pkt-line.con commit Merge branch 'ds/include-exclude' (9755f70)
   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        if (write_in_full(fd, "0000", 4) < 0)
  92                die_errno(_("unable to write flush packet"));
  93}
  94
  95void packet_delim(int fd)
  96{
  97        packet_trace("0001", 4, 1);
  98        if (write_in_full(fd, "0001", 4) < 0)
  99                die_errno(_("unable to write delim packet"));
 100}
 101
 102int packet_flush_gently(int fd)
 103{
 104        packet_trace("0000", 4, 1);
 105        if (write_in_full(fd, "0000", 4) < 0)
 106                return error(_("flush packet write failed"));
 107        return 0;
 108}
 109
 110void packet_buf_flush(struct strbuf *buf)
 111{
 112        packet_trace("0000", 4, 1);
 113        strbuf_add(buf, "0000", 4);
 114}
 115
 116void packet_buf_delim(struct strbuf *buf)
 117{
 118        packet_trace("0001", 4, 1);
 119        strbuf_add(buf, "0001", 4);
 120}
 121
 122void set_packet_header(char *buf, int size)
 123{
 124        static char hexchar[] = "0123456789abcdef";
 125
 126        #define hex(a) (hexchar[(a) & 15])
 127        buf[0] = hex(size >> 12);
 128        buf[1] = hex(size >> 8);
 129        buf[2] = hex(size >> 4);
 130        buf[3] = hex(size);
 131        #undef hex
 132}
 133
 134static void format_packet(struct strbuf *out, const char *prefix,
 135                          const char *fmt, va_list args)
 136{
 137        size_t orig_len, n;
 138
 139        orig_len = out->len;
 140        strbuf_addstr(out, "0000");
 141        strbuf_addstr(out, prefix);
 142        strbuf_vaddf(out, fmt, args);
 143        n = out->len - orig_len;
 144
 145        if (n > LARGE_PACKET_MAX)
 146                die(_("protocol error: impossibly long line"));
 147
 148        set_packet_header(&out->buf[orig_len], n);
 149        packet_trace(out->buf + orig_len + 4, n - 4, 1);
 150}
 151
 152static int packet_write_fmt_1(int fd, int gently, const char *prefix,
 153                              const char *fmt, va_list args)
 154{
 155        static struct strbuf buf = STRBUF_INIT;
 156
 157        strbuf_reset(&buf);
 158        format_packet(&buf, prefix, fmt, args);
 159        if (write_in_full(fd, buf.buf, buf.len) < 0) {
 160                if (!gently) {
 161                        check_pipe(errno);
 162                        die_errno(_("packet write with format failed"));
 163                }
 164                return error(_("packet write with format failed"));
 165        }
 166
 167        return 0;
 168}
 169
 170void packet_write_fmt(int fd, const char *fmt, ...)
 171{
 172        va_list args;
 173
 174        va_start(args, fmt);
 175        packet_write_fmt_1(fd, 0, "", fmt, args);
 176        va_end(args);
 177}
 178
 179int packet_write_fmt_gently(int fd, const char *fmt, ...)
 180{
 181        int status;
 182        va_list args;
 183
 184        va_start(args, fmt);
 185        status = packet_write_fmt_1(fd, 1, "", fmt, args);
 186        va_end(args);
 187        return status;
 188}
 189
 190static int packet_write_gently(const int fd_out, const char *buf, size_t size)
 191{
 192        static char packet_write_buffer[LARGE_PACKET_MAX];
 193        size_t packet_size;
 194
 195        if (size > sizeof(packet_write_buffer) - 4)
 196                return error(_("packet write failed - data exceeds max packet size"));
 197
 198        packet_trace(buf, size, 1);
 199        packet_size = size + 4;
 200        set_packet_header(packet_write_buffer, packet_size);
 201        memcpy(packet_write_buffer + 4, buf, size);
 202        if (write_in_full(fd_out, packet_write_buffer, packet_size) < 0)
 203                return error(_("packet write failed"));
 204        return 0;
 205}
 206
 207void packet_write(int fd_out, const char *buf, size_t size)
 208{
 209        if (packet_write_gently(fd_out, buf, size))
 210                die_errno(_("packet write failed"));
 211}
 212
 213void packet_buf_write(struct strbuf *buf, const char *fmt, ...)
 214{
 215        va_list args;
 216
 217        va_start(args, fmt);
 218        format_packet(buf, "", fmt, args);
 219        va_end(args);
 220}
 221
 222void packet_buf_write_len(struct strbuf *buf, const char *data, size_t len)
 223{
 224        size_t orig_len, n;
 225
 226        orig_len = buf->len;
 227        strbuf_addstr(buf, "0000");
 228        strbuf_add(buf, data, len);
 229        n = buf->len - orig_len;
 230
 231        if (n > LARGE_PACKET_MAX)
 232                die(_("protocol error: impossibly long line"));
 233
 234        set_packet_header(&buf->buf[orig_len], n);
 235        packet_trace(data, len, 1);
 236}
 237
 238int write_packetized_from_fd(int fd_in, int fd_out)
 239{
 240        static char buf[LARGE_PACKET_DATA_MAX];
 241        int err = 0;
 242        ssize_t bytes_to_write;
 243
 244        while (!err) {
 245                bytes_to_write = xread(fd_in, buf, sizeof(buf));
 246                if (bytes_to_write < 0)
 247                        return COPY_READ_ERROR;
 248                if (bytes_to_write == 0)
 249                        break;
 250                err = packet_write_gently(fd_out, buf, bytes_to_write);
 251        }
 252        if (!err)
 253                err = packet_flush_gently(fd_out);
 254        return err;
 255}
 256
 257int write_packetized_from_buf(const char *src_in, size_t len, int fd_out)
 258{
 259        int err = 0;
 260        size_t bytes_written = 0;
 261        size_t bytes_to_write;
 262
 263        while (!err) {
 264                if ((len - bytes_written) > LARGE_PACKET_DATA_MAX)
 265                        bytes_to_write = LARGE_PACKET_DATA_MAX;
 266                else
 267                        bytes_to_write = len - bytes_written;
 268                if (bytes_to_write == 0)
 269                        break;
 270                err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
 271                bytes_written += bytes_to_write;
 272        }
 273        if (!err)
 274                err = packet_flush_gently(fd_out);
 275        return err;
 276}
 277
 278static int get_packet_data(int fd, char **src_buf, size_t *src_size,
 279                           void *dst, unsigned size, int options)
 280{
 281        ssize_t ret;
 282
 283        if (fd >= 0 && src_buf && *src_buf)
 284                BUG("multiple sources given to packet_read");
 285
 286        /* Read up to "size" bytes from our source, whatever it is. */
 287        if (src_buf && *src_buf) {
 288                ret = size < *src_size ? size : *src_size;
 289                memcpy(dst, *src_buf, ret);
 290                *src_buf += ret;
 291                *src_size -= ret;
 292        } else {
 293                ret = read_in_full(fd, dst, size);
 294                if (ret < 0)
 295                        die_errno(_("read error"));
 296        }
 297
 298        /* And complain if we didn't get enough bytes to satisfy the read. */
 299        if (ret != size) {
 300                if (options & PACKET_READ_GENTLE_ON_EOF)
 301                        return -1;
 302
 303                die(_("the remote end hung up unexpectedly"));
 304        }
 305
 306        return ret;
 307}
 308
 309static int packet_length(const char *linelen)
 310{
 311        int val = hex2chr(linelen);
 312        return (val < 0) ? val : (val << 8) | hex2chr(linelen + 2);
 313}
 314
 315enum packet_read_status packet_read_with_status(int fd, char **src_buffer,
 316                                                size_t *src_len, char *buffer,
 317                                                unsigned size, int *pktlen,
 318                                                int options)
 319{
 320        int len;
 321        char linelen[4];
 322
 323        if (get_packet_data(fd, src_buffer, src_len, linelen, 4, options) < 0) {
 324                *pktlen = -1;
 325                return PACKET_READ_EOF;
 326        }
 327
 328        len = packet_length(linelen);
 329
 330        if (len < 0) {
 331                die(_("protocol error: bad line length character: %.4s"), linelen);
 332        } else if (!len) {
 333                packet_trace("0000", 4, 0);
 334                *pktlen = 0;
 335                return PACKET_READ_FLUSH;
 336        } else if (len == 1) {
 337                packet_trace("0001", 4, 0);
 338                *pktlen = 0;
 339                return PACKET_READ_DELIM;
 340        } else if (len < 4) {
 341                die(_("protocol error: bad line length %d"), len);
 342        }
 343
 344        len -= 4;
 345        if ((unsigned)len >= size)
 346                die(_("protocol error: bad line length %d"), len);
 347
 348        if (get_packet_data(fd, src_buffer, src_len, buffer, len, options) < 0) {
 349                *pktlen = -1;
 350                return PACKET_READ_EOF;
 351        }
 352
 353        if ((options & PACKET_READ_CHOMP_NEWLINE) &&
 354            len && buffer[len-1] == '\n')
 355                len--;
 356
 357        buffer[len] = 0;
 358        packet_trace(buffer, len, 0);
 359
 360        if ((options & PACKET_READ_DIE_ON_ERR_PACKET) &&
 361            starts_with(buffer, "ERR "))
 362                die(_("remote error: %s"), buffer + 4);
 363
 364        *pktlen = len;
 365        return PACKET_READ_NORMAL;
 366}
 367
 368int packet_read(int fd, char **src_buffer, size_t *src_len,
 369                char *buffer, unsigned size, int options)
 370{
 371        int pktlen = -1;
 372
 373        packet_read_with_status(fd, src_buffer, src_len, buffer, size,
 374                                &pktlen, options);
 375
 376        return pktlen;
 377}
 378
 379static char *packet_read_line_generic(int fd,
 380                                      char **src, size_t *src_len,
 381                                      int *dst_len)
 382{
 383        int len = packet_read(fd, src, src_len,
 384                              packet_buffer, sizeof(packet_buffer),
 385                              PACKET_READ_CHOMP_NEWLINE);
 386        if (dst_len)
 387                *dst_len = len;
 388        return (len > 0) ? packet_buffer : NULL;
 389}
 390
 391char *packet_read_line(int fd, int *len_p)
 392{
 393        return packet_read_line_generic(fd, NULL, NULL, len_p);
 394}
 395
 396int packet_read_line_gently(int fd, int *dst_len, char **dst_line)
 397{
 398        int len = packet_read(fd, NULL, NULL,
 399                              packet_buffer, sizeof(packet_buffer),
 400                              PACKET_READ_CHOMP_NEWLINE|PACKET_READ_GENTLE_ON_EOF);
 401        if (dst_len)
 402                *dst_len = len;
 403        if (dst_line)
 404                *dst_line = (len > 0) ? packet_buffer : NULL;
 405        return len;
 406}
 407
 408char *packet_read_line_buf(char **src, size_t *src_len, int *dst_len)
 409{
 410        return packet_read_line_generic(-1, src, src_len, dst_len);
 411}
 412
 413ssize_t read_packetized_to_strbuf(int fd_in, struct strbuf *sb_out)
 414{
 415        int packet_len;
 416
 417        size_t orig_len = sb_out->len;
 418        size_t orig_alloc = sb_out->alloc;
 419
 420        for (;;) {
 421                strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
 422                packet_len = packet_read(fd_in, NULL, NULL,
 423                        /* strbuf_grow() above always allocates one extra byte to
 424                         * store a '\0' at the end of the string. packet_read()
 425                         * writes a '\0' extra byte at the end, too. Let it know
 426                         * that there is already room for the extra byte.
 427                         */
 428                        sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
 429                        PACKET_READ_GENTLE_ON_EOF);
 430                if (packet_len <= 0)
 431                        break;
 432                sb_out->len += packet_len;
 433        }
 434
 435        if (packet_len < 0) {
 436                if (orig_alloc == 0)
 437                        strbuf_release(sb_out);
 438                else
 439                        strbuf_setlen(sb_out, orig_len);
 440                return packet_len;
 441        }
 442        return sb_out->len - orig_len;
 443}
 444
 445int recv_sideband(const char *me, int in_stream, int out)
 446{
 447        char buf[LARGE_PACKET_MAX + 1];
 448        int len;
 449        struct strbuf scratch = STRBUF_INIT;
 450        enum sideband_type sideband_type;
 451
 452        while (1) {
 453                len = packet_read(in_stream, NULL, NULL, buf, LARGE_PACKET_MAX,
 454                                  0);
 455                if (!demultiplex_sideband(me, buf, len, 0, &scratch,
 456                                          &sideband_type))
 457                        continue;
 458                switch (sideband_type) {
 459                case SIDEBAND_PRIMARY:
 460                        write_or_die(out, buf + 1, len - 1);
 461                        break;
 462                default: /* errors: message already written */
 463                        return sideband_type;
 464                }
 465        }
 466}
 467
 468/* Packet Reader Functions */
 469void packet_reader_init(struct packet_reader *reader, int fd,
 470                        char *src_buffer, size_t src_len,
 471                        int options)
 472{
 473        memset(reader, 0, sizeof(*reader));
 474
 475        reader->fd = fd;
 476        reader->src_buffer = src_buffer;
 477        reader->src_len = src_len;
 478        reader->buffer = packet_buffer;
 479        reader->buffer_size = sizeof(packet_buffer);
 480        reader->options = options;
 481        reader->me = "git";
 482}
 483
 484enum packet_read_status packet_reader_read(struct packet_reader *reader)
 485{
 486        struct strbuf scratch = STRBUF_INIT;
 487
 488        if (reader->line_peeked) {
 489                reader->line_peeked = 0;
 490                return reader->status;
 491        }
 492
 493        /*
 494         * Consume all progress packets until a primary payload packet is
 495         * received
 496         */
 497        while (1) {
 498                enum sideband_type sideband_type;
 499                reader->status = packet_read_with_status(reader->fd,
 500                                                         &reader->src_buffer,
 501                                                         &reader->src_len,
 502                                                         reader->buffer,
 503                                                         reader->buffer_size,
 504                                                         &reader->pktlen,
 505                                                         reader->options);
 506                if (!reader->use_sideband)
 507                        break;
 508                if (demultiplex_sideband(reader->me, reader->buffer,
 509                                         reader->pktlen, 1, &scratch,
 510                                         &sideband_type))
 511                        break;
 512        }
 513
 514        if (reader->status == PACKET_READ_NORMAL)
 515                /* Skip the sideband designator if sideband is used */
 516                reader->line = reader->use_sideband ?
 517                        reader->buffer + 1 : reader->buffer;
 518        else
 519                reader->line = NULL;
 520
 521        return reader->status;
 522}
 523
 524enum packet_read_status packet_reader_peek(struct packet_reader *reader)
 525{
 526        /* Only allow peeking a single line */
 527        if (reader->line_peeked)
 528                return reader->status;
 529
 530        /* Peek a line by reading it and setting peeked flag */
 531        packet_reader_read(reader);
 532        reader->line_peeked = 1;
 533        return reader->status;
 534}
 535
 536void packet_writer_init(struct packet_writer *writer, int dest_fd)
 537{
 538        writer->dest_fd = dest_fd;
 539        writer->use_sideband = 0;
 540}
 541
 542void packet_writer_write(struct packet_writer *writer, const char *fmt, ...)
 543{
 544        va_list args;
 545
 546        va_start(args, fmt);
 547        packet_write_fmt_1(writer->dest_fd, 0,
 548                           writer->use_sideband ? "\001" : "", fmt, args);
 549        va_end(args);
 550}
 551
 552void packet_writer_error(struct packet_writer *writer, const char *fmt, ...)
 553{
 554        va_list args;
 555
 556        va_start(args, fmt);
 557        packet_write_fmt_1(writer->dest_fd, 0,
 558                           writer->use_sideband ? "\003" : "ERR ", fmt, args);
 559        va_end(args);
 560}
 561
 562void packet_writer_delim(struct packet_writer *writer)
 563{
 564        packet_delim(writer->dest_fd);
 565}
 566
 567void packet_writer_flush(struct packet_writer *writer)
 568{
 569        packet_flush(writer->dest_fd);
 570}