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 
9 #ifndef SkRTConf_DEFINED
10 #define SkRTConf_DEFINED
11 
12 #include "../private/SkTDArray.h"
13 #include "../private/SkTDict.h"
14 #include "SkString.h"
15 #include "SkStream.h"
16 
17 /** \class SkRTConfBase
18     Non-templated base class for the runtime configs
19 */
20 
21 class SkRTConfBase {
22 public:
SkRTConfBase(const char * name)23     SkRTConfBase(const char *name) : fName(name) {}
~SkRTConfBase()24     virtual ~SkRTConfBase() {}
getName()25     virtual const char *getName() const { return fName.c_str(); }
26     virtual bool isDefault() const = 0;
27     virtual void print(SkWStream *o) const = 0;
28     virtual bool equals(const SkRTConfBase *conf) const = 0;
29 protected:
30     SkString fName;
31 };
32 
33 /** \class SkRTConf
34     A class to provide runtime configurability.
35 */
36 template<typename T> class SkRTConf: public SkRTConfBase {
37 public:
38     SkRTConf(const char *name, const T &defaultValue, const char *description);
39     operator const T&() const { return fValue; }
40     void print(SkWStream *o) const;
41     bool equals(const SkRTConfBase *conf) const;
isDefault()42     bool isDefault() const { return fDefault == fValue; }
set(const T & value)43     void set(const T& value) { fValue = value; }
44 protected:
45     void doPrint(char *s) const;
46 
47     T        fValue;
48     T        fDefault;
49     SkString fDescription;
50 };
51 
52 #ifdef SK_DEVELOPER
53 #define SK_CONF_DECLARE(confType, varName, confName, defaultValue, description) static SkRTConf<confType> varName(confName, defaultValue, description)
54 #define SK_CONF_SET(confname, value) \
55     skRTConfRegistry().set(confname, value, true)
56 /* SK_CONF_TRY_SET() is like SK_CONF_SET(), but doesn't complain if
57    confname can't be found.  This is useful if the SK_CONF_DECLARE is
58    inside a source file whose linkage is dependent on the system. */
59 #define SK_CONF_TRY_SET(confname, value) \
60     skRTConfRegistry().set(confname, value, false)
61 #else
62 #define SK_CONF_DECLARE(confType, varName, confName, defaultValue, description) static confType varName = defaultValue
63 #define SK_CONF_SET(confname, value) (void) confname, (void) value
64 #define SK_CONF_TRY_SET(confname, value) (void) confname, (void) value
65 #endif
66 
67 /** \class SkRTConfRegistry
68     A class that maintains a systemwide registry of all runtime configuration
69     parameters.  Mainly used for printing them out and handling multiply-defined
70     knobs.
71 */
72 
73 class SkRTConfRegistry {
74 public:
75     SkRTConfRegistry();
76     ~SkRTConfRegistry();
77     void printAll(const char *fname = NULL) const;
78     bool hasNonDefault() const;
79     void printNonDefault(const char *fname = NULL) const;
80     const char *configFileLocation() const;
81     void possiblyDumpFile() const;
82     void validate() const;
83     template <typename T> void set(const char *confname,
84                                    T value,
85                                    bool warnIfNotFound = true);
86 
87 private:
88     template<typename T> friend class SkRTConf;
89 
90     void registerConf(SkRTConfBase *conf);
91 
92     template <typename T> bool parse(const char *name, T* value);
93 
94     SkTDArray<SkString *> fConfigFileKeys, fConfigFileValues;
95     typedef SkTDict< SkTDArray<SkRTConfBase *> * > ConfMap;
96     ConfMap fConfs;
97 
98     template <typename T>
99     friend bool test_rt_conf_parse(SkRTConfRegistry*, const char* name, T* value);
100 };
101 
102 // our singleton registry
103 
104 SkRTConfRegistry &skRTConfRegistry();
105 
106 template<typename T>
SkRTConf(const char * name,const T & defaultValue,const char * description)107 SkRTConf<T>::SkRTConf(const char *name, const T &defaultValue, const char *description)
108     : SkRTConfBase(name)
109     , fValue(defaultValue)
110     , fDefault(defaultValue)
111     , fDescription(description) {
112 
113     T value;
114     if (skRTConfRegistry().parse(fName.c_str(), &value)) {
115         fValue = value;
116     }
117     skRTConfRegistry().registerConf(this);
118 }
119 
120 template<typename T>
print(SkWStream * o)121 void SkRTConf<T>::print(SkWStream *o) const {
122     char outline[200]; // should be ok because we specify a max. width for everything here.
123     char *outptr;
124     if (strlen(getName()) >= 30) {
125         o->writeText(getName());
126         o->writeText(" ");
127         outptr = &(outline[0]);
128     } else {
129         sprintf(outline, "%-30.30s", getName());
130         outptr = &(outline[30]);
131     }
132 
133     doPrint(outptr);
134     sprintf(outptr+30, " %.128s", fDescription.c_str());
135     for (size_t i = strlen(outline); i --> 0 && ' ' == outline[i];) {
136         outline[i] = '\0';
137     }
138     o->writeText(outline);
139 }
140 
141 template<typename T>
doPrint(char * s)142 void SkRTConf<T>::doPrint(char *s) const {
143     sprintf(s, "%-30.30s", "How do I print myself??");
144 }
145 
doPrint(char * s)146 template<> inline void SkRTConf<bool>::doPrint(char *s) const {
147     char tmp[30];
148     sprintf(tmp, "%s # [%s]", fValue ? "true" : "false", fDefault ? "true" : "false");
149     sprintf(s, "%-30.30s", tmp);
150 }
151 
doPrint(char * s)152 template<> inline void SkRTConf<int>::doPrint(char *s) const {
153     char tmp[30];
154     sprintf(tmp, "%d # [%d]", fValue, fDefault);
155     sprintf(s, "%-30.30s", tmp);
156 }
157 
doPrint(char * s)158 template<> inline void SkRTConf<unsigned int>::doPrint(char *s) const {
159     char tmp[30];
160     sprintf(tmp, "%u # [%u]", fValue, fDefault);
161     sprintf(s, "%-30.30s", tmp);
162 }
163 
doPrint(char * s)164 template<> inline void SkRTConf<float>::doPrint(char *s) const {
165     char tmp[30];
166     sprintf(tmp, "%6.6f # [%6.6f]", fValue, fDefault);
167     sprintf(s, "%-30.30s", tmp);
168 }
169 
doPrint(char * s)170 template<> inline void SkRTConf<double>::doPrint(char *s) const {
171     char tmp[30];
172     sprintf(tmp, "%6.6f # [%6.6f]", fValue, fDefault);
173     sprintf(s, "%-30.30s", tmp);
174 }
175 
doPrint(char * s)176 template<> inline void SkRTConf<const char *>::doPrint(char *s) const {
177     char tmp[30];
178     sprintf(tmp, "%s # [%s]", fValue, fDefault);
179     sprintf(s, "%-30.30s", tmp);
180 }
181 
182 template<typename T>
equals(const SkRTConfBase * conf)183 bool SkRTConf<T>::equals(const SkRTConfBase *conf) const {
184     // static_cast here is okay because there's only one kind of child class.
185     const SkRTConf<T> *child_pointer = static_cast<const SkRTConf<T> *>(conf);
186     return child_pointer &&
187            fName == child_pointer->fName &&
188            fDescription == child_pointer->fDescription &&
189            fValue == child_pointer->fValue &&
190            fDefault == child_pointer->fDefault;
191 }
192 
193 #endif
194