feat: further work on new repo & package implementation

libarchive/src/write/file.rs

@@ -2,10 +2,12 @@ use super::WriteEntry;
 use crate::error::ArchiveError;
 use crate::Entry;
 use crate::Handle;
+use core::ffi::c_void;
 use libarchive3_sys::ffi;
 use std::fs;
 use std::io;
 use std::io::Read;
+use std::io::Write;
 use std::path::Path;
 
 pub struct FileWriter {
@@ -33,6 +35,17 @@ impl FileWriter {
         }
     }
 
+    /// Append the given entry to the archive. After successfully calling this function, writing to
+    /// the archive now writes to this entry.
+    pub fn append_entry(&mut self, entry: &mut WriteEntry) -> crate::Result<()> {
+        unsafe {
+            match ffi::archive_write_header(self.handle_mut(), entry.entry_mut()) {
+                ffi::ARCHIVE_OK => Ok(()),
+                _ => Err(ArchiveError::from(self as &dyn Handle).into()),
+            }
+        }
+    }
+
     pub fn append_data<R: Read>(&mut self, entry: &mut WriteEntry, r: &mut R) -> crate::Result<()> {
         unsafe {
             match ffi::archive_write_header(self.handle_mut(), entry.entry_mut()) {
@@ -109,3 +122,23 @@ impl Drop for FileWriter {
         }
     }
 }
+
+impl Write for FileWriter {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        let res = unsafe {
+            ffi::archive_write_data(self.handle_mut(), buf.as_ptr() as *const c_void, buf.len())
+        } as isize;
+
+        if res < 0 {
+            Err(ArchiveError::from(self as &dyn Handle).into())
+        } else {
+            // Unwrap is safe as we check if the value is negative in the if statement
+            Ok(res.try_into().unwrap())
+        }
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        // Libarchive doesn't seem to provide a flush mechanism
+        Ok(())
+    }
+}

libarchive/src/write/mod.rs

@@ -3,6 +3,7 @@ mod file;
 
 use crate::Entry;
 pub use builder::Builder;
+pub use file::FileWriter;
 use libarchive3_sys::ffi;
 
 pub struct WriteEntry {