seamlessrdp/ServerExe/vchannel.c

/* -*- c-basic-offset: 8 -*-
   rdesktop: A Remote Desktop Protocol client.
   Seamless windows - Virtual channel handling

   Copyright (C) Pierre Ossman <ossman@cendio.se> 2006

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <assert.h>
#include <stdio.h>
#include <stdarg.h>
#include <errno.h>

#include <windows.h>
#include <wtsapi32.h>
#include <cchannel.h>

#include "vchannel.h"

#define CHANNELNAME "seamrdp"

static HANDLE g_mutex = NULL;
static HANDLE g_vchannel = NULL;

void
debug(char *format, ...)
{
        va_list argp;
        char buf[256];

        sprintf(buf, "DEBUG1,");

        va_start(argp, format);
        _vsnprintf(buf + sizeof("DEBUG1,") - 1, sizeof(buf) - sizeof("DEBUG1,") + 1, format, argp);
        va_end(argp);

        vchannel_write(buf);
}


int
vchannel_open()
{
        g_vchannel = WTSVirtualChannelOpen(WTS_CURRENT_SERVER_HANDLE,
                                           WTS_CURRENT_SESSION, CHANNELNAME);

        if (g_vchannel == NULL)
                return -1;

        g_mutex = CreateMutex(NULL, FALSE, "Local\\SeamlessChannel");
        if (!g_mutex) {
                WTSVirtualChannelClose(g_vchannel);
                g_vchannel = NULL;
                return -1;
        }

        return 0;
}

void
vchannel_close()
{
        if (g_mutex)
                CloseHandle(g_mutex);

        if (g_vchannel)
                WTSVirtualChannelClose(g_vchannel);

        g_mutex = NULL;
        g_vchannel = NULL;
}

int
vchannel_is_open()
{
        if (g_vchannel == NULL)
                return 0;
        else
                return 1;
}

int
vchannel_read(char *line, size_t length)
{
        static BOOL overflow_mode = FALSE;
        static char buffer[VCHANNEL_MAX_LINE];
        static size_t size = 0;

        char *newline;
        int line_size;

        BOOL result;
        ULONG bytes_read;

        result = WTSVirtualChannelRead(g_vchannel, 0, buffer + size,
                                       sizeof(buffer) - size, &bytes_read);

        if (!result) {
                errno = EIO;
                return -1;
        }

        if (overflow_mode) {
                newline = strchr(buffer, '\n');
                if (newline && (newline - buffer) < bytes_read) {
                        size = bytes_read - (newline - buffer) - 1;
                        memmove(buffer, newline + 1, size);
                        overflow_mode = FALSE;
                }
        }
        else
                size += bytes_read;

        if (overflow_mode) {
                errno = -EAGAIN;
                return -1;
        }

        newline = strchr(buffer, '\n');
        if (!newline || (newline - buffer) >= size) {
                if (size == sizeof(buffer)) {
                        overflow_mode = TRUE;
                        size = 0;
                }
                errno = -EAGAIN;
                return -1;
        }

        if ((newline - buffer) >= length) {
                errno = ENOMEM;
                return -1;
        }

        *newline = '\0';

        strcpy(line, buffer);
        line_size = newline - buffer;

        size -= newline - buffer + 1;
        memmove(buffer, newline + 1, size);

        return 0;
}

int
vchannel_write(char *format, ...)
{
        BOOL result;
        va_list argp;
        char buf[VCHANNEL_MAX_LINE];
        int size;
        ULONG bytes_written;

        assert(vchannel_is_open());

        va_start(argp, format);
        size = _vsnprintf(buf, sizeof(buf), format, argp);
        va_end(argp);

        assert(size < sizeof(buf));

        WaitForSingleObject(g_mutex, INFINITE);
        result = WTSVirtualChannelWrite(g_vchannel, buf, (ULONG) strlen(buf), &bytes_written);
        result = WTSVirtualChannelWrite(g_vchannel, "\n", (ULONG) 1, &bytes_written);
        ReleaseMutex(g_mutex);

        if (!result)
                return -1;

        return bytes_written;
}
1	/* -- c-basic-offset: 8 --
2	rdesktop: A Remote Desktop Protocol client.
3	Seamless windows - Virtual channel handling
4
5	Copyright (C) Pierre Ossman <ossman@cendio.se> 2006
6
7	This program is free software; you can redistribute it and/or modify
8	it under the terms of the GNU General Public License as published by
9	the Free Software Foundation; either version 2 of the License, or
10	(at your option) any later version.
11
12	This program is distributed in the hope that it will be useful,
13	but WITHOUT ANY WARRANTY; without even the implied warranty of
14	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15	GNU General Public License for more details.
16
17	You should have received a copy of the GNU General Public License
18	along with this program; if not, write to the Free Software
19	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20	*/
21
22	#include <assert.h>
23	#include <stdio.h>
24	#include <stdarg.h>
25	#include <errno.h>
26
27	#include <windows.h>
28	#include <wtsapi32.h>
29	#include <cchannel.h>
30
31	#include "vchannel.h"
32
33	#define CHANNELNAME "seamrdp"
34
35	static HANDLE g_mutex = NULL;
36	static HANDLE g_vchannel = NULL;
37
38	void
39	debug(char *format, ...)
40	{
41	va_list argp;
42	char buf[256];
43
44	sprintf(buf, "DEBUG1,");
45
46	va_start(argp, format);
47	_vsnprintf(buf + sizeof("DEBUG1,") - 1, sizeof(buf) - sizeof("DEBUG1,") + 1, format, argp);
48	va_end(argp);
49
50	vchannel_write(buf);
51	}
52
53
54	int
55	vchannel_open()
56	{
57	g_vchannel = WTSVirtualChannelOpen(WTS_CURRENT_SERVER_HANDLE,
58	WTS_CURRENT_SESSION, CHANNELNAME);
59
60	if (g_vchannel == NULL)
61	return -1;
62
63	g_mutex = CreateMutex(NULL, FALSE, "Local\\SeamlessChannel");
64	if (!g_mutex) {
65	WTSVirtualChannelClose(g_vchannel);
66	g_vchannel = NULL;
67	return -1;
68	}
69
70	return 0;
71	}
72
73	void
74	vchannel_close()
75	{
76	if (g_mutex)
77	CloseHandle(g_mutex);
78
79	if (g_vchannel)
80	WTSVirtualChannelClose(g_vchannel);
81
82	g_mutex = NULL;
83	g_vchannel = NULL;
84	}
85
86	int
87	vchannel_is_open()
88	{
89	if (g_vchannel == NULL)
90	return 0;
91	else
92	return 1;
93	}
94
95	int
96	vchannel_read(char *line, size_t length)
97	{
98	static BOOL overflow_mode = FALSE;
99	static char buffer[VCHANNEL_MAX_LINE];
100	static size_t size = 0;
101
102	char *newline;
103	int line_size;
104
105	BOOL result;
106	ULONG bytes_read;
107
108	result = WTSVirtualChannelRead(g_vchannel, 0, buffer + size,
109	sizeof(buffer) - size, &bytes_read);
110
111	if (!result) {
112	errno = EIO;
113	return -1;
114	}
115
116	if (overflow_mode) {
117	newline = strchr(buffer, '\n');
118	if (newline && (newline - buffer) < bytes_read) {
119	size = bytes_read - (newline - buffer) - 1;
120	memmove(buffer, newline + 1, size);
121	overflow_mode = FALSE;
122	}
123	}
124	else
125	size += bytes_read;
126
127	if (overflow_mode) {
128	errno = -EAGAIN;
129	return -1;
130	}
131
132	newline = strchr(buffer, '\n');
133	if (!newline \|\| (newline - buffer) >= size) {
134	if (size == sizeof(buffer)) {
135	overflow_mode = TRUE;
136	size = 0;
137	}
138	errno = -EAGAIN;
139	return -1;
140	}
141
142	if ((newline - buffer) >= length) {
143	errno = ENOMEM;
144	return -1;
145	}
146
147	*newline = '\0';
148
149	strcpy(line, buffer);
150	line_size = newline - buffer;
151
152	size -= newline - buffer + 1;
153	memmove(buffer, newline + 1, size);
154
155	return 0;
156	}
157
158	int
159	vchannel_write(char *format, ...)
160	{
161	BOOL result;
162	va_list argp;
163	char buf[VCHANNEL_MAX_LINE];
164	int size;
165	ULONG bytes_written;
166
167	assert(vchannel_is_open());
168
169	va_start(argp, format);
170	size = _vsnprintf(buf, sizeof(buf), format, argp);
171	va_end(argp);
172
173	assert(size < sizeof(buf));
174
175	WaitForSingleObject(g_mutex, INFINITE);
176	result = WTSVirtualChannelWrite(g_vchannel, buf, (ULONG) strlen(buf), &bytes_written);
177	result = WTSVirtualChannelWrite(g_vchannel, "\n", (ULONG) 1, &bytes_written);
178	ReleaseMutex(g_mutex);
179
180	if (!result)
181	return -1;
182
183	return bytes_written;
184	}