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-rw-r--r--util-linux/fallocate.c104
-rw-r--r--util-linux/fsfreeze.c2
2 files changed, 105 insertions, 1 deletions
diff --git a/util-linux/fallocate.c b/util-linux/fallocate.c
new file mode 100644
index 000000000..1cd851bde
--- /dev/null
+++ b/util-linux/fallocate.c
@@ -0,0 +1,104 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Copyright (C) 2017 Denys Vlasenko <vda.linux@googlemail.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
+ */
+
+//config:config FALLOCATE
+//config: bool "fallocate"
+//config: default y
+//config: help
+//config: Preallocate space for files.
+
+//applet:IF_FALLOCATE(APPLET(fallocate, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_FALLOCATE) += fallocate.o
+
+//usage:#define fallocate_trivial_usage
+//usage: "[-o OFS] -l LEN FILE"
+// fallocate [-c|-p|-z] [-n] [-o OFS] -l LEN FILE
+// fallocate -d [-o OFS] [-l LEN] FILE
+//usage:#define fallocate_full_usage "\n\n"
+//usage: "Preallocate space for FILE\n"
+// "\n -c Remove range"
+// "\n -p Make hole"
+// "\n -z Zero and allocate range"
+// "\n -d Convert zeros to holes"
+// "\n -n Keep size"
+//usage: "\n -o OFS Offset of range"
+//usage: "\n -l LEN Length of range"
+
+//Upstream options:
+//The options --collapse-range, --dig-holes, --punch-hole and --zero-range
+//are mutually exclusive.
+//-c, --collapse-range
+// Removes a byte range from a file, without leaving a hole. The byte range
+// to be collapsed starts at offset and continues for length bytes.
+// At the completion of the operation, the contents of the file starting
+// at the location offset+length will be appended at the location offset,
+// and the file will be length bytes smaller. The option --keep-size may
+// not be specified for the collapse-range operation.
+//-d, --dig-holes
+// Detect and dig holes. This makes the file sparse in-place, without using
+// extra disk space. The minimum size of the hole depends on filesystem I/O
+// block size (usually 4096 bytes). Also,
+//-l, --length length
+// Specifies the length of the range, in bytes.
+//-n, --keep-size
+// Do not modify the apparent length of the file. This may effectively
+// allocate blocks past EOF, which can be removed with a truncate.
+//-o, --offset offset
+// Specifies the beginning offset of the range, in bytes.
+//-p, --punch-hole
+// Deallocates space (i.e., creates a hole) in the byte range starting
+// at offset and continuing for length bytes. Within the specified range,
+// partial filesystem blocks are zeroed, and whole
+// filesystem blocks are removed from the file. After a successful call,
+// subsequent reads from this range will return zeroes. This option may not
+// be specified at the same time as the
+// --zero-range option. Also, when using this option, --keep-size is implied.
+//-z, --zero-range
+// Zeroes space in the byte range starting at offset and continuing for
+// length bytes. Within the specified range, blocks are preallocated for
+// the regions that span the holes in the file. After
+// a successful call, subsequent reads from this range will return zeroes.
+// Zeroing is done within the filesystem preferably by converting the range
+// into unwritten extents. This approach means that the specified range
+// will not be physically zeroed out on the device (except for partial
+// blocks at the either end of the range), and I/O is (otherwise) required
+// only to update metadata.
+// Option --keep-size can be specified to prevent file length modification.
+
+#include "libbb.h"
+
+int fallocate_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int fallocate_main(int argc UNUSED_PARAM, char **argv)
+{
+ const char *str_l;
+ const char *str_o = "0";
+ off_t ofs, len;
+ unsigned opts;
+ int fd;
+
+ /* exactly one non-option arg */
+ opt_complementary = "=1";
+ opts = getopt32(argv, "l:o:", &str_l, &str_o);
+ if (!(opts & 1))
+ bb_show_usage();
+
+ ofs = xatoull_sfx(str_o, kmg_i_suffixes);
+ len = xatoull_sfx(str_l, kmg_i_suffixes);
+
+ argv += optind;
+ fd = xopen3(*argv, O_RDWR | O_CREAT, 0666);
+
+ /* posix_fallocate has unusual method of returning error */
+ /* maybe use Linux-specific fallocate(int fd, int mode, off_t offset, off_t len) instead? */
+ if ((errno = posix_fallocate(fd, ofs, len)) != 0)
+ bb_perror_msg_and_die("fallocate '%s'", *argv);
+
+ /* util-linux also performs fsync(fd); */
+
+ return EXIT_SUCCESS;
+}
diff --git a/util-linux/fsfreeze.c b/util-linux/fsfreeze.c
index fb1ebdc1e..70dec24ec 100644
--- a/util-linux/fsfreeze.c
+++ b/util-linux/fsfreeze.c
@@ -13,7 +13,7 @@
//config: help
//config: Halt new accesses and flush writes on a mounted filesystem.
-//applet:IF_FSFREEZE(APPLET(fsfreeze, BB_DIR_SBIN, BB_SUID_DROP))
+//applet:IF_FSFREEZE(APPLET(fsfreeze, BB_DIR_USR_SBIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_FSFREEZE) += fsfreeze.o