pioneer/src/FileSourceZip.cpp

// Copyright © 2008-2021 Pioneer Developers. See AUTHORS.txt for details
// Licensed under the terms of the GPL v3. See licenses/GPL-3.txt

#include "FileSourceZip.h"
#include "utils.h"
#include <algorithm>
#include <cstdio>
#include <cstdlib>

extern "C" {
#include "miniz/miniz.h"
}

namespace FileSystem {

	FileSourceZip::FileSourceZip(FileSourceFS &fs, const std::string &zipPath) :
		FileSource(zipPath),
		m_archive(0)
	{
		mz_zip_archive *zip = static_cast<mz_zip_archive *>(std::calloc(1, sizeof(mz_zip_archive)));
		FILE *file = fs.OpenReadStream(zipPath);
		if (!mz_zip_reader_init_file_stream(zip, file, 0)) {
			Output("FileSourceZip: unable to open '%s'\n", zipPath.c_str());
			std::free(zip);
			return;
		}

		mz_zip_archive_file_stat zipStat;

		Uint32 numFiles = mz_zip_reader_get_num_files(zip);
		for (Uint32 i = 0; i < numFiles; i++) {
			if (mz_zip_reader_file_stat(zip, i, &zipStat)) {
				bool is_dir = mz_zip_reader_is_file_a_directory(zip, i);
				if (!mz_zip_reader_is_file_encrypted(zip, i)) {
					std::string fname = zipStat.m_filename;
					if ((fname.size() > 1) && (fname[fname.size() - 1] == '/')) {
						fname.resize(fname.size() - 1);
					}
					AddFile(zipStat.m_filename, FileStat(i, zipStat.m_uncomp_size, MakeFileInfo(fname, is_dir ? FileInfo::FT_DIR : FileInfo::FT_FILE)));
				}
			}
		}

		m_archive = static_cast<void *>(zip);
	}

	FileSourceZip::~FileSourceZip()
	{
		if (!m_archive) return;
		mz_zip_archive *zip = static_cast<mz_zip_archive *>(m_archive);
		mz_zip_reader_end(zip);
	}

	static void SplitPath(const std::string &path, std::vector<std::string> &output)
	{
		static const std::string delim("/");

		size_t start = 0, end = 0;
		while (end != std::string::npos) {
			// get to the first non-delim char
			start = path.find_first_not_of(delim, end);

			// read the end, no more to do
			if (start == std::string::npos)
				break;

			// find the end - next delim or end of string
			end = path.find_first_of(delim, start);

			// extract the fragment and remember it
			output.push_back(path.substr(start, (end == std::string::npos) ? std::string::npos : end - start));
		}
	}

	bool FileSourceZip::FindDirectoryAndFile(const std::string &path, const Directory *&dir, std::string &filename)
	{
		std::vector<std::string> fragments;
		SplitPath(NormalisePath(path), fragments);

		assert(fragments.size() > 0);

		dir = &m_root;

		if (fragments.size() > 1) {
			for (unsigned int i = 0; i < fragments.size() - 1; i++) {
				std::map<std::string, Directory>::const_iterator it = dir->subdirs.find(fragments[i]);
				if (it == dir->subdirs.end())
					return false;
				dir = &((*it).second);
			}
		}

		filename = fragments.back();
		return true;
	}

	FileInfo FileSourceZip::Lookup(const std::string &path)
	{
		const Directory *dir;
		std::string filename;
		if (!FindDirectoryAndFile(path, dir, filename))
			return MakeFileInfo(path, FileInfo::FT_NON_EXISTENT);

		std::map<std::string, FileStat>::const_iterator i = dir->files.find(filename);
		if (i == dir->files.end())
			return MakeFileInfo(path, FileInfo::FT_NON_EXISTENT);

		return (*i).second.info;
	}

	RefCountedPtr<FileData> FileSourceZip::ReadFile(const std::string &path)
	{
		if (!m_archive) return RefCountedPtr<FileData>();
		mz_zip_archive *zip = static_cast<mz_zip_archive *>(m_archive);

		const Directory *dir;
		std::string filename;
		if (!FindDirectoryAndFile(path, dir, filename))
			return RefCountedPtr<FileData>();

		std::map<std::string, FileStat>::const_iterator i = dir->files.find(filename);
		if (i == dir->files.end())
			return RefCountedPtr<FileData>();

		const FileStat &st = (*i).second;

		char *data = static_cast<char *>(std::malloc(st.size));
		if (!mz_zip_reader_extract_to_mem(zip, st.index, data, st.size, 0)) {
			Output("FileSourceZip::ReadFile: couldn't extract '%s'\n", path.c_str());
			return RefCountedPtr<FileData>();
		}

		return RefCountedPtr<FileData>(new FileDataMalloc(st.info, st.size, data));
	}

	bool FileSourceZip::ReadDirectory(const std::string &path, std::vector<FileInfo> &output)
	{
		const Directory *dir;
		std::string filename;
		if (!FindDirectoryAndFile(path, dir, filename))
			return false;

		{
			std::map<std::string, Directory>::const_iterator i = dir->subdirs.find(filename);
			if (i == dir->subdirs.end())
				return false;
			dir = &((*i).second);
		}

		for (std::map<std::string, FileStat>::const_iterator i = dir->files.begin(); i != dir->files.end(); ++i)
			output.push_back((*i).second.info);

		return true;
	}

	void FileSourceZip::AddFile(const std::string &path, const FileStat &fileStat)
	{
		std::vector<std::string> fragments;
		SplitPath(path, fragments);

		assert(fragments.size() > 0);

		Directory *dir = &m_root;

		if (fragments.size() > 1) {
			std::string fullPath;

			for (unsigned int i = 0; i < fragments.size() - 1; i++) {
				fullPath += ((i > 0) ? "/" : "") + fragments[i];

				std::map<std::string, FileStat>::const_iterator it = dir->files.find(fragments[i]);
				if (it == dir->files.end())
					dir->files.insert(std::make_pair(fragments[i], FileStat(Uint32(-1), 0, MakeFileInfo(fullPath, FileInfo::FT_DIR))));
				dir = &(dir->subdirs[fragments[i]]);
			}
		}

		const std::string &filename = fragments.back();

		if (fileStat.info.IsDir())
			dir->subdirs.insert(std::make_pair(filename, Directory()));

		dir->files.insert(std::make_pair(filename, fileStat));
	}

} // namespace FileSystem