KasmVNC/common/rfb/Configuration.h
Pierre Ossman 259f1055cb Use size_t for lengths in stream objects
Provides safety against them accidentally becoming negative because
of bugs in the calculations.

Also does the same to CharArray and friends as they were strongly
connection to the stream objects.
2020-09-21 12:55:59 +03:00

314 lines
10 KiB
C++

/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
*
* 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 __RFB_CONFIGURATION_H__
#define __RFB_CONFIGURATION_H__
#include <rfb/util.h>
namespace os { class Mutex; }
namespace rfb {
class VoidParameter;
struct ParameterIterator;
enum ConfigurationObject { ConfGlobal, ConfServer, ConfViewer };
// -=- Configuration
// Class used to access parameters.
class Configuration {
public:
// - Create a new Configuration object
Configuration(const char* name_) : name(strDup(name_)), head(0), _next(0) {}
// - Return the buffer containing the Configuration's name
const char* getName() const { return name.buf; }
// - Set named parameter to value
bool set(const char* param, const char* value, bool immutable=false);
// - Set parameter to value (separated by "=")
bool set(const char* config, bool immutable=false);
// - Set named parameter to value, with name truncated at len
bool set(const char* name, int len,
const char* val, bool immutable);
// - 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);
// - readFromFile
// Read configuration parameters from the specified file.
void readFromFile(const char* filename);
// - writeConfigToFile
// Write a new configuration parameters file, then mv it
// over the old file.
void writeToFile(const char* filename);
// - 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();
// Enable server/viewer specific parameters
static void enableServerParams() { global()->appendConfiguration(server()); }
static void enableViewerParams() { global()->appendConfiguration(viewer()); }
// - 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 bool setParam(const char* config, bool immutable=false) {
return global()->set(config, immutable);
}
static bool setParam(const char* name, int len,
const char* val, bool immutable) {
return global()->set(name, len, val, 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);
}
private:
friend class VoidParameter;
friend struct ParameterIterator;
// Name for this Configuration
CharArray name;
// - Pointer to first Parameter in this group
VoidParameter* head;
// Pointer to next Configuration in this group
Configuration* _next;
// The process-wide, Global Configuration object
static Configuration* global_;
// The server only Configuration object
static Configuration* server_;
// The viewer only Configuration object
static Configuration* viewer_;
// Get server/viewer specific configuration object
static Configuration* server();
static Configuration* viewer();
// Append configuration object to this instance.
// NOTE: conf instance can be only one configuration object
void appendConfiguration(Configuration *conf) {
conf->_next = _next; _next = conf;
}
};
// -=- VoidParameter
// Configuration parameter base-class.
class VoidParameter {
public:
VoidParameter(const char* name_, const char* desc_, ConfigurationObject co=ConfGlobal);
virtual ~VoidParameter();
const char* getName() const;
const char* getDescription() const;
virtual bool setParam(const char* value) = 0;
virtual bool setParam();
virtual char* getDefaultStr() const = 0;
virtual char* getValueStr() const = 0;
virtual bool isBool() const;
virtual void setImmutable();
protected:
friend class Configuration;
friend struct ParameterIterator;
VoidParameter* _next;
bool immutable;
const char* name;
const char* description;
os::Mutex* mutex;
};
class AliasParameter : public VoidParameter {
public:
AliasParameter(const char* name_, const char* desc_,VoidParameter* param_,
ConfigurationObject co=ConfGlobal);
virtual bool setParam(const char* value);
virtual bool setParam();
virtual char* getDefaultStr() const;
virtual char* getValueStr() const;
virtual bool isBool() const;
virtual void setImmutable();
private:
VoidParameter* param;
};
class BoolParameter : public VoidParameter {
public:
BoolParameter(const char* name_, const char* desc_, bool v,
ConfigurationObject co=ConfGlobal);
virtual bool setParam(const char* value);
virtual bool setParam();
virtual void setParam(bool b);
virtual char* getDefaultStr() const;
virtual char* getValueStr() const;
virtual bool isBool() const;
operator bool() const;
protected:
bool value;
bool def_value;
};
class PresetParameter : public BoolParameter {
public:
PresetParameter(const char* name_, const char* desc_, bool v,
void (*onSet)(void),
ConfigurationObject co=ConfGlobal);
virtual bool setParam(const char* value);
virtual bool setParam();
virtual void setParam(bool b);
protected:
void (*onSetCB)(void);
};
class IntParameter : public VoidParameter {
public:
IntParameter(const char* name_, const char* desc_, int v,
int minValue=INT_MIN, int maxValue=INT_MAX,
ConfigurationObject co=ConfGlobal);
using VoidParameter::setParam;
virtual bool setParam(const char* value);
virtual bool setParam(int v);
virtual char* getDefaultStr() const;
virtual char* getValueStr() const;
operator int() const;
protected:
int value;
int def_value;
int minValue, maxValue;
};
class StringParameter : public VoidParameter {
public:
// StringParameter contains a null-terminated string, which CANNOT
// be Null, and so neither can the default value!
StringParameter(const char* name_, const char* desc_, const char* v,
ConfigurationObject co=ConfGlobal);
virtual ~StringParameter();
virtual bool setParam(const char* value);
virtual char* getDefaultStr() const;
virtual char* getValueStr() const;
void setDefaultStr(const char* v);
operator const char*() const;
// getData() returns a copy of the data - it must be delete[]d by the
// caller.
char* getData() const { return getValueStr(); }
protected:
char* value;
const char* def_value;
};
class BinaryParameter : public VoidParameter {
public:
BinaryParameter(const char* name_, const char* desc_,
const void* v, size_t l,
ConfigurationObject co=ConfGlobal);
using VoidParameter::setParam;
virtual ~BinaryParameter();
virtual bool setParam(const char* value);
virtual void setParam(const void* v, size_t l);
virtual char* getDefaultStr() const;
virtual char* getValueStr() const;
// getData() will return length zero if there is no data
// NB: data may be set to zero, OR set to a zero-length buffer
void getData(void** data, size_t* length) const;
protected:
char* value;
size_t length;
char* def_value;
size_t def_length;
};
// -=- ParameterIterator
// Iterates over all enabled parameters (global + server/viewer).
// Current Parameter is accessed via param, the current Configuration
// via config. The next() method moves on to the next Parameter.
struct ParameterIterator {
ParameterIterator() : config(Configuration::global()), param(config->head) {}
void next() {
param = param->_next;
while (!param) {
config = config->_next;
if (!config) break;
param = config->head;
}
}
Configuration* config;
VoidParameter* param;
};
};
#endif // __RFB_CONFIGURATION_H__