[01/11] support: Add support_copy_file
Commit Message
---
support/Makefile | 1 +
support/support.h | 5 +++++
support/support_copy_file.c | 43 +++++++++++++++++++++++++++++++++++++
3 files changed, 49 insertions(+)
create mode 100644 support/support_copy_file.c
Comments
LGTM with a couple nits below.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
On 09/11/2020 15:40, Florian Weimer via Libc-alpha wrote:
> ---
> support/Makefile | 1 +
> support/support.h | 5 +++++
> support/support_copy_file.c | 43 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 49 insertions(+)
> create mode 100644 support/support_copy_file.c
>
> diff --git a/support/Makefile b/support/Makefile
> index 4154863511..f5f59bf8d2 100644
> --- a/support/Makefile
> +++ b/support/Makefile
> @@ -46,6 +46,7 @@ libsupport-routines = \
> support_capture_subprocess \
> support_capture_subprocess_check \
> support_chroot \
> + support_copy_file \
> support_copy_file_range \
> support_descriptor_supports_holes \
> support_descriptors \
> diff --git a/support/support.h b/support/support.h
> index 905b5a76d8..abda3a69f1 100644
> --- a/support/support.h
> +++ b/support/support.h
> @@ -119,6 +119,11 @@ extern const char support_install_rootsbindir[];
> /* Corresponds to the install's compiled locale directory. */
> extern const char support_complocaledir_prefix[];
>
> +/* Copies the file at the path FROM to TO. If TO does not exist, it
> + is created. If TO is a regular file, it is truncated before
> + copying. The file mode is copied, but the permissions are not. */
> +extern void support_copy_file (const char *from, const char *to);
> +
> extern ssize_t support_copy_file_range (int, off64_t *, int, off64_t *,
> size_t, unsigned int);
>
Ok.
> diff --git a/support/support_copy_file.c b/support/support_copy_file.c
> new file mode 100644
> index 0000000000..bf8f83803a
> --- /dev/null
> +++ b/support/support_copy_file.c
> @@ -0,0 +1,43 @@
> +/* Copy a file from one path to another.
> + Copyright (C) 2020 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
> + <https://www.gnu.org/licenses/>. */
> +
> +#include <fcntl.h>
> +#include <support/check.h>
> +#include <support/support.h>
> +#include <support/xunistd.h>
> +
> +void
> +support_copy_file (const char *from, const char *to)
> +{
> + struct stat64 st;
> + xstat (from, &st);
> + int fd_from = xopen (from, O_RDONLY, 0);
> + mode_t mode = st.st_mode & 0777;
> + int fd_to = xopen (to, O_WRONLY | O_TRUNC | O_CREAT, mode);
> + ssize_t ret = support_copy_file_range (fd_from, NULL, fd_to, NULL,
> + st.st_size, 0);
> + if (ret < 0)
> + FAIL_EXIT1 ("copying from \"%s\" to \"%s\": %m", from, to);
> + if (ret != st.st_size)
> + FAIL_EXIT1 ("copying from \"%s\" to \"%s\": only %zd of %llu bytes copied",
This line seems too long.
> + from, to, ret, (unsigned long long int) st.st_size);
> + if (fchmod (fd_to, mode) < 0)
> + FAIL_EXIT1 ("fchmod on %s: %m", to);
Maybe put 'to' within quotations as well?
> + xclose (fd_to);
> + xclose (fd_from);
> +}
>
* Adhemerval Zanella via Libc-alpha:
>> + if (ret != st.st_size)
>> + FAIL_EXIT1 ("copying from \"%s\" to \"%s\": only %zd of %llu bytes copied",
>
> This line seems too long.
It's 79 characters long, which is the maximum according to:
<https://sourceware.org/glibc/wiki/Style_and_Conventions#A79-Column_Lines>
>> + from, to, ret, (unsigned long long int) st.st_size);
>> + if (fchmod (fd_to, mode) < 0)
>> + FAIL_EXIT1 ("fchmod on %s: %m", to);
>
> Maybe put 'to' within quotations as well?
Thanks, fixed. Will push if it still builds.
Florian
@@ -46,6 +46,7 @@ libsupport-routines = \
support_capture_subprocess \
support_capture_subprocess_check \
support_chroot \
+ support_copy_file \
support_copy_file_range \
support_descriptor_supports_holes \
support_descriptors \
@@ -119,6 +119,11 @@ extern const char support_install_rootsbindir[];
/* Corresponds to the install's compiled locale directory. */
extern const char support_complocaledir_prefix[];
+/* Copies the file at the path FROM to TO. If TO does not exist, it
+ is created. If TO is a regular file, it is truncated before
+ copying. The file mode is copied, but the permissions are not. */
+extern void support_copy_file (const char *from, const char *to);
+
extern ssize_t support_copy_file_range (int, off64_t *, int, off64_t *,
size_t, unsigned int);
new file mode 100644
@@ -0,0 +1,43 @@
+/* Copy a file from one path to another.
+ Copyright (C) 2020 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <fcntl.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xunistd.h>
+
+void
+support_copy_file (const char *from, const char *to)
+{
+ struct stat64 st;
+ xstat (from, &st);
+ int fd_from = xopen (from, O_RDONLY, 0);
+ mode_t mode = st.st_mode & 0777;
+ int fd_to = xopen (to, O_WRONLY | O_TRUNC | O_CREAT, mode);
+ ssize_t ret = support_copy_file_range (fd_from, NULL, fd_to, NULL,
+ st.st_size, 0);
+ if (ret < 0)
+ FAIL_EXIT1 ("copying from \"%s\" to \"%s\": %m", from, to);
+ if (ret != st.st_size)
+ FAIL_EXIT1 ("copying from \"%s\" to \"%s\": only %zd of %llu bytes copied",
+ from, to, ret, (unsigned long long int) st.st_size);
+ if (fchmod (fd_to, mode) < 0)
+ FAIL_EXIT1 ("fchmod on %s: %m", to);
+ xclose (fd_to);
+ xclose (fd_from);
+}