Struct cpio::newc::Reader

pub struct Reader<R: Read> { /* private fields */ }

Reads one entry header/data from an archive.

Implementations

impl<R: Read> Reader<R>

pub fn new(inner: R) -> Result<Reader<R>>

Parses metadata for the next entry in an archive, and returns a reader that will yield the entry data.

Examples found in repository

examples/listcpio.rs (line 9)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }
        println!(
            "{} ({} bytes)",
            reader.entry().name(),
            reader.entry().file_size()
        );
        file = reader.finish().unwrap();
    }
}

examples/extractcpio.rs (line 11)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let filename = std::env::args().nth(2).unwrap();
    let output = std::env::args().nth(3).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }

        if filename == reader.entry().name() {
            println!(
                "{} ({} bytes)",
                reader.entry().name(),
                reader.entry().file_size()
            );

            let out = std::fs::File::create(&output).unwrap();
            file = reader.to_writer(out).unwrap();
        } else {
            file = reader.skip().unwrap();
        }
    }
}

pub fn entry(&self) -> &Entry

Returns the metadata for this entry.

Examples found in repository

examples/listcpio.rs (line 10)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }
        println!(
            "{} ({} bytes)",
            reader.entry().name(),
            reader.entry().file_size()
        );
        file = reader.finish().unwrap();
    }
}

examples/extractcpio.rs (line 12)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let filename = std::env::args().nth(2).unwrap();
    let output = std::env::args().nth(3).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }

        if filename == reader.entry().name() {
            println!(
                "{} ({} bytes)",
                reader.entry().name(),
                reader.entry().file_size()
            );

            let out = std::fs::File::create(&output).unwrap();
            file = reader.to_writer(out).unwrap();
        } else {
            file = reader.skip().unwrap();
        }
    }
}

pub fn finish(self) -> Result<R>

Finishes reading this entry and returns the underlying reader in a position ready to read the next entry (if any).

Examples found in repository

examples/listcpio.rs (line 18)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }
        println!(
            "{} ({} bytes)",
            reader.entry().name(),
            reader.entry().file_size()
        );
        file = reader.finish().unwrap();
    }
}

pub fn to_writer<W: Write>(self, writer: W) -> Result<R>

Write the contents of the entry out to the writer using io::copy, taking advantage of any platform-specific behavior to effeciently copy data that io::copy can use. If any of the file data has already been read through the Read interface, this will copy the remaining data in the entry.

Examples found in repository

examples/extractcpio.rs (line 24)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let filename = std::env::args().nth(2).unwrap();
    let output = std::env::args().nth(3).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }

        if filename == reader.entry().name() {
            println!(
                "{} ({} bytes)",
                reader.entry().name(),
                reader.entry().file_size()
            );

            let out = std::fs::File::create(&output).unwrap();
            file = reader.to_writer(out).unwrap();
        } else {
            file = reader.skip().unwrap();
        }
    }
}

impl<R: Read + Seek> Reader<R>

pub fn offset(&mut self) -> Result<u64>

Returns the offset within inner, which can be useful for efficient io::copy()/copy_file_range() of file data.

pub fn skip(self) -> Result<R>

Skip past all remaining file data in this entry, returning the underlying reader in a position ready to read the next entry (if any).

Examples found in repository

examples/extractcpio.rs (line 26)

fn main() {
    let path = std::env::args().nth(1).unwrap();
    let filename = std::env::args().nth(2).unwrap();
    let output = std::env::args().nth(3).unwrap();
    let mut file = std::fs::File::open(path).unwrap();
    loop {
        let reader = cpio::NewcReader::new(file).unwrap();
        if reader.entry().is_trailer() {
            break;
        }

        if filename == reader.entry().name() {
            println!(
                "{} ({} bytes)",
                reader.entry().name(),
                reader.entry().file_size()
            );

            let out = std::fs::File::create(&output).unwrap();
            file = reader.to_writer(out).unwrap();
        } else {
            file = reader.skip().unwrap();
        }
    }
}

Trait Implementations

impl<R: Read> Read for Reader<R>

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Read all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Read all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Read the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact(&mut self, cursor: BorrowedCursor<'_>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Read the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adaptor for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.