Merge git://git.bogomips.org/git-svn
[git/git.git] / sideband.c
CommitLineData
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JH
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 */
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NP
14
15#define PREFIX "remote:"
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JS
16
17#define ANSI_SUFFIX "\033[K"
18#define DUMB_SUFFIX " "
19
20#define FIX_SIZE 10 /* large enough for any of the above */
ebe8fa73 21
9ac13ec9 22int recv_sideband(const char *me, int in_stream, int out, int err)
49a52b1d 23{
ebe8fa73 24 unsigned pf = strlen(PREFIX);
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25 unsigned sf;
26 char buf[LARGE_PACKET_MAX + 2*FIX_SIZE];
27 char *suffix, *term;
6b9c42b4 28 int skip_pf = 0;
13e4760a 29
ebe8fa73 30 memcpy(buf, PREFIX, pf);
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31 term = getenv("TERM");
32 if (term && strcmp(term, "dumb"))
33 suffix = ANSI_SUFFIX;
34 else
35 suffix = DUMB_SUFFIX;
36 sf = strlen(suffix);
37
49a52b1d 38 while (1) {
9ac13ec9 39 int band, len;
ebe8fa73 40 len = packet_read_line(in_stream, buf + pf, LARGE_PACKET_MAX);
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JH
41 if (len == 0)
42 break;
43 if (len < 1) {
44 len = sprintf(buf, "%s: protocol error: no band designator\n", me);
45 safe_write(err, buf, len);
46 return SIDEBAND_PROTOCOL_ERROR;
47 }
ebe8fa73 48 band = buf[pf] & 0xff;
49a52b1d 49 len--;
9ac13ec9 50 switch (band) {
49a52b1d 51 case 3:
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NP
52 buf[pf] = ' ';
53 buf[pf+1+len] = '\n';
54 safe_write(err, buf, pf+1+len+1);
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JH
55 return SIDEBAND_REMOTE_ERROR;
56 case 2:
ebe8fa73 57 buf[pf] = ' ';
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NP
58 do {
59 char *b = buf;
60 int brk = 0;
ebe8fa73 61
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NP
62 /*
63 * If the last buffer didn't end with a line
64 * break then we should not print a prefix
65 * this time around.
66 */
67 if (skip_pf) {
68 b += pf+1;
69 } else {
70 len += pf+1;
71 brk += pf+1;
72 }
73
74 /* Look for a line break. */
75 for (;;) {
ed1902ef 76 brk++;
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NP
77 if (brk > len) {
78 brk = 0;
79 break;
80 }
81 if (b[brk-1] == '\n' ||
82 b[brk-1] == '\r')
ed1902ef
NP
83 break;
84 }
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NP
85
86 /*
87 * Let's insert a suffix to clear the end
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NP
88 * of the screen line if a line break was
89 * found. Also, if we don't skip the
90 * prefix, then a non-empty string must be
91 * present too.
ebe8fa73 92 */
6b9c42b4 93 if (brk > (skip_pf ? 0 : (pf+1 + 1))) {
13e4760a 94 char save[FIX_SIZE];
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NP
95 memcpy(save, b + brk, sf);
96 b[brk + sf - 1] = b[brk - 1];
97 memcpy(b + brk - 1, suffix, sf);
98 safe_write(err, b, brk + sf);
99 memcpy(b + brk, save, sf);
100 len -= brk;
101 } else {
102 int l = brk ? brk : len;
103 safe_write(err, b, l);
104 len -= l;
105 }
ebe8fa73 106
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107 skip_pf = !brk;
108 memmove(buf + pf+1, b + brk, len);
109 } while (len);
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110 continue;
111 case 1:
ebe8fa73 112 safe_write(out, buf + pf+1, len);
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113 continue;
114 default:
9ac13ec9 115 len = sprintf(buf,
49a52b1d 116 "%s: protocol error: bad band #%d\n",
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117 me, band);
118 safe_write(err, buf, len);
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119 return SIDEBAND_PROTOCOL_ERROR;
120 }
121 }
122 return 0;
123}
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JH
124
125/*
126 * fd is connected to the remote side; send the sideband data
127 * over multiplexed packet stream.
128 */
129ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
130{
131 ssize_t ssz = sz;
132 const char *p = data;
133
134 while (sz) {
135 unsigned n;
136 char hdr[5];
137
138 n = sz;
139 if (packet_max - 5 < n)
140 n = packet_max - 5;
141 sprintf(hdr, "%04x", n + 5);
142 hdr[4] = band;
143 safe_write(fd, hdr, 5);
144 safe_write(fd, p, n);
145 p += n;
146 sz -= n;
147 }
148 return ssz;
149}