/* mkswap.c - Format swap device. * * Copyright 2009 Rob Landley <rob@landley.net> USE_MKSWAP(NEWTOY(mkswap, "<1>1", TOYFLAG_SBIN)) config MKSWAP bool "mkswap" default y help usage: mkswap DEVICE Sets up a Linux swap area on a device or file. */ #include "toys.h" void mkswap_main(void) { int fd = xopen(*toys.optargs, O_RDWR), pagesize = sysconf(_SC_PAGE_SIZE); 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)); }