f1c1e8f131f3500a326f8832c1d332c9d17cbbac
[paraslash.git] / write_common.c
1 /*
2 * Copyright (C) 2006-2007 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file write_common.c common functions of para_audiod and para_write */
20
21 #include "para.h"
22 #include "string.h"
23 #include "list.h"
24 #include "sched.h"
25 #include "write.h"
26 #include "error.h"
27
28 /** the array containing the names of all supported writers */
29 const char *writer_names[] ={WRITER_NAMES};
30
31 /** the array of supported writers */
32 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
33
34 static void wng_pre_select(__a_unused struct sched *s, struct task *t)
35 {
36 struct writer_node_group *g = t->private_data;
37 int i;
38
39 FOR_EACH_WRITER_NODE(i, g) {
40 struct writer_node *wn = &g->writer_nodes[i];
41 t->ret = wn->writer->pre_select(s, wn);
42 if (t->ret < 0) {
43 g->eof = 1;
44 return;
45 }
46 }
47 }
48
49 static void wng_post_select(struct sched *s, struct task *t)
50 {
51 struct writer_node_group *g = t->private_data;
52 int i;
53 size_t min_written = 0;
54
55 FOR_EACH_WRITER_NODE(i, g) {
56 struct writer_node *wn = &g->writer_nodes[i];
57 t->ret = wn->writer->post_select(s, wn);
58 if (t->ret < 0) {
59 g->eof = 1;
60 return;
61 }
62 if (!i)
63 min_written = wn->written;
64 else
65 min_written = PARA_MIN(min_written, wn->written);
66 }
67 // PARA_INFO_LOG("loaded: %zd, min_written: %zd bytes\n", *g->loaded, min_written);
68 if (min_written) {
69 *g->loaded -= min_written;
70 FOR_EACH_WRITER_NODE(i, g)
71 g->writer_nodes[i].written -= min_written;
72 }
73 if (!*g->loaded && *g->input_eof) {
74 g->eof = 1;
75 t->ret = -E_WNG_EOF;
76 return;
77 }
78 t->ret = 1;
79 if (*g->loaded && min_written) {
80 // PARA_INFO_LOG("moving %zd bytes\n", *g->loaded);
81 memmove(g->buf, g->buf + min_written, *g->loaded);
82 }
83 }
84
85 /**
86 * call the open function of each writer in the group
87 *
88 * \param g the writer node group
89 *
90 * \return If at least one open function returned an error, all successful
91 * writer notes get closed and this error value is returned. Upon success, a
92 * task associated with \a g is registered to the scheduler and the function
93 * returnes a positive value.
94 * */
95 int wng_open(struct writer_node_group *g)
96 {
97 int i, ret = 1;
98
99 PARA_NOTICE_LOG("opening wng %p with %d writer(s)\n", g, g->num_writers);
100 register_task(&g->task);
101 FOR_EACH_WRITER_NODE(i, g) {
102 struct writer_node *wn = &g->writer_nodes[i];
103 wn->wng = g;
104 ret = wn->writer->open(wn);
105 if (ret < 0)
106 goto err_out;
107 wn->chunk_bytes = ret;
108 g->max_chunk_bytes = PARA_MAX(g->max_chunk_bytes, ret);
109 }
110 sprintf(g->task.status, "%s", "writer node group");
111 g->eof = 0;
112 return 1;
113 err_out:
114 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
115 unregister_task(&g->task);
116 while (i > 0) {
117 struct writer_node *wn = &g->writer_nodes[--i];
118 wn->writer->close(wn);
119 }
120 g->num_writers = 0;
121 g->eof = 1;
122 return ret;
123 }
124
125
126 /**
127 * unregister a writer node group task
128 *
129 * \param g the group whose task is to be closed
130 */
131 void wng_unregister(struct writer_node_group *g)
132 {
133 unregister_task(&g->task);
134 g->eof = 1;
135 }
136
137 /**
138 * call the close function of each writer in the given group
139 *
140 * \param g the writer node group to close
141 *
142 * This function also frees all resources of the given group.
143 */
144 void wng_close(struct writer_node_group *g)
145 {
146 int i;
147
148 if (!g)
149 return;
150 PARA_NOTICE_LOG("closing wng with %d writer(s)\n", g->num_writers);
151 FOR_EACH_WRITER_NODE(i, g) {
152 struct writer_node *wn = &g->writer_nodes[i];
153 wn->writer->close(wn);
154 }
155 free(g->writer_nodes);
156 free(g);
157 }
158
159 /**
160 * allocate and initialize a new writer_node_group struct
161 *
162 * \param num_writers the number of writer nodes for the new group
163 *
164 * \return Pointer to the new writer node group
165 */
166 struct writer_node_group *wng_new(unsigned num_writers)
167 {
168 struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
169 g->num_writers = num_writers;
170 g->writer_nodes = para_calloc(num_writers
171 * sizeof(struct writer_node));
172 g->task.private_data = g;
173 g->task.post_select = wng_post_select;
174 g->task.pre_select = wng_pre_select;
175 return g;
176 }
177
178 /**
179 * call the init function of each supported paraslash writer
180 */
181 void init_supported_writers(void)
182 {
183 int i;
184
185 FOR_EACH_WRITER(i)
186 writers[i].init(&writers[i]);
187 }
188 /**
189 * check if given string is a valid command line for any writer
190 *
191 * \param \wa string of the form writer_name:options
192 * \param writer_num contains the number of the writer upon success
193 *
194 * This function checks whether \a wa starts with the name of a supported
195 * paraslash writer, optinally followed by a colon and any options for that
196 * writer. If a valid writer name was found and further are present, the
197 * remaining part of \a wa is passed to that writer's config parser.
198 *
199 * \return On success, a pointer to the gengetopt args info struct is returned
200 * and \a writer_num contains the number of the writer. Otherwise this function
201 * returns \p NULL.
202 */
203 void *check_writer_arg(const char *wa, int *writer_num)
204 {
205 int i;
206
207 *writer_num = -E_WRITE_COMMON_SYNTAX;
208 PARA_INFO_LOG("checking %s\n", wa);
209 FOR_EACH_WRITER(i) {
210 const char *name = writer_names[i];
211 size_t len = strlen(name);
212 char c;
213 if (strlen(wa) < len)
214 continue;
215 if (strncmp(name, wa, len))
216 continue;
217 c = wa[len];
218 if (c && c != ' ')
219 continue;
220 if (c && !writers[i].parse_config)
221 return NULL;
222 *writer_num = i;
223 return writers[i].parse_config(c? wa + len + 1 : "");
224 }
225 PARA_ERROR_LOG("%s", "writer not found\n");
226 return NULL;
227 }
228
229 /**
230 * setup a writer node group with only one writer, the default writer
231 *
232 * The writer which is set up depends on the OS. It defaults to alsa for Linux,
233 * osx_write for OS X, file writer if neither of these is supported.
234 *
235 * \return pointer to the allocated writer node group
236 */
237 struct writer_node_group *setup_default_wng(void)
238 {
239 struct writer_node_group *wng = wng_new(1);
240 wng->writer_nodes[0].writer = &writers[DEFAULT_WRITER];
241 PARA_INFO_LOG("using default writer: %s %p\n",
242 writer_names[DEFAULT_WRITER], writers[DEFAULT_WRITER].parse_config);
243 wng->writer_nodes[0].conf = writers[DEFAULT_WRITER].parse_config("");
244 return wng;
245 }