From: Pekka Pessi <[email protected]> Issue fsync() system call on a file to ensure its buffers are synchronized with the backing storage.
Signed-off-by: Alexander Shishkin <[email protected]> --- coreutils/Config.in | 6 ++++++ coreutils/Kbuild | 1 + coreutils/fsync.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ include/applets.h | 1 + include/usage.h | 7 +++++++ 5 files changed, 60 insertions(+), 0 deletions(-) create mode 100644 coreutils/fsync.c diff --git a/coreutils/Config.in b/coreutils/Config.in index b047ce5..88642d7 100644 --- a/coreutils/Config.in +++ b/coreutils/Config.in @@ -249,6 +249,12 @@ config FOLD help Wrap text to fit a specific width. +config FSYNC + bool "fsync" + default n + help + fsync is used to flush file-related cached blocks to disk. + config HEAD bool "head" default n diff --git a/coreutils/Kbuild b/coreutils/Kbuild index 57100a9..4d6bde7 100644 --- a/coreutils/Kbuild +++ b/coreutils/Kbuild @@ -36,6 +36,7 @@ lib-$(CONFIG_EXPR) += expr.o lib-$(CONFIG_EXPAND) += expand.o lib-$(CONFIG_FALSE) += false.o lib-$(CONFIG_FOLD) += fold.o +lib-$(CONFIG_FSYNC) += fsync.o lib-$(CONFIG_HEAD) += head.o lib-$(CONFIG_HOSTID) += hostid.o lib-$(CONFIG_ID) += id.o diff --git a/coreutils/fsync.c b/coreutils/fsync.c new file mode 100644 index 0000000..b3a4af1 --- /dev/null +++ b/coreutils/fsync.c @@ -0,0 +1,45 @@ +/* vi: set sw=4 ts=4: */ +/* + * Mini fsync implementation for busybox + * + * Copyright (C) 2008 Nokia Corporation. All rights reserved. + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +#include "libbb.h" + +/* This is a NOFORK applet. Be very careful! */ + +int fsync_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int fsync_main(int argc, char **argv) +{ + int status = EXIT_SUCCESS; + int flags; + int fd; + char *path; + + flags = getopt32(argv, "d"); /* fdatasync */ + argv += optind; + + if (!*argv) { + bb_show_usage(); + } + + for (path = *argv++; path; path = *argv++) { + fd = open3_or_warn(path, O_NOATIME | O_NOCTTY | O_RDONLY, 0); + + if (fd == -1) { + status = EXIT_FAILURE; + continue; + } + + if ((flags ? fdatasync(fd) : fsync(fd)) == -1) { + bb_simple_perror_msg(path); + } + + close(fd); + } + + return status; +} diff --git a/include/applets.h b/include/applets.h index 5fbb346..9296160 100644 --- a/include/applets.h +++ b/include/applets.h @@ -165,6 +165,7 @@ IF_FSCK(APPLET(fsck, _BB_DIR_SBIN, _BB_SUID_NEVER)) //IF_E2FSCK(APPLET_ODDNAME(fsck.ext2, e2fsck, _BB_DIR_SBIN, _BB_SUID_NEVER, fsck_ext2)) //IF_E2FSCK(APPLET_ODDNAME(fsck.ext3, e2fsck, _BB_DIR_SBIN, _BB_SUID_NEVER, fsck_ext3)) IF_FSCK_MINIX(APPLET_ODDNAME(fsck.minix, fsck_minix, _BB_DIR_SBIN, _BB_SUID_NEVER, fsck_minix)) +IF_FSYNC(APPLET_NOFORK(fsync, fsync, _BB_DIR_BIN, _BB_SUID_NEVER, fsync)) IF_FTPD(APPLET(ftpd, _BB_DIR_USR_SBIN, _BB_SUID_NEVER)) IF_FTPGET(APPLET_ODDNAME(ftpget, ftpgetput, _BB_DIR_USR_BIN, _BB_SUID_NEVER, ftpget)) IF_FTPPUT(APPLET_ODDNAME(ftpput, ftpgetput, _BB_DIR_USR_BIN, _BB_SUID_NEVER, ftpput)) diff --git a/include/usage.h b/include/usage.h index e606925..3ea9a3d 100644 --- a/include/usage.h +++ b/include/usage.h @@ -4208,6 +4208,13 @@ #define sync_full_usage "\n\n" \ "Write all buffered filesystem blocks to disk" +#define fsync_trivial_usage \ + "[OPTION]... FILE..." +#define fsync_full_usage \ + "Write files' buffered blocks to disk\n" \ + "\nOptions:" \ + "\n -d Avoid syncing metadata (like access time)" + #define sysctl_trivial_usage \ "[OPTIONS]... [VALUE]..." #define sysctl_full_usage "\n\n" \ -- 1.6.3.1 _______________________________________________ busybox mailing list [email protected] http://lists.busybox.net/mailman/listinfo/busybox
