From 52476716ad2bff9805e5749bf2c2a1f9d3512ec9 Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Sun, 18 Jan 2009 16:19:25 -0600 Subject: Add mkswap. --- toys/mkswap.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) create mode 100644 toys/mkswap.c (limited to 'toys') diff --git a/toys/mkswap.c b/toys/mkswap.c new file mode 100644 index 00000000..f902efeb --- /dev/null +++ b/toys/mkswap.c @@ -0,0 +1,42 @@ +/* vi: set sw=4 ts=4: + * + * mkswap.c - Format swap device. + * + * Copyright 2009 Rob Landley + * + * Not in SUSv3. + +USE_MKSWAP(NEWTOY(mkswap, "<1>2", TOYFLAG_SBIN)) + +config MKSWAP + bool "mkswap" + default y + help + usage: mkswap DEVICE + + Format a Linux v1 swap device. +*/ + +#include "toys.h" + +void mkswap_main(void) +{ + int fd = xopen(*toys.optargs, O_RDWR), pagesize = getpagesize(); + off_t len = fdlength(fd); + unsigned int pages = (len/pagesize)-1, *swap = (unsigned int *)toybuf; + + // Write header. Note that older kernel versions checked signature + // on disk (not in cache) during swapon, so sync after writing. + + swap[0] = 1; + swap[1] = pages; + xlseek(fd, 1024, SEEK_SET); + xwrite(fd, swap, 129*sizeof(unsigned int)); + xlseek(fd, pagesize-10, SEEK_SET); + xwrite(fd, "SWAPSPACE2", 10); + fsync(fd); + + if (CFG_TOYBOX_FREE) close(fd); + + printf("Swapspace size: %luk\n", pages*(unsigned long)(pagesize/1024)); +} -- cgit v1.2.3