integer llBase64ToInteger(string base64str)

Converts a string containing an integer in Base64 representation to integer. Base64 is a fairly compact way to store any arbitrary 32-bit integer in a string, especially if the numbers can usually be big.

A string expressed in Base64 that represents the four bytes of a 32-bit integer.

The integer that the string represents, or zero if the string is more than 8 characters long.

• Strings with more than 8 characters cause the output to be 0.
• Padding is ignored; parsing proceeds until the first non-Base64 character is found.
• The implementation converts from Base64 to a string of bytes, and appends a null byte at the end. If the result has less than four bytes, garbage bytes will result.
• The bytes in the binary form of the Base64 string are always interpreted in big endian order (most-significant byte first). Extra non-zero trailing bits in the last Base64 digit are accepted and ignored. Incomplete bytes are not output, e.g. a string with one single character acts as an empty string.

integer i;

i = llBase64ToInteger("ABCDEF=="); // sets i to 1082128
// (A = 000000, B = 000001, C = 000010, ... so the binary
// number is 00000000000100001000011100010000 which
// in decimal is 1082128; note some bits of the binary
// representation of F are truncated)

i = llBase64ToInteger("ABCDEF"); // same as above

i = llBase64ToInteger("ABCDEA"); // same as above

i = llBase64ToInteger(""); // sets i to some number between 0 and 16777215
// (the appended 0 goes to the most significant byte
// and the rest are filled with garbage)

• llIntegerToBase64 encodes an integer in the Base64 format that this function decodes.
• llBase64ToString and llStringToBase64 convert to/from a UTF-8 encoded string instead of integer.
• llXorBase64 calculates the bitwise XOR of corresponding bytes represented by two Base64 strings, byte by byte.