Merge bitcoin#10901: Fix constness of ArgsManager methods

a622a17 Fix constness of ArgsManager methods (João Barbosa)

Pull request description:

  Make `cs_args` mutex mutable so that const methods can acquire it.

  There's also tiny performance improvement by avoiding two map lookups when retrieving an argument value.

Tree-SHA512: ece58469745f2743b4b643242b51889a3d9c5b76492ed70bb74d4e5b378fff59da79fc129e499da779bf9f488c9435dda17ad1f3a804c1c30f56af422389e8bd

Author: MarcoFalke

src/util.cpp

@@ -419,49 +419,48 @@ void ArgsManager::ParseParameters(int argc, const char* const argv[])
     }
 }
 
-std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg)
+std::vector<std::string> ArgsManager::GetArgs(const std::string& strArg) const
 {
     LOCK(cs_args);
-    if (IsArgSet(strArg))
-        return mapMultiArgs.at(strArg);
+    auto it = mapMultiArgs.find(strArg);
+    if (it != mapMultiArgs.end()) return it->second;
     return {};
 }
 
-bool ArgsManager::IsArgSet(const std::string& strArg)
+bool ArgsManager::IsArgSet(const std::string& strArg) const
 {
     LOCK(cs_args);
     return mapArgs.count(strArg);
 }
 
-std::string ArgsManager::GetArg(const std::string& strArg, const std::string& strDefault)
+std::string ArgsManager::GetArg(const std::string& strArg, const std::string& strDefault) const
 {
     LOCK(cs_args);
-    if (mapArgs.count(strArg))
-        return mapArgs[strArg];
+    auto it = mapArgs.find(strArg);
+    if (it != mapArgs.end()) return it->second;
     return strDefault;
 }
 
-int64_t ArgsManager::GetArg(const std::string& strArg, int64_t nDefault)
+int64_t ArgsManager::GetArg(const std::string& strArg, int64_t nDefault) const
 {
     LOCK(cs_args);
-    if (mapArgs.count(strArg))
-        return atoi64(mapArgs[strArg]);
+    auto it = mapArgs.find(strArg);
+    if (it != mapArgs.end()) return atoi64(it->second);
     return nDefault;
 }
 
-bool ArgsManager::GetBoolArg(const std::string& strArg, bool fDefault)
+bool ArgsManager::GetBoolArg(const std::string& strArg, bool fDefault) const
 {
     LOCK(cs_args);
-    if (mapArgs.count(strArg))
-        return InterpretBool(mapArgs[strArg]);
+    auto it = mapArgs.find(strArg);
+    if (it != mapArgs.end()) return InterpretBool(it->second);
     return fDefault;
 }
 
 bool ArgsManager::SoftSetArg(const std::string& strArg, const std::string& strValue)
 {
     LOCK(cs_args);
-    if (mapArgs.count(strArg))
-        return false;
+    if (IsArgSet(strArg)) return false;
     ForceSetArg(strArg, strValue);
     return true;
 }
@@ -478,8 +477,7 @@ void ArgsManager::ForceSetArg(const std::string& strArg, const std::string& strV
 {
     LOCK(cs_args);
     mapArgs[strArg] = strValue;
-    mapMultiArgs[strArg].clear();
-    mapMultiArgs[strArg].push_back(strValue);
+    mapMultiArgs[strArg] = {strValue};
 }
 
 

src/util.h

@@ -195,21 +195,28 @@ inline bool IsSwitchChar(char c)
 class ArgsManager
 {
 protected:
-    CCriticalSection cs_args;
+    mutable CCriticalSection cs_args;
     std::map<std::string, std::string> mapArgs;
-    std::map<std::string, std::vector<std::string> > mapMultiArgs;
+    std::map<std::string, std::vector<std::string>> mapMultiArgs;
 public:
     void ParseParameters(int argc, const char*const argv[]);
     void ReadConfigFile(const std::string& confPath);
-    std::vector<std::string> GetArgs(const std::string& strArg);
+
+    /**
+     * Return a vector of strings of the given argument
+     *
+     * @param strArg Argument to get (e.g. "-foo")
+     * @return command-line arguments
+     */
+    std::vector<std::string> GetArgs(const std::string& strArg) const;
 
     /**
      * Return true if the given argument has been manually set
      *
      * @param strArg Argument to get (e.g. "-foo")
      * @return true if the argument has been set
      */
-    bool IsArgSet(const std::string& strArg);
+    bool IsArgSet(const std::string& strArg) const;
 
     /**
      * Return string argument or default value
@@ -218,7 +225,7 @@ class ArgsManager
      * @param strDefault (e.g. "1")
      * @return command-line argument or default value
      */
-    std::string GetArg(const std::string& strArg, const std::string& strDefault);
+    std::string GetArg(const std::string& strArg, const std::string& strDefault) const;
 
     /**
      * Return integer argument or default value
@@ -227,7 +234,7 @@ class ArgsManager
      * @param nDefault (e.g. 1)
      * @return command-line argument (0 if invalid number) or default value
      */
-    int64_t GetArg(const std::string& strArg, int64_t nDefault);
+    int64_t GetArg(const std::string& strArg, int64_t nDefault) const;
 
     /**
      * Return boolean argument or default value
@@ -236,7 +243,7 @@ class ArgsManager
      * @param fDefault (true or false)
      * @return command-line argument or default value
      */
-    bool GetBoolArg(const std::string& strArg, bool fDefault);
+    bool GetBoolArg(const std::string& strArg, bool fDefault) const;
 
     /**
      * Set an argument if it doesn't already have a value