gitweb: use new Git::Repo API, and add optional caching
[git/gitweb-caching.git] / sideband.c
blobb6777812cb92c1c169ee395164d53a0c2e6eceb2
1 #include "pkt-line.h"
2 #include "sideband.h"
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.
15 #define PREFIX "remote:"
17 #define ANSI_SUFFIX "\033[K"
18 #define DUMB_SUFFIX " "
20 #define FIX_SIZE 10 /* large enough for any of the above */
22 int recv_sideband(const char *me, int in_stream, int out, int err)
24 unsigned pf = strlen(PREFIX);
25 unsigned sf;
26 char buf[LARGE_PACKET_MAX + 2*FIX_SIZE];
27 char *suffix, *term;
29 memcpy(buf, PREFIX, pf);
30 term = getenv("TERM");
31 if (term && strcmp(term, "dumb"))
32 suffix = ANSI_SUFFIX;
33 else
34 suffix = DUMB_SUFFIX;
35 sf = strlen(suffix);
37 while (1) {
38 int band, len;
39 len = packet_read_line(in_stream, buf + pf, LARGE_PACKET_MAX);
40 if (len == 0)
41 break;
42 if (len < 1) {
43 len = sprintf(buf, "%s: protocol error: no band designator\n", me);
44 safe_write(err, buf, len);
45 return SIDEBAND_PROTOCOL_ERROR;
47 band = buf[pf] & 0xff;
48 len--;
49 switch (band) {
50 case 3:
51 buf[pf] = ' ';
52 buf[pf+1+len] = '\n';
53 safe_write(err, buf, pf+1+len+1);
54 return SIDEBAND_REMOTE_ERROR;
55 case 2:
56 buf[pf] = ' ';
57 len += pf+1;
58 while (1) {
59 int brk = pf+1;
61 /* Break the buffer into separate lines. */
62 while (brk < len) {
63 brk++;
64 if (buf[brk-1] == '\n' ||
65 buf[brk-1] == '\r')
66 break;
70 * Let's insert a suffix to clear the end
71 * of the screen line, but only if current
72 * line data actually contains something.
74 if (brk > pf+1 + 1) {
75 char save[FIX_SIZE];
76 memcpy(save, buf + brk, sf);
77 buf[brk + sf - 1] = buf[brk - 1];
78 memcpy(buf + brk - 1, suffix, sf);
79 safe_write(err, buf, brk + sf);
80 memcpy(buf + brk, save, sf);
81 } else
82 safe_write(err, buf, brk);
84 if (brk < len) {
85 memmove(buf + pf+1, buf + brk, len - brk);
86 len = len - brk + pf+1;
87 } else
88 break;
90 continue;
91 case 1:
92 safe_write(out, buf + pf+1, len);
93 continue;
94 default:
95 len = sprintf(buf,
96 "%s: protocol error: bad band #%d\n",
97 me, band);
98 safe_write(err, buf, len);
99 return SIDEBAND_PROTOCOL_ERROR;
102 return 0;
106 * fd is connected to the remote side; send the sideband data
107 * over multiplexed packet stream.
109 ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
111 ssize_t ssz = sz;
112 const char *p = data;
114 while (sz) {
115 unsigned n;
116 char hdr[5];
118 n = sz;
119 if (packet_max - 5 < n)
120 n = packet_max - 5;
121 sprintf(hdr, "%04x", n + 5);
122 hdr[4] = band;
123 safe_write(fd, hdr, 5);
124 safe_write(fd, p, n);
125 p += n;
126 sz -= n;
128 return ssz;