1 /**
2  * \file include/conf.h
3  * \brief Application interface library for the ALSA driver
4  * \author Jaroslav Kysela <perex@perex.cz>
5  * \author Abramo Bagnara <abramo@alsa-project.org>
6  * \author Takashi Iwai <tiwai@suse.de>
7  * \date 1998-2001
8  *
9  * Application interface library for the ALSA driver
10  */
11 /*
12  *   This library is free software; you can redistribute it and/or modify
13  *   it under the terms of the GNU Lesser General Public License as
14  *   published by the Free Software Foundation; either version 2.1 of
15  *   the License, or (at your option) any later version.
16  *
17  *   This program is distributed in the hope that it will be useful,
18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *   GNU Lesser General Public License for more details.
21  *
22  *   You should have received a copy of the GNU Lesser General Public
23  *   License along with this library; if not, write to the Free Software
24  *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
25  *
26  */
27 
28 #ifndef __ALSA_CONF_H
29 #define __ALSA_CONF_H
30 
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34 
35 /**
36  *  \defgroup Configuration Configuration Interface
37  *  The configuration functions and types allow you to read, enumerate,
38  *  modify and write the contents of ALSA configuration files.
39  *  \{
40  */
41 
42 /** \brief \c dlsym version for the config evaluate callback. */
43 #define SND_CONFIG_DLSYM_VERSION_EVALUATE	_dlsym_config_evaluate_001
44 /** \brief \c dlsym version for the config hook callback. */
45 #define SND_CONFIG_DLSYM_VERSION_HOOK		_dlsym_config_hook_001
46 
47 /** \brief Configuration node type. */
48 typedef enum _snd_config_type {
49 	/** Integer number. */
50         SND_CONFIG_TYPE_INTEGER,
51 	/** 64-bit integer number. */
52         SND_CONFIG_TYPE_INTEGER64,
53 	/** Real number. */
54         SND_CONFIG_TYPE_REAL,
55 	/** Character string. */
56         SND_CONFIG_TYPE_STRING,
57         /** Pointer (runtime only, cannot be saved). */
58         SND_CONFIG_TYPE_POINTER,
59 	/** Compound node. */
60 	SND_CONFIG_TYPE_COMPOUND = 1024
61 } snd_config_type_t;
62 
63 /**
64  * \brief Internal structure for a configuration node object.
65  *
66  * The ALSA library uses a pointer to this structure as a handle to a
67  * configuration node. Applications don't access its contents directly.
68  */
69 typedef struct _snd_config snd_config_t;
70 /**
71  * \brief Type for a configuration compound iterator.
72  *
73  * The ALSA library uses this pointer type as a handle to a configuration
74  * compound iterator. Applications don't directly access the contents of
75  * the structure pointed to by this type.
76  */
77 typedef struct _snd_config_iterator *snd_config_iterator_t;
78 /**
79  * \brief Internal structure for a configuration private update object.
80  *
81  * The ALSA library uses this structure to save private update information.
82  */
83 typedef struct _snd_config_update snd_config_update_t;
84 
85 extern snd_config_t *snd_config;
86 
87 const char *snd_config_topdir(void);
88 
89 int snd_config_top(snd_config_t **config);
90 
91 int snd_config_load(snd_config_t *config, snd_input_t *in);
92 int snd_config_load_string(snd_config_t **config, const char *s, size_t size);
93 int snd_config_load_override(snd_config_t *config, snd_input_t *in);
94 int snd_config_save(snd_config_t *config, snd_output_t *out);
95 int snd_config_update(void);
96 int snd_config_update_r(snd_config_t **top, snd_config_update_t **update, const char *path);
97 int snd_config_update_free(snd_config_update_t *update);
98 int snd_config_update_free_global(void);
99 
100 int snd_config_update_ref(snd_config_t **top);
101 void snd_config_ref(snd_config_t *top);
102 void snd_config_unref(snd_config_t *top);
103 
104 int snd_config_search(snd_config_t *config, const char *key,
105 		      snd_config_t **result);
106 int snd_config_searchv(snd_config_t *config,
107 		       snd_config_t **result, ...);
108 int snd_config_search_definition(snd_config_t *config,
109 				 const char *base, const char *key,
110 				 snd_config_t **result);
111 
112 /**
113  * \brief custom expansion callback
114  * \param[out] dst The function puts the handle to the new configuration
115  *                 node at the address specified by \a dst.
116  * \param[in] s string the string to be expanded
117  * \param[in] private_data Handle to the \c private_data node.
118  * \return A non-negative value if successful, otherwise a negative error code.
119  *
120  * Use a function of this type to define a custom expansion
121  */
122 typedef int (*snd_config_expand_fcn_t)(snd_config_t **dst, const char *s, void *private_data);
123 
124 int snd_config_expand_custom(snd_config_t *config, snd_config_t *root,
125 			     snd_config_expand_fcn_t fcn, void *private_data,
126 			     snd_config_t **result);
127 int snd_config_expand(snd_config_t *config, snd_config_t *root,
128 		      const char *args, snd_config_t *private_data,
129 		      snd_config_t **result);
130 int snd_config_evaluate(snd_config_t *config, snd_config_t *root,
131 			snd_config_t *private_data, snd_config_t **result);
132 int snd_config_evaluate_string(snd_config_t **dst, const char *s,
133 			       snd_config_expand_fcn_t fcn, void *private_data);
134 
135 int snd_config_add(snd_config_t *config, snd_config_t *child);
136 int snd_config_add_before(snd_config_t *before, snd_config_t *child);
137 int snd_config_add_after(snd_config_t *after, snd_config_t *child);
138 int snd_config_remove(snd_config_t *config);
139 int snd_config_delete(snd_config_t *config);
140 int snd_config_delete_compound_members(const snd_config_t *config);
141 int snd_config_copy(snd_config_t **dst, snd_config_t *src);
142 int snd_config_substitute(snd_config_t *dst, snd_config_t *src);
143 int snd_config_merge(snd_config_t *dst, snd_config_t *src, int override);
144 
145 int snd_config_make(snd_config_t **config, const char *key,
146 		    snd_config_type_t type);
147 int snd_config_make_integer(snd_config_t **config, const char *key);
148 int snd_config_make_integer64(snd_config_t **config, const char *key);
149 int snd_config_make_real(snd_config_t **config, const char *key);
150 int snd_config_make_string(snd_config_t **config, const char *key);
151 int snd_config_make_pointer(snd_config_t **config, const char *key);
152 int snd_config_make_compound(snd_config_t **config, const char *key, int join);
153 int snd_config_make_path(snd_config_t **config, snd_config_t *root, const char *key,
154 			 int join, int override);
155 
156 int snd_config_imake_integer(snd_config_t **config, const char *key, const long value);
157 int snd_config_imake_integer64(snd_config_t **config, const char *key, const long long value);
158 int snd_config_imake_real(snd_config_t **config, const char *key, const double value);
159 int snd_config_imake_string(snd_config_t **config, const char *key, const char *ascii);
160 int snd_config_imake_safe_string(snd_config_t **config, const char *key, const char *ascii);
161 int snd_config_imake_pointer(snd_config_t **config, const char *key, const void *ptr);
162 
163 snd_config_type_t snd_config_get_type(const snd_config_t *config);
164 int snd_config_is_array(const snd_config_t *config);
165 int snd_config_is_empty(const snd_config_t *config);
166 
167 int snd_config_set_id(snd_config_t *config, const char *id);
168 int snd_config_set_integer(snd_config_t *config, long value);
169 int snd_config_set_integer64(snd_config_t *config, long long value);
170 int snd_config_set_real(snd_config_t *config, double value);
171 int snd_config_set_string(snd_config_t *config, const char *value);
172 int snd_config_set_ascii(snd_config_t *config, const char *ascii);
173 int snd_config_set_pointer(snd_config_t *config, const void *ptr);
174 int snd_config_get_id(const snd_config_t *config, const char **value);
175 int snd_config_get_integer(const snd_config_t *config, long *value);
176 int snd_config_get_integer64(const snd_config_t *config, long long *value);
177 int snd_config_get_real(const snd_config_t *config, double *value);
178 int snd_config_get_ireal(const snd_config_t *config, double *value);
179 int snd_config_get_string(const snd_config_t *config, const char **value);
180 int snd_config_get_ascii(const snd_config_t *config, char **value);
181 int snd_config_get_pointer(const snd_config_t *config, const void **value);
182 int snd_config_test_id(const snd_config_t *config, const char *id);
183 
184 snd_config_iterator_t snd_config_iterator_first(const snd_config_t *node);
185 snd_config_iterator_t snd_config_iterator_next(const snd_config_iterator_t iterator);
186 snd_config_iterator_t snd_config_iterator_end(const snd_config_t *node);
187 snd_config_t *snd_config_iterator_entry(const snd_config_iterator_t iterator);
188 
189 /**
190  * \brief Helper macro to iterate over the children of a compound node.
191  * \param[in,out] pos Iterator variable for the current node.
192  * \param[in,out] next Temporary iterator variable for the next node.
193  * \param[in] node Handle to the compound configuration node to iterate over.
194  *
195  * Use this macro like a \c for statement, e.g.:
196  * \code
197  * snd_config_iterator_t pos, next;
198  * snd_config_for_each(pos, next, node) {
199  *     snd_config_t *entry = snd_config_iterator_entry(pos);
200  *     ...
201  * }
202  * \endcode
203  *
204  * This macro allows deleting or removing the current node.
205  */
206 #define snd_config_for_each(pos, next, node) \
207 	for (pos = snd_config_iterator_first(node), next = snd_config_iterator_next(pos); pos != snd_config_iterator_end(node); pos = next, next = snd_config_iterator_next(pos))
208 
209 /* Misc functions */
210 
211 int snd_config_get_bool_ascii(const char *ascii);
212 int snd_config_get_bool(const snd_config_t *conf);
213 int snd_config_get_card(const snd_config_t *conf);
214 int snd_config_get_ctl_iface_ascii(const char *ascii);
215 int snd_config_get_ctl_iface(const snd_config_t *conf);
216 
217 /* Names functions */
218 
219 /**
220  * Device-name list element
221  */
222 typedef struct snd_devname snd_devname_t;
223 
224 /**
225  * Device-name list element (definition)
226  */
227 struct snd_devname {
228 	char *name;	/**< Device name string */
229 	char *comment;	/**< Comments */
230 	snd_devname_t *next;	/**< Next pointer */
231 };
232 
233 int snd_names_list(const char *iface, snd_devname_t **list);
234 void snd_names_list_free(snd_devname_t *list);
235 
236 /** \} */
237 
238 #ifdef __cplusplus
239 }
240 #endif
241 
242 #endif /* __ALSA_CONF_H */
243