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
   7 /** \file filter.c The stand-alone filter program. */
   8
   9 #include "para.h"
  10
  11 #include "filter.cmdline.h"
  12 #include "list.h"
  13 #include "sched.h"
  14 #include "filter.h"
  15 #include "string.h"
  16 #include "stdin.h"
  17 #include "stdout.h"
  18 #include "error.h"
  19
  20 char *stat_item_values[NUM_STAT_ITEMS] = {NULL};
  21
  22 /** Initialize the array of errors for para_filter. */
  23 INIT_FILTER_ERRLISTS;
  24
  25 /** The task that reads from stdin. */
  26 static struct stdin_task stdin_task_struct;
  27 /** pointer to the stdin task. */
  28 static struct stdin_task *sit = &stdin_task_struct;
  29
  30 /** The task that filters the data. */
  31 static struct filter_chain filter_chain_struct;
  32 /** Pointer to the filter chain. */
  33 static struct filter_chain *fc = &filter_chain_struct;
  34
  35 /** The task that writes converted data to stdout. */
  36 static struct stdout_task stdout_task_struct;
  37 /** Pointer to the stdout task. */
  38 static struct stdout_task *sot = &stdout_task_struct;
  39
  40 /** Gengetopt struct that holds the command line args. */
  41 static struct filter_args_info conf;
  42
  43 INIT_STDERR_LOGGING(conf.loglevel_arg);
  44
  45 static void open_filters(void)
  46 {
  47         int i;
  48         struct filter_node *fn;
  49
  50         FOR_EACH_FILTER_NODE(fn, fc, i) {
  51                 struct filter *f = filters + fn->filter_num;
  52                 f->open(fn);
  53                 PARA_INFO_LOG("opened %s filter\n", f->name);
  54                 fc->outbuf = fn->buf;
  55                 fc->out_loaded = &fn->loaded;
  56         }
  57 }
  58
  59 static int init_filter_chain(void)
  60 {
  61         int i, ret;
  62         struct filter_node *fn;
  63
  64         if (!conf.filter_given)
  65                 return -E_NO_FILTERS;
  66         fc->num_filters = conf.filter_given;
  67         fc->filter_nodes = para_malloc(fc->num_filters * sizeof(struct filter_node));
  68         fc->inbuf = sit->buf;
  69         fc->in_loaded = &sit->loaded;
  70         fc->input_error = &sit->task.error;
  71         fc->task.error = 0;
  72         fc->output_error = &sot->task.error;
  73         fc->task.pre_select = filter_pre_select;
  74         sprintf(fc->task.status, "filter chain");
  75
  76         FOR_EACH_FILTER_NODE(fn, fc, i) {
  77                 char *fa = conf.filter_arg[i];
  78                 fn = fc->filter_nodes + i;
  79                 ret = check_filter_arg(fa, &fn->conf);
  80                 if (ret < 0)
  81                         goto err;
  82                 fn->filter_num = ret;
  83                 fn->fc = fc;
  84                 INIT_LIST_HEAD(&fn->callbacks);
  85                 PARA_DEBUG_LOG("filter #%d: %s\n", i, filters[fn->filter_num].name);
  86         }
  87         open_filters();
  88         return 1;
  89 err:
  90         free(fc->filter_nodes);
  91         return ret;
  92 }
  93
  94 static int parse_config(int argc, char *argv[])
  95 {
  96         static char *cf; /* config file */
  97         struct stat statbuf;
  98         int i;
  99
 100         if (filter_cmdline_parser(argc, argv, &conf))
 101                 return -E_FILTER_SYNTAX;
 102         HANDLE_VERSION_FLAG("filter", conf);
 103         if (!cf) {
 104                 char *home = para_homedir();
 105                 cf = make_message("%s/.paraslash/filter.conf", home);
 106                 free(home);
 107         }
 108         if (!stat(cf, &statbuf)) {
 109                 struct filter_cmdline_parser_params params = {
 110                         .override = 0,
 111                         .initialize = 0,
 112                         .check_required = 0,
 113                         .check_ambiguity = 0
 114                 };
 115                 if (filter_cmdline_parser_config_file(cf, &conf, &params))
 116                         return -E_FILTER_SYNTAX;
 117         }
 118         if (!conf.list_filters_given)
 119                 return 1;
 120         printf("available filters: ");
 121         for (i = 0; filters[i].name; i++)
 122                 printf("%s%s%s", i? " " : "", filters[i].name,
 123                         filters[i].parse_config? "*": "");
 124         printf("\nFilters marked with \"*\" have further command line options. Try\n"
 125                 "\tpara_filter -f '<filtername> -h'\nfor more information.\n");
 126         exit(EXIT_SUCCESS);
 127 }
 128
 129 /**
 130  * The main function of para_filter.
 131  *
 132  * Para_filter reads data from stdin, converts it by using a chain
 133  * of filters (specified on the command line) and writes the resulting
 134  * data to stdout.
 135  *
 136  * \param argc Number of command line options.
 137  * \param argv Vector of arguments.
 138  *
 139  * \return \a EXIT_SUCCESS on success, EXIT_FAILURE on errors.
 140  */
 141 int main(int argc, char *argv[])
 142 {
 143         int ret;
 144         static struct sched s;
 145
 146         stdin_set_defaults(sit);
 147         sit->buf = para_malloc(sit->bufsize),
 148
 149         filter_init(filters);
 150         ret = parse_config(argc, argv);
 151         if (ret < 0)
 152                 goto out;
 153         ret = init_filter_chain();
 154         if (ret < 0)
 155                 goto out;
 156
 157         stdout_set_defaults(sot);
 158         sot->buf = fc->outbuf;
 159         sot->loaded = fc->out_loaded;
 160         sot->input_error = &fc->task.error;
 161
 162         register_task(&sit->task);
 163         register_task(&fc->task);
 164         register_task(&sot->task);
 165         s.default_timeout.tv_sec = 1;
 166         s.default_timeout.tv_usec = 0;
 167         ret = schedule(&s);
 168         close_filters(fc);
 169 out:
 170         free(sit->buf);
 171         if (ret < 0)
 172                 PARA_EMERG_LOG("%s\n", para_strerror(-ret));
 173         return ret < 0? EXIT_FAILURE : EXIT_SUCCESS;
 174 }