Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "pkt-line.h"
   3#include "sideband.h"
   4
   5/*
   6 * Receive multiplexed output stream over git native protocol.
   7 * in_stream is the input stream from the remote, which carries data
   8 * in pkt_line format with band designator.  Demultiplex it into out
   9 * and err and return error appropriately.  Band #1 carries the
  10 * primary payload.  Things coming over band #2 is not necessarily
  11 * error; they are usually informative message on the standard error
  12 * stream, aka "verbose").  A message over band #3 is a signal that
  13 * the remote died unexpectedly.  A flush() concludes the stream.
  14 */
  15
  16#define PREFIX "remote:"
  17
  18#define ANSI_SUFFIX "\033[K"
  19#define DUMB_SUFFIX "        "
  20
  21#define FIX_SIZE 10  /* large enough for any of the above */
  22
  23int recv_sideband(const char *me, int in_stream, int out)
  24{
  25        unsigned pf = strlen(PREFIX);
  26        unsigned sf;
  27        char buf[LARGE_PACKET_MAX + 2*FIX_SIZE];
  28        char *suffix, *term;
  29        int skip_pf = 0;
  30
  31        memcpy(buf, PREFIX, pf);
  32        term = getenv("TERM");
  33        if (isatty(2) && term && strcmp(term, "dumb"))
  34                suffix = ANSI_SUFFIX;
  35        else
  36                suffix = DUMB_SUFFIX;
  37        sf = strlen(suffix);
  38
  39        while (1) {
  40                int band, len;
  41                len = packet_read(in_stream, NULL, NULL, buf + pf, LARGE_PACKET_MAX, 0);
  42                if (len == 0)
  43                        break;
  44                if (len < 1) {
  45                        fprintf(stderr, "%s: protocol error: no band designator\n", me);
  46                        return SIDEBAND_PROTOCOL_ERROR;
  47                }
  48                band = buf[pf] & 0xff;
  49                len--;
  50                switch (band) {
  51                case 3:
  52                        buf[pf] = ' ';
  53                        buf[pf+1+len] = '\0';
  54                        fprintf(stderr, "%s\n", buf);
  55                        return SIDEBAND_REMOTE_ERROR;
  56                case 2:
  57                        buf[pf] = ' ';
  58                        do {
  59                                char *b = buf;
  60                                int brk = 0;
  61
  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 (;;) {
  76                                        brk++;
  77                                        if (brk > len) {
  78                                                brk = 0;
  79                                                break;
  80                                        }
  81                                        if (b[brk-1] == '\n' ||
  82                                            b[brk-1] == '\r')
  83                                                break;
  84                                }
  85
  86                                /*
  87                                 * Let's insert a suffix to clear the end
  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.
  92                                 */
  93                                if (brk > (skip_pf ? 0 : (pf+1 + 1))) {
  94                                        char save[FIX_SIZE];
  95                                        memcpy(save, b + brk, sf);
  96                                        b[brk + sf - 1] = b[brk - 1];
  97                                        memcpy(b + brk - 1, suffix, sf);
  98                                        fprintf(stderr, "%.*s", brk + sf, b);
  99                                        memcpy(b + brk, save, sf);
 100                                        len -= brk;
 101                                } else {
 102                                        int l = brk ? brk : len;
 103                                        fprintf(stderr, "%.*s", l, b);
 104                                        len -= l;
 105                                }
 106
 107                                skip_pf = !brk;
 108                                memmove(buf + pf+1, b + brk, len);
 109                        } while (len);
 110                        continue;
 111                case 1:
 112                        write_or_die(out, buf + pf+1, len);
 113                        continue;
 114                default:
 115                        fprintf(stderr, "%s: protocol error: bad band #%d\n",
 116                                me, band);
 117                        return SIDEBAND_PROTOCOL_ERROR;
 118                }
 119        }
 120        return 0;
 121}
 122
 123/*
 124 * fd is connected to the remote side; send the sideband data
 125 * over multiplexed packet stream.
 126 */
 127void send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max)
 128{
 129        const char *p = data;
 130
 131        while (sz) {
 132                unsigned n;
 133                char hdr[5];
 134
 135                n = sz;
 136                if (packet_max - 5 < n)
 137                        n = packet_max - 5;
 138                if (0 <= band) {
 139                        xsnprintf(hdr, sizeof(hdr), "%04x", n + 5);
 140                        hdr[4] = band;
 141                        write_or_die(fd, hdr, 5);
 142                } else {
 143                        xsnprintf(hdr, sizeof(hdr), "%04x", n + 4);
 144                        write_or_die(fd, hdr, 4);
 145                }
 146                write_or_die(fd, p, n);
 147                p += n;
 148                sz -= n;
 149        }
 150}