openpgp: Make tracing less invasive.

  - Add a few macros to simplify tracing.

  - Use them.

1 files changed, 52 insertions, 0 deletions

diff --git a/openpgp/src/macros.rs b/openpgp/src/macros.rs
new file mode 100644
index 00000000..6317a0fe
--- /dev/null
+++ b/openpgp/src/macros.rs
@@ -0,0 +1,52 @@
+use std::cmp;
+
+macro_rules! trace {
+    ( $TRACE:expr, $fmt:expr, $($pargs:expr),* ) => {
+        if $TRACE {
+            eprintln!($fmt, $($pargs),*);
+        }
+    };
+    ( $TRACE:expr, $fmt:expr ) => {
+        trace!($TRACE, $fmt, );
+    };
+}
+
+// Converts an indentation level to whitespace.
+pub(crate) fn indent(i: usize) -> &'static str {
+    let s = "                                                  ";
+    &s[0..cmp::min(i, s.len())]
+}
+
+macro_rules! tracer {
+    ( $TRACE:expr, $func:expr, $indent:expr ) => {
+        // Currently, Rust doesn't support $( ... ) in a nested
+        // macro's definition.  See:
+        // https://users.rust-lang.org/t/nested-macros-issue/8348/2
+        macro_rules! t {
+            ( $fmt:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, $fmt) };
+            ( $fmt:expr, $a:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a)) };
+            ( $fmt:expr, $a:expr, $b:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f, $g)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr, $h:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f, $g, $h)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr, $h:expr, $i:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f, $g, $h, $i)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr, $h:expr, $i:expr, $j:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f, $g, $h, $i, $j)) };
+            ( $fmt:expr, $a:expr, $b:expr, $c:expr, $d:expr, $e:expr, $f:expr, $g:expr, $h:expr, $i:expr, $j:expr, $k:expr ) =>
+            { trace!($TRACE, "{}{}: {}", ::macros::indent($indent as usize), $func, format!($fmt, $a, $b, $c, $d, $e, $f, $g, $h, $i, $j, $k)) };
+        }
+    }
+}