Merge pull request #824 from gwenn/progress_handler

Expose query progress information

src/blob/mod.rs

@@ -136,7 +136,10 @@
 //!
 //! // Insert another BLOB, this time using a parameter passed in from
 //! // rust (potentially with a dynamic size).
-//! db.execute("INSERT INTO test_table (content) VALUES (?)", &[ZeroBlob(64)])?;
+//! db.execute(
+//!     "INSERT INTO test_table (content) VALUES (?)",
+//!     &[ZeroBlob(64)],
+//! )?;
 //!
 //! // given a new row ID, we can reopen the blob on that row
 //! let rowid = db.last_insert_rowid();
@@ -177,7 +180,10 @@
 //!
 //! // Insert another blob, this time using a parameter passed in from
 //! // rust (potentially with a dynamic size).
-//! db.execute("INSERT INTO test_table (content) VALUES (?)", &[ZeroBlob(64)])?;
+//! db.execute(
+//!     "INSERT INTO test_table (content) VALUES (?)",
+//!     &[ZeroBlob(64)],
+//! )?;
 //!
 //! // given a new row ID, we can reopen the blob on that row
 //! let rowid = db.last_insert_rowid();
@@ -196,8 +202,8 @@ use crate::{Connection, DatabaseName, Result};
 
 mod pos_io;
 
-/// `feature = "blob"` Handle to an open BLOB. See [`rusqlite::blob`](crate::blob) documentation for
-/// in-depth discussion.
+/// `feature = "blob"` Handle to an open BLOB. See
+/// [`rusqlite::blob`](crate::blob) documentation for in-depth discussion.
 pub struct Blob<'conn> {
     conn: &'conn Connection,
     blob: *mut ffi::sqlite3_blob,

src/busy.rs

@@ -137,9 +137,7 @@ mod test {
     #[test]
     #[ignore] // FIXME: unstable
     fn test_busy_handler() {
-        lazy_static::lazy_static! {
-            static ref CALLED: AtomicBool = AtomicBool::new(false);
-        }
+        static CALLED: AtomicBool = AtomicBool::new(false);
         fn busy_handler(_: i32) -> bool {
             CALLED.store(true, Ordering::Relaxed);
             thread::sleep(Duration::from_millis(100));

src/collation.rs

@@ -15,9 +15,9 @@ unsafe extern "C" fn free_boxed_value<T>(p: *mut c_void) {
 
 impl Connection {
     /// `feature = "collation"` Add or modify a collation.
-    pub fn create_collation<C>(&self, collation_name: &str, x_compare: C) -> Result<()>
+    pub fn create_collation<'c, C>(&'c self, collation_name: &str, x_compare: C) -> Result<()>
     where
-        C: Fn(&str, &str) -> Ordering + Send + UnwindSafe + 'static,
+        C: Fn(&str, &str) -> Ordering + Send + UnwindSafe + 'c,
     {
         self.db
             .borrow_mut()
@@ -39,9 +39,9 @@ impl Connection {
 }
 
 impl InnerConnection {
-    fn create_collation<C>(&mut self, collation_name: &str, x_compare: C) -> Result<()>
+    fn create_collation<'c, C>(&'c mut self, collation_name: &str, x_compare: C) -> Result<()>
     where
-        C: Fn(&str, &str) -> Ordering + Send + UnwindSafe + 'static,
+        C: Fn(&str, &str) -> Ordering + Send + UnwindSafe + 'c,
     {
         unsafe extern "C" fn call_boxed_closure<C>(
             arg1: *mut c_void,

src/error.rs

@@ -111,8 +111,9 @@ pub enum Error {
     InvalidParameterCount(usize, usize),
 
     /// Returned from various functions in the Blob IO positional API. For
-    /// example, [`Blob::raw_read_at_exact`](crate::blob::Blob::raw_read_at_exact)
-    /// will return it if the blob has insufficient data.
+    /// example,
+    /// [`Blob::raw_read_at_exact`](crate::blob::Blob::raw_read_at_exact) will
+    /// return it if the blob has insufficient data.
     #[cfg(feature = "blob")]
     BlobSizeError,
 }

src/functions.rs

@@ -22,8 +22,7 @@
 //!         FunctionFlags::SQLITE_UTF8 | FunctionFlags::SQLITE_DETERMINISTIC,
 //!         move |ctx| {
 //!             assert_eq!(ctx.len(), 2, "called with unexpected number of arguments");
-//!             let regexp: Arc<Regex> = ctx
-//!                 .get_or_create_aux(0, |vr| -> Result<_, BoxError> {
+//!             let regexp: Arc<Regex> = ctx.get_or_create_aux(0, |vr| -> Result<_, BoxError> {
 //!                 Ok(Regex::new(vr.as_str()?)?)
 //!             })?;
 //!             let is_match = {
@@ -334,15 +333,15 @@ impl Connection {
     /// # Failure
     ///
     /// Will return Err if the function could not be attached to the connection.
-    pub fn create_scalar_function<'a, F, T>(
-        &'a self,
+    pub fn create_scalar_function<'c, F, T>(
+        &'c self,
         fn_name: &str,
         n_arg: c_int,
         flags: FunctionFlags,
         x_func: F,
     ) -> Result<()>
     where
-        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'a,
+        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'c,
         T: ToSql,
     {
         self.db
@@ -411,15 +410,15 @@ impl Connection {
 }
 
 impl InnerConnection {
-    fn create_scalar_function<'a, F, T>(
-        &'a mut self,
+    fn create_scalar_function<'c, F, T>(
+        &'c mut self,
         fn_name: &str,
         n_arg: c_int,
         flags: FunctionFlags,
         x_func: F,
     ) -> Result<()>
     where
-        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'a,
+        F: FnMut(&Context<'_>) -> Result<T> + Send + UnwindSafe + 'c,
         T: ToSql,
     {
         unsafe extern "C" fn call_boxed_closure<F, T>(

src/hooks.rs

@@ -2,7 +2,7 @@
 #![allow(non_camel_case_types)]
 
 use std::os::raw::{c_char, c_int, c_void};
-use std::panic::catch_unwind;
+use std::panic::{catch_unwind, RefUnwindSafe};
 use std::ptr;
 
 use crate::ffi;
@@ -40,9 +40,9 @@ impl Connection {
     /// a transaction is committed.
     ///
     /// The callback returns `true` to rollback.
-    pub fn commit_hook<F>(&self, hook: Option<F>)
+    pub fn commit_hook<'c, F>(&'c self, hook: Option<F>)
     where
-        F: FnMut() -> bool + Send + 'static,
+        F: FnMut() -> bool + Send + 'c,
     {
         self.db.borrow_mut().commit_hook(hook);
     }
@@ -51,9 +51,9 @@ impl Connection {
     /// a transaction is committed.
     ///
     /// The callback returns `true` to rollback.
-    pub fn rollback_hook<F>(&self, hook: Option<F>)
+    pub fn rollback_hook<'c, F>(&'c self, hook: Option<F>)
     where
-        F: FnMut() + Send + 'static,
+        F: FnMut() + Send + 'c,
     {
         self.db.borrow_mut().rollback_hook(hook);
     }
@@ -68,12 +68,27 @@ impl Connection {
     /// - the name of the database ("main", "temp", ...),
     /// - the name of the table that is updated,
     /// - the ROWID of the row that is updated.
-    pub fn update_hook<F>(&self, hook: Option<F>)
+    pub fn update_hook<'c, F>(&'c self, hook: Option<F>)
     where
-        F: FnMut(Action, &str, &str, i64) + Send + 'static,
+        F: FnMut(Action, &str, &str, i64) + Send + 'c,
     {
         self.db.borrow_mut().update_hook(hook);
     }
+
+    /// `feature = "hooks"` Register a query progress callback.
+    ///
+    /// The parameter `num_ops` is the approximate number of virtual machine
+    /// instructions that are evaluated between successive invocations of the
+    /// `handler`. If `num_ops` is less than one then the progress handler
+    /// is disabled.
+    ///
+    /// If the progress callback returns `true`, the operation is interrupted.
+    pub fn progress_handler<F>(&self, num_ops: c_int, handler: Option<F>)
+    where
+        F: FnMut() -> bool + Send + RefUnwindSafe + 'static,
+    {
+        self.db.borrow_mut().progress_handler(num_ops, handler);
+    }
 }
 
 impl InnerConnection {
@@ -81,11 +96,12 @@ impl InnerConnection {
         self.update_hook(None::<fn(Action, &str, &str, i64)>);
         self.commit_hook(None::<fn() -> bool>);
         self.rollback_hook(None::<fn()>);
+        self.progress_handler(0, None::<fn() -> bool>);
     }
 
-    fn commit_hook<F>(&mut self, hook: Option<F>)
+    fn commit_hook<'c, F>(&'c mut self, hook: Option<F>)
     where
-        F: FnMut() -> bool + Send + 'static,
+        F: FnMut() -> bool + Send + 'c,
     {
         unsafe extern "C" fn call_boxed_closure<F>(p_arg: *mut c_void) -> c_int
         where
@@ -132,9 +148,9 @@ impl InnerConnection {
         self.free_commit_hook = free_commit_hook;
     }
 
-    fn rollback_hook<F>(&mut self, hook: Option<F>)
+    fn rollback_hook<'c, F>(&'c mut self, hook: Option<F>)
     where
-        F: FnMut() + Send + 'static,
+        F: FnMut() + Send + 'c,
     {
         unsafe extern "C" fn call_boxed_closure<F>(p_arg: *mut c_void)
         where
@@ -173,9 +189,9 @@ impl InnerConnection {
         self.free_rollback_hook = free_rollback_hook;
     }
 
-    fn update_hook<F>(&mut self, hook: Option<F>)
+    fn update_hook<'c, F>(&'c mut self, hook: Option<F>)
     where
-        F: FnMut(Action, &str, &str, i64) + Send + 'static,
+        F: FnMut(Action, &str, &str, i64) + Send + 'c,
     {
         unsafe extern "C" fn call_boxed_closure<F>(
             p_arg: *mut c_void,
@@ -236,6 +252,45 @@ impl InnerConnection {
         }
         self.free_update_hook = free_update_hook;
     }
+
+    fn progress_handler<F>(&mut self, num_ops: c_int, handler: Option<F>)
+    where
+        F: FnMut() -> bool + Send + RefUnwindSafe + 'static,
+    {
+        unsafe extern "C" fn call_boxed_closure<F>(p_arg: *mut c_void) -> c_int
+        where
+            F: FnMut() -> bool,
+        {
+            let r = catch_unwind(|| {
+                let boxed_handler: *mut F = p_arg as *mut F;
+                (*boxed_handler)()
+            });
+            if let Ok(true) = r {
+                1
+            } else {
+                0
+            }
+        }
+
+        match handler {
+            Some(handler) => {
+                let boxed_handler = Box::new(handler);
+                unsafe {
+                    ffi::sqlite3_progress_handler(
+                        self.db(),
+                        num_ops,
+                        Some(call_boxed_closure::<F>),
+                        &*boxed_handler as *const F as *mut _,
+                    )
+                }
+                self.progress_handler = Some(boxed_handler);
+            }
+            _ => {
+                unsafe { ffi::sqlite3_progress_handler(self.db(), num_ops, None, ptr::null_mut()) }
+                self.progress_handler = None;
+            }
+        };
+    }
 }
 
 unsafe fn free_boxed_hook<F>(p: *mut c_void) {
@@ -246,23 +301,20 @@ unsafe fn free_boxed_hook<F>(p: *mut c_void) {
 mod test {
     use super::Action;
     use crate::Connection;
-    use lazy_static::lazy_static;
     use std::sync::atomic::{AtomicBool, Ordering};
 
     #[test]
     fn test_commit_hook() {
         let db = Connection::open_in_memory().unwrap();
 
-        lazy_static! {
-            static ref CALLED: AtomicBool = AtomicBool::new(false);
-        }
+        let mut called = false;
         db.commit_hook(Some(|| {
-            CALLED.store(true, Ordering::Relaxed);
+            called = true;
             false
         }));
         db.execute_batch("BEGIN; CREATE TABLE foo (t TEXT); COMMIT;")
             .unwrap();
-        assert!(CALLED.load(Ordering::Relaxed));
+        assert!(called);
     }
 
     #[test]
@@ -282,33 +334,59 @@ mod test {
     fn test_rollback_hook() {
         let db = Connection::open_in_memory().unwrap();
 
-        lazy_static! {
-            static ref CALLED: AtomicBool = AtomicBool::new(false);
-        }
+        let mut called = false;
         db.rollback_hook(Some(|| {
-            CALLED.store(true, Ordering::Relaxed);
+            called = true;
         }));
         db.execute_batch("BEGIN; CREATE TABLE foo (t TEXT); ROLLBACK;")
             .unwrap();
-        assert!(CALLED.load(Ordering::Relaxed));
+        assert!(called);
     }
 
     #[test]
     fn test_update_hook() {
         let db = Connection::open_in_memory().unwrap();
 
-        lazy_static! {
-            static ref CALLED: AtomicBool = AtomicBool::new(false);
-        }
+        let mut called = false;
         db.update_hook(Some(|action, db: &str, tbl: &str, row_id| {
             assert_eq!(Action::SQLITE_INSERT, action);
             assert_eq!("main", db);
             assert_eq!("foo", tbl);
             assert_eq!(1, row_id);
-            CALLED.store(true, Ordering::Relaxed);
+            called = true;
         }));
         db.execute_batch("CREATE TABLE foo (t TEXT)").unwrap();
         db.execute_batch("INSERT INTO foo VALUES ('lisa')").unwrap();
+        assert!(called);
+    }
+
+    #[test]
+    fn test_progress_handler() {
+        let db = Connection::open_in_memory().unwrap();
+
+        static CALLED: AtomicBool = AtomicBool::new(false);
+        db.progress_handler(
+            1,
+            Some(|| {
+                CALLED.store(true, Ordering::Relaxed);
+                false
+            }),
+        );
+        db.execute_batch("BEGIN; CREATE TABLE foo (t TEXT); COMMIT;")
+            .unwrap();
         assert!(CALLED.load(Ordering::Relaxed));
     }
+
+    #[test]
+    fn test_progress_handler_interrupt() {
+        let db = Connection::open_in_memory().unwrap();
+
+        fn handler() -> bool {
+            true
+        }
+
+        db.progress_handler(1, Some(handler));
+        db.execute_batch("BEGIN; CREATE TABLE foo (t TEXT); COMMIT;")
+            .unwrap_err();
+    }
 }

src/inner_connection.rs

@@ -31,6 +31,8 @@ pub struct InnerConnection {
     pub free_rollback_hook: Option<unsafe fn(*mut ::std::os::raw::c_void)>,
     #[cfg(feature = "hooks")]
     pub free_update_hook: Option<unsafe fn(*mut ::std::os::raw::c_void)>,
+    #[cfg(feature = "hooks")]
+    pub progress_handler: Option<Box<dyn FnMut() -> bool + Send>>,
     owned: bool,
 }
 
@@ -46,6 +48,8 @@ impl InnerConnection {
             free_rollback_hook: None,
             #[cfg(feature = "hooks")]
             free_update_hook: None,
+            #[cfg(feature = "hooks")]
+            progress_handler: None,
             owned,
         }
     }

src/lib.rs

@@ -810,6 +810,67 @@ impl fmt::Debug for Connection {
     }
 }
 
+/// Batch iterator
+/// ```rust
+/// use rusqlite::{Batch, Connection, Result, NO_PARAMS};
+///
+/// fn main() -> Result<()> {
+///     let conn = Connection::open_in_memory()?;
+///     let sql = r"
+///     CREATE TABLE tbl1 (col);
+///     CREATE TABLE tbl2 (col);
+///     ";
+///     let mut batch = Batch::new(&conn, sql);
+///     while let Some(mut stmt) = batch.next()? {
+///         stmt.execute(NO_PARAMS)?;
+///     }
+///     Ok(())
+/// }
+/// ```
+#[derive(Debug)]
+pub struct Batch<'conn, 'sql> {
+    conn: &'conn Connection,
+    sql: &'sql str,
+    tail: usize,
+}
+
+impl<'conn, 'sql> Batch<'conn, 'sql> {
+    /// Constructor
+    pub fn new(conn: &'conn Connection, sql: &'sql str) -> Batch<'conn, 'sql> {
+        Batch { conn, sql, tail: 0 }
+    }
+
+    /// Iterates on each batch statements.
+    ///
+    /// Returns `Ok(None)` when batch is completed.
+    #[allow(clippy::should_implement_trait)] // fallible iterator
+    pub fn next(&mut self) -> Result<Option<Statement<'conn>>> {
+        while self.tail < self.sql.len() {
+            let sql = &self.sql[self.tail..];
+            let next = self.conn.prepare(sql)?;
+            let tail = next.stmt.tail();
+            if tail == 0 {
+                self.tail = self.sql.len();
+            } else {
+                self.tail += tail;
+            }
+            if next.stmt.is_null() {
+                continue;
+            }
+            return Ok(Some(next));
+        }
+        Ok(None)
+    }
+}
+
+impl<'conn> Iterator for Batch<'conn, '_> {
+    type Item = Result<Statement<'conn>>;
+
+    fn next(&mut self) -> Option<Result<Statement<'conn>>> {
+        self.next().transpose()
+    }
+}
+
 bitflags::bitflags! {
     /// Flags for opening SQLite database connections.
     /// See [sqlite3_open_v2](http://www.sqlite.org/c3ref/open.html) for details.
@@ -1749,6 +1810,7 @@ mod test {
                 err => panic!("Unexpected error {}", err),
             }
         }
+    }
 
     #[test]
     fn test_dynamic() {
@@ -1759,7 +1821,7 @@ mod test {
                        END;";
         db.execute_batch(sql).unwrap();
 
-            db.query_row("SELECT * FROM foo", params![], |r| {
+        db.query_row("SELECT * FROM foo", NO_PARAMS, |r| {
             assert_eq!(2, r.column_count());
             Ok(())
         })
@@ -1771,7 +1833,7 @@ mod test {
         db.execute_batch("CREATE TABLE foo(x INTEGER);").unwrap();
         let b: Box<dyn ToSql> = Box::new(5);
         db.execute("INSERT INTO foo VALUES(?)", &[b]).unwrap();
-            db.query_row("SELECT x FROM foo", params![], |r| {
+        db.query_row("SELECT x FROM foo", NO_PARAMS, |r| {
             assert_eq!(5, r.get_unwrap::<_, i32>(0));
             Ok(())
         })
@@ -1788,8 +1850,8 @@ mod test {
             ?, ?, ?, ?, ?, ?, ?, ?, ?, ?,
             ?, ?, ?, ?;",
             params![
-                    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-                    1, 1, 1, 1, 1, 1, 1, 1,
+                1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+                1, 1, 1, 1, 1, 1,
             ],
             |r| {
                 assert_eq!(1, r.get_unwrap::<_, i32>(0));
@@ -1805,7 +1867,20 @@ mod test {
         let db = checked_memory_handle();
         db.execute_batch("CREATE TABLE x(t);").unwrap();
         // `execute_batch` should be used but `execute` should also work
-            db.execute("ALTER TABLE x RENAME TO y;", params![]).unwrap();
+        db.execute("ALTER TABLE x RENAME TO y;", NO_PARAMS).unwrap();
+    }
+
+    #[test]
+    fn test_batch() {
+        let db = checked_memory_handle();
+        let sql = r"
+             CREATE TABLE tbl1 (col);
+             CREATE TABLE tbl2 (col);
+             ";
+        let batch = Batch::new(&db, sql);
+        for stmt in batch {
+            let mut stmt = stmt.unwrap();
+            stmt.execute(NO_PARAMS).unwrap();
         }
     }
 }

src/session.rs

@@ -819,9 +819,7 @@ mod test {
         db.execute_batch("CREATE TABLE foo(t TEXT PRIMARY KEY NOT NULL);")
             .unwrap();
 
-        lazy_static::lazy_static! {
-            static ref CALLED: AtomicBool = AtomicBool::new(false);
-        }
+        static CALLED: AtomicBool = AtomicBool::new(false);
         db.apply(
             &changeset,
             None::<fn(&str) -> bool>,

src/types/mod.rs

@@ -15,8 +15,8 @@
 //! `FromSql` has different behaviour depending on the SQL and Rust types, and
 //! the value.
 //!
-//! * `INTEGER` to integer: returns an `Error::IntegralValueOutOfRange` error
-//!   if the value does not fit in the Rust type.
+//! * `INTEGER` to integer: returns an `Error::IntegralValueOutOfRange` error if
+//!   the value does not fit in the Rust type.
 //! * `REAL` to integer: always returns an `Error::InvalidColumnType` error.
 //! * `INTEGER` to float: casts using `as` operator. Never fails.
 //! * `REAL` to float: casts using `as` operator. Never fails.
@@ -32,7 +32,6 @@
 //! can be parsed by SQLite's builtin
 //! [datetime](https://www.sqlite.org/lang_datefunc.html) functions.  If you
 //! want different storage for datetimes, you can use a newtype.
-//!
 #![cfg_attr(
     feature = "time",
     doc = r##"

src/util/small_cstr.rs

@@ -100,6 +100,7 @@ impl std::fmt::Debug for SmallCString {
 
 impl std::ops::Deref for SmallCString {
     type Target = CStr;
+
     #[inline]
     fn deref(&self) -> &CStr {
         self.as_cstr()

src/util/sqlite_string.rs

@@ -130,9 +130,10 @@ impl SqliteMallocString {
                     // This is safe:
                     // - `align` is never 0
                     // - `align` is always a power of 2.
-                    // - `size` needs no realignment because it's guaranteed to be
-                    //   aligned (everything is aligned to 1)
-                    // - `size` is also never zero, although this function doesn't actually require it now.
+                    // - `size` needs no realignment because it's guaranteed to be aligned
+                    //   (everything is aligned to 1)
+                    // - `size` is also never zero, although this function doesn't actually require
+                    //   it now.
                     let layout = Layout::from_size_align_unchecked(s.len().saturating_add(1), 1);
                     // Note: This call does not return.
                     handle_alloc_error(layout);