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Diffstat (limited to 'src/google/protobuf/compiler/importer.h')
| -rw-r--r-- | src/google/protobuf/compiler/importer.h | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/src/google/protobuf/compiler/importer.h b/src/google/protobuf/compiler/importer.h new file mode 100644 index 00000000..cc8fcc39 --- /dev/null +++ b/src/google/protobuf/compiler/importer.h @@ -0,0 +1,326 @@ +// Protocol Buffers - Google's data interchange format +// Copyright 2008 Google Inc. All rights reserved. +// https://developers.google.com/protocol-buffers/ +// +// 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 Google Inc. 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 COPYRIGHT HOLDERS AND CONTRIBUTORS +// "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 COPYRIGHT +// OWNER OR 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. + +// Author: kenton@google.com (Kenton Varda) +// Based on original Protocol Buffers design by +// Sanjay Ghemawat, Jeff Dean, and others. +// +// This file is the public interface to the .proto file parser. + +#ifndef GOOGLE_PROTOBUF_COMPILER_IMPORTER_H__ +#define GOOGLE_PROTOBUF_COMPILER_IMPORTER_H__ + +#include <string> +#include <vector> +#include <set> +#include <utility> +#include <google/protobuf/descriptor.h> +#include <google/protobuf/descriptor_database.h> +#include <google/protobuf/compiler/parser.h> + +namespace google { +namespace protobuf { + +namespace io { class ZeroCopyInputStream; } + +namespace compiler { + +// Defined in this file. +class Importer; +class MultiFileErrorCollector; +class SourceTree; +class DiskSourceTree; + +// TODO(kenton): Move all SourceTree stuff to a separate file? + +// An implementation of DescriptorDatabase which loads files from a SourceTree +// and parses them. +// +// Note: This class is not thread-safe since it maintains a table of source +// code locations for error reporting. However, when a DescriptorPool wraps +// a DescriptorDatabase, it uses mutex locking to make sure only one method +// of the database is called at a time, even if the DescriptorPool is used +// from multiple threads. Therefore, there is only a problem if you create +// multiple DescriptorPools wrapping the same SourceTreeDescriptorDatabase +// and use them from multiple threads. +// +// Note: This class does not implement FindFileContainingSymbol() or +// FindFileContainingExtension(); these will always return false. +class LIBPROTOBUF_EXPORT SourceTreeDescriptorDatabase : public DescriptorDatabase { + public: + SourceTreeDescriptorDatabase(SourceTree* source_tree); + ~SourceTreeDescriptorDatabase(); + + // Instructs the SourceTreeDescriptorDatabase to report any parse errors + // to the given MultiFileErrorCollector. This should be called before + // parsing. error_collector must remain valid until either this method + // is called again or the SourceTreeDescriptorDatabase is destroyed. + void RecordErrorsTo(MultiFileErrorCollector* error_collector) { + error_collector_ = error_collector; + } + + // Gets a DescriptorPool::ErrorCollector which records errors to the + // MultiFileErrorCollector specified with RecordErrorsTo(). This collector + // has the ability to determine exact line and column numbers of errors + // from the information given to it by the DescriptorPool. + DescriptorPool::ErrorCollector* GetValidationErrorCollector() { + using_validation_error_collector_ = true; + return &validation_error_collector_; + } + + // implements DescriptorDatabase ----------------------------------- + bool FindFileByName(const string& filename, FileDescriptorProto* output); + bool FindFileContainingSymbol(const string& symbol_name, + FileDescriptorProto* output); + bool FindFileContainingExtension(const string& containing_type, + int field_number, + FileDescriptorProto* output); + + private: + class SingleFileErrorCollector; + + SourceTree* source_tree_; + MultiFileErrorCollector* error_collector_; + + class LIBPROTOBUF_EXPORT ValidationErrorCollector : public DescriptorPool::ErrorCollector { + public: + ValidationErrorCollector(SourceTreeDescriptorDatabase* owner); + ~ValidationErrorCollector(); + + // implements ErrorCollector --------------------------------------- + void AddError(const string& filename, + const string& element_name, + const Message* descriptor, + ErrorLocation location, + const string& message); + + virtual void AddWarning(const string& filename, + const string& element_name, + const Message* descriptor, + ErrorLocation location, + const string& message); + + private: + SourceTreeDescriptorDatabase* owner_; + }; + friend class ValidationErrorCollector; + + bool using_validation_error_collector_; + SourceLocationTable source_locations_; + ValidationErrorCollector validation_error_collector_; +}; + +// Simple interface for parsing .proto files. This wraps the process +// of opening the file, parsing it with a Parser, recursively parsing all its +// imports, and then cross-linking the results to produce a FileDescriptor. +// +// This is really just a thin wrapper around SourceTreeDescriptorDatabase. +// You may find that SourceTreeDescriptorDatabase is more flexible. +// +// TODO(kenton): I feel like this class is not well-named. +class LIBPROTOBUF_EXPORT Importer { + public: + Importer(SourceTree* source_tree, + MultiFileErrorCollector* error_collector); + ~Importer(); + + // Import the given file and build a FileDescriptor representing it. If + // the file is already in the DescriptorPool, the existing FileDescriptor + // will be returned. The FileDescriptor is property of the DescriptorPool, + // and will remain valid until it is destroyed. If any errors occur, they + // will be reported using the error collector and Import() will return NULL. + // + // A particular Importer object will only report errors for a particular + // file once. All future attempts to import the same file will return NULL + // without reporting any errors. The idea is that you might want to import + // a lot of files without seeing the same errors over and over again. If + // you want to see errors for the same files repeatedly, you can use a + // separate Importer object to import each one (but use the same + // DescriptorPool so that they can be cross-linked). + const FileDescriptor* Import(const string& filename); + + // The DescriptorPool in which all imported FileDescriptors and their + // contents are stored. + inline const DescriptorPool* pool() const { + return &pool_; + } + + void AddUnusedImportTrackFile(const string& file_name); + void ClearUnusedImportTrackFiles(); + + private: + SourceTreeDescriptorDatabase database_; + DescriptorPool pool_; + + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Importer); +}; + +// If the importer encounters problems while trying to import the proto files, +// it reports them to a MultiFileErrorCollector. +class LIBPROTOBUF_EXPORT MultiFileErrorCollector { + public: + inline MultiFileErrorCollector() {} + virtual ~MultiFileErrorCollector(); + + // Line and column numbers are zero-based. A line number of -1 indicates + // an error with the entire file (e.g. "not found"). + virtual void AddError(const string& filename, int line, int column, + const string& message) = 0; + + virtual void AddWarning(const string& filename, int line, int column, + const string& message) {} + + private: + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MultiFileErrorCollector); +}; + +// Abstract interface which represents a directory tree containing proto files. +// Used by the default implementation of Importer to resolve import statements +// Most users will probably want to use the DiskSourceTree implementation, +// below. +class LIBPROTOBUF_EXPORT SourceTree { + public: + inline SourceTree() {} + virtual ~SourceTree(); + + // Open the given file and return a stream that reads it, or NULL if not + // found. The caller takes ownership of the returned object. The filename + // must be a path relative to the root of the source tree and must not + // contain "." or ".." components. + virtual io::ZeroCopyInputStream* Open(const string& filename) = 0; + + // If Open() returns NULL, calling this method immediately will return an + // description of the error. + // Subclasses should implement this method and return a meaningful value for + // better error reporting. + // TODO(xiaofeng): change this to a pure virtual function. + virtual string GetLastErrorMessage(); + + private: + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(SourceTree); +}; + +// An implementation of SourceTree which loads files from locations on disk. +// Multiple mappings can be set up to map locations in the DiskSourceTree to +// locations in the physical filesystem. +class LIBPROTOBUF_EXPORT DiskSourceTree : public SourceTree { + public: + DiskSourceTree(); + ~DiskSourceTree(); + + // Map a path on disk to a location in the SourceTree. The path may be + // either a file or a directory. If it is a directory, the entire tree + // under it will be mapped to the given virtual location. To map a directory + // to the root of the source tree, pass an empty string for virtual_path. + // + // If multiple mapped paths apply when opening a file, they will be searched + // in order. For example, if you do: + // MapPath("bar", "foo/bar"); + // MapPath("", "baz"); + // and then you do: + // Open("bar/qux"); + // the DiskSourceTree will first try to open foo/bar/qux, then baz/bar/qux, + // returning the first one that opens successfuly. + // + // disk_path may be an absolute path or relative to the current directory, + // just like a path you'd pass to open(). + void MapPath(const string& virtual_path, const string& disk_path); + + // Return type for DiskFileToVirtualFile(). + enum DiskFileToVirtualFileResult { + SUCCESS, + SHADOWED, + CANNOT_OPEN, + NO_MAPPING + }; + + // Given a path to a file on disk, find a virtual path mapping to that + // file. The first mapping created with MapPath() whose disk_path contains + // the filename is used. However, that virtual path may not actually be + // usable to open the given file. Possible return values are: + // * SUCCESS: The mapping was found. *virtual_file is filled in so that + // calling Open(*virtual_file) will open the file named by disk_file. + // * SHADOWED: A mapping was found, but using Open() to open this virtual + // path will end up returning some different file. This is because some + // other mapping with a higher precedence also matches this virtual path + // and maps it to a different file that exists on disk. *virtual_file + // is filled in as it would be in the SUCCESS case. *shadowing_disk_file + // is filled in with the disk path of the file which would be opened if + // you were to call Open(*virtual_file). + // * CANNOT_OPEN: The mapping was found and was not shadowed, but the + // file specified cannot be opened. When this value is returned, + // errno will indicate the reason the file cannot be opened. *virtual_file + // will be set to the virtual path as in the SUCCESS case, even though + // it is not useful. + // * NO_MAPPING: Indicates that no mapping was found which contains this + // file. + DiskFileToVirtualFileResult + DiskFileToVirtualFile(const string& disk_file, + string* virtual_file, + string* shadowing_disk_file); + + // Given a virtual path, find the path to the file on disk. + // Return true and update disk_file with the on-disk path if the file exists. + // Return false and leave disk_file untouched if the file doesn't exist. + bool VirtualFileToDiskFile(const string& virtual_file, string* disk_file); + + // implements SourceTree ------------------------------------------- + virtual io::ZeroCopyInputStream* Open(const string& filename); + + virtual string GetLastErrorMessage(); + + private: + struct Mapping { + string virtual_path; + string disk_path; + + inline Mapping(const string& virtual_path_param, + const string& disk_path_param) + : virtual_path(virtual_path_param), disk_path(disk_path_param) {} + }; + vector<Mapping> mappings_; + string last_error_message_; + + // Like Open(), but returns the on-disk path in disk_file if disk_file is + // non-NULL and the file could be successfully opened. + io::ZeroCopyInputStream* OpenVirtualFile(const string& virtual_file, + string* disk_file); + + // Like Open() but given the actual on-disk path. + io::ZeroCopyInputStream* OpenDiskFile(const string& filename); + + GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(DiskSourceTree); +}; + +} // namespace compiler +} // namespace protobuf + +} // namespace google +#endif // GOOGLE_PROTOBUF_COMPILER_IMPORTER_H__ |