• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2013 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef SK_COMMAND_LINE_FLAGS_H
9 #define SK_COMMAND_LINE_FLAGS_H
10 
11 #include "../private/SkTArray.h"
12 #include "../private/SkTDArray.h"
13 #include "SkString.h"
14 
15 /**
16  *  Including this file (and compiling SkCommandLineFlags.cpp) provides command line
17  *  parsing. In order to use it, use the following macros in global
18  *  namespace:
19  *
20  *  DEFINE_bool(name, defaultValue, helpString);
21  *  DEFINE_string(name, defaultValue, helpString);
22  *  DEFINE_int32(name, defaultValue, helpString);
23  *  DEFINE_double(name, defaultValue, helpString);
24  *
25  *  Then, in main, call SkCommandLineFlags::SetUsage() to describe usage and call
26  *  SkCommandLineFlags::Parse() to parse the flags. Henceforth, each flag can
27  *  be referenced using
28  *
29  *  FLAGS_name
30  *
31  *  For example, the line
32  *
33  *  DEFINE_bool(boolean, false, "The variable boolean does such and such");
34  *
35  *  will create the following variable:
36  *
37  *  bool FLAGS_boolean;
38  *
39  *  which will initially be set to false, and can be set to true by using the
40  *  flag "--boolean" on the commandline. "--noboolean" will set FLAGS_boolean
41  *  to false. FLAGS_boolean can also be set using "--boolean=true" or
42  *  "--boolean true" (where "true" can be replaced by "false", "TRUE", "FALSE",
43  *  "1" or "0").
44  *
45  *  The helpString will be printed if the help flag (-h or -help) is used.
46  *
47  *  Similarly, the line
48  *
49  *  DEFINE_int32(integer, .., ..);
50  *
51  *  will create
52  *
53  *  int32_t FLAGS_integer;
54  *
55  *  and
56  *
57  *  DEFINE_double(real, .., ..);
58  *
59  *  will create
60  *
61  *  double FLAGS_real;
62  *
63  *  and
64  *
65  *  DEFINE_uint32(unsigned, ...);
66  *
67  *  will create
68  *
69  *  uint32_t FLAGS_unsigned;
70  *
71  *  These flags can be set by specifying, for example, "--integer 7" and
72  *  "--real 3.14" on the command line. Unsigned integers are parsed from the
73  *  command line using strtoul() so will detect the base (0 for octal, and
74  *  0x or 0X for hex, otherwise assumes decimal).
75  *
76  *  Unlike the others, the line
77  *
78  *  DEFINE_string(args, .., ..);
79  *
80  *  creates an array:
81  *
82  *  SkCommandLineFlags::StringArray FLAGS_args;
83  *
84  *  If the default value is the empty string, FLAGS_args will default to a size
85  *  of zero. Otherwise it will default to a size of 1 with the default string
86  *  as its value. All strings that follow the flag on the command line (until
87  *  a string that begins with '-') will be entries in the array.
88  *
89  *  DEFINE_extended_string(args, .., .., extendedHelpString);
90  *
91  *  creates a similar string array flag as DEFINE_string. The flag will have extended help text
92  *  (extendedHelpString) that can the user can see with '--help <args>' flag.
93  *
94  *  Any flag can be referenced from another file after using the following:
95  *
96  *  DECLARE_x(name);
97  *
98  *  (where 'x' is the type specified in the DEFINE).
99  *
100  *  Inspired by gflags (https://code.google.com/p/gflags/). Is not quite as
101  *  robust as gflags, but suits our purposes. For example, allows creating
102  *  a flag -h or -help which will never be used, since SkCommandLineFlags handles it.
103  *  SkCommandLineFlags will also allow creating --flag and --noflag. Uses the same input
104  *  format as gflags and creates similarly named variables (i.e. FLAGS_name).
105  *  Strings are handled differently (resulting variable will be an array of
106  *  strings) so that a flag can be followed by multiple parameters.
107  */
108 
109 class SkFlagInfo;
110 
111 class SkCommandLineFlags {
112 
113 public:
114     /**
115      *  Call to set the help message to be displayed. Should be called before
116      *  Parse.
117      */
118     static void SetUsage(const char* usage);
119 
120     /**
121      *  Call this to display the help message. Should be called after SetUsage.
122      */
123     static void PrintUsage();
124 
125     /**
126      *  Call at the beginning of main to parse flags created by DEFINE_x, above.
127      *  Must only be called once.
128      */
129     static void Parse(int argc, const char* const * argv);
130 
131     /**
132      *  Custom class for holding the arguments for a string flag.
133      *  Publicly only has accessors so the strings cannot be modified.
134      */
135     class StringArray {
136     public:
StringArray()137         StringArray() { }
StringArray(const SkTArray<SkString> & strings)138         explicit StringArray(const SkTArray<SkString>& strings)
139             : fStrings(strings) {
140         }
141         const char* operator[](int i) const {
142             SkASSERT(i >= 0 && i < fStrings.count());
143             return fStrings[i].c_str();
144         }
145 
count()146         int count() const {
147             return fStrings.count();
148         }
149 
isEmpty()150         bool isEmpty() const { return this->count() == 0; }
151 
152         /**
153          * Returns true iff string is equal to one of the strings in this array.
154          */
contains(const char * string)155         bool contains(const char* string) const {
156             for (int i = 0; i < fStrings.count(); i++) {
157                 if (fStrings[i].equals(string)) {
158                     return true;
159                 }
160             }
161             return false;
162         }
163 
set(int i,const char * str)164         void set(int i, const char* str) {
165             if (i >= fStrings.count()) {
166                 this->append(str);
167                 return;
168             }
169             fStrings[i].set(str);
170         }
171 
begin()172         const SkString* begin() const { return fStrings.begin(); }
end()173         const SkString*   end() const { return fStrings.end(); }
174 
175     private:
reset()176         void reset() { fStrings.reset(); }
177 
append(const char * string)178         void append(const char* string) {
179             fStrings.push_back().set(string);
180         }
181 
append(const char * string,size_t length)182         void append(const char* string, size_t length) {
183             fStrings.push_back().set(string, length);
184         }
185 
186         SkTArray<SkString> fStrings;
187 
188         friend class SkFlagInfo;
189     };
190 
191     /* Takes a list of the form [~][^]match[$]
192      ~ causes a matching test to always be skipped
193      ^ requires the start of the test to match
194      $ requires the end of the test to match
195      ^ and $ requires an exact match
196      If a test does not match any list entry, it is skipped unless some list entry starts with ~
197     */
198     static bool ShouldSkip(const SkTDArray<const char*>& strings, const char* name);
199     static bool ShouldSkip(const StringArray& strings, const char* name);
200 
201 private:
202     static SkFlagInfo* gHead;
203     static SkString    gUsage;
204 
205     // For access to gHead.
206     friend class SkFlagInfo;
207 };
208 
209 #define TO_STRING2(s) #s
210 #define TO_STRING(s) TO_STRING2(s)
211 
212 #define DEFINE_bool(name, defaultValue, helpString)                         \
213 bool FLAGS_##name;                                                          \
214 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateBoolFlag(TO_STRING(name),     \
215                                                                  nullptr,                \
216                                                                  &FLAGS_##name,       \
217                                                                  defaultValue,        \
218                                                                  helpString)
219 
220 // bool 2 allows specifying a short name. No check is done to ensure that shortName
221 // is actually shorter than name.
222 #define DEFINE_bool2(name, shortName, defaultValue, helpString)             \
223 bool FLAGS_##name;                                                          \
224 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateBoolFlag(TO_STRING(name),     \
225                                                                  TO_STRING(shortName),\
226                                                                  &FLAGS_##name,       \
227                                                                  defaultValue,        \
228                                                                  helpString)
229 
230 #define DECLARE_bool(name) extern bool FLAGS_##name;
231 
232 #define DEFINE_string(name, defaultValue, helpString)                       \
233 SkCommandLineFlags::StringArray FLAGS_##name;                               \
234 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateStringFlag(TO_STRING(name),   \
235                                                                    nullptr,              \
236                                                                    &FLAGS_##name,     \
237                                                                    defaultValue,      \
238                                                                    helpString, nullptr)
239 #define DEFINE_extended_string(name, defaultValue, helpString, extendedHelpString) \
240 SkCommandLineFlags::StringArray FLAGS_##name;                                      \
241 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateStringFlag(TO_STRING(name),   \
242                                                                    nullptr, \
243                                                                    &FLAGS_##name, \
244                                                                    defaultValue, \
245                                                                    helpString, \
246                                                                    extendedHelpString)
247 
248 // string2 allows specifying a short name. There is an assert that shortName
249 // is only 1 character.
250 #define DEFINE_string2(name, shortName, defaultValue, helpString)               \
251 SkCommandLineFlags::StringArray FLAGS_##name;                                   \
252 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateStringFlag(TO_STRING(name),       \
253                                                                    TO_STRING(shortName),  \
254                                                                    &FLAGS_##name,         \
255                                                                    defaultValue,          \
256                                                                    helpString, nullptr)
257 
258 #define DECLARE_string(name) extern SkCommandLineFlags::StringArray FLAGS_##name;
259 
260 
261 
262 
263 #define DEFINE_int32(name, defaultValue, helpString)                        \
264 int32_t FLAGS_##name;                                                       \
265 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateIntFlag(TO_STRING(name),      \
266                                                                 &FLAGS_##name,        \
267                                                                 defaultValue,         \
268                                                                 helpString)
269 
270 #define DEFINE_int32_2(name, shortName, defaultValue, helpString)                     \
271 int32_t FLAGS_##name;                                                                 \
272 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateIntFlag(TO_STRING(name),      \
273                                                                 TO_STRING(shortName), \
274                                                                 &FLAGS_##name,        \
275                                                                 defaultValue,         \
276                                                                 helpString)
277 
278 #define DECLARE_int32(name) extern int32_t FLAGS_##name;
279 
280 
281 #define DEFINE_uint32(name, defaultValue, helpString)                                 \
282 uint32_t FLAGS_##name;                                                                \
283 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateUintFlag(TO_STRING(name),     \
284                                                                  &FLAGS_##name,       \
285                                                                  defaultValue,        \
286                                                                  helpString)
287 
288 #define DEFINE_uint32_2(name, shortName, defaultValue, helpString)                    \
289 uint32_t FLAGS_##name;                                                                \
290 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateUintFlag(TO_STRING(name),     \
291                                                                  TO_STRING(shortName),\
292                                                                  &FLAGS_##name,       \
293                                                                  defaultValue,        \
294                                                                  helpString)
295 
296 #define DECLARE_uint32(name) extern uint32_t FLAGS_##name;
297 
298 
299 #define DEFINE_double(name, defaultValue, helpString)                       \
300 double FLAGS_##name;                                                        \
301 SK_UNUSED static bool unused_##name = SkFlagInfo::CreateDoubleFlag(TO_STRING(name),   \
302                                                                    &FLAGS_##name,     \
303                                                                    defaultValue,      \
304                                                                    helpString)
305 
306 #define DECLARE_double(name) extern double FLAGS_##name;
307 
308 class SkFlagInfo {
309 
310 public:
311     enum FlagTypes {
312         kBool_FlagType,
313         kString_FlagType,
314         kInt_FlagType,
315         kUint_FlagType,
316         kDouble_FlagType,
317     };
318 
319     /**
320      *  Each Create<Type>Flag function creates an SkFlagInfo of the specified type. The SkFlagInfo
321      *  object is appended to a list, which is deleted when SkCommandLineFlags::Parse is called.
322      *  Therefore, each call should be made before the call to ::Parse. They are not intended
323      *  to be called directly. Instead, use the macros described above.
324      *  @param name Long version (at least 2 characters) of the name of the flag. This name can
325      *      be referenced on the command line as "--name" to set the value of this flag.
326      *  @param shortName Short version (one character) of the name of the flag. This name can
327      *      be referenced on the command line as "-shortName" to set the value of this flag.
328      *  @param p<Type> Pointer to a global variable which holds the value set by SkCommandLineFlags.
329      *  @param defaultValue The default value of this flag. The variable pointed to by p<Type> will
330      *      be set to this value initially. This is also displayed as part of the help output.
331      *  @param helpString Explanation of what this flag changes in the program.
332      */
CreateBoolFlag(const char * name,const char * shortName,bool * pBool,bool defaultValue,const char * helpString)333     static bool CreateBoolFlag(const char* name, const char* shortName, bool* pBool,
334                                bool defaultValue, const char* helpString) {
335         SkFlagInfo* info = new SkFlagInfo(name, shortName, kBool_FlagType, helpString, nullptr);
336         info->fBoolValue = pBool;
337         *info->fBoolValue = info->fDefaultBool = defaultValue;
338         return true;
339     }
340 
341     /**
342      *  See comments for CreateBoolFlag.
343      *  @param pStrings Unlike the others, this is a pointer to an array of values.
344      *  @param defaultValue Thise default will be parsed so that strings separated by spaces
345      *      will be added to pStrings.
346      */
347     static bool CreateStringFlag(const char* name, const char* shortName,
348                                  SkCommandLineFlags::StringArray* pStrings,
349                                  const char* defaultValue, const char* helpString,
350                                  const char* extendedHelpString);
351 
352     /**
353      *  See comments for CreateBoolFlag.
354      */
CreateIntFlag(const char * name,int32_t * pInt,int32_t defaultValue,const char * helpString)355     static bool CreateIntFlag(const char* name, int32_t* pInt,
356                               int32_t defaultValue, const char* helpString) {
357         SkFlagInfo* info = new SkFlagInfo(name, nullptr, kInt_FlagType, helpString, nullptr);
358         info->fIntValue = pInt;
359         *info->fIntValue = info->fDefaultInt = defaultValue;
360         return true;
361     }
362 
CreateIntFlag(const char * name,const char * shortName,int32_t * pInt,int32_t defaultValue,const char * helpString)363     static bool CreateIntFlag(const char* name, const char* shortName, int32_t* pInt,
364                               int32_t defaultValue, const char* helpString) {
365         SkFlagInfo* info = new SkFlagInfo(name, shortName, kInt_FlagType, helpString, nullptr);
366         info->fIntValue = pInt;
367         *info->fIntValue = info->fDefaultInt = defaultValue;
368         return true;
369     }
370 
371     /**
372      *  See comments for CreateBoolFlag.
373      */
CreateUintFlag(const char * name,uint32_t * pUint,uint32_t defaultValue,const char * helpString)374     static bool CreateUintFlag(const char* name, uint32_t* pUint,
375                                uint32_t defaultValue, const char* helpString) {
376         SkFlagInfo* info = new SkFlagInfo(name, nullptr, kUint_FlagType, helpString, nullptr);
377         info->fUintValue = pUint;
378         *info->fUintValue = info->fDefaultUint = defaultValue;
379         return true;
380     }
381 
CreateUintFlag(const char * name,const char * shortName,uint32_t * pUint,uint32_t defaultValue,const char * helpString)382     static bool CreateUintFlag(const char* name, const char* shortName, uint32_t* pUint,
383                                uint32_t defaultValue, const char* helpString) {
384         SkFlagInfo* info = new SkFlagInfo(name, shortName, kUint_FlagType, helpString, nullptr);
385         info->fUintValue = pUint;
386         *info->fUintValue = info->fDefaultUint = defaultValue;
387         return true;
388     }
389 
390     /**
391      *  See comments for CreateBoolFlag.
392      */
CreateDoubleFlag(const char * name,double * pDouble,double defaultValue,const char * helpString)393     static bool CreateDoubleFlag(const char* name, double* pDouble,
394                                  double defaultValue, const char* helpString) {
395         SkFlagInfo* info = new SkFlagInfo(name, nullptr, kDouble_FlagType, helpString, nullptr);
396         info->fDoubleValue = pDouble;
397         *info->fDoubleValue = info->fDefaultDouble = defaultValue;
398         return true;
399     }
400 
401     /**
402      *  Returns true if the string matches this flag.
403      *  For a boolean flag, also sets the value, since a boolean flag can be set in a number of ways
404      *  without looking at the following string:
405      *      --name
406      *      --noname
407      *      --name=true
408      *      --name=false
409      *      --name=1
410      *      --name=0
411      *      --name=TRUE
412      *      --name=FALSE
413      */
414     bool match(const char* string);
415 
getFlagType()416     FlagTypes getFlagType() const { return fFlagType; }
417 
resetStrings()418     void resetStrings() {
419         if (kString_FlagType == fFlagType) {
420             fStrings->reset();
421         } else {
422             SkDEBUGFAIL("Can only call resetStrings on kString_FlagType");
423         }
424     }
425 
append(const char * string)426     void append(const char* string) {
427         if (kString_FlagType == fFlagType) {
428             fStrings->append(string);
429         } else {
430             SkDEBUGFAIL("Can only append to kString_FlagType");
431         }
432     }
433 
setInt(int32_t value)434     void setInt(int32_t value) {
435         if (kInt_FlagType == fFlagType) {
436             *fIntValue = value;
437         } else {
438             SkDEBUGFAIL("Can only call setInt on kInt_FlagType");
439         }
440     }
441 
setUint(uint32_t value)442     void setUint(uint32_t value) {
443         if (kUint_FlagType == fFlagType) {
444             *fUintValue = value;
445         } else {
446             SkDEBUGFAIL("Can only call setUint on kUint_FlagType");
447         }
448     }
449 
setDouble(double value)450     void setDouble(double value) {
451         if (kDouble_FlagType == fFlagType) {
452             *fDoubleValue = value;
453         } else {
454             SkDEBUGFAIL("Can only call setDouble on kDouble_FlagType");
455         }
456     }
457 
setBool(bool value)458     void setBool(bool value) {
459         if (kBool_FlagType == fFlagType) {
460             *fBoolValue = value;
461         } else {
462             SkDEBUGFAIL("Can only call setBool on kBool_FlagType");
463         }
464     }
465 
next()466     SkFlagInfo* next() { return fNext; }
467 
name()468     const SkString& name() const { return fName; }
469 
shortName()470     const SkString& shortName() const { return fShortName; }
471 
help()472     const SkString& help() const { return fHelpString; }
extendedHelp()473     const SkString& extendedHelp() const { return fExtendedHelpString; }
474 
defaultValue()475     SkString defaultValue() const {
476         SkString result;
477         switch (fFlagType) {
478             case SkFlagInfo::kBool_FlagType:
479                 result.printf("%s", fDefaultBool ? "true" : "false");
480                 break;
481             case SkFlagInfo::kString_FlagType:
482                 return fDefaultString;
483             case SkFlagInfo::kInt_FlagType:
484                 result.printf("%i", fDefaultInt);
485                 break;
486             case SkFlagInfo::kUint_FlagType:
487                 result.printf("0x%08x", fDefaultUint);
488                 break;
489             case SkFlagInfo::kDouble_FlagType:
490                 result.printf("%2.2f", fDefaultDouble);
491                 break;
492             default:
493                 SkDEBUGFAIL("Invalid flag type");
494         }
495         return result;
496     }
497 
typeAsString()498     SkString typeAsString() const {
499         switch (fFlagType) {
500             case SkFlagInfo::kBool_FlagType:
501                 return SkString("bool");
502             case SkFlagInfo::kString_FlagType:
503                 return SkString("string");
504             case SkFlagInfo::kInt_FlagType:
505                 return SkString("int");
506             case SkFlagInfo::kUint_FlagType:
507                 return SkString("uint");
508             case SkFlagInfo::kDouble_FlagType:
509                 return SkString("double");
510             default:
511                 SkDEBUGFAIL("Invalid flag type");
512                 return SkString();
513         }
514     }
515 
516 private:
SkFlagInfo(const char * name,const char * shortName,FlagTypes type,const char * helpString,const char * extendedHelpString)517     SkFlagInfo(const char* name, const char* shortName, FlagTypes type, const char* helpString,
518                const char* extendedHelpString)
519         : fName(name)
520         , fShortName(shortName)
521         , fFlagType(type)
522         , fHelpString(helpString)
523         , fExtendedHelpString(extendedHelpString)
524         , fBoolValue(nullptr)
525         , fDefaultBool(false)
526         , fIntValue(nullptr)
527         , fDefaultInt(0)
528         , fUintValue(nullptr)
529         , fDefaultUint(0)
530         , fDoubleValue(nullptr)
531         , fDefaultDouble(0)
532         , fStrings(nullptr) {
533         fNext = SkCommandLineFlags::gHead;
534         SkCommandLineFlags::gHead = this;
535         SkASSERT(name && strlen(name) > 1);
536         SkASSERT(nullptr == shortName || 1 == strlen(shortName));
537     }
538 
539     /**
540      *  Set a StringArray to hold the values stored in defaultStrings.
541      *  @param array The StringArray to modify.
542      *  @param defaultStrings Space separated list of strings that should be inserted into array
543      *      individually.
544      */
545     static void SetDefaultStrings(SkCommandLineFlags::StringArray* array,
546                                   const char* defaultStrings);
547 
548     // Name of the flag, without initial dashes
549     SkString             fName;
550     SkString             fShortName;
551     FlagTypes            fFlagType;
552     SkString             fHelpString;
553     SkString             fExtendedHelpString;
554     bool*                fBoolValue;
555     bool                 fDefaultBool;
556     int32_t*             fIntValue;
557     int32_t              fDefaultInt;
558     uint32_t*            fUintValue;
559     uint32_t             fDefaultUint;
560     double*              fDoubleValue;
561     double               fDefaultDouble;
562     SkCommandLineFlags::StringArray* fStrings;
563     // Both for the help string and in case fStrings is empty.
564     SkString             fDefaultString;
565 
566     // In order to keep a linked list.
567     SkFlagInfo*          fNext;
568 };
569 #endif // SK_COMMAND_LINE_FLAGS_H
570