diff options
author | David Oberhollenzer <david.oberhollenzer@sigma-star.at> | 2023-06-04 14:36:25 +0200 |
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committer | David Oberhollenzer <david.oberhollenzer@sigma-star.at> | 2023-06-04 15:09:05 +0200 |
commit | 723306c417b3b0f8e6a3904906d6c5612cace432 (patch) | |
tree | 34235c4e6e11a1702e61d81f4f58bc9f3da57c58 /lib/io/src/win32 | |
parent | 061fbc12fe49ff49088a644def3227d3800cd8a7 (diff) |
libio: Move istream_t precache logic into backend implementation
The end goal is to remove direct buffer access from the istream_t
interfaces and make that opaque. For the tar implementation, this
already safes us needless buffer copying, as we essentially allow
the user to read-through from the underlying stream.
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Diffstat (limited to 'lib/io/src/win32')
-rw-r--r-- | lib/io/src/win32/istream.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/lib/io/src/win32/istream.c b/lib/io/src/win32/istream.c index be3d829..918b868 100644 --- a/lib/io/src/win32/istream.c +++ b/lib/io/src/win32/istream.c @@ -23,6 +23,21 @@ static int file_precache(istream_t *strm) DWORD diff, actual; HANDLE hnd; + if (strm->buffer_offset >= strm->buffer_used) { + strm->buffer_offset = 0; + strm->buffer_used = 0; + } else if (strm->buffer_offset > 0) { + memmove(strm->buffer, + strm->buffer + strm->buffer_offset, + strm->buffer_used - strm->buffer_offset); + + strm->buffer_used -= strm->buffer_offset; + strm->buffer_offset = 0; + } + + if (strm->eof) + return 0; + hnd = file->path == NULL ? GetStdHandle(STD_INPUT_HANDLE) : file->hnd; while (strm->buffer_used < sizeof(file->buffer)) { |