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 }