aboutsummaryrefslogtreecommitdiffstats
path: root/src/mixer/plugins/OssMixerPlugin.cxx
blob: fc86f292e3fa8b8b998e670c35f18e2343e2cb5d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
/*
 * Copyright (C) 2003-2014 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"
#include "mixer/MixerInternal.hxx"
#include "config/ConfigData.hxx"
#include "system/fd_util.h"
#include "util/ASCII.hxx"
#include "util/Error.hxx"
#include "util/Domain.hxx"
#include "Log.hxx"

#include <assert.h>
#include <string.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>

#if defined(__OpenBSD__) || defined(__NetBSD__)
# include <soundcard.h>
#else /* !(defined(__OpenBSD__) || defined(__NetBSD__) */
# include <sys/soundcard.h>
#endif /* !(defined(__OpenBSD__) || defined(__NetBSD__) */

#define VOLUME_MIXER_OSS_DEFAULT		"/dev/mixer"

class OssMixer final : public Mixer {
	const char *device;
	const char *control;

	int device_fd;
	int volume_control;

public:
	OssMixer():Mixer(oss_mixer_plugin) {}

	bool Configure(const config_param &param, Error &error);

	/* virtual methods from class Mixer */
	virtual bool Open(Error &error) override;
	virtual void Close() override;
	virtual int GetVolume(Error &error) override;
	virtual bool SetVolume(unsigned volume, Error &error) override;
};

static constexpr Domain oss_mixer_domain("oss_mixer");

static int
oss_find_mixer(const char *name)
{
	const char *labels[SOUND_MIXER_NRDEVICES] = SOUND_DEVICE_LABELS;
	size_t name_length = strlen(name);

	for (unsigned i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
		if (StringEqualsCaseASCII(name, labels[i], name_length) &&
		    (labels[i][name_length] == 0 ||
		     labels[i][name_length] == ' '))
			return i;
	}
	return -1;
}

inline bool
OssMixer::Configure(const config_param &param, Error &error)
{
	device = param.GetBlockValue("mixer_device", VOLUME_MIXER_OSS_DEFAULT);
	control = param.GetBlockValue("mixer_control");

	if (control != NULL) {
		volume_control = oss_find_mixer(control);
		if (volume_control < 0) {
			error.Format(oss_mixer_domain, 0,
				     "no such mixer control: %s", control);
			return false;
		}
	} else
		volume_control = SOUND_MIXER_PCM;

	return true;
}

static Mixer *
oss_mixer_init(gcc_unused EventLoop &event_loop, gcc_unused void *ao,
	       const config_param &param,
	       Error &error)
{
	OssMixer *om = new OssMixer();

	if (!om->Configure(param, error)) {
		delete om;
		return nullptr;
	}

	return om;
}

void
OssMixer::Close()
{
	assert(device_fd >= 0);

	close(device_fd);
}

bool
OssMixer::Open(Error &error)
{
	device_fd = open_cloexec(device, O_RDONLY, 0);
	if (device_fd < 0) {
		error.FormatErrno("failed to open %s", device);
		return false;
	}

	if (control) {
		int devmask = 0;

		if (ioctl(device_fd, SOUND_MIXER_READ_DEVMASK, &devmask) < 0) {
			error.SetErrno("READ_DEVMASK failed");
			Close();
			return false;
		}

		if (((1 << volume_control) & devmask) == 0) {
			error.Format(oss_mixer_domain, 0,
				     "mixer control \"%s\" not usable",
				     control);
			Close();
			return false;
		}
	}

	return true;
}

int
OssMixer::GetVolume(Error &error)
{
	int left, right, level;
	int ret;

	assert(device_fd >= 0);

	ret = ioctl(device_fd, MIXER_READ(volume_control), &level);
	if (ret < 0) {
		error.SetErrno("failed to read OSS volume");
		return false;
	}

	left = level & 0xff;
	right = (level & 0xff00) >> 8;

	if (left != right) {
		FormatWarning(oss_mixer_domain,
			      "volume for left and right is not the same, \"%i\" and "
			      "\"%i\"\n", left, right);
	}

	return left;
}

bool
OssMixer::SetVolume(unsigned volume, Error &error)
{
	int level;
	int ret;

	assert(device_fd >= 0);
	assert(volume <= 100);

	level = (volume << 8) + volume;

	ret = ioctl(device_fd, MIXER_WRITE(volume_control), &level);
	if (ret < 0) {
		error.SetErrno("failed to set OSS volume");
		return false;
	}

	return true;
}

const MixerPlugin oss_mixer_plugin = {
	oss_mixer_init,
	true,
};