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comparison tfo/tfo-trace-msg.c @ 29:fec87477e60b

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new program tfo-trace-msg
author Mychaela Falconia <falcon@freecalypso.org>
date Wed, 28 Aug 2024 02:28:37 +0000
parents
children 19039ffbe605
comparison
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28:9bcdb091c24d 29:fec87477e60b
1 /*
2 * This program reads a raw binary file that contains a recording of
3 * a T1/E1 timeslot on the MSC side of a TRAU, analyzes it looking for
4 * TFO IS messages, and prints whatever it finds.
5 */
6
7 #include <stdio.h>
8 #include <stdint.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <strings.h>
12
13 static uint8_t is_hunt_buf[320];
14 static int is_state;
15 static unsigned is_hunt_fill;
16 static unsigned is_offset;
17 static unsigned is_file_offset;
18 static unsigned is_bit_count;
19 static unsigned is_rx_word;
20
21 static const u_char hdr_pattern[20] = {0, 1, 0, 1, 0, 1, 1, 0, 1, 0,
22 0, 1, 1, 0, 1, 0, 1, 0, 0, 1};
23
24 static void
25 is_rx_hunt(cur_file_offset)
26 unsigned cur_file_offset;
27 {
28 unsigned offset, n;
29
30 for (offset = 0; offset < 16; offset++) {
31 for (n = 0; n < 20; n++)
32 if ((is_hunt_buf[offset + n*16] & 1) != hdr_pattern[n])
33 break;
34 if (n == 20)
35 break;
36 }
37 if (n != 20)
38 return;
39 is_offset = offset;
40 is_file_offset = cur_file_offset - 19*16 + offset;
41 is_state = 1;
42 is_bit_count = 0;
43 is_rx_word = 0;
44 is_hunt_fill = 0;
45 }
46
47 static void
48 is_process_cmd()
49 {
50 int cont;
51
52 printf("0x%x: ", is_file_offset);
53 switch (is_rx_word) {
54 case 0x05D:
55 printf("IS_REQ\n");
56 cont = 1;
57 break;
58 case 0x0BA:
59 printf("IS_ACK\n");
60 cont = 1;
61 break;
62 case 0x0E7:
63 printf("IS_IPE\n");
64 cont = 1;
65 break;
66 case 0x129:
67 printf("IS_FILL\n");
68 cont = 0;
69 break;
70 case 0x174:
71 printf("IS_DUP\n");
72 cont = 0;
73 break;
74 case 0x193:
75 printf("IS_SYL\n");
76 cont = 0;
77 break;
78 default:
79 printf("unknown IS_Command 0x%03X\n", is_rx_word);
80 cont = 0;
81 }
82 if (cont) {
83 is_state = 2;
84 is_bit_count = 0;
85 is_rx_word = 0;
86 } else
87 is_state = 0;
88 }
89
90 static void
91 is_process_ext()
92 {
93 printf(" IS_Extension: 0x%05X", is_rx_word);
94 if (is_rx_word & 0x80200) {
95 printf(" (bad sync)\n");
96 is_state = 0;
97 return;
98 }
99 switch (is_rx_word & 3) {
100 case 0:
101 printf(" (final)\n");
102 is_state = 0;
103 return;
104 case 3:
105 printf(" (continue)\n");
106 is_state = 2;
107 is_bit_count = 0;
108 is_rx_word = 0;
109 return;
110 default:
111 printf(" (bad EX)\n");
112 is_state = 0;
113 }
114 }
115
116 static void
117 is_rx_process(input, cur_file_offset)
118 uint8_t *input;
119 unsigned cur_file_offset;
120 {
121 unsigned new_bit;
122
123 memmove(is_hunt_buf, is_hunt_buf + 16, 304);
124 memcpy(is_hunt_buf + 304, input, 16);
125 if (!is_state) {
126 if (is_hunt_fill < 20)
127 is_hunt_fill++;
128 if (is_hunt_fill == 20)
129 is_rx_hunt(cur_file_offset);
130 return;
131 }
132 new_bit = input[is_offset] & 1;
133 is_rx_word <<= 1;
134 is_rx_word |= new_bit;
135 is_bit_count++;
136 if (is_state == 1 && is_bit_count == 10)
137 is_process_cmd();
138 else if (is_state == 2 && is_bit_count == 20)
139 is_process_ext();
140 }
141
142 main(argc, argv)
143 char **argv;
144 {
145 FILE *inf;
146 uint8_t chunk[16];
147 unsigned file_offset;
148 int cc;
149
150 if (argc != 2) {
151 fprintf(stderr, "usage: %s pcm-capture-file\n", argv[0]);
152 exit(1);
153 }
154 inf = fopen(argv[1], "r");
155 if (!inf) {
156 perror(argv[1]);
157 exit(1);
158 }
159 for (file_offset = 0; ; file_offset += 16) {
160 cc = fread(chunk, 1, 16, inf);
161 if (cc == 0)
162 break;
163 if (cc != 16) {
164 fprintf(stderr,
165 "error: read of 16 bytes returned %d\n", cc);
166 exit(1);
167 }
168 is_rx_process(chunk, file_offset);
169 }
170 exit(0);
171 }