guacamole-spice-protocol/src/libguac/instruction.c

443 lines
15 KiB
C
Raw Normal View History

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is libguac.
*
* The Initial Developer of the Original Code is
* Michael Jumper.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "error.h"
#include "instruction.h"
#include "protocol.h"
#include "socket.h"
#include "unicode.h"
guac_instruction* guac_instruction_alloc() {
/* Allocate space for instruction */
guac_instruction* instruction = malloc(sizeof(guac_instruction));
if (instruction == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Insufficient memory to allocate instruction";
return NULL;
}
/* Initialize state */
instruction->state = GUAC_INSTRUCTION_PARSE_LENGTH;
return instruction;
}
2013-10-02 03:23:20 +00:00
int guac_instruction_append(guac_instruction* instr,
void* buffer, int length) {
2013-10-02 03:23:20 +00:00
char* char_buffer = (char*) buffer;
int bytes_parsed = 0;
2013-10-02 03:23:20 +00:00
/* Do not exceed maximum number of elements */
if (instr->__elementc == GUAC_INSTRUCTION_MAX_ELEMENTS
&& instr->state != GUAC_INSTRUCTION_PARSE_COMPLETE) {
instr->state = GUAC_INSTRUCTION_PARSE_ERROR;
return 0;
}
/* Parse element length */
2013-10-02 03:23:20 +00:00
if (instr->state == GUAC_INSTRUCTION_PARSE_LENGTH) {
int parsed_length = 0;
while (bytes_parsed < length) {
/* Pull next character */
char c = *(char_buffer++);
bytes_parsed++;
/* If digit, add to length */
if (c >= '0' && c <= '9')
parsed_length = parsed_length*10 + c - '0';
/* If period, switch to parsing content */
else if (c == '.') {
2013-10-02 03:57:54 +00:00
instr->__element_length = parsed_length;
2013-10-02 03:23:20 +00:00
instr->state = GUAC_INSTRUCTION_PARSE_CONTENT;
break;
}
/* If not digit, parse error */
else {
instr->state = GUAC_INSTRUCTION_PARSE_ERROR;
return 0;
}
}
/* If too long, parse error */
if (parsed_length > GUAC_INSTRUCTION_MAX_LENGTH) {
instr->state = GUAC_INSTRUCTION_PARSE_ERROR;
return 0;
}
2013-10-02 03:57:54 +00:00
} /* end parse length */
/* Parse element content */
2013-10-02 03:23:20 +00:00
if (instr->state == GUAC_INSTRUCTION_PARSE_CONTENT) {
2013-10-02 03:57:54 +00:00
/* If enough data given, finish element */
if (length - bytes_parsed > instr->__element_length) {
/* Pull terminator */
char terminator = char_buffer[instr->__element_length];
/* Store reference to string within elementv */
instr->__elementv[instr->__elementc++] = char_buffer;
char_buffer[instr->__element_length] = '\0';
bytes_parsed += instr->__element_length+1;
/* If semicolon, store end-of-instruction */
if (terminator == ';') {
instr->state = GUAC_INSTRUCTION_PARSE_COMPLETE;
instr->opcode = instr->__elementv[0];
instr->argv = &(instr->__elementv[1]);
instr->argc = instr->__elementc - 1;
}
/* If comma, move on to next element */
else if (terminator == ',')
instr->state = GUAC_INSTRUCTION_PARSE_LENGTH;
/* Otherwise, parse error */
else {
instr->state = GUAC_INSTRUCTION_PARSE_ERROR;
return 0;
}
}
} /* end parse content */
return bytes_parsed;
}
int __guac_fill_instructionbuf(guac_socket* socket) {
int retval;
/* Attempt to fill buffer */
retval = guac_socket_read(
socket,
socket->__instructionbuf + socket->__instructionbuf_used_length,
socket->__instructionbuf_size - socket->__instructionbuf_used_length
);
/* Set guac_error if recv() unsuccessful */
if (retval < 0) {
guac_error = GUAC_STATUS_SEE_ERRNO;
guac_error_message = "Error filling instruction buffer";
return retval;
}
socket->__instructionbuf_used_length += retval;
/* Expand buffer if necessary */
if (socket->__instructionbuf_used_length >
socket->__instructionbuf_size / 2) {
socket->__instructionbuf_size *= 2;
socket->__instructionbuf = realloc(socket->__instructionbuf,
socket->__instructionbuf_size);
}
return retval;
}
/* Returns new instruction if one exists, or NULL if no more instructions. */
guac_instruction* guac_instruction_read(guac_socket* socket,
int usec_timeout) {
int retval;
/* Loop until a instruction is read */
for (;;) {
/* Length of element, in Unicode characters */
int element_length = 0;
/* Length of element, in bytes */
int element_byte_length = 0;
/* Current position within the element, in Unicode characters */
int current_unicode_length = 0;
/* Position within buffer */
int i = socket->__instructionbuf_parse_start;
/* Parse instruction in buffer */
while (i < socket->__instructionbuf_used_length) {
/* Read character from buffer */
char c = socket->__instructionbuf[i++];
/* If digit, calculate element length */
if (c >= '0' && c <= '9')
element_length = element_length * 10 + c - '0';
/* Otherwise, if end of length */
else if (c == '.') {
/* Calculate element byte length by walking buffer */
while (i + element_byte_length <
socket->__instructionbuf_used_length
&& current_unicode_length < element_length) {
/* Get next byte */
c = socket->__instructionbuf[i + element_byte_length];
/* Update byte and character lengths */
element_byte_length += guac_utf8_charsize((unsigned) c);
current_unicode_length++;
}
/* Verify element is fully read */
if (current_unicode_length == element_length) {
/* Get element value */
char* elementv = &(socket->__instructionbuf[i]);
/* Get terminator, set null terminator of elementv */
char terminator = elementv[element_byte_length];
elementv[element_byte_length] = '\0';
/* Move to char after terminator of element */
i += element_byte_length+1;
/* Reset element length */
element_length =
element_byte_length =
current_unicode_length = 0;
/* As element has been read successfully, update
* parse start */
socket->__instructionbuf_parse_start = i;
/* Save element */
socket->__instructionbuf_elementv[socket->__instructionbuf_elementc++] = elementv;
/* Finish parse if terminator is a semicolon */
if (terminator == ';') {
guac_instruction* parsed_instruction;
int j;
/* Allocate instruction */
parsed_instruction = malloc(sizeof(guac_instruction));
if (parsed_instruction == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for parsed instruction";
return NULL;
}
/* Init parsed instruction */
parsed_instruction->argc = socket->__instructionbuf_elementc - 1;
parsed_instruction->argv = malloc(sizeof(char*) * parsed_instruction->argc);
/* Fail if memory could not be alloc'd for argv */
if (parsed_instruction->argv == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for arguments of parsed instruction";
free(parsed_instruction);
return NULL;
}
/* Set opcode */
parsed_instruction->opcode = strdup(socket->__instructionbuf_elementv[0]);
/* Fail if memory could not be alloc'd for opcode */
if (parsed_instruction->opcode == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for opcode of parsed instruction";
free(parsed_instruction->argv);
free(parsed_instruction);
return NULL;
}
/* Copy element values to parsed instruction */
for (j=0; j<parsed_instruction->argc; j++) {
parsed_instruction->argv[j] = strdup(socket->__instructionbuf_elementv[j+1]);
/* Free memory and fail if out of mem */
if (parsed_instruction->argv[j] == NULL) {
guac_error = GUAC_STATUS_NO_MEMORY;
guac_error_message = "Could not allocate memory for single argument of parsed instruction";
/* Free all alloc'd argv values */
while (--j >= 0)
free(parsed_instruction->argv[j]);
free(parsed_instruction->opcode);
free(parsed_instruction->argv);
free(parsed_instruction);
return NULL;
}
}
/* Reset buffer */
memmove(socket->__instructionbuf, socket->__instructionbuf + i, socket->__instructionbuf_used_length - i);
socket->__instructionbuf_used_length -= i;
socket->__instructionbuf_parse_start = 0;
socket->__instructionbuf_elementc = 0;
/* Done */
return parsed_instruction;
} /* end if terminator */
/* Error if expected comma is not present */
else if (terminator != ',') {
guac_error = GUAC_STATUS_BAD_ARGUMENT;
guac_error_message = "Element terminator of instruction was not ';' nor ','";
return NULL;
}
} /* end if element fully read */
/* Otherwise, read more data */
else
break;
}
/* Error if length is non-numeric or does not end in a period */
else {
guac_error = GUAC_STATUS_BAD_ARGUMENT;
guac_error_message = "Non-numeric character in element length";
return NULL;
}
}
/* No instruction yet? Get more data ... */
retval = guac_socket_select(socket, usec_timeout);
if (retval <= 0)
return NULL;
/* If more data is available, fill into buffer */
retval = __guac_fill_instructionbuf(socket);
/* Error, guac_error already set */
if (retval < 0)
return NULL;
/* EOF */
if (retval == 0) {
guac_error = GUAC_STATUS_NO_INPUT;
guac_error_message = "End of stream reached while reading instruction";
return NULL;
}
}
}
guac_instruction* guac_instruction_expect(guac_socket* socket, int usec_timeout,
const char* opcode) {
guac_instruction* instruction;
/* Wait for data until timeout */
if (guac_instruction_waiting(socket, usec_timeout) <= 0)
return NULL;
/* Read available instruction */
instruction = guac_instruction_read(socket, usec_timeout);
if (instruction == NULL)
return NULL;
/* Validate instruction */
if (strcmp(instruction->opcode, opcode) != 0) {
guac_error = GUAC_STATUS_BAD_STATE;
guac_error_message = "Instruction read did not have expected opcode";
guac_instruction_free(instruction);
return NULL;
}
/* Return instruction if valid */
return instruction;
}
void guac_instruction_free(guac_instruction* instruction) {
int argc = instruction->argc;
/* Free opcode */
free(instruction->opcode);
/* Free argv if set (may be NULL of argc is 0) */
if (instruction->argv) {
/* All argument values */
while (argc > 0)
free(instruction->argv[--argc]);
/* Free actual array */
free(instruction->argv);
}
/* Free instruction */
free(instruction);
}
int guac_instruction_waiting(guac_socket* socket, int usec_timeout) {
if (socket->__instructionbuf_used_length > 0)
return 1;
return guac_socket_select(socket, usec_timeout);
}