From 1370963723917eed6c93e28c9970a2b27be57ea4 Mon Sep 17 00:00:00 2001 From: David Oberhollenzer Date: Sun, 4 Jun 2023 20:26:14 +0200 Subject: libio: remove buffer_offset from istream_t Instead, make the buffer const, let the user adjust the pointer and size. The offset can then be inferred in precache. Signed-off-by: David Oberhollenzer --- lib/io/src/unix/istream.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-) (limited to 'lib/io/src/unix') diff --git a/lib/io/src/unix/istream.c b/lib/io/src/unix/istream.c index 24b18d6..db870d9 100644 --- a/lib/io/src/unix/istream.c +++ b/lib/io/src/unix/istream.c @@ -17,25 +17,21 @@ typedef struct { static int file_precache(istream_t *strm) { file_istream_t *file = (file_istream_t *)strm; - ssize_t ret; - size_t diff; - - 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; - } - while (!strm->eof && strm->buffer_used < sizeof(file->buffer)) { - diff = sizeof(file->buffer) - strm->buffer_used; + assert(strm->buffer >= file->buffer); + assert(strm->buffer <= (file->buffer + BUFSZ)); + assert(strm->buffer_used <= BUFSZ); + assert((size_t)(strm->buffer - file->buffer) <= + (BUFSZ - strm->buffer_used)); + + if (strm->buffer_used > 0) + memmove(file->buffer, strm->buffer, strm->buffer_used); + + strm->buffer = file->buffer; - ret = read(file->fd, strm->buffer + strm->buffer_used, diff); + while (!strm->eof && strm->buffer_used < BUFSZ) { + ssize_t ret = read(file->fd, file->buffer + strm->buffer_used, + BUFSZ - strm->buffer_used); if (ret == 0) strm->eof = true; -- cgit v1.2.3