| 1 | /* -*- c-file-style: "linux" -*- |
| 2 | * |
| 3 | * Copyright (C) 1996-2001 by Andrew Tridgell |
| 4 | * Copyright (C) Paul Mackerras 1996 |
| 5 | * Copyright (C) 2001, 2002 by Martin Pool <mbp@samba.org> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file io.c |
| 24 | * |
| 25 | * Socket and pipe IO utilities used in rsync. |
| 26 | * |
| 27 | * rsync provides its own multiplexing system, which is used to send |
| 28 | * stderr and stdout over a single socket. We need this because |
| 29 | * stdout normally carries the binary data stream, and stderr all our |
| 30 | * error messages. |
| 31 | * |
| 32 | * For historical reasons this is off during the start of the |
| 33 | * connection, but it's switched on quite early using |
| 34 | * io_start_multiplex_out() and io_start_multiplex_in(). |
| 35 | **/ |
| 36 | |
| 37 | #include "rsync.h" |
| 38 | |
| 39 | /** If no timeout is specified then use a 60 second select timeout */ |
| 40 | #define SELECT_TIMEOUT 60 |
| 41 | |
| 42 | static int io_multiplexing_out; |
| 43 | static int io_multiplexing_in; |
| 44 | static int multiplex_in_fd; |
| 45 | static int multiplex_out_fd; |
| 46 | static time_t last_io; |
| 47 | static int no_flush; |
| 48 | |
| 49 | extern int bwlimit; |
| 50 | extern int verbose; |
| 51 | extern int io_timeout; |
| 52 | extern struct stats stats; |
| 53 | |
| 54 | |
| 55 | /** |
| 56 | * The connection might be dropped at some point; perhaps because the |
| 57 | * remote instance crashed. Just giving the offset on the stream is |
| 58 | * not very helpful. So instead we try to make io_phase_name point to |
| 59 | * something useful. |
| 60 | **/ |
| 61 | const char *io_phase_name = "unknown"; |
| 62 | |
| 63 | |
| 64 | /** Ignore EOF errors while reading a module listing if the remote |
| 65 | version is 24 or less. */ |
| 66 | int kludge_around_eof = False; |
| 67 | |
| 68 | |
| 69 | static int io_error_fd = -1; |
| 70 | |
| 71 | static void read_loop(int fd, char *buf, size_t len); |
| 72 | |
| 73 | static void check_timeout(void) |
| 74 | { |
| 75 | extern int am_server, am_daemon; |
| 76 | time_t t; |
| 77 | |
| 78 | err_list_push(); |
| 79 | |
| 80 | if (!io_timeout) return; |
| 81 | |
| 82 | if (!last_io) { |
| 83 | last_io = time(NULL); |
| 84 | return; |
| 85 | } |
| 86 | |
| 87 | t = time(NULL); |
| 88 | |
| 89 | if (last_io && io_timeout && (t-last_io) >= io_timeout) { |
| 90 | if (!am_server && !am_daemon) { |
| 91 | rprintf(FERROR,"io timeout after %d seconds - exiting\n", |
| 92 | (int)(t-last_io)); |
| 93 | } |
| 94 | exit_cleanup(RERR_TIMEOUT); |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | /** Setup the fd used to propogate errors */ |
| 99 | void io_set_error_fd(int fd) |
| 100 | { |
| 101 | io_error_fd = fd; |
| 102 | } |
| 103 | |
| 104 | /** Read some data from the error fd and write it to the write log code */ |
| 105 | static void read_error_fd(void) |
| 106 | { |
| 107 | char buf[200]; |
| 108 | size_t n; |
| 109 | int fd = io_error_fd; |
| 110 | int tag, len; |
| 111 | |
| 112 | /* io_error_fd is temporarily disabled -- is this meant to |
| 113 | * prevent indefinite recursion? */ |
| 114 | io_error_fd = -1; |
| 115 | |
| 116 | read_loop(fd, buf, 4); |
| 117 | tag = IVAL(buf, 0); |
| 118 | |
| 119 | len = tag & 0xFFFFFF; |
| 120 | tag = tag >> 24; |
| 121 | tag -= MPLEX_BASE; |
| 122 | |
| 123 | while (len) { |
| 124 | n = len; |
| 125 | if (n > (sizeof(buf)-1)) |
| 126 | n = sizeof(buf)-1; |
| 127 | read_loop(fd, buf, n); |
| 128 | rwrite((enum logcode)tag, buf, n); |
| 129 | len -= n; |
| 130 | } |
| 131 | |
| 132 | io_error_fd = fd; |
| 133 | } |
| 134 | |
| 135 | |
| 136 | /** |
| 137 | * It's almost always an error to get an EOF when we're trying to read |
| 138 | * from the network, because the protocol is self-terminating. |
| 139 | * |
| 140 | * However, there is one unfortunate cases where it is not, which is |
| 141 | * rsync <2.4.6 sending a list of modules on a server, since the list |
| 142 | * is terminated by closing the socket. So, for the section of the |
| 143 | * program where that is a problem (start_socket_client), |
| 144 | * kludge_around_eof is True and we just exit. |
| 145 | */ |
| 146 | static void whine_about_eof (void) |
| 147 | { |
| 148 | if (kludge_around_eof) |
| 149 | exit_cleanup (0); |
| 150 | else { |
| 151 | rprintf (FERROR, |
| 152 | "%s: connection unexpectedly closed " |
| 153 | "(%.0f bytes read so far)\n", |
| 154 | RSYNC_NAME, (double)stats.total_read); |
| 155 | |
| 156 | exit_cleanup (RERR_STREAMIO); |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | |
| 161 | static void die_from_readerr (int err) |
| 162 | { |
| 163 | /* this prevents us trying to write errors on a dead socket */ |
| 164 | io_multiplexing_close(); |
| 165 | |
| 166 | rprintf(FERROR, "%s: read error: %s\n", |
| 167 | RSYNC_NAME, strerror (err)); |
| 168 | exit_cleanup(RERR_STREAMIO); |
| 169 | } |
| 170 | |
| 171 | |
| 172 | /** |
| 173 | * Read from a socket with IO timeout. return the number of bytes |
| 174 | * read. If no bytes can be read then exit, never return a number <= 0. |
| 175 | * |
| 176 | * TODO: If the remote shell connection fails, then current versions |
| 177 | * actually report an "unexpected EOF" error here. Since it's a |
| 178 | * fairly common mistake to try to use rsh when ssh is required, we |
| 179 | * should trap that: if we fail to read any data at all, we should |
| 180 | * give a better explanation. We can tell whether the connection has |
| 181 | * started by looking e.g. at whether the remote version is known yet. |
| 182 | */ |
| 183 | static int read_timeout (int fd, char *buf, size_t len) |
| 184 | { |
| 185 | int n, ret=0; |
| 186 | |
| 187 | io_flush(); |
| 188 | |
| 189 | while (ret == 0) { |
| 190 | /* until we manage to read *something* */ |
| 191 | fd_set fds; |
| 192 | struct timeval tv; |
| 193 | int fd_count = fd+1; |
| 194 | int count; |
| 195 | |
| 196 | FD_ZERO(&fds); |
| 197 | FD_SET(fd, &fds); |
| 198 | if (io_error_fd != -1) { |
| 199 | FD_SET(io_error_fd, &fds); |
| 200 | if (io_error_fd > fd) fd_count = io_error_fd+1; |
| 201 | } |
| 202 | |
| 203 | tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT; |
| 204 | tv.tv_usec = 0; |
| 205 | |
| 206 | errno = 0; |
| 207 | |
| 208 | count = select(fd_count, &fds, NULL, NULL, &tv); |
| 209 | |
| 210 | if (count == 0) { |
| 211 | check_timeout(); |
| 212 | } |
| 213 | |
| 214 | if (count <= 0) { |
| 215 | if (errno == EBADF) { |
| 216 | exit_cleanup(RERR_SOCKETIO); |
| 217 | } |
| 218 | continue; |
| 219 | } |
| 220 | |
| 221 | if (io_error_fd != -1 && FD_ISSET(io_error_fd, &fds)) { |
| 222 | read_error_fd(); |
| 223 | } |
| 224 | |
| 225 | if (!FD_ISSET(fd, &fds)) continue; |
| 226 | |
| 227 | n = read(fd, buf, len); |
| 228 | |
| 229 | if (n > 0) { |
| 230 | buf += n; |
| 231 | len -= n; |
| 232 | ret += n; |
| 233 | if (io_timeout) |
| 234 | last_io = time(NULL); |
| 235 | continue; |
| 236 | } else if (n == 0) { |
| 237 | whine_about_eof (); |
| 238 | return -1; /* doesn't return */ |
| 239 | } else if (n == -1) { |
| 240 | if (errno == EINTR || errno == EWOULDBLOCK || |
| 241 | errno == EAGAIN) |
| 242 | continue; |
| 243 | else |
| 244 | die_from_readerr (errno); |
| 245 | } |
| 246 | } |
| 247 | |
| 248 | return ret; |
| 249 | } |
| 250 | |
| 251 | |
| 252 | |
| 253 | |
| 254 | /** |
| 255 | * Continue trying to read len bytes - don't return until len has been |
| 256 | * read. |
| 257 | **/ |
| 258 | static void read_loop (int fd, char *buf, size_t len) |
| 259 | { |
| 260 | while (len) { |
| 261 | int n = read_timeout(fd, buf, len); |
| 262 | |
| 263 | buf += n; |
| 264 | len -= n; |
| 265 | } |
| 266 | } |
| 267 | |
| 268 | |
| 269 | /** |
| 270 | * Read from the file descriptor handling multiplexing - return number |
| 271 | * of bytes read. |
| 272 | * |
| 273 | * Never returns <= 0. |
| 274 | */ |
| 275 | static int read_unbuffered(int fd, char *buf, size_t len) |
| 276 | { |
| 277 | static size_t remaining; |
| 278 | int tag, ret = 0; |
| 279 | char line[1024]; |
| 280 | |
| 281 | if (!io_multiplexing_in || fd != multiplex_in_fd) |
| 282 | return read_timeout(fd, buf, len); |
| 283 | |
| 284 | while (ret == 0) { |
| 285 | if (remaining) { |
| 286 | len = MIN(len, remaining); |
| 287 | read_loop(fd, buf, len); |
| 288 | remaining -= len; |
| 289 | ret = len; |
| 290 | continue; |
| 291 | } |
| 292 | |
| 293 | read_loop(fd, line, 4); |
| 294 | tag = IVAL(line, 0); |
| 295 | |
| 296 | remaining = tag & 0xFFFFFF; |
| 297 | tag = tag >> 24; |
| 298 | |
| 299 | if (tag == MPLEX_BASE) |
| 300 | continue; |
| 301 | |
| 302 | tag -= MPLEX_BASE; |
| 303 | |
| 304 | if (tag != FERROR && tag != FINFO) { |
| 305 | rprintf(FERROR, "unexpected tag %d\n", tag); |
| 306 | exit_cleanup(RERR_STREAMIO); |
| 307 | } |
| 308 | |
| 309 | if (remaining > sizeof(line) - 1) { |
| 310 | rprintf(FERROR, "multiplexing overflow %d\n\n", |
| 311 | remaining); |
| 312 | exit_cleanup(RERR_STREAMIO); |
| 313 | } |
| 314 | |
| 315 | read_loop(fd, line, remaining); |
| 316 | line[remaining] = 0; |
| 317 | |
| 318 | rprintf((enum logcode) tag, "%s", line); |
| 319 | remaining = 0; |
| 320 | } |
| 321 | |
| 322 | return ret; |
| 323 | } |
| 324 | |
| 325 | |
| 326 | |
| 327 | /** |
| 328 | * Do a buffered read from @p fd. Don't return until all @p n bytes |
| 329 | * have been read. If all @p n can't be read then exit with an |
| 330 | * error. |
| 331 | **/ |
| 332 | static void readfd (int fd, char *buffer, size_t N) |
| 333 | { |
| 334 | int ret; |
| 335 | size_t total=0; |
| 336 | |
| 337 | while (total < N) { |
| 338 | io_flush(); |
| 339 | |
| 340 | ret = read_unbuffered (fd, buffer + total, N-total); |
| 341 | total += ret; |
| 342 | } |
| 343 | |
| 344 | stats.total_read += total; |
| 345 | } |
| 346 | |
| 347 | |
| 348 | int32 read_int(int f) |
| 349 | { |
| 350 | char b[4]; |
| 351 | int32 ret; |
| 352 | |
| 353 | readfd(f,b,4); |
| 354 | ret = IVAL(b,0); |
| 355 | if (ret == (int32)0xffffffff) return -1; |
| 356 | return ret; |
| 357 | } |
| 358 | |
| 359 | int64 read_longint(int f) |
| 360 | { |
| 361 | extern int remote_version; |
| 362 | int64 ret; |
| 363 | char b[8]; |
| 364 | ret = read_int(f); |
| 365 | |
| 366 | if ((int32)ret != (int32)0xffffffff) { |
| 367 | return ret; |
| 368 | } |
| 369 | |
| 370 | #ifdef NO_INT64 |
| 371 | rprintf(FERROR,"Integer overflow - attempted 64 bit offset\n"); |
| 372 | exit_cleanup(RERR_UNSUPPORTED); |
| 373 | #else |
| 374 | if (remote_version >= 16) { |
| 375 | readfd(f,b,8); |
| 376 | ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32); |
| 377 | } |
| 378 | #endif |
| 379 | |
| 380 | return ret; |
| 381 | } |
| 382 | |
| 383 | void read_buf(int f,char *buf,size_t len) |
| 384 | { |
| 385 | readfd(f,buf,len); |
| 386 | } |
| 387 | |
| 388 | void read_sbuf(int f,char *buf,size_t len) |
| 389 | { |
| 390 | read_buf (f,buf,len); |
| 391 | buf[len] = 0; |
| 392 | } |
| 393 | |
| 394 | unsigned char read_byte(int f) |
| 395 | { |
| 396 | unsigned char c; |
| 397 | read_buf (f, (char *)&c, 1); |
| 398 | return c; |
| 399 | } |
| 400 | |
| 401 | |
| 402 | /** |
| 403 | * Sleep after writing to limit I/O bandwidth usage. |
| 404 | * |
| 405 | * @todo Rather than sleeping after each write, it might be better to |
| 406 | * use some kind of averaging. The current algorithm seems to always |
| 407 | * use a bit less bandwidth than specified, because it doesn't make up |
| 408 | * for slow periods. But arguably this is a feature. In addition, we |
| 409 | * ought to take the time used to write the data into account. |
| 410 | **/ |
| 411 | static void sleep_for_bwlimit(int bytes_written) |
| 412 | { |
| 413 | struct timeval tv; |
| 414 | |
| 415 | if (!bwlimit) |
| 416 | return; |
| 417 | |
| 418 | assert(bytes_written > 0); |
| 419 | assert(bwlimit > 0); |
| 420 | |
| 421 | tv.tv_usec = bytes_written * 1000 / bwlimit; |
| 422 | tv.tv_sec = tv.tv_usec / 1000000; |
| 423 | tv.tv_usec = tv.tv_usec % 1000000; |
| 424 | |
| 425 | select(0, NULL, NULL, NULL, &tv); |
| 426 | } |
| 427 | |
| 428 | |
| 429 | /** |
| 430 | * Write len bytes to the file descriptor @p fd. |
| 431 | * |
| 432 | * This function underlies the multiplexing system. The body of the |
| 433 | * application never calls this function directly. |
| 434 | **/ |
| 435 | static void writefd_unbuffered(int fd,char *buf,size_t len) |
| 436 | { |
| 437 | size_t total = 0; |
| 438 | fd_set w_fds, r_fds; |
| 439 | int fd_count, count; |
| 440 | struct timeval tv; |
| 441 | |
| 442 | err_list_push(); |
| 443 | |
| 444 | no_flush++; |
| 445 | |
| 446 | while (total < len) { |
| 447 | FD_ZERO(&w_fds); |
| 448 | FD_ZERO(&r_fds); |
| 449 | FD_SET(fd,&w_fds); |
| 450 | fd_count = fd; |
| 451 | |
| 452 | if (io_error_fd != -1) { |
| 453 | FD_SET(io_error_fd,&r_fds); |
| 454 | if (io_error_fd > fd_count) |
| 455 | fd_count = io_error_fd; |
| 456 | } |
| 457 | |
| 458 | tv.tv_sec = io_timeout?io_timeout:SELECT_TIMEOUT; |
| 459 | tv.tv_usec = 0; |
| 460 | |
| 461 | errno = 0; |
| 462 | |
| 463 | count = select(fd_count+1, |
| 464 | io_error_fd != -1?&r_fds:NULL, |
| 465 | &w_fds,NULL, |
| 466 | &tv); |
| 467 | |
| 468 | if (count == 0) { |
| 469 | check_timeout(); |
| 470 | } |
| 471 | |
| 472 | if (count <= 0) { |
| 473 | if (errno == EBADF) { |
| 474 | exit_cleanup(RERR_SOCKETIO); |
| 475 | } |
| 476 | continue; |
| 477 | } |
| 478 | |
| 479 | if (io_error_fd != -1 && FD_ISSET(io_error_fd, &r_fds)) { |
| 480 | read_error_fd(); |
| 481 | } |
| 482 | |
| 483 | if (FD_ISSET(fd, &w_fds)) { |
| 484 | int ret; |
| 485 | size_t n = len-total; |
| 486 | ret = write(fd,buf+total,n); |
| 487 | |
| 488 | if (ret == -1 && errno == EINTR) { |
| 489 | continue; |
| 490 | } |
| 491 | |
| 492 | if (ret == -1 && |
| 493 | (errno == EWOULDBLOCK || errno == EAGAIN)) { |
| 494 | msleep(1); |
| 495 | continue; |
| 496 | } |
| 497 | |
| 498 | if (ret <= 0) { |
| 499 | /* Don't try to write errors back |
| 500 | * across the stream */ |
| 501 | io_multiplexing_close(); |
| 502 | rprintf(FERROR, RSYNC_NAME |
| 503 | ": writefd_unbuffered failed to write %ld bytes: phase \"%s\": %s\n", |
| 504 | (long) len, io_phase_name, |
| 505 | strerror(errno)); |
| 506 | exit_cleanup(RERR_STREAMIO); |
| 507 | } |
| 508 | |
| 509 | sleep_for_bwlimit(ret); |
| 510 | |
| 511 | total += ret; |
| 512 | |
| 513 | if (io_timeout) |
| 514 | last_io = time(NULL); |
| 515 | } |
| 516 | } |
| 517 | |
| 518 | no_flush--; |
| 519 | } |
| 520 | |
| 521 | |
| 522 | static char *io_buffer; |
| 523 | static int io_buffer_count; |
| 524 | |
| 525 | void io_start_buffering(int fd) |
| 526 | { |
| 527 | if (io_buffer) return; |
| 528 | multiplex_out_fd = fd; |
| 529 | io_buffer = (char *)malloc(IO_BUFFER_SIZE); |
| 530 | if (!io_buffer) out_of_memory("writefd"); |
| 531 | io_buffer_count = 0; |
| 532 | } |
| 533 | |
| 534 | /** |
| 535 | * Write an message to a multiplexed stream. If this fails then rsync |
| 536 | * exits. |
| 537 | **/ |
| 538 | static void mplex_write(int fd, enum logcode code, char *buf, size_t len) |
| 539 | { |
| 540 | char buffer[4096]; |
| 541 | size_t n = len; |
| 542 | |
| 543 | SIVAL(buffer, 0, ((MPLEX_BASE + (int)code)<<24) + len); |
| 544 | |
| 545 | if (n > (sizeof(buffer)-4)) { |
| 546 | n = sizeof(buffer)-4; |
| 547 | } |
| 548 | |
| 549 | memcpy(&buffer[4], buf, n); |
| 550 | writefd_unbuffered(fd, buffer, n+4); |
| 551 | |
| 552 | len -= n; |
| 553 | buf += n; |
| 554 | |
| 555 | if (len) { |
| 556 | writefd_unbuffered(fd, buf, len); |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | |
| 561 | void io_flush(void) |
| 562 | { |
| 563 | int fd = multiplex_out_fd; |
| 564 | |
| 565 | err_list_push(); |
| 566 | |
| 567 | if (!io_buffer_count || no_flush) return; |
| 568 | |
| 569 | if (io_multiplexing_out) { |
| 570 | mplex_write(fd, FNONE, io_buffer, io_buffer_count); |
| 571 | } else { |
| 572 | writefd_unbuffered(fd, io_buffer, io_buffer_count); |
| 573 | } |
| 574 | io_buffer_count = 0; |
| 575 | } |
| 576 | |
| 577 | |
| 578 | void io_end_buffering(void) |
| 579 | { |
| 580 | io_flush(); |
| 581 | if (!io_multiplexing_out) { |
| 582 | free(io_buffer); |
| 583 | io_buffer = NULL; |
| 584 | } |
| 585 | } |
| 586 | |
| 587 | static void writefd(int fd,char *buf,size_t len) |
| 588 | { |
| 589 | stats.total_written += len; |
| 590 | |
| 591 | err_list_push(); |
| 592 | |
| 593 | if (!io_buffer || fd != multiplex_out_fd) { |
| 594 | writefd_unbuffered(fd, buf, len); |
| 595 | return; |
| 596 | } |
| 597 | |
| 598 | while (len) { |
| 599 | int n = MIN((int) len, IO_BUFFER_SIZE-io_buffer_count); |
| 600 | if (n > 0) { |
| 601 | memcpy(io_buffer+io_buffer_count, buf, n); |
| 602 | buf += n; |
| 603 | len -= n; |
| 604 | io_buffer_count += n; |
| 605 | } |
| 606 | |
| 607 | if (io_buffer_count == IO_BUFFER_SIZE) io_flush(); |
| 608 | } |
| 609 | } |
| 610 | |
| 611 | |
| 612 | void write_int(int f,int32 x) |
| 613 | { |
| 614 | char b[4]; |
| 615 | SIVAL(b,0,x); |
| 616 | writefd(f,b,4); |
| 617 | } |
| 618 | |
| 619 | |
| 620 | /* |
| 621 | * Note: int64 may actually be a 32-bit type if ./configure couldn't find any |
| 622 | * 64-bit types on this platform. |
| 623 | */ |
| 624 | void write_longint(int f, int64 x) |
| 625 | { |
| 626 | extern int remote_version; |
| 627 | char b[8]; |
| 628 | |
| 629 | if (remote_version < 16 || x <= 0x7FFFFFFF) { |
| 630 | write_int(f, (int)x); |
| 631 | return; |
| 632 | } |
| 633 | |
| 634 | write_int(f, (int32)0xFFFFFFFF); |
| 635 | SIVAL(b,0,(x&0xFFFFFFFF)); |
| 636 | SIVAL(b,4,((x>>32)&0xFFFFFFFF)); |
| 637 | |
| 638 | writefd(f,b,8); |
| 639 | } |
| 640 | |
| 641 | void write_buf(int f,char *buf,size_t len) |
| 642 | { |
| 643 | writefd(f,buf,len); |
| 644 | } |
| 645 | |
| 646 | /** Write a string to the connection */ |
| 647 | static void write_sbuf(int f,char *buf) |
| 648 | { |
| 649 | write_buf(f, buf, strlen(buf)); |
| 650 | } |
| 651 | |
| 652 | |
| 653 | void write_byte(int f,unsigned char c) |
| 654 | { |
| 655 | write_buf(f,(char *)&c,1); |
| 656 | } |
| 657 | |
| 658 | |
| 659 | |
| 660 | /** |
| 661 | * Read a line of up to @p maxlen characters into @p buf. Does not |
| 662 | * contain a trailing newline or carriage return. |
| 663 | * |
| 664 | * @return 1 for success; 0 for io error or truncation. |
| 665 | **/ |
| 666 | int read_line(int f, char *buf, size_t maxlen) |
| 667 | { |
| 668 | while (maxlen) { |
| 669 | buf[0] = 0; |
| 670 | read_buf(f, buf, 1); |
| 671 | if (buf[0] == 0) |
| 672 | return 0; |
| 673 | if (buf[0] == '\n') { |
| 674 | buf[0] = 0; |
| 675 | break; |
| 676 | } |
| 677 | if (buf[0] != '\r') { |
| 678 | buf++; |
| 679 | maxlen--; |
| 680 | } |
| 681 | } |
| 682 | if (maxlen == 0) { |
| 683 | *buf = 0; |
| 684 | return 0; |
| 685 | } |
| 686 | |
| 687 | return 1; |
| 688 | } |
| 689 | |
| 690 | |
| 691 | void io_printf(int fd, const char *format, ...) |
| 692 | { |
| 693 | va_list ap; |
| 694 | char buf[1024]; |
| 695 | int len; |
| 696 | |
| 697 | va_start(ap, format); |
| 698 | len = vsnprintf(buf, sizeof(buf), format, ap); |
| 699 | va_end(ap); |
| 700 | |
| 701 | if (len < 0) exit_cleanup(RERR_STREAMIO); |
| 702 | |
| 703 | write_sbuf(fd, buf); |
| 704 | } |
| 705 | |
| 706 | |
| 707 | /** Setup for multiplexing an error stream with the data stream */ |
| 708 | void io_start_multiplex_out(int fd) |
| 709 | { |
| 710 | multiplex_out_fd = fd; |
| 711 | io_flush(); |
| 712 | io_start_buffering(fd); |
| 713 | io_multiplexing_out = 1; |
| 714 | } |
| 715 | |
| 716 | /** Setup for multiplexing an error stream with the data stream */ |
| 717 | void io_start_multiplex_in(int fd) |
| 718 | { |
| 719 | multiplex_in_fd = fd; |
| 720 | io_flush(); |
| 721 | io_multiplexing_in = 1; |
| 722 | } |
| 723 | |
| 724 | /** Write an message to the multiplexed error stream */ |
| 725 | int io_multiplex_write(enum logcode code, char *buf, size_t len) |
| 726 | { |
| 727 | if (!io_multiplexing_out) return 0; |
| 728 | |
| 729 | io_flush(); |
| 730 | stats.total_written += (len+4); |
| 731 | mplex_write(multiplex_out_fd, code, buf, len); |
| 732 | return 1; |
| 733 | } |
| 734 | |
| 735 | /** Stop output multiplexing */ |
| 736 | void io_multiplexing_close(void) |
| 737 | { |
| 738 | io_multiplexing_out = 0; |
| 739 | } |
| 740 | |