cosmopolitan/libc/calls/winexec.c
2024-08-04 12:52:25 -07:00

93 lines
3.9 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2023 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/struct/sigset.internal.h"
#include "libc/nt/errors.h"
#include "libc/nt/events.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/nt/struct/overlapped.h"
#include "libc/str/str.h"
#include "libc/str/tab.h"
#include "third_party/linenoise/linenoise.h"
#define Read32(s) (s[3] << 24 | s[2] << 16 | s[1] << 8 | s[0])
#define EXT(s) Read32(s "\0\0")
static inline bool IsGraph(wint_t c) {
return 0x21 <= c && c <= 0x7E;
}
static uint32_t GetFileExtension(const char16_t *s) {
uint32_t w;
size_t i, n;
n = s ? strlen16(s) : 0;
for (i = w = 0; n--;) {
wint_t c = s[n];
if (!IsGraph(c))
return 0;
if (c == '.')
break;
if (++i > 4)
return 0;
w <<= 8;
w |= kToLower[c];
}
return w;
}
// checks if file should be considered an executable on windows
textwindows int IsWindowsExecutable(int64_t handle, const char16_t *path) {
// fast path known file extensions
// shaves away 100ms of gnu make latency in cosmo monorepo
uint32_t ext;
if (!IsTiny() && (ext = GetFileExtension(path))) {
if (ext == EXT("c") || // c code
ext == EXT("cc") || // c++ code
ext == EXT("h") || // c/c++ header
ext == EXT("s") || // assembly code
ext == EXT("o")) { // object file
return false;
}
if (ext == EXT("com") || // mz executable
ext == EXT("exe") || // mz executable
ext == EXT("sh")) { // bourne shells
return true;
}
}
// read first two bytes of file
// access() and stat() aren't cancelation points
bool ok;
char buf[2];
uint32_t got;
BLOCK_SIGNALS;
struct NtOverlapped overlap = {.hEvent = CreateEvent(0, 0, 0, 0)};
ok = (ReadFile(handle, buf, 2, 0, &overlap) ||
GetLastError() == kNtErrorIoPending) &&
GetOverlappedResult(handle, &overlap, &got, true);
CloseHandle(overlap.hEvent);
ALLOW_SIGNALS;
// it's an executable if it starts with `MZ` or `#!`
return ok && got == 2 && //
((buf[0] == 'M' && buf[1] == 'Z') || //
(buf[0] == '#' && buf[1] == '!'));
}