blob: 6a87eb4b7b950e83a6a015c5ca992dfc1f572215 [file] [log] [blame]
/*
* Copyright 2006 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtc_base/flags.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "rtc_base/checks.h"
#if defined(WEBRTC_WIN)
// clang-format off
// clang formating would change include order.
#include <windows.h>
#include <shellapi.h> // must come after windows.h
// clang-format on
#include "rtc_base/string_utils.h" // For ToUtf8
#endif
namespace {
bool FlagEq(const char* arg, const char* flag) {
// Compare two flags for equality.
// 'arg' is the name of a flag passed via the command line and 'flag' is the
// name of a flag defined with the DEFINE_* macros.
// We compare the flags for equality, considering hyphens (-) and
// underscores (_) to be equivalent, so that --flag-name and --flag_name both
// match with --flag_name.
while (*arg != '\0' && (*arg == *flag || (*arg == '-' && *flag == '_'))) {
++arg;
++flag;
}
return *arg == '\0' && *flag == '\0';
}
} // namespace
namespace rtc {
// -----------------------------------------------------------------------------
// Implementation of Flag
Flag::Flag(const char* file,
const char* name,
const char* comment,
Type type,
void* variable,
FlagValue default__)
: file_(file),
name_(name),
comment_(comment),
type_(type),
variable_(reinterpret_cast<FlagValue*>(variable)),
default_(default__) {
FlagList::Register(this);
}
void Flag::SetToDefault() {
// Note that we cannot simply do '*variable_ = default_;' since
// flag variables are not really of type FlagValue and thus may
// be smaller! The FlagValue union is simply 'overlayed' on top
// of a flag variable for convenient access. Since union members
// are guarantee to be aligned at the beginning, this works.
switch (type_) {
case Flag::BOOL:
variable_->b = default_.b;
return;
case Flag::INT:
variable_->i = default_.i;
return;
case Flag::FLOAT:
variable_->f = default_.f;
return;
case Flag::STRING:
variable_->s = default_.s;
return;
}
FATAL() << "unreachable code";
}
static const char* Type2String(Flag::Type type) {
switch (type) {
case Flag::BOOL:
return "bool";
case Flag::INT:
return "int";
case Flag::FLOAT:
return "float";
case Flag::STRING:
return "string";
}
FATAL() << "unreachable code";
}
static void PrintFlagValue(Flag::Type type, FlagValue* p) {
switch (type) {
case Flag::BOOL:
printf("%s", (p->b ? "true" : "false"));
return;
case Flag::INT:
printf("%d", p->i);
return;
case Flag::FLOAT:
printf("%f", p->f);
return;
case Flag::STRING:
printf("%s", p->s);
return;
}
FATAL() << "unreachable code";
}
void Flag::Print(bool print_current_value) {
printf(" --%s (%s) type: %s default: ", name_, comment_,
Type2String(type_));
PrintFlagValue(type_, &default_);
if (print_current_value) {
printf(" current value: ");
PrintFlagValue(type_, variable_);
}
printf("\n");
}
// -----------------------------------------------------------------------------
// Implementation of FlagList
Flag* FlagList::list_ = nullptr;
FlagList::FlagList() {
list_ = nullptr;
}
void FlagList::Print(const char* file, bool print_current_value) {
// Since flag registration is likely by file (= C++ file),
// we don't need to sort by file and still get grouped output.
const char* current = nullptr;
for (Flag* f = list_; f != nullptr; f = f->next()) {
if (file == nullptr || file == f->file()) {
if (current != f->file()) {
printf("Flags from %s:\n", f->file());
current = f->file();
}
f->Print(print_current_value);
}
}
}
Flag* FlagList::Lookup(const char* name) {
Flag* f = list_;
while (f != nullptr && !FlagEq(name, f->name()))
f = f->next();
return f;
}
void FlagList::SplitArgument(const char* arg,
char* buffer,
int buffer_size,
const char** name,
const char** value,
bool* is_bool) {
*name = nullptr;
*value = nullptr;
*is_bool = false;
if (*arg == '-') {
// find the begin of the flag name
arg++; // remove 1st '-'
if (*arg == '-')
arg++; // remove 2nd '-'
if (arg[0] == 'n' && arg[1] == 'o' && Lookup(arg + 2)) {
arg += 2; // remove "no"
*is_bool = true;
}
*name = arg;
// find the end of the flag name
while (*arg != '\0' && *arg != '=')
arg++;
// get the value if any
if (*arg == '=') {
// make a copy so we can NUL-terminate flag name
int n = static_cast<int>(arg - *name);
RTC_CHECK_LT(n, buffer_size);
memcpy(buffer, *name, n * sizeof(char));
buffer[n] = '\0';
*name = buffer;
// get the value
*value = arg + 1;
}
}
}
int FlagList::SetFlagsFromCommandLine(int* argc,
const char** argv,
bool remove_flags) {
// parse arguments
for (int i = 1; i < *argc; /* see below */) {
int j = i; // j > 0
const char* arg = argv[i++];
// split arg into flag components
char buffer[1024];
const char* name;
const char* value;
bool is_bool;
SplitArgument(arg, buffer, sizeof buffer, &name, &value, &is_bool);
if (name != nullptr) {
// lookup the flag
Flag* flag = Lookup(name);
if (flag == nullptr) {
fprintf(stderr, "Error: unrecognized flag %s\n", arg);
return j;
}
// if we still need a flag value, use the next argument if available
if (flag->type() != Flag::BOOL && value == nullptr) {
if (i < *argc) {
value = argv[i++];
} else {
fprintf(stderr, "Error: missing value for flag %s of type %s\n", arg,
Type2String(flag->type()));
return j;
}
}
// set the flag
char empty[] = {'\0'};
char* endp = empty;
switch (flag->type()) {
case Flag::BOOL:
*flag->bool_variable() = !is_bool;
break;
case Flag::INT:
*flag->int_variable() = strtol(value, &endp, 10);
break;
case Flag::FLOAT:
*flag->float_variable() = strtod(value, &endp);
break;
case Flag::STRING:
*flag->string_variable() = value;
break;
}
// handle errors
if ((flag->type() == Flag::BOOL && value != nullptr) ||
(flag->type() != Flag::BOOL && is_bool) || *endp != '\0') {
fprintf(stderr, "Error: illegal value for flag %s of type %s\n", arg,
Type2String(flag->type()));
return j;
}
// remove the flag & value from the command
if (remove_flags)
while (j < i)
argv[j++] = nullptr;
}
}
// shrink the argument list
if (remove_flags) {
int j = 1;
for (int i = 1; i < *argc; i++) {
if (argv[i] != nullptr)
argv[j++] = argv[i];
}
*argc = j;
}
// parsed all flags successfully
return 0;
}
void FlagList::Register(Flag* flag) {
RTC_DCHECK(flag);
RTC_DCHECK_GT(strlen(flag->name()), 0);
// NOTE: Don't call Lookup() within Register because it accesses the name_
// of other flags in list_, and if the flags are coming from two different
// compilation units, the initialization order between them is undefined, and
// this will trigger an asan initialization-order-fiasco error.
flag->next_ = list_;
list_ = flag;
}
#if defined(WEBRTC_WIN)
WindowsCommandLineArguments::WindowsCommandLineArguments() {
// start by getting the command line.
LPTSTR command_line = ::GetCommandLine();
// now, convert it to a list of wide char strings.
LPWSTR* wide_argv = ::CommandLineToArgvW(command_line, &argc_);
// now allocate an array big enough to hold that many string pointers.
argv_ = new char*[argc_];
// iterate over the returned wide strings;
for (int i = 0; i < argc_; ++i) {
std::string s = rtc::ToUtf8(wide_argv[i], wcslen(wide_argv[i]));
char* buffer = new char[s.length() + 1];
rtc::strcpyn(buffer, s.length() + 1, s.c_str());
// make sure the argv array has the right string at this point.
argv_[i] = buffer;
}
LocalFree(wide_argv);
}
WindowsCommandLineArguments::~WindowsCommandLineArguments() {
// need to free each string in the array, and then the array.
for (int i = 0; i < argc_; i++) {
delete[] argv_[i];
}
delete[] argv_;
}
#endif // WEBRTC_WIN
} // namespace rtc