git/sideband.c

152 строки
3.4 KiB
C

#include "pkt-line.h"
#include "sideband.h"
/*
* Receive multiplexed output stream over git native protocol.
* in_stream is the input stream from the remote, which carries data
* in pkt_line format with band designator. Demultiplex it into out
* and err and return error appropriately. Band #1 carries the
* primary payload. Things coming over band #2 is not necessarily
* error; they are usually informative message on the standard error
* stream, aka "verbose"). A message over band #3 is a signal that
* the remote died unexpectedly. A flush() concludes the stream.
*/
#define PREFIX "remote:"
#define ANSI_SUFFIX "\033[K"
#define DUMB_SUFFIX " "
#define FIX_SIZE 10 /* large enough for any of the above */
int recv_sideband(const char *me, int in_stream, int out)
{
unsigned pf = strlen(PREFIX);
unsigned sf;
char buf[LARGE_PACKET_MAX + 2*FIX_SIZE];
char *suffix, *term;
int skip_pf = 0;
memcpy(buf, PREFIX, pf);
term = getenv("TERM");
if (term && strcmp(term, "dumb"))
suffix = ANSI_SUFFIX;
else
suffix = DUMB_SUFFIX;
sf = strlen(suffix);
while (1) {
int band, len;
len = packet_read_line(in_stream, buf + pf, LARGE_PACKET_MAX);
if (len == 0)
break;
if (len < 1) {
fprintf(stderr, "%s: protocol error: no band designator\n", me);
return SIDEBAND_PROTOCOL_ERROR;
}
band = buf[pf] & 0xff;
len--;
switch (band) {
case 3:
buf[pf] = ' ';
buf[pf+1+len] = '\0';
fprintf(stderr, "%s\n", buf);
return SIDEBAND_REMOTE_ERROR;
case 2:
buf[pf] = ' ';
do {
char *b = buf;
int brk = 0;
/*
* If the last buffer didn't end with a line
* break then we should not print a prefix
* this time around.
*/
if (skip_pf) {
b += pf+1;
} else {
len += pf+1;
brk += pf+1;
}
/* Look for a line break. */
for (;;) {
brk++;
if (brk > len) {
brk = 0;
break;
}
if (b[brk-1] == '\n' ||
b[brk-1] == '\r')
break;
}
/*
* Let's insert a suffix to clear the end
* of the screen line if a line break was
* found. Also, if we don't skip the
* prefix, then a non-empty string must be
* present too.
*/
if (brk > (skip_pf ? 0 : (pf+1 + 1))) {
char save[FIX_SIZE];
memcpy(save, b + brk, sf);
b[brk + sf - 1] = b[brk - 1];
memcpy(b + brk - 1, suffix, sf);
fprintf(stderr, "%.*s", brk + sf, b);
memcpy(b + brk, save, sf);
len -= brk;
} else {
int l = brk ? brk : len;
fprintf(stderr, "%.*s", l, b);
len -= l;
}
skip_pf = !brk;
memmove(buf + pf+1, b + brk, len);
} while (len);
continue;
case 1:
safe_write(out, buf + pf+1, len);
continue;
default:
fprintf(stderr, "%s: protocol error: bad band #%d\n",
me, band);
return SIDEBAND_PROTOCOL_ERROR;
}
}
return 0;
}
/*
* fd is connected to the remote side; send the sideband data
* over multiplexed packet stream.
*/
ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
{
ssize_t ssz = sz;
const char *p = data;
while (sz) {
unsigned n;
char hdr[5];
n = sz;
if (packet_max - 5 < n)
n = packet_max - 5;
if (0 <= band) {
sprintf(hdr, "%04x", n + 5);
hdr[4] = band;
safe_write(fd, hdr, 5);
} else {
sprintf(hdr, "%04x", n + 4);
safe_write(fd, hdr, 4);
}
safe_write(fd, p, n);
p += n;
sz -= n;
}
return ssz;
}