istream-limit.c revision 1117aa7adc2909c750031fd7551a58a486d100d8
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch/* Copyright (C) 2003 Timo Sirainen */
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch#include "lib.h"
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch#include "istream-internal.h"
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Boschstruct limit_istream {
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct _istream istream;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct istream *input;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch uoff_t v_start_offset, v_size;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch};
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Boschstatic void _close(struct _iostream *stream __attr_unused__)
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch{
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch}
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Boschstatic void _destroy(struct _iostream *stream)
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch{
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct limit_istream *lstream = (struct limit_istream *) stream;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch /* get to same position in parent stream */
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch i_stream_seek(lstream->input, lstream->v_start_offset +
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch lstream->istream.istream.v_offset);
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch i_stream_unref(lstream->input);
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch}
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Boschstatic void _set_max_buffer_size(struct _iostream *stream, size_t max_size)
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch{
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct limit_istream *lstream = (struct limit_istream *) stream;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch i_stream_set_max_buffer_size(lstream->input, max_size);
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch}
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
96fbbe9c6fd04bca25770020bf94eec50888bc9bStephan Boschstatic void _set_blocking(struct _iostream *stream, int timeout_msecs,
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch void (*timeout_cb)(void *), void *context)
659f431cb56f26ec07e308db4d6c563c0eaa5300Stephan Bosch{
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct limit_istream *lstream = (struct limit_istream *) stream;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch i_stream_set_blocking(lstream->input, timeout_msecs,
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch timeout_cb, context);
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch}
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Boschstatic ssize_t _read(struct _istream *stream)
659f431cb56f26ec07e308db4d6c563c0eaa5300Stephan Bosch{
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch struct limit_istream *lstream = (struct limit_istream *) stream;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch uoff_t left;
96fbbe9c6fd04bca25770020bf94eec50888bc9bStephan Bosch ssize_t ret;
620b60321d04006b32a116824d49b88b61be7131Stephan Bosch size_t pos;
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch
620b60321d04006b32a116824d49b88b61be7131Stephan Bosch if (stream->istream.v_offset +
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch (stream->pos - stream->skip) >= lstream->v_size)
f9511e684858bf5f6ac77ab12254b85b737beae8Stephan Bosch return -1;
if (lstream->input->v_offset !=
lstream->v_start_offset + stream->istream.v_offset) {
i_stream_seek(lstream->input,
lstream->v_start_offset +
stream->istream.v_offset);
}
if (i_stream_read(lstream->input) == -2 && stream->buffer != NULL) {
if (stream->skip == 0)
return -2;
}
stream->istream.disconnected = lstream->input->disconnected;
stream->pos -= stream->skip;
stream->skip = 0;
stream->buffer = i_stream_get_data(lstream->input, &pos);
if (lstream->v_size != (uoff_t)-1) {
left = lstream->v_size - stream->istream.v_offset;
if (pos > left)
pos = left;
}
ret = pos <= stream->pos ? -1 :
(ssize_t) (pos - stream->pos);
stream->pos = pos;
return ret;
}
static void _seek(struct _istream *stream, uoff_t v_offset)
{
stream->istream.stream_errno = 0;
stream->istream.v_offset = v_offset;
stream->skip = stream->pos = 0;
}
static uoff_t _get_size(struct _istream *stream)
{
struct limit_istream *lstream = (struct limit_istream *) stream;
return lstream->v_size != (uoff_t)-1 ? lstream->v_size :
i_stream_get_size(lstream->input);
}
struct istream *i_stream_create_limit(pool_t pool, struct istream *input,
uoff_t v_start_offset, uoff_t v_size)
{
struct limit_istream *lstream;
i_stream_ref(input);
lstream = p_new(pool, struct limit_istream, 1);
lstream->input = input;
lstream->v_start_offset = v_start_offset;
lstream->v_size = v_size;
lstream->istream.istream.v_offset =
input->v_offset < v_start_offset ? 0 :
input->v_offset - v_start_offset > v_size ? v_size :
input->v_offset - v_start_offset;
lstream->istream.iostream.close = _close;
lstream->istream.iostream.destroy = _destroy;
lstream->istream.iostream.set_max_buffer_size = _set_max_buffer_size;
lstream->istream.iostream.set_blocking = _set_blocking;
lstream->istream.read = _read;
lstream->istream.seek = _seek;
lstream->istream.get_size = _get_size;
return _i_stream_create(&lstream->istream, pool, i_stream_get_fd(input),
input->real_stream->abs_start_offset +
v_start_offset);
}