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 */
  14
  15#define PREFIX "remote:"
  16
  17#define ANSI_SUFFIX "\033[K"
  18#define DUMB_SUFFIX "        "
  19
  20#define FIX_SIZE 10  /* large enough for any of the above */
  21
  22int recv_sideband(const char *me, int in_stream, int out, int err)
  23{
  24        unsigned pf = strlen(PREFIX);
  25        unsigned sf;
  26        char buf[LARGE_PACKET_MAX + 2*FIX_SIZE];
  27        char *suffix, *term;
  28
  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);
  36
  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;
  46                }
  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;
  60
  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;
  67                                }
  68
  69                                /*
  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.
  73                                 */
  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);
  83
  84                                if (brk < len) {
  85                                        memmove(buf + pf+1, buf + brk, len - brk);
  86                                        len = len - brk + pf+1;
  87                                } else
  88                                        break;
  89                        }
  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;
 100                }
 101        }
 102        return 0;
 103}
 104
 105/*
 106 * fd is connected to the remote side; send the sideband data
 107 * over multiplexed packet stream.
 108 */
 109ssize_t send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
 110{
 111        ssize_t ssz = sz;
 112        const char *p = data;
 113
 114        while (sz) {
 115                unsigned n;
 116                char hdr[5];
 117
 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;
 127        }
 128        return ssz;
 129}