Struct YcdFileUtil 

pub struct YcdFileUtil;

Implementations

impl YcdFileUtil

pub fn get_header_size<P: AsRef<Path>>(file_name: P) -> Result<i32>

pub fn get_ycd_header<P: AsRef<Path>>( file_name: P, ) -> Result<HashMap<YcdHeaderInfoElem, String>>

pub fn read_digits<P: AsRef<Path>>( files: &[P], one_based_start_position: usize, length: usize, ) -> Result<String>

Read exactly length decimal digits of Pi starting at 1-based position one_based_start_position from the concatenation of the given YCD files.

Arguments

• files — An ordered, contiguous slice of YCD file paths (BlockID order). The first file need not have BlockID 0; absolute positions are derived from each file’s header.
• one_based_start_position — 1-based index of the first digit to return. Position 1 is the first decimal digit (the digit immediately after “3.”). The integer part, sign, and decimal point are never included.
• length — Number of digits to return. The result string is exactly length bytes of ASCII digits.

Returns

A String containing exactly length ASCII decimal digits on success.

Errors

Condition	io::ErrorKind
Empty file list, position 0, or length 0	InvalidInput
Start position out of range, or end exceeds range	InvalidInput
Gap, duplicate, or reversed files in list	InvalidInput
Invalid header, non-base-10, or corrupt compressed value	InvalidData
Position, offset, or end calculation overflow	InvalidData
File does not exist	NotFound
Payload truncated within logical range	UnexpectedEof
Output string pre-allocation failure	Other

Notes

• Files with TotalDigits == 0 are treated as having exactly Blocksize digits. A “shortened” final file (where the actual payload is smaller than Blocksize) cannot be detected via the header alone; payload truncation within the logical range is reported as UnexpectedEof.
• The entire file list is validated before any I/O on the payload begins.
• Only the compressed blocks that cover the requested range are decoded; no byte before the target block is read.
• A large length requires the same amount of heap memory for the result.