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;
}

void
vchannel_block()
{
        WaitForSingleObject(g_mutex, INFINITE);
}

void
vchannel_unblock()
{
        ReleaseMutex(g_mutex);
}
1	ossman_	1073	/* -- 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	ossman_	1074	#include <errno.h>
26	ossman_	1073
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	ossman_	1078	if (!g_mutex)
65			{
66	ossman_	1073	WTSVirtualChannelClose(g_vchannel);
67			g_vchannel = NULL;
68			return -1;
69			}
70
71			return 0;
72			}
73
74			void
75			vchannel_close()
76			{
77			if (g_mutex)
78			CloseHandle(g_mutex);
79
80			if (g_vchannel)
81			WTSVirtualChannelClose(g_vchannel);
82
83			g_mutex = NULL;
84			g_vchannel = NULL;
85			}
86
87			int
88			vchannel_is_open()
89			{
90			if (g_vchannel == NULL)
91			return 0;
92			else
93			return 1;
94			}
95
96			int
97	ossman_	1074	vchannel_read(char *line, size_t length)
98	ossman_	1073	{
99	ossman_	1074	static BOOL overflow_mode = FALSE;
100			static char buffer[VCHANNEL_MAX_LINE];
101			static size_t size = 0;
102
103			char *newline;
104			int line_size;
105
106			BOOL result;
107			ULONG bytes_read;
108
109			result = WTSVirtualChannelRead(g_vchannel, 0, buffer + size,
110			sizeof(buffer) - size, &bytes_read);
111
112	ossman_	1078	if (!result)
113			{
114	ossman_	1074	errno = EIO;
115			return -1;
116			}
117
118	ossman_	1078	if (overflow_mode)
119			{
120	ossman_	1074	newline = strchr(buffer, '\n');
121	ossman_	1078	if (newline && (newline - buffer) < bytes_read)
122			{
123	ossman_	1074	size = bytes_read - (newline - buffer) - 1;
124			memmove(buffer, newline + 1, size);
125			overflow_mode = FALSE;
126			}
127			}
128			else
129			size += bytes_read;
130
131	ossman_	1078	if (overflow_mode)
132			{
133	ossman_	1074	errno = -EAGAIN;
134			return -1;
135			}
136
137			newline = strchr(buffer, '\n');
138	ossman_	1078	if (!newline \|\| (newline - buffer) >= size)
139			{
140			if (size == sizeof(buffer))
141			{
142	ossman_	1074	overflow_mode = TRUE;
143			size = 0;
144			}
145			errno = -EAGAIN;
146			return -1;
147			}
148
149	ossman_	1078	if ((newline - buffer) >= length)
150			{
151	ossman_	1074	errno = ENOMEM;
152			return -1;
153			}
154
155			*newline = '\0';
156
157			strcpy(line, buffer);
158			line_size = newline - buffer;
159
160			size -= newline - buffer + 1;
161			memmove(buffer, newline + 1, size);
162
163			return 0;
164	ossman_	1073	}
165
166			int
167			vchannel_write(char *format, ...)
168			{
169			BOOL result;
170			va_list argp;
171	ossman_	1074	char buf[VCHANNEL_MAX_LINE];
172	ossman_	1073	int size;
173			ULONG bytes_written;
174
175			assert(vchannel_is_open());
176
177			va_start(argp, format);
178			size = _vsnprintf(buf, sizeof(buf), format, argp);
179			va_end(argp);
180
181			assert(size < sizeof(buf));
182
183			WaitForSingleObject(g_mutex, INFINITE);
184			result = WTSVirtualChannelWrite(g_vchannel, buf, (ULONG) strlen(buf), &bytes_written);
185			result = WTSVirtualChannelWrite(g_vchannel, "\n", (ULONG) 1, &bytes_written);
186			ReleaseMutex(g_mutex);
187
188			if (!result)
189			return -1;
190
191			return bytes_written;
192			}
193	ossman_	1075
194			void
195			vchannel_block()
196			{
197			WaitForSingleObject(g_mutex, INFINITE);
198			}
199
200			void
201			vchannel_unblock()
202			{
203			ReleaseMutex(g_mutex);
204			}