/* vi: set sw=4 ts=4: */ /* * sum -- checksum and count the blocks in a file * Like BSD sum or SysV sum -r, except like SysV sum if -s option is given. * * Copyright (C) 86, 89, 91, 1995-2002, 2004 Free Software Foundation, Inc. * Copyright (C) 2005 by Erik Andersen <andersen@codepoet.org> * Copyright (C) 2005 by Mike Frysinger <vapier@gentoo.org> * * Written by Kayvan Aghaiepour and David MacKenzie * Taken from coreutils and turned into a busybox applet by Mike Frysinger * * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. */ #include "libbb.h" enum { SUM_BSD, PRINT_NAME, SUM_SYSV }; /* BSD: calculate and print the rotated checksum and the size in 1K blocks The checksum varies depending on sizeof (int). */ /* SYSV: calculate and print the checksum and the size in 512-byte blocks */ /* Return 1 if successful. */ static unsigned sum_file(const char *file, unsigned type) { #define buf bb_common_bufsiz1 unsigned long long total_bytes = 0; int fd, r; /* The sum of all the input bytes, modulo (UINT_MAX + 1). */ unsigned s = 0; fd = open_or_warn_stdin(file); if (fd == -1) return 0; while (1) { size_t bytes_read = safe_read(fd, buf, BUFSIZ); if ((ssize_t)bytes_read <= 0) { r = (fd && close(fd) != 0); if (!bytes_read && !r) /* no error */ break; bb_perror_msg(file); return 0; } total_bytes += bytes_read; if (type >= SUM_SYSV) { do s += buf[--bytes_read]; while (bytes_read); } else { r = 0; do { s = (s >> 1) + ((s & 1) << 15); s += buf[r++]; s &= 0xffff; /* Keep it within bounds. */ } while (--bytes_read); } } if (type < PRINT_NAME) file = ""; if (type >= SUM_SYSV) { r = (s & 0xffff) + ((s & 0xffffffff) >> 16); s = (r & 0xffff) + (r >> 16); printf("%d %llu %s\n", s, (total_bytes + 511) / 512, file); } else printf("%05d %5llu %s\n", s, (total_bytes + 1023) / 1024, file); return 1; #undef buf } int sum_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int sum_main(int argc ATTRIBUTE_UNUSED, char **argv) { unsigned n; unsigned type = SUM_BSD; n = getopt32(argv, "sr"); argv += optind; if (n & 1) type = SUM_SYSV; /* give the bsd priority over sysv func */ if (n & 2) type = SUM_BSD; if (!argv[0]) { /* Do not print the name */ n = sum_file("-", type); } else { /* Need to print the name if either - more than one file given - doing sysv */ type += (argv[1] || type == SUM_SYSV); n = 1; do { n &= sum_file(*argv, type); } while (*++argv); } return !n; }