lib-fs: Add fs_file/iter_init_with_event() Use the event for logging critical errors

lib-fs: Add fs_file/iter_init_parent()

lib-fs: Split allocation from fs.iter_init() to a separate fs.iter_alloc()

lib-fs: Split allocation from fs.file_init() to a separate fs.file_alloc()

lib-fs: Added internal fs_metadata_find() helper function

lib-fs: Moved fs_write_stream_abort_parent() to fs-api-private.h Only fs wrapper drivers are supposed to call it.

lib-fs: Added fs_get_nlinks() Although fs_stat() could return this, its caller can't indicate whether it actually wants the link count. Usually fs_stat() is used only to get the file's size. In some backends it's not cheap to get the link count, so adding this function allows the caller to explicitly ask for it.

lib-fs: Added fs_metadata_init_or_clear() helper

lib-fs: Implement all lib-fs functions as wrappers to parent stream.

lib-fs: Added fs_switch_ioloop()

lib-fs: fs_wait_async() can't fail, so make it return void. The individual requests can timeout, but not the waiting itself.

global: unsigned int:1 -> bool:1 perl -i -pe 's/unsigned int ([^,:;]+):1;/bool $1:1;/' **/*.[ch]

lib-fs: Clarified fs_write_stream_abort() API and dropped its _async(). We can't handle an abort after an async fs_write_stream_finish() is already going.

lib-fs: Added asserts to make sure async writes are finished before close

lib-fs: Assert-crash if file's istream isn't closed at fs_file_close() Some backends can't guarantee that the istream stays usable after the file is closed.

lib-fs: Added fs-test backend for helping with creation of fs-wrapper unit tests.

lib-fs: Fixed compiling with some OSes

lib-fs: Track operation timing statistics if enable_timing setting is set.

lib-fs: Added "dict" backend, which is a wrapper to using lib-dict.

lib-fs: Moved enum fs_op from fs-randomfail.c to fs-api-private.h These are useful for other purposes as well.

lib-fs: Added "randomfail" driver. Using this in front of fs drivers allows randomly injecting failures. For example: mail_attachment_fs = randomfail:all=10,read=30,read-range=2000-3000:sis posix This means that all FS operations have a 10% chance of failing, except reads have a 30% chance of failing. If the read fails, it'll fail somewhere between offsets 2000-3000 (the default is 0, so it'll fail at the start of file). The supported operations are: wait metadata prefetch read write lock exists stat copy rename delete iter. "all" applies to all of them. The supported ranges are: read-range, write-range, iter-range.

lib-fs: Fixed fs-compress code to actually build and run. It's a plugin (because it depends on extra compression libraries). We want to register it only when it's explicitly attempted to be used, not before.

lib-fs: Added fs-compress wrapper. Future TODO could include automatically detecting the format of the input file, but this should be optional.

lib-fs: Added fs_ref() and fs_unref() for reference counting.

lib-fs: fs_class_register() can now be called externally.

lib-fs: Added support for module_contexts in fs. They could also be added to fs_file if needed, but for now I didn't bother adding it.

lib-fs: Minor code cleanup: Merge read_counted & prefetch_counted into read_or_prefetch_counted

lib-fs: Track how many different operations have been done on the fs.

lib-fs: struct fs_file's write_pending is a flag Signed-off-by: Phil Carmody <phil@dovecot.fi>

lib-fs: Keep track of all fs_iters in fs.

lib-fs: Added wait_ioloop/prev_ioloop helpers to struct fs.

lib-fs: Keep a linked list of all files within fs to help debugging.

lib-fs: Added FS_PROPERTY_COPY_METADATA and fs_set_metadata() tracking.

lib-fs: Added username and session_id to struct fs directly.

lib-fs: Added support for asynchronous fs iteration.

lib-fs: Added support for giving a hash of the written data to be verified by storage.

lib-fs: Added fs_file_close() to explicitly close all streams that the file has open.

lib-fs: Always keep the error in the parentmost fs. This fixes problems with getting the correct error message when wrapper filesystems are used.

lib-fs: If fs_read_stream() creates a seekable stream, keep it open for future reads.

lib-fs: Added FS_OPEN_FLAG_SEEKABLE. Globally handle fs_read_stream() seekability and waits.

lib-fs: Added "metawrap" wrapper to implement metadata as headers in the file content.

lib-fs: fs_file_path() is now a virtual function. This fixes it returning the correct filename when file was created using FS_OPEN_MODE_CREATE_UNIQUE_128 and a wrapper fs.

lib-fs: Added flags to iteration, and FS_ITER_FLAG_DIRS as the first flag.

lib-fs: Added a default fs_read() implementation using the fs_read_stream().

lib-fs: Added a default fs_write() implementation using the fs_write_stream*().

lib-fs: Automatically try to load missing driver as plugin.

lib-fs: fs_wait_async() can now return an error.

lib-fs API cleanups and improvements

lib-fs: fs_init() API changed to allow returning an error.

Added lib-fs for simple filesystem accessing. Implemented POSIX, SiS and SiS-queue backends.