first version of the universal paraslash scheduler
[paraslash.git] / write_common.c
1 /*
2 * Copyright (C) 2006 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 const char *writer_names[] ={WRITER_NAMES};
29 struct writer writers[NUM_SUPPORTED_WRITERS] = {WRITER_ARRAY};
30
31 int wng_write(struct writer_node_group *g, char *buf, size_t *loaded)
32 {
33 int ret, i, need_more_writes = 1;
34 size_t min_written = 0;
35
36 while (need_more_writes) {
37 need_more_writes = 0;
38 FOR_EACH_WRITER_NODE(i, g) {
39 size_t w = g->written[i];
40 int bytes_to_write;
41 struct writer_node *wn = &g->writer_nodes[i];
42 if (!i)
43 min_written = w;
44 else
45 min_written = PARA_MIN(min_written, w);
46 if (w == *loaded)
47 continue;
48 if (!g->eof && (*loaded < wn->chunk_bytes + w))
49 continue;
50 bytes_to_write = PARA_MIN(wn->chunk_bytes,
51 *loaded - w);
52 ret = wn->writer->write(buf + w, bytes_to_write, wn);
53 if (ret < 0)
54 goto out;
55 if (ret != bytes_to_write)
56 PARA_WARNING_LOG("short write: %d/%d\n", ret,
57 bytes_to_write);
58 g->written[i] += ret;
59 need_more_writes = 1;
60 }
61 }
62 *loaded -= min_written;
63 ret = 0;
64 if (g->eof)
65 goto out;
66 if (*loaded)
67 memmove(buf, buf + min_written, *loaded);
68 FOR_EACH_WRITER_NODE(i, g)
69 g->written[i] -= min_written;
70 ret = 1;
71 out:
72 return ret;
73 }
74
75 static void wng_post_select(struct sched *s, struct task *t)
76 {
77 struct writer_node_group *g = t->private_data;
78 int i;
79 size_t min_written = 0;
80
81 FOR_EACH_WRITER_NODE(i, g) {
82 struct writer_node *wn = &g->writer_nodes[i];
83 t->ret = wn->task.ret;
84 if (t->ret < 0)
85 return;
86 if (!i)
87 min_written = t->ret;
88 else
89 min_written = PARA_MIN(min_written, t->ret);
90 }
91 *g->loaded -= min_written;
92 if (!*g->loaded && g->eof)
93 t->ret = 0;
94 else
95 t->ret = 1;
96 if (*g->loaded && min_written)
97 memmove(g->buf, g->buf + min_written, *g->loaded);
98 }
99
100 int wng_open(struct writer_node_group *g)
101 {
102 int i, ret = 1;
103
104 FOR_EACH_WRITER_NODE(i, g) {
105 struct writer_node *wn = &g->writer_nodes[i];
106 ret = wn->writer->open(wn);
107 if (ret < 0)
108 goto out;
109 wn->chunk_bytes = ret;
110 g->max_chunk_bytes = PARA_MAX(g->max_chunk_bytes, ret);
111 wn->wng = g;
112 PARA_DEBUG_LOG("pre_select: %p\n", &wn->writer->pre_select);
113 PARA_DEBUG_LOG("post_select: %p\n", &wn->writer->post_select);
114 wn->task.pre_select = wn->writer->pre_select;
115 wn->task.post_select = wn->writer->post_select;
116 wn->task.private_data = wn;
117 register_task(&wn->task);
118 }
119 register_task(&g->task);
120 out:
121 return ret;
122 }
123
124 void wng_destroy(struct writer_node_group *g)
125 {
126 if (!g)
127 return;
128 free(g->written);
129 free(g->writer_nodes);
130 free(g);
131 }
132
133 void wng_close(struct writer_node_group *g)
134 {
135 int i;
136
137 FOR_EACH_WRITER_NODE(i, g) {
138 struct writer_node *wn = &g->writer_nodes[i];
139 unregister_task(&wn->task);
140 wn->writer->close(wn);
141 }
142 }
143
144 static void wng_error_handler(struct task *t)
145 {
146 struct writer_node_group *g = t->private_data;
147
148 PARA_INFO_LOG("%p: ret = %d\n", t, t->ret);
149 unregister_task(t);
150 wng_close(g);
151 wng_destroy(g);
152 }
153
154 struct writer_node_group *wng_new(unsigned num_writers)
155 {
156 struct writer_node_group *g = para_calloc(sizeof(struct writer_node_group));
157 g->num_writers = num_writers;
158 g->writer_nodes = para_calloc(num_writers
159 * sizeof(struct writer_node));
160 g->written = para_calloc(num_writers * sizeof(size_t));
161 g->task.private_data = g;
162 g->task.post_select = wng_post_select;
163 g->task.error_handler = wng_error_handler;
164 g->task.flags = POST_ADD_TAIL | POST_EOF_IS_ERROR;
165 return g;
166 }
167
168 void init_supported_writers(void)
169 {
170 int i;
171
172 FOR_EACH_WRITER(i)
173 writers[i].init(&writers[i]);
174 }
175
176 int check_writer_arg(const char *arg)
177 {
178 int i, ret = -E_WRITE_COMMON_SYNTAX;
179 char *a = para_strdup(arg), *p = strchr(a, ':');
180 if (p)
181 *p = '\0';
182 p++;
183 FOR_EACH_WRITER(i) {
184 if (strcmp(writer_names[i], a))
185 continue;
186 ret = i;
187 goto out;
188 }
189 out:
190 free(a);
191 return ret;
192 }
193
194 struct writer_node_group *setup_default_wng(void)
195 {
196 struct writer_node_group *wng = wng_new(1);
197 enum writer_enum default_writer;
198
199 if (NUM_SUPPORTED_WRITERS == 1)
200 default_writer = FILE_WRITE;
201 else
202 default_writer = 1;
203 wng->writer_nodes[0].writer = &writers[default_writer];
204 PARA_INFO_LOG("using default writer: %s\n",
205 writer_names[default_writer]);
206 return wng;
207 }