Move configuration to core library

Make it clearer what is protocol handling and what is just general
plumbing.

This is one step of several.

3 files changed, 678 insertions, 1 deletions

diff --git a/common/core/CMakeLists.txt b/common/core/CMakeLists.txt
index bbf37ff2..199ad429 100644
--- a/common/core/CMakeLists.txt
+++ b/common/core/CMakeLists.txt
@@ -1,9 +1,10 @@
 add_library(core STATIC
+  Configuration.cxx
   Exception.cxx
   Region.cxx
   util.cxx)
 
-target_link_libraries(core rfb)
+target_link_libraries(core os rfb)
 target_include_directories(core PUBLIC ${CMAKE_SOURCE_DIR}/common)
 target_include_directories(core SYSTEM PUBLIC ${PIXMAN_INCLUDE_DIRS})
 target_link_libraries(core ${PIXMAN_LIBRARIES})
diff --git a/common/core/Configuration.cxx b/common/core/Configuration.cxx
new file mode 100644
index 00000000..12d74bb6
--- /dev/null
+++ b/common/core/Configuration.cxx
@@ -0,0 +1,451 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2004-2005 Cendio AB.
+ * Copyright 2017 Peter Astrand <astrand@cendio.se> for Cendio AB
+ * Copyright 2011-2022 Pierre Ossman for Cendio AB
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+// -=- Configuration.cxx
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+
+#include <algorithm>
+#include <stdexcept>
+
+#include <core/Configuration.h>
+#include <core/util.h>
+
+#include <rfb/LogWriter.h>
+
+#include <rdr/HexOutStream.h>
+#include <rdr/HexInStream.h>
+
+// Temporary during transition to new structure:
+using namespace core;
+using namespace rfb;
+
+static LogWriter vlog("Config");
+
+
+// -=- The Global Configuration object
+Configuration* Configuration::global_ = nullptr;
+
+Configuration* Configuration::global() {
+  if (!global_)
+    global_ = new Configuration();
+  return global_;
+}
+
+// -=- Configuration implementation
+
+bool Configuration::set(const char* paramName, const char* val,
+                        bool immutable)
+{
+  for (VoidParameter* current: params) {
+    if (strcasecmp(current->getName(), paramName) == 0) {
+      bool b = current->setParam(val);
+      if (b && immutable) 
+	current->setImmutable();
+      return b;
+    }
+  }
+  return false;
+}
+
+VoidParameter* Configuration::get(const char* param)
+{
+  for (VoidParameter* current: params) {
+    if (strcasecmp(current->getName(), param) == 0)
+      return current;
+  }
+  return nullptr;
+}
+
+void Configuration::list(int width, int nameWidth) {
+  for (VoidParameter* current: params) {
+    std::string def_str = current->getDefaultStr();
+    const char* desc = current->getDescription();
+    fprintf(stderr,"  %-*s -", nameWidth, current->getName());
+    int column = strlen(current->getName());
+    if (column < nameWidth) column = nameWidth;
+    column += 4;
+    while (true) {
+      const char* s = strchr(desc, ' ');
+      int wordLen;
+      if (s) wordLen = s-desc;
+      else wordLen = strlen(desc);
+
+      if (column + wordLen + 1 > width) {
+        fprintf(stderr,"\n%*s",nameWidth+4,"");
+        column = nameWidth+4;
+      }
+      fprintf(stderr," %.*s",wordLen,desc);
+      column += wordLen + 1;
+      desc += wordLen + 1;
+      if (!s) break;
+    }
+
+    if (!def_str.empty()) {
+      if (column + (int)def_str.size() + 11 > width)
+        fprintf(stderr,"\n%*s",nameWidth+4,"");
+      fprintf(stderr," (default=%s)\n",def_str.c_str());
+    } else {
+      fprintf(stderr,"\n");
+    }
+  }
+}
+
+
+bool Configuration::remove(const char* param) {
+  std::list<VoidParameter*>::iterator iter;
+
+  iter = std::find_if(params.begin(), params.end(),
+                      [param](VoidParameter* p) {
+                        return strcasecmp(p->getName(), param) == 0;
+                      });
+  if (iter == params.end())
+    return false;
+
+  params.erase(iter);
+  return true;
+}
+
+int Configuration::handleArg(int argc, char* argv[], int index)
+{
+  std::string param, val;
+  const char* equal = strchr(argv[index], '=');
+
+  if (equal == argv[index])
+    return 0;
+
+  if (equal) {
+    param.assign(argv[index], equal-argv[index]);
+    val.assign(equal+1);
+  } else {
+    param.assign(argv[index]);
+  }
+
+  if ((param.length() > 0) && (param[0] == '-')) {
+    // allow gnu-style --<option>
+    if ((param.length() > 1) && (param[1] == '-'))
+      param = param.substr(2);
+    else
+      param = param.substr(1);
+  } else {
+    // All command line arguments need either an initial '-', or an '='
+    if (!equal)
+      return 0;
+  }
+
+  if (equal)
+    return set(param.c_str(), val.c_str()) ? 1 : 0;
+
+  for (VoidParameter* current: params) {
+    if (strcasecmp(current->getName(), param.c_str()) != 0)
+      continue;
+
+    // We need to resolve an ambiguity for booleans
+    if (dynamic_cast<BoolParameter*>(current) != nullptr) {
+      if (index+1 < argc) {
+        // FIXME: Should not duplicate the list of values here
+        if ((strcasecmp(argv[index+1], "0") == 0) ||
+            (strcasecmp(argv[index+1], "1") == 0) ||
+            (strcasecmp(argv[index+1], "on") == 0) ||
+            (strcasecmp(argv[index+1], "off") == 0) ||
+            (strcasecmp(argv[index+1], "true") == 0) ||
+            (strcasecmp(argv[index+1], "false") == 0) ||
+            (strcasecmp(argv[index+1], "yes") == 0) ||
+            (strcasecmp(argv[index+1], "no") == 0)) {
+            return current->setParam(argv[index+1]) ? 2 : 0;
+        }
+      }
+    }
+
+    if (current->setParam())
+      return 1;
+
+    if (index+1 >= argc)
+      return 0;
+
+    return current->setParam(argv[index+1]) ? 2 : 0;
+  }
+
+  return 0;
+}
+
+
+// -=- VoidParameter
+
+VoidParameter::VoidParameter(const char* name_, const char* desc_)
+  : immutable(false), name(name_), description(desc_)
+{
+  Configuration *conf;
+
+  conf = Configuration::global();
+  conf->params.push_back(this);
+  conf->params.sort([](const VoidParameter* a, const VoidParameter* b) {
+    return strcasecmp(a->getName(), b->getName()) < 0;
+  });
+}
+
+VoidParameter::~VoidParameter() {
+  Configuration *conf;
+
+  conf = Configuration::global();
+  conf->params.remove(this);
+}
+
+const char*
+VoidParameter::getName() const {
+  return name;
+}
+
+const char*
+VoidParameter::getDescription() const {
+  return description;
+}
+
+bool VoidParameter::setParam() {
+  return false;
+}
+
+bool VoidParameter::isDefault() const {
+  return getDefaultStr() == getValueStr();
+}
+
+void
+VoidParameter::setImmutable() {
+  vlog.debug("Set immutable %s", getName());
+  immutable = true;
+}
+
+// -=- AliasParameter
+
+AliasParameter::AliasParameter(const char* name_, const char* desc_,
+                               VoidParameter* param_)
+  : VoidParameter(name_, desc_), param(param_) {
+}
+
+bool
+AliasParameter::setParam(const char* v) {
+  return param->setParam(v);
+}
+
+bool AliasParameter::setParam() {
+  return param->setParam();
+}
+
+std::string AliasParameter::getDefaultStr() const {
+  return "";
+}
+
+std::string AliasParameter::getValueStr() const {
+  return param->getValueStr();
+}
+
+void
+AliasParameter::setImmutable() {
+  vlog.debug("Set immutable %s (Alias)", getName());
+  param->setImmutable();
+}
+
+
+// -=- BoolParameter
+
+BoolParameter::BoolParameter(const char* name_, const char* desc_, bool v)
+: VoidParameter(name_, desc_), value(v), def_value(v) {
+}
+
+bool
+BoolParameter::setParam(const char* v) {
+  if (immutable) return true;
+
+  if (*v == 0 || strcasecmp(v, "1") == 0 || strcasecmp(v, "on") == 0
+      || strcasecmp(v, "true") == 0 || strcasecmp(v, "yes") == 0)
+    setParam(true);
+  else if (strcasecmp(v, "0") == 0 || strcasecmp(v, "off") == 0
+           || strcasecmp(v, "false") == 0 || strcasecmp(v, "no") == 0)
+    setParam(false);
+  else {
+    vlog.error("Bool parameter %s: Invalid value '%s'", getName(), v);
+    return false;
+  }
+
+  return true;
+}
+
+bool BoolParameter::setParam() {
+  setParam(true);
+  return true;
+}
+
+void BoolParameter::setParam(bool b) {
+  if (immutable) return;
+  value = b;
+  vlog.debug("Set %s(Bool) to %s", getName(), getValueStr().c_str());
+}
+
+std::string BoolParameter::getDefaultStr() const {
+  return def_value ? "on" : "off";
+}
+
+std::string BoolParameter::getValueStr() const {
+  return value ? "on" : "off";
+}
+
+BoolParameter::operator bool() const {
+  return value;
+}
+
+// -=- IntParameter
+
+IntParameter::IntParameter(const char* name_, const char* desc_, int v,
+                           int minValue_, int maxValue_)
+  : VoidParameter(name_, desc_), value(v), def_value(v),
+    minValue(minValue_), maxValue(maxValue_)
+{
+}
+
+bool
+IntParameter::setParam(const char* v) {
+  if (immutable) return true;
+  return setParam(strtol(v, nullptr, 0));
+}
+
+bool
+IntParameter::setParam(int v) {
+  if (immutable) return true;
+  vlog.debug("Set %s(Int) to %d", getName(), v);
+  if (v < minValue || v > maxValue)
+    return false;
+  value = v;
+  return true;
+}
+
+std::string IntParameter::getDefaultStr() const {
+  char result[16];
+  sprintf(result, "%d", def_value);
+  return result;
+}
+
+std::string IntParameter::getValueStr() const {
+  char result[16];
+  sprintf(result, "%d", value);
+  return result;
+}
+
+IntParameter::operator int() const {
+  return value;
+}
+
+// -=- StringParameter
+
+StringParameter::StringParameter(const char* name_, const char* desc_,
+                                 const char* v)
+  : VoidParameter(name_, desc_), value(v), def_value(v)
+{
+  if (!v) {
+    vlog.error("Default value <null> for %s not allowed",name_);
+    throw std::invalid_argument("Default value <null> not allowed");
+  }
+}
+
+bool StringParameter::setParam(const char* v) {
+  if (immutable) return true;
+  if (!v)
+    throw std::invalid_argument("setParam(<null>) not allowed");
+  vlog.debug("Set %s(String) to %s", getName(), v);
+  value = v;
+  return true;
+}
+
+std::string StringParameter::getDefaultStr() const {
+  return def_value;
+}
+
+std::string StringParameter::getValueStr() const {
+  return value;
+}
+
+StringParameter::operator const char *() const {
+  return value.c_str();
+}
+
+// -=- BinaryParameter
+
+BinaryParameter::BinaryParameter(const char* name_, const char* desc_,
+				 const uint8_t* v, size_t l)
+: VoidParameter(name_, desc_),
+  value(nullptr), length(0), def_value(nullptr), def_length(0) {
+  if (l) {
+    assert(v);
+    value = new uint8_t[l];
+    length = l;
+    memcpy(value, v, l);
+    def_value = new uint8_t[l];
+    def_length = l;
+    memcpy(def_value, v, l);
+  }
+}
+BinaryParameter::~BinaryParameter() {
+  delete [] value;
+  delete [] def_value;
+}
+
+bool BinaryParameter::setParam(const char* v) {
+  if (immutable) return true;
+  std::vector<uint8_t> newValue = hexToBin(v, strlen(v));
+  if (newValue.empty() && strlen(v) > 0)
+    return false;
+  setParam(newValue.data(), newValue.size());
+  return true;
+}
+
+void BinaryParameter::setParam(const uint8_t* v, size_t len) {
+  if (immutable) return; 
+  vlog.debug("Set %s(Binary)", getName());
+  delete [] value;
+  value = nullptr;
+  length = 0;
+  if (len) {
+    assert(v);
+    value = new uint8_t[len];
+    length = len;
+    memcpy(value, v, len);
+  }
+}
+
+std::string BinaryParameter::getDefaultStr() const {
+  return binToHex(def_value, def_length);
+}
+
+std::string BinaryParameter::getValueStr() const {
+  return binToHex(value, length);
+}
+
+std::vector<uint8_t> BinaryParameter::getData() const {
+  std::vector<uint8_t> out(length);
+  memcpy(out.data(), value, length);
+  return out;
+}
diff --git a/common/core/Configuration.h b/common/core/Configuration.h
new file mode 100644
index 00000000..c724d9b8
--- /dev/null
+++ b/common/core/Configuration.h
@@ -0,0 +1,225 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright 2011-2022 Pierre Ossman for Cendio AB
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+// -=- Configuration.h
+//
+// This header defines a set of classes used to represent configuration
+// parameters of different types.  Instances of the different parameter
+// types are associated with instances of the Configuration class, and
+// are each given a unique name.  The Configuration class provides a
+// generic API through which parameters may be located by name and their
+// value set, thus removing the need to write platform-specific code.
+// Simply defining a new parameter and associating it with a Configuration
+// will allow it to be configured by the user.
+//
+// If no Configuration is specified when creating a Parameter, then the
+// global Configuration will be assumed.
+//
+// Configurations can be "chained" into groups.  Each group has a root
+// Configuration, a pointer to which should be passed to the constructors
+// of the other group members.  set() and get() operations called on the
+// root will iterate through all of the group's members.
+//
+// NB: On platforms that support Threading, locking is performed to protect
+//     complex parameter types from concurrent access (e.g. strings).
+// NB: NO LOCKING is performed when linking Configurations to groups
+//     or when adding Parameters to Configurations.
+
+#ifndef __CORE_CONFIGURATION_H__
+#define __CORE_CONFIGURATION_H__
+
+#include <limits.h>
+#include <stdint.h>
+
+#include <list>
+#include <string>
+#include <vector>
+
+namespace core {
+
+  class VoidParameter;
+
+  // -=- Configuration
+  //     Class used to access parameters.
+
+  class Configuration {
+  public:
+    // - Create a new Configuration object
+    Configuration() {}
+
+    // - Set named parameter to value
+    bool set(const char* param, const char* value, bool immutable=false);
+
+    // - Get named parameter
+    VoidParameter* get(const char* param);
+
+    // - List the parameters of this Configuration group
+    void list(int width=79, int nameWidth=10);
+
+    // - Remove a parameter from this Configuration group
+    bool remove(const char* param);
+
+    // - handleArg
+    //   Parse a command line argument into a parameter, returning how
+    //   many arguments were consumed
+    int handleArg(int argc, char* argv[], int index);
+
+
+    // - Iterate over all parameters
+    std::list<VoidParameter*>::iterator begin() { return params.begin(); }
+    std::list<VoidParameter*>::iterator end() { return params.end(); }
+
+
+    // - Get the Global Configuration object
+    //   NB: This call does NOT lock the Configuration system.
+    //       ALWAYS ensure that if you have ANY global Parameters,
+    //       then they are defined as global objects, to ensure that
+    //       global() is called when only the main thread is running.
+    static Configuration* global();
+
+    // - Container for process-wide Global parameters
+    static bool setParam(const char* param, const char* value, bool immutable=false) {
+      return global()->set(param, value, immutable);
+    }
+    static VoidParameter* getParam(const char* param) { return global()->get(param); }
+    static void listParams(int width=79, int nameWidth=10) {
+      global()->list(width, nameWidth);
+    }
+    static bool removeParam(const char* param) {
+      return global()->remove(param);
+    }
+    static int handleParamArg(int argc, char* argv[], int index) {
+      return global()->handleArg(argc, argv, index);
+    }
+
+  private:
+    friend class VoidParameter;
+
+    // - List of Parameters
+    std::list<VoidParameter*> params;
+
+    // The process-wide, Global Configuration object
+    static Configuration* global_;
+  };
+
+  // -=- VoidParameter
+  //     Configuration parameter base-class.
+
+  class VoidParameter {
+  public:
+    VoidParameter(const char* name_, const char* desc_);
+    virtual  ~VoidParameter();
+    const char* getName() const;
+    const char* getDescription() const;
+
+    virtual bool setParam(const char* value)  = 0;
+    virtual bool setParam();
+    virtual std::string getDefaultStr() const = 0;
+    virtual std::string getValueStr() const = 0;
+
+    virtual bool isDefault() const;
+
+    virtual void setImmutable();
+
+  protected:
+    friend class Configuration;
+
+    VoidParameter* _next;
+    bool immutable;
+    const char* name;
+    const char* description;
+  };
+
+  class AliasParameter : public VoidParameter {
+  public:
+    AliasParameter(const char* name_, const char* desc_,VoidParameter* param_);
+    bool setParam(const char* value) override;
+    bool setParam() override;
+    std::string getDefaultStr() const override;
+    std::string getValueStr() const override;
+    void setImmutable() override;
+  private:
+    VoidParameter* param;
+  };
+
+  class BoolParameter : public VoidParameter {
+  public:
+    BoolParameter(const char* name_, const char* desc_, bool v);
+    bool setParam(const char* value) override;
+    bool setParam() override;
+    virtual void setParam(bool b);
+    std::string getDefaultStr() const override;
+    std::string getValueStr() const override;
+    operator bool() const;
+  protected:
+    bool value;
+    bool def_value;
+  };
+
+  class IntParameter : public VoidParameter {
+  public:
+    IntParameter(const char* name_, const char* desc_, int v,
+                 int minValue=INT_MIN, int maxValue=INT_MAX);
+    using VoidParameter::setParam;
+    bool setParam(const char* value) override;
+    virtual bool setParam(int v);
+    std::string getDefaultStr() const override;
+    std::string getValueStr() const override;
+    operator int() const;
+  protected:
+    int value;
+    int def_value;
+    int minValue, maxValue;
+  };
+
+  class StringParameter : public VoidParameter {
+  public:
+    StringParameter(const char* name_, const char* desc_, const char* v);
+    bool setParam(const char* value) override;
+    std::string getDefaultStr() const override;
+    std::string getValueStr() const override;
+    operator const char*() const;
+  protected:
+    std::string value;
+    std::string def_value;
+  };
+
+  class BinaryParameter : public VoidParameter {
+  public:
+    BinaryParameter(const char* name_, const char* desc_,
+                    const uint8_t* v, size_t l);
+    using VoidParameter::setParam;
+    ~BinaryParameter() override;
+    bool setParam(const char* value) override;
+    virtual void setParam(const uint8_t* v, size_t l);
+    std::string getDefaultStr() const override;
+    std::string getValueStr() const override;
+
+    std::vector<uint8_t> getData() const;
+
+  protected:
+    uint8_t* value;
+    size_t length;
+    uint8_t* def_value;
+    size_t def_length;
+  };
+
+};
+
+#endif // __CORE_CONFIGURATION_H__