1 files changed, 36 insertions, 0 deletions

diff --git a/apps/plugins/sudoku/generator.c b/apps/plugins/sudoku/generator.c
index d43e970ab8..037798d761 100644
--- a/apps/plugins/sudoku/generator.c
+++ b/apps/plugins/sudoku/generator.c
@@ -357,6 +357,8 @@ findmoves( void )
 {
     int i;
 
+    rb->yield();
+
     idx_possible = 0;
     for( i = 0 ; i < 9 ; ++i )
     {
@@ -392,6 +394,9 @@ void
 pairs( int el, int (*idx_fn)( int, int ) )
 {
     int i, j, k, mask, idx;
+
+    rb->yield();
+
     for( i = 0 ; i < 8 ; ++i )
         if( 7 == digits[ i ] ) /* 2 digits unknown */
             for( j = i + 1 ; j < 9 ; ++j )
@@ -419,6 +424,8 @@ exmask( int mask, int block, int el, int (*idx_fn)( int, int ) )
 {
     int i, idx;
 
+    rb->yield();
+
     for( i = 0 ; i < 9 ; ++i )
     {
         idx = (*idx_fn)( el, i );
@@ -434,6 +441,8 @@ exblock( int block, int el, int (*idx_fn)( int, int ) )
 {
     int i, idx, mask;
 
+    rb->yield();
+
     /* By assumption, all unknown squares in the block appear in the
      * same row/column, so to construct a mask for these squares, it
      * is sufficient to invert the mask for the known squares in the
@@ -455,6 +464,8 @@ block( int el )
 {
     int i, idx = 0, row, col;
 
+    rb->yield();
+
     /* Find first unknown square */
     for( i = 0 ; i < 9 && !IS_EMPTY( idx = idx_block( el, i ) ) ; ++i )
         ;
@@ -487,6 +498,8 @@ common( int el )
 {
     int i, idx, row, col, digit, mask;
 
+    rb->yield();
+
     for( digit = 1 ; digit <= 9 ; ++digit )
     {
         mask = DIGIT_STATE( digit );
@@ -525,6 +538,8 @@ position2( int el )
 {
     int digit, digit2, i, mask, mask2, posn, count, idx;
 
+    rb->yield();
+
     /* Calculate positions of each digit within block */
     for( digit = 1 ; digit <= 9 ; ++digit )
     {
@@ -574,6 +589,8 @@ allmoves( void )
 {
     int i, n;
 
+    rb->yield();
+
     n = findmoves( );
     if( 0 < n )
         return n;
@@ -619,6 +636,8 @@ findhints( void )
 {
     int i, n, mutated = 0;
 
+    rb->yield();
+
     n = findmoves( );
     if( n < 2 )
     {
@@ -687,6 +706,8 @@ deterministic( void )
 {
     int i, n;
 
+    rb->yield();
+
     n = allmoves( );
     while( 0 < n )
     {
@@ -720,6 +741,9 @@ int
 choice( void )
 {
     int i, n;
+
+    rb->yield();
+
     for( n = i = 0 ; i < 81 ; ++i )
         if( IS_EMPTY( i ) )
         {
@@ -746,6 +770,8 @@ static
 int
 choose( int idx, int digit )
 {
+    rb->yield();
+
     for( ; digit <= 9 ; ++digit )
         if( !DISALLOWED( idx, digit ) )
         {
@@ -770,6 +796,8 @@ backtrack( void )
 {
     int digit, idx;
 
+    rb->yield();
+
     for( ; 0 <= --idx_history ; )
         if( history[ idx_history ] & CHOICE )
         {
@@ -796,6 +824,8 @@ solve( void )
 {
     int idx;
 
+    rb->yield();
+
     while( 1 )
     {
         if( 0 == deterministic( ) )
@@ -870,6 +900,8 @@ classify( void )
 {
     int i, score;
 
+    rb->yield();
+
     pass = 0;
     clear_moves( );
     if( -1 == solve( ) )
@@ -1049,9 +1081,13 @@ start:
     for( i = 0 ; i < len_tmplt ; ++i )
         fill( tmplt[ i ], digits[ i % 9 ] );
 
+    rb->yield();
+
     if( 0 != solve( ) || idx_history < 81 )
         goto start;
 
+    rb->yield();
+
     for( i = 0 ; i < len_tmplt ; ++i )
         board[ tmplt[ i ] ] |= FIXED;