1 files changed, 70 insertions, 47 deletions

diff --git a/libbb/human_readable.c b/libbb/human_readable.c
index 2cb887563..548712c75 100644
--- a/libbb/human_readable.c
+++ b/libbb/human_readable.c
@@ -1,66 +1,89 @@
-/* vi: set sw=4 ts=4: */
 /*
- * make_human_readable_str
+ * June 30, 2001                 Manuel Novoa III
  *
- * Copyright (C) 1999-2001 Erik Andersen <andersee@debian.org>
+ * All-integer version (hey, not everyone has floating point) of
+ * make_human_readable_str, modified from similar code I had written
+ * for busybox several months ago.
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * Notes:
+ *   1) I'm using an unsigned long long to hold the product size * block_size,
+ *      as df (which calls this routine) could request a representation of a
+ *      partition size in bytes > max of unsigned long.  If long longs aren't
+ *      available, it would be possible to do what's needed using polynomial
+ *      representations (say, powers of 1024) and manipulating coefficients.
+ *      The base ten "bytes" output could be handled similarly.
  *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
+ *   2) The output of "ls -sh" can be misaligned because this routine always
+ *      outputs a decimal point and a tenths digit when display_unit != 0.
+ *      Hence, it isn't uncommon for the returned string to have a length
+ *      of 5 or 6 instead of <= 4 (as assumed).
  *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *      It might be nice to add a flag to indicate no decimal digits in
+ *      that case.  This could be either an additional parameter, or a
+ *      special value of display_unit.  Such a flag would also be nice for du.
+ *
+ *      Some code to omit the decimal point and tenths digit is sketched out
+ *      and "#if 0"'d below.
  */
 
 #include <stdio.h>
 #include "libbb.h"
 
-
-
 const char *make_human_readable_str(unsigned long size, 
-                unsigned long block_size, unsigned long display_unit)
+                                                                        unsigned long block_size,
+                                                                        unsigned long display_unit)
 {
-        static char str[10] = "\0";
-        static const char strings[] = { 0, 'k', 'M', 'G', 'T', 0 };
+        /* The code will adjust for additional (appended) units. */
+        static const char zero_and_units[] = { '0', 0, 'k', 'M', 'G', 'T' };
+        static const char fmt[] = "%Lu";
+        static const char fmt_tenths[] = "%Lu.%d%c";
 
-        if(size == 0 || block_size == 0)
-                return("0");
+        static char str[21];            /* Sufficient for 64 bit unsigned integers. */
         
-        if(display_unit) {
-                snprintf(str, 9, "%ld", (size/display_unit)*block_size);
+        unsigned long long val;
+        int frac;
+        const char *u;
+        const char *f;
+
+        u = zero_and_units;
+        f = fmt;
+        frac = 0;
+
+        val = ((unsigned long long) size) * block_size;
+        if (val == 0) {
+                return u;
+        }
+
+        if (display_unit) {
+                val += display_unit/2;  /* Deal with rounding. */
+                val /= display_unit;    /* Don't combine with the line above!!! */
         } else {
-                /* Ok, looks like they want us to autoscale */
-                int i=0;
-                unsigned long divisor = 1;
-                long double result = size*block_size;
-                for(i=0; i <= 4; i++) {
-                        divisor<<=10;
-                        if (result <= divisor) {
-                                divisor>>=10;
-                                break;
+                ++u;
+                while ((val >= KILOBYTE)
+                           && (u < zero_and_units + sizeof(zero_and_units) - 1)) {
+                        f = fmt_tenths;
+                        ++u;
+                        frac = ((((int)(val % KILOBYTE)) * 10) + (KILOBYTE/2)) / KILOBYTE;
+                        val /= KILOBYTE;
+                }
+                if (frac >= 10) {               /* We need to round up here. */
+                        ++val;
+                        frac = 0;
+                }
+#if 0
+                /* Sample code to omit decimal point and tenths digit. */
+                if ( /* no_tenths */ 1 ) {
+                        if ( frac >= 5 ) {
+                                ++val;
                         }
+                        f = "%Lu%*c" /* fmt_no_tenths */ ;
+                        frac = 1;
                 }
-                result/=divisor;
-                if (result > 10)
-                        snprintf(str, 9, "%.0Lf%c", result, strings[i]);
-                else
-                        snprintf(str, 9, "%.1Lf%c", result, strings[i]);
+#endif
         }
-        return(str);
-}
 
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+        /* If f==fmt then 'frac' and 'u' are ignored. */
+        snprintf(str, sizeof(str), f, val, frac, *u);
+
+        return str;
+}