207d33245947e1b4ef898d3906c8045d76081a9e
[paraslash.git] / prebuffer_filter.c
1 /*
2 * Copyright (C) 2009 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file prebuffer_filter.c Paraslash's prebuffering filter. */
8
9 #include <regex.h>
10 #include <stdbool.h>
11
12 #include "para.h"
13 #include "prebuffer_filter.cmdline.h"
14 #include "list.h"
15 #include "sched.h"
16 #include "ggo.h"
17 #include "buffer_tree.h"
18 #include "filter.h"
19 #include "string.h"
20 #include "error.h"
21
22 /** Data specific to the prebuffer filter. */
23 struct private_prebuffer_data {
24 /** The configuration data for this instance of the filter. */
25 struct prebuffer_filter_args_info *conf;
26 /** Number of bytes prebuffered or -1 if no longer prebuffering. */
27 int prebuffered;
28 /** End of prebuffering period. */
29 struct timeval barrier;
30 };
31
32 static ssize_t prebuffer_convert(char *inbuf, size_t inbuf_len,
33 struct filter_node *fn)
34 {
35 struct private_prebuffer_data *ppd = fn->private_data;
36 struct prebuffer_filter_args_info *conf = ppd->conf;
37
38 if (inbuf_len == 0) {
39 if (*fn->fc->input_error < 0 && ppd->prebuffered >= 0)
40 goto prebuffer_end;
41 return 0;
42 }
43 if (ppd->prebuffered < 0) {
44 size_t copy = PARA_MIN(inbuf_len, fn->bufsize - fn->loaded);
45 memcpy(fn->buf + fn->loaded, inbuf, copy);
46 fn->loaded += copy;
47 return copy;
48 }
49 if (ppd->prebuffered + inbuf_len > fn->bufsize) {
50 fn->bufsize = PARA_MAX(2 * fn->bufsize,
51 ppd->prebuffered + inbuf_len);
52 fn->buf = para_realloc(fn->buf, fn->bufsize);
53 }
54 memcpy(fn->buf + ppd->prebuffered, inbuf, inbuf_len);
55 if (ppd->prebuffered == 0) {
56 struct timeval tv;
57 PARA_INFO_LOG("prebuffer period %dms\n",
58 conf->duration_arg);
59 ms2tv(conf->duration_arg, &tv);
60 tv_add(&tv, now, &ppd->barrier);
61 }
62 ppd->prebuffered += inbuf_len;
63 PARA_DEBUG_LOG("%d bytes prebuffered\n", ppd->prebuffered);
64 if (*fn->fc->input_error >= 0) {
65 struct timeval diff;
66 if (tv_diff(now, &ppd->barrier, &diff) < 0)
67 goto out;
68 if (ppd->prebuffered < conf->size_arg)
69 goto out;
70 }
71 prebuffer_end:
72 fn->loaded = ppd->prebuffered;
73 ppd->prebuffered = -1;
74 out:
75 return inbuf_len;
76 }
77
78 static void prebuffer_pre_select(struct sched *s, struct task *t)
79 {
80 struct filter_node *fn = container_of(t, struct filter_node, task);
81 struct btr_node *btrn = fn->btrn;
82 size_t iqs = btr_get_input_queue_size(btrn);
83 struct private_prebuffer_data *ppd = fn->private_data;
84 struct prebuffer_filter_args_info *conf = ppd->conf;
85 struct timeval diff;
86
87 t->error = 0;
88 if (iqs == 0)
89 return;
90 if (ppd->barrier.tv_sec == 0) {
91 struct timeval tv;
92 PARA_INFO_LOG("prebuffer period %dms\n",
93 conf->duration_arg);
94 ms2tv(conf->duration_arg, &tv);
95 tv_add(&tv, now, &ppd->barrier);
96 }
97 if (tv_diff(&ppd->barrier, now, &diff) < 0)
98 goto min_delay;
99 if (tv_diff(&diff, &s->timeout, NULL) < 0)
100 s->timeout = diff;
101 return;
102 min_delay:
103 s->timeout.tv_sec = 0;
104 s->timeout.tv_usec = 1;
105 }
106
107 static void prebuffer_close(struct filter_node *fn)
108 {
109 free(fn->private_data);
110 free(fn->buf);
111 }
112
113 static void prebuffer_post_select(__a_unused struct sched *s, struct task *t)
114 {
115 struct filter_node *fn = container_of(t, struct filter_node, task);
116 struct btr_node *btrn = fn->btrn;
117 size_t iqs = btr_get_input_queue_size(btrn);
118 struct private_prebuffer_data *ppd = fn->private_data;
119 struct prebuffer_filter_args_info *conf = ppd->conf;
120
121 t->error = 0;
122 if (ppd->barrier.tv_sec == 0)
123 return;
124 if (tv_diff(now, &ppd->barrier, NULL) < 0)
125 return;
126 if (iqs < conf->size_arg)
127 return;
128 btr_splice_out_node(btrn);
129 prebuffer_close(fn);
130 t->error = -E_PREBUFFER_SUCCESS;
131 }
132
133 static int prebuffer_parse_config(int argc, char **argv, void **config)
134 {
135 struct prebuffer_filter_args_info *prebuffer_conf
136 = para_calloc(sizeof(*prebuffer_conf));
137 int ret = -E_PREBUFFER_SYNTAX;
138
139 if (prebuffer_cmdline_parser(argc, argv, prebuffer_conf))
140 goto err;
141 ret = -ERRNO_TO_PARA_ERROR(EINVAL);
142 if (prebuffer_conf->duration_arg < 0)
143 goto err;
144 if (prebuffer_conf->size_arg < 0)
145 goto err;
146 PARA_NOTICE_LOG("prebuffering %ims, %i bytes\n",
147 prebuffer_conf->duration_arg, prebuffer_conf->size_arg);
148 *config = prebuffer_conf;
149 return 1;
150 err:
151 free(prebuffer_conf);
152 return ret;
153 }
154
155 static void prebuffer_open(struct filter_node *fn)
156 {
157 struct private_prebuffer_data *ppd = para_calloc(sizeof(*ppd));
158
159 ppd->conf = fn->conf;
160 fn->private_data = ppd;
161 fn->bufsize = 8192; /* gets increased on demand */
162 fn->buf = para_malloc(fn->bufsize);
163 }
164
165 static void prebuffer_free_config(void *conf)
166 {
167 prebuffer_cmdline_parser_free(conf);
168 }
169
170 /**
171 * The init function of the prebuffer filter.
172 *
173 * \param f Pointer to the struct to initialize.
174 */
175 void prebuffer_filter_init(struct filter *f)
176 {
177 struct prebuffer_filter_args_info dummy;
178
179 prebuffer_cmdline_parser_init(&dummy);
180 f->open = prebuffer_open;
181 f->close = prebuffer_close;
182 f->convert = prebuffer_convert;
183 f->parse_config = prebuffer_parse_config;
184 f->free_config = prebuffer_free_config;
185 f->pre_select = prebuffer_pre_select;
186 f->post_select = prebuffer_post_select;
187 f->help = (struct ggo_help) {
188 .short_help = prebuffer_filter_args_info_help,
189 .detailed_help = prebuffer_filter_args_info_detailed_help
190 };
191 }