1/*
2 * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26//#define USE_ERROR
27//#define USE_TRACE
28
29#include "PLATFORM_API_LinuxOS_ALSA_CommonUtils.h"
30
31static void alsaDebugOutput(const char *file, int line, const char *function, int err, const char *fmt, ...) {
32#ifdef USE_ERROR
33    va_list args;
34    va_start(args, fmt);
35    printf("%s:%d function %s: error %d: %s\n", file, line, function, err, snd_strerror(err));
36    if (strlen(fmt) > 0) {
37        vprintf(fmt, args);
38    }
39    va_end(args);
40#endif
41}
42
43static int alsa_inited = 0;
44static int alsa_enumerate_pcm_subdevices = FALSE; // default: no
45static int alsa_enumerate_midi_subdevices = FALSE; // default: no
46
47/*
48 * Declare library specific JNI_Onload entry if static build
49 */
50DEF_STATIC_JNI_OnLoad
51
52void initAlsaSupport() {
53    char* enumerate;
54    if (!alsa_inited) {
55        alsa_inited = TRUE;
56        snd_lib_error_set_handler(&alsaDebugOutput);
57
58        enumerate = getenv(ENV_ENUMERATE_PCM_SUBDEVICES);
59        if (enumerate != NULL && strlen(enumerate) > 0
60            && (enumerate[0] != 'f')   // false
61            && (enumerate[0] != 'F')   // False
62            && (enumerate[0] != 'n')   // no
63            && (enumerate[0] != 'N')) { // NO
64            alsa_enumerate_pcm_subdevices = TRUE;
65        }
66#ifdef ALSA_MIDI_ENUMERATE_SUBDEVICES
67        alsa_enumerate_midi_subdevices = TRUE;
68#endif
69    }
70}
71
72
73/* if true (non-zero), ALSA sub devices should be listed as separate devices
74 */
75int needEnumerateSubdevices(int isMidi) {
76    initAlsaSupport();
77    return isMidi ? alsa_enumerate_midi_subdevices
78                  : alsa_enumerate_pcm_subdevices;
79}
80
81
82/*
83 * deviceID contains packed card, device and subdevice numbers
84 * each number takes 10 bits
85 * "default" device has id == ALSA_DEFAULT_DEVICE_ID
86 */
87UINT32 encodeDeviceID(int card, int device, int subdevice) {
88    return (((card & 0x3FF) << 20) | ((device & 0x3FF) << 10)
89           | (subdevice & 0x3FF)) + 1;
90}
91
92
93void decodeDeviceID(UINT32 deviceID, int* card, int* device, int* subdevice,
94                    int isMidi) {
95    deviceID--;
96    *card = (deviceID >> 20) & 0x3FF;
97    *device = (deviceID >> 10) & 0x3FF;
98    if (needEnumerateSubdevices(isMidi)) {
99        *subdevice = deviceID  & 0x3FF;
100    } else {
101        *subdevice = -1; // ALSA will choose any subdevices
102    }
103}
104
105
106void getDeviceString(char* buffer, int card, int device, int subdevice,
107                     int usePlugHw, int isMidi) {
108    if (needEnumerateSubdevices(isMidi)) {
109        sprintf(buffer, "%s:%d,%d,%d",
110                        usePlugHw ? ALSA_PLUGHARDWARE : ALSA_HARDWARE,
111                        card, device, subdevice);
112    } else {
113        sprintf(buffer, "%s:%d,%d",
114                        usePlugHw ? ALSA_PLUGHARDWARE : ALSA_HARDWARE,
115                        card, device);
116    }
117}
118
119
120void getDeviceStringFromDeviceID(char* buffer, UINT32 deviceID,
121                                 int usePlugHw, int isMidi) {
122    int card, device, subdevice;
123
124    if (deviceID == ALSA_DEFAULT_DEVICE_ID) {
125        strcpy(buffer, ALSA_DEFAULT_DEVICE_NAME);
126    } else {
127        decodeDeviceID(deviceID, &card, &device, &subdevice, isMidi);
128        getDeviceString(buffer, card, device, subdevice, usePlugHw, isMidi);
129    }
130}
131
132
133static int hasGottenALSAVersion = FALSE;
134#define ALSAVersionString_LENGTH 200
135static char ALSAVersionString[ALSAVersionString_LENGTH];
136
137void getALSAVersion(char* buffer, int len) {
138    if (!hasGottenALSAVersion) {
139        // get alsa version from proc interface
140        FILE* file;
141        int curr, len, totalLen, inVersionString;
142        file = fopen(ALSA_VERSION_PROC_FILE, "r");
143        ALSAVersionString[0] = 0;
144        if (file) {
145            if (NULL != fgets(ALSAVersionString, ALSAVersionString_LENGTH, file)) {
146                // parse for version number
147                totalLen = strlen(ALSAVersionString);
148                inVersionString = FALSE;
149                len = 0;
150                curr = 0;
151                while (curr < totalLen) {
152                    if (!inVersionString) {
153                        // is this char the beginning of a version string ?
154                        if (ALSAVersionString[curr] >= '0'
155                            && ALSAVersionString[curr] <= '9') {
156                            inVersionString = TRUE;
157                        }
158                    }
159                    if (inVersionString) {
160                        // the version string ends with white space
161                        if (ALSAVersionString[curr] <= 32) {
162                            break;
163                        }
164                        if (curr != len) {
165                            // copy this char to the beginning of the string
166                            ALSAVersionString[len] = ALSAVersionString[curr];
167                        }
168                        len++;
169                    }
170                    curr++;
171                }
172                // remove trailing dots
173                while ((len > 0) && (ALSAVersionString[len - 1] == '.')) {
174                    len--;
175                }
176                // null terminate
177                ALSAVersionString[len] = 0;
178            }
179            fclose(file);
180            hasGottenALSAVersion = TRUE;
181        }
182    }
183    strncpy(buffer, ALSAVersionString, len);
184}
185
186
187/* end */
188