diff options
Diffstat (limited to 'libgcobol/stringbin.cc')
| -rw-r--r-- | libgcobol/stringbin.cc | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/libgcobol/stringbin.cc b/libgcobol/stringbin.cc index d35ea82..2cc229e 100644 --- a/libgcobol/stringbin.cc +++ b/libgcobol/stringbin.cc @@ -328,3 +328,150 @@ __gg__binary_to_string_internal(char *result, int digits, __int128 value) return retval; } + +static +void +packed_from_combined(COMBINED &combined) + { + /* The combined.value must be positive at this point. + + The combined.run value has to be the number of places needed to hold + combined.value. The proper calculation is (digits+1)/2. + + For a signable value, the caller had to multiple the original value by + ten to create room on the right for the sign nybble. */ + + static const unsigned char bin2pd[100] = + { + 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, + 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, + 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, + 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, + 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, + 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, + 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, + 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, + 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, + 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, + } ; + + COMBINED left; + COMBINED right; + + switch(combined.run) + { + case 1: + // We know that val8 has two digits. + combined_string[combined.start] = bin2pd[combined.val8]; + break; + + case 2: + // We know that val16 has four digits. + combined_string[combined.start ] = bin2pd[combined.val16/100]; + combined_string[combined.start+1] = bin2pd[combined.val16%100]; + break; + + case 3: + case 4: + // We know that val32 can hold up to eight digits. Break it in half. + left.start = combined.start; + left.run = combined.run - 2; + left.val16 = combined.val32 / 10000; + + right.start = combined.start+left.run; + right.run = 2; + right.val16 = combined.val32 % 10000; + + packed_from_combined(left); + packed_from_combined(right); + break; + + case 5: + case 6: + case 7: + case 8: + // We know that val64 is holding up to 18 digits. Break it into two + // eight-digit places that can each go into a val23 + left.start = combined.start; + left.run = combined.run - 4; + left.val32 = combined.val64 / 100000000; + + right.start = combined.start+left.run; + right.run = 4; + right.val32 = combined.val64 % 100000000; + + packed_from_combined(left); + packed_from_combined(right); + break; + + case 9: + // We know that val64 is holding 17 or 18 digits. Break off the + // bottom eight. + left.start = combined.start; + left.run = combined.run - 4; + left.val64 = combined.val64 / 100000000; + + right.start = combined.start+left.run; + right.run = 4; + right.val32 = combined.val64 % 100000000; + + packed_from_combined(left); + packed_from_combined(right); + break; + + case 10: + case 11: + case 12: + case 13: + case 14: + case 15: + case 16: + case 17: + case 18: + // We know that val64 is holding between 18 and 36 digits. Break it + // two val64: + + left.start = combined.start; + left.run = combined.run - 9; + left.val64 = combined.val128 / 1000000000000000000ULL; + + right.start = combined.start+left.run; + right.run = 9; + right.val64 = combined.val128 % 1000000000000000000ULL; + + packed_from_combined(left); + packed_from_combined(right); + break; + + default: + // For twenty or more digits we peel eighteen digits at a time off the + // right side: + left.start = combined.start; + left.run = combined.run - 9; + left.val128 = combined.val128 / 1000000000000000000ULL; + + right.start = combined.start+left.run; + right.run = 9; + right.val64 = combined.val128 % 1000000000000000000ULL; + + packed_from_combined(left); + packed_from_combined(right); + break; + } + } + +extern "C" +void +__gg__binary_to_packed( unsigned char *result, + int digits, + __int128 value) + { + size_t length = (digits+1)/2; + + COMBINED combined; + combined.start = 0; + combined.run = length; + combined.val128 = value; + packed_from_combined(combined); + memcpy(result, combined_string, length); + } |