| /* |

| * June 30, 2001 Manuel Novoa III |

| * |

| * 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. |

| * |

| * 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. |

| * |

| * 2) 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. |

| * |

| * 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 long size, |

| unsigned long block_size, unsigned long display_unit) |

| { |

| /* 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"; |

| |

| static char str[21]; /* Sufficient for 64 bit unsigned integers. */ |

| |

| unsigned long long val; |

| int frac; |

| const char *u; |

| const char *f; |

| |

| u = zero_and_units; |

| f = fmt; |

| frac = 0; |

| |

| val = 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 { |

| ++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; |

| } |

| #endif |

| } |

| |

| /* If f==fmt then 'frac' and 'u' are ignored. */ |

| snprintf(str, sizeof(str), f, val, frac, *u); |

| |

| return str; |

| } |