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d1d4388201
It hasn't been helpful enough to be justify the maintenance burden. What actually does help is mprotect(), kprintf(), --ftrace and --strace which can always be counted upon to work correctly. We aren't losing much with this change. Support for ASAN on AARCH64 was never implemented. Applying ASAN to the core libc runtimes was disabled many months ago. If there is some way to have an ASAN runtime for user programs that is less invasive we can potentially consider reintroducing support. But now is premature.
68 lines
3.8 KiB
C
68 lines
3.8 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2021 Justine Alexandra Roberts Tunney │
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│ │
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│ Permission to use, copy, modify, and/or distribute this software for │
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│ any purpose with or without fee is hereby granted, provided that the │
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│ above copyright notice and this permission notice appear in all copies. │
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│ │
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│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
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│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
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│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
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│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
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│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
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│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
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│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
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│ PERFORMANCE OF THIS SOFTWARE. │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/calls/syscall-nt.internal.h"
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#include "libc/calls/syscall-sysv.internal.h"
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#include "libc/dce.h"
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#include "libc/intrin/describeflags.internal.h"
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#include "libc/intrin/strace.internal.h"
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#include "libc/intrin/weaken.h"
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#include "libc/runtime/runtime.h"
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#include "libc/runtime/zipos.internal.h"
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#include "libc/stdio/sysparam.h"
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#include "libc/sysv/errfuns.h"
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/**
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* Reads symbolic link.
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*
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* This does *not* nul-terminate the buffer.
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*
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* @param dirfd is normally AT_FDCWD but if it's an open directory and
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* file is a relative path, then file is opened relative to dirfd
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* @param path must be a symbolic link pathname
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* @param buf will receive symbolic link contents, and won't be modified
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* unless the function succeeds (with the exception of no-malloc nt)
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* and this buffer will *not* be nul-terminated
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* @return number of bytes written to buf, or -1 w/ errno; if the
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* return is equal to bufsiz then truncation may have occurred
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* @raise EINVAL if path isn't a symbolic link
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* @raise ENOENT if `path` didn't exist
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* @raise ENOTDIR if parent component existed that's not a directory
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* @raise ENOTDIR if base component ends with slash and is not a dir
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* @raise ENAMETOOLONG if symlink-resolved `path` length exceeds `PATH_MAX`
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* @raise ENAMETOOLONG if component in `path` exists longer than `NAME_MAX`
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* @raise EBADF on relative `path` when `dirfd` isn't open or `AT_FDCWD`
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* @raise ELOOP if a loop was detected resolving parent components
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* @asyncsignalsafe
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*/
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ssize_t readlinkat(int dirfd, const char *path, char *buf, size_t bufsiz) {
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ssize_t bytes;
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if ((bufsiz && !buf)) {
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bytes = efault();
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} else if (_weaken(__zipos_notat) &&
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(bytes = __zipos_notat(dirfd, path)) == -1) {
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STRACE("TODO: zipos support for readlinkat");
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} else if (!IsWindows()) {
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bytes = sys_readlinkat(dirfd, path, buf, bufsiz);
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} else {
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bytes = sys_readlinkat_nt(dirfd, path, buf, bufsiz);
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}
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STRACE("readlinkat(%s, %#s, [%#.*s]) → %d% m", DescribeDirfd(dirfd), path,
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(int)MAX(0, bytes), buf, bytes);
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return bytes;
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}
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