| #region Copyright notice and license |
| // Protocol Buffers - Google's data interchange format |
| // Copyright 2008 Google Inc. All rights reserved. |
| // |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file or at |
| // https://developers.google.com/open-source/licenses/bsd |
| #endregion |
| |
| using System; |
| using System.Collections.Generic; |
| using System.Text; |
| |
| namespace Google.Protobuf.Reflection |
| { |
| /// <summary> |
| /// Contains lookup tables containing all the descriptors defined in a particular file. |
| /// </summary> |
| internal sealed class DescriptorPool |
| { |
| private readonly IDictionary<string, IDescriptor> descriptorsByName = |
| new Dictionary<string, IDescriptor>(); |
| |
| private readonly IDictionary<ObjectIntPair<IDescriptor>, FieldDescriptor> fieldsByNumber = |
| new Dictionary<ObjectIntPair<IDescriptor>, FieldDescriptor>(); |
| |
| private readonly IDictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor> enumValuesByNumber = |
| new Dictionary<ObjectIntPair<IDescriptor>, EnumValueDescriptor>(); |
| |
| private readonly IDictionary<EnumValueByNameDescriptorKey, EnumValueDescriptor> enumValuesByName = |
| new Dictionary<EnumValueByNameDescriptorKey, EnumValueDescriptor>(); |
| |
| private readonly HashSet<FileDescriptor> dependencies = new HashSet<FileDescriptor>(); |
| |
| internal DescriptorPool(IEnumerable<FileDescriptor> dependencyFiles) |
| { |
| foreach (FileDescriptor dependencyFile in dependencyFiles) |
| { |
| dependencies.Add(dependencyFile); |
| ImportPublicDependencies(dependencyFile); |
| } |
| |
| foreach (FileDescriptor dependency in dependencyFiles) |
| { |
| AddPackage(dependency.Package, dependency); |
| } |
| } |
| |
| private void ImportPublicDependencies(FileDescriptor file) |
| { |
| foreach (FileDescriptor dependency in file.PublicDependencies) |
| { |
| if (dependencies.Add(dependency)) |
| { |
| ImportPublicDependencies(dependency); |
| } |
| } |
| } |
| |
| /// <summary> |
| /// Finds a symbol of the given name within the pool. |
| /// </summary> |
| /// <typeparam name="T">The type of symbol to look for</typeparam> |
| /// <param name="fullName">Fully-qualified name to look up</param> |
| /// <returns>The symbol with the given name and type, |
| /// or null if the symbol doesn't exist or has the wrong type</returns> |
| internal T FindSymbol<T>(string fullName) where T : class |
| { |
| descriptorsByName.TryGetValue(fullName, out IDescriptor result); |
| if (result is T descriptor) |
| { |
| return descriptor; |
| } |
| |
| // dependencies contains direct dependencies and any *public* dependencies |
| // of those dependencies (transitively)... so we don't need to recurse here. |
| foreach (FileDescriptor dependency in dependencies) |
| { |
| dependency.DescriptorPool.descriptorsByName.TryGetValue(fullName, out result); |
| descriptor = result as T; |
| if (descriptor != null) |
| { |
| return descriptor; |
| } |
| } |
| |
| return null; |
| } |
| |
| /// <summary> |
| /// Adds a package to the symbol tables. If a package by the same name |
| /// already exists, that is fine, but if some other kind of symbol |
| /// exists under the same name, an exception is thrown. If the package |
| /// has multiple components, this also adds the parent package(s). |
| /// </summary> |
| internal void AddPackage(string fullName, FileDescriptor file) |
| { |
| int dotpos = fullName.LastIndexOf('.'); |
| String name; |
| if (dotpos != -1) |
| { |
| AddPackage(fullName.Substring(0, dotpos), file); |
| name = fullName.Substring(dotpos + 1); |
| } |
| else |
| { |
| name = fullName; |
| } |
| |
| if (descriptorsByName.TryGetValue(fullName, out IDescriptor old)) |
| { |
| if (old is not PackageDescriptor) |
| { |
| throw new DescriptorValidationException(file, |
| "\"" + name + |
| "\" is already defined (as something other than a " + |
| "package) in file \"" + old.File.Name + "\"."); |
| } |
| } |
| descriptorsByName[fullName] = new PackageDescriptor(name, fullName, file); |
| } |
| |
| /// <summary> |
| /// Adds a symbol to the symbol table. |
| /// </summary> |
| /// <exception cref="DescriptorValidationException">The symbol already existed |
| /// in the symbol table.</exception> |
| internal void AddSymbol(IDescriptor descriptor) |
| { |
| ValidateSymbolName(descriptor); |
| string fullName = descriptor.FullName; |
| |
| if (descriptorsByName.TryGetValue(fullName, out IDescriptor old)) |
| { |
| throw new DescriptorValidationException(descriptor, |
| GetDescriptorAlreadyAddedExceptionMessage(descriptor, fullName, old)); |
| } |
| descriptorsByName[fullName] = descriptor; |
| } |
| |
| private static string GetDescriptorAlreadyAddedExceptionMessage(IDescriptor descriptor, string fullName, IDescriptor old) |
| { |
| int dotPos = fullName.LastIndexOf('.'); |
| return descriptor.File != old.File ? $"\"{fullName}\" is already defined in file \"{old.File.Name}\"." |
| : dotPos == -1 ? $"{fullName} is already defined." |
| : $"\"{fullName.Substring(dotPos + 1)}\" is already defined in \"{fullName.Substring(0, dotPos)}\"."; |
| } |
| |
| /// <summary> |
| /// Verifies that the descriptor's name is valid (i.e. it contains |
| /// only letters, digits and underscores, and does not start with a digit). |
| /// </summary> |
| /// <param name="descriptor"></param> |
| private static void ValidateSymbolName(IDescriptor descriptor) |
| { |
| if (descriptor.Name.Length == 0) |
| { |
| throw new DescriptorValidationException(descriptor, "Missing name."); |
| } |
| |
| // Symbol name must start with a letter or underscore, and it can contain letters, |
| // numbers and underscores. |
| string name = descriptor.Name; |
| if (!IsAsciiLetter(name[0]) && name[0] != '_') |
| { |
| ThrowInvalidSymbolNameException(descriptor); |
| } |
| for (int i = 1; i < name.Length; i++) |
| { |
| if (!IsAsciiLetter(name[i]) && !IsAsciiDigit(name[i]) && name[i] != '_') |
| { |
| ThrowInvalidSymbolNameException(descriptor); |
| } |
| } |
| |
| static bool IsAsciiLetter(char c) => (uint)((c | 0x20) - 'a') <= 'z' - 'a'; |
| static bool IsAsciiDigit(char c) => (uint)(c - '0') <= '9' - '0'; |
| static void ThrowInvalidSymbolNameException(IDescriptor descriptor) => |
| throw new DescriptorValidationException( |
| descriptor, "\"" + descriptor.Name + "\" is not a valid identifier."); |
| } |
| |
| /// <summary> |
| /// Returns the field with the given number in the given descriptor, |
| /// or null if it can't be found. |
| /// </summary> |
| internal FieldDescriptor FindFieldByNumber(MessageDescriptor messageDescriptor, int number) |
| { |
| fieldsByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(messageDescriptor, number), out FieldDescriptor ret); |
| return ret; |
| } |
| |
| internal EnumValueDescriptor FindEnumValueByNumber(EnumDescriptor enumDescriptor, int number) |
| { |
| enumValuesByNumber.TryGetValue(new ObjectIntPair<IDescriptor>(enumDescriptor, number), out EnumValueDescriptor ret); |
| return ret; |
| } |
| |
| internal EnumValueDescriptor FindEnumValueByName(EnumDescriptor enumDescriptor, string name) |
| { |
| enumValuesByName.TryGetValue(new EnumValueByNameDescriptorKey(enumDescriptor, name), out EnumValueDescriptor ret); |
| return ret; |
| } |
| |
| /// <summary> |
| /// Adds a field to the fieldsByNumber table. |
| /// </summary> |
| /// <exception cref="DescriptorValidationException">A field with the same |
| /// containing type and number already exists.</exception> |
| internal void AddFieldByNumber(FieldDescriptor field) |
| { |
| // for extensions, we use the extended type, otherwise we use the containing type |
| ObjectIntPair<IDescriptor> key = new ObjectIntPair<IDescriptor>(field.Proto.HasExtendee ? field.ExtendeeType : field.ContainingType, field.FieldNumber); |
| if (fieldsByNumber.TryGetValue(key, out FieldDescriptor old)) |
| { |
| throw new DescriptorValidationException(field, "Field number " + field.FieldNumber + |
| "has already been used in \"" + |
| field.ContainingType.FullName + |
| "\" by field \"" + old.Name + "\"."); |
| } |
| fieldsByNumber[key] = field; |
| } |
| |
| /// <summary> |
| /// Adds an enum value to the enumValuesByNumber and enumValuesByName tables. If an enum value |
| /// with the same type and number already exists, this method does nothing to enumValuesByNumber. |
| /// (This is allowed; the first value defined with the number takes precedence.) If an enum |
| /// value with the same name already exists, this method throws DescriptorValidationException. |
| /// (It is expected that this method is called after AddSymbol, which would already have thrown |
| /// an exception in this failure case.) |
| /// </summary> |
| internal void AddEnumValue(EnumValueDescriptor enumValue) |
| { |
| ObjectIntPair<IDescriptor> numberKey = new ObjectIntPair<IDescriptor>(enumValue.EnumDescriptor, enumValue.Number); |
| if (!enumValuesByNumber.ContainsKey(numberKey)) |
| { |
| enumValuesByNumber[numberKey] = enumValue; |
| } |
| |
| EnumValueByNameDescriptorKey nameKey = new EnumValueByNameDescriptorKey(enumValue.EnumDescriptor, enumValue.Name); |
| if (enumValuesByName.TryGetValue(nameKey, out EnumValueDescriptor old)) |
| { |
| throw new DescriptorValidationException(enumValue, |
| GetDescriptorAlreadyAddedExceptionMessage(enumValue, enumValue.FullName, old)); |
| } |
| enumValuesByName[nameKey] = enumValue; |
| } |
| |
| /// <summary> |
| /// Looks up a descriptor by name, relative to some other descriptor. |
| /// The name may be fully-qualified (with a leading '.'), partially-qualified, |
| /// or unqualified. C++-like name lookup semantics are used to search for the |
| /// matching descriptor. |
| /// </summary> |
| /// <remarks> |
| /// This isn't heavily optimized, but it's only used during cross linking anyway. |
| /// If it starts being used more widely, we should look at performance more carefully. |
| /// </remarks> |
| internal IDescriptor LookupSymbol(string name, IDescriptor relativeTo) |
| { |
| IDescriptor result; |
| if (name.StartsWith(".")) |
| { |
| // Fully-qualified name. |
| result = FindSymbol<IDescriptor>(name.Substring(1)); |
| } |
| else |
| { |
| // If "name" is a compound identifier, we want to search for the |
| // first component of it, then search within it for the rest. |
| int firstPartLength = name.IndexOf('.'); |
| string firstPart = firstPartLength == -1 ? name : name.Substring(0, firstPartLength); |
| |
| // We will search each parent scope of "relativeTo" looking for the |
| // symbol. |
| StringBuilder scopeToTry = new StringBuilder(relativeTo.FullName); |
| |
| while (true) |
| { |
| // Chop off the last component of the scope. |
| |
| int dotpos = scopeToTry.ToString().LastIndexOf("."); |
| if (dotpos == -1) |
| { |
| result = FindSymbol<IDescriptor>(name); |
| break; |
| } |
| else |
| { |
| scopeToTry.Length = dotpos + 1; |
| |
| // Append firstPart and try to find. |
| scopeToTry.Append(firstPart); |
| result = FindSymbol<IDescriptor>(scopeToTry.ToString()); |
| |
| if (result != null) |
| { |
| if (firstPartLength != -1) |
| { |
| // We only found the first part of the symbol. Now look for |
| // the whole thing. If this fails, we *don't* want to keep |
| // searching parent scopes. |
| scopeToTry.Length = dotpos + 1; |
| scopeToTry.Append(name); |
| result = FindSymbol<IDescriptor>(scopeToTry.ToString()); |
| } |
| break; |
| } |
| |
| // Not found. Remove the name so we can try again. |
| scopeToTry.Length = dotpos; |
| } |
| } |
| } |
| |
| if (result == null) |
| { |
| throw new DescriptorValidationException(relativeTo, "\"" + name + "\" is not defined."); |
| } |
| else |
| { |
| return result; |
| } |
| } |
| |
| /// <summary> |
| /// Struct used to hold the keys for the enumValuesByName table. |
| /// </summary> |
| private struct EnumValueByNameDescriptorKey : IEquatable<EnumValueByNameDescriptorKey> |
| { |
| private readonly string name; |
| private readonly IDescriptor descriptor; |
| |
| internal EnumValueByNameDescriptorKey(EnumDescriptor descriptor, string valueName) |
| { |
| this.descriptor = descriptor; |
| this.name = valueName; |
| } |
| |
| public bool Equals(EnumValueByNameDescriptorKey other) => |
| descriptor == other.descriptor |
| && name == other.name; |
| |
| public override bool Equals(object obj) => |
| obj is EnumValueByNameDescriptorKey pair && Equals(pair); |
| |
| public override int GetHashCode() |
| { |
| unchecked |
| { |
| var hashCode = descriptor.GetHashCode(); |
| hashCode = (hashCode * 397) ^ (name != null ? name.GetHashCode() : 0); |
| return hashCode; |
| } |
| } |
| } |
| } |
| } |