sideband.con commit DESTDIR support for git/contrib/emacs (1e31fbe)
   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 */
  14int recv_sideband(const char *me, int in_stream, int out, int err)
  15{
  16        char buf[7 + LARGE_PACKET_MAX + 1];
  17        strcpy(buf, "remote:");
  18        while (1) {
  19                int band, len;
  20                len     = packet_read_line(in_stream, buf+7, LARGE_PACKET_MAX);
  21                if (len == 0)
  22                        break;
  23                if (len < 1) {
  24                        len = sprintf(buf, "%s: protocol error: no band designator\n", me);
  25                        safe_write(err, buf, len);
  26                        return SIDEBAND_PROTOCOL_ERROR;
  27                }
  28                band = buf[7] & 0xff;
  29                len--;
  30                switch (band) {
  31                case 3:
  32                        buf[7] = ' ';
  33                        buf[8+len] = '\n';
  34                        safe_write(err, buf, 8+len+1);
  35                        return SIDEBAND_REMOTE_ERROR;
  36                case 2:
  37                        buf[7] = ' ';
  38                        safe_write(err, buf, 8+len);
  39                        continue;
  40                case 1:
  41                        safe_write(out, buf+8, len);
  42                        continue;
  43                default:
  44                        len = sprintf(buf,
  45                                      "%s: protocol error: bad band #%d\n",
  46                                      me, band);
  47                        safe_write(err, buf, len);
  48                        return SIDEBAND_PROTOCOL_ERROR;
  49                }
  50        }
  51        return 0;
  52}
  53
  54/*
  55 * fd is connected to the remote side; send the sideband data
  56 * over multiplexed packet stream.
  57 */
  58ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
  59{
  60        ssize_t ssz = sz;
  61        const char *p = data;
  62
  63        while (sz) {
  64                unsigned n;
  65                char hdr[5];
  66
  67                n = sz;
  68                if (packet_max - 5 < n)
  69                        n = packet_max - 5;
  70                sprintf(hdr, "%04x", n + 5);
  71                hdr[4] = band;
  72                safe_write(fd, hdr, 5);
  73                safe_write(fd, p, n);
  74                p += n;
  75                sz -= n;
  76        }
  77        return ssz;
  78}