feat(content): add baseline read functionality

src/content/mod.rs

@@ -1 +1,2 @@
 pub mod path;
+pub mod read;

src/content/read.rs

@@ -0,0 +1,12 @@
+use crate::content::path::content_path;
+use ssri::Integrity;
+use std::path::Path;
+use std::fs::File;
+
+pub fn open(cache: &Path, sri: &Integrity) -> std::io::Result<File> {
+    File::open(content_path(&cache, &sri))
+}
+
+pub fn copy(cache: &Path, sri: &Integrity, to: &Path) -> std::io::Result<u64> {
+    std::fs::copy(content_path(&cache, &sri), to)
+}

src/lib.rs

@@ -1,2 +1,3 @@
 mod content;
 pub use crate::content::path;
+pub use crate::content::read;