Changeset 20667af in mainline for uspace/lib/riff/include

Timestamp:

2020-11-21T19:56:45Z (5 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

68698ba

Parents:

06d0c81

git-author:

Jiri Svoboda <jiri@…> (2020-11-21 19:25:27)

git-committer:

Jiri Svoboda <jiri@…> (2020-11-21 19:56:45)

Message:

Remember current position in libriff and optimize sequential reading

TPF files currently contain a lot of chunks and each chunk means
a ftell/fseek. libc's ftell/fseek flush the I/O buffer, leading
to a lot of unnecessary IPC. This all leads to reading typeface to
take way too long.

We remember the current file position
in a RIFF reader and avoid ftell and also avoid fseek at the end
of a chunk, if possible (if we need to advance just a little bit,
we read instead of seek).

File:

• uspace/lib/riff/include/types/riff/chunk.h (modified) (1 diff)

uspace/lib/riff/include/types/riff/chunk.h

@@ -54 +54 @@
 typedef struct {
         FILE *f;
+        /** Current file position */
+        long pos;
 } riffr_t;