sysupdater: don't do unnecessary work when parsing update

This commit is contained in:
Michael Scire 2020-06-26 05:05:24 -07:00 committed by SciresM
parent 3324dd52ef
commit 1bc271bab1
3 changed files with 124 additions and 32 deletions

View file

@ -196,6 +196,19 @@ namespace ams::mitm::sysupdater {
}
bool PathView::HasPrefix(std::string_view prefix) const {
return this->path.compare(0, prefix.length(), prefix) == 0;
}
bool PathView::HasSuffix(std::string_view suffix) const {
return this->path.compare(this->path.length() - suffix.length(), suffix.length(), suffix) == 0;
}
std::string_view PathView::GetFileName() const {
auto pos = this->path.find_last_of("/");
return pos != std::string_view::npos ? this->path.substr(pos + 1) : this->path;
}
Result MountSdCardContentMeta(const char *mount_name, const char *path) {
/* Sanitize input. */
/* NOTE: This is an internal API, so we won't bother with mount name sanitization. */

View file

@ -18,6 +18,16 @@
namespace ams::mitm::sysupdater {
class PathView {
private:
std::string_view path; /* Nintendo uses util::string_view here. */
public:
PathView(std::string_view p) : path(p) { /* ...*/ }
bool HasPrefix(std::string_view prefix) const;
bool HasSuffix(std::string_view suffix) const;
std::string_view GetFileName() const;
};
Result MountSdCardContentMeta(const char *mount_name, const char *path);
}

View file

@ -15,6 +15,7 @@
*/
#include <stratosphere.hpp>
#include "sysupdater_service.hpp"
#include "sysupdater_fs_utils.hpp"
namespace ams::mitm::sysupdater {
@ -23,6 +24,104 @@ namespace ams::mitm::sysupdater {
/* ExFat NCAs prior to 2.0.0 do not actually include the exfat driver, and don't boot. */
constexpr inline u32 MinimumVersionForExFatDriver = 65536;
template<typename F>
Result ForEachFileInDirectory(const char *root_path, F f) {
/* Open the directory. */
fs::DirectoryHandle dir;
R_TRY(fs::OpenDirectory(std::addressof(dir), root_path, fs::OpenDirectoryMode_File));
ON_SCOPE_EXIT { fs::CloseDirectory(dir); };
while (true) {
/* Read the current entry. */
s64 count;
fs::DirectoryEntry entry;
R_TRY(fs::ReadDirectory(std::addressof(count), std::addressof(entry), dir, 1));
if (count == 0) {
break;
}
/* Invoke our handler on the entry. */
bool done;
R_TRY(f(std::addressof(done), entry));
R_SUCCEED_IF(done);
}
return ResultSuccess();
}
Result ConvertToFsCommonPath(char *dst, size_t dst_size, const char *package_root_path, const char *entry_path) {
char package_path[ams::fs::EntryNameLengthMax];
const size_t path_len = std::snprintf(package_path, sizeof(package_path), "%s%s", package_root_path, entry_path);
AMS_ABORT_UNLESS(path_len < ams::fs::EntryNameLengthMax);
return ams::fs::ConvertToFsCommonPath(dst, dst_size, package_path);
}
Result LoadContentMeta(ncm::AutoBuffer *out, const char *package_root_path, const fs::DirectoryEntry &entry) {
AMS_ABORT_UNLESS(PathView(entry.name).HasSuffix(".cnmt.nca"));
char path[ams::fs::EntryNameLengthMax];
R_TRY(ConvertToFsCommonPath(path, sizeof(path), package_root_path, entry.name));
return ncm::ReadContentMetaPath(out, path);
}
Result ReadContentMetaPath(ncm::AutoBuffer *out, const char *package_root, const ncm::ContentInfo &content_info) {
/* Get the .cnmt.nca path for the info. */
char cnmt_nca_name[ncm::ContentIdStringLength + 10];
ncm::GetStringFromContentId(cnmt_nca_name, sizeof(cnmt_nca_name), content_info.GetId());
std::memcpy(cnmt_nca_name + ncm::ContentIdStringLength, ".cnmt.nca", std::strlen(".cnmt.nca"));
cnmt_nca_name[sizeof(cnmt_nca_name) - 1] = '\x00';
/* Create a new path. */
ncm::Path content_path;
R_TRY(ConvertToFsCommonPath(content_path.str, sizeof(content_path.str), package_root, cnmt_nca_name));
/* Read the content meta path. */
return ncm::ReadContentMetaPath(out, content_path.str);
}
Result GetSystemUpdateUpdateContentInfoFromPackage(ncm::ContentInfo *out, const char *package_root) {
bool found_system_update = false;
/* Iterate over all files to find the system update meta. */
R_TRY(ForEachFileInDirectory(package_root, [&](bool *done, const fs::DirectoryEntry &entry) -> Result {
/* Don't early terminate by default. */
*done = false;
/* We have nothing to list if we're not looking at a meta. */
R_SUCCEED_IF(!PathView(entry.name).HasSuffix(".cnmt.nca"));
/* Read the content meta path, and build. */
ncm::AutoBuffer package_meta;
R_TRY(LoadContentMeta(std::addressof(package_meta), package_root, entry));
/* Create a reader. */
const auto reader = ncm::PackagedContentMetaReader(package_meta.Get(), package_meta.GetSize());
/* If we find a system update, we're potentially done. */
if (reader.GetHeader()->type == ncm::ContentMetaType::SystemUpdate) {
/* Try to parse a content id from the name. */
auto content_id = ncm::GetContentIdFromString(entry.name, sizeof(entry.name));
R_UNLESS(content_id, ncm::ResultInvalidPackageFormat());
/* We're done. */
*done = true;
found_system_update = true;
*out = ncm::ContentInfo::Make(*content_id, entry.file_size, ncm::ContentType::Meta);
}
return ResultSuccess();
}));
/* If we didn't find anything, error. */
R_UNLESS(found_system_update, ncm::ResultSystemUpdateNotFoundInPackage());
return ResultSuccess();
}
Result ActivateSystemUpdateContentMetaDatabase() {
/* TODO: Don't use gamecard db. */
return ncm::ActivateContentMetaDatabase(ncm::StorageId::GameCard);
@ -62,18 +161,6 @@ namespace ams::mitm::sysupdater {
return ncm::ResultContentInfoNotFound();
}
Result ReadContentMetaPath(ncm::AutoBuffer *out, const char *package_root, const ncm::ContentInfo &content_info) {
/* Get the content id string for the info. */
auto content_id_str = ncm::GetContentIdString(content_info.GetId());
/* Create a new path. */
ncm::Path content_path;
std::snprintf(content_path.str, sizeof(content_path.str), "%s/%s.cnmt.nca", package_root, content_id_str.data);
/* Read the content meta path. */
return ncm::ReadContentMetaPath(out, content_path.str);
}
bool IsExFatDriverSupported(const ncm::ContentMetaInfo &info) {
return info.version >= MinimumVersionForExFatDriver && ((info.attributes & ncm::ContentMetaAttribute_IncludesExFatDriver) != 0);
}
@ -106,27 +193,9 @@ namespace ams::mitm::sysupdater {
/* Parse the update. */
{
/* Activate the package database. */
R_TRY(ActivateSystemUpdateContentMetaDatabase());
ON_SCOPE_EXIT { InactivateSystemUpdateContentMetaDatabase(); };
/* Open the package database. */
ncm::ContentMetaDatabase package_db;
R_TRY(OpenSystemUpdateContentMetaDatabase(std::addressof(package_db)));
/* Cleanup and build the content meta database. */
ncm::ContentMetaDatabaseBuilder builder(std::addressof(package_db));
R_TRY(builder.Cleanup());
R_TRY(builder.BuildFromPackage(package_root.str));
/* Get the key for the SystemUpdate. */
ncm::ContentMetaKey key;
auto list_count = package_db.ListContentMeta(std::addressof(key), 1, ncm::ContentMetaType::SystemUpdate);
R_UNLESS(list_count.written > 0, ncm::ResultSystemUpdateNotFoundInPackage());
/* Get the content info for the key. */
/* Get the content info for the system update. */
ncm::ContentInfo content_info;
R_TRY(GetContentInfoOfContentMeta(std::addressof(content_info), package_db, key));
R_TRY(GetSystemUpdateUpdateContentInfoFromPackage(std::addressof(content_info), package_root.str));
/* Read the content meta. */
ncm::AutoBuffer content_meta_buffer;