age: Add IdentityFile::from_input_reader

age/CHANGELOG.md

@@ -11,17 +11,23 @@ to 1.0.0 are beta releases.
 ## [Unreleased]
 ### Added
 - `age::cli_common::file_io`:
+  - `FileReader`
   - `impl Debug for {LazyFile, OutputFormat, OutputWriter, StdoutWriter}`
+- `age::identity::IdentityFile::from_input_reader` (behind `cli-common` feature
+  flag).
 - `impl Eq for age::ssh::{ParseRecipientKeyError, UnsupportedKey}`
 - `impl {Debug, PartialEq, Eq, Hash} for age::x25519::Recipient`
 
 ### Changed
 - MSRV is now 1.65.0.
 - Migrated to `base64 0.21`, `rsa 0.9`.
-- `age::cli_common::file_io::OutputWriter::new` now takes an `allow_overwrite`
-  boolean argument. If `OutputWriter` will write to a file, this boolean enables
-  the caller to control whether the file will be overwritten if it exists
-  (instead of the implicit behaviour that was previously changed in 0.6.0).
+- `age::cli_common::file_io`:
+  - `InputReader::File` enum variant now contains `FileReader` instead of
+    `std::fs::File`.
+  - `OutputWriter::new` now takes an `allow_overwrite` boolean argument. If
+    `OutputWriter` will write to a file, this boolean enables the caller to
+    control whether the file will be overwritten if it exists (instead of the
+    implicit behaviour that was previously changed in 0.6.0).
 - `age::ssh`:
   - `ParseRecipientKeyError` has a new variant `RsaModulusTooLarge`.
   - The following trait implementations now return

age/src/cli_common/file_io.rs

@@ -50,10 +50,16 @@ impl fmt::Display for DenyOverwriteFileError {
 
 impl std::error::Error for DenyOverwriteFileError {}
 
+/// Wrapper around a [`File`].
+pub struct FileReader {
+    inner: File,
+    filename: String,
+}
+
 /// Wrapper around either a file or standard input.
 pub enum InputReader {
     /// Wrapper around a file.
-    File(File),
+    File(FileReader),
     /// Wrapper around standard input.
     Stdin(io::Stdin),
 }
@@ -65,7 +71,10 @@ impl InputReader {
             // Respect the Unix convention that "-" as an input filename
             // parameter is an explicit request to use standard input.
             if filename != "-" {
-                return Ok(InputReader::File(File::open(filename)?));
+                return Ok(InputReader::File(FileReader {
+                    inner: File::open(&filename)?,
+                    filename,
+                }));
             }
         }
 
@@ -76,12 +85,20 @@ impl InputReader {
     pub fn is_terminal(&self) -> bool {
         matches!(self, Self::Stdin(_)) && io::stdin().is_terminal()
     }
+
+    pub(crate) fn filename(&self) -> Option<&str> {
+        if let Self::File(f) = self {
+            Some(&f.filename)
+        } else {
+            None
+        }
+    }
 }
 
 impl Read for InputReader {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         match self {
-            InputReader::File(f) => f.read(buf),
+            InputReader::File(f) => f.inner.read(buf),
             InputReader::Stdin(handle) => handle.read(buf),
         }
     }

age/src/identity.rs

@@ -3,6 +3,9 @@ use std::io;
 
 use crate::{x25519, Callbacks, DecryptError, EncryptError};
 
+#[cfg(feature = "cli-common")]
+use crate::cli_common::file_io::InputReader;
+
 #[cfg(feature = "plugin")]
 use crate::plugin;
 
@@ -70,6 +73,13 @@ impl IdentityFile {
         Self::parse_identities(None, data)
     }
 
+    /// Parses one or more identities from an [`InputReader`];
+    #[cfg(feature = "cli-common")]
+    pub fn from_input_reader(reader: InputReader) -> io::Result<Self> {
+        let filename = reader.filename().map(String::from);
+        Self::parse_identities(filename, io::BufReader::new(reader))
+    }
+
     fn parse_identities<R: io::BufRead>(filename: Option<String>, data: R) -> io::Result<Self> {
         let mut identities = vec![];