0ad/source/lib/res/file/zip.h

// archive backend for Zip files
//
// Copyright (c) 2003-2006 Jan Wassenberg
//
// This program 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 program 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.
//
// Contact info:
//   Jan.Wassenberg@stud.uni-karlsruhe.de
//   http://www.stud.uni-karlsruhe.de/~urkt/

#ifndef ZIP_H__
#define ZIP_H__

struct File;
struct Archive;
struct ArchiveEntry;


// analyse an opened file: if it is a Zip archive, call back into
// archive.cpp to populate the Archive object with a list of the
// files it contains.
// returns ERR_OK on success, ERR_UNKNOWN_FORMAT if not a Zip archive
// (see below) or another negative LibError code.
//
// fairly slow - must read Central Directory from disk
// (size ~= 60 bytes*num_files); observed time ~= 80ms.
extern LibError zip_populate_archive(File* f, Archive* a);


// ensures <ent.ofs> points to the actual file contents; it is initially
// the offset of the LFH. we cannot use CDFH filename and extra field
// lengths to skip past LFH since that may not mirror CDFH (has happened).
//
// this is called at file-open time instead of while mounting to
// reduce seeks: since reading the file will typically follow, the
// block cache entirely absorbs the IO cost.
extern void zip_fixup_lfh(File* f, ArchiveEntry* ent);


//
// archive builder backend
//

struct ZipArchive;	// opaque

// create a new Zip archive
extern LibError zip_archive_create(const char* zip_filename, ZipArchive** pza);
extern LibError zip_archive_add_file(ZipArchive* za, const ArchiveEntry* ae, void* file_contents);
extern LibError zip_archive_finish(ZipArchive* za);


#endif	// #ifndef ZIP_H__