cosmopolitan/libc/calls/directmap.c
Justine Tunney f684e348d4 Improve signals and memory protection
- Document sigaction()
- Simplify New Technology fork() code
- Testing and many bug fixes for mprotect()
- Distribute Intel Xed ILD in the amalgamation
- Turn Xed enums into defines to avoid DWARF bloat
- Improve polyfilling of SA_SIGINFO on BSDs and fix bugs
- setpgid(getpid(), getpid()) on Windows will ignore CTRL-C
- Work around issues relating to NT mappings being executable
- Permit automatic executable stack override via `ape_stack_pf`
2022-04-12 22:11:00 -07:00

52 lines
3.1 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/internal.h"
#include "libc/calls/strace.internal.h"
#include "libc/errno.h"
#include "libc/intrin/describeflags.internal.h"
#include "libc/nt/runtime.h"
#include "libc/runtime/directmap.internal.h"
#include "libc/runtime/memtrack.internal.h"
#include "libc/str/str.h"
/**
* Obtains memory mapping directly from system.
*
* The mmap() function needs to track memory mappings in order to
* support Windows NT and Address Sanitizer. That memory tracking can be
* bypassed by calling this function. However the caller is responsible
* for passing the magic memory handle on Windows NT to CloseHandle().
*/
noasan struct DirectMap sys_mmap(void *addr, size_t size, int prot, int flags,
int fd, int64_t off) {
/* asan runtime depends on this function */
struct DirectMap d;
if (!IsWindows() && !IsMetal()) {
d.addr = __sys_mmap(addr, size, prot, flags, fd, off, off);
d.maphandle = kNtInvalidHandleValue;
} else if (IsMetal()) {
d = sys_mmap_metal(addr, size, prot, flags, fd, off);
} else {
d = sys_mmap_nt(addr, size, prot, flags, fd, off);
}
STRACE("sys_mmap(%.12p%s, %'zu, %s, %s, %d, %'ld) → {%.12p, %p}% m", addr,
DescribeFrame((intptr_t)addr >> 16), size, DescribeProtFlags(prot),
DescribeMapFlags(flags), fd, off, d.addr, d.maphandle);
return d;
}