Registry Component

The Registry library manages the collection of documentation sets (docsets), provides search functionality, and handles symbol indexing.

Registry::Docset

Represents a single documentation set with metadata, symbol index, and search capabilities. Location: src/libs/registry/docset.h

Docset Types

From src/libs/registry/docset.h:71-75:

enum class Type {
    Invalid,
    Dash,    // Dash-compatible docsets
    ZDash    // Zeal-specific format
};

Public Interface

class Docset final
{
public:
    explicit Docset(QString path);
    
    // Metadata
    bool isValid() const;
    QString name() const;
    QString title() const;
    QStringList keywords() const;
    QString version() const;
    int revision() const;
    QString feedUrl() const;
    QString path() const;
    QString documentPath() const;
    
    // Icon and visual
    QIcon icon() const;
    QIcon symbolTypeIcon(const QString &symbolType) const;
    QUrl indexFileUrl() const;
    
    // Symbol information
    QMap<QString, int> symbolCounts() const;
    int symbolCount(const QString &symbolType) const;
    const QMultiMap<QString, QUrl> &symbols(const QString &symbolType) const;
    
    // Search
    QList<SearchResult> search(const QString &query, 
                               const CancellationToken &token) const;
    QList<SearchResult> relatedLinks(const QUrl &url) const;
    QUrl searchResultUrl(const SearchResult &result) const;
    
    // Configuration
    QUrl baseUrl() const;
    void setBaseUrl(const QUrl &baseUrl);
    bool isFuzzySearchEnabled() const;
    void setFuzzySearchEnabled(bool enabled);
    bool isJavaScriptEnabled() const;
};

Internal Data

From src/libs/registry/docset.h:87-108:

QString m_name;
QString m_title;
QStringList m_keywords;
QString m_version;
int m_revision = 0;
QString m_feedUrl;
Docset::Type m_type = Type::Invalid;
QString m_path;
QIcon m_icon;

QUrl m_indexFileUrl;
QString m_indexFilePath;

QMultiMap<QString, QString> m_symbolStrings;
QMap<QString, int> m_symbolCounts;
mutable QMap<QString, QMultiMap<QString, QUrl>> m_symbols;
Util::SQLiteDatabase *m_db = nullptr;

bool m_isFuzzySearchEnabled = false;
bool m_isJavaScriptEnabled = false;

QUrl m_baseUrl;

Metadata Loading

Docsets use Dash-compatible format:

Info.plist: Property list with docset metadata
meta.json: Additional Zeal-specific metadata
icon.*: Docset icon in various formats

From src/libs/registry/docset.cpp:41-51, the Info.plist keys include:

CFBundleName            // Docset name
DashDocSetFamily        // Docset family
DashDocSetKeyword       // Search keyword
DashIndexFilePath       // Index page path
IsJavaScriptEnabled     // JavaScript support flag

SQLite Database Schema

Docsets use SQLite databases for symbol storage and search. The database typically contains:

searchIndex table: Main symbol index with name, type, and path columns
Custom indexes created by Zeal for performance optimization

Registry::DocsetRegistry

Manages the collection of all installed docsets. Location: src/libs/registry/docsetregistry.h

Interface

class DocsetRegistry final : public QObject
{
public:
    explicit DocsetRegistry(QObject *parent = nullptr);
    
    // Model for UI
    QAbstractItemModel *model() const;
    
    // Configuration
    QString storagePath() const;
    void setStoragePath(const QString &path);
    bool isFuzzySearchEnabled() const;
    void setFuzzySearchEnabled(bool enabled);
    
    // Collection management
    int count() const;
    bool contains(const QString &name) const;
    QStringList names() const;
    void loadDocset(const QString &path);
    void unloadDocset(const QString &name);
    void unloadAllDocsets();
    
    // Access
    Docset *docset(const QString &name) const;
    Docset *docset(int index) const;
    Docset *docsetForUrl(const QUrl &url);
    QList<Docset *> docsets() const;
    
    // Search
    void search(const QString &query);
    const QList<SearchResult> &queryResults();
    
signals:
    void docsetLoaded(const QString &name);
    void docsetAboutToBeUnloaded(const QString &name);
    void docsetUnloaded(const QString &name);
    void searchCompleted(const QList<SearchResult> &results);
};

Internal Structure

From src/libs/registry/docsetregistry.h:66-74:

QAbstractItemModel *m_model = nullptr;
QString m_storagePath;
bool m_isFuzzySearchEnabled = false;
QThread *m_thread = nullptr;
QMap<QString, Docset *> m_docsets;
CancellationToken m_cancellationToken;

Search Threading

Search operations can be performed asynchronously:

Uses a dedicated thread (m_thread) for intensive searches
CancellationToken allows canceling long-running searches
Results are emitted via searchCompleted signal

Registry::SearchQuery

Parses and represents search queries with optional docset filtering. Location: src/libs/registry/searchquery.h

Query Format

SearchQuery supports docset filtering using the : separator:

android:setTypeFa      → Search "setTypeFa" in Android docset
java,android:onCreate  → Search in Java AND Android docsets
std::string            → Search "std::string" (:: is preserved)
:find                  → Search ":find" literally

From src/libs/registry/searchquery.h:29-37:

// Examples:
//   "android:setTypeFa" → docsetFilters = ["android"], coreQuery = "setTypeFa"
//   "noprefix"          → docsetFilters = [], coreQuery = "noprefix"
//   ":find"             → docsetFilters = [], coreQuery = ":find"
//   "std::string"       → docsetFilters = [], coreQuery = "std::string"
//   "c++:std::string"   → docsetFilters = ["c++"], coreQuery = "std::string"
//   "java,android:..." → docsetFilters = ["java", "android"], coreQuery = "..."

Interface

class SearchQuery
{
public:
    explicit SearchQuery() = default;
    explicit SearchQuery(QString query, const QStringList &keywords = QStringList());
    
    static SearchQuery fromString(const QString &str);
    QString toString() const;
    bool isEmpty() const;
    
    QStringList keywords() const;
    void setKeywords(const QStringList &list);
    bool hasKeywords() const;
    bool hasKeywords(const QStringList &keywords) const;
    int keywordPrefixSize() const;
    
    QString query() const;
    void setQuery(const QString &str);
};

Registry::SearchResult

Represents a single search result with scoring and match positions. Location: src/libs/registry/searchresult.h

Structure

From src/libs/registry/searchresult.h:17-36:

struct SearchResult
{
    QString name;           // Symbol name
    QString type;           // Symbol type (class, function, etc.)
    
    QString urlPath;        // Documentation page path
    QString urlFragment;    // URL fragment/anchor
    
    Docset *docset;        // Parent docset
    
    double score;                    // Relevance score
    QVector<int> matchPositions;     // Character positions of matches
    
    // Sorting by score, then alphabetically
    inline bool operator<(const SearchResult &other) const
    {
        if (score == other.score)
            return QString::compare(name, other.name, Qt::CaseInsensitive) < 0;
        return score > other.score;
    }
};

Scoring Algorithm

Search results are scored based on:

Exact matches: Higher score
Prefix matches: Medium score
Fuzzy matches: Lower score with distance penalty
Position of matches: Earlier matches score higher

The Util::Fuzzy utility (from src/libs/util/fuzzy.h) implements fuzzy string matching with configurable algorithms.

Search Indexing

Index Creation

From src/libs/registry/docset.cpp:36-37, Zeal creates custom SQLite indexes:

constexpr char IndexNamePrefix[] = "__zi_name";  // zi - Zeal index
constexpr char IndexNameVersion[] = "0001";      // Current index version

Indexes are created on-demand during first search to optimize query performance.

SQLite Full-Text Search

Zeal uses SQLite’s FTS (Full-Text Search) capabilities:

Custom scoring function registered via sqlite3_create_function
View creation for optimized queries
Index management for fast symbol lookup

CancellationToken

Provides a mechanism to cancel long-running search operations. Location: src/libs/registry/cancellationtoken.h Used throughout search operations to check if the user has initiated a new search, allowing early termination of outdated searches.

Database Utilities

Util::SQLiteDatabase

Location: src/libs/util/sqlitedatabase.h Wrapper around SQLite C API providing:

Connection management
Query execution
Error handling
Resource cleanup

Symbol Types

Zeal supports various symbol types from Dash docsets:

Class/Type: Classes, interfaces, structs
Method/Function: Functions and methods
Property/Attribute: Properties and attributes
Constant: Constants and enums
Guide/Sample: Documentation pages and guides
Namespace/Module: Namespaces and modules

Each symbol type can have a custom icon defined in the docset.

Building

Architecture

Contributing

Registry Component

Registry::Docset

Docset Types

Public Interface

Internal Data

Metadata Loading

SQLite Database Schema

Registry::DocsetRegistry

Interface

Internal Structure

Search Threading

Registry::SearchQuery

Query Format

Interface

Registry::SearchResult

Structure

Scoring Algorithm

Search Indexing

Index Creation

SQLite Full-Text Search

CancellationToken

Database Utilities

Util::SQLiteDatabase

Symbol Types

See Also

Building

Architecture

Contributing

Documentation Index

​Registry::Docset

​Docset Types

​Public Interface

​Internal Data

​Metadata Loading

​SQLite Database Schema

​Registry::DocsetRegistry

​Interface

​Internal Structure

​Search Threading

​Registry::SearchQuery

​Query Format

​Interface

​Registry::SearchResult

​Structure

​Scoring Algorithm

​Search Indexing

​Index Creation

​SQLite Full-Text Search

​CancellationToken

​Database Utilities

​Util::SQLiteDatabase

​Symbol Types

​See Also

Registry::Docset

Docset Types

Public Interface

Internal Data

Metadata Loading

SQLite Database Schema

Registry::DocsetRegistry

Interface

Internal Structure

Search Threading

Registry::SearchQuery

Query Format

Interface

Registry::SearchResult

Structure

Scoring Algorithm

Search Indexing

Index Creation

SQLite Full-Text Search

CancellationToken

Database Utilities

Util::SQLiteDatabase

Symbol Types

See Also