mirror of
https://github.com/apple/swift.git
synced 2025-12-14 20:36:38 +01:00
b2509d9306
We should always be using `<errno.h>`, not `<sys/errno.h>`. The former is part of the C standard. The latter is a non-standard header that happens to be present on some systems. rdar://123507361
532 lines
17 KiB
C++
532 lines
17 KiB
C++
//===--- CommandLine.cpp - OS-specific command line arguments -------------===//
|
|
//
|
|
// This source file is part of the Swift.org open source project
|
|
//
|
|
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
|
|
// Licensed under Apache License v2.0 with Runtime Library Exception
|
|
//
|
|
// See https://swift.org/LICENSE.txt for license information
|
|
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// OS-specific command line argument handling is defined here.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include <algorithm>
|
|
#include <cassert>
|
|
#include <climits>
|
|
#include <cstdarg>
|
|
#include <cstdint>
|
|
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <string>
|
|
|
|
#include <errno.h>
|
|
|
|
#include "swift/Runtime/Debug.h"
|
|
#include "swift/Runtime/Win32.h"
|
|
|
|
#include "swift/shims/GlobalObjects.h"
|
|
#include "swift/shims/RuntimeStubs.h"
|
|
#include "swift/shims/Visibility.h"
|
|
|
|
#if defined(_WIN32)
|
|
#define WIN32_LEAN_AND_MEAN
|
|
#include <Windows.h>
|
|
#include <shellapi.h>
|
|
#endif
|
|
|
|
// Backing storage for overrides of `Swift.CommandLine.arguments`.
|
|
static char **_swift_stdlib_ProcessOverrideUnsafeArgv = nullptr;
|
|
static int _swift_stdlib_ProcessOverrideUnsafeArgc = 0;
|
|
|
|
// This needs to findable by dlopen() for JIT purposes (see Immediate.cpp).
|
|
SWIFT_CC(swift) extern "C" SWIFT_ATTRIBUTE_FOR_EXPORTS
|
|
void _swift_stdlib_overrideUnsafeArgvArgc(char **argv, int argc) {
|
|
_swift_stdlib_ProcessOverrideUnsafeArgv = argv;
|
|
_swift_stdlib_ProcessOverrideUnsafeArgc = argc;
|
|
}
|
|
|
|
namespace swift {
|
|
/// A platform-specific implementation of @c _swift_stdlib_getUnsafeArgvArgc.
|
|
///
|
|
/// This function should return @c argc and @c argv cheaply (ideally in
|
|
/// constant time and without needing to allocate.) If it cannot do so,
|
|
/// it should return @c nullptr, at which point the caller can call
|
|
/// @c enumerateUnsafeArgv() in order to reconstruct @c argv locally.
|
|
///
|
|
/// The result of this function is @em not owned by the caller and should
|
|
/// persist for the lifetime of the process.
|
|
static char **getUnsafeArgvArgc(int *outArgLen);
|
|
|
|
/// A platform-specific function that enumerates the contents of @c argv
|
|
/// one argument at a time.
|
|
///
|
|
/// @a body is a function that takes two arguments:
|
|
///
|
|
/// - The first argument is the value of @c argc if it can be readily
|
|
/// computed, or @c -1 otherwise.
|
|
/// - The second argument is the element of @c argv being enumerated. The
|
|
/// caller makes a copy of this string. The implementation should not
|
|
/// enumerate the trailing @c nullptr required by the C standard.
|
|
///
|
|
/// Callers should call @c getUnsafeArgvArgc() before calling this function
|
|
/// in case a fast path is available. If that function is implemented on this
|
|
/// platform, then this function does not need to be implemented.
|
|
template <typename F>
|
|
static void enumerateUnsafeArgv(const F& body);
|
|
}
|
|
|
|
SWIFT_CC(swift) SWIFT_RUNTIME_STDLIB_INTERNAL
|
|
char **_swift_stdlib_getUnsafeArgvArgc(int *outArgLen) {
|
|
assert(outArgLen != nullptr);
|
|
|
|
// Check the override before doing any platform-specific work.
|
|
if (SWIFT_UNLIKELY(_swift_stdlib_ProcessOverrideUnsafeArgv)) {
|
|
*outArgLen = _swift_stdlib_ProcessOverrideUnsafeArgc;
|
|
return _swift_stdlib_ProcessOverrideUnsafeArgv;
|
|
}
|
|
|
|
// Try the platform-specific fast path that avoids heap (re)allocation. Not
|
|
// all platforms implement this function.
|
|
if (auto argv = swift::getUnsafeArgvArgc(outArgLen)) {
|
|
return argv;
|
|
}
|
|
|
|
// Take a slower path wherein we construct the argv array one element at a
|
|
// time. If the enumeration function can provide us with a hint for argc, we
|
|
// can avoid calling realloc() more than once.
|
|
int maxArgc = 0;
|
|
int argc = 0;
|
|
char **argv = nullptr;
|
|
swift::enumerateUnsafeArgv([&] (int maxArgcHint, const char *arg) {
|
|
if (argc >= maxArgc) {
|
|
if (maxArgcHint > maxArgc) {
|
|
// The platform was able to cheaply get argc, so use the
|
|
// provided value.
|
|
maxArgc = maxArgcHint;
|
|
} else {
|
|
// The platform could not tell us argc, so grow the argument array by
|
|
// small amounts. We assume here that the command line doesn't usually
|
|
// have many arguments, so a small/linear growth factor should be safe.
|
|
//
|
|
// If we ask for space for 15 arguments on the first allocation, then
|
|
// when we call realloc (asking for additional space for the trailing
|
|
// nullptr), we'll avoid wasting memory due to malloc()'s granularity.
|
|
maxArgc = (maxArgc == 0) ? 15 : (maxArgc + 16);
|
|
}
|
|
|
|
// Reallocate (or initially allocate) the argv buffer. Overallocate by
|
|
// one element to allow for a trailing nullptr.
|
|
//
|
|
// NOTE: It is intentional that we do not simply use std::vector here.
|
|
// STL collections may call operator new() which can be overridden by
|
|
// client code and that client code could call back into Swift.
|
|
size_t argvSize = sizeof(char *) * (maxArgc + 1);
|
|
argv = reinterpret_cast<char **>(realloc(argv, argvSize));
|
|
if (!argv) {
|
|
swift::fatalError(0,
|
|
"Fatal error: Could not allocate space for %d commandline "
|
|
" arguments: %d\n",
|
|
argc, errno);
|
|
}
|
|
}
|
|
|
|
argv[argc] = strdup(arg);
|
|
argc += 1;
|
|
});
|
|
|
|
if (argv) {
|
|
// Ensure the arguments array has a trailing nullptr, per the C standard.
|
|
argv[argc] = nullptr;
|
|
|
|
} else {
|
|
// We didn't get any arguments and never ended up allocating an array.
|
|
// Return an empty array (save for the trailing nullptr) instead.
|
|
static char *emptyArgv[] = { nullptr };
|
|
argc = 0;
|
|
argv = emptyArgv;
|
|
}
|
|
|
|
*outArgLen = argc;
|
|
return argv;
|
|
}
|
|
|
|
#if defined(__APPLE__)
|
|
// NOTE: forward declare this rather than including crt_externs.h as not all
|
|
// SDKs provide it
|
|
extern "C" char ***_NSGetArgv(void);
|
|
extern "C" int *_NSGetArgc(void);
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
*outArgLen = *_NSGetArgc();
|
|
return *_NSGetArgv();
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) { }
|
|
#elif defined(__linux__)
|
|
// On Linux, there is no easy way to get the argument vector pointer outside
|
|
// of the main() function. However, the ABI specifications dictate the layout
|
|
// of the process's initial stack, which looks something like:
|
|
//
|
|
// stack top ----> ┌────────────────────────┐
|
|
// │ Unspecified │
|
|
// ┊ ┊
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Information block │
|
|
// │ (argument strings, │
|
|
// │ environment strings, │
|
|
// │ auxiliary information) │
|
|
// ┊ ┊
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Unspecified │
|
|
// ┊ ┊
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ NULL │
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Auxiliary Vector │
|
|
// ┊ ┊
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ NULL │
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Environment Pointers │
|
|
// ┊ ┊
|
|
// environ ------> ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ NULL │
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Argument Pointers │
|
|
// ┊ ┊
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// │ Argument Count │
|
|
// ├┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┤
|
|
// ┊ ┊
|
|
//
|
|
// See https://gitlab.com/x86-psABIs/x86-64-ABI,
|
|
// https://gitlab.com/x86-psABIs/i386-ABI
|
|
//
|
|
// The upshot is that if we can get hold of `environ` before anything has
|
|
// had a chance to change it, we can find the `argv` array and also the
|
|
// argument count, `argc`, by walking back up the stack.
|
|
//
|
|
// (Note that Linux uses this same layout for all platforms, not just x86-based
|
|
// ones. It also has a fixed layout for the data at the top of the stack, but
|
|
// we don't need to take advantage of that here and can stick to things that
|
|
// are defined in the ABI specs.)
|
|
|
|
#include <unistd.h>
|
|
|
|
#define DEBUG_ARGVGRABBER 0
|
|
#if DEBUG_ARGVGRABBER
|
|
#define ARGVDEBUG(...) fprintf(stderr, __VA_ARGS__)
|
|
#else
|
|
#define ARGVDEBUG(...)
|
|
#endif
|
|
|
|
namespace {
|
|
|
|
struct ArgvGrabber {
|
|
char **argv;
|
|
int argc;
|
|
|
|
ArgvGrabber();
|
|
|
|
private:
|
|
struct stack {
|
|
void *base;
|
|
void *top;
|
|
|
|
stack() : base(nullptr), top(nullptr) {}
|
|
stack(void *b, void *t) : base(b), top(t) {}
|
|
};
|
|
|
|
stack findStack();
|
|
void findArgv(stack s);
|
|
};
|
|
|
|
// Find the stack by looking at /proc/self/maps
|
|
ArgvGrabber::stack ArgvGrabber::findStack(void) {
|
|
FILE *maps = fopen("/proc/self/maps", "r");
|
|
if (!maps) {
|
|
ARGVDEBUG("unable to open maps - %d\n", errno);
|
|
return stack();
|
|
}
|
|
|
|
char line[256];
|
|
void *base = NULL, *top = NULL;
|
|
bool found = false;
|
|
while (fgets(line, sizeof(line), maps)) {
|
|
// line is on the stack, so we know we're looking at the right
|
|
// region if line is between base and top.
|
|
//
|
|
// Note that we can't look for [stack], because Rosetta and qemu
|
|
// set up a separate stack for the emulated code.
|
|
//
|
|
// We also need to glom on extra VM ranges after the first one
|
|
// we find, because *sometimes* we end up with an extra range.
|
|
void *lo, *hi;
|
|
if (sscanf(line, "%p-%p", &lo, &hi) == 2) {
|
|
if ((void *)line >= lo && (void *)line < hi) {
|
|
base = lo;
|
|
top = hi;
|
|
found = true;
|
|
} else if (found && top == lo) {
|
|
top = hi;
|
|
}
|
|
}
|
|
}
|
|
|
|
fclose(maps);
|
|
|
|
if (!found) {
|
|
ARGVDEBUG("stack not found in maps\n");
|
|
return stack();
|
|
}
|
|
|
|
return stack(base, top);
|
|
}
|
|
|
|
#if DEBUG_ARGVGRABBER
|
|
void printMaps() {
|
|
FILE *maps = fopen("/proc/self/maps", "r");
|
|
if (!maps) {
|
|
fprintf(stderr, "unable to open maps - %d\n", errno);
|
|
return;
|
|
}
|
|
|
|
char line[256];
|
|
while (fgets(line, sizeof(line), maps)) {
|
|
fputs(line, stderr);
|
|
}
|
|
|
|
fclose(maps);
|
|
}
|
|
#endif
|
|
|
|
// Find argv by walking backwards from environ
|
|
void ArgvGrabber::findArgv(ArgvGrabber::stack stack) {
|
|
if (!stack.base) {
|
|
ARGVDEBUG("no stack\n");
|
|
return;
|
|
}
|
|
|
|
// Check that environ points to the stack
|
|
char **envp = environ;
|
|
if ((void *)envp < stack.base || (void *)envp >= stack.top) {
|
|
ARGVDEBUG("envp = %p, stack is from %p to %p\n",
|
|
envp, stack.base, stack.top);
|
|
#if DEBUG_ARGVGRABBER
|
|
printMaps();
|
|
#endif
|
|
return;
|
|
}
|
|
|
|
char **ptr = envp - 1;
|
|
|
|
// We're now pointing at the NULL that terminates argv. Keep going back
|
|
// while we're seeing pointers (values greater than envp).
|
|
while ((void *)(ptr - 1) > stack.base) {
|
|
--ptr;
|
|
|
|
// The first thing less than envp must be the argc value
|
|
if ((void *)*ptr < (void *)envp) {
|
|
argc = (int)(intptr_t)*ptr++;
|
|
argv = ptr;
|
|
return;
|
|
}
|
|
}
|
|
|
|
ARGVDEBUG("didn't find argc\n");
|
|
}
|
|
|
|
ArgvGrabber::ArgvGrabber() : argv(nullptr), argc(0) {
|
|
ARGVDEBUG("***GRABBING ARGV for %d***\n", getpid());
|
|
findArgv(findStack());
|
|
#if DEBUG_ARGVGRABBER
|
|
fprintf(stderr, "ARGV is at %p with count %d\n", argv, argc);
|
|
for (int i = 0; i < argc; ++i) {
|
|
fprintf(stderr, " argv[%d] = \"%s\"\n", i, argv[i]);
|
|
}
|
|
fprintf(stderr, "***ARGV GRABBED***\n");
|
|
#endif
|
|
}
|
|
|
|
ArgvGrabber argvGrabber;
|
|
|
|
} // namespace
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
*outArgLen = argvGrabber.argc;
|
|
return argvGrabber.argv;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) { }
|
|
#elif defined(__CYGWIN__)
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
return nullptr;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) {
|
|
FILE *cmdline = fopen("/proc/self/cmdline", "rb");
|
|
if (!cmdline) {
|
|
swift::fatalError(0,
|
|
"Fatal error: Unable to open interface to '/proc/self/cmdline': %d.\n",
|
|
errno);
|
|
}
|
|
|
|
char *arg = nullptr;
|
|
size_t size = 0;
|
|
while (getdelim(&arg, &size, '\0', cmdline) != -1) {
|
|
body(-1, arg);
|
|
}
|
|
if (arg) {
|
|
free(arg);
|
|
}
|
|
|
|
fclose(cmdline);
|
|
}
|
|
#elif defined(_WIN32)
|
|
#include <stdlib.h>
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
return nullptr;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) {
|
|
int argc = 0;
|
|
if (LPWSTR *wargv = CommandLineToArgvW(GetCommandLineW(), &argc)) {
|
|
std::for_each(wargv, wargv + argc, [=] (wchar_t *warg) {
|
|
if (char *arg = _swift_win32_copyUTF8FromWide(warg)) {
|
|
body(argc, arg);
|
|
free(arg);
|
|
} else {
|
|
// Note that GetLastError() and errno may not be so useful here,
|
|
// as in the error case we may have called free(), which might reset
|
|
// either or both of them.
|
|
swift::fatalError(0,
|
|
"Fatal error: Unable to convert argument '%ls' to "
|
|
"UTF-8: %lx, %d.\n",
|
|
warg, ::GetLastError(), errno);
|
|
}
|
|
});
|
|
|
|
LocalFree(wargv);
|
|
}
|
|
}
|
|
#elif defined(__FreeBSD__)
|
|
#include <errno.h>
|
|
#include <sys/param.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/types.h>
|
|
#include <unistd.h>
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
return nullptr;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) {
|
|
char *argPtr = nullptr; // or use ARG_MAX? 8192 is used in LLDB though..
|
|
int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_ARGS, getpid()};
|
|
size_t argPtrSize = 0;
|
|
for (int i = 0; i < 3 && !argPtr; ++i) { // give up after 3 tries
|
|
if (sysctl(mib, 4, nullptr, &argPtrSize, nullptr, 0) != -1) {
|
|
argPtr = static_cast<char *>(malloc(argPtrSize));
|
|
if (sysctl(mib, 4, argPtr, &argPtrSize, nullptr, 0) == -1) {
|
|
free(argPtr);
|
|
argPtr = nullptr;
|
|
if (errno != ENOMEM)
|
|
break;
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
if (!argPtr)
|
|
swift::fatalError(0,
|
|
"Fatal error: Could not retrieve commandline "
|
|
"arguments: sysctl: %s.\n",
|
|
strerror(errno));
|
|
|
|
char *curPtr = argPtr;
|
|
char *endPtr = argPtr + argPtrSize;
|
|
|
|
for (; curPtr < endPtr; curPtr += strlen(curPtr) + 1) {
|
|
body(-1, curPtr);
|
|
}
|
|
free(argPtr);
|
|
}
|
|
#elif defined(__wasi__)
|
|
#include <stdlib.h>
|
|
#include <wasi/api.h>
|
|
#include <wasi/libc.h>
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
__wasi_errno_t err;
|
|
|
|
size_t argv_buf_size = 0;
|
|
size_t argc = 0;
|
|
err = __wasi_args_sizes_get(&argc, &argv_buf_size);
|
|
if (err != __WASI_ERRNO_SUCCESS) {
|
|
swift::fatalError(0,
|
|
"Fatal error: Could not retrieve commandline "
|
|
"arguments: %d.\n", static_cast<int>(err));
|
|
return nullptr;
|
|
}
|
|
|
|
char *argv_buf = static_cast<char *>(malloc(argv_buf_size));
|
|
char **argv = static_cast<char **>(calloc(argc + 1, sizeof(char *)));
|
|
|
|
err = __wasi_args_get((uint8_t **)argv, (uint8_t *)argv_buf);
|
|
if (err != __WASI_ERRNO_SUCCESS) {
|
|
swift::fatalError(0,
|
|
"Fatal error: Could not retrieve commandline "
|
|
"arguments: %d.\n", static_cast<int>(err));
|
|
return nullptr;
|
|
}
|
|
|
|
*outArgLen = static_cast<int>(argc);
|
|
|
|
return argv;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) { }
|
|
#elif defined(__OpenBSD__)
|
|
#include <sys/types.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/exec.h>
|
|
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
int mib[2] = {CTL_VM, VM_PSSTRINGS};
|
|
struct _ps_strings _ps;
|
|
size_t len = sizeof(_ps);
|
|
|
|
if (sysctl(mib, 2, &_ps, &len, NULL, 0) == -1) {
|
|
return nullptr;
|
|
}
|
|
|
|
struct ps_strings *ps = static_cast<struct ps_strings *>(_ps.val);
|
|
*outArgLen = ps->ps_nargvstr;
|
|
return ps->ps_argvstr;
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) { }
|
|
#else // Add your favorite OS's command line arg grabber here.
|
|
static char **swift::getUnsafeArgvArgc(int *outArgLen) {
|
|
swift::fatalError(
|
|
0,
|
|
"Fatal error: Command line arguments not supported on this platform.\n");
|
|
}
|
|
|
|
template <typename F>
|
|
static void swift::enumerateUnsafeArgv(const F& body) { }
|
|
#endif
|