FreeCalypso > hg > freecalypso-tools

annotate uptools/libcoding/gsm7_unpack.c @ 855:ea458ee48691

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
rvinterf/l1filter: new program written, compiles
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 09 Nov 2021 23:14:22 +0000
parents d29b45c4c8db
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
330
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 * This library module implements unpacking of GSM 7-bit data
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 * from packed octets.
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 */
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 #include <sys/types.h>
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 static u_char shift[8] = {0, 7, 6, 5, 4, 3, 2, 1};
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 gsm7_unpack(inbuf, outbuf, nseptets)
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 u_char *inbuf, *outbuf;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 unsigned nseptets;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 {
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14 u_char *inp = inbuf, *outp = outbuf;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 unsigned n;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 for (n = 0; n < nseptets; n++) {
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 *outp++ = (((inp[1] << 8) | inp[0]) >> shift[n&7]) & 0x7F;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19 if (n & 7)
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 inp++;
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21 }
d29b45c4c8db uptools/libcoding: 7-bit decoding implemented
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 }