diff options
Diffstat (limited to '')
-rw-r--r-- | src/core/file_sys/vfs_concat.h | 40 |
1 files changed, 36 insertions, 4 deletions
diff --git a/src/core/file_sys/vfs_concat.h b/src/core/file_sys/vfs_concat.h index 717d04bdc..76211d38a 100644 --- a/src/core/file_sys/vfs_concat.h +++ b/src/core/file_sys/vfs_concat.h @@ -4,22 +4,25 @@ #pragma once +#include <map> #include <memory> #include <string_view> #include <boost/container/flat_map.hpp> #include "core/file_sys/vfs.h" +#include "core/file_sys/vfs_static.h" namespace FileSys { -// Wrapper function to allow for more efficient handling of files.size() == 0, 1 cases. -VirtualFile ConcatenateFiles(std::vector<VirtualFile> files, std::string name = ""); - // Class that wraps multiple vfs files and concatenates them, making reads seamless. Currently // read-only. class ConcatenatedVfsFile : public VfsFile { friend VirtualFile ConcatenateFiles(std::vector<VirtualFile> files, std::string name); + template <u8 filler_byte> + friend VirtualFile ConcatenateFiles(std::map<u64, VirtualFile> files, std::string name); + ConcatenatedVfsFile(std::vector<VirtualFile> files, std::string name); + ConcatenatedVfsFile(std::map<u64, VirtualFile> files, std::string name); public: ~ConcatenatedVfsFile() override; @@ -36,8 +39,37 @@ public: private: // Maps starting offset to file -- more efficient. - boost::container::flat_map<u64, VirtualFile> files; + std::map<u64, VirtualFile> files; std::string name; }; +// Wrapper function to allow for more efficient handling of files.size() == 0, 1 cases. +VirtualFile ConcatenateFiles(std::vector<VirtualFile> files, std::string name); + +// Convenience function that turns a map of offsets to files into a concatenated file, filling gaps +// with template parameter. +template <u8 filler_byte> +VirtualFile ConcatenateFiles(std::map<u64, VirtualFile> files, std::string name) { + if (files.empty()) + return nullptr; + if (files.size() == 1) + return files.begin()->second; + + const auto last_valid = --files.end(); + for (auto iter = files.begin(); iter != last_valid;) { + const auto old = iter++; + if (old->first + old->second->GetSize() != iter->first) { + files.emplace(old->first + old->second->GetSize(), + std::make_shared<StaticVfsFile<filler_byte>>(iter->first - old->first - + old->second->GetSize())); + } + } + + // Ensure the map starts at offset 0 (start of file), otherwise pad to fill. + if (files.begin()->first != 0) + files.emplace(0, std::make_shared<StaticVfsFile<filler_byte>>(files.begin()->first)); + + return std::shared_ptr<VfsFile>(new ConcatenatedVfsFile(std::move(files), std::move(name))); +} + } // namespace FileSys |