audiod: Properly handle wng open failures.
[paraslash.git] / write_common.c
1 /*
2  * Copyright (C) 2006-2009 Andre Noll <maan@systemlinux.org>
3  *
4  * Licensed under the GPL v2. For licencing details see COPYING.
5  */
6
7 /** \file write_common.c common functions of para_audiod and para_write */
8
9 #include "para.h"
10 #include "string.h"
11 #include "list.h"
12 #include "sched.h"
13 #include "ggo.h"
14 #include "write.h"
15 #include "error.h"
16
17 /** the array containing the names of all supported writers */
18 const char *writer_names[] ={WRITER_NAMES};
19
20 /** the array of supported writers */
21 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
22
23 static void wng_pre_select(__a_unused struct sched *s, struct task *t)
24 {
25         struct writer_node_group *g = container_of(t, struct writer_node_group, task);
26         int i;
27
28         FOR_EACH_WRITER_NODE(i, g) {
29                 struct writer_node *wn = &g->writer_nodes[i];
30                 if (!wn->writer->pre_select)
31                         continue;
32                 t->error = wn->writer->pre_select(s, wn);
33                 if (t->error < 0)
34                         return;
35         }
36 }
37
38 static void wng_post_select(struct sched *s, struct task *t)
39 {
40         struct writer_node_group *g = container_of(t, struct writer_node_group, task);
41         int i;
42         size_t min_written = 0;
43
44         FOR_EACH_WRITER_NODE(i, g) {
45                 struct writer_node *wn = &g->writer_nodes[i];
46                 t->error = wn->writer->post_select(s, wn);
47                 if (t->error < 0)
48                         return;
49                 if (!i)
50                         min_written = wn->written;
51                 else
52                         min_written = PARA_MIN(min_written, wn->written);
53         }
54         //PARA_INFO_LOG("loaded: %zd, min_written: %zd bytes\n", *g->loaded, min_written);
55         if (min_written) {
56                 *g->loaded -= min_written;
57                 FOR_EACH_WRITER_NODE(i, g)
58                         g->writer_nodes[i].written -= min_written;
59         }
60         if (!*g->loaded && *g->input_error) {
61                 t->error = *g->input_error;
62                 return;
63         }
64         if (*g->loaded && min_written) {
65 //              PARA_INFO_LOG("moving %zd bytes\n", *g->loaded);
66                 memmove(*g->bufp, *g->bufp + min_written, *g->loaded);
67         }
68 }
69
70 /**
71  * call the open function of each writer in the group
72  *
73  * \param g the writer node group
74  *
75  * \return If at least one open function returned an error, all successful
76  * writer notes get closed and this error value is returned. Upon success, a
77  * task associated with \a g is registered to the scheduler and the function
78  * returns a positive value.
79  * */
80 int wng_open(struct writer_node_group *g)
81 {
82         int i, ret = 1;
83
84         PARA_NOTICE_LOG("opening wng %p with %d writer(s)\n", g, g->num_writers);
85         FOR_EACH_WRITER_NODE(i, g) {
86                 struct writer_node *wn = &g->writer_nodes[i];
87                 wn->wng = g;
88                 ret = wn->writer->open(wn);
89                 if (ret < 0)
90                         goto err_out;
91         }
92         sprintf(g->task.status, "%s", "writer node group");
93         register_task(&g->task);
94         g->open = 1;
95         return 1;
96 err_out:
97         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
98         while (i > 0) {
99                 struct writer_node *wn = &g->writer_nodes[--i];
100                 wn->writer->close(wn);
101         }
102         free(g->writer_nodes);
103         g->num_writers = 0;
104         g->task.error = -E_TASK_UNREGISTERED;
105         return ret;
106 }
107
108 /**
109  * call the close function of each writer in the given group
110  *
111  * \param g the writer node group to close
112  *
113  * This function also frees all resources of the given group.
114  */
115 void wng_close(struct writer_node_group *g)
116 {
117         int i;
118
119         if (!g || !g->open)
120                 return;
121         PARA_NOTICE_LOG("closing wng with %d writer(s)\n", g->num_writers);
122         FOR_EACH_WRITER_NODE(i, g) {
123                 struct writer_node *wn = &g->writer_nodes[i];
124                 wn->writer->close(wn);
125         }
126         free(g->writer_nodes);
127         free(g);
128 }
129
130 /**
131  * allocate and initialize a new writer_node_group struct
132  *
133  * \param num_writers the number of writer nodes for the new group
134  *
135  * \return Pointer to the new writer node group
136  */
137 struct writer_node_group *wng_new(unsigned num_writers)
138 {
139         struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
140         g->num_writers = num_writers;
141         g->writer_nodes = para_calloc(num_writers
142                 * sizeof(struct writer_node));
143         g->task.post_select = wng_post_select;
144         g->task.pre_select = wng_pre_select;
145         return g;
146 }
147
148 /**
149  * Call the init function of each supported paraslash writer.
150  */
151 void writer_init(void)
152 {
153         int i;
154
155         FOR_EACH_WRITER(i)
156                 writers[i].init(&writers[i]);
157 }
158 /**
159  * check if given string is a valid command line for any writer
160  *
161  * \param \wa string of the form writer_name:options
162  * \param writer_num contains the number of the writer upon success
163  *
164  * This function checks whether \a wa starts with the name of a supported
165  * paraslash writer, optionally followed by a colon and any options for that
166  * writer.  If a valid writer name was found and further are present, the
167  * remaining part of \a wa is passed to that writer's config parser.
168  *
169  * \return On success, a pointer to the gengetopt args info struct is returned
170  * and \a writer_num contains the number of the writer. Otherwise this function
171  * returns \p NULL.
172  */
173 void *check_writer_arg(const char *wa, int *writer_num)
174 {
175         int i;
176
177         *writer_num = -E_WRITE_COMMON_SYNTAX;
178         PARA_INFO_LOG("checking  %s\n", wa);
179         FOR_EACH_WRITER(i) {
180                 const char *name = writer_names[i];
181                 size_t len = strlen(name);
182                 char c;
183                 if (strlen(wa) < len)
184                         continue;
185                 if (strncmp(name, wa, len))
186                         continue;
187                 c = wa[len];
188                 if (c && c != ' ')
189                         continue;
190                 if (c && !writers[i].parse_config)
191                         return NULL;
192                 *writer_num = i;
193                 return writers[i].parse_config(c? wa + len + 1 : "");
194         }
195         PARA_ERROR_LOG("writer not found\n");
196         return NULL;
197 }
198
199 /**
200  * setup a writer node group with only one writer, the default writer
201  *
202  * The writer which is set up depends on the OS. It defaults to alsa for Linux,
203  * osx_write for OS X, file writer if neither of these is supported.
204  *
205  * \return pointer to the allocated writer node group
206  */
207 struct writer_node_group *setup_default_wng(void)
208 {
209         struct writer_node_group *wng = wng_new(1);
210         wng->writer_nodes[0].writer = &writers[DEFAULT_WRITER];
211         PARA_INFO_LOG("using default writer: %s %p\n",
212                 writer_names[DEFAULT_WRITER], writers[DEFAULT_WRITER].parse_config);
213         wng->writer_nodes[0].conf = writers[DEFAULT_WRITER].parse_config("");
214         return wng;
215 }
216
217 void print_writer_helps(int detailed)
218 {
219         int i;
220
221         printf_or_die("\nAvailable writers: \n\t");
222         FOR_EACH_WRITER(i)
223                 printf_or_die("%s%s", i? " " : "", writer_names[i]);
224         printf_or_die("\n\n");
225         FOR_EACH_WRITER(i) {
226                 struct writer *w = writers + i;
227
228                 if (!w->help.short_help)
229                         continue;
230                 printf_or_die("Options for %s:\n", writer_names[i]);
231                 ggo_print_help(&w->help, detailed);
232         }
233 }