istream-chain.c revision d295cff1b640240cd198b9c8e963c9116ab95510
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher/* Copyright (c) 2003-2014 Dovecot authors, see the included COPYING file */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan#include "lib.h"
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan#include "llist.h"
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher#include "istream-private.h"
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher#include "istream-chain.h"
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstruct chain_istream;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagherstruct istream_chain_link {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream_chain_link *prev, *next;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher struct istream *stream;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher bool eof;
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher};
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstruct istream_chain {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream_chain_link *head, *tail;
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher struct chain_istream *stream;
b355dcb54194f498921743ca33304eac35d89718Stephen Gallagher};
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagherstruct chain_istream {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher struct istream_private istream;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher size_t prev_stream_left, prev_skip;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher struct istream_chain chain;
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher};
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstatic void ATTR_NULL(2)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivani_stream_chain_append_internal(struct istream_chain *chain,
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream *stream)
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher{
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream_chain_link *link;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (stream == NULL && chain->tail != NULL && chain->tail->stream == NULL)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher link = i_new(struct istream_chain_link, 1);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher link->stream = stream;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher link->eof = stream == NULL;
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher if (stream != NULL)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_ref(stream);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (chain->head == NULL && stream != NULL) {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (chain->stream->istream.max_buffer_size == 0) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan chain->stream->istream.max_buffer_size =
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->real_stream->max_buffer_size;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan } else {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_set_max_buffer_size(stream,
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher chain->stream->istream.max_buffer_size);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher DLLIST2_APPEND(&chain->head, &chain->tail, link);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher /* if io_add_istream() has been added to this chain stream, notify
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher the callback that we have more data available. */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_set_input_pending(stream, TRUE);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher}
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallaghervoid i_stream_chain_append(struct istream_chain *chain, struct istream *stream)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan{
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_chain_append_internal(chain, stream);
52261fe16203dec6e6f69177c6d0a810b47d073fStephen Gallagher}
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallaghervoid i_stream_chain_append_eof(struct istream_chain *chain)
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher{
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_chain_append_internal(chain, NULL);
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher}
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstatic void
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivani_stream_chain_set_max_buffer_size(struct iostream_private *stream,
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan size_t max_size)
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher{
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct chain_istream *cstream = (struct chain_istream *)stream;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream_chain_link *link = cstream->chain.head;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.max_buffer_size = max_size;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan while (link != NULL) {
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan if (link->stream != NULL)
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan i_stream_set_max_buffer_size(link->stream, max_size);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan link = link->next;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher }
52261fe16203dec6e6f69177c6d0a810b47d073fStephen Gallagher}
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagherstatic void i_stream_chain_destroy(struct iostream_private *stream)
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher{
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher struct chain_istream *cstream = (struct chain_istream *)stream;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct istream_chain_link *link = cstream->chain.head;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan while (link != NULL) {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher struct istream_chain_link *next = link->next;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (link->stream != NULL)
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_unref(&link->stream);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_free(link);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan link = next;
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher }
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher i_free(cstream->istream.w_buffer);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan}
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstatic void i_stream_chain_read_next(struct chain_istream *cstream)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan{
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher struct istream_chain_link *link = cstream->chain.head;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher struct istream *prev_input;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher const unsigned char *data;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan size_t data_size, size, cur_data_pos;
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher i_assert(link != NULL && link->stream != NULL);
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan i_assert(link->stream->eof);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher prev_input = link->stream;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan data = i_stream_get_data(prev_input, &data_size);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher DLLIST2_REMOVE(&cstream->chain.head, &cstream->chain.tail, link);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_free(link);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher /* a) we have more streams, b) we have EOF, c) we need to wait
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher for more streams */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan link = cstream->chain.head;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (link != NULL && link->stream != NULL)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_seek(link->stream, 0);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (cstream->prev_stream_left > 0) {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher /* we've already buffered some of the prev_input. continue
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan appending the rest to it. */
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher cur_data_pos = cstream->istream.pos -
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher (cstream->istream.skip + cstream->prev_stream_left);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(cur_data_pos <= data_size);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher data += cur_data_pos;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher data_size -= cur_data_pos;
52261fe16203dec6e6f69177c6d0a810b47d073fStephen Gallagher } else {
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher cstream->istream.pos = 0;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher cstream->istream.skip = 0;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher cstream->prev_stream_left = 0;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher }
2ea6196484055397cc4bc011c5960f790431fa9dStephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* we already verified that the data size is less than the
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan maximum buffer size */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (data_size > 0) {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (!i_stream_try_alloc(&cstream->istream, data_size, &size))
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher i_unreached();
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(size >= data_size);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher }
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher memcpy(cstream->istream.w_buffer + cstream->istream.pos,
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher data, data_size);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->istream.pos += data_size;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->prev_stream_left += data_size;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_skip(prev_input, i_stream_get_data_size(prev_input));
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_unref(&prev_input);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher}
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivanstatic ssize_t i_stream_chain_read(struct istream_private *stream)
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan{
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan struct chain_istream *cstream = (struct chain_istream *)stream;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan struct istream_chain_link *link = cstream->chain.head;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan const unsigned char *data;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan size_t size, data_size, cur_data_pos, new_pos, bytes_skipped;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan size_t new_bytes_count;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan ssize_t ret;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (link != NULL && link->eof) {
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher stream->istream.eof = TRUE;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return -1;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(stream->skip >= cstream->prev_skip);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher bytes_skipped = stream->skip - cstream->prev_skip;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (cstream->prev_stream_left == 0) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* no need to worry about buffers, skip everything */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan } else if (bytes_skipped < cstream->prev_stream_left) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* we're still skipping inside buffer */
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->prev_stream_left -= bytes_skipped;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher bytes_skipped = 0;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher } else {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* done with the buffer */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan bytes_skipped -= cstream->prev_stream_left;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->prev_stream_left = 0;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher }
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher stream->pos -= bytes_skipped;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher stream->skip -= bytes_skipped;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->buffer += bytes_skipped;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->prev_skip = stream->skip;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (link == NULL) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(bytes_skipped == 0);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return 0;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_skip(link->stream, bytes_skipped);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(stream->pos >= stream->skip + cstream->prev_stream_left);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cur_data_pos = stream->pos - (stream->skip + cstream->prev_stream_left);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan data = i_stream_get_data(link->stream, &data_size);
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher if (data_size > cur_data_pos)
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher ret = 0;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan else {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* need to read more */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(cur_data_pos == data_size);
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher ret = i_stream_read(link->stream);
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher if (ret == -2 || ret == 0)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return ret;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (ret == -1) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (link->stream->stream_errno != 0) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan io_stream_set_error(&stream->iostream,
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan "read(%s) failed: %s",
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_get_name(link->stream),
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher i_stream_get_error(link->stream));
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher stream->istream.stream_errno =
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan link->stream->stream_errno;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan return -1;
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan }
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan /* EOF of this stream, go to next stream */
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher i_stream_chain_read_next(cstream);
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher cstream->prev_skip = stream->skip;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return i_stream_chain_read(stream);
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher }
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* we read something */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan data = i_stream_get_data(link->stream, &data_size);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (cstream->prev_stream_left == 0) {
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan /* we can point directly to the current stream's buffers */
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan stream->buffer = data;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->pos -= stream->skip;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher stream->skip = 0;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan new_pos = data_size;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan } else if (data_size == cur_data_pos) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* nothing new read */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(ret == 0 || ret == -1);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->buffer = stream->w_buffer;
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher new_pos = stream->pos;
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher } else {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan /* we still have some of the previous stream left. merge the
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher new data with it. */
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_assert(data_size > cur_data_pos);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan new_bytes_count = data_size - cur_data_pos;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan if (!i_stream_try_alloc(stream, new_bytes_count, &size)) {
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->buffer = stream->w_buffer;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return -2;
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher }
c938f4ba417328fe62eded0806b2d9ca053f34a5Stephen Gallagher stream->buffer = stream->w_buffer;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher if (new_bytes_count > size)
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan new_bytes_count = size;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan memcpy(stream->w_buffer + stream->pos,
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan data + cur_data_pos, new_bytes_count);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan new_pos = stream->pos + new_bytes_count;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan }
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan ret = new_pos > stream->pos ? (ssize_t)(new_pos - stream->pos) :
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan (ret == 0 ? 0 : -1);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan stream->pos = new_pos;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->prev_skip = stream->skip;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return ret;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan}
f9fdc87c80f2744780c6a0f2bf5b1b57bcbb095aYuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivanstruct istream *i_stream_create_chain(struct istream_chain **chain_r)
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher{
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan struct chain_istream *cstream;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream = i_new(struct chain_istream, 1);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->chain.stream = cstream;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->istream.max_buffer_size = 256;
e59e09b5010f262228bbdeb92a79b733bf5854b3Stephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.iostream.destroy = i_stream_chain_destroy;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.iostream.set_max_buffer_size =
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan i_stream_chain_set_max_buffer_size;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.read = i_stream_chain_read;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.istream.readable_fd = FALSE;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan cstream->istream.istream.blocking = FALSE;
cbe7c54c2caf718bdea7ca6660ba8193d759d2d5Stephen Gallagher cstream->istream.istream.seekable = FALSE;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan *chain_r = &cstream->chain;
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan return i_stream_create(&cstream->istream, NULL, -1);
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan}
bde69429374859acff41273c0771d2b5f5c199b1Yuri Chornoivan