Summary:
On Windows, TempFile::create() was prone to failing with permission
denied errors when a process created many tempfiles without providing
a model large enough to accommodate them. There was also a problem
with createUniqueEntity getting into an infinite loop when all names
permitted by the model are in use. This change fixes both of these
problems and adds a unit test for them.
Reviewers: pcc, rnk, zturner
Reviewed By: zturner
Subscribers: inglorion, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D50126
llvm-svn: 338745
Dsymutil's update functionality was broken on Windows because we tried
to rename a file while we're holding open handles to that file. TempFile
provides a solution for this through its keep(Twine) method. This patch
changes dsymutil to make use of that functionality.
Differential revision: https://reviews.llvm.org/D49860
llvm-svn: 338216
FileOutputBuffer creates a temp file and on commit atomically
renames the temp file to the destination file. Sometimes we
want to modify an existing file in place, but still have the
atomicity guarantee. To do this we can initialize the contents
of the temp file from the destination file (if it exists), that
way the resulting FileOutputBuffer can have only selective
bytes modified. Committing will then atomically replace the
destination file as desired.
llvm-svn: 335902
On Windows we've observed that if you open a file, write to it, map it into
memory and close the file handle, the contents of the memory mapping can
sometimes be incorrect. That was what we did when adding an entry to the
ThinLTO cache using the TempFile and MemoryBuffer classes, and it was causing
intermittent build failures on Chromium's ThinLTO bots on Windows. More
details are in the associated Chromium bug (crbug.com/786127).
We can prevent this from happening by keeping a handle to the file open while
the mapping is active. So this patch changes the mapped_file_region class to
duplicate the file handle when mapping the file and close it upon unmapping it.
One gotcha is that the file handle that we keep open must not have been
created with FILE_FLAG_DELETE_ON_CLOSE, as otherwise the operating system
will prevent other processes from opening the file. We can achieve this
by avoiding the use of FILE_FLAG_DELETE_ON_CLOSE altogether. Instead,
we use SetFileInformationByHandle with FileDispositionInfo to manage the
delete-on-close bit. This lets us remove the hack that we used to use to
clear the delete-on-close bit on a file opened with FILE_FLAG_DELETE_ON_CLOSE.
A downside of using SetFileInformationByHandle/FileDispositionInfo as
opposed to FILE_FLAG_DELETE_ON_CLOSE is that it prevents us from using
CreateFile to open the file while the flag is set, even within the same
process. This doesn't seem to matter for almost every client of TempFile,
except for LockFileManager, which calls sys::fs::create_link to create a
hard link from the lock file, and in the process of doing so tries to open
the file. To prevent this change from breaking LockFileManager I changed it
to stop using TempFile by effectively reverting r318550.
Differential Revision: https://reviews.llvm.org/D48051
llvm-svn: 334630
This breaks the OpenFlags enumeration into two separate
enumerations: OpenFlags and CreationDisposition. The first
controls the behavior of the API depending on whether or not
the target file already exists, and is not a flags-based
enum. The second controls more flags-like values.
This yields a more easy to understand API, while also allowing
flags to be passed to the openForRead api, where most of the
values didn't make sense before. This also makes the apis more
testable as it becomes easy to enumerate all the configurations
which make sense, so I've added many new tests to exercise all
the different values.
llvm-svn: 334221
There was only one place in the entire codebase where a non
default value was being passed, and that place was already hidden
in an implementation file. So we can delete the extra parameter
and all existing clients continue to work as they always have,
while making the interface a bit simpler.
Differential Revision: https://reviews.llvm.org/D47789
llvm-svn: 334046
Summary:
Various path functions were not treating paths consisting of slashes
alone consistently. For example, the iterator-based accessors decomposed the
path "///" into two elements: "/" and ".". This is not too bad, but it
is different from the behavior specified by posix:
```
A pathname that contains ***at least one non-slash character*** and that
ends with one or more trailing slashes shall be resolved as if a single
dot character ( '.' ) were appended to the pathname.
```
More importantly, this was different from how we treated the same path
in the filename+parent_path functions, which decomposed this path into
"." and "". This was completely wrong as it lost the information that
this was an absolute path which referred to the root directory.
This patch fixes this behavior by making sure all functions treat paths
consisting of (back)slashes alone the same way as "/". I.e., the
iterator-based functions will just report one component ("/"), and the
filename+parent_path will decompose them into "/" and "".
A slightly controversial topic here may be the treatment of "//". Posix
says that paths beginning with "//" may have special meaning and indeed
we have code which parses paths like "//net/foo/bar" specially. However,
as we were already not being consistent in parsing the "//" string
alone, and any special parsing for it would complicate the code further,
I chose to treat it the same way as longer sequences of slashes (which
are guaranteed to be the same as "/").
Another slight change of behavior is in the parsing of paths like
"//net//". Previously the last component of this path was ".". However,
as in our parsing the "//net" part in this path was the same as the
"drive" part in "c:\" and the next slash was the "root directory", it
made sense to treat "//net//" the same way as "//net/" (i.e., not to add
the extra "." component at the end).
Reviewers: zturner, rnk, dblaikie, Bigcheese
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D45942
llvm-svn: 331876
See r331124 for how I made a list of files missing the include.
I then ran this Python script:
for f in open('filelist.txt'):
f = f.strip()
fl = open(f).readlines()
found = False
for i in xrange(len(fl)):
p = '#include "llvm/'
if not fl[i].startswith(p):
continue
if fl[i][len(p):] > 'Config':
fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
found = True
break
if not found:
print 'not found', f
else:
open(f, 'w').write(''.join(fl))
and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.
No intended behavior change.
llvm-svn: 331184
LLVM_ON_WIN32 is set exactly with MSVC and MinGW (but not Cygwin) in
HandleLLVMOptions.cmake, which is where _WIN32 defined too. Just use the
default macro instead of a reinvented one.
See thread "Replacing LLVM_ON_WIN32 with just _WIN32" on llvm-dev and cfe-dev.
No intended behavior change.
This moves over all uses of the macro, but doesn't remove the definition
of it in (llvm-)config.h yet.
llvm-svn: 331127
Summary:
This commit changes semantics of createUniqueFile and
createTemporaryFile variants that do not return file descriptors.
Previously they only checked if files exist, therefore being subject
to race conditions. Now they will create an empty file to avoid them.
Functions that do not create a file are now called
getPotentiallyUniqueTempFileName and getPotentiallyUniqueFileName.
Reviewers: klimek, bkramer, krasimir, JDevlieghere, espindola
Reviewed By: klimek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36827
llvm-svn: 327851
Without this when lld failed to replace the output file it would leave
the temporary behind. The problem is that the existing logic is
- cancel the delete flag
- rename
We have to cancel first to avoid renaming and then crashing and
deleting the old version. What is missing then is deleting the
temporary file if the rename fails.
This can be an issue on both unix and windows, but I am not sure how
to cause the rename to fail reliably on unix. I think it can be done
on ZFS since it has an ACL system similar to what windows uses, but
adding support for checking that in llvm-lit is probably not worth it.
llvm-svn: 319786
We already allowed keep+discard. It is important to be able to discard
a temporary if a rename fail. It is also convenient as it allows the
use of RAII for discarding.
Allow discarding twice for similar reasons.
llvm-svn: 318867
This requires a small change to TempFile: allowing a discard after a
failed keep.
With this the cache now handles signals and reuses a fd instead of
reopening the file.
llvm-svn: 318322
This just adds a TempFile class and replaces the use in
FileOutputBuffer with it.
The only difference for now is better error handling. Followup work includes:
- Convert other user of temporary files to it.
- Add support for automatically deleting on windows.
- Add a createUnnamed method that returns a potentially unnamed
file. It would be actually unnamed on modern linux and have a
unknown name on windows.
llvm-svn: 318069
This allows clients to avoid an unnecessary fs::status() call on each
directory entry. Because the information returned by FindFirstFileEx
is a subset of the information returned by a regular status() call,
I needed to extract a base class from file_status that contains only
that information.
On my machine, this reduces the time required to enumerate a ThinLTO
cache directory containing 520k files from almost 4 minutes to less
than 2 seconds.
Differential Revision: https://reviews.llvm.org/D38716
llvm-svn: 315378
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
In doing so, clean up the MD5 interface a little. Most
existing users only care about the lower 8 bytes of an MD5,
but for some users that care about the upper and lower,
there wasn't a good interface. Furthermore, consumers
of the MD5 checksum were required to handle endianness
details on their own, so it seems reasonable to abstract
this into a nicer interface that just gives you the right
value.
Differential Revision: https://reviews.llvm.org/D31105
llvm-svn: 298322
Previously which path syntax we supported dependend on what
platform we were compiling LLVM on. While this is normally
desirable, there are situations where we need to be able to
handle a path that we know was generated on a remote host.
Remote debugging, for example, or parsing debug info.
99% of the code in LLVM for handling paths was platform
agnostic and literally just a few branches were gated behind
pre-processor checks, so this changes those sites to use
runtime checks instead, and adds a flag to every path
API that allows one to override the host native syntax.
Differential Revision: https://reviews.llvm.org/D30858
llvm-svn: 298004
This change adds support for functions to set and get file permissions, in a similar manner to the C++17 permissions() function in <filesystem>. The setter uses chmod on Unix systems and SetFileAttributes on Windows, setting the permissions as passed in. The getter simply uses the existing status() function.
Prior to this change, status() would always return an unknown value for the permissions on a Windows file, making it impossible to test the new function on Windows. I have therefore added support for this as well. On Linux, prior to this change, the permissions included the file type, which should actually be accessed via a different member of the file_status class.
Note that on Windows, only the *_write permission bits have any affect - if any are set, the file is writable, and if not, the file is read-only. This is in common with what MSDN describes for their behaviour of std::filesystem::permissions(), and also what boost::filesystem does.
The motivation behind this change is so that we can easily test behaviour on read-only files in LLVM unit tests, but I am sure that others may find it useful in some situations.
Reviewers: zturner, amccarth, aaron.ballman
Differential Revision: https://reviews.llvm.org/D30736
llvm-svn: 297945
We already have a function create_directories() which can create
an entire tree, and remove() which can remove an empty directory,
but we do not have remove_directories() which can remove an entire
tree. This patch adds such a function.
Because removing a directory tree can have dangerous consequences
when the tree contains a directory symlink, the patch here updates
the existing directory_iterator construct to optionally not follow
symlinks (previously it would always follow symlinks). The delete
algorithm uses this flag so that for symlinks, only the links are
removed, and not the targets.
On Windows this is implemented with SHFileOperation, which also
does not recurse into symbolic links or junctions.
Differential Revision: https://reviews.llvm.org/D30676
llvm-svn: 297314
This was originall reverted due to some test failures in
ModuleCache and TestCompDirSymlink. These issues have all
been resolved and the code now passes all tests.
Differential Revision: https://reviews.llvm.org/D30698
llvm-svn: 297300
This deletes LLDB's FileType enumeration and replaces all
users, and all calls to functions that check whether a file
exists etc with corresponding calls to LLVM.
Differential Revision: https://reviews.llvm.org/D30624
llvm-svn: 297116
Windows does not treat `~` as a reference to home directory, so the call
to `llvm::sys::path::native` on, say, `~/somedir` produces `~\somedir`,
which has different meaning than the original path. With this change
tilde is expanded on Windows to user profile directory. Such behavior
keeps original meaning of the path and is consistent with the algorithm
of `llvm::sys::path::home_directory`.
Differential Revision: https://reviews.llvm.org/D27527
llvm-svn: 296590
This is the first part of an effort to add wasm binary
support across all llvm tools.
Patch by Sam Clegg
Differential Revision: https://reviews.llvm.org/D26172
llvm-svn: 288251
This patch makes it possible to identify object files created by CL.exe
with /GL option. Such file contains Microsoft proprietary intermediate
code instead of target machine code to do LTO.
I need this to print out user-friendly error message from LLD.
Differential Revision: https://reviews.llvm.org/D26645
llvm-svn: 286919
/../foo is still a proper path after removing the dotdot. This should
now finally match https://9p.io/sys/doc/lexnames.html [Cleaning names].
llvm-svn: 284384
Darwin added support in its Xcode 8.0 tools (released in the beta) for universal
files where offsets and sizes for the objects are 64-bits to allow support for
objects contained in universal files to be larger then 4gb. The change is very
straight forward. There is a new magic number that differs by one bit, much
like the 64-bit Mach-O files. Then there is a new structure that follow the
fat_header that has the same layout but with the offset and size fields using
64-bit values instead of 32-bit values.
rdar://26899493
llvm-svn: 273207
Summary:
Add support to control where files for a distributed backend (the
individual index files and optional imports files) are created.
This is invoked with a new thinlto-prefix-replace option in the gold
plugin and llvm-lto. If specified, expects a string of the form
"oldprefix:newprefix", and instead of generating these files in the
same directory path as the corresponding bitcode file, will use a path
formed by replacing the bitcode file's path prefix matching oldprefix
with newprefix.
Also add a new replace_path_prefix helper to Path.h in libSupport.
Depends on D19636.
Reviewers: joker.eph
Subscribers: llvm-commits, joker.eph
Differential Revision: http://reviews.llvm.org/D19644
llvm-svn: 269771
at least as big as the mach header to be identified as a Mach-O file and
make sure smaller files are not identified as a Mach-O files but as
unknown files. Also fix identify_magic() so it looks at all 4 bytes of
the filetype field when determining the type of the Mach-O file.
Then fix the macho-invalid-header test case to check that it is an
unknown file and make sure it does not get the error for
object_error::parse_failed. And also update the unit tests.
llvm-svn: 258883
Summary:
The new function sys::path::user_cache_directory tries to discover
a directory suitable for cache storage for current system user.
On Windows and Darwin it returns a path to system-specific user cache directory.
On Linux it follows XDG Base Directory Specification, what is:
- use non-empty $XDG_CACHE_HOME env var,
- use $HOME/.cache.
Reviewers: chapuni, aaron.ballman, rafael
Subscribers: rafael, aaron.ballman, llvm-commits
Differential Revision: http://reviews.llvm.org/D13801
llvm-svn: 251784
This reverts commit 228874. For some reason users reported
seeing Clang taking up 25+GB of memory and bringing down
machines with this change. Reverting until we figure it out.
llvm-svn: 228890
For Windows, filename_pos() tries to find the filename by
searching for separators after the last :. Instead, it should
really check for the only location that a : is valid, which is
in the second character, and search for separators after that.
llvm-svn: 228874
utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
llvm-svn: 225974
The main difference is the removal of
std::error_code exists(const Twine &path, bool &result);
It was an horribly redundant interface since a file not existing is also a valid
error_code. Now we have an access function that returns just an error_code. This
is the only function that has to be implemented for Unix and Windows. The
functions can_write, exists and can_execute an now just wrappers.
One still has to be very careful using these function to avoid introducing
race conditions (Time of check to time of use).
llvm-svn: 217625
We had two functions for finding the temp or cache directory. Each had a
different set of smarts about OS specific APIs.
With this patch system_temp_directory becomes the only way to do it.
llvm-svn: 216460
path::const_iterator claims that it's a bidirectional iterator, but it
doesn't satisfy all of the contracts for a bidirectional iterator.
For example, n3376 24.2.5 p6 says "If a and b are both dereferenceable,
then a == b if and only if *a and *b are bound to the same object",
but this doesn't work with how we stash and recreate Components.
This means that our use of reverse_iterator on this type is invalid
and leads to many of the valgrind errors we're hitting, as explained
by Tilmann Scheller here:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140728/228654.html
Instead, we admit that path::const_iterator is only an input_iterator,
and implement a second input_iterator for path::reverse_iterator (by
changing const_iterator::operator-- to reverse_iterator::operator++).
All of the uses of this just traverse once over the path in one
direction or the other anyway.
llvm-svn: 214737
While std::error_code itself seems to work OK in all platforms, there
are few annoying differences with regards to the std::errc enumeration.
This patch adds a simple llvm enumeration, which will hopefully avoid build
breakages in other platforms and surprises as we get more uses of
std::error_code.
llvm-svn: 210920
The idea of this patch is to turn llvm/Support/system_error.h into a
transitional header that just brings in the erorr_code api to the llvm
namespace. I will remove it shortly afterwards.
The cases where the general idea needed some tweaking:
* std::errc is a namespace in msvc, so we cannot use "using std::errc". I could
add an #ifdef, but there were not that many uses, so I just added std:: to
them in this patch.
* Template specialization had to be moved to the std namespace in this
patch set already.
* The msvc implementation of default_error_condition doesn't seem to
provide the same transformations as we need. Not too surprising since
the standard doesn't actually say what "equivalent" means. I fixed the
problem by keeping our old mapping and using it at error_code
construction time.
Despite these shortcomings I think this is still a good thing. Some reasons:
* The different implementations of system_error might improve over time.
* It removes 925 lines of code from llvm already.
* It removes 6313 bytes from the text segment of the clang binary when
it is built with gcc and 2816 bytes when building with clang and
libstdc++.
llvm-svn: 210687
When using a //net/ path, we were transforming the trailing / into a '.'
when the path was just the root path and we were iterating backwards.
Forwards iteration and other kinds of root path (C:\, /) were already
correct.
llvm-svn: 202999
After this I will set the default back to F_None. The advantage is that
before this patch forgetting to set F_Binary would corrupt a file on windows.
Forgetting to set F_Text produces one that cannot be read in notepad, which
is a better failure mode :-)
llvm-svn: 202052
Before this patch they would take an boolean argument to say if the path
already existed. This was redundant with the returned error_code which is able
to represent that. This allowed for callers to incorrectly check only the
existed flag instead of first checking the error code.
Instead, pass in a boolean flag to say if the previous (non-)existence should be
an error or not.
Callers of the of the old simple versions are not affected. They still ignore
the previous (non-)existence as they did before.
llvm-svn: 201979
This is an optimistic version of create_diretories: it tries to create the
directory first and looks at the parent only if that fails.
Running strace on "mkdir -p" shows that it is pessimistic, calling mkdir on
every element of the path. We could implement that if needed.
In any case, with both strategies there is no reason to call stat, just check
the return of mkdir.
llvm-svn: 201347