Hello,
While experimenting with the `wasm32-wasip2` target and CPython, I
discovered an issue with the `getaddrinfo()` implementation: it fails to
resolve the provided service into a port number, causing `sin_port` to
always be set to 0. This issue leads to failures in network-related
functions that rely on `getaddrinfo()`, such as Python's `urllib3`
library, which passes the result directly to `connect()`. This results
in connection attempts using a port value of 0, which naturally fails.
### Minimal example to reproduce the problem
```c
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
int main(void) {
struct addrinfo *res = NULL;
getaddrinfo("google.com", "443", NULL, &res);
for (struct addrinfo *i = res; i != NULL; i = i->ai_next) {
char str[INET6_ADDRSTRLEN];
if (i->ai_addr->sa_family == AF_INET) {
struct sockaddr_in *p = (struct sockaddr_in *)i->ai_addr;
int port = ntohs(p->sin_port);
printf("%s: %i\n", inet_ntop(AF_INET, &p->sin_addr, str, sizeof(str)), port);
} else if (i->ai_addr->sa_family == AF_INET6) {
struct sockaddr_in6 *p = (struct sockaddr_in6 *)i->ai_addr;
int port = ntohs(p->sin6_port);
printf("%s: %i\n", inet_ntop(AF_INET6, &p->sin6_addr, str, sizeof(str)), port);
}
}
return 0;
}
```
```
$ /opt/wasi-sdk/bin/clang -target wasm32-wasip2 -o foo foo.c
$ wasmtime run -S allow-ip-name-lookup=y foo
216.58.211.238: 0
2a00:1450:4026:808::200e: 0
```
Expected output:
```
216.58.211.238: 443
2a00:1450:4026:808::200e: 443
```
### Root Cause
The root cause is that `getaddrinfo()` does not correctly translate the
provided service into a port number. As described in the `getaddrinfo()`
man [page](https://man7.org/linux/man-pages/man3/getaddrinfo.3.html),
the function should:
> service sets the port in each returned address structure. If
this argument is a service name (see
[services(5)](https://man7.org/linux/man-pages/man5/services.5.html)),
it is
translated to the corresponding port number. This argument can
also be specified as a decimal number, which is simply converted
to binary. If service is NULL, then the port number of the
returned socket addresses will be left uninitialized.
### Proposed Fix
This pull request addresses the issue by implementing the following
behavior for `getaddrinfo()`:
* If the service is `NULL`, the port number in the returned socket
addresses remains uninitialized.
* The value is converted to an integer and validated if the service is
numeric.
The PR does not currently add support for translating named services
into port numbers because `getservbyname()` has not been implemented. In
cases where a named service is provided, the `EAI_NONAME` error code is
returned.
`tms_cutime` is the sum of the user times of child processes *excluding
the current process*. Since WASI doesn't provide a way to spawn a new
process, this value should always be 0.
This implementation never changes actual memory protection, but it does
verify that the address range and flags are valid. The direct motivation
is fixing a linker error where LLVM links to `mprotect` in dead code.
Issue [#8392] in Wasmtime highlights how preopen registration can result
in a hang when compiled for a threaded environment. The problem is that
`internal_register_preopened_fd_unlocked` assumes it will not touch the
global lock because its caller, `__wasilibc_populate_preopens`, already
has taken the lock. Unfortunately, a refactoring in #408 (which
introduces `internal_register_preopened_fd_unlocked`) did not catch that
the `resize` function called internally also takes the global lock. This
change removes that locking in `resize` under the assumption that it
will only be called when the lock is already taken.
[#8392]: https://github.com/bytecodealliance/wasmtime/issues/8392
This resets the preopens table to an uninitialized state, forcing it to be
reinitialized next time it is needed. This is useful when pre-initializing
using e.g. `wizer` or `component-init`. Such tools are capable of taking a
snapshot of a running application which may later be resumed on an unrelated
runtime (which may have its own, unrelated preopens).
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
This also includes stubs for `gethostbyname`, `gethostbyaddr`, etc. which were
necessary to get CPython to build. I believe it will be possible to implement
them all properly at some point, but don't have the bandwidth at the moment.
Finally, this includes a few fixes for issues I missed in earlier PRs that
surfaced when running the CPython `asyncio` test suite.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
This enables `wasm32-wasip2` support for `close`, `poll`, and `pselect`. I
cheated a bit for the latter by re-implementing `pselect` in terms of `poll` to
avoid having to implement wasip2 versions of both.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
This adds `wasm32-wasip2` implementations of `shutdown`, `getsockopt`, and
`setsockopt`. It also extends the existing `ioctl` implementation to handle
both p1 and p2 file descriptors since we can't know until runtime which kind we
have. Once we've moved `wasm32-wasip2` fully to WASI 0.2 and remove the need for
the p1 adapter, we'll be able to switch to separate p1 and p2 `ioctl`
implementations.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
This adds `bind`, `listen`, and `accept` implementations based on
`wasi-sockets` for the `wasm32-wasip2` target.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
* implement basic TCP/UDP client support
This implements `socket`, `connect`, `recv`, `send`, etc. in terms of
`wasi-sockets` for the `wasm32-wasip2` target.
I've introduced a new public header file: `__wasi_snapshot.h`, which will define
a preprocessor symbol `__wasilibc_use_wasip2` if using the `wasm32-wasip2`
version of the header, in which case we provide features only available for that
target.
Co-authored-by: Dave Bakker <github@davebakker.io>
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* fix grammar in __wasi_snapshot.h comment
Co-authored-by: Dan Gohman <dev@sunfishcode.online>
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
---------
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
Co-authored-by: Dan Gohman <dev@sunfishcode.online>
* Start renaming preview1 to p1 and preview2 to p2
This is an initial start at renaming the "preview" terminology in WASI
targets to "pX". For example the `wasm32-wasi` target should transition
to `wasm32-wasip1`, `wasm32-wasi-preview2` should transition to
`wasm32-wasip2`, and `wasm32-wasi-threads` should transition to
`wasm32-wasip1-threads`. This commit applies a few renames in the
`Makefile` such as:
* `WASI_SNAPSHOT` is now either "p1" or "p2"
* The default p2 target triple is now `wasm32-wasip2` instead of
`wasm32-wasi-preview2` (in the hopes that it's early enough to change
the default).
* Bindings for WASIp2 were renamed from "preview2" terminology to "wasip2".
* The expected-defines files are renamed and the logic of which
expectation was used has been updated slightly.
With this commit the intention is that non-preview2 defaults do not
change. For example the default build still produces a `wasm32-wasi`
sysroot. If `TARGET_TRIPLE=wasm32-wasip1` is passed, however, then that
sysroot is produced instead. Similarly a `THREAD_MODEL=posix` build
produces a `wasm32-wasi-threads` sysroot target but you can now also
pass `TARGET_TRIPLE=wasm32-wasip1-threads` to rename the sysroot.
My hope is to integrate this into the wasi-sdk repository and build a
dual sysroot for these new targets for a release or two so both are
supported and then in the future the defaults can be switched away from
`wasm32-wasi` to `wasm32-wasip1` as built-by-default.
* Update builds in CI
* Update test workflow
* Fix test for wasm32-wasip1-threads
* Make github actions rules a bit more readable
* add descriptor table for mapping fds to handles
This introduces `descriptor_table.h` and `descriptor_table.c`, providing a
global hashtable for tracking `wasi-libc`-managed file descriptors.
WASI Preview 2 has no notion of file descriptors and instead uses unforgeable
resource handles. Moreover, there's not necessarily a one-to-one correspondence
between POSIX file descriptors and resource handles (e.g. a TCP connection may
require separate handles for reading, writing, and polling the same connection).
We use this table to map each POSIX descriptor to a set of one or more handles
and any extra state which libc needs to track.
Note that we've added `descriptor_table.h` to the
libc-bottom-half/headers/public/wasi directory, making it part of the public
API. The intention is to give applications access to the mapping, enabling them
to convert descriptors to handles and vice-versa should they need to
interoperate with both libc and WASI directly.
Co-authored-by: Dave Bakker <github@davebakker.io>
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* add dummy fields to otherwise empty structs
The C standard doesn't allow empty structs. Clang doesn't currently complain,
but we might as well stick to the spec in case it becomes more strict in the
future.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* move descriptor_table.h to headers/private
We're not yet ready to commit to making this API public, so we'll make it
private for now.
I've also expanded a comment in descriptor_table.c to explain the current ABI
for resource handles.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* re-run clang-format to fix indentation
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
---------
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Co-authored-by: Dave Bakker <github@davebakker.io>
* make the Makefiles a bit more robust
- Escape "." character in `sed` regex
- Ensure that %.wasm target fails cleanly (i.e. without generating the target file) if `wasm-tools` fails
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* split `component new` rule out of link rule for Preview 2
We now explicitly distinquish between core module files (%.core.wasm) and
component files (%.wasm), which helps avoid the trickery in my previous commit.
In order to test this properly, I needed to update the Wasmtime URL to point to
v17.0.0 instead of dev (which we needed to do anyway), and that in turn required
updating the bindings to use the final WASI 0.2.0 release.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
---------
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Per https://github.com/WebAssembly/wasi-sdk/issues/373, LLVM's libc++ no longer
allows us to enable `<fstream>` and `<filesystem>` separately -- it's both or
neither. Consequently, we either need to patch libc++ to not use `statvfs`,
`chmod`, etc. or add stub functions for those features to `wasi-libc`. Since
we're planning to eventually support those features with WASI Preview 2 and
beyond, it makes sense to do the latter.
Note that since libc++ uses `DT_SOCK`, I've added a definition for it -- even
though WASI Preview 1 does not define it. No Preview 1 file will ever have that
type, so code that handles that type will never be reached, but defining it
allows us to avoid WASI-specific patches to libc++.
Related to `DT_SOCK`, I had to change the `S_IFIFO` value so it does not
conflict with `S_IFSOCK`, thereby avoiding ambiguity in `__wasilibc_iftodt`.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* add WASI Preview 2 bindings
This adds C bindings generated from the `wasi:cli/imports@0.2.0-rc-2023-12-05`
world, plus a makefile target to regenerate them from the WIT source files.
We'll use these bindings to call Preview 2 host functions when building for the
`wasm32-wasi-preview2` target.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* update to pre-release of `wit-bindgen` 0.17.0
This includes https://github.com/bytecodealliance/wit-bindgen/pull/804 (fix
broken indentation in generated code) and
https://github.com/bytecodealliance/wit-bindgen/pull/805 (support overriding
world name and adding a suffix to the component type custom section).
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* test all targets; update preview2 expected output files
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* build for `wasm32-wasi-threads` before testing it
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* move generated bindings per review feedback
Since these files aren't part of cloudlibc, no reason to put them under the
cloudlibc directory.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* move preview2.h to wasi directory
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
---------
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* add shared library support
This adds support for building WASI shared libraries per
https://github.com/WebAssembly/tool-conventions/blob/main/DynamicLinking.md.
For the time being, the goal is to allow "pseudo-dynamic" linking using the
Component Model per
https://github.com/WebAssembly/component-model/blob/main/design/mvp/examples/SharedEverythingDynamicLinking.md.
This requires all libraries to be available when the component is created, but
still allows runtime symbol resolution via `dlopen`/`dlsym` backed by a static
lookup table. This is sufficient to support Python native extensions, for
example. A complete demo using `wit-component` is available at
https://github.com/dicej/component-linking-demo.
This commit adds support for building `libc.so`, `libc++.so`, and `libc++abi.so`
alongside their static counterparts.
Notes:
- I had to refactor `errno` support a bit to avoid a spurious `_ZTH5errno` (AKA "thread-local initialization routine for errno") import in `libc++.so`.
- Long double print and scan are included by default in `libc.so` rather than in a separate library.
- `__main_argc_argv` is now a weak symbol since it's not relevant for reactors.
- `dlopen`/`dlsym` rely on a lookup table provided by the "dynamic" linker via `__wasm_set_libraries`. Not all flags are supported yet, and unrecognized flags will result in an error.
- This requires https://reviews.llvm.org/D153293, which we will need to backport to LLVM 16 until 17 is released. I'll open a `wasi-sdk` PR with that change and various Makefile tweaks to support shared libraries.
- `libc.so` is temporarily disabled for the `wasi-threads` build until someone can make `wasi_thread_start.s` position-independent.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
build `-fPIC` .o files separately from non-`-fPIC` ones
This allows us to build both libc.so and libc.a without incurring indirection
penalties in the latter.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
only build libc.so when explicitly requested
Shared library support in LLVM for non-Emscripten Wasm targets will be added in
version 17, which has not yet been released, so we should not attempt to build
libc.so by default (at least not yet).
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
remove dl.c
I'll open a separate PR for this later.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
update `check-symbols` files
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* generate separate .so files for emulated features
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* revert errno changes in favor of a smaller change
@yamt pointed out there's an easier way to address the `_ZTH5errno` issue I
described in an earlier commit: use `_Thread_local` for both C and C++. This
gives us a simpler ABI and avoids needing to import a thread-local initializer
for `errno` in libc++.so.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* remove redundant `$(OBJDIR)/%.long-double.pic.o` rule in Makefile
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* consolidate libwasi-emulated-*.so into a single library
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* add comment explaining use of `--whole-archive`
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* Revert "remove redundant `$(OBJDIR)/%.long-double.pic.o` rule in Makefile"
This reverts commit dbe2cb10541dd27e4e0ed71d30ce304b9c9133d6.
* move `__main_void` from __main_void.c to crt1-command.c
This and `__main_argc_argv` are only relevant for commands (not reactors), so it
makes sense to scope them accordingly. In addition, the latter was being
imported from libc.so, forcing applications to provide it even if it wasn't
relevant.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* Revert "consolidate libwasi-emulated-*.so into a single library"
This reverts commit c6518223a49f60e4bb254a3e77a411fdade18df2.
* build crt1-*.o with `-fPIC`
This ensures they can be used in a PIE or PIC context.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* ignore `__memory_base` when checking undefined symbols
Whether this symbol appears varies between LLVM versions.
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* Revert "move `__main_void` from __main_void.c to crt1-command.c"
This reverts commit f3038354610b7eb18bfd39092a2ccc3b72842dc4.
* add explanatory comments to __main_void.c
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
* add `__wasilibc_unmodified_upstream` and comment to `__lctrans_cur`
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
---------
Signed-off-by: Joel Dice <joel.dice@fermyon.com>
Given there are already AF_* definitions, and they are (now) essentially
synonyms, we add those definitions to enable compilation of code that
already use PF_* macros.
* Convert preopen initialization to be lazy.
Insteead of eagerly initializing the preopens in a static constructor,
perform preopen initialization the first time it's needed, or before a
close or a renumber which might disrupt the file descriptor space.
And, use a weak symbol with a stub function for use by `close` or
`fd_renumber`, we that they can trigger preopen initialization only
if it's actually needed.
This way, if a program doesn't contain any calls to any function that
needs preopens, it can avoid linking in the preopen initialization code.
And if it contains calls but doesn't execute them at runtime, it can
avoid executing the preopen intiailization code.
A downside here is that this may cause problems for users that call
`__wasi_fd_close` or `__wasi_fd_renumber` directly and close over
overwrite some preopens before libc has a chance to scan them. To
partially address this, this PR does add a declaration for
`__wasilibc_populate_preopens` to <wasi/libc.h> so that users can call
it manually if they need to.
* Fix calling `internal_register_preopened_fd` with the lock held.
Factor out the lock acquisition from the implementation of
`internal_register_preopened_fd` so that we can call it from
`__wasilibc_populate_preopens` with the lock held.
Calling _initialize multiple times is undefined behavior, since the
ctors are not guaranteed to be idempotent. We should have this safety
check which is similar to #329.
When a user calls `open` with a path that does not have a corresponding
preopen, set errno to `ENOENT` rather than `ENOTCAPABLE`. This
conceptually represents an attempt to open a path which has not been
provided within the sandbox, so it's more accurately represented as
"not present" rather than "insufficient capabilities".
as __wasi_errno_t is uint16_t, with the current coding,
__pthread_create will never see negative return values from
wasi:thread_spawn.
eg. (int)(uint16_t)-1 == 65535.
I've now tested the zero-inode path on a Wasm engine specially-modified
to have `fd_readdir` set inode numbers to zero. Fix two bugs this turned up:
- Increment `buffer_processed`, as noticed by @yamt
- Don't do an `fstatat` on "..", because that references a path outside
of the directory, which gets a permission-denied error.
* If `fd_readdir` returns a zero inode, call `fstatat` to get the inode value.
On some systems, `fd_readdir` may not implement the `d_ino` field and
may set it to zero. When this happens, have wasi-libc call `fstatat` to
get the inode number.
See the discussion in
https://github.com/WebAssembly/wasi-filesystem/issues/65 for details.
* Update the `d_type` field too, in case it changes.
This function returns the address of `errno`, which makes it easier to
access from non-C languages since `errno` is a thread-local variable
which requires a special ABI.
* threads: implement init of TLS and stack pointer
* fix: rename wasi_snapshot_preview2_thread_spawn to wasi_thread_spawn
Signed-off-by: Harald Hoyer <harald@profian.com>
* fix: change signature of wasi_thread_start
Signed-off-by: Harald Hoyer <harald@profian.com>
* fix: pthread_exit for WASI
Can't use `exit()` because it is too high level.
Have to unlock the thread list.
Signed-off-by: Harald Hoyer <harald@profian.com>
* fix: initialize struct pthread for the main thread
Signed-off-by: Harald Hoyer <harald@profian.com>
* fix: store the aligned stack minus `struct start_args`
Signed-off-by: Harald Hoyer <harald@profian.com>
Signed-off-by: Harald Hoyer <harald@profian.com>
Co-authored-by: Harald Hoyer <harald@profian.com>
* Add a check to command modules to ensure that they're only started once.
Wasm command modules should only be called once per instance, because
the programming model doesn't leave linear memory in a reusable state
when the program exits. As use cases arise for loading wasm modules in
environments that want to treat them like reactors, add a safety check
to ensure that command modules are used according to their
expectations.
* threads: implement `pthread_create`
As described in the [`wasi-threads`] proposal, this change implements
`pthread_create` using the new `wasi_thread_spawn(void *arg)` API. As
described there, `wasi-libc` exports the thread entry point with the
expected name, `wasi_thread_start`, and then unwraps the passed argument
`struct` to invoke the user function with the user argument `struct`.
[`wasi-threads`]: https://github.com/WebAssembly/wasi-threads/pull/5
Previously, the TID was only passed to the child thread entry point; the
parent thread was forced to wait until the child thread set the TID in
the pthread structure. With this change, the TID will be passed not only
to the child thread but also returned to the parent thread, so that
either side can make progress. The `i32.store` becomes an
`i32.atomic.store` to avoid concurrent writes.
Previously, "new-style commmands" considered every user-defined
export to be a potential command entrypoint, so wasi-libc and wasm-ld
cooperated to run the user's static constructors on each entrypoint.
This form of new-style command turned out not to be useful, and it
interferes with some use cases, so disable it.
This is done by making an explicit call to `__wasm_call_ctors`, which
tells wasm-ld that it shouldn't synthesize any calls to
`__wasm_call_ctors` on its own.
* Fixes for the THREAD_MODEL=posix build
* Fix expected symbols from previous commit
* Enable `lock` in `random.c` when threads are enabled
This uses the `_REENTRANT` definition to indicate when the `lock` should
be available.
* Disable `aio.h` when compiling for threads
In talking to @sunfishcode about `aio.h`, this functionality is not yet
a primary concern (it was already disabled in the default,
single-threaded mode). Additionally, this change adds expectation lines
for the new symbols/includes added and removed by `pthread.h`.
This change was reached by running:
```console
$ git diff --no-index expected/wasm32-wasi sysroot/share/wasm32-wasi > patch.diff
# replace "sysroot/share" with "expected" in `patch.diff`
$ git apply patch.diff --reject
# manually fix any rejections
```
* Specify the TLS model until LLVM 15 is released
The `-ftls-model` configuration can be removed once https://reviews.llvm.org/D130053 makes its way into an upstream release.
* Rename `__wasi_libc_pthread_self` to `__wasilibc_pthread_self`
The symbol is still undefined, though.
* Add different sets of expected output based on THREAD_MODEL
* Re-add trailing whitespace to `predefined-macros.txt`
@sbc100 wanted to retain the whitespace trailing after certain
predefined macro lines. This change restores that whitespace from
upstream and re-generates the POSIX version using the following command:
```console
$ git diff --no-index expected/wasm32-wasi/posix/predefined-macros.txt sysroot/share/wasm32-wasi/predefined-macros.txt | sed 's/sysroot\/share\/wasm32-wasi/expected\/wasm32-wasi\/posix/' | git apply
```
* Protect `preopens.c` against concurrent access
* Only build thread-capable wasi-libc on latest version of Clang
* Use `thrd_sleep` from MUSL instead of aliasing `nanosleep`
* Define `pthread_setcancelstate` in `THREAD_MODEL=posix` builds
There are other options here (e.g., always define the `pthread_*`
symbols with stubs) but until we discuss that this is an intermediate
working step.
* Define a Wasm global to store `pthread_self`
* Remove `g_needs_dynamic_alloc` global
* Document the state of pthread support
* review: de-duplicate symbols based on #314
* review: only define `__wasilibc_cwd_{un}lock` when needed
* review: add #ifdefs to `__pthread_setcancelstate`
* review: add additional #ifdefs to `pthread_self.c`
* review: put lock definition behind #ifdef _REENTRANT
* review: remove pthread_setcancelstate.c
* review: re-fix indentation
* review: alias __clock_nanosleep in bottom half
* review: remove extra line
Co-authored-by: Sam Clegg <sbc@chromium.org>
This change extracts the `weak*`-related parts of #303 as a separate PR.
Note that this is slightly strange in that it uses some top-half MUSL
headers in the bottom-half code, but discussion around this led me to
believe that the advantages of, e.g., `LOCK` made this worthwhile.
Beyond just changing uses of `weak` to `__weak__`, we also MUSL's `weak`
and `weak_alias` macros in a few more places.
* Delete several blocks of unused code.
Delete several pieces of code from libc-bottom-half/cloudlibc that aren't in
use on wasi-libc.
* Delete more of `_CLOCK_PROCESS_CPUTIME_ID` or `_CLOCK_THREAD_CPUTIME_ID`.
* Add a `getpagesize` function.
This adds a `getpagesize` function. This interface is deprecated in POSIX,
but it's sufficiently widely used and not problematic in practice.
* Use musl's `getpagesize`.
* Enable the `getpagesize` declaration in unistd.h.
* Remove support for `__original_main`.
This was used in old LLVM versions. Recent LLVM versions all emit either
`__main_void` or `__main_argv_argc`, so we can use those directly.
* Update the CI to use LLVM 14.0.0.
Previously, utimensat would leave the mtim and/or atim timestamps
uninitialized when the `MTIM_NOW` or `ATIM_NOW` were in use, because
that means the respective timestamps are not used.
However, clang now automatically adds `noundef` to the arguments in
functions like `__wasi_path_filestat_set_times`, and there are cases
where simplifycfg can see paths where the uninitialized values are
passed to those `noundef` arguments.
To fix this, change the utimens code to zero out the timestamps when
they aren't in use, to avoid passing uninitialized arguments.
Since the socket address of the accepted socket is unknown,
all bytes are set to zero and the length is truncated to the size
of the generic `struct sockaddr`.
Signed-off-by: Harald Hoyer <harald@profian.com>