Move sideband client side support into reusable form.
[git/git.git] / sideband.c
1 #include "pkt-line.h"
2 #include "sideband.h"
3
4 /*
5 * Receive multiplexed output stream over git native protocol.
6 * in_stream is the input stream from the remote, which carries data
7 * in pkt_line format with band designator. Demultiplex it into out
8 * and err and return error appropriately. Band #1 carries the
9 * primary payload. Things coming over band #2 is not necessarily
10 * error; they are usually informative message on the standard error
11 * stream, aka "verbose"). A message over band #3 is a signal that
12 * the remote died unexpectedly. A flush() concludes the stream.
13 */
14 int recv_sideband(const char *me, int in_stream, int out, int err, char *buf, int bufsz)
15 {
16 while (1) {
17 int len = packet_read_line(in_stream, buf, bufsz);
18 if (len == 0)
19 break;
20 if (len < 1) {
21 len = sprintf(buf, "%s: protocol error: no band designator\n", me);
22 safe_write(err, buf, len);
23 return SIDEBAND_PROTOCOL_ERROR;
24 }
25 len--;
26 switch (buf[0] & 0xFF) {
27 case 3:
28 safe_write(err, "remote: ", 8);
29 safe_write(err, buf+1, len);
30 safe_write(err, "\n", 1);
31 return SIDEBAND_REMOTE_ERROR;
32 case 2:
33 safe_write(err, "remote: ", 8);
34 safe_write(err, buf+1, len);
35 continue;
36 case 1:
37 safe_write(out, buf+1, len);
38 continue;
39 default:
40 len = sprintf(buf + 1,
41 "%s: protocol error: bad band #%d\n",
42 me, buf[0] & 0xFF);
43 safe_write(err, buf+1, len);
44 return SIDEBAND_PROTOCOL_ERROR;
45 }
46 }
47 return 0;
48 }