Fix wrong order of TRACE arguments.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170707152918.23086-8-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
We are going to switch from TRACE macro to trace points,
this TRACE complicates things, this patch simplifies it.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170707152918.23086-7-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Error is propagated to the caller, TRACE is not needed.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707152918.23086-6-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707152918.23086-5-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Move to modern errp scheme from just LOGging errors.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170707152918.23086-4-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Combine two successive "if (oldStyle) {...} else {...}" into one.
Block "if (client->tlscreds)" under "if (oldStyle)" is unreachable,
as we have "oldStyle = client->exp != NULL && !client->tlscreds;".
So, delete this block.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20170707152918.23086-3-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Separate the case when a client sends NBD_OPT_ABORT from all other
errors. It will be needed for the following patch, where errors will be
reported.
This particular case is not actually an error - it honestly follows the
NBD protocol. Therefore it should not be reported like an error.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707152918.23086-2-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
We are promising more than just odd fixes, and Paolo is hoping
to offload the pull requests to me. Also, enough of NBD is related
to the block layer that it is worth including qemu-block on patches.
While at it, include blockdev-nbd.c and qemu-nbd.texi in the set
of maintained files.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20170707182151.29872-1-eblake@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. In the common case, allocation is unlikely to ever use
values that are not naturally sector-aligned, but it is possible
that byte-based values will let us be more precise about allocation
at the end of an unaligned file that can do byte-based access.
Changing the signature of the function to use int64_t *pnum ensures
that the compiler enforces that all callers are updated. For now,
the io.c layer still assert()s that all callers are sector-aligned,
but that can be relaxed when a later patch implements byte-based
block status. Therefore, for the most part this patch is just the
addition of scaling at the callers followed by inverse scaling at
bdrv_is_allocated(). But some code, particularly stream_run(),
gets a lot simpler because it no longer has to mess with sectors.
Leave comments where we can further simplify by switching to
byte-based iterations, once later patches eliminate the need for
sector-aligned operations.
For ease of review, bdrv_is_allocated() was tackled separately.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_is_allocated_above() was relying on intermediate->total_sectors,
which is a field that can have stale contents depending on the value
of intermediate->has_variable_length. An audit shows that we are safe
(we were first calling through bdrv_co_get_block_status() which in
turn calls bdrv_nb_sectors() and therefore just refreshed the current
length), but it's nicer to favor our accessor functions to avoid having
to repeat such an audit, even if it means refresh_total_sectors() is
called more frequently.
Suggested-by: John Snow <jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Manos Pitsidianakis <el13635@mail.ntua.gr>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually moving away from sector-based interfaces, towards
byte-based. In the common case, allocation is unlikely to ever use
values that are not naturally sector-aligned, but it is possible
that byte-based values will let us be more precise about allocation
at the end of an unaligned file that can do byte-based access.
Changing the signature of the function to use int64_t *pnum ensures
that the compiler enforces that all callers are updated. For now,
the io.c layer still assert()s that all callers are sector-aligned
on input and that *pnum is sector-aligned on return to the caller,
but that can be relaxed when a later patch implements byte-based
block status. Therefore, this code adds usages like
DIV_ROUND_UP(,BDRV_SECTOR_SIZE) to callers that still want aligned
values, where the call might reasonbly give non-aligned results
in the future; on the other hand, no rounding is needed for callers
that should just continue to work with byte alignment.
For the most part this patch is just the addition of scaling at the
callers followed by inverse scaling at bdrv_is_allocated(). But
some code, particularly bdrv_commit(), gets a lot simpler because it
no longer has to mess with sectors; also, it is now possible to pass
NULL if the caller does not care how much of the image is allocated
beyond the initial offset. Leave comments where we can further
simplify once a later patch eliminates the need for sector-aligned
requests through bdrv_is_allocated().
For ease of review, bdrv_is_allocated_above() will be tackled
separately.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Change the internal
loop iteration of backups to track by bytes instead of sectors
(although we are still guaranteed that we iterate by steps that
are cluster-aligned).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert another internal
function (no semantic change).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Continue by converting
the public interface to backup jobs (no semantic change), including
a change to CowRequest to track by bytes instead of cluster indices.
Note that this does not change the difference between the public
interface (starting point, and size of the subsequent range) and
the internal interface (starting and end points).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Xie Changlong <xiechanglong@cmss.chinamobile.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Continue by converting an
internal structure (no semantic change), and all references to
tracking progress. Drop a redundant local variable bytes_per_cluster.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now that the last user [mirror_iteration()] has converted to using
bytes, we no longer need a function to round sectors to clusters.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Change the internal
loop iteration of mirroring to track by bytes instead of sectors
(although we are still guaranteed that we iterate by steps that
are both sector-aligned and multiples of the granularity). Drop
the now-unused mirror_clip_sectors().
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert another internal
function, preserving all existing semantics, and adding one more
assertion that things are still sector-aligned (so that conversions
to sectors in mirror_read_complete don't need to round).
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert another internal
function (no semantic change), and add mirror_clip_bytes() as a
counterpart to mirror_clip_sectors(). Some of the conversion is
a bit tricky, requiring temporaries to convert between units; it
will be cleared up in a following patch.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Rather than having a void function that modifies its input
in-place as the output, change the signature to reduce a layer
of indirection and return the result.
Suggested-by: John Snow <jsnow@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Convert another internal
function (no semantic change).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Continue by converting an
internal structure (no semantic change), and all references to the
buffer size.
Add an assertion that our use of s->granularity >> BDRV_SECTOR_BITS
(necessary for interaction with sector-based dirty bitmaps, until
a later patch converts those to be byte-based) does not suffer from
truncation problems.
[checkpatch has a false positive on use of MIN() in this patch]
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Change the internal
loop iteration of committing to track by bytes instead of sectors
(although we are still guaranteed that we iterate by steps that
are sector-aligned).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Start by converting an
internal function (no semantic change).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Change the internal
loop iteration of streaming to track by bytes instead of sectors
(although we are still guaranteed that we iterate by steps that
are sector-aligned).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
stream_complete() skips the work of rewriting the backing file if
the job was cancelled, if data->reached_end is false, or if there
was an error detected (non-zero data->ret) during the streaming.
But note that in stream_run(), data->reached_end is only set if the
loop ran to completion, and data->ret is only 0 in two cases:
either the loop ran to completion (possibly by cancellation, but
stream_complete checks for that), or we took an early goto out
because there is no bs->backing. Thus, we can preserve the same
semantics without the use of reached_end, by merely checking for
bs->backing (and logically, if there was no backing file, streaming
is a no-op, so there is no backing file to rewrite).
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are gradually converting to byte-based interfaces, as they are
easier to reason about than sector-based. Start by converting an
internal function (no semantic change).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Upcoming patches are going to switch to byte-based interfaces
instead of sector-based. Even worse, trace_backup_do_cow_enter()
had a weird mix of cluster and sector indices.
The trace interface is low enough that there are no stability
guarantees, and therefore nothing wrong with changing our units,
even in cases like trace_backup_do_cow_skip() where we are not
changing the trace output. So make the tracing uniformly use
bytes.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The user interface specifies job rate limits in bytes/second.
It's pointless to have our internal representation track things
in sectors/second, particularly since we want to move away from
sector-based interfaces.
Fix up a doc typo found while verifying that the ratelimit
code handles the scaling difference.
Repetition of expressions like 'n * BDRV_SECTOR_SIZE' will be
cleaned up later when functions are converted to iterate over
images by bytes rather than by sectors.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We likely do not want to carry these legacy -drive options along forever.
Let's emit a deprecation warning for the -drive options that have a
replacement with the -device option, so that the (hopefully few) remaining
users are aware of this and can adapt their scripts / behaviour accordingly.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The '-e' and '-6' options to the 'create' & 'convert' commands were
"deprecated" in favour of the more generic '-o' option many years ago:
commit eec77d9e71
Author: Jes Sorensen <Jes.Sorensen@redhat.com>
Date: Tue Dec 7 17:44:34 2010 +0100
qemu-img: Deprecate obsolete -6 and -e options
Except this was never actually a deprecation, which would imply giving
the user a warning while the functionality continues to work for a
number of releases before eventual removal. Instead the options were
immediately turned into an error + exit. Given that the functionality
is already broken, there's no point in keeping these psuedo-deprecation
messages around any longer.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
According to specification:
"'MSWIN4.1' is the recommanded setting, because it is the setting least likely
to cause compatibility problems. If you want to put something else in here,
that is your option, but the result may be that some FAT drivers might not
recognize the volume."
Specification: "FAT: General overview of on-disk format" v1.03, page 9
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Specification: "FAT: General overview of on-disk format" v1.03, page 23
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
FAT12/FAT16 root directory is two sectors in size, which allows only 512 directory entries.
Prevent QEMU startup if too much files exist, instead of overflowing root directory.
Also introduce variable root_entries, which will be required for FAT32.
Fixes: https://bugs.launchpad.net/qemu/+bug/1599539/comments/4
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
More specifically:
- try without numeric-tail only if LFN didn't have invalid short chars
- start at ~1 (instead of ~0)
- handle case if numeric tail is more than one char (ie > 10)
Windows 9x Scandisk doesn't see anymore mismatches between short file names and
long file names for non-ASCII filenames.
Specification: "FAT: General overview of on-disk format" v1.03, page 31
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
More specifically, create short name from filename and change blacklist of
invalid chars to whitelist of valid chars.
Windows 9x also now correctly see long file names of filenames containing a space,
but Scandisk still complains about mismatch between SFN and LFN.
[kwolf: Build fix for this intermediate patch (it included declarations
for variables that are only used in the next patch) ]
Specification: "FAT: General overview of on-disk format" v1.03, pages 30-31
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Assume that input filename is encoded as UTF-8, so correctly create UTF-16 encoding.
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
readdir() doesn't always return . and .. entries at first and in that order.
This leads to not creating them at first in the directory, which raises some
errors on file system checking utilities like MS-DOS Scandisk.
Specification: "FAT: General overview of on-disk format" v1.03, page 25
Fixes: https://bugs.launchpad.net/qemu/+bug/1599539
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Specification: "FAT: General overview of on-disk format" v1.03, pages 11-13
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- offset_to_bootsector is the number of sectors up to FAT bootsector
- offset_to_fat is the number of sectors up to first File Allocation Table
- offset_to_root_dir is the number of sectors up to root directory sector
Replace first_sectors_number - 1 by offset_to_bootsector.
Replace first_sectors_number by offset_to_fat.
Replace faked_sectors by offset_to_rootdir.
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
MODE_FAKED and MODE_RENAMED are not and were never used.
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This was a complete mess. On 2299 indented lines:
- 1329 were with spaces only
- 617 with tabulations only
- 353 with spaces and tabulations
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
- bs->total_sectors is the number of sectors of the whole disk
- s->sector_count is the number of sectors of the FAT partition
This fixes the following assert in qemu-img map:
qemu-img.c:2641: get_block_status: Assertion `nb_sectors' failed.
This also fixes an infinite loop in qemu-img convert.
Fixes: 4480e0f924
Fixes: https://bugs.launchpad.net/qemu/+bug/1599539
Cc: qemu-stable@nongnu.org
Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Without a passthrough status of BDRV_BLOCK_RAW, anything wrapped by
blkdebug appears 100% allocated as data. Better is treating it the
same as the underlying file being wrapped.
Update iotest 177 for the new expected output.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The lone caller that cares about a return of BDRV_BLOCK_RAW
(namely, io.c:bdrv_co_get_block_status) completely replaces the
return value, so there is no point in passing BDRV_BLOCK_DATA.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We document that *file is valid if the return is not an error and
includes BDRV_BLOCK_OFFSET_VALID, but forgot to obey this contract
when a driver (such as blkdebug) lacks a callback. Messed up in
commit 67a0fd2 (v2.6), when we added the file parameter.
Enhance qemu-iotest 177 to cover this, using a sequence that would
print garbage or even SEGV, because it was dererefencing through
uninitialized memory. [The resulting test output shows that we
have less-than-ideal block status from the blkdebug driver, but
that's a separate fix coming up soon.]
Setting *file on all paths that return BDRV_BLOCK_OFFSET_VALID is
enough to fix the crash, but we can go one step further: always
setting *file, even on error, means that a broken caller that
blindly dereferences file without checking for error is now more
likely to get a reliable SEGV instead of randomly acting on garbage,
making it easier to diagnose such buggy callers. Adding an
assertion that file is set where expected doesn't hurt either.
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Most callback commands in qemu-io return 0 to keep the interpreter
loop running, or 1 to quit immediately. However, open_f() just
passed through the return value of openfile(), which has different
semantics of returning 0 if a file was opened, or 1 on any failure.
As a result of mixing the return semantics, we are forcing the
qemu-io interpreter to exit early on any failures, which is rather
annoying when some of the failures are obviously trying to give
the user a hint of how to proceed (if we didn't then kill qemu-io
out from under the user's feet):
$ qemu-io
qemu-io> open foo
qemu-io> open foo
file open already, try 'help close'
$ echo $?
0
In general, we WANT openfile() to report failures, since it is the
function used in the form 'qemu-io -c "$something" no_such_file'
for performing one or more -c options on a single file, and it is
not worth attempting $something if the file itself cannot be opened.
So the solution is to fix open_f() to always return 0 (when we are
in interactive mode, even failure to open should not end the
session), and save the return value of openfile() for command line
use in main().
Note, however, that we do have some qemu-iotests that do 'qemu-io
-c "open file" -c "$something"'; such tests will now proceed to
attempt $something whether or not the open succeeded, the same way
as if the two commands had been attempted in interactive mode. As
such, the expected output for those tests has to be modified. But it
also means that it is now possible to use -c close and have a single
qemu-io command line operate on more than one file even without
using interactive mode. Although the '-c open' action is a subtle
change in behavior, remember that qemu-io is for debugging purposes,
so as long as it serves the needs of qemu-iotests while still being
reasonable for interactive use, it should not be a problem that we
are changing tests to the new behavior.
This has been awkward since at least as far back as commit
e3aff4f, in 2009.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
