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 "SkString.h"
13 #include "SkStream.h"
14 
15 #include "SkTDict.h"
16 #include "SkTArray.h"
17 
18 /** \class SkRTConfBase
19     Non-templated base class for the runtime configs
20 */
21 
22 class SkRTConfBase {
23 public:
SkRTConfBase(const char * name)24     SkRTConfBase(const char *name) : fName(name) {}
~SkRTConfBase()25     virtual ~SkRTConfBase() {}
getName()26     virtual const char *getName() const { return fName.c_str(); }
27     virtual bool isDefault() const = 0;
28     virtual void print(SkWStream *o) const = 0;
29     virtual bool equals(const SkRTConfBase *conf) const = 0;
30 protected:
31     SkString fName;
32 };
33 
34 /** \class SkRTConf
35     A class to provide runtime configurability.
36 */
37 template<typename T> class SkRTConf: public SkRTConfBase {
38 public:
39     SkRTConf(const char *name, const T &defaultValue, const char *description);
40     operator const T&() const { return fValue; }
41     void print(SkWStream *o) const;
42     bool equals(const SkRTConfBase *conf) const;
isDefault()43     bool isDefault() const { return fDefault == fValue; }
set(const T & value)44     void set(const T& value) { fValue = value; }
45 protected:
46     void doPrint(char *s) const;
47 
48     T        fValue;
49     T        fDefault;
50     SkString fDescription;
51 };
52 
53 #ifdef SK_DEVELOPER
54 #define SK_CONF_DECLARE(confType, varName, confName, defaultValue, description) static SkRTConf<confType> varName(confName, defaultValue, description)
55 #define SK_CONF_SET(confname, value) \
56     skRTConfRegistry().set(confname, value, true)
57 /* SK_CONF_TRY_SET() is like SK_CONF_SET(), but doesn't complain if
58    confname can't be found.  This is useful if the SK_CONF_DECLARE is
59    inside a source file whose linkage is dependent on the system. */
60 #define SK_CONF_TRY_SET(confname, value) \
61     skRTConfRegistry().set(confname, value, false)
62 #else
63 #define SK_CONF_DECLARE(confType, varName, confName, defaultValue, description) static confType varName = defaultValue
64 #define SK_CONF_SET(confname, value) (void) confname, (void) value
65 #define SK_CONF_TRY_SET(confname, value) (void) confname, (void) value
66 #endif
67 
68 /** \class SkRTConfRegistry
69     A class that maintains a systemwide registry of all runtime configuration
70     parameters.  Mainly used for printing them out and handling multiply-defined
71     knobs.
72 */
73 
74 class SkRTConfRegistry {
75 public:
76     SkRTConfRegistry();
77     ~SkRTConfRegistry();
78     void printAll(const char *fname = NULL) const;
79     bool hasNonDefault() const;
80     void printNonDefault(const char *fname = NULL) const;
81     const char *configFileLocation() const;
82     void possiblyDumpFile() const;
83     void validate() const;
84     template <typename T> void set(const char *confname,
85                                    T value,
86                                    bool warnIfNotFound = true);
87 
88 private:
89     template<typename T> friend class SkRTConf;
90 
91     void registerConf(SkRTConfBase *conf);
92 
93     template <typename T> bool parse(const char *name, T* value);
94 
95     SkTDArray<SkString *> fConfigFileKeys, fConfigFileValues;
96     typedef SkTDict< SkTDArray<SkRTConfBase *> * > ConfMap;
97     ConfMap fConfs;
98 
99     template <typename T>
100     friend bool test_rt_conf_parse(SkRTConfRegistry*, const char* name, T* value);
101 };
102 
103 // our singleton registry
104 
105 SkRTConfRegistry &skRTConfRegistry();
106 
107 template<typename T>
SkRTConf(const char * name,const T & defaultValue,const char * description)108 SkRTConf<T>::SkRTConf(const char *name, const T &defaultValue, const char *description)
109     : SkRTConfBase(name)
110     , fValue(defaultValue)
111     , fDefault(defaultValue)
112     , fDescription(description) {
113 
114     T value;
115     if (skRTConfRegistry().parse(fName.c_str(), &value)) {
116         fValue = value;
117     }
118     skRTConfRegistry().registerConf(this);
119 }
120 
121 template<typename T>
print(SkWStream * o)122 void SkRTConf<T>::print(SkWStream *o) const {
123     char outline[200]; // should be ok because we specify a max. width for everything here.
124     char *outptr;
125     if (strlen(getName()) >= 30) {
126         o->writeText(getName());
127         o->writeText(" ");
128         outptr = &(outline[0]);
129     } else {
130         sprintf(outline, "%-30.30s", getName());
131         outptr = &(outline[30]);
132     }
133 
134     doPrint(outptr);
135     sprintf(outptr+30, " %.128s", fDescription.c_str());
136     for (size_t i = strlen(outline); i --> 0 && ' ' == outline[i];) {
137         outline[i] = '\0';
138     }
139     o->writeText(outline);
140 }
141 
142 template<typename T>
doPrint(char * s)143 void SkRTConf<T>::doPrint(char *s) const {
144     sprintf(s, "%-30.30s", "How do I print myself??");
145 }
146 
doPrint(char * s)147 template<> inline void SkRTConf<bool>::doPrint(char *s) const {
148     char tmp[30];
149     sprintf(tmp, "%s # [%s]", fValue ? "true" : "false", fDefault ? "true" : "false");
150     sprintf(s, "%-30.30s", tmp);
151 }
152 
doPrint(char * s)153 template<> inline void SkRTConf<int>::doPrint(char *s) const {
154     char tmp[30];
155     sprintf(tmp, "%d # [%d]", fValue, fDefault);
156     sprintf(s, "%-30.30s", tmp);
157 }
158 
doPrint(char * s)159 template<> inline void SkRTConf<unsigned int>::doPrint(char *s) const {
160     char tmp[30];
161     sprintf(tmp, "%u # [%u]", fValue, fDefault);
162     sprintf(s, "%-30.30s", tmp);
163 }
164 
doPrint(char * s)165 template<> inline void SkRTConf<float>::doPrint(char *s) const {
166     char tmp[30];
167     sprintf(tmp, "%6.6f # [%6.6f]", fValue, fDefault);
168     sprintf(s, "%-30.30s", tmp);
169 }
170 
doPrint(char * s)171 template<> inline void SkRTConf<double>::doPrint(char *s) const {
172     char tmp[30];
173     sprintf(tmp, "%6.6f # [%6.6f]", fValue, fDefault);
174     sprintf(s, "%-30.30s", tmp);
175 }
176 
doPrint(char * s)177 template<> inline void SkRTConf<const char *>::doPrint(char *s) const {
178     char tmp[30];
179     sprintf(tmp, "%s # [%s]", fValue, fDefault);
180     sprintf(s, "%-30.30s", tmp);
181 }
182 
183 template<typename T>
equals(const SkRTConfBase * conf)184 bool SkRTConf<T>::equals(const SkRTConfBase *conf) const {
185     // static_cast here is okay because there's only one kind of child class.
186     const SkRTConf<T> *child_pointer = static_cast<const SkRTConf<T> *>(conf);
187     return child_pointer &&
188            fName == child_pointer->fName &&
189            fDescription == child_pointer->fDescription &&
190            fValue == child_pointer->fValue &&
191            fDefault == child_pointer->fDefault;
192 }
193 
194 #endif
195