color: Add an intermediate buffer

cfprintf() on an unbuffered file like stderr was causing a lot of
write() calls since every format specifier resulted in a separate
fwrite().  This led to inefficiency and bad interleaving.  Add our own
dstring buffer to smooth it out.

1 files changed, 2 insertions, 0 deletions

diff --git a/color.h b/color.h
index fabac13..55e89ff 100644
--- a/color.h
+++ b/color.h
@@ -56,6 +56,8 @@ typedef struct CFILE {
 	FILE *file;
 	/** The color table to use, if any. */
 	const struct colors *colors;
+	/** A buffer for colored formatting. */
+	char *buffer;
 	/** Whether to close the underlying stream. */
 	bool close;
 } CFILE;