Add create_archive function

src/checksum.rs

@@ -3,6 +3,14 @@ use {
     std::io::{Read, Write},
 };
 
+#[derive(Clone, Copy, Debug)]
+pub enum Algorithm {
+    Md5,
+    Sha1,
+    Sha256,
+    Skip,
+}
+
 /// Optional checksumming for individual files
 #[derive(Debug)]
 pub enum Checksum {
@@ -20,7 +28,7 @@ pub enum Checksum {
 }
 
 impl Checksum {
-    pub fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
+    pub(crate) fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
         let mut buf = [0; 1];
         reader.read_exact(&mut buf)?;
         match buf[0] {
@@ -43,7 +51,7 @@ impl Checksum {
         }
     }
 
-    pub fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
+    pub(crate) fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
         match self {
             Self::Md5(sum) => {
                 writer.write_all(&[b'0'])?;

src/file.rs

@@ -18,7 +18,7 @@ pub struct File {
 }
 
 impl File {
-    pub fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
+    pub(crate) fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
         let mut len = [0; 8];
         reader.read_exact(&mut len)?;
         let len = u64::from_le_bytes(len);
@@ -77,7 +77,7 @@ impl File {
         }
     }
 
-    pub fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
+    pub(crate) fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
         writer.write_all(&self.len.to_be_bytes())?;
         Checksum::write(&self.checksum, writer)?;
         writer.write_all(&self.data)?;

src/filetype.rs

@@ -25,7 +25,7 @@ pub enum FileType {
 }
 
 impl FileType {
-    pub fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
+    pub(crate) fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
         let mut buf = [0; 1];
         reader.read_exact(&mut buf)?;
         match buf[0] {
@@ -67,7 +67,7 @@ impl FileType {
         }
     }
 
-    pub fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
+    pub(crate) fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
         match self {
             Self::Normal(f) => {
                 writer.write_all(&[0])?;

src/lib.rs

@@ -1,13 +1,30 @@
+#![doc = include_str!("../README.md")]
+use std::{fs, collections::HashMap, io::BufWriter, sync::Mutex};
+
 mod checksum;
 mod error;
 mod file;
 mod filetype;
-pub mod nix;
+pub(crate) mod nix;
 mod node;
 mod special;
 mod stream;
 
 pub use {
-    checksum::Checksum, error::Error, file::File, filetype::FileType, node::Node, special::Special,
+    checksum::{Algorithm, Checksum}, error::Error, file::File, filetype::FileType, node::Node, special::Special,
     stream::Stream,
 };
+
+pub fn create_archive(path: &str, files: Vec<&str>, algorithm: Algorithm) -> Result<(), Error> {
+    let fd = fs::OpenOptions::new()
+        .create(true)
+        .truncate(true)
+        .open(path)?;
+    let mut writer = BufWriter::new(fd);
+    let mut links = Mutex::new(HashMap::new());
+    for f in files.iter() {
+        let node = Node::from_path(f, algorithm, &mut links)?;
+        node.write(&mut writer)?;
+    }
+    Ok(())
+}

src/nix/mod.rs

@@ -1,9 +1,11 @@
 #![allow(clippy::must_use_candidate)]
+//! Low level Unix api functions
 use {
     crate::Error,
     std::{ffi::CString, io},
 };
 
+/// Get the effective user id of the current process
 pub fn geteuid() -> u32 {
     unsafe { libc::geteuid() }
 }

src/node.rs

@@ -1,5 +1,5 @@
 use {
-    crate::{nix, Checksum, Error, File, FileType, Special},
+    crate::{nix, Algorithm, Checksum, Error, File, FileType, Special},
     md5::{Digest, Md5},
     sha1::Sha1,
     sha2::Sha256,
@@ -121,7 +121,7 @@ impl Node {
     ///   avoid writing their data out more than once.
     pub fn from_path(
         path: &str,
-        checksum: Checksum,
+        algorithm: Algorithm,
         links: &Mutex<HashMap<u64, String>>,
     ) -> Result<Self, Error> {
         let name = String::from(path);
@@ -167,26 +167,26 @@ impl Node {
                     let mut len = meta.len();
                     let mut data = Vec::with_capacity(len.try_into()?);
                     len = reader.read_to_end(&mut data)?.try_into()?;
-                    let checksum = match checksum {
+                    let checksum = match algorithm {
-                        Checksum::Md5(mut cs) => {
+                        Algorithm::Md5 => {
                             let mut hasher = Md5::new();
                             hasher.update(&data);
-                            cs = hasher.finalize().into();
+                            let cs = hasher.finalize().into();
                             Checksum::Md5(cs)
                         }
-                        Checksum::Sha1(mut cs) => {
+                        Algorithm::Sha1 => {
                             let mut hasher = Sha1::new();
                             hasher.update(&data);
-                            cs = hasher.finalize().into();
+                            let cs = hasher.finalize().into();
                             Checksum::Sha1(cs)
                         }
-                        Checksum::Sha256(mut cs) => {
+                        Algorithm::Sha256 => {
                             let mut hasher = Sha256::new();
                             hasher.update(&data);
-                            cs = hasher.finalize().into();
+                            let cs = hasher.finalize().into();
                             Checksum::Sha256(cs)
                         }
-                        Checksum::Skip => checksum,
+                        Algorithm::Skip => Checksum::Skip,
                     };
                     break 'blk FileType::Normal(File {
                         len,
@@ -208,6 +208,7 @@ impl Node {
         })
     }
 
+    /// Recreates the original file on disk which this node represents
     pub fn extract(&self, prefix: Option<&str>) -> Result<(), Error> {
         let euid = nix::geteuid();
         let path = 'blk: {

src/special.rs

@@ -11,7 +11,7 @@ pub struct Special {
 }
 
 impl Special {
-    pub fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
+    pub(crate) fn read<T: Read>(reader: &mut T) -> Result<Self, Error> {
         let mut buf = [0; 8];
         reader.read_exact(&mut buf)?;
         let major: [u8; 4] = buf[..4].try_into()?;
@@ -21,7 +21,7 @@ impl Special {
         Ok(Self { major, minor })
     }
 
-    pub fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
+    pub(crate) fn write<T: Write>(&self, writer: &mut T) -> Result<(), Error> {
         writer.write_all(&self.major.to_le_bytes())?;
         writer.write_all(&self.minor.to_le_bytes())?;
         Ok(())