setBusyTimeout() now uses check() and throw in case of error

- add unit test for setBusyTimeout()
 - add unit test for in memory databases

include/SQLiteCpp/Database.h

@@ -59,7 +59,7 @@ public:
      *
      * @throw SQLite::Exception in case of error
      */
-    Database(const char* apFilename, const int aFlags = SQLITE_OPEN_READONLY, const char * apVfs = NULL);
+    Database(const char* apFilename, const int aFlags = SQLITE_OPEN_READONLY, const char* apVfs = NULL);
 
     /**
      * @brief Open the provided database UTF-8 filename.
@@ -89,6 +89,21 @@ public:
      */
     virtual ~Database() noexcept; // nothrow
 
+    /**
+     * @brief Set a busy handler that sleeps for a specified amount of time when a table is locked.
+     *
+     *  This is usefull in multithreaded program to handle case where a table is locked for writting by a thread.
+     * Any other thread cannot access the table and will receive a SQLITE_BUSY error:
+     * setting a timeout will wait and retry up to the time specified before returning this SQLITE_BUSY error.
+     *  Reading the value of timeout for current connection can be done with SQL query "PRAGMA busy_timeout;".
+     *  Default busy timeout is 0ms.
+     *
+     * @param[in] aTimeoutMs    Amount of milliseconds to wait before returning SQLITE_BUSY
+     *
+     * @throw SQLite::Exception in case of error
+     */
+    void setBusyTimeout(int aTimeoutMs) noexcept; // nothrow
+
     /**
      * @brief Shortcut to execute one or multiple statements without results.
      *
@@ -206,16 +221,6 @@ public:
         return tableExists(aTableName.c_str());
     }
 
-    /**
-     * @brief Set a busy handler that sleeps for a specified amount of time when a table is locked.
-     *
-     * @param[in] aTimeoutMs    Amount of milliseconds to wait before returning SQLITE_BUSY
-     */
-    inline int setBusyTimeout(int aTimeoutMs) noexcept // nothrow
-    {
-        return sqlite3_busy_timeout(mpSQLite, aTimeoutMs);
-    }
-
     /**
      * @brief Get the rowid of the most recent successful INSERT into the database from the current connection.
      *

src/Database.cpp

@@ -30,7 +30,7 @@ Database::Database(const char* apFilename, const int aFlags /*= SQLITE_OPEN_READ
     mpSQLite(NULL),
     mFilename(apFilename)
 {
-    int ret = sqlite3_open_v2(apFilename, &mpSQLite, aFlags, apVfs);
+    const int ret = sqlite3_open_v2(apFilename, &mpSQLite, aFlags, apVfs);
     if (SQLITE_OK != ret)
     {
         std::string strerr = sqlite3_errmsg(mpSQLite);
@@ -44,7 +44,7 @@ Database::Database(const std::string& aFilename, const int aFlags /*= SQLITE_OPE
     mpSQLite(NULL),
     mFilename(aFilename)
 {
-    int ret = sqlite3_open_v2(aFilename.c_str(), &mpSQLite, aFlags, aVfs.empty() ? NULL : aVfs.c_str());
+    const int ret = sqlite3_open_v2(aFilename.c_str(), &mpSQLite, aFlags, aVfs.empty() ? NULL : aVfs.c_str());
     if (SQLITE_OK != ret)
     {
         std::string strerr = sqlite3_errmsg(mpSQLite);
@@ -56,15 +56,34 @@ Database::Database(const std::string& aFilename, const int aFlags /*= SQLITE_OPE
 // Close the SQLite database connection.
 Database::~Database() noexcept // nothrow
 {
-    int ret = sqlite3_close(mpSQLite);
+    const int ret = sqlite3_close(mpSQLite);
     // Never throw an exception in a destructor
     SQLITECPP_ASSERT(SQLITE_OK == ret, sqlite3_errmsg(mpSQLite));  // See SQLITECPP_ENABLE_ASSERT_HANDLER
 }
 
+/**
+ * @brief Set a busy handler that sleeps for a specified amount of time when a table is locked.
+ *
+ *  This is usefull in multithreaded program to handle case where a table is locked for writting by a thread.
+ * Any other thread cannot access the table and will receive a SQLITE_BUSY error:
+ * setting a timeout will wait and retry up to the time specified before returning this SQLITE_BUSY error.
+ *  Reading the value of timeout for current connection can be done with SQL query "PRAGMA busy_timeout;".
+ *  Default busy timeout is 0ms.
+ *
+ * @param[in] aTimeoutMs    Amount of milliseconds to wait before returning SQLITE_BUSY
+ *
+ * @throw SQLite::Exception in case of error
+ */
+void Database::setBusyTimeout(int aTimeoutMs) noexcept // nothrow
+{
+    const int ret = sqlite3_busy_timeout(mpSQLite, aTimeoutMs);
+    check(ret);
+}
+
 // Shortcut to execute one or multiple SQL statements without results (UPDATE, INSERT, ALTER, COMMIT, CREATE...).
 int Database::exec(const char* apQueries)
 {
-    int ret = sqlite3_exec(mpSQLite, apQueries, NULL, NULL, NULL);
+    const int ret = sqlite3_exec(mpSQLite, apQueries, NULL, NULL, NULL);
     check(ret);
 
     // Return the number of rows modified by those SQL statements (INSERT, UPDATE or DELETE only)
@@ -90,7 +109,7 @@ bool Database::tableExists(const char* apTableName)
     Statement query(*this, "SELECT count(*) FROM sqlite_master WHERE type='table' AND name=?");
     query.bind(1, apTableName);
     (void)query.executeStep(); // Cannot return false, as the above query always return a result
-    int Nb = query.getColumn(0);
+    const int Nb = query.getColumn(0);
     return (1 == Nb);
 }
 
@@ -119,7 +138,7 @@ void Database::createFunction(const char*   apFuncName,
     if (abDeterministic) {
         TextRep = TextRep|SQLITE_DETERMINISTIC;
     }
-    int ret = sqlite3_create_function_v2(mpSQLite, apFuncName, aNbArg, TextRep,
+    const int ret = sqlite3_create_function_v2(mpSQLite, apFuncName, aNbArg, TextRep,
                                                apApp, apFunc, apStep, apFinal, apDestroy);
 
     check(ret);

tests/Database_test.cpp

@@ -54,11 +54,42 @@ TEST(Database, ctorExecCreateDropExist) {
     remove("test.db3");
 }
 
-TEST(Database, exec) {
+TEST(Database, inMemory) {
-    remove("test.db3");
     {
         // Create a new database
-        SQLite::Database db("test.db3", SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+        SQLite::Database db(":memory:", SQLITE_OPEN_READWRITE);
+        EXPECT_FALSE(db.tableExists("test"));
+        db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT)");
+        EXPECT_TRUE(db.tableExists("test"));
+        // Create a new database: not shared with the above db
+        SQLite::Database db2(":memory:");
+        EXPECT_FALSE(db2.tableExists("test"));
+    } // Close an destroy DBs
+    {
+        // Create a new database: no more "test" table
+        SQLite::Database db(":memory:");
+        EXPECT_FALSE(db.tableExists("test"));
+    } // Close an destroy DB
+}
+
+TEST(Database, busyTimeout) {
+    // Create a new database
+    SQLite::Database db(":memory:");
+    // Busy timeout default to 0ms: any contention between threads or process leads to SQLITE_BUSY error
+    EXPECT_EQ(0, db.execAndGet("PRAGMA busy_timeout").getInt());
+
+    // Set a non null busy timeout: any contention between threads will leads to as much retry as possible during the time
+    db.setBusyTimeout(5000);
+    EXPECT_EQ(5000, db.execAndGet("PRAGMA busy_timeout").getInt());
+
+    // Reset timeout to null
+    db.setBusyTimeout(0);
+    EXPECT_EQ(0, db.execAndGet("PRAGMA busy_timeout").getInt());
+}
+
+TEST(Database, exec) {
+    // Create a new database
+    SQLite::Database db(":memory:", SQLITE_OPEN_READWRITE);
 
     // Create a new table with an explicit "id" column aliasing the underlying rowid
     // NOTE: here exec() returns 0 only because it is the first statements since database connexion,
@@ -117,16 +148,11 @@ TEST(Database, exec) {
 
     // Add a row with too many values (more than rows in the table)
     EXPECT_THROW(db.exec("INSERT INTO test VALUES (NULL, \"first\", 123, 0.123)"), SQLite::Exception);
-
-    } // Close DB test.db3
-    remove("test.db3");
 }
 
 TEST(Database, execAndGet) {
-    remove("test.db3");
-    {
     // Create a new database
-        SQLite::Database db("test.db3", SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+    SQLite::Database db(":memory:", SQLITE_OPEN_READWRITE);
 
     // Create a new table with an explicit "id" column aliasing the underlying rowid
     db.exec("CREATE TABLE test (id INTEGER PRIMARY KEY, value TEXT, weight INTEGER)");
@@ -139,16 +165,12 @@ TEST(Database, execAndGet) {
     // Get a single value result with an easy to use shortcut
     EXPECT_STREQ("second",  db.execAndGet("SELECT value FROM test WHERE id=2"));
     EXPECT_STREQ("third",   db.execAndGet("SELECT value FROM test WHERE weight=7"));
-        EXPECT_EQ(3,       (int)db.execAndGet("SELECT weight FROM test WHERE value=\"first\""));
+    EXPECT_EQ(3,            db.execAndGet("SELECT weight FROM test WHERE value=\"first\"").getInt());
-    } // Close DB test.db3
-    remove("test.db3");
 }
 
 TEST(Database, execException) {
-    remove("test.db3");
-    {
     // Create a new database
-        SQLite::Database db("test.db3", SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
+    SQLite::Database db(":memory:", SQLITE_OPEN_READWRITE);
     EXPECT_EQ(SQLITE_OK, db.getErrorCode());
     EXPECT_EQ(SQLITE_OK, db.getExtendedErrorCode());
 
@@ -173,6 +195,4 @@ TEST(Database, execException) {
     EXPECT_EQ(1, db.exec("INSERT INTO test VALUES (NULL, \"first\",  3)"));
     // exception with SQL error: "No row to get a column from"
     EXPECT_THROW(db.execAndGet("SELECT weight FROM test WHERE value=\"second\""), SQLite::Exception);
-    } // Close DB test.db3
-    remove("test.db3");
 }