diff options
| -rw-r--r-- | ChangeLog | 14 | ||||
| -rw-r--r-- | support/Makefile | 2 | ||||
| -rw-r--r-- | support/support.h | 5 | ||||
| -rw-r--r-- | support/support_copy_file_range.c | 143 | ||||
| -rw-r--r-- | support/test-container.c | 3 | ||||
| -rw-r--r-- | support/xcopy_file_range.c | 32 | ||||
| -rw-r--r-- | support/xunistd.h | 3 |
7 files changed, 200 insertions, 2 deletions
diff --git a/ChangeLog b/ChangeLog index 21d914141c..5288a7e519 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,17 @@ +2018-08-31 H.J. Lu <hongjiu.lu@intel.com> + + [BZ #23597] + * support/Makefile (libsupport-routines): Add + support_copy_file_range and xcopy_file_range. + * support/support.h: Include <sys/types.h>. + (support_copy_file_range): New prototype. + * support/support_copy_file_range.c: New file. Copied and + modified from io/copy_file_range-compat.c. + * support/test-container.c (copy_one_file): Call xcopy_file_rang + instead of copy_file_range. + * support/xcopy_file_range.c: New file. + * support/xunistd.h (xcopy_file_range): New prototype. + 2018-08-30 Carlos O'Donell <carlos@redhat.com> * elf/tst-dlopen-aout.c: Include support/xthread.h. Use diff --git a/support/Makefile b/support/Makefile index b528f538a6..545bfa2727 100644 --- a/support/Makefile +++ b/support/Makefile @@ -43,6 +43,7 @@ libsupport-routines = \ support_capture_subprocess \ support_capture_subprocess_check \ support_chroot \ + support_copy_file_range \ support_descriptor_supports_holes \ support_enter_mount_namespace \ support_enter_network_namespace \ @@ -74,6 +75,7 @@ libsupport-routines = \ xchroot \ xclose \ xconnect \ + xcopy_file_range \ xdlfcn \ xdup2 \ xfclose \ diff --git a/support/support.h b/support/support.h index c6ff4bafb4..d0e15bca1d 100644 --- a/support/support.h +++ b/support/support.h @@ -27,6 +27,8 @@ #include <sys/cdefs.h> /* For mode_t. */ #include <sys/stat.h> +/* For ssize_t and off64_t. */ +#include <sys/types.h> __BEGIN_DECLS @@ -94,6 +96,9 @@ extern const char support_install_prefix[]; /* Corresponds to the install's lib/ or lib64/ directory. */ extern const char support_libdir_prefix[]; +extern ssize_t support_copy_file_range (int, off64_t *, int, off64_t *, + size_t, unsigned int); + __END_DECLS #endif /* SUPPORT_H */ diff --git a/support/support_copy_file_range.c b/support/support_copy_file_range.c new file mode 100644 index 0000000000..9a1e39773e --- /dev/null +++ b/support/support_copy_file_range.c @@ -0,0 +1,143 @@ +/* Simplified copy_file_range with cross-device copy. + Copyright (C) 2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library 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. + + The GNU C Library 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 the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <fcntl.h> +#include <inttypes.h> +#include <limits.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <unistd.h> +#include <support/support.h> + +ssize_t +support_copy_file_range (int infd, __off64_t *pinoff, + int outfd, __off64_t *poutoff, + size_t length, unsigned int flags) +{ + if (flags != 0) + { + errno = EINVAL; + return -1; + } + + struct stat64 instat; + struct stat64 outstat; + if (fstat64 (infd, &instat) != 0 || fstat64 (outfd, &outstat) != 0) + return -1; + if (S_ISDIR (instat.st_mode) || S_ISDIR (outstat.st_mode)) + { + errno = EISDIR; + return -1; + } + if (!S_ISREG (instat.st_mode) || !S_ISREG (outstat.st_mode)) + { + /* We need a regular input file so that the we can seek + backwards in case of a write failure. */ + errno = EINVAL; + return -1; + } + + /* The output descriptor must not have O_APPEND set. */ + if (fcntl (outfd, F_GETFL) & O_APPEND) + { + errno = EBADF; + return -1; + } + + /* Avoid an overflow in the result. */ + if (length > SSIZE_MAX) + length = SSIZE_MAX; + + /* Main copying loop. The buffer size is arbitrary and is a + trade-off between stack size consumption, cache usage, and + amortization of system call overhead. */ + size_t copied = 0; + char buf[8192]; + while (length > 0) + { + size_t to_read = length; + if (to_read > sizeof (buf)) + to_read = sizeof (buf); + + /* Fill the buffer. */ + ssize_t read_count; + if (pinoff == NULL) + read_count = read (infd, buf, to_read); + else + read_count = pread64 (infd, buf, to_read, *pinoff); + if (read_count == 0) + /* End of file reached prematurely. */ + return copied; + if (read_count < 0) + { + if (copied > 0) + /* Report the number of bytes copied so far. */ + return copied; + return -1; + } + if (pinoff != NULL) + *pinoff += read_count; + + /* Write the buffer part which was read to the destination. */ + char *end = buf + read_count; + for (char *p = buf; p < end; ) + { + ssize_t write_count; + if (poutoff == NULL) + write_count = write (outfd, p, end - p); + else + write_count = pwrite64 (outfd, p, end - p, *poutoff); + if (write_count < 0) + { + /* Adjust the input read position to match what we have + written, so that the caller can pick up after the + error. */ + size_t written = p - buf; + /* NB: This needs to be signed so that we can form the + negative value below. */ + ssize_t overread = read_count - written; + if (pinoff == NULL) + { + if (overread > 0) + { + /* We are on an error recovery path, so we + cannot deal with failure here. */ + int save_errno = errno; + (void) lseek64 (infd, -overread, SEEK_CUR); + errno = save_errno; + } + } + else /* pinoff != NULL */ + *pinoff -= overread; + + if (copied + written > 0) + /* Report the number of bytes copied so far. */ + return copied + written; + return -1; + } + p += write_count; + if (poutoff != NULL) + *poutoff += write_count; + } /* Write loop. */ + + copied += read_count; + length -= read_count; + } + return copied; +} diff --git a/support/test-container.c b/support/test-container.c index 2e91bdf9ec..c56b53ed81 100644 --- a/support/test-container.c +++ b/support/test-container.c @@ -383,8 +383,7 @@ copy_one_file (const char *sname, const char *dname) if (dfd < 0) FAIL_EXIT1 ("unable to open %s for writing\n", dname); - if (copy_file_range (sfd, 0, dfd, 0, st.st_size, 0) != st.st_size) - FAIL_EXIT1 ("cannot copy file %s to %s\n", sname, dname); + xcopy_file_range (sfd, 0, dfd, 0, st.st_size, 0); xclose (sfd); xclose (dfd); diff --git a/support/xcopy_file_range.c b/support/xcopy_file_range.c new file mode 100644 index 0000000000..b3501a4d5e --- /dev/null +++ b/support/xcopy_file_range.c @@ -0,0 +1,32 @@ +/* copy_file_range with error checking. + Copyright (C) 2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library 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. + + The GNU C Library 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 the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <support/support.h> +#include <support/xunistd.h> +#include <support/check.h> + +ssize_t +xcopy_file_range (int infd, off64_t *pinoff, int outfd, off64_t *poutoff, + size_t length, unsigned int flags) +{ + ssize_t status = support_copy_file_range (infd, pinoff, outfd, + poutoff, length, flags); + if (status == -1) + FAIL_EXIT1 ("cannot copy file: %m\n"); + return status; +} diff --git a/support/xunistd.h b/support/xunistd.h index cdd4e8d92d..f99f362cb4 100644 --- a/support/xunistd.h +++ b/support/xunistd.h @@ -64,6 +64,9 @@ void *xmmap (void *addr, size_t length, int prot, int flags, int fd); void xmprotect (void *addr, size_t length, int prot); void xmunmap (void *addr, size_t length); +ssize_t xcopy_file_range(int fd_in, loff_t *off_in, int fd_out, + loff_t *off_out, size_t len, unsigned int flags); + __END_DECLS #endif /* SUPPORT_XUNISTD_H */ |