guacamole-spice-protocol/src/guaclog/interpret.c

153 lines
4.5 KiB
C

/*
* 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 "config.h"
#include "instructions.h"
#include "log.h"
#include "state.h"
#include <guacamole/client.h>
#include <guacamole/error.h>
#include <guacamole/parser.h>
#include <guacamole/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
/**
* Reads and handles all Guacamole instructions from the given guac_socket
* until end-of-stream is reached.
*
* @param state
* The current state of the Guacamole input log interpreter.
*
* @param path
* The name of the file being parsed (for logging purposes). This file
* must already be open and available through the given socket.
*
* @param socket
* The guac_socket through which instructions should be read.
*
* @return
* Zero on success, non-zero if parsing of Guacamole protocol data through
* the given socket fails.
*/
static int guaclog_read_instructions(guaclog_state* state,
const char* path, guac_socket* socket) {
/* Obtain Guacamole protocol parser */
guac_parser* parser = guac_parser_alloc();
if (parser == NULL)
return 1;
/* Continuously read and handle all instructions */
while (!guac_parser_read(parser, socket, -1)) {
guaclog_handle_instruction(state, parser->opcode,
parser->argc, parser->argv);
}
/* Fail on read/parse error */
if (guac_error != GUAC_STATUS_CLOSED) {
guaclog_log(GUAC_LOG_ERROR, "%s: %s",
path, guac_status_string(guac_error));
guac_parser_free(parser);
return 1;
}
/* Parse complete */
guac_parser_free(parser);
return 0;
}
int guaclog_interpret(const char* path, const char* out_path, bool force) {
/* Open input file */
int fd = open(path, O_RDONLY);
if (fd < 0) {
guaclog_log(GUAC_LOG_ERROR, "%s: %s", path, strerror(errno));
return 1;
}
/* Lock entire input file for reading by the current process */
struct flock file_lock = {
.l_type = F_RDLCK,
.l_whence = SEEK_SET,
.l_start = 0,
.l_len = 0,
.l_pid = getpid()
};
/* Abort if file cannot be locked for reading */
if (!force && fcntl(fd, F_SETLK, &file_lock) == -1) {
/* Warn if lock cannot be acquired */
if (errno == EACCES || errno == EAGAIN)
guaclog_log(GUAC_LOG_WARNING, "Refusing to interpret log of "
"in-progress session \"%s\" (specify the -f option to "
"override this behavior).", path);
/* Log an error if locking fails in an unexpected way */
else
guaclog_log(GUAC_LOG_ERROR, "Cannot lock \"%s\" for reading: %s",
path, strerror(errno));
close(fd);
return 1;
}
/* Allocate input state for interpreting process */
guaclog_state* state = guaclog_state_alloc(out_path);
if (state == NULL) {
close(fd);
return 1;
}
/* Obtain guac_socket wrapping file descriptor */
guac_socket* socket = guac_socket_open(fd);
if (socket == NULL) {
guaclog_log(GUAC_LOG_ERROR, "%s: %s", path,
guac_status_string(guac_error));
close(fd);
guaclog_state_free(state);
return 1;
}
guaclog_log(GUAC_LOG_INFO, "Writing input events from \"%s\" "
"to \"%s\" ...", path, out_path);
/* Attempt to read all instructions in the file */
if (guaclog_read_instructions(state, path, socket)) {
guac_socket_free(socket);
guaclog_state_free(state);
return 1;
}
/* Close input and finish interpreting process */
guac_socket_free(socket);
return guaclog_state_free(state);
}