annotate libutil/gsm7_unpack.c @ 179:efe944a5c4e3

doc/Brute-force-search: update for data directory rename
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 02 Mar 2021 05:20:19 +0000
parents f064dbcc5f41
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
50
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 * This library module implements unpacking of GSM 7-bit data
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 * from packed octets.
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 */
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 #include <sys/types.h>
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 static u_char shift[8] = {0, 7, 6, 5, 4, 3, 2, 1};
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 gsm7_unpack(inbuf, outbuf, nseptets)
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 u_char *inbuf, *outbuf;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 unsigned nseptets;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 {
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 u_char *inp = inbuf, *outp = outbuf;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 unsigned n;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 for (n = 0; n < nseptets; n++) {
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 *outp++ = (((inp[1] << 8) | inp[0]) >> shift[n&7]) & 0x7F;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 if (n & 7)
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 inp++;
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 }
dc8a2e6fa03e fc-simtool pnn-dump implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 }