[dovecot-cvs] dovecot/src/lib iostream-internal.h,NONE,1.1 iostream.c,NONE,1.1 istream-data.c,NONE,1.1 istream-file.c,NONE,1.1 istream-internal.h,NONE,1.1 istream-mmap.c,NONE,1.1 istream.c,NONE,1.1 istream.h,NONE,1.1 ostream-file.c,NONE,1.1 Message-Id: <20021206010924.ED4BF238E1@danu.procontrol.fi>

[cras at procontrol.fi]

Update of /home/cvs/dovecot/src/lib
In directory danu:/tmp/cvs-serv6082/lib

Modified Files:
	Makefile.am lib.h 
Added Files:
	iostream-internal.h iostream.c istream-data.c istream-file.c 
	istream-internal.h istream-mmap.c istream.c istream.h 
	ostream-file.c ostream-internal.h ostream.c ostream.h 
Removed Files:
	ibuffer-data.c ibuffer-file.c ibuffer-internal.h 
	ibuffer-mmap.c ibuffer.c ibuffer.h iobuffer-internal.h 
	iobuffer.c obuffer-file.c obuffer-internal.h obuffer.c 
	obuffer.h 
Log Message:
Renamed IBuffer and OBuffer to IStream and OStream which describes their
functionality better. I tried to keep the variable names and comments also
sensible.



--- NEW FILE: iostream-internal.h ---
#ifndef __IOSTREAM_INTERNAL_H
#define __IOSTREAM_INTERNAL_H

/* This file is private to IStream and OStream implementation */

typedef struct _IOStream _IOStream;

struct _IOStream {
	Pool pool;
	int refcount;

	void (*close)(_IOStream *stream);
	void (*destroy)(_IOStream *stream);
	void (*set_max_buffer_size)(_IOStream *stream, size_t max_size);
	void (*set_blocking)(_IOStream *stream, int timeout_msecs,
			     void (*timeout_func)(void *), void *context);
};

void _io_stream_init(Pool pool, _IOStream *stream);
void _io_stream_ref(_IOStream *stream);
void _io_stream_unref(_IOStream *stream);
void _io_stream_close(_IOStream *stream);
void _io_stream_set_max_buffer_size(_IOStream *stream, size_t max_size);
void _io_stream_set_blocking(_IOStream *stream, int timeout_msecs,
			     void (*timeout_func)(void *), void *context);

#define GET_TIMEOUT_TIME(fstream) \
        ((fstream)->timeout_msecs == 0 ? 0 : \
	 time(NULL) + ((fstream)->timeout_msecs / 1000))
#define STREAM_IS_BLOCKING(fstream) \
	((fstream)->timeout_msecs != 0)

#endif

--- NEW FILE: iostream.c ---
/*
   iostream.c : Input/output stream common handling

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "iostream-internal.h"

void _io_stream_init(Pool pool, _IOStream *stream)
{
	stream->pool = pool;
	stream->refcount = 1;
}

void _io_stream_ref(_IOStream *stream)
{
	stream->refcount++;
}

void _io_stream_unref(_IOStream *stream)
{
	Pool pool;

	i_assert(stream->refcount > 0);
	if (--stream->refcount != 0)
		return;

	stream->close(stream);
	stream->destroy(stream);

	pool = stream->pool;
        p_free(pool, stream);
	pool_unref(pool);
}

void _io_stream_close(_IOStream *stream)
{
	stream->close(stream);
}

void _io_stream_set_max_buffer_size(_IOStream *stream, size_t max_size)
{
	stream->set_max_buffer_size(stream, max_size);
}

void _io_stream_set_blocking(_IOStream *stream, int timeout_msecs,
			     void (*timeout_func)(void *), void *context)
{
	stream->set_blocking(stream, timeout_msecs, timeout_func, context);
}

--- NEW FILE: istream-data.c ---
/*
   istream-data.c : Input stream interface for reading from data buffer

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "istream-internal.h"

static void _close(_IOStream *stream __attr_unused__)
{
}

static void _destroy(_IOStream *stream __attr_unused__)
{
}

static void _set_max_buffer_size(_IOStream *stream __attr_unused__,
				 size_t max_size __attr_unused__)
{
}

static void _set_blocking(_IOStream *stream __attr_unused__,
			  int timeout_msecs __attr_unused__,
			  void (*timeout_func)(void *) __attr_unused__,
			  void *context __attr_unused__)
{
}

static ssize_t _read(_IStream *stream)
{
	return stream->pos - stream->skip;
}

static void _seek(_IStream *stream, uoff_t v_offset)
{
	stream->skip = v_offset;
	stream->istream.v_offset = v_offset;
}

static void _skip(_IStream *stream, uoff_t count)
{
	stream->skip += count;
	stream->istream.v_offset += count;
}

IStream *i_stream_create_from_data(Pool pool, const unsigned char *data,
				   size_t size)
{
	_IStream *stream;

	stream = p_new(pool, _IStream, 1);
	stream->buffer = data;
	stream->pos = size;

	stream->iostream.close = _close;
	stream->iostream.destroy = _destroy;
	stream->iostream.set_max_buffer_size = _set_max_buffer_size;
	stream->iostream.set_blocking = _set_blocking;

	stream->read = _read;
	stream->skip_count = _skip;
	stream->seek = _seek;

	return _i_stream_create(stream, pool, -1, 0, size);
}

--- NEW FILE: istream-file.c ---
/*
   istream-file.c : Input stream handling for files

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "alarm-hup.h"
#include "istream-internal.h"
#include "network.h"

#include <time.h>
#include <unistd.h>
#include <sys/stat.h>

#define I_STREAM_MIN_SIZE 4096

#define STREAM_IS_BLOCKING(fstream) \
	((fstream)->timeout_msecs != 0)

typedef struct {
	_IStream istream;

	size_t max_buffer_size;
	uoff_t skip_left;

	int timeout_msecs;
	void (*timeout_func)(void *);
	void *timeout_context;

	unsigned int file:1;
	unsigned int autoclose_fd:1;
} FileIStream;

static void _close(_IOStream *stream)
{
	FileIStream *fstream = (FileIStream *) stream;
	_IStream *_stream = (_IStream *) stream;

	if (fstream->autoclose_fd && _stream->fd != -1) {
		if (close(_stream->fd) < 0)
			i_error("FileIStream.close() failed: %m");
		_stream->fd = -1;
	}
}

static void _destroy(_IOStream *stream)
{
	_IStream *_stream = (_IStream *) stream;

	p_free(_stream->iostream.pool, _stream->w_buffer);
}

static void _set_max_buffer_size(_IOStream *stream, size_t max_size)
{
	FileIStream *fstream = (FileIStream *) stream;

	fstream->max_buffer_size = max_size;
}

static void _set_blocking(_IOStream *stream, int timeout_msecs,
			  void (*timeout_func)(void *), void *context)
{
	FileIStream *fstream = (FileIStream *) stream;

	fstream->timeout_msecs = timeout_msecs;
	fstream->timeout_func = timeout_func;
	fstream->timeout_context = context;

	net_set_nonblock(fstream->istream.fd, timeout_msecs == 0);

	if (timeout_msecs != 0)
		alarm_hup_init();
}

static void i_stream_grow_buffer(_IStream *stream, size_t bytes)
{
	FileIStream *fstream = (FileIStream *) stream;

	stream->buffer_size = stream->pos + bytes;
	stream->buffer_size =
		stream->buffer_size <= I_STREAM_MIN_SIZE ? I_STREAM_MIN_SIZE :
		nearest_power(stream->buffer_size);

	if (fstream->max_buffer_size > 0 &&
	    stream->buffer_size > fstream->max_buffer_size)
		stream->buffer_size = fstream->max_buffer_size;

	stream->buffer = stream->w_buffer =
		p_realloc(stream->iostream.pool, stream->w_buffer,
			  stream->buffer_size);
}

static void i_stream_compress(_IStream *stream)
{
	memmove(stream->w_buffer, stream->w_buffer + stream->skip,
		stream->pos - stream->skip);
	stream->pos -= stream->skip;

	if (stream->skip > stream->cr_lookup_pos)
		stream->cr_lookup_pos = 0;
	else
		stream->cr_lookup_pos -= stream->skip;

	stream->skip = 0;
}

static ssize_t _read(_IStream *stream)
{
	FileIStream *fstream = (FileIStream *) stream;
	time_t timeout_time;
	uoff_t read_limit;
	size_t size;
	ssize_t ret;

	if (stream->istream.closed)
		return -1;

	if (fstream->skip_left > 0) {
		i_assert(stream->skip == stream->pos);

		if (fstream->file) {
			/* we're a file, so we can lseek() */
			i_stream_seek(&stream->istream,
				      stream->istream.v_offset);
			if (stream->istream.closed)
				return -1;
		}
	}

	stream->istream.stream_errno = 0;

	if (stream->pos == stream->buffer_size) {
		if (stream->skip > 0) {
			/* remove the unused bytes from beginning of buffer */
                        i_stream_compress(stream);
		} else if (fstream->max_buffer_size == 0 ||
			   stream->buffer_size < fstream->max_buffer_size) {
			/* buffer is full - grow it */
			i_stream_grow_buffer(stream, I_STREAM_MIN_SIZE);
		}

		if (stream->pos == stream->buffer_size)
			return -2; /* buffer full */
	}

	size = stream->buffer_size - stream->pos;
	if (stream->istream.v_limit > 0) {
		i_assert(stream->istream.v_limit >= stream->istream.v_offset);

		read_limit = stream->istream.v_limit -
			stream->istream.v_offset + fstream->skip_left;
		if (read_limit <= stream->pos - stream->skip) {
			/* virtual limit reached == EOF */
			return -1;
		}

		read_limit -= stream->pos - stream->skip;
		if (size > read_limit)
			size = read_limit;
	}

	timeout_time = GET_TIMEOUT_TIME(fstream);

	ret = -1;
	do {
		if (ret == 0 && timeout_time > 0 && time(NULL) > timeout_time) {
			/* timeouted */
			if (fstream->timeout_func != NULL)
				fstream->timeout_func(fstream->timeout_context);
			stream->istream.stream_errno = EAGAIN;
			return -1;
		}

		ret = read(stream->fd, stream->w_buffer + stream->pos, size);
		if (ret == 0) {
			/* EOF */
			stream->istream.stream_errno = 0;
			return -1;
		}

		if (ret < 0) {
			if (errno == EINTR || errno == EAGAIN)
				ret = 0;
			else {
				stream->istream.stream_errno = errno;
				return -1;
			}
		}

		if (ret > 0 && fstream->skip_left > 0) {
			if (fstream->skip_left >= (size_t)ret) {
				fstream->skip_left -= ret;
				ret = 0;
			} else {
				ret -= fstream->skip_left;
				stream->pos += fstream->skip_left;
				stream->skip += fstream->skip_left;
				fstream->skip_left = 0;
			}
		}
	} while (ret == 0 && STREAM_IS_BLOCKING(fstream));

	stream->pos += ret;
	return ret;
}

static void _skip(_IStream *stream, uoff_t count)
{
	FileIStream *fstream = (FileIStream *) stream;

	fstream->skip_left += count - (stream->pos - stream->skip);
	stream->skip = stream->pos = 0;
	stream->istream.v_offset += count;
}

static void _seek(_IStream *stream, uoff_t v_offset)
{
	FileIStream *fstream = (FileIStream *) stream;
	uoff_t real_offset;
	off_t ret;

	real_offset = stream->istream.start_offset + v_offset;
	if (real_offset > OFF_T_MAX) {
		stream->istream.stream_errno = EOVERFLOW;
		ret = -1;
	} else {
		ret = lseek(stream->fd, (off_t)real_offset, SEEK_SET);
		if (ret < 0)
			stream->istream.stream_errno = errno;
		else if (ret != (off_t)real_offset) {
			stream->istream.stream_errno = EINVAL;
			ret = -1;
		} else {
			stream->skip = stream->pos = 0;
			fstream->skip_left = 0;
		}
	}

	if (ret < 0)
                i_stream_close(&stream->istream);
	else {
		stream->istream.stream_errno = 0;
		stream->istream.v_offset = v_offset;
	}
}

IStream *i_stream_create_file(int fd, Pool pool, size_t max_buffer_size,
			      int autoclose_fd)
{
	FileIStream *fstream;
	struct stat st;

	fstream = p_new(pool, FileIStream, 1);
	fstream->max_buffer_size = max_buffer_size;
	fstream->autoclose_fd = autoclose_fd;

	fstream->istream.iostream.close = _close;
	fstream->istream.iostream.destroy = _destroy;
	fstream->istream.iostream.set_max_buffer_size = _set_max_buffer_size;
	fstream->istream.iostream.set_blocking = _set_blocking;

	fstream->istream.read = _read;
	fstream->istream.skip_count = _skip;
	fstream->istream.seek = _seek;

	/* get size of fd if it's a file */
	if (fstat(fd, &st) < 0)
		st.st_size = 0;
	else if (S_ISREG(st.st_mode))
		fstream->file = TRUE;

	return _i_stream_create(&fstream->istream, pool, fd, 0,
				(uoff_t)st.st_size);
}

--- NEW FILE: istream-internal.h ---
#ifndef __ISTREAM_INTERNAL_H
#define __ISTREAM_INTERNAL_H

#include "istream.h"
#include "iostream-internal.h"

typedef struct __IStream _IStream;

struct __IStream {
/* inheritance: */
	_IOStream iostream;

/* methods: */
	ssize_t (*read)(_IStream *stream);
	void (*skip_count)(_IStream *stream, uoff_t count);
	void (*seek)(_IStream *stream, uoff_t v_offset);

/* data: */
	IStream istream;

	int fd;
	const unsigned char *buffer;
	unsigned char *w_buffer; /* may be NULL */
	size_t buffer_size;

	size_t skip, pos, cr_lookup_pos;
};

IStream *_i_stream_create(_IStream *_buf, Pool pool, int fd,
			  uoff_t start_offset, uoff_t v_size);

#endif

--- NEW FILE: istream-mmap.c ---
/*
   istream-mmap.c : Input stream handling for mmap()ed files

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "mmap-util.h"
#include "istream-internal.h"

#include <unistd.h>
#include <sys/stat.h>

typedef struct {
	_IStream istream;

	int fd;
	void *mmap_base;
	off_t mmap_offset;
	size_t mmap_block_size;

	unsigned int autoclose_fd:1;
} MmapIStream;

static size_t mmap_pagesize = 0;
static size_t mmap_pagemask = 0;

static void _close(_IOStream *stream)
{
	MmapIStream *mstream = (MmapIStream *) stream;

	if (mstream->autoclose_fd && mstream->fd != -1) {
		if (close(mstream->fd) < 0)
			i_error("MmapIStream.close() failed: %m");
		mstream->fd = -1;
	}
}

static void i_stream_munmap(MmapIStream *mstream)
{
	_IStream *_stream = &mstream->istream;

	if (_stream->buffer != NULL) {
		if (munmap(mstream->mmap_base, _stream->buffer_size) < 0)
			i_error("MmapIStream.munmap() failed: %m");
		mstream->mmap_base = NULL;
		_stream->buffer = NULL;
		_stream->buffer_size = 0;
		mstream->mmap_offset = 0;
	}
}

static void _destroy(_IOStream *stream)
{
	MmapIStream *mstream = (MmapIStream *) stream;

	i_stream_munmap(mstream);
}

static void _set_max_buffer_size(_IOStream *stream, size_t max_size)
{
	MmapIStream *mstream = (MmapIStream *) stream;

	mstream->mmap_block_size = max_size;
}

static void _set_blocking(_IOStream *stream __attr_unused__,
			  int timeout_msecs __attr_unused__,
			  void (*timeout_func)(void *) __attr_unused__,
			  void *context __attr_unused__)
{
	/* we never block */
}

static ssize_t io_stream_set_mmaped_pos(_IStream *stream)
{
	MmapIStream *mstream = (MmapIStream *) stream;

	i_assert((uoff_t)mstream->mmap_offset <=
		 stream->istream.start_offset + stream->istream.v_limit);

	stream->pos = stream->istream.start_offset + stream->istream.v_limit -
		mstream->mmap_offset;
	if (stream->pos > stream->buffer_size)
		stream->pos = stream->buffer_size;

	return stream->pos - stream->skip;
}

static ssize_t _read(_IStream *stream)
{
	MmapIStream *mstream = (MmapIStream *) stream;
	size_t aligned_skip, limit_size;

	if (stream->istream.start_offset + stream->istream.v_limit <=
	    (uoff_t)mstream->mmap_offset + stream->pos) {
		/* end of file */
		stream->istream.stream_errno = 0;
		return -1;
	}

	if (stream->pos < stream->buffer_size) {
		/* more bytes available without needing to mmap() */
		return io_stream_set_mmaped_pos(stream);
	}

	aligned_skip = stream->skip & ~mmap_pagemask;
	if (aligned_skip == 0 && mstream->mmap_base != NULL) {
		/* didn't skip enough bytes */
		return -2;
	}

	stream->skip -= aligned_skip;
	mstream->mmap_offset += aligned_skip;

	if (mstream->mmap_base != NULL) {
		if (munmap(mstream->mmap_base, stream->buffer_size) < 0)
			i_error("io_stream_read_mmaped(): munmap() failed: %m");
	}

	stream->buffer_size = stream->istream.start_offset +
		stream->istream.v_size - mstream->mmap_offset;
	if (stream->buffer_size > mstream->mmap_block_size)
		stream->buffer_size = mstream->mmap_block_size;

	i_assert((uoff_t)mstream->mmap_offset + stream->buffer_size <=
		 stream->istream.start_offset + stream->istream.v_size);

	mstream->mmap_base = mmap(NULL, stream->buffer_size,
				  PROT_READ, MAP_PRIVATE,
				  mstream->fd, mstream->mmap_offset);
	stream->buffer = mstream->mmap_base;
	if (mstream->mmap_base == MAP_FAILED) {
		stream->istream.stream_errno = errno;
		mstream->mmap_base = NULL;
		stream->buffer = NULL;
		stream->buffer_size = 0;
		stream->skip = stream->pos = 0;
		i_error("MmapIStream.mmap() failed: %m");
		return -1;
	}

	/* madvise() only if non-limited mmap()ed buffer area larger than
	   page size */
	limit_size = stream->istream.start_offset + stream->istream.v_limit -
		mstream->mmap_offset;
	if (limit_size > mmap_pagesize) {
		if (limit_size > stream->buffer_size)
			limit_size = stream->buffer_size;

		if (madvise(mstream->mmap_base, limit_size, MADV_SEQUENTIAL) < 0)
			i_error("MmapIStream.madvise(): %m");
	}

	return io_stream_set_mmaped_pos(stream);
}

static void _seek(_IStream *stream, uoff_t v_offset)
{
	MmapIStream *mstream = (MmapIStream *) stream;
	uoff_t abs_offset;

	abs_offset = stream->istream.start_offset + v_offset;
	if (stream->buffer_size != 0 &&
	    (uoff_t)mstream->mmap_offset <= abs_offset &&
	    (uoff_t)mstream->mmap_offset + stream->buffer_size > abs_offset) {
		/* already mmaped */
		stream->skip = stream->pos = abs_offset - mstream->mmap_offset;
	} else {
		/* force reading next time */
		i_stream_munmap(mstream);
		stream->skip = stream->pos = abs_offset;
	}

	stream->istream.v_offset = v_offset;
}

static void _skip(_IStream *stream, uoff_t count)
{
	_seek(stream, stream->istream.v_offset + count);
}

IStream *i_stream_create_mmap(int fd, Pool pool, size_t block_size,
			      uoff_t start_offset, uoff_t v_size,
			      int autoclose_fd)
{
	MmapIStream *mstream;
	struct stat st;

	if (mmap_pagesize == 0) {
		mmap_pagesize = getpagesize();
		mmap_pagemask = mmap_pagesize-1;
	}

	if (v_size == 0) {
		if (fstat(fd, &st) < 0) {
			i_error("i_stream_create_mmap(): fstat() failed: %m");
			v_size = 0;
		} else {
			v_size = st.st_size;
			if (start_offset > v_size)
				start_offset = v_size;
			v_size -= start_offset;
		}
	}

	mstream = p_new(pool, MmapIStream, 1);
	mstream->fd = fd;
	mstream->mmap_block_size = block_size;
	mstream->autoclose_fd = autoclose_fd;

	mstream->istream.iostream.close = _close;
	mstream->istream.iostream.destroy = _destroy;
	mstream->istream.iostream.set_max_buffer_size = _set_max_buffer_size;
	mstream->istream.iostream.set_blocking = _set_blocking;

	mstream->istream.read = _read;
	mstream->istream.skip_count = _skip;
	mstream->istream.seek = _seek;

	return _i_stream_create(&mstream->istream, pool, fd, start_offset, v_size);
}

--- NEW FILE: istream.c ---
/*
   istream.c : Input stream handling

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "istream-internal.h"

void i_stream_ref(IStream *stream)
{
	_io_stream_ref(stream->real_stream);
}

void i_stream_unref(IStream *stream)
{
	_io_stream_unref(stream->real_stream);
}

int i_stream_get_fd(IStream *stream)
{
	_IStream *_stream = stream->real_stream;

	return _stream->fd;
}

void i_stream_close(IStream *stream)
{
	_io_stream_close(stream->real_stream);
	stream->closed = TRUE;
}

void i_stream_set_max_buffer_size(IStream *stream, size_t max_size)
{
	_io_stream_set_max_buffer_size(stream->real_stream, max_size);
}

void i_stream_set_blocking(IStream *stream, int timeout_msecs,
			   void (*timeout_func)(void *), void *context)
{
	_io_stream_set_blocking(stream->real_stream, timeout_msecs,
				timeout_func, context);
}

void i_stream_set_start_offset(IStream *stream, uoff_t offset)
{
	_IStream *_stream = stream->real_stream;
	off_t diff;

	i_assert(stream->v_size == 0 ||
		 offset <= stream->start_offset + stream->v_size);

	if (offset == stream->start_offset)
		return;

	diff = (off_t)stream->start_offset - (off_t)offset;
	stream->start_offset = offset;
	stream->v_offset += diff;
	if (stream->v_size != 0) {
		stream->v_size += diff;
		stream->v_limit += diff;
	}

	/* reset buffer data */
	_stream->skip = _stream->pos = _stream->cr_lookup_pos = 0;
}

void i_stream_set_read_limit(IStream *stream, uoff_t v_offset)
{
	_IStream *_stream = stream->real_stream;
	uoff_t max_pos;

	i_assert(stream->v_size == 0 || v_offset <= stream->v_size);

	if (v_offset == 0)
		stream->v_limit = stream->v_size;
	else {
		i_assert(v_offset >= stream->v_offset);

		stream->v_limit = v_offset;
		max_pos = v_offset - stream->v_offset + _stream->skip;
		if (_stream->pos > max_pos)
			_stream->pos = max_pos;
	}
}

ssize_t i_stream_read(IStream *stream)
{
	_IStream *_stream = stream->real_stream;

	if (stream->closed)
		return -1;

	return _stream->read(_stream);
}

void i_stream_skip(IStream *stream, uoff_t count)
{
	_IStream *_stream = stream->real_stream;
	size_t data_size;

	i_assert(stream->v_size == 0 ||
		 stream->v_offset + count <= stream->v_size);

	if (count <= _stream->pos - _stream->skip) {
		stream->v_offset += count;
		_stream->skip += count;
		return;
	}

	if (stream->closed)
		return;

	data_size = _stream->pos - _stream->skip;
	_stream->skip = _stream->pos;

	count -= data_size;
	stream->v_offset += data_size;

	_stream->skip_count(_stream, count);
}

void i_stream_seek(IStream *stream, uoff_t v_offset)
{
	_IStream *_stream = stream->real_stream;

	i_assert(v_offset <= stream->v_size);

	if (stream->closed)
		return;

	_stream->seek(_stream, v_offset);
}

char *i_stream_next_line(IStream *stream)
{
	_IStream *_stream = stream->real_stream;
	char *ret_buf;
        size_t i;

        i_assert(stream != NULL);

	if (_stream->skip >= _stream->pos)
		return NULL;

	if (_stream->w_buffer == NULL) {
		i_error("i_stream_next_line() called for unmodifyable stream");
		return NULL;
	}

	ret_buf = NULL;
	for (i = _stream->cr_lookup_pos; i < _stream->pos; i++) {
		if (_stream->buffer[i] == 10) {
			/* got it */
			if (i > 0 && _stream->buffer[i-1] == '\r')
				_stream->w_buffer[i-1] = '\0';
			else
				_stream->w_buffer[i] = '\0';
			ret_buf = (char *) _stream->w_buffer + _stream->skip;

			i++;
			stream->v_offset += i - _stream->skip;
			_stream->skip = i;
                        break;
		}
	}

	_stream->cr_lookup_pos = i;
        return ret_buf;
}

const unsigned char *i_stream_get_data(IStream *stream, size_t *size)
{
	_IStream *_stream = stream->real_stream;

	if (_stream->skip >= _stream->pos) {
		*size = 0;
		return NULL;
	}

        *size = _stream->pos - _stream->skip;
        return _stream->buffer + _stream->skip;
}

unsigned char *i_stream_get_modifyable_data(IStream *stream, size_t *size)
{
	_IStream *_stream = stream->real_stream;

	if (_stream->skip >= _stream->pos || _stream->w_buffer == NULL) {
		*size = 0;
		return NULL;
	}

        *size = _stream->pos - _stream->skip;
        return _stream->w_buffer + _stream->skip;
}

int i_stream_read_data(IStream *stream, const unsigned char **data,
		       size_t *size, size_t threshold)
{
	_IStream *_stream = stream->real_stream;
	ssize_t ret = 0;

	while (_stream->pos - _stream->skip <= threshold) {
		/* we need more data */
		ret = _stream->read(_stream);
		if (ret < 0)
			break;
	}

	*data = i_stream_get_data(stream, size);
	return *size > threshold ? 1 :
		ret == -2 ? -2 :
		*size > 0 ? 0 : -1;
}

IStream *_i_stream_create(_IStream *_stream, Pool pool, int fd,
			  uoff_t start_offset, uoff_t v_size)
{
	_stream->fd = fd;
	_stream->istream.start_offset = start_offset;
	_stream->istream.v_size = v_size;
	_stream->istream.v_limit = v_size;
	_stream->istream.real_stream = _stream;

	_io_stream_init(pool, &_stream->iostream);
	return &_stream->istream;
}

--- NEW FILE: istream.h ---
#ifndef __ISTREAM_H
#define __ISTREAM_H

struct _IStream {
	uoff_t start_offset;
	uoff_t v_offset, v_size, v_limit; /* relative to start_offset */

	int stream_errno;
	unsigned int closed:1;

	void *real_stream;
};

IStream *i_stream_create_file(int fd, Pool pool, size_t max_buffer_size,
			      int autoclose_fd);
IStream *i_stream_create_mmap(int fd, Pool pool, size_t block_size,
			      uoff_t start_offset, uoff_t v_size,
			      int autoclose_fd);
IStream *i_stream_create_from_data(Pool pool, const unsigned char *data,
				   size_t size);

/* Reference counting. References start from 1, so calling i_stream_unref()
   destroys the stream if i_stream_ref() is never used. */
void i_stream_ref(IStream *stream);
void i_stream_unref(IStream *stream);

/* Return file descriptor for stream, or -1 if none is available. */
int i_stream_get_fd(IStream *stream);

/* Mark the stream closed. Any reads after this will return -1. The data
   already read can still be used. */
void i_stream_close(IStream *stream);

/* Change the maximum size for stream's input buffer to grow. Useful only
   for buffered streams (currently only file). */
void i_stream_set_max_buffer_size(IStream *stream, size_t max_size);
/* Change the start_offset and drop all data in buffers. Doesn't do anything
   if offset is the same as existing start_offset. */
void i_stream_set_start_offset(IStream *stream, uoff_t offset);
/* Stream won't be read past specified offset. Giving 0 as offset
   removes the limit. */
void i_stream_set_read_limit(IStream *stream, uoff_t v_offset);
/* Makes reads blocking until at least one byte is read. timeout_func is
   called if nothing is read in specified time. Setting timeout_msecs to 0
   makes it non-blocking. This call changes non-blocking state of file
   descriptor. */
void i_stream_set_blocking(IStream *stream, int timeout_msecs,
			   void (*timeout_func)(void *), void *context);

/* Returns number of bytes read if read was ok, -1 if EOF or error, -2 if the
   input buffer is full. */
ssize_t i_stream_read(IStream *stream);
/* Skip forward a number of bytes. Never fails, the next read tells if it
   was successful. */
void i_stream_skip(IStream *stream, uoff_t count);
/* Seek to specified position from beginning of file. Never fails, the next
   read tells if it was successful. This works only for files. */
void i_stream_seek(IStream *stream, uoff_t v_offset);
/* Reads the next line from stream and returns it, or NULL if more data is
   needed to make a full line. NOTE: modifies the data in buffer for the \0,
   so it works only with buffered streams (currently only file). */
char *i_stream_next_line(IStream *stream);
/* Returns pointer to beginning of read data, or NULL if there's no data
   buffered. */
const unsigned char *i_stream_get_data(IStream *stream, size_t *size);
/* Like i_stream_get_data(), but returns non-const data. This only works with
   buffered streams (currently only file), others return NULL. */
unsigned char *i_stream_get_modifyable_data(IStream *stream, size_t *size);
/* Like i_stream_get_data(), but read more when needed. Returns 1 if more
   than threshold bytes are available, 0 if less, -1 if error or EOF with no
   bytes available, or -2 if stream's input buffer is full. */
int i_stream_read_data(IStream *stream, const unsigned char **data,
		       size_t *size, size_t threshold);

#endif

--- NEW FILE: ostream-file.c ---
/*
   ostream-file.c : Output stream handling for files

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "alarm-hup.h"
#include "ioloop.h"
#include "network.h"
#include "sendfile-util.h"
#include "istream.h"
#include "ostream-internal.h"

#include <unistd.h>
#ifdef HAVE_SYS_UIO_H
#  include <sys/uio.h>
#endif

#define O_STREAM_MIN_SIZE 4096

#define IS_STREAM_EMPTY(fstream) \
	(!(fstream)->full && (fstream)->head == (fstream)->tail)

#define MAX_SSIZE_T(size) \
	((size) < SSIZE_T_MAX ? (size_t)(size) : SSIZE_T_MAX)

typedef struct {
	_OStream ostream;

	int fd;
	int priority;
	IO io;

	unsigned char *buffer; /* ring-buffer */
	size_t buffer_size, max_buffer_size;
	size_t head, tail; /* first unsent/unused byte */

	int timeout_msecs;
	void (*timeout_func)(void *);
	void *timeout_context;

	unsigned int full:1; /* if head == tail, is buffer empty or full? */
	unsigned int corked:1;
	unsigned int no_socket_cork:1;
	unsigned int autoclose_fd:1;
} FileOStream;

static void stream_closed(FileOStream *fstream)
{
	if (fstream->autoclose_fd && fstream->fd != -1) {
		if (close(fstream->fd) < 0)
			i_error("FileOStream.close() failed: %m");
		fstream->fd = -1;
	}

	if (fstream->io != NULL) {
		io_remove(fstream->io);
		fstream->io = NULL;
	}

	fstream->ostream.ostream.closed = TRUE;
}

static void _close(_IOStream *stream)
{
	FileOStream *fstream = (FileOStream *) stream;

	/* flush output before really closing it */
	o_stream_flush(&fstream->ostream.ostream);

	stream_closed(fstream);
}

static void _destroy(_IOStream *stream)
{
	FileOStream *fstream = (FileOStream *) stream;

	p_free(fstream->ostream.iostream.pool, fstream->buffer);
}

static void _set_max_buffer_size(_IOStream *stream, size_t max_size)
{
	FileOStream *fstream = (FileOStream *) stream;

	fstream->max_buffer_size = max_size;
}

static void _set_blocking(_IOStream *stream, int timeout_msecs,
			  void (*timeout_func)(void *), void *context)
{
	FileOStream *fstream = (FileOStream *) stream;

	fstream->timeout_msecs = timeout_msecs;
	fstream->timeout_func = timeout_func;
	fstream->timeout_context = context;

	net_set_nonblock(fstream->fd, timeout_msecs == 0);

	if (timeout_msecs != 0)
		alarm_hup_init();
}

static void _cork(_OStream *stream)
{
	FileOStream *fstream = (FileOStream *) stream;

	if (!fstream->corked) {
		if (!fstream->no_socket_cork) {
			if (net_set_cork(fstream->fd, TRUE) < 0)
				fstream->no_socket_cork = TRUE;
		}
		fstream->corked = TRUE;
	}
}

static void update_iovec(struct iovec *iov, unsigned int iov_size, size_t size)
{
	while (size > 0) {
		i_assert(iov_size > 0);

		if ((size_t)iov->iov_len <= size) {
			size -= iov->iov_len;
			iov->iov_base = NULL;
			iov->iov_len = 0;
		} else {
			iov->iov_base = (char *) iov->iov_base + size;
			iov->iov_len -= size;
			size = 0;
		}
		iov++; iov_size--;
	}
}

static void update_buffer(FileOStream *fstream, size_t size)
{
	size_t used;

	if (IS_STREAM_EMPTY(fstream))
		return;

	if (fstream->head < fstream->tail) {
		/* ...HXXXT... */
		used = fstream->tail - fstream->head;
		fstream->head += I_MIN(used, size);
	} else {
		/* XXXT...HXXX */
		used = fstream->buffer_size - fstream->head;
		if (size > used) {
			size -= used;
			if (size < fstream->tail)
				fstream->head = size;
			else {
				/* whole buffer is sent */
				fstream->head = fstream->tail = 0;
			}
		} else {
			fstream->head += I_MIN(used, size);
		}

		fstream->full = FALSE;
	}

	if (fstream->head == fstream->tail)
		fstream->head = fstream->tail = 0;

	if (fstream->head == fstream->buffer_size)
		fstream->head = 0;
}

/* NOTE: modifies iov */
static ssize_t
o_stream_writev(FileOStream *fstream, struct iovec *iov, int iov_size)
{
	ssize_t ret;

	while (iov->iov_len == 0 && iov_size > 0) {
		iov++;
		iov_size--;
	}

	i_assert(iov_size > 0);

	ret = writev(fstream->fd, iov, iov_size);
	if (ret < 0) {
		if (errno == EAGAIN || errno == EINTR)
			return 0;
		stream_closed(fstream);
		return -1;
	}

	update_iovec(iov, iov_size, ret);
	update_buffer(fstream, ret);
	fstream->ostream.ostream.offset += ret;

	return ret;
}

/* returns how much of vector was used */
static int o_stream_fill_iovec(FileOStream *fstream, struct iovec iov[2])
{
	if (IS_STREAM_EMPTY(fstream))
		return 0;

	if (fstream->head < fstream->tail) {
		iov[0].iov_base = fstream->buffer + fstream->head;
		iov[0].iov_len = fstream->tail - fstream->head;
		return 1;
	} else {
		iov[0].iov_base = fstream->buffer + fstream->head;
		iov[0].iov_len = fstream->buffer_size - fstream->head;
		if (fstream->tail == 0)
			return 1;
		else {
			iov[1].iov_base = fstream->buffer;
			iov[1].iov_len = fstream->tail;
			return 2;
		}
	}
}

static int o_stream_send_blocking(FileOStream *fstream, const void *data,
				  size_t size)
{
	time_t timeout_time;
	struct iovec iov[3];
	int iov_len, first;

	iov_len = o_stream_fill_iovec(fstream, iov);
	if (size > 0) {
		iov[iov_len].iov_base = (void *) data;
		iov[iov_len].iov_len = size;
		iov_len++;
	}

	first = TRUE;

	timeout_time = GET_TIMEOUT_TIME(fstream);
	while (iov[iov_len-1].iov_len != 0) {
		if (first)
			first = FALSE;
		else if (timeout_time > 0 && time(NULL) > timeout_time) {
			/* timeouted */
			if (fstream->timeout_func != NULL)
				fstream->timeout_func(fstream->timeout_context);
			fstream->ostream.ostream.stream_errno = EAGAIN;
			return -1;
		}

		if (o_stream_writev(fstream, iov, iov_len) < 0)
			return -1;
	}

        return 1;
}

static int buffer_flush(FileOStream *fstream)
{
	struct iovec iov[2];
	int iov_len;

	if (!IS_STREAM_EMPTY(fstream)) {
		iov_len = o_stream_fill_iovec(fstream, iov);
		if (o_stream_writev(fstream, iov, iov_len) < 0)
			return -1;

		if (!IS_STREAM_EMPTY(fstream)) {
			if (o_stream_send_blocking(fstream, NULL, 0) < 0)
				return -1;
		}
	}

	return 1;
}

static int _flush(_OStream *stream)
{
	FileOStream *fstream = (FileOStream *) stream;
	int ret;

	ret = buffer_flush(fstream);

	if (fstream->corked) {
		/* remove cork */
		if (!fstream->no_socket_cork) {
			if (net_set_cork(fstream->fd, FALSE) < 0)
				i_error("net_set_cork() failed: %m");
		}
		fstream->corked = FALSE;
	}

	return ret;
}

static size_t get_unused_space(FileOStream *fstream)
{
	if (fstream->head > fstream->tail) {
		/* XXXT...HXXX */
		return fstream->head - fstream->tail;
	} else if (fstream->head < fstream->tail) {
		/* ...HXXXT... */
		return (fstream->buffer_size - fstream->tail) + fstream->head;
	} else {
		/* either fully unused or fully used */
		return fstream->full ? 0 : fstream->buffer_size;
	}
}

static int _have_space(_OStream *stream, size_t size)
{
	FileOStream *fstream = (FileOStream *) stream;
	size_t unused;

	if (fstream->max_buffer_size == 0)
		return 1;

	unused = get_unused_space(fstream);
	if (size <= unused)
		return 1;

	unused += (fstream->max_buffer_size - fstream->buffer_size);
	return size <= unused ? 1 : 0;
}

static int _seek(_OStream *stream, uoff_t offset)
{
	FileOStream *fstream = (FileOStream *) stream;
	off_t ret;

	if (offset > OFF_T_MAX) {
		stream->ostream.stream_errno = EINVAL;
		return -1;
	}

	ret = lseek(fstream->fd, (off_t)offset, SEEK_SET);
	if (ret < 0) {
		stream->ostream.stream_errno = errno;
		return -1;
	}

	if (ret != (off_t)offset) {
		stream->ostream.stream_errno = EINVAL;
		return -1;
	}

	stream->ostream.stream_errno = 0;
	stream->ostream.offset = offset;
	return 1;
}

static void o_stream_grow_buffer(FileOStream *fstream, size_t bytes)
{
	size_t size, head_size;

	size = nearest_power(fstream->buffer_size + bytes);
	if (fstream->max_buffer_size != 0) {
		if (size > fstream->max_buffer_size) {
			/* limit the size */
			size = fstream->max_buffer_size;
		} else if (fstream->corked) {
			/* use the largest possible buffer with corking */
			size = fstream->max_buffer_size;
		}
	}

	if (size == fstream->buffer_size)
		return;

	fstream->buffer = p_realloc(fstream->ostream.iostream.pool,
				    fstream->buffer, size);

	if (fstream->tail <= fstream->head && !IS_STREAM_EMPTY(fstream)) {
		head_size = I_MIN(fstream->head, size - fstream->buffer_size);
		memcpy(fstream->buffer + fstream->buffer_size, fstream->buffer,
		       head_size);

		if (head_size == fstream->head)
			fstream->tail = fstream->buffer_size + head_size;
		else {
			memmove(fstream->buffer, fstream->buffer + head_size,
				fstream->head - head_size);
			fstream->tail = fstream->head - head_size;
		}
	}

	fstream->full = FALSE;
	fstream->buffer_size = size;
}

static void stream_send_io(void *context, int fd __attr_unused__,
			   IO io __attr_unused__)
{
	FileOStream *fstream = context;
	struct iovec iov[2];
	int iov_len;

	iov_len = o_stream_fill_iovec(fstream, iov);

	if (iov_len == 0 || o_stream_writev(fstream, iov, iov_len) < 0 ||
	    iov[iov_len-1].iov_len == 0) {
		/* error / all sent */
		io_remove(fstream->io);
                fstream->io = NULL;
	}
}

static size_t o_stream_add(FileOStream *fstream, const void *data, size_t size)
{
	size_t unused, sent;
	int i;

	unused = get_unused_space(fstream);
	if (unused < size)
		o_stream_grow_buffer(fstream, size-unused);

	sent = 0;
	for (i = 0; i < 2 && sent < size && !fstream->full; i++) {
		unused = fstream->tail >= fstream->head ?
			fstream->buffer_size - fstream->tail :
			fstream->head - fstream->tail;

		if (unused > size-sent)
			unused = size-sent;
		memcpy(fstream->buffer + fstream->tail, data, unused);
		sent += unused;

		fstream->tail += unused;
		if (fstream->tail == fstream->buffer_size)
			fstream->tail = 0;

		if (fstream->head == fstream->tail)
			fstream->full = TRUE;
	}

	if (sent != 0 && fstream->io == NULL && !fstream->corked) {
		fstream->io = io_add_priority(fstream->fd, fstream->priority,
					      IO_WRITE, stream_send_io,
					      fstream);
	}

	i_assert(!STREAM_IS_BLOCKING(fstream) || sent == size);
	return sent;
}

static ssize_t _send(_OStream *stream, const void *data, size_t size)
{
	FileOStream *fstream = (FileOStream *) stream;
	struct iovec iov;
	ssize_t ret;

	i_assert(size <= SSIZE_T_MAX);

	if (stream->ostream.closed)
		return -1;

	stream->ostream.stream_errno = 0;

	/* never try sending immediately if fd is blocking,
	   so we don't need to deal with timeout issues here */
	if (IS_STREAM_EMPTY(fstream) && !STREAM_IS_BLOCKING(fstream) &&
	    (!fstream->corked || !_have_space(stream, size))) {
		iov.iov_base = (void *) data;
		iov.iov_len = size;
		ret = o_stream_writev(fstream, &iov, 1);
		if (ret < 0 || (size_t)ret == size)
			return ret;

		data = (const char *) data + ret;
		size -= ret;
	}

	if (!_have_space(stream, size) && STREAM_IS_BLOCKING(fstream)) {
		/* send it blocking */
		if (o_stream_send_blocking(fstream, data, size) < 0)
			return -1;
		return (ssize_t)size;
	} else {
		/* buffer it, at least partly */
		return (ssize_t)o_stream_add(fstream, data, size);
	}
}

static off_t io_stream_sendfile(_OStream *outstream, IStream *instream)
{
	FileOStream *foutstream = (FileOStream *) outstream;
	time_t timeout_time;
	uoff_t start_offset;
	uoff_t offset, send_size;
	ssize_t ret;
	int in_fd, first;

	in_fd = i_stream_get_fd(instream);
	if (in_fd == -1) {
		outstream->ostream.stream_errno = EINVAL;
		return -1;
	}

	/* set timeout time before flushing existing buffer which may block */
	timeout_time = GET_TIMEOUT_TIME(foutstream);
        start_offset = instream->v_offset;

	/* flush out any data in buffer */
	if (buffer_flush(foutstream) < 0)
		return -1;

	first = TRUE;
	for (;;) {
		if (first)
			first = FALSE;
		else if (timeout_time > 0 && time(NULL) > timeout_time) {
			/* timeouted */
			if (foutstream->timeout_func != NULL) {
				foutstream->timeout_func(
					foutstream->timeout_context);
			}
			outstream->ostream.stream_errno = EAGAIN;
			return -1;
		}

		offset = instream->start_offset + instream->v_offset;
		send_size = instream->v_limit - instream->v_offset;

		ret = safe_sendfile(foutstream->fd, in_fd, &offset,
				    MAX_SSIZE_T(send_size));
		if (ret < 0) {
			if (errno != EINTR && errno != EAGAIN) {
				outstream->ostream.stream_errno = errno;
				if (errno != EINVAL) {
					/* close only if error wasn't because
					   sendfile() isn't supported */
					stream_closed(foutstream);
				}
				return -1;
			}

			if (!STREAM_IS_BLOCKING(foutstream)) {
				/* don't block */
				break;
			}
			ret = 0;
		}

		i_stream_skip(instream, (size_t)ret);
		outstream->ostream.offset += ret;

		if ((uoff_t)ret == send_size) {
			/* yes, all sent */
			break;
		}
	}

	return (off_t) (instream->v_offset - start_offset);
}

static off_t io_stream_copy(_OStream *outstream, IStream *instream)
{
	FileOStream *foutstream = (FileOStream *) outstream;
	time_t timeout_time;
	uoff_t start_offset;
	struct iovec iov[3];
	int iov_len;
	const unsigned char *data;
	size_t size;
	ssize_t ret;
	int pos;

	timeout_time = GET_TIMEOUT_TIME(foutstream);
	iov_len = o_stream_fill_iovec(foutstream, iov);

        start_offset = instream->v_offset;
	for (;;) {
		(void)i_stream_read_data(instream, &data, &size,
					 O_STREAM_MIN_SIZE-1);

		if (size == 0) {
			/* all sent */
			break;
		}

		pos = iov_len++;
		iov[pos].iov_base = (void *) data;
		iov[pos].iov_len = size;

		ret = o_stream_writev(foutstream, iov, iov_len);
		if (ret < 0) {
			/* error */
			return -1;
		}

		if (ret == 0 && !STREAM_IS_BLOCKING(foutstream)) {
			/* don't block */
			break;
		}

		if (timeout_time > 0 && time(NULL) > timeout_time) {
			/* timeouted */
			if (foutstream->timeout_func != NULL) {
				foutstream->timeout_func(
					foutstream->timeout_context);
			}
			outstream->ostream.stream_errno = EAGAIN;
			return -1;
		}

		i_stream_skip(instream, size - iov[pos].iov_len);
		iov_len--;

		/* if we already sent the iov[0] and iov[1], we
		   can just remove them from future calls */
		while (iov_len > 0 && iov[0].iov_len == 0) {
			iov[0] = iov[1];
			if (iov_len > 1) iov[1] = iov[2];
			iov_len--;
		}
	}

	return (off_t) (instream->v_offset - start_offset);
}

static off_t _send_istream(_OStream *outstream, IStream *instream)
{
	off_t ret;

	i_assert(instream->v_limit <= OFF_T_MAX);
	i_assert(instream->v_offset <= instream->v_limit);

	if (instream->v_offset == instream->v_limit)
		return 0;

	ret = io_stream_sendfile(outstream, instream);
	if (ret >= 0 || outstream->ostream.stream_errno != EINVAL)
		return ret;

	/* sendfile() not supported (with this fd), fallback to
	   regular sending */

	outstream->ostream.stream_errno = 0;
	return io_stream_copy(outstream, instream);
}

OStream *o_stream_create_file(int fd, Pool pool, size_t max_buffer_size,
			      int priority, int autoclose_fd)
{
	FileOStream *fstream;

	fstream = p_new(pool, FileOStream, 1);
	fstream->fd = fd;
	fstream->priority = priority;
	fstream->max_buffer_size = max_buffer_size;
	fstream->autoclose_fd = autoclose_fd;

	fstream->ostream.iostream.close = _close;
	fstream->ostream.iostream.destroy = _destroy;
	fstream->ostream.iostream.set_max_buffer_size = _set_max_buffer_size;
	fstream->ostream.iostream.set_blocking = _set_blocking;

	fstream->ostream.cork = _cork;
	fstream->ostream.flush = _flush;
	fstream->ostream.have_space = _have_space;
	fstream->ostream.seek = _seek;
	fstream->ostream.send = _send;
	fstream->ostream.send_istream = _send_istream;

	return _o_stream_create(&fstream->ostream, pool);
}

--- NEW FILE: ostream-internal.h ---
#ifndef __OSTREAM_INTERNAL_H
#define __OSTREAM_INTERNAL_H

#include "ostream.h"
#include "iostream-internal.h"

typedef struct __OStream _OStream;

struct __OStream {
/* inheritance: */
	_IOStream iostream;

/* methods: */
	void (*cork)(_OStream *stream);
	int (*flush)(_OStream *stream);
	int (*have_space)(_OStream *stream, size_t size);
	int (*seek)(_OStream *stream, uoff_t offset);
	ssize_t (*send)(_OStream *stream, const void *data, size_t size);
	off_t (*send_istream)(_OStream *outstream, IStream *instream);

/* data: */
	OStream ostream;
};

OStream *_o_stream_create(_OStream *_stream, Pool pool);

#endif

--- NEW FILE: ostream.c ---
/*
   ostream.c : Output stream handling

    Copyright (c) 2002 Timo Sirainen

    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be
    included in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#include "lib.h"
#include "istream.h"
#include "ostream-internal.h"

void o_stream_ref(OStream *stream)
{
	_io_stream_ref(stream->real_stream);
}

void o_stream_unref(OStream *stream)
{
	_io_stream_unref(stream->real_stream);
}

void o_stream_close(OStream *stream)
{
	_io_stream_close(stream->real_stream);
	stream->closed = TRUE;
}

void o_stream_set_max_buffer_size(OStream *stream, size_t max_size)
{
	_io_stream_set_max_buffer_size(stream->real_stream, max_size);
}

void o_stream_set_blocking(OStream *stream, int timeout_msecs,
			   void (*timeout_func)(void *), void *context)
{
	_io_stream_set_blocking(stream->real_stream, timeout_msecs,
				timeout_func, context);
}

void o_stream_cork(OStream *stream)
{
	_OStream *_stream = stream->real_stream;

	if (stream->closed)
		return;

	_stream->cork(_stream);
}

int o_stream_flush(OStream *stream)
{
	_OStream *_stream = stream->real_stream;

	if (stream->closed)
		return -1;

	return _stream->flush(_stream);
}

int o_stream_have_space(OStream *stream, size_t size)
{
	_OStream *_stream = stream->real_stream;

	return _stream->have_space(_stream, size);
}

int o_stream_seek(OStream *stream, uoff_t offset)
{
	_OStream *_stream = stream->real_stream;

	if (stream->closed)
		return -1;

	return _stream->seek(_stream, offset);
}

ssize_t o_stream_send(OStream *stream, const void *data, size_t size)
{
	_OStream *_stream = stream->real_stream;

	if (stream->closed)
		return -1;

	if (size == 0)
		return 0;

	return _stream->send(_stream, data, size);
}

off_t o_stream_send_istream(OStream *outstream, IStream *instream)
{
	_OStream *_outstream = outstream->real_stream;

	if (outstream->closed || instream->closed)
		return -1;

	return _outstream->send_istream(_outstream, instream);
}

OStream *_o_stream_create(_OStream *_stream, Pool pool)
{
	_stream->ostream.real_stream = _stream;

	_io_stream_init(pool, &_stream->iostream);
	return &_stream->ostream;
}

--- NEW FILE: ostream.h ---
#ifndef __OSTREAM_H
#define __OSTREAM_H

struct _OStream {
	uoff_t offset;

	int stream_errno;
	unsigned int closed:1;

	void *real_stream;
};

OStream *o_stream_create_file(int fd, Pool pool, size_t max_buffer_size,
			      int priority, int autoclose_fd);

/* Reference counting. References start from 1, so calling o_stream_unref()
   destroys the stream if o_stream_ref() is never used. */
void o_stream_ref(OStream *stream);
void o_stream_unref(OStream *stream);

/* Mark the stream closed. Nothing will be sent after this call. */
void o_stream_close(OStream *stream);

/* Change the maximum size for stream's output buffer to grow. */
void o_stream_set_max_buffer_size(OStream *stream, size_t max_size);
/* Stream is made to be flushed out whenever it gets full (assumes max_size
   is already set), ie. writes will never be partial. Also makes any blocking
   writes to fail after specified timeout, calling timeout_func if it's
   set. This call changes non-blocking state of file descriptor. */
void o_stream_set_blocking(OStream *stream, int timeout_msecs,
			   void (*timeout_func)(void *), void *context);

/* Delays sending as far as possible, writing only full buffers. Also sets
   TCP_CORK on if supported. o_stream_flush() removes the cork. */
void o_stream_cork(OStream *stream);
/* Flush the output stream, blocks until everything is sent.
   Returns 1 if ok, -1 if error. */
int o_stream_flush(OStream *stream);
/* Returns 1 if specified amount of data currently fits into stream's output
   buffer, 0 if not. */
int o_stream_have_space(OStream *stream, size_t size);

/* Seek to specified position from beginning of file. This works only for
   files. Returns 1 if successful, -1 if error. */
int o_stream_seek(OStream *stream, uoff_t offset);
/* Returns number of bytes sent or buffered, or -1 if disconnected */
ssize_t o_stream_send(OStream *stream, const void *data, size_t size);
/* Send data from input stream. Returns number of bytes sent, or -1 if error.
   Note that this function may block if either instream or outstream is
   blocking. */
off_t o_stream_send_istream(OStream *outstream, IStream *instream);

#endif

Index: Makefile.am
===================================================================
RCS file: /home/cvs/dovecot/src/lib/Makefile.am,v
retrieving revision 1.18
retrieving revision 1.19
diff -u -d -r1.18 -r1.19
--- Makefile.am	3 Dec 2002 00:13:17 -0000	1.18
+++ Makefile.am	6 Dec 2002 01:09:22 -0000	1.19
@@ -15,11 +15,11 @@
 	hex-binary.c \
 	hostpid.c \
 	imem.c \
-	iobuffer.c \
-	ibuffer.c \
-	ibuffer-data.c \
-	ibuffer-file.c \
-	ibuffer-mmap.c \
+	iostream.c \
+	istream.c \
+	istream-data.c \
+	istream-file.c \
+	istream-mmap.c \
 	ioloop.c \
 	ioloop-poll.c \
 	ioloop-select.c \
@@ -33,8 +33,8 @@
 	mmap-anon.c \
 	mmap-util.c \
 	network.c \
-	obuffer.c \
-	obuffer-file.c \
+	ostream.c \
+	ostream-file.c \
 	primes.c \
 	process-title.c \
 	randgen.c \
@@ -64,9 +64,9 @@
 	hex-binary.h \
 	hostpid.h \
 	imem.h \
-	iobuffer-internal.h \
-	ibuffer.h \
-	ibuffer-internal.h \
+	iostream-internal.h \
+	istream.h \
+	istream-internal.h \
 	ioloop.h \
 	ioloop-internal.h \
 	lib.h \
@@ -76,8 +76,8 @@
 	mempool.h \
 	mmap-util.h \
 	network.h \
-	obuffer.h \
-	obuffer-internal.h \
+	ostream.h \
+	ostream-internal.h \
 	primes.h \
 	process-title.h \
 	randgen.h \

Index: lib.h
===================================================================
RCS file: /home/cvs/dovecot/src/lib/lib.h,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- lib.h	26 Nov 2002 13:07:53 -0000	1.9
+++ lib.h	6 Dec 2002 01:09:22 -0000	1.10
@@ -22,8 +22,8 @@
 typedef struct _Timeout *Timeout;
 
 typedef struct _IPADDR IPADDR;
-typedef struct _IBuffer IBuffer;
-typedef struct _OBuffer OBuffer;
+typedef struct _IStream IStream;
+typedef struct _OStream OStream;
 typedef struct _TempString TempString;
 
 #include "compat.h"

--- ibuffer-data.c DELETED ---

--- ibuffer-file.c DELETED ---

--- ibuffer-internal.h DELETED ---

--- ibuffer-mmap.c DELETED ---

--- ibuffer.c DELETED ---

--- ibuffer.h DELETED ---

--- iobuffer-internal.h DELETED ---

--- iobuffer.c DELETED ---

--- obuffer-file.c DELETED ---

--- obuffer-internal.h DELETED ---

--- obuffer.c DELETED ---

--- obuffer.h DELETED ---