ui/text_import_regex.c

   1 /* text_import_regex.c
   2  * Regex based text importer
   3  * March 2021, Paul Weiß <paulniklasweiss@gmail.com>
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * Based on text_import.c by Jaap Keuter <jaap.keuter@xs4all.nl>
  10  *
  11  * SPDX-License-Identifier: GPL-2.0-or-later
  12  */
  13
  14 #include "config.h"
  15
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18
  19 #include <glib.h>
  20
  21 #include "text_import.h"
  22 #include "text_import_regex.h"
  23
  24 typedef unsigned int uint;
  25
  26 /*--- Options --------------------------------------------------------------------*/
  27
  28 int text_import_regex(const text_import_info_t* info) {
  29     int status = 1;
  30     int parsed_packets = 0;
  31     ws_debug("starting import...");
  32
  33     // IO
  34     GMappedFile* file = g_mapped_file_ref(info->regex.import_text_GMappedFile);
  35     GError* gerror = NULL;
  36     size_t f_size = g_mapped_file_get_length(file);
  37     unsigned char* f_content = g_mapped_file_get_contents(file);
  38     { /* zero terminate the file */
  39         if (f_content[f_size -  1] != '\n') {
  40             fprintf(stderr, "Error: file did not end on \\n\n");
  41             g_mapped_file_unref(file);
  42             return -1;
  43         }
  44         f_content[f_size] = 0;
  45     }
  46
  47     // Regex result dissecting
  48     bool re_time, re_dir, re_seqno;
  49     GMatchInfo* match;
  50     int field_start;
  51     int field_end;
  52     { /* analyze regex */
  53         re_time = g_regex_get_string_number(info->regex.format, "time") >= 0;
  54         re_dir = g_regex_get_string_number(info->regex.format, "dir") >= 0;
  55         re_seqno = g_regex_get_string_number(info->regex.format, "seqno") >= 0;
  56         if (g_regex_get_string_number(info->regex.format, "data") < 0) {
  57             /* This should never happen, as the dialog checks for this */
  58             fprintf(stderr, "Error could not find data in pattern\n");
  59             g_mapped_file_unref(file);
  60             return -1;
  61         }
  62     }
  63
  64     ws_debug("regex has %s%s%s", re_dir ? "dir, " : "",
  65                                  re_time ? "time, " : "",
  66                                  re_seqno ? "seqno, " : "");
  67     g_regex_match(info->regex.format, f_content, G_REGEX_MATCH_NOTEMPTY, &match);
  68     while (g_match_info_matches(match)) {
  69         /* parse the data */
  70         if (!g_match_info_fetch_named_pos(match, "data", &field_start, &field_end)) {
  71             fprintf(stderr, "Warning: could not fetch data on would be packet %d, discarding\n", parsed_packets + 1);
  72             continue;
  73         }
  74         parse_data(f_content + field_start, f_content + field_end, info->regex.encoding);
  75
  76         /* parse the auxiliary information if present */
  77         if (re_time &&
  78                 g_match_info_fetch_named_pos(match, "time", &field_start, &field_end)) {
  79             parse_time(f_content + field_start, f_content + field_end, info->timestamp_format);
  80         } else {
  81             /* No time present, so add a fixed delta. */
  82             parse_time(NULL, NULL, NULL);
  83         }
  84
  85         if (re_dir &&
  86                 g_match_info_fetch_named_pos(match, "dir", &field_start, &field_end))
  87             parse_dir(f_content + field_start, f_content + field_end, info->regex.in_indication, info->regex.out_indication);
  88
  89         if (re_seqno &&
  90                 g_match_info_fetch_named_pos(match, "seqno", &field_start, &field_end))
  91             parse_seqno(f_content + field_start, f_content + field_end);
  92
  93         if (ws_log_get_level() == LOG_LEVEL_NOISY) {
  94             g_match_info_fetch_pos(match, 0, &field_start, &field_end);
  95             ws_noisy("Packet %d at %x to %x: %.*s\n", parsed_packets + 1,
  96                     field_start, field_end,
  97                     field_end - field_start, f_content + field_start);
  98         }
  99         flush_packet();
 100
 101
 102         /* prepare next packet */
 103         ++parsed_packets;
 104         g_match_info_next(match, &gerror);
 105         if (gerror && gerror->code) {
 106             status = -1;
 107             g_error_free(gerror);
 108             break;
 109         }
 110     }
 111     ws_debug("processed %d packets", parsed_packets);
 112     g_match_info_unref(match);
 113     g_mapped_file_unref(file);
 114     return status * parsed_packets;
 115 }