Hi Paul, Thanks for digging up that documentation and for the patch. I've applied it and added a test case.
Paul Eggert <[EMAIL PROTECTED]> wrote: >> From: Jim Meyering <[EMAIL PROTECTED]> >> Date: Sun, 28 Oct 2001 01:40:29 +0200 > >> [on Solaris 5.8] >> $ perl -e 'print chr(255) x 16843010'|/bin/sum >> 254 32897 >> >> I think that first number should be 255. > > No, 254 is correct. The problem is that the GNU code is reducing at > the wrong place; it should reduce at the end, not after every input byte. > The NetBSD documentation makes this pretty clear; e.g. see > <http://www.tac.eu.org/cgi-bin/man-cgi?sum+1> > > Here is a patch, which cleans up a few other minor glitches > that I noticed in the neighborhood (sorry, I couldn't resist :-). > > 2001-10-27 Paul Eggert <[EMAIL PROTECTED]> > > * src/sum.c: Include human.h. > > (ROTATE_RIGHT): Remove; it was slow and the comment was > misleading anyway. > > (bsd_sum_file): Avoid unsigned and long when they're not needed. > Compute total input bytes as uintmax_t, not long, so that the > code works even with files whose size does not fit in 'long'. > (sysv_sum_file): Likewise. > > (sysv_sum_file): Do not reduce checksum until the end; this is > what System V does. > > =================================================================== > RCS file: src/sum.c,v > retrieving revision 2.0.16.0 > retrieving revision 2.0.16.1 > diff -pu -r2.0.16.0 -r2.0.16.1 > --- src/sum.c 2001/08/13 10:29:59 2.0.16.0 > +++ src/sum.c 2001/10/28 06:21:15 2.0.16.1 > @@ -27,6 +27,7 @@ > #include "system.h" > #include "closeout.h" > #include "error.h" > +#include "human.h" > #include "safe-read.h" > > /* The official name of this program (e.g., no `g' prefix). */ > @@ -40,9 +41,6 @@ char *program_name; > /* Nonzero if any of the files read were the standard input. */ > static int have_read_stdin; > > -/* Right-rotate 32-bit integer variable C. */ > -#define ROTATE_RIGHT(c) if ((c) & 01) (c) = ((c) >>1) + 0x8000; else (c) >>= 1; > - > static struct option const longopts[] = > { > {"sysv", no_argument, NULL, 's'}, > @@ -88,9 +86,10 @@ static int > bsd_sum_file (const char *file, int print_name) > { > register FILE *fp; > - register unsigned long checksum = 0; /* The checksum mod 2^16. */ > - register long total_bytes = 0; /* The number of bytes. */ > + register int checksum = 0; /* The checksum mod 2^16. */ > + register uintmax_t total_bytes = 0; /* The number of bytes. */ > register int ch; /* Each character read. */ > + char hbuf[LONGEST_HUMAN_READABLE + 1]; > > if (STREQ (file, "-")) > { > @@ -112,7 +111,7 @@ bsd_sum_file (const char *file, int prin > while ((ch = getc (fp)) != EOF) > { > total_bytes++; > - ROTATE_RIGHT (checksum); > + checksum = (checksum >> 1) + ((checksum & 1) << 15); > checksum += ch; > checksum &= 0xffff; /* Keep it within bounds. */ > } > @@ -131,7 +130,8 @@ bsd_sum_file (const char *file, int prin > return -1; > } > > - printf ("%05lu %5ld", checksum, (total_bytes + 1024 - 1) / 1024); > + printf ("%05d %5s", checksum, > + human_readable_inexact (total_bytes, hbuf, 1, 1024, human_ceiling)); > if (print_name > 1) > printf (" %s", file); > putchar ('\n'); > @@ -150,8 +150,13 @@ sysv_sum_file (const char *file, int pri > int fd; > unsigned char buf[8192]; > register int bytes_read; > - register unsigned long checksum = 0; > - long total_bytes = 0; > + uintmax_t total_bytes = 0; > + char hbuf[LONGEST_HUMAN_READABLE + 1]; > + int r; > + int checksum; > + > + /* The sum of all the input bytes, modulo (UINT_MAX + 1). */ > + register unsigned int s = 0; > > if (STREQ (file, "-")) > { > @@ -175,10 +180,7 @@ sysv_sum_file (const char *file, int pri > register int i; > > for (i = 0; i < bytes_read; i++) > - checksum += buf[i]; > - /* Reduce checksum mod 0xffff, to avoid overflow. */ > - checksum = (checksum & 0xffff) + (checksum >> 16); > - > + s += buf[i]; > total_bytes += bytes_read; > } > > @@ -196,7 +198,11 @@ sysv_sum_file (const char *file, int pri > return -1; > } > > - printf ("%lu %ld", checksum % 0xffff, (total_bytes + 512 - 1) / 512); > + r = (s & 0xffff) + ((s & 0xffffffff) >> 16); > + checksum = (r & 0xffff) + (r >> 16); > + > + printf ("%d %s", checksum, > + human_readable_inexact (total_bytes, hbuf, 1, 512, human_ceiling)); > if (print_name) > printf (" %s", file); > putchar ('\n'); _______________________________________________ Bug-textutils mailing list [EMAIL PROTECTED] http://mail.gnu.org/mailman/listinfo/bug-textutils
