X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Ffile_io.c;h=9455ed63ad0cd6cec4abdd5f9d645738059d2d33;hb=2fc33f535a398ea85964c0e483c5692821d775f3;hp=2852571c413cb13ea1f29ae4174c1155779b7b11;hpb=61db93f82eca3fe9f7676355c709c58cc425a6ad;p=wimlib diff --git a/src/file_io.c b/src/file_io.c index 2852571c..9455ed63 100644 --- a/src/file_io.c +++ b/src/file_io.c @@ -5,42 +5,36 @@ /* * Copyright (C) 2013 Eric Biggers * - * This file is part of wimlib, a library for working with WIM files. + * This file 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 3 of the License, or (at your option) any + * later version. * - * wimlib is free software; you can redistribute it and/or modify it under the - * terms of the GNU General Public License as published by the Free - * Software Foundation; either version 3 of the License, or (at your option) - * any later version. - * - * wimlib 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 General Public License for more + * This file 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 General Public License - * along with wimlib; if not, see http://www.gnu.org/licenses/. + * You should have received a copy of the GNU Lesser General Public License + * along with this file; if not, see http://www.gnu.org/licenses/. */ #ifdef HAVE_CONFIG_H # include "config.h" #endif -#include "wimlib/assert.h" +#include +#include + #include "wimlib/error.h" #include "wimlib/file_io.h" #include "wimlib/util.h" #ifdef __WIN32__ # include "wimlib/win32.h" /* For pread(), pwrite() replacements */ -#else -# include /* for writev() and `struct iovec' */ #endif -#include -#include - - -/* Wrapper around read() that keeps retrying until all requested bytes have been - * read or until end-of file has occurred. +/* Wrapper around read() that checks for errors keeps retrying until all + * requested bytes have been read or until end-of file has occurred. * * Return values: * WIMLIB_ERR_SUCCESS (0) @@ -79,15 +73,17 @@ pipe_read(struct filedes *fd, void *buf, size_t count, off_t offset) { int ret; + /* Verify the offset. */ if (offset < fd->offset) { ERROR("Can't seek backwards in pipe " "(offset %"PRIu64" => %"PRIu64").\n" - " Make sure the WIM was captured as " - "pipable.", - fd->offset, offset); + " Make sure the WIM was captured as " + "pipable.", fd->offset, offset); errno = ESPIPE; return WIMLIB_ERR_RESOURCE_ORDER; } + + /* Manually seek to the requested position. */ while (fd->offset != offset) { size_t bytes_to_read = min(offset - fd->offset, BUFFER_SIZE); u8 dummy[bytes_to_read]; @@ -96,13 +92,15 @@ pipe_read(struct filedes *fd, void *buf, size_t count, off_t offset) if (ret) return ret; } + + /* Do the actual read. */ return full_read(fd, buf, count); } -/* Wrapper around pread() that keep retrying until all requested bytes have been - * read or until end-of file has occurred. This also transparently handle - * reading from pipe files, but the caller needs to be sure the requested offset - * is greater than or equal to the current offset, or else +/* Wrapper around pread() that checks for errors and keeps retrying until all + * requested bytes have been read or until end-of file has occurred. This also + * transparently handle reading from pipe files, but the caller needs to be sure + * the requested offset is greater than or equal to the current offset, or else * WIMLIB_ERR_RESOURCE_ORDER will be returned. * * Return values: @@ -110,7 +108,7 @@ pipe_read(struct filedes *fd, void *buf, size_t count, off_t offset) * WIMLIB_ERR_READ (errno set) * WIMLIB_ERR_UNEXPECTED_END_OF_FILE (errno set to 0) * WIMLIB_ERR_RESOURCE_ORDER (errno set to ESPIPE) - * */ + */ int full_pread(struct filedes *fd, void *buf, size_t count, off_t offset) { @@ -123,7 +121,7 @@ full_pread(struct filedes *fd, void *buf, size_t count, off_t offset) for (bytes_remaining = count; bytes_remaining != 0; bytes_remaining -= bytes_read, buf += bytes_read, - offset += bytes_read) + offset += bytes_read) { bytes_read = pread(fd->fd, buf, bytes_remaining, offset); if (unlikely(bytes_read <= 0)) { @@ -133,7 +131,6 @@ full_pread(struct filedes *fd, void *buf, size_t count, off_t offset) } else if (errno == EINTR) { continue; } else if (errno == ESPIPE) { - wimlib_assert(count == bytes_remaining); fd->is_pipe = 1; goto is_pipe; } else { @@ -147,8 +144,8 @@ is_pipe: return pipe_read(fd, buf, count, offset); } -/* Wrapper around write() that keeps retrying until all requested bytes have - * been written. +/* Wrapper around write() that checks for errors and keeps retrying until all + * requested bytes have been written. * * Return values: * WIMLIB_ERR_SUCCESS (0) @@ -176,8 +173,8 @@ full_write(struct filedes *fd, const void *buf, size_t count) } -/* Wrapper around pwrite() that keep retrying until all requested bytes have been - * written. +/* Wrapper around pwrite() that checks for errors and keeps retrying until all + * requested bytes have been written. * * Return values: * WIMLIB_ERR_SUCCESS (0) @@ -192,7 +189,7 @@ full_pwrite(struct filedes *fd, const void *buf, size_t count, off_t offset) for (bytes_remaining = count; bytes_remaining != 0; bytes_remaining -= bytes_written, buf += bytes_written, - offset += bytes_written) + offset += bytes_written) { bytes_written = pwrite(fd->fd, buf, bytes_remaining, offset); if (unlikely(bytes_written < 0)) { @@ -204,43 +201,6 @@ full_pwrite(struct filedes *fd, const void *buf, size_t count, off_t offset) return 0; } -/* Wrapper around writev() that keep retrying until all requested bytes have been - * written. - * - * Return values: - * WIMLIB_ERR_SUCCESS (0) - * WIMLIB_ERR_WRITE (errno set) - * */ -int -full_writev(struct filedes *fd, struct iovec *iov, int iovcnt) -{ - size_t total_bytes_written = 0; - while (iovcnt > 0) { - ssize_t bytes_written; - - bytes_written = writev(fd->fd, iov, iovcnt); - if (bytes_written < 0) { - if (errno == EINTR) - continue; - return WIMLIB_ERR_WRITE; - } - total_bytes_written += bytes_written; - while (bytes_written) { - if (bytes_written >= iov[0].iov_len) { - bytes_written -= iov[0].iov_len; - iov++; - iovcnt--; - } else { - iov[0].iov_base += bytes_written; - iov[0].iov_len -= bytes_written; - bytes_written = 0; - } - } - } - fd->offset += total_bytes_written; - return 0; -} - ssize_t raw_pread(struct filedes *fd, void *buf, size_t count, off_t offset) {