Andrew's git - gitweb.git/blob

   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                        len += 8;
  39                        while (1) {
  40                                int brk = 8;
  41                                while (brk < len) {
  42                                        brk++;
  43                                        if (buf[brk-1] == '\n' ||
  44                                            buf[brk-1] == '\r')
  45                                                break;
  46                                }
  47                                safe_write(err, buf, brk);
  48                                if (brk < len) {
  49                                        memmove(buf + 8, buf + brk, len - brk);
  50                                        len = len - brk + 8;
  51                                } else
  52                                        break;
  53                        }
  54                        continue;
  55                case 1:
  56                        safe_write(out, buf+8, len);
  57                        continue;
  58                default:
  59                        len = sprintf(buf,
  60                                      "%s: protocol error: bad band #%d\n",
  61                                      me, band);
  62                        safe_write(err, buf, len);
  63                        return SIDEBAND_PROTOCOL_ERROR;
  64                }
  65        }
  66        return 0;
  67}
  68
  69/*
  70 * fd is connected to the remote side; send the sideband data
  71 * over multiplexed packet stream.
  72 */
  73ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
  74{
  75        ssize_t ssz = sz;
  76        const char *p = data;
  77
  78        while (sz) {
  79                unsigned n;
  80                char hdr[5];
  81
  82                n = sz;
  83                if (packet_max - 5 < n)
  84                        n = packet_max - 5;
  85                sprintf(hdr, "%04x", n + 5);
  86                hdr[4] = band;
  87                safe_write(fd, hdr, 5);
  88                safe_write(fd, p, n);
  89                p += n;
  90                sz -= n;
  91        }
  92        return ssz;
  93}