openpgp: Make {is,possible}_{message,keyring,tpk} return a Result

  - PacketParserEOF::is_message, PacketParserEOF::is_keyring,
    PacketParserEOF::is_tpk, PacketParserResult::possible_message,
    PacketParserResult::possible_keyring, and
    PacketParserResult::possible_tpk returned a boolean.

  - Change them to return a Result<()> instead, which is more Rusty,
    and, in particular, allows the caller to determine why the message
    didn't parse.

2 files changed, 11 insertions, 11 deletions

diff --git a/tool/src/commands/inspect.rs b/tool/src/commands/inspect.rs
index 0ba21dd9..84e66520 100644
--- a/tool/src/commands/inspect.rs
+++ b/tool/src/commands/inspect.rs
@@ -31,7 +31,9 @@ pub fn inspect(m: &clap::ArgMatches, output: &mut io::Write)
     while let PacketParserResult::Some(mut pp) = ppr {
         match pp.packet {
             Packet::PublicKey(_) | Packet::SecretKey(_) => {
-                if ! pp.possible_tpk() && pp.possible_keyring() {
+                if pp.possible_tpk().is_err()
+                    && pp.possible_keyring().is_ok()
+                {
                     if ! type_called {
                         writeln!(output, "OpenPGP Keyring.")?;
                         writeln!(output)?;
@@ -53,7 +55,7 @@ pub fn inspect(m: &clap::ArgMatches, output: &mut io::Write)
             _ => (),
         }
 
-        let possible_keyring = pp.possible_keyring();
+        let possible_keyring = pp.possible_keyring().is_ok();
         let (packet, ppr_) = pp.recurse()?;
         ppr = ppr_;
 
@@ -70,7 +72,7 @@ pub fn inspect(m: &clap::ArgMatches, output: &mut io::Write)
     }
 
     if let PacketParserResult::EOF(eof) = ppr {
-        if eof.is_message() {
+        if eof.is_message().is_ok() {
             writeln!(output, "{}OpenPGP Message.",
                      match (encrypted, ! sigs.is_empty()) {
                          (false, false) => "",
@@ -92,7 +94,7 @@ pub fn inspect(m: &clap::ArgMatches, output: &mut io::Write)
                          if literal_prefix.len() == 40 { "..." } else { "" })?;
             }
 
-        } else if eof.is_tpk() || eof.is_keyring() {
+        } else if eof.is_tpk().is_ok() || eof.is_keyring().is_ok() {
             let pp = openpgp::PacketPile::from(packets);
             let tpk = openpgp::TPK::from_packet_pile(pp)?;
             inspect_tpk(output, &tpk, print_keygrips, print_certifications)?;
diff --git a/tool/src/commands/sign.rs b/tool/src/commands/sign.rs
index bcead074..f527f3a7 100644
--- a/tool/src/commands/sign.rs
+++ b/tool/src/commands/sign.rs
@@ -8,7 +8,7 @@ extern crate sequoia_openpgp as openpgp;
 use openpgp::armor;
 use openpgp::constants::DataFormat;
 use openpgp::crypto;
-use openpgp::{Packet, Error, Result};
+use openpgp::{Packet, Result};
 use openpgp::packet::Signature;
 use openpgp::parse::{
     Parse,
@@ -179,9 +179,8 @@ fn sign_message(input: &mut io::Read, output_path: Option<&str>,
         };
 
     while let PacketParserResult::Some(mut pp) = ppr {
-        if ! pp.possible_message() {
-            return Err(Error::MalformedMessage(
-                "Malformed OpenPGP message".into()).into());
+        if let Err(err) = pp.possible_message() {
+            return Err(err.context("Malformed OpenPGP message").into());
         }
 
         match pp.packet {
@@ -301,9 +300,8 @@ fn sign_message(input: &mut io::Read, output_path: Option<&str>,
     }
 
     if let PacketParserResult::EOF(eof) = ppr {
-        if ! eof.is_message() {
-            return Err(Error::MalformedMessage(
-                "Malformed OpenPGP message".into()).into());
+        if let Err(err) = eof.is_message() {
+            return Err(err.context("Malformed OpenPGP message").into());
         }
     } else {
         unreachable!()