istream-seekable.c revision a6f281d078ed03d555802c1a8e15fefce80132dc
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainen/* Copyright (c) 2005-2012 Dovecot authors, see the included COPYING file */
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen int (*fd_callback)(const char **path_r, void *context);
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen unsigned int cur_idx;
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainenstatic void i_stream_seekable_close(struct iostream_private *stream)
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen struct seekable_istream *sstream = (struct seekable_istream *)stream;
4823da41d112ff9f5e8f088b0e60d1636e01ff92Timo Sirainen unsigned int i;
72e9e7ad158101d46860b42c4080e894485c78c3Timo Sirainenstatic void unref_streams(struct seekable_istream *sstream)
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen unsigned int i;
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainenstatic void i_stream_seekable_destroy(struct iostream_private *stream)
9945ad9e528188521d876b80f08a648072ffa207Timo Sirainen struct seekable_istream *sstream = (struct seekable_istream *)stream;
992a13add4eea0810e4db0f042a595dddf85536aTimo Siraineni_stream_seekable_set_max_buffer_size(struct iostream_private *stream,
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen struct seekable_istream *sstream = (struct seekable_istream *)stream;
4edf90751f075cc6ab3d6f53fc78b656efa80922Timo Sirainen unsigned int i;
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen i_stream_set_max_buffer_size(sstream->fd_input, max_size);
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen i_stream_set_max_buffer_size(sstream->input[i], max_size);
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainenstatic int copy_to_temp_file(struct seekable_istream *sstream)
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen struct istream_private *stream = &sstream->istream;
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainen const unsigned char *buffer;
992a13add4eea0810e4db0f042a595dddf85536aTimo Sirainen fd = sstream->fd_callback(&path, sstream->context);
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen /* copy our currently read buffer to it */
dd4b5f14b71b01a84af942e720a2d6e5f15ee1a7Timo Sirainen if (write_full(fd, sstream->membuf->data, sstream->membuf->used) < 0) {
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen i_stream_create_fd(fd, sstream->istream.max_buffer_size, TRUE);
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen /* read back the data we just had in our buffer */
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen i_stream_seek(sstream->fd_input, stream->istream.v_offset);
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen buffer = i_stream_get_data(sstream->fd_input, &size);
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen i_error("istream-seekable: Couldn't read back "
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainen "in-memory input %s",
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainenstatic ssize_t read_more(struct seekable_istream *sstream)
fd2f5fbc1f07aa93e2214a28cdf02437fb7d06c8Timo Sirainen while ((ret = i_stream_read(sstream->cur_input)) < 0) {
fd2f5fbc1f07aa93e2214a28cdf02437fb7d06c8Timo Sirainen /* full / error */
7c95b03620a03a43dd72d39608cea5fc77393ad6Timo Sirainen /* go to next stream */
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainen sstream->cur_input = sstream->input[sstream->cur_idx++];
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainen /* last one, EOF */
a40d26f83af808a0ea1e212c001d682a96d870b0Timo Sirainen sstream->size = sstream->istream.istream.v_offset;
4bbee99b3aef449a9a2a11a5b5cf1ca486915c49Timo Sirainen /* see if stream has pending data */
fd2f5fbc1f07aa93e2214a28cdf02437fb7d06c8Timo Sirainen size = i_stream_get_data_size(sstream->cur_input);
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainenstatic bool read_from_buffer(struct seekable_istream *sstream, ssize_t *ret_r)
992a13add4eea0810e4db0f042a595dddf85536aTimo Sirainen struct istream_private *stream = &sstream->istream;
992a13add4eea0810e4db0f042a595dddf85536aTimo Sirainen const unsigned char *data;
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainen if (stream->istream.v_offset + stream->pos >= sstream->membuf->used) {
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainen /* need to read more */
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainen if (sstream->membuf->used >= stream->max_buffer_size)
e015e2f7e7f48874495f9df8b0dd192b7ffcb5ccTimo Sirainen /* read more to buffer */
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen /* we should have more now. */
6a19e109ee8c5a6f688da83a86a7f6abeb71abddTimo Sirainen data = i_stream_get_data(sstream->cur_input, &size);
4edf90751f075cc6ab3d6f53fc78b656efa80922Timo Sirainen stream->buffer = CONST_PTR_OFFSET(sstream->membuf->data, offset);
4edf90751f075cc6ab3d6f53fc78b656efa80922Timo Sirainenstatic int i_stream_seekable_write_failed(struct seekable_istream *sstream)
4b058f90f9e8a2c6b2eed275de4eb8cc5195a71dTimo Sirainen struct istream_private *stream = &sstream->istream;
4edf90751f075cc6ab3d6f53fc78b656efa80922Timo Sirainen buffer_create_dynamic(default_pool, sstream->write_peak);
a40d26f83af808a0ea1e212c001d682a96d870b0Timo Sirainen data = buffer_append_space_unsafe(sstream->membuf, sstream->write_peak);
7416b94f38e82381abd9cee660efdcf3e7b773afTimo Sirainen if (pread_full(sstream->fd, data, sstream->write_peak, 0) < 0) {
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen i_error("read(%s) failed: %m", sstream->temp_path);
fd2f5fbc1f07aa93e2214a28cdf02437fb7d06c8Timo Sirainenstatic ssize_t i_stream_seekable_read(struct istream_private *stream)
aff7542e1d2f48b030560a4f01096a2cc3f671ceTimo Sirainen struct seekable_istream *sstream = (struct seekable_istream *)stream;
fd2f5fbc1f07aa93e2214a28cdf02437fb7d06c8Timo Sirainen const unsigned char *data;
d5cebe7f98e63d4e2822863ef2faa4971e8b3a5dTimo Sirainen /* copy everything to temp file and use it as the stream */
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen i_assert(stream->istream.v_offset + stream->pos <= sstream->write_peak);
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen if (stream->istream.v_offset + stream->pos == sstream->write_peak) {
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen /* need to read more */
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen /* save to our file */
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen data = i_stream_get_data(sstream->cur_input, &size);
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen if (i_stream_seekable_write_failed(sstream) < 0)
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen i_stream_seek(sstream->fd_input, stream->istream.v_offset);
d22390f33eedbd2413debabc0662dde5241b1aa6Timo Sirainen stream->buffer = i_stream_get_data(sstream->fd_input, &pos);
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen ret = pos > stream->pos ? (ssize_t)(pos - stream->pos) : ret;
13c6532dc104d23061e6901783ceb1ff8872c206Timo Sirainenstatic const struct stat *
d22390f33eedbd2413debabc0662dde5241b1aa6Timo Siraineni_stream_seekable_stat(struct istream_private *stream, bool exact)
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen struct seekable_istream *sstream = (struct seekable_istream *)stream;
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen /* we've already reached EOF and know the size */
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen /* we want to know the full size of the file, so read until
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen we're finished */
58be9d6bcc3800f5b3d76a064ee767fbe31a5a8aTimo Sirainen } while ((ret = i_stream_seekable_read(stream)) > 0);
d22390f33eedbd2413debabc0662dde5241b1aa6Timo Sirainen i_panic("i_stream_stat() used for non-blocking "
d22390f33eedbd2413debabc0662dde5241b1aa6Timo Sirainen i_stream_skip(&stream->istream, stream->pos - stream->skip);
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen /* using a file backed buffer, we can use real fstat() */
13c6532dc104d23061e6901783ceb1ff8872c206Timo Sirainen return i_stream_stat(sstream->fd_input, exact);
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen /* buffer is completely in memory */
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen stream->statbuf.st_size = sstream->membuf->used;
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Siraineni_stream_create_seekable(struct istream *input[],
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen int (*fd_callback)(const char **path_r, void *context),
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen const unsigned char *data;
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen unsigned int count;
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen /* If all input streams are seekable, use concat istream instead */
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen for (count = 0; input[count] != NULL; count++) {
365435901c22df7e5838f574c950b0e32e77f78aTimo Sirainen /* if any of the streams isn't blocking, set ourself also nonblocking */
365435901c22df7e5838f574c950b0e32e77f78aTimo Sirainen for (count = 0; input[count] != NULL; count++) {
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen sstream->membuf = buffer_create_dynamic(default_pool, BUF_INITIAL_SIZE);
6fdf8b5e4e71a69f5974f59eec2b8c19bc421fe2Timo Sirainen sstream->istream.max_buffer_size = max_buffer_size;
a817fdcc43aedf423e2134091d5f83f91d64bcc9Timo Sirainen sstream->input = i_new(struct istream *, count + 1);
a817fdcc43aedf423e2134091d5f83f91d64bcc9Timo Sirainen memcpy(sstream->input, input, sizeof(*input) * count);
0cb2e8eb55e70f8ebe1e8349bdf49e4cbe5d8834Timo Sirainen /* initialize our buffer from first stream's pending data */
8aacc9e7c84f8376822823ec98c2f551d4919b2eTimo Sirainen data = i_stream_get_data(sstream->cur_input, &size);