OpenSimMirror/OpenSim/Region/ScriptEngine/YEngine/MMRScriptVarDict.cs

435 lines
16 KiB
C#

/*
* Copyright (c) Contributors, http://opensimulator.org/
* See CONTRIBUTORS.TXT for a full list of copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the OpenSimulator Project nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Collections;
using System.Collections.Generic;
/**
* @brief Collection of variable/function/method definitions
*/
namespace OpenSim.Region.ScriptEngine.Yengine
{
public class VarDict: IEnumerable
{
public VarDict outerVarDict; // next outer VarDict to search
public TokenDeclSDTypeClass thisClass; // this VarDict is for members of thisClass
private struct ArgTypes
{
public TokenType[] argTypes;
public bool CanBeCalledBy(TokenType[] calledBy)
{
if((argTypes == null) && (calledBy == null))
return true;
if((argTypes == null) || (calledBy == null))
return false;
if(argTypes.Length != calledBy.Length)
return false;
for(int i = argTypes.Length; --i >= 0;)
{
if(!TypeCast.IsAssignableFrom(argTypes[i], calledBy[i]))
return false;
}
return true;
}
public override bool Equals(Object that)
{
if(that == null)
return false;
if(that.GetType() != typeof(ArgTypes))
return false;
TokenType[] at = this.argTypes;
TokenType[] bt = ((ArgTypes)that).argTypes;
if((at == null) && (bt == null))
return true;
if((at == null) || (bt == null))
return false;
if(at.Length != bt.Length)
return false;
for(int i = at.Length; --i >= 0;)
{
if(at[i].ToString() != bt[i].ToString())
return false;
}
return true;
}
public override int GetHashCode()
{
TokenType[] at = this.argTypes;
if(at == null)
return -1;
int hc = 0;
for(int i = at.Length; --i >= 0;)
{
int c = (hc < 0) ? 1 : 0;
hc = hc * 2 + c;
hc ^= at[i].ToString().GetHashCode();
}
return hc;
}
}
private struct TDVEntry
{
public int count;
public TokenDeclVar var;
}
private bool isFrozen = false;
private bool locals;
private Dictionary<string, Dictionary<ArgTypes, TDVEntry>> master = new Dictionary<string, Dictionary<ArgTypes, TDVEntry>>();
private int count = 0;
private VarDict frozenLocals = null;
/**
* @brief Constructor.
* @param locals = false: cannot be frozen, allows forward references
* true: can be frozen, thus forbidding forward references
*/
public VarDict(bool locals)
{
this.locals = locals;
}
/**
* @brief Add new variable to the dictionary.
*/
public bool AddEntry(TokenDeclVar var)
{
if(isFrozen)
{
throw new Exception("var dict is frozen");
}
/*
* Make sure we have a sub-dictionary based on the bare name (ie, no signature)
*/
Dictionary<ArgTypes, TDVEntry> typedic;
if(!master.TryGetValue(var.name.val, out typedic))
{
typedic = new Dictionary<ArgTypes, TDVEntry>();
master.Add(var.name.val, typedic);
}
/*
* See if there is an entry in the sub-dictionary that matches the argument signature.
* Note that fields have null argument lists.
* Methods always have a non-null argument list, even if only 0 entries long.
*/
ArgTypes types;
types.argTypes = (var.argDecl == null) ? null : KeyTypesToStringTypes(var.argDecl.types);
if(typedic.ContainsKey(types))
return false;
/*
* It is unique, add to its name-specific sub-dictionary.
*/
TDVEntry entry;
entry.count = ++count;
entry.var = var;
typedic.Add(types, entry);
return true;
}
public int Count
{
get
{
return count;
}
}
/**
* @brief If this is not a local variable frame, just return the frame as is.
* If this is a local variable frame, return a version that is frozen,
* ie, one that does not contain any future additions.
*/
public VarDict FreezeLocals()
{
/*
* If not local var frame, return original frame as is.
* This will allow forward references as the future additions
* will be seen by lookups done in this dictionary.
*/
if(!locals)
return this;
/*
* If local var frame, return a copy frozen at this point.
* This disallows forward referenes as those future additions
* will not be seen by lookups done in the frozen dictionary.
*/
if((frozenLocals == null) || (frozenLocals.count != this.count))
{
/*
* Make a copy of the current var dictionary frame.
* We copy a reference to the dictionary, and though it may
* contain additions made after this point, those additions
* will have a count .gt. frozen count and will be ignored.
*/
frozenLocals = new VarDict(true);
frozenLocals.outerVarDict = this.outerVarDict;
frozenLocals.thisClass = this.thisClass;
frozenLocals.master = this.master;
frozenLocals.count = this.count;
frozenLocals.frozenLocals = frozenLocals;
/*
* Mark it as being frozen.
* - assert fail if any attempt is made to add to it
* - ignore any additions to the dictionary with greater count
*/
frozenLocals.isFrozen = true;
}
return frozenLocals;
}
/**
* @brief Find all functions/variables that are callable
* @param name = name of function/variable to look for
* @param argTypes = the argument types the function is being called with
* null to look for a variable
* @returns null: no matching function/variable found
* else: list of matching functions/variables
* for variables, always of length 1
*/
private List<TokenDeclVar> found = new List<TokenDeclVar>();
public TokenDeclVar[] FindCallables(string name, TokenType[] argTypes)
{
argTypes = KeyTypesToStringTypes(argTypes);
TokenDeclVar var = FindExact(name, argTypes);
if(var != null)
return new TokenDeclVar[] { var };
Dictionary<ArgTypes, TDVEntry> typedic;
if(!master.TryGetValue(name, out typedic))
return null;
found.Clear();
foreach(KeyValuePair<ArgTypes, TDVEntry> kvp in typedic)
{
if((kvp.Value.count <= this.count) && kvp.Key.CanBeCalledBy(argTypes))
{
found.Add(kvp.Value.var);
}
}
return (found.Count > 0) ? found.ToArray() : null;
}
/**
* @brief Find exact matching function/variable
* @param name = name of function to look for
* @param argTypes = argument types the function was declared with
* null to look for a variable
* @returns null: no matching function/variable found
* else: the matching function/variable
*/
public TokenDeclVar FindExact(string name, TokenType[] argTypes)
{
/*
* Look for list of stuff that matches the given name.
*/
Dictionary<ArgTypes, TDVEntry> typedic;
if(!master.TryGetValue(name, out typedic))
return null;
/*
* Loop through all fields/methods declared by that name, regardless of arg signature.
*/
foreach(TDVEntry entry in typedic.Values)
{
if(entry.count > this.count)
continue;
TokenDeclVar var = entry.var;
/*
* Get argument types of declaration.
* fields are always null
* methods are always non-null, though may be zero-length
*/
TokenType[] declArgs = (var.argDecl == null) ? null : var.argDecl.types;
/*
* Convert any key args to string args.
*/
declArgs = KeyTypesToStringTypes(declArgs);
/*
* If both are null, they are signature-less (ie, both are fields), and so match.
*/
if((declArgs == null) && (argTypes == null))
return var;
/*
* If calling a delegate, it is a match, regardless of delegate arg types.
* If it turns out the arg types do not match, the compiler will give an error
* trying to cast the arguments to the delegate arg types.
* We don't allow overloading same field name with different delegate types.
*/
if((declArgs == null) && (argTypes != null))
{
TokenType fieldType = var.type;
if(fieldType is TokenTypeSDTypeDelegate)
return var;
}
/*
* If not both null, no match, keep looking.
*/
if((declArgs == null) || (argTypes == null))
continue;
/*
* Both not null, match argument types to make sure we have correct overload.
*/
int i = declArgs.Length;
if(i != argTypes.Length)
continue;
while(--i >= 0)
{
string da = declArgs[i].ToString();
string ga = argTypes[i].ToString();
if(da == "key")
da = "string";
if(ga == "key")
ga = "string";
if(da != ga)
break;
}
if(i < 0)
return var;
}
/*
* No match.
*/
return null;
}
/**
* @brief Replace any TokenTypeKey elements with TokenTypeStr so that
* it doesn't matter if functions are declared with key or string,
* they will accept either.
* @param argTypes = argument types as declared in source code
* @returns argTypes with any key replaced by string
*/
private static TokenType[] KeyTypesToStringTypes(TokenType[] argTypes)
{
if(argTypes != null)
{
int i;
int nats = argTypes.Length;
for(i = nats; --i >= 0;)
{
if(argTypes[i] is TokenTypeKey)
break;
}
if(i >= 0)
{
TokenType[] at = new TokenType[nats];
for(i = nats; --i >= 0;)
{
at[i] = argTypes[i];
if(argTypes[i] is TokenTypeKey)
{
at[i] = new TokenTypeStr(argTypes[i]);
}
}
return at;
}
}
return argTypes;
}
// foreach goes through all the TokenDeclVars that were added
// IEnumerable
public IEnumerator GetEnumerator()
{
return new VarDictEnumerator(this.master, this.count);
}
private class VarDictEnumerator: IEnumerator
{
private IEnumerator masterEnum;
private IEnumerator typedicEnum;
private int count;
public VarDictEnumerator(Dictionary<string, Dictionary<ArgTypes, TDVEntry>> master, int count)
{
masterEnum = master.Values.GetEnumerator();
this.count = count;
}
// IEnumerator
public void Reset()
{
masterEnum.Reset();
typedicEnum = null;
}
// IEnumerator
public bool MoveNext()
{
while(true)
{
if(typedicEnum != null)
{
while(typedicEnum.MoveNext())
{
if(((TDVEntry)typedicEnum.Current).count <= this.count)
return true;
}
typedicEnum = null;
}
if(!masterEnum.MoveNext())
return false;
Dictionary<ArgTypes, TDVEntry> ctd;
ctd = (Dictionary<ArgTypes, TDVEntry>)masterEnum.Current;
typedicEnum = ctd.Values.GetEnumerator();
}
}
// IEnumerator
public object Current
{
get
{
return ((TDVEntry)typedicEnum.Current).var;
}
}
}
}
}