src/lib/istream.c

	istream.c revision 89e195dfb5c4b0efd9b9f459771a4467674e5b1f
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen/*
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen   istream.c : Input stream handling
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    Copyright (c) 2002 Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    Permission is hereby granted, free of charge, to any person obtaining
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    a copy of this software and associated documentation files (the
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    "Software"), to deal in the Software without restriction, including
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    without limitation the rights to use, copy, modify, merge, publish,
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    distribute, sublicense, and/or sell copies of the Software, and to
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    permit persons to whom the Software is furnished to do so, subject to
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    the following conditions:
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    The above copyright notice and this permission notice shall be
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    included in all copies or substantial portions of the Software.
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen*/
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen#include "lib.h"
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen#include "istream-internal.h"
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_ref(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
daf029d2a627daa39d05507140f385162828172eTimo Sirainen    _io_stream_ref(&stream->real_stream->iostream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_unref(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
daf029d2a627daa39d05507140f385162828172eTimo Sirainen    _io_stream_unref(&stream->real_stream->iostream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenint i_stream_get_fd(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    return _stream->fd;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_close(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
daf029d2a627daa39d05507140f385162828172eTimo Sirainen    _io_stream_close(&stream->real_stream->iostream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    stream->closed = TRUE;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_set_max_buffer_size(struct istream *stream, size_t max_size)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
daf029d2a627daa39d05507140f385162828172eTimo Sirainen    _io_stream_set_max_buffer_size(&stream->real_stream->iostream,
daf029d2a627daa39d05507140f385162828172eTimo Sirainen                       max_size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_set_blocking(struct istream *stream, int timeout_msecs,
f923659c0e5298263d80622c99f4dc4132b4675bTimo Sirainen               void (*timeout_cb)(void *), void *context)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
daf029d2a627daa39d05507140f385162828172eTimo Sirainen    _io_stream_set_blocking(&stream->real_stream->iostream, timeout_msecs,
f923659c0e5298263d80622c99f4dc4132b4675bTimo Sirainen                timeout_cb, context);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_set_start_offset(struct istream *stream, uoff_t offset)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    off_t diff;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    i_assert(stream->v_size == 0 ||
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen         offset <= stream->start_offset + stream->v_size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (offset == stream->start_offset)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    diff = (off_t)stream->start_offset - (off_t)offset;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    stream->start_offset = offset;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    stream->v_offset += diff;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (stream->v_size != 0) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->v_size += diff;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->v_limit += diff;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    /* reset buffer data */
3e25b17126e9536736d5da03697613e4c3af5f76Timo Sirainen    _stream->skip = _stream->pos = 0;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_set_read_limit(struct istream *stream, uoff_t v_offset)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    uoff_t max_pos;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    i_assert(stream->v_size == 0 || v_offset <= stream->v_size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (v_offset == 0)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->v_limit = stream->v_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    else {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        i_assert(v_offset >= stream->v_offset);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->v_limit = v_offset;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        max_pos = v_offset - stream->v_offset + _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        if (_stream->pos > max_pos)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            _stream->pos = max_pos;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenssize_t i_stream_read(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (stream->closed)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return -1;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    return _stream->read(_stream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_skip(struct istream *stream, uoff_t count)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    size_t data_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    i_assert(stream->v_size == 0 ||
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen         stream->v_offset + count <= stream->v_size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (count <= _stream->pos - _stream->skip) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        stream->v_offset += count;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        _stream->skip += count;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (stream->closed)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    data_size = _stream->pos - _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->skip = _stream->pos;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    count -= data_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    stream->v_offset += data_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->skip_count(_stream, count);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenvoid i_stream_seek(struct istream *stream, uoff_t v_offset)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    i_assert(v_offset <= stream->v_size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (stream->closed)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->seek(_stream, v_offset);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenchar *i_stream_next_line(struct istream *stream)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    char *ret_buf;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        size_t i;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        i_assert(stream != NULL);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (_stream->skip >= _stream->pos)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return NULL;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (_stream->w_buffer == NULL) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        i_error("i_stream_next_line() called for unmodifyable stream");
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return NULL;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
5254d77805cd35b9356d072ba325c356c43b0d51Timo Sirainen    /* @UNSAFE */
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    ret_buf = NULL;
3e25b17126e9536736d5da03697613e4c3af5f76Timo Sirainen    for (i = _stream->skip; i < _stream->pos; i++) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        if (_stream->buffer[i] == 10) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            /* got it */
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            if (i > 0 && _stream->buffer[i-1] == '\r')
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen                _stream->w_buffer[i-1] = '\0';
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            else
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen                _stream->w_buffer[i] = '\0';
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            ret_buf = (char *) _stream->w_buffer + _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            i++;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            stream->v_offset += i - _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            _stream->skip = i;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen                        break;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return ret_buf;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainenchar *i_stream_read_next_line(struct istream *stream)
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen{
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen    char *line;
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen    line = i_stream_next_line(stream);
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen    if (line != NULL)
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen        return line;
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen    if (i_stream_read(stream) > 0)
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen        line = i_stream_next_line(stream);
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen    return line;
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen}
89e195dfb5c4b0efd9b9f459771a4467674e5b1fTimo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenconst unsigned char *i_stream_get_data(struct istream *stream, size_t *size)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (_stream->skip >= _stream->pos) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        *size = 0;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return NULL;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        *size = _stream->pos - _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return _stream->buffer + _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenunsigned char *i_stream_get_modifyable_data(struct istream *stream,
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen                        size_t *size)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    if (_stream->skip >= _stream->pos || _stream->w_buffer == NULL) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        *size = 0;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return NULL;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        *size = _stream->pos - _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        return _stream->w_buffer + _stream->skip;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenint i_stream_read_data(struct istream *stream, const unsigned char **data,
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen               size_t *size, size_t threshold)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen    struct _istream *_stream = stream->real_stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    ssize_t ret = 0;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    while (_stream->pos - _stream->skip <= threshold) {
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        /* we need more data */
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        ret = _stream->read(_stream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        if (ret < 0)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen            break;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    }
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    *data = i_stream_get_data(stream, size);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    return *size > threshold ? 1 :
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        ret == -2 ? -2 :
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen        *size > 0 ? 0 : -1;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainenstruct istream *_i_stream_create(struct _istream *_stream, pool_t pool, int fd,
c0435c854a0e7246373b9752d163095cc4fbe985Timo Sirainen                 uoff_t start_offset, uoff_t v_size)
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen{
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->fd = fd;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->istream.start_offset = start_offset;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->istream.v_size = v_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->istream.v_limit = v_size;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _stream->istream.real_stream = _stream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    _io_stream_init(pool, &_stream->iostream);
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen    return &_stream->istream;
ecc81625167ed96c04c02aa190a1ea5baa65b474Timo Sirainen}