ * The arbitrary buffer which we must populate with data.
+ *
+ * @param count
+ * The maximum number of bytes to read into the buffer.
+ *
+ * @return
+ * The number of bytes read, or -1 if an error occurs.
+ */
+static ssize_t guac_socket_wsa_read_handler(guac_socket* socket,
+ void* buf, size_t count) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Read from socket */
+ int retval = recv(data->sock, buf, count, 0);
+
+ /* Record errors in guac_error */
+ if (retval < 0) {
+ guac_error = GUAC_STATUS_SEE_ERRNO;
+ guac_error_message = "Error reading data from socket";
+ }
+
+ return retval;
+
+}
+
+/**
+ * Flushes the contents of the output buffer of the given socket immediately,
+ * without first locking access to the output buffer. This function must ONLY
+ * be called if the buffer lock has already been acquired.
+ *
+ * @param socket
+ * The guac_socket to flush.
+ *
+ * @return
+ * Zero if the flush operation was successful, non-zero otherwise.
+ */
+static ssize_t guac_socket_wsa_flush(guac_socket* socket) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Flush remaining bytes in buffer */
+ if (data->written > 0) {
+
+ /* Write ALL bytes in buffer immediately */
+ if (guac_socket_wsa_write(socket, data->out_buf, data->written))
+ return 1;
+
+ data->written = 0;
+ }
+
+ return 0;
+
+}
+
+/**
+ * Flushes the internal buffer of the given guac_socket, writing all data
+ * to the underlying SOCKET handle.
+ *
+ * @param socket
+ * The guac_socket to flush.
+ *
+ * @return
+ * Zero if the flush operation was successful, non-zero otherwise.
+ */
+static ssize_t guac_socket_wsa_flush_handler(guac_socket* socket) {
+
+ int retval;
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Acquire exclusive access to buffer */
+ pthread_mutex_lock(&(data->buffer_lock));
+
+ /* Flush contents of buffer */
+ retval = guac_socket_wsa_flush(socket);
+
+ /* Relinquish exclusive access to buffer */
+ pthread_mutex_unlock(&(data->buffer_lock));
+
+ return retval;
+
+}
+
+/**
+ * Writes the contents of the buffer to the output buffer of the given socket,
+ * flushing the output buffer as necessary, without first locking access to the
+ * output buffer. This function must ONLY be called if the buffer lock has
+ * already been acquired.
+ *
+ * @param socket
+ * The guac_socket to write the given buffer to.
+ *
+ * @param buf
+ * The buffer to write to the given socket.
+ *
+ * @param count
+ * The number of bytes in the given buffer.
+ *
+ * @return
+ * The number of bytes written, or a negative value if an error occurs
+ * during write.
+ */
+static ssize_t guac_socket_wsa_write_buffered(guac_socket* socket,
+ const void* buf, size_t count) {
+
+ size_t original_count = count;
+ const char* current = buf;
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Append to buffer, flush if necessary */
+ while (count > 0) {
+
+ int chunk_size;
+ int remaining = sizeof(data->out_buf) - data->written;
+
+ /* If no space left in buffer, flush and retry */
+ if (remaining == 0) {
+
+ /* Abort if error occurs during flush */
+ if (guac_socket_wsa_flush(socket))
+ return -1;
+
+ /* Retry buffer append */
+ continue;
+
+ }
+
+ /* Calculate size of chunk to be written to buffer */
+ chunk_size = count;
+ if (chunk_size > remaining)
+ chunk_size = remaining;
+
+ /* Update output buffer */
+ memcpy(data->out_buf + data->written, current, chunk_size);
+ data->written += chunk_size;
+
+ /* Update provided buffer */
+ current += chunk_size;
+ count -= chunk_size;
+
+ }
+
+ /* All bytes have been written, possibly some to the internal buffer */
+ return original_count;
+
+}
+
+/**
+ * Appends the provided data to the internal buffer for future writing. The
+ * actual write attempt will occur only upon flush, or when the internal buffer
+ * is full.
+ *
+ * @param socket
+ * The guac_socket being write to.
+ *
+ * @param buf
+ * The arbitrary buffer containing the data to be written.
+ *
+ * @param count
+ * The number of bytes contained within the buffer.
+ *
+ * @return
+ * The number of bytes written, or -1 if an error occurs.
+ */
+static ssize_t guac_socket_wsa_write_handler(guac_socket* socket,
+ const void* buf, size_t count) {
+
+ int retval;
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Acquire exclusive access to buffer */
+ pthread_mutex_lock(&(data->buffer_lock));
+
+ /* Write provided data to buffer */
+ retval = guac_socket_wsa_write_buffered(socket, buf, count);
+
+ /* Relinquish exclusive access to buffer */
+ pthread_mutex_unlock(&(data->buffer_lock));
+
+ return retval;
+
+}
+
+/**
+ * Waits for data on the underlying SOCKET handle of the given socket to
+ * become available such that the next read operation will not block.
+ *
+ * @param socket
+ * The guac_socket to wait for.
+ *
+ * @param usec_timeout
+ * The maximum amount of time to wait for data, in microseconds, or -1 to
+ * potentially wait forever.
+ *
+ * @return
+ * A positive value on success, zero if the timeout elapsed and no data is
+ * available, or a negative value if an error occurs.
+ */
+static int guac_socket_wsa_select_handler(guac_socket* socket,
+ int usec_timeout) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ fd_set sockets;
+ struct timeval timeout;
+ int retval;
+
+ /* Initialize fd_set with single underlying socket handle */
+ FD_ZERO(&sockets);
+ FD_SET(data->sock, &sockets);
+
+ /* No timeout if usec_timeout is negative */
+ if (usec_timeout < 0)
+ retval = select(0, &sockets, NULL, NULL, NULL);
+
+ /* Handle timeout if specified */
+ else {
+ timeout.tv_sec = usec_timeout / 1000000;
+ timeout.tv_usec = usec_timeout % 1000000;
+ retval = select(0, &sockets, NULL, NULL, &timeout);
+ }
+
+ /* Properly set guac_error */
+ if (retval < 0) {
+ guac_error = GUAC_STATUS_SEE_ERRNO;
+ guac_error_message = "Error while waiting for data on socket";
+ }
+
+ if (retval == 0) {
+ guac_error = GUAC_STATUS_TIMEOUT;
+ guac_error_message = "Timeout while waiting for data on socket";
+ }
+
+ return retval;
+
+}
+
+/**
+ * Frees all implementation-specific data associated with the given socket, but
+ * not the socket object itself.
+ *
+ * @param socket
+ * The guac_socket whose associated data should be freed.
+ *
+ * @return
+ * Zero if the data was successfully freed, non-zero otherwise. This
+ * implementation always succeeds, and will always return zero.
+ */
+static int guac_socket_wsa_free_handler(guac_socket* socket) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Destroy locks */
+ pthread_mutex_destroy(&(data->socket_lock));
+ pthread_mutex_destroy(&(data->buffer_lock));
+
+ /* Close socket */
+ closesocket(data->sock);
+
+ free(data);
+ return 0;
+
+}
+
+/**
+ * Acquires exclusive access to the given socket.
+ *
+ * @param socket
+ * The guac_socket to which exclusive access is required.
+ */
+static void guac_socket_wsa_lock_handler(guac_socket* socket) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Acquire exclusive access to socket */
+ pthread_mutex_lock(&(data->socket_lock));
+
+}
+
+/**
+ * Relinquishes exclusive access to the given socket.
+ *
+ * @param socket
+ * The guac_socket to which exclusive access is no longer required.
+ */
+static void guac_socket_wsa_unlock_handler(guac_socket* socket) {
+
+ guac_socket_wsa_data* data = (guac_socket_wsa_data*) socket->data;
+
+ /* Relinquish exclusive access to socket */
+ pthread_mutex_unlock(&(data->socket_lock));
+
+}
+
+guac_socket* guac_socket_open_wsa(SOCKET sock) {
+
+ pthread_mutexattr_t lock_attributes;
+
+ /* Allocate socket and associated data */
+ guac_socket* socket = guac_socket_alloc();
+ guac_socket_wsa_data* data = malloc(sizeof(guac_socket_wsa_data));
+
+ /* Store socket as socket data */
+ data->sock = sock;
+ data->written = 0;
+ socket->data = data;
+
+ pthread_mutexattr_init(&lock_attributes);
+ pthread_mutexattr_setpshared(&lock_attributes, PTHREAD_PROCESS_SHARED);
+
+ /* Init locks */
+ pthread_mutex_init(&(data->socket_lock), &lock_attributes);
+ pthread_mutex_init(&(data->buffer_lock), &lock_attributes);
+
+ /* Set read/write handlers */
+ socket->read_handler = guac_socket_wsa_read_handler;
+ socket->write_handler = guac_socket_wsa_write_handler;
+ socket->select_handler = guac_socket_wsa_select_handler;
+ socket->lock_handler = guac_socket_wsa_lock_handler;
+ socket->unlock_handler = guac_socket_wsa_unlock_handler;
+ socket->flush_handler = guac_socket_wsa_flush_handler;
+ socket->free_handler = guac_socket_wsa_free_handler;
+
+ return socket;
+
+}
+