diff options
Diffstat (limited to 'src/basic/io-util.c')
-rw-r--r-- | src/basic/io-util.c | 264 |
1 files changed, 0 insertions, 264 deletions
diff --git a/src/basic/io-util.c b/src/basic/io-util.c deleted file mode 100644 index 3ec8d61236..0000000000 --- a/src/basic/io-util.c +++ /dev/null @@ -1,264 +0,0 @@ -/*** - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. -***/ - -#include <errno.h> -#include <limits.h> -#include <poll.h> -#include <stdio.h> -#include <time.h> -#include <unistd.h> - -#include "io-util.h" -#include "time-util.h" - -int flush_fd(int fd) { - struct pollfd pollfd = { - .fd = fd, - .events = POLLIN, - }; - - for (;;) { - char buf[LINE_MAX]; - ssize_t l; - int r; - - r = poll(&pollfd, 1, 0); - if (r < 0) { - if (errno == EINTR) - continue; - - return -errno; - - } else if (r == 0) - return 0; - - l = read(fd, buf, sizeof(buf)); - if (l < 0) { - - if (errno == EINTR) - continue; - - if (errno == EAGAIN) - return 0; - - return -errno; - } else if (l == 0) - return 0; - } -} - -ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) { - uint8_t *p = buf; - ssize_t n = 0; - - assert(fd >= 0); - assert(buf); - - /* If called with nbytes == 0, let's call read() at least - * once, to validate the operation */ - - if (nbytes > (size_t) SSIZE_MAX) - return -EINVAL; - - do { - ssize_t k; - - k = read(fd, p, nbytes); - if (k < 0) { - if (errno == EINTR) - continue; - - if (errno == EAGAIN && do_poll) { - - /* We knowingly ignore any return value here, - * and expect that any error/EOF is reported - * via read() */ - - (void) fd_wait_for_event(fd, POLLIN, USEC_INFINITY); - continue; - } - - return n > 0 ? n : -errno; - } - - if (k == 0) - return n; - - assert((size_t) k <= nbytes); - - p += k; - nbytes -= k; - n += k; - } while (nbytes > 0); - - return n; -} - -int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll) { - ssize_t n; - - n = loop_read(fd, buf, nbytes, do_poll); - if (n < 0) - return (int) n; - if ((size_t) n != nbytes) - return -EIO; - - return 0; -} - -int loop_write(int fd, const void *buf, size_t nbytes, bool do_poll) { - const uint8_t *p = buf; - - assert(fd >= 0); - assert(buf); - - if (nbytes > (size_t) SSIZE_MAX) - return -EINVAL; - - do { - ssize_t k; - - k = write(fd, p, nbytes); - if (k < 0) { - if (errno == EINTR) - continue; - - if (errno == EAGAIN && do_poll) { - /* We knowingly ignore any return value here, - * and expect that any error/EOF is reported - * via write() */ - - (void) fd_wait_for_event(fd, POLLOUT, USEC_INFINITY); - continue; - } - - return -errno; - } - - if (_unlikely_(nbytes > 0 && k == 0)) /* Can't really happen */ - return -EIO; - - assert((size_t) k <= nbytes); - - p += k; - nbytes -= k; - } while (nbytes > 0); - - return 0; -} - -int pipe_eof(int fd) { - struct pollfd pollfd = { - .fd = fd, - .events = POLLIN|POLLHUP, - }; - - int r; - - r = poll(&pollfd, 1, 0); - if (r < 0) - return -errno; - - if (r == 0) - return 0; - - return pollfd.revents & POLLHUP; -} - -int fd_wait_for_event(int fd, int event, usec_t t) { - - struct pollfd pollfd = { - .fd = fd, - .events = event, - }; - - struct timespec ts; - int r; - - r = ppoll(&pollfd, 1, t == USEC_INFINITY ? NULL : timespec_store(&ts, t), NULL); - if (r < 0) - return -errno; - - if (r == 0) - return 0; - - return pollfd.revents; -} - -static size_t nul_length(const uint8_t *p, size_t sz) { - size_t n = 0; - - while (sz > 0) { - if (*p != 0) - break; - - n++; - p++; - sz--; - } - - return n; -} - -ssize_t sparse_write(int fd, const void *p, size_t sz, size_t run_length) { - const uint8_t *q, *w, *e; - ssize_t l; - - q = w = p; - e = q + sz; - while (q < e) { - size_t n; - - n = nul_length(q, e - q); - - /* If there are more than the specified run length of - * NUL bytes, or if this is the beginning or the end - * of the buffer, then seek instead of write */ - if ((n > run_length) || - (n > 0 && q == p) || - (n > 0 && q + n >= e)) { - if (q > w) { - l = write(fd, w, q - w); - if (l < 0) - return -errno; - if (l != q -w) - return -EIO; - } - - if (lseek(fd, n, SEEK_CUR) == (off_t) -1) - return -errno; - - q += n; - w = q; - } else if (n > 0) - q += n; - else - q ++; - } - - if (q > w) { - l = write(fd, w, q - w); - if (l < 0) - return -errno; - if (l != q - w) - return -EIO; - } - - return q - (const uint8_t*) p; -} |