add dprintf(n, fmt, ...) debugging macro

dprintf(n, fmt, ...) is a more natural form of
dprint(n, (debugfile, fmt, ...)). It prints code location in the debug
file where possible.

I believe this approach, while common, was not previously used because
we were trying to be C90-compatible.  C90 doesn't provide variadic
macros.  Now we require C99, so it makes sense to add this pattern.

1 files changed, 5 insertions, 0 deletions

diff --git a/lib.h b/lib.h
index 92829252..1e98692d 100644
--- a/lib.h
+++ b/lib.h
@@ -149,12 +149,17 @@ MUTT_LIB_WHERE FILE *debugfile;
 MUTT_LIB_WHERE int debuglevel;
 
 void mutt_debug (FILE *, const char *, ...);
+void mutt_debug_f (const char *, const int, const char *, const char *, ...);
 
 #  define dprint(N,X) do { if (debuglevel>=N && debugfile) mutt_debug X; } while (0)
 
+/* __func__ is a C99 provision, but we now require C99 so it's safe */
+#  define dprintf(N, ...) do { if (debuglevel >= (N)) mutt_debug_f (__FILE__, __LINE__, __func__, __VA_ARGS__); } while (0)
+
 # else
 
 #  define dprint(N,X) do { } while (0)
+#  define dprintf(N, ...) do { } while (0)
 
 # endif