afs.c: Get rid of unregister_tasks().
[paraslash.git] / filter.c
1 /*
2 * Copyright (C) 2005-2008 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6 /** \file filter.c the stand-alone filter program */
7
8 #include "para.h"
9
10 #include "filter.cmdline.h"
11 #include "list.h"
12 #include "sched.h"
13 #include "filter.h"
14 #include "string.h"
15 #include "stdin.h"
16 #include "stdout.h"
17 #include "error.h"
18
19 /** init the array of errors for para_filter */
20 INIT_FILTER_ERRLISTS;
21
22 /** the task that reads from stdin */
23 static struct stdin_task stdin_task_struct;
24 /** pointer to the stdin task */
25 static struct stdin_task *sit = &stdin_task_struct;
26
27 /** the task that filters the data */
28 static struct filter_chain filter_chain_struct;
29 /** pointer to the filter chain */
30 static struct filter_chain *fc = &filter_chain_struct;
31
32 /** the task that writes converted data to stdout */
33 static struct stdout_task stdout_task_struct;
34 /** pointer to the stdout task */
35 static struct stdout_task *sot = &stdout_task_struct;
36
37 /** gengetopt struct that holds the command line args */
38 static struct filter_args_info conf;
39
40 INIT_STDERR_LOGGING(conf.loglevel_arg);
41
42 static void open_filters(void)
43 {
44 struct filter_node *fn;
45
46 list_for_each_entry(fn, &fc->filters, node) {
47 fn->filter->open(fn);
48 PARA_INFO_LOG("opened %s filter\n", fn->filter->name);
49 fc->outbuf = fn->buf;
50 fc->out_loaded = &fn->loaded;
51 }
52 }
53
54 static int init_filter_chain(void)
55 {
56 int i, filter_num;
57 struct filter_node *fn;
58
59 INIT_LIST_HEAD(&fc->filters);
60
61 fc->inbuf = sit->buf;
62 fc->in_loaded = &sit->loaded;
63 fc->input_error = &sit->task.error;
64 fc->task.error = 0;
65 fc->output_error = &sot->task.error;
66 fc->task.pre_select = filter_pre_select;
67 sprintf(fc->task.status, "filter chain");
68
69 for (i = 0; i < conf.filter_given; i++) {
70 char *fa = conf.filter_arg[i];
71 fn = para_calloc(sizeof(struct filter_node));
72 filter_num = check_filter_arg(fa, &fn->conf);
73 if (filter_num < 0) {
74 free(fn);
75 return filter_num;
76 }
77 fn->fc = fc;
78 INIT_LIST_HEAD(&fn->callbacks);
79 fn->filter = &filters[filter_num];
80 PARA_DEBUG_LOG("adding %s to filter chain\n", fn->filter->name);
81 list_add_tail(&fn->node, &fc->filters);
82 }
83 if (list_empty(&fc->filters))
84 return -E_NO_FILTERS;
85 open_filters();
86 return 1;
87 }
88
89 static int parse_config(int argc, char *argv[])
90 {
91 static char *cf; /* config file */
92 struct stat statbuf;
93 int i;
94
95 if (filter_cmdline_parser(argc, argv, &conf))
96 return -E_FILTER_SYNTAX;
97 HANDLE_VERSION_FLAG("filter", conf);
98 if (!cf) {
99 char *home = para_homedir();
100 cf = make_message("%s/.paraslash/filter.conf", home);
101 free(home);
102 }
103 if (!stat(cf, &statbuf)) {
104 struct filter_cmdline_parser_params params = {
105 .override = 0,
106 .initialize = 0,
107 .check_required = 0,
108 .check_ambiguity = 0
109 };
110 if (filter_cmdline_parser_config_file(cf, &conf, &params))
111 return -E_FILTER_SYNTAX;
112 }
113 if (!conf.list_filters_given)
114 return 1;
115 printf("available filters: ");
116 for (i = 0; filters[i].name; i++)
117 printf("%s%s%s", i? " " : "", filters[i].name,
118 filters[i].parse_config? "*": "");
119 printf("\nFilters marked with \"*\" have further command line options. Try\n"
120 "\tpara_filter -f '<filtername> -h'\nfor more information.\n");
121 exit(EXIT_SUCCESS);
122 }
123
124 /**
125 * para_filter's main function.
126 *
127 * para_filter reads data from stdin, converts it by using a chain
128 * of filters (specified on the command line) and writes the resulting
129 * data to stdout.
130 *
131 * \param argc number of command line options
132 * \param argv vector of arguments
133 *
134 * \return \a EXIT_SUCCESS on success, EXIT_FAILURE on errors.
135 */
136 int main(int argc, char *argv[])
137 {
138 int ret;
139 struct sched s;
140
141 stdin_set_defaults(sit);
142 sit->buf = para_malloc(sit->bufsize),
143
144 filter_init(filters);
145 ret = parse_config(argc, argv);
146 if (ret < 0)
147 goto out;
148 ret = init_filter_chain();
149 if (ret < 0)
150 goto out;
151
152 stdout_set_defaults(sot);
153 sot->buf = fc->outbuf;
154 sot->loaded = fc->out_loaded;
155 sot->input_error = &fc->task.error;
156
157 register_task(&sit->task);
158 register_task(&fc->task);
159 register_task(&sot->task);
160 s.default_timeout.tv_sec = 1;
161 s.default_timeout.tv_usec = 0;
162 ret = schedule(&s);
163 out:
164 free(sit->buf);
165 close_filters(fc);
166 if (ret < 0)
167 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
168 return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
169 }