skia2/tools/SkFlags.h
skia.committer@gmail.com 075b089b1b Sanitizing source files in Skia_Periodic_House_Keeping
git-svn-id: http://skia.googlecode.com/svn/trunk@7976 2bbb7eff-a529-9590-31e7-b0007b416f81
2013-03-05 07:09:08 +00:00

346 lines
11 KiB
C++

/*
* Copyright 2013 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SK_FLAGS_H
#define SK_FLAGS_H
#include "SkString.h"
#include "SkTDArray.h"
/**
* Including this file (and compiling SkFlags.cpp) provides command line
* parsing. In order to use it, use the following macros in global
* namespace:
*
* DEFINE_bool(name, defaultValue, helpString);
* DEFINE_string(name, defaultValue, helpString);
* DEFINE_int32(name, defaultValue, helpString);
* DEFINE_double(name, defaultValue, helpString);
*
* Then, in main, call SkFlags::SetUsage() to describe usage and call
* SkFlags::ParseCommandLine() to parse the flags. Henceforth, each flag can
* be referenced using
*
* FLAGS_name
*
* For example, the line
*
* DEFINE_bool(boolean, false, "The variable boolean does such and such");
*
* will create the following variable:
*
* bool FLAGS_boolean;
*
* which will initially be set to false, and can be set to true by using the
* flag "--boolean" on the commandline. "--noboolean" will set FLAGS_boolean
* to false. (Single dashes are also permitted for this and other flags.) The
* helpString will be printed if the help flag (-h or -help) is used.
*
* Similarly, the line
*
* DEFINE_int32(integer, .., ..);
*
* will create
*
* int32_t FLAGS_integer;
*
* and
*
* DEFINE_double(real, .., ..);
*
* will create
*
* double FLAGS_real;
*
* These flags can be set by specifying, for example, "--integer 7" and
* "--real 3.14" on the command line.
*
* Unlike the others, the line
*
* DEFINE_string(args, .., ..);
*
* creates an array:
*
* SkTDArray<const char*> FLAGS_args;
*
* If the default value is the empty string, FLAGS_args will default to a size
* of zero. Otherwise it will default to a size of 1 with the default string
* as its value. All strings that follow the flag on the command line (until
* a string that begins with '-') will be entries in the array.
*
* Any flag can be referenced from another file after using the following:
*
* DECLARE_x(name);
*
* (where 'x' is the type specified in the DEFINE).
*
* Inspired by gflags (https://code.google.com/p/gflags/). Is not quite as
* robust as gflags, but suits our purposes. For example, allows creating
* a flag -h or -help which will never be used, since SkFlags handles it.
* SkFlags will also allow creating --flag and --noflag. Uses the same input
* format as gflags and creates similarly named variables (i.e. FLAGS_name).
* Strings are handled differently (resulting variable will be an array of
* strings) so that a flag can be followed by multiple parameters.
*/
class SkFlagInfo;
class SkFlags {
public:
/**
* Call to set the help message to be displayed. Should be called before
* ParseCommandLine.
*/
static void SetUsage(const char* usage);
/**
* Call at the beginning of main to parse flags created by DEFINE_x, above.
* Must only be called once.
*/
static void ParseCommandLine(int argc, char** argv);
private:
static SkFlagInfo* gHead;
static SkString gUsage;
// For access to gHead.
friend class SkFlagInfo;
};
#define TO_STRING2(s) #s
#define TO_STRING(s) TO_STRING2(s)
#define DEFINE_bool(name, defaultValue, helpString) \
bool FLAGS_##name; \
static bool unused_##name = SkFlagInfo::CreateBoolFlag(TO_STRING(name), \
&FLAGS_##name, \
defaultValue, \
helpString)
#define DECLARE_bool(name) extern bool FLAGS_##name;
#define DEFINE_string(name, defaultValue, helpString) \
SkTDArray<const char*> FLAGS_##name; \
static bool unused_##name = SkFlagInfo::CreateStringFlag(TO_STRING(name), \
&FLAGS_##name, \
defaultValue, \
helpString)
#define DECLARE_string(name) extern SkTDArray<const char*> FLAGS_##name;
#define DEFINE_int32(name, defaultValue, helpString) \
int32_t FLAGS_##name; \
static bool unused_##name = SkFlagInfo::CreateIntFlag(TO_STRING(name), \
&FLAGS_##name, \
defaultValue, \
helpString)
#define DECLARE_int32(name) extern int32_t FLAGS_##name;
#define DEFINE_double(name, defaultValue, helpString) \
double FLAGS_##name; \
static bool unused_##name = SkFlagInfo::CreateDoubleFlag(TO_STRING(name), \
&FLAGS_##name, \
defaultValue, \
helpString)
#define DECLARE_double(name) extern double FLAGS_##name;
class SkFlagInfo {
public:
enum FlagTypes {
kBool_FlagType,
kString_FlagType,
kInt_FlagType,
kDouble_FlagType,
};
// Create flags of the desired type, and append to the list.
static bool CreateBoolFlag(const char* name, bool* pBool,
bool defaultValue, const char* helpString) {
SkFlagInfo* info = SkNEW_ARGS(SkFlagInfo, (name, kBool_FlagType, helpString));
info->fBoolValue = pBool;
*info->fBoolValue = info->fDefaultBool = defaultValue;
return true;
}
static bool CreateStringFlag(const char* name, SkTDArray<const char*>* pStrings,
const char* defaultValue, const char* helpString) {
SkFlagInfo* info = SkNEW_ARGS(SkFlagInfo, (name, kString_FlagType, helpString));
info->fDefaultString.set(defaultValue);
info->fStrings = pStrings;
info->fStrings->reset();
// If default is "", leave the array empty.
if (info->fDefaultString.size() > 0) {
info->fStrings->append(1, &defaultValue);
}
return true;
}
static bool CreateIntFlag(const char* name, int32_t* pInt,
int32_t defaultValue, const char* helpString) {
SkFlagInfo* info = SkNEW_ARGS(SkFlagInfo, (name, kInt_FlagType, helpString));
info->fIntValue = pInt;
*info->fIntValue = info->fDefaultInt = defaultValue;
return true;
}
static bool CreateDoubleFlag(const char* name, double* pDouble,
double defaultValue, const char* helpString) {
SkFlagInfo* info = SkNEW_ARGS(SkFlagInfo, (name, kDouble_FlagType, helpString));
info->fDoubleValue = pDouble;
*info->fDoubleValue = info->fDefaultDouble = defaultValue;
return true;
}
/**
* Returns true if the string matches this flag. For a bool, also sets the
* value, since a bool is specified as true or false by --name or --noname.
*/
bool match(const char* string) {
if (SkStrStartsWith(string, '-')) {
string++;
// Allow one or two dashes
if (SkStrStartsWith(string, '-')) {
string++;
}
if (kBool_FlagType == fFlagType) {
// In this case, go ahead and set the value.
if (fName.equals(string)) {
*fBoolValue = true;
return true;
}
SkString noname(fName);
noname.prepend("no");
if (noname.equals(string)) {
*fBoolValue = false;
return true;
}
return false;
}
return fName.equals(string);
} else {
// Has no dash
return false;
}
return false;
}
FlagTypes getFlagType() const { return fFlagType; }
void resetStrings() {
if (kString_FlagType == fFlagType) {
fStrings->reset();
} else {
SkASSERT(!"Can only call resetStrings on kString_FlagType");
}
}
void append(const char* string) {
if (kString_FlagType == fFlagType) {
fStrings->append(1, &string);
} else {
SkASSERT(!"Can only append to kString_FlagType");
}
}
void setInt(int32_t value) {
if (kInt_FlagType == fFlagType) {
*fIntValue = value;
} else {
SkASSERT(!"Can only call setInt on kInt_FlagType");
}
}
void setDouble(double value) {
if (kDouble_FlagType == fFlagType) {
*fDoubleValue = value;
} else {
SkASSERT(!"Can only call setDouble on kDouble_FlagType");
}
}
SkFlagInfo* next() { return fNext; }
const SkString& name() const { return fName; }
const SkString& help() const { return fHelpString; }
SkString defaultValue() const {
SkString result;
switch (fFlagType) {
case SkFlagInfo::kBool_FlagType:
result.printf("%s", fDefaultBool ? "true" : "false");
break;
case SkFlagInfo::kString_FlagType:
return fDefaultString;
case SkFlagInfo::kInt_FlagType:
result.printf("%i", fDefaultInt);
break;
case SkFlagInfo::kDouble_FlagType:
result.printf("%2.2f", fDefaultDouble);
break;
default:
SkASSERT(!"Invalid flag type");
}
return result;
}
SkString typeAsString() const {
switch (fFlagType) {
case SkFlagInfo::kBool_FlagType:
return SkString("bool");
case SkFlagInfo::kString_FlagType:
return SkString("string");
case SkFlagInfo::kInt_FlagType:
return SkString("int");
case SkFlagInfo::kDouble_FlagType:
return SkString("double");
default:
SkASSERT(!"Invalid flag type");
return SkString();
}
}
private:
SkFlagInfo(const char* name, FlagTypes type, const char* helpString)
: fName(name)
, fFlagType(type)
, fHelpString(helpString)
, fBoolValue(NULL)
, fDefaultBool(false)
, fIntValue(NULL)
, fDefaultInt(0)
, fDoubleValue(NULL)
, fDefaultDouble(0)
, fStrings(NULL) {
fNext = SkFlags::gHead;
SkFlags::gHead = this;
}
// Name of the flag, without initial dashes
SkString fName;
FlagTypes fFlagType;
SkString fHelpString;
bool* fBoolValue;
bool fDefaultBool;
int32_t* fIntValue;
int32_t fDefaultInt;
double* fDoubleValue;
double fDefaultDouble;
SkTDArray<const char*>* fStrings;
// Both for the help string and in case fStrings is empty.
SkString fDefaultString;
// In order to keep a linked list.
SkFlagInfo* fNext;
};
#endif // SK_FLAGS_H