Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "pkt-line.h"
   3#include "run-command.h"
   4
   5char packet_buffer[LARGE_PACKET_MAX];
   6static const char *packet_trace_prefix = "git";
   7static struct trace_key trace_packet = TRACE_KEY_INIT(PACKET);
   8static struct trace_key trace_pack = TRACE_KEY_INIT(PACKFILE);
   9
  10void packet_trace_identity(const char *prog)
  11{
  12        packet_trace_prefix = xstrdup(prog);
  13}
  14
  15static const char *get_trace_prefix(void)
  16{
  17        return in_async() ? "sideband" : packet_trace_prefix;
  18}
  19
  20static int packet_trace_pack(const char *buf, unsigned int len, int sideband)
  21{
  22        if (!sideband) {
  23                trace_verbatim(&trace_pack, buf, len);
  24                return 1;
  25        } else if (len && *buf == '\1') {
  26                trace_verbatim(&trace_pack, buf + 1, len - 1);
  27                return 1;
  28        } else {
  29                /* it's another non-pack sideband */
  30                return 0;
  31        }
  32}
  33
  34static void packet_trace(const char *buf, unsigned int len, int write)
  35{
  36        int i;
  37        struct strbuf out;
  38        static int in_pack, sideband;
  39
  40        if (!trace_want(&trace_packet) && !trace_want(&trace_pack))
  41                return;
  42
  43        if (in_pack) {
  44                if (packet_trace_pack(buf, len, sideband))
  45                        return;
  46        } else if (starts_with(buf, "PACK") || starts_with(buf, "\1PACK")) {
  47                in_pack = 1;
  48                sideband = *buf == '\1';
  49                packet_trace_pack(buf, len, sideband);
  50
  51                /*
  52                 * Make a note in the human-readable trace that the pack data
  53                 * started.
  54                 */
  55                buf = "PACK ...";
  56                len = strlen(buf);
  57        }
  58
  59        if (!trace_want(&trace_packet))
  60                return;
  61
  62        /* +32 is just a guess for header + quoting */
  63        strbuf_init(&out, len+32);
  64
  65        strbuf_addf(&out, "packet: %12s%c ",
  66                    get_trace_prefix(), write ? '>' : '<');
  67
  68        /* XXX we should really handle printable utf8 */
  69        for (i = 0; i < len; i++) {
  70                /* suppress newlines */
  71                if (buf[i] == '\n')
  72                        continue;
  73                if (buf[i] >= 0x20 && buf[i] <= 0x7e)
  74                        strbuf_addch(&out, buf[i]);
  75                else
  76                        strbuf_addf(&out, "\\%o", buf[i]);
  77        }
  78
  79        strbuf_addch(&out, '\n');
  80        trace_strbuf(&trace_packet, &out);
  81        strbuf_release(&out);
  82}
  83
  84/*
  85 * If we buffered things up above (we don't, but we should),
  86 * we'd flush it here
  87 */
  88void packet_flush(int fd)
  89{
  90        packet_trace("0000", 4, 1);
  91        write_or_die(fd, "0000", 4);
  92}
  93
  94void packet_buf_flush(struct strbuf *buf)
  95{
  96        packet_trace("0000", 4, 1);
  97        strbuf_add(buf, "0000", 4);
  98}
  99
 100#define hex(a) (hexchar[(a) & 15])
 101static void format_packet(struct strbuf *out, const char *fmt, va_list args)
 102{
 103        static char hexchar[] = "0123456789abcdef";
 104        size_t orig_len, n;
 105
 106        orig_len = out->len;
 107        strbuf_addstr(out, "0000");
 108        strbuf_vaddf(out, fmt, args);
 109        n = out->len - orig_len;
 110
 111        if (n > LARGE_PACKET_MAX)
 112                die("protocol error: impossibly long line");
 113
 114        out->buf[orig_len + 0] = hex(n >> 12);
 115        out->buf[orig_len + 1] = hex(n >> 8);
 116        out->buf[orig_len + 2] = hex(n >> 4);
 117        out->buf[orig_len + 3] = hex(n);
 118        packet_trace(out->buf + orig_len + 4, n - 4, 1);
 119}
 120
 121void packet_write(int fd, const char *fmt, ...)
 122{
 123        static struct strbuf buf = STRBUF_INIT;
 124        va_list args;
 125
 126        strbuf_reset(&buf);
 127        va_start(args, fmt);
 128        format_packet(&buf, fmt, args);
 129        va_end(args);
 130        write_or_die(fd, buf.buf, buf.len);
 131}
 132
 133void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
 134{
 135        va_list args;
 136
 137        va_start(args, fmt);
 138        format_packet(buf, fmt, args);
 139        va_end(args);
 140}
 141
 142static int get_packet_data(int fd, char **src_buf, size_t *src_size,
 143                           void *dst, unsigned size, int options)
 144{
 145        ssize_t ret;
 146
 147        if (fd >= 0 && src_buf && *src_buf)
 148                die("BUG: multiple sources given to packet_read");
 149
 150        /* Read up to "size" bytes from our source, whatever it is. */
 151        if (src_buf && *src_buf) {
 152                ret = size < *src_size ? size : *src_size;
 153                memcpy(dst, *src_buf, ret);
 154                *src_buf += ret;
 155                *src_size -= ret;
 156        } else {
 157                ret = read_in_full(fd, dst, size);
 158                if (ret < 0)
 159                        die_errno("read error");
 160        }
 161
 162        /* And complain if we didn't get enough bytes to satisfy the read. */
 163        if (ret < size) {
 164                if (options & PACKET_READ_GENTLE_ON_EOF)
 165                        return -1;
 166
 167                die("The remote end hung up unexpectedly");
 168        }
 169
 170        return ret;
 171}
 172
 173static int packet_length(const char *linelen)
 174{
 175        int n;
 176        int len = 0;
 177
 178        for (n = 0; n < 4; n++) {
 179                unsigned char c = linelen[n];
 180                len <<= 4;
 181                if (c >= '0' && c <= '9') {
 182                        len += c - '0';
 183                        continue;
 184                }
 185                if (c >= 'a' && c <= 'f') {
 186                        len += c - 'a' + 10;
 187                        continue;
 188                }
 189                if (c >= 'A' && c <= 'F') {
 190                        len += c - 'A' + 10;
 191                        continue;
 192                }
 193                return -1;
 194        }
 195        return len;
 196}
 197
 198int packet_read(int fd, char **src_buf, size_t *src_len,
 199                char *buffer, unsigned size, int options)
 200{
 201        int len, ret;
 202        char linelen[4];
 203
 204        ret = get_packet_data(fd, src_buf, src_len, linelen, 4, options);
 205        if (ret < 0)
 206                return ret;
 207        len = packet_length(linelen);
 208        if (len < 0)
 209                die("protocol error: bad line length character: %.4s", linelen);
 210        if (!len) {
 211                packet_trace("0000", 4, 0);
 212                return 0;
 213        }
 214        len -= 4;
 215        if (len >= size)
 216                die("protocol error: bad line length %d", len);
 217        ret = get_packet_data(fd, src_buf, src_len, buffer, len, options);
 218        if (ret < 0)
 219                return ret;
 220
 221        if ((options & PACKET_READ_CHOMP_NEWLINE) &&
 222            len && buffer[len-1] == '\n')
 223                len--;
 224
 225        buffer[len] = 0;
 226        packet_trace(buffer, len, 0);
 227        return len;
 228}
 229
 230static char *packet_read_line_generic(int fd,
 231                                      char **src, size_t *src_len,
 232                                      int *dst_len)
 233{
 234        int len = packet_read(fd, src, src_len,
 235                              packet_buffer, sizeof(packet_buffer),
 236                              PACKET_READ_CHOMP_NEWLINE);
 237        if (dst_len)
 238                *dst_len = len;
 239        return len ? packet_buffer : NULL;
 240}
 241
 242char *packet_read_line(int fd, int *len_p)
 243{
 244        return packet_read_line_generic(fd, NULL, NULL, len_p);
 245}
 246
 247char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len)
 248{
 249        return packet_read_line_generic(-1, src, src_len, dst_len);
 250}