Class DirExtractSink

common/script/zip_api.cpp:94–144

Writes extracted entries under `root`, creating parent directories as it goes. mkdir on an existing path fails harmlessly; the fopen is the real success check.

    // goes. mkdir on an existing path fails harmlessly; the fopen is the real
    // success check.
    struct DirExtractSink : TransferProto::ExtractSink {
        std::string root; // always ends with '/'
        FILE* out = nullptr;
        explicit DirExtractSink(std::string r) : root(std::move(r))
        {
            if (root.empty() || root.back() != '/') {
                root += '/';
            }
        }
        ~DirExtractSink() override
        {
            if (out != nullptr) {
                fclose(out);
            }
        }
        void ensureParents(const std::string& relPath)
        {
            std::string current = root;
            size_t start        = 0;
            for (size_t pos = relPath.find('/', start); pos != std::string::npos; pos = relPath.find('/', start)) {
                current += relPath.substr(start, pos - start);
                mkdir(current.c_str(), 0777);
                current += '/';
                start = pos + 1;
            }
        }
        bool makeDir(const std::string& relPath) override
        {
            ensureParents(relPath);
            std::string full = root + relPath;
            if (!full.empty() && full.back() == '/') {
                full.pop_back();
            }
            mkdir(full.c_str(), 0777);
            return true;
        }
        bool beginFile(const std::string& relPath, uint32_t) override
        {
            ensureParents(relPath);
            out = fopen((root + relPath).c_str(), "wb");
            return out != nullptr;
        }
        bool writeFile(const void* data, size_t n) override { return out != nullptr && fwrite(data, 1, n, out) == n; }
        void endFile() override
        {
            if (out != nullptr) {
                fclose(out);
                out = nullptr;
            }
        }
    };

    // Recursively gather files (with '/'-separated relative paths) and the dir
    // list sendZipStream needs. Returns false if any regular file exceeds the