`EACCES` is returned if the file mode bit (i.e., user/group/other rwx
bits) disallow access. `EPERM` is returned if something else denies
access (immutable bit, SELinux, capabilities, etc). This somewhat subtle
no-access distinction is part of POSIX. For now map both to
`error.PermissionDenied` to keep the error signature unchanged. See
duopoly.
This PR is effecitvely an update/simplification of PR #19193.
Tested locally with an immutable file.
Fixes#22733 and #19162.
Four tests in lib/std/posix/test.zig were disabled because they created
fixed-name files in the current working directory, and this caused
problems if tests were running in parallel with other build's tests.
This PR fixes those tests to all use `std.testing.tmpDir` to create unique
temporary names and directories.
Also clean the tests up to more consistently use `defer` to clean up, or
to just rely on tmpDir cleanup to remove individual files.
Working on these tests revealed a bunch of stale WASI code paths in
posix.zig, fixed by replacing stale `wast.AT.FDCWD` references with just
`AT.FDCWD`.
Fixes#14968.
Functions like isMinGW() and isGnuLibC() have a good reason to exist: They look
at multiple components of the target. But functions like isWasm(), isDarwin(),
isGnu(), etc only exist to save 4-8 characters. I don't think this is a good
enough reason to keep them, especially given that:
* It's not immediately obvious to a reader whether target.isDarwin() means the
same thing as target.os.tag.isDarwin() precisely because isMinGW() and similar
functions *do* look at multiple components.
* It's not clear where we would draw the line. The logical conclusion before
this commit would be to also wrap Arch.isX86(), Os.Tag.isSolarish(),
Abi.isOpenHarmony(), etc... this obviously quickly gets out of hand.
* It's nice to just have a single correct way of doing something.
Zig's copy of the `SYMLINK_{NO,}FOLLOW` constants from wasi-musl was
wrong, as were the `IFIFO` and `IFSOCK` file type flags. Fix these up,
and add comments pointing to exactly where they come from (as the
wasi-musl source has lots of unused, different definitions of these
constants).
Add tests for the Zig convention that WASM preopen 3 is the current
working directory. This is true for WASM with or without libc.
Enable several fs and posix tests that are now passing (not necessarily
because of this change) on wasm targets.
Fixes#20890.
* fix merge conflicts
* rename the declarations
* reword documentation
* extract FixedBufferAllocator to separate file
* take advantage of locals
* remove the assertion about max alignment in Allocator API, leaving it
Allocator implementation defined
* fix non-inline function call in start logic
The GeneralPurposeAllocator implementation is totally broken because it
uses global state but I didn't address that in this commit.
heap.zig: define new default page sizes
heap.zig: add min/max_page_size and their options
lib/std/c: add miscellaneous declarations
heap.zig: add pageSize() and its options
switch to new page sizes, especially in GPA/stdlib
mem.zig: remove page_size
This was done by regex substitution with `sed`. I then manually went
over the entire diff and fixed any incorrect changes.
This diff also changes a lot of `callconv(.C)` to `callconv(.c)`, since
my regex happened to also trigger here. I opted to leave these changes
in, since they *are* a correct migration, even if they're not the one I
was trying to do!
The previous commit cast doubt upon the initial report about macOS
kernel behavior, identifying another reason that ENOENT could be
returned from file creation.
However, it is demonstrable that ENOENT can be returned for both cases:
1. create file race
2. handle refers to deleted directory
This commit re-introduces the workaround for the file creation race on
macOS however it does not unconditionally retry - it first tries again
with O_EXCL to disambiguate the error condition that has occurred.
Previous commits
2b0929929d67e222ca6a9523a3a594ed456c4a51
4ea2f441df36cec61e1017f4d795d4037326c98c
had this text:
> There are no dir components, so you would think that this was
> unreachable, however we have observed on macOS two processes racing to
> do openat() with O_CREAT manifest in ENOENT.
This appears to have been a misunderstanding based on the issue
report #12138 and corresponding PR #12139 in which the steps to
reproduce removed the cache directory in a loop which also executed
detached Zig compiler processes.
There is no evidence for the macOS kernel bug however the ENOENT is
easily explained by the removal of the cache directory.
This commit reverts those commits, ultimately reporting the ENOENT as an
error rather than repeating the create file operation. However this
commit also adds an explicit error set to `std.Build.Cache.hit` as well
as changing the `failed_file_index` to a proper diagnostic field that
fully communicates what failed, leading to more informative error
messages on failure to check the cache.
The equivalent failure when occuring for AstGen performs a fatal process
kill, reasoning being that the compiler has an invariant of the cache
directory not being yanked out from underneath it while executing. This
could be made a more granular error in the future but I suspect such
thing is not valuable to pursue.
Related to #18340 but does not solve it.
* Added error message 'ProcessNotFound' for reading and writing in a Linux
process.
This error occurs if the process to be read from or written to no longer exists.
Fixes#19875
* Added error message "ProcessNotFound" for error forwarding.
* Add error messgae for forwarding.
* Added message for forwarding.
* Error set completed.
* Fixed format error.
* Changed comments to doc comments.
The compiler actually doesn't need any functional changes for this: Sema
does reification based on the tag indices of `std.builtin.Type` already!
So, no zig1.wasm update is necessary.
This change is necessary to disallow name clashes between fields and
decls on a type, which is a prerequisite of #9938.
The signature is documented as:
int link(const char *, const char *);
(see https://man7.org/linux/man-pages/man2/link.2.html or https://man.netbsd.org/link.2)
And its not some Linux extension, the [syscall
implementation](21b136cc63/fs/namei.c (L4794-L4797))
only expects two arguments too.
It probably *should* have a flags parameter, but its too late now.
I am a bit surprised that linking glibc or musl against code that invokes
a 'link' with three parameters doesn't fail (at least, I couldn't get any
local test cases to trigger a compile or link error).
The test case in std/posix/test.zig is currently disabled, but if I
manually enable it, it works with this change.
Contributes to #15607
Although the case is not handled in `openatWasi` (as I could not get a
working wasi environment to test the change) I have added a FIXME
addressing it and linking to the issue.
PR https://github.com/ziglang/zig/pull/20679 ("std.c reorganization")
switched feature-detection code to use "T != void" checks in place of
"@hasDecl". However, the std.posix.system struct is empty, so
compile-time feature detection against symbols in there (specifically
`std.posix.system.ucontext_t` in this case), fail at compile time on
freestanding targets.
This PR adds a void ucontext_t into the std.posix.system default.
This PR also adds pseudo-"freestanding" variation of the StackIterator
"unwind" test. It is sort of hacky (its freestanding, but assumes it can
invoke a Linux exit syscall), but it does detect this problem.
Fixes#20710
