Use read-write ring buffer

6 files changed, 153 insertions, 137 deletions

diff --git a/bin/gui/control.c b/bin/gui/control.c
index 545c095..d4191a1 100644
--- a/bin/gui/control.c
+++ b/bin/gui/control.c
@@ -309,7 +309,7 @@ get_statistics (ThreadData *data, gdouble *mean, gdouble *sigma, guint *_max, gu
     guint n = data->width * data->height;
 
     if (data->pixel_size == 1) {
-        guint8 *input = (guint8 *) uca_ring_buffer_get_current_pointer (data->buffer);
+        guint8 *input = (guint8 *) uca_ring_buffer_peek_pointer (data->buffer);
 
         for (gint i = 0; i < n; i++) {
             guint8 val = input[i];
@@ -325,7 +325,7 @@ get_statistics (ThreadData *data, gdouble *mean, gdouble *sigma, guint *_max, gu
         }
     }
     else {
-        guint16 *input = (guint16 *) uca_ring_buffer_get_current_pointer (data->buffer);
+        guint16 *input = (guint16 *) uca_ring_buffer_peek_pointer (data->buffer);
 
         for (gint i = 0; i < n; i++) {
             guint16 val = input[i];
@@ -407,7 +407,7 @@ on_motion_notify (GtkWidget *event_box, GdkEventMotion *event, ThreadData *data)
         gpointer *buffer;
         GString *string;
 
-        buffer = uca_ring_buffer_get_current_pointer (data->buffer);
+        buffer = uca_ring_buffer_peek_pointer (data->buffer);
         string = g_string_new_len (NULL, 32);
         gint i = (data->display_y / data->zoom_factor) * data->width + data->display_x / data->zoom_factor;
 
@@ -560,9 +560,6 @@ update_pixbuf (ThreadData *data)
 
     gtk_widget_queue_draw_area (data->image, 0, 0, data->display_width, data->display_height);
 
-    egg_histogram_view_update (EGG_HISTOGRAM_VIEW (data->histogram_view),
-                               uca_ring_buffer_get_current_pointer (data->buffer));
-
     if ((data->adj_width > 0) && (data->adj_height > 0)) {
         x = data->from_x;
         y = data->from_y;
@@ -681,48 +678,52 @@ preview_frames (void *args)
     while (data->state == RUNNING) {
         gpointer *buffer;
 
-        buffer = uca_ring_buffer_get_current_pointer (data->buffer);
+        buffer = uca_ring_buffer_peek_pointer (data->buffer);
         uca_camera_grab (data->camera, buffer, &error);
 
-        if (error == NULL) {
-            up_and_down_scale (data, buffer);
-
-            gdk_threads_enter ();
-            update_pixbuf (data);
+        if (error != NULL) {
+            print_and_free_error (&error);
+            continue;
+        }
 
-            if ((data->ev_x >= 0) && (data->ev_y >= 0) && (data->ev_y <= data->display_height) && (data->ev_x <= data->display_width)) {
-                GString *string;
-                string = g_string_new_len (NULL, 32);
-                gint i = (data->display_y / data->zoom_factor) * data->width + data->display_x / data->zoom_factor;
+        up_and_down_scale (data, buffer);
 
-                if (data->pixel_size == 1) {
-                    guint8 *input = (guint8 *) buffer;
-                    guint8 val = input[i];
-                    g_string_printf (string, "val = %i", val);
-                    gtk_label_set_text (data->val_label, string->str);
-                }
-                else if (data->pixel_size == 2) {
-                    guint16 *input = (guint16 *) buffer;
-                    guint16 val = input[i];
-                    g_string_printf (string, "val = %i", val);
-                    gtk_label_set_text (data->val_label, string->str);
-                }
+        gdk_threads_enter ();
 
-                g_string_printf (string, "x = %i", data->display_x);
-                gtk_label_set_text (data->x_label, string->str);
+        update_pixbuf (data);
+        egg_histogram_view_update (EGG_HISTOGRAM_VIEW (data->histogram_view), buffer);
 
-                g_string_printf (string, "y = %i", data->display_y);
-                gtk_label_set_text (data->y_label, string->str);
+        if ((data->ev_x >= 0) && (data->ev_y >= 0) &&
+            (data->ev_y <= data->display_height) && (data->ev_x <= data->display_width)) {
+            GString *string;
+            string = g_string_new_len (NULL, 32);
+            gint i = (data->display_y / data->zoom_factor) * data->width + data->display_x / data->zoom_factor;
 
-                g_string_free (string, TRUE);
+            if (data->pixel_size == 1) {
+                guint8 *input = (guint8 *) buffer;
+                guint8 val = input[i];
+                g_string_printf (string, "val = %i", val);
+                gtk_label_set_text (data->val_label, string->str);
+            }
+            else if (data->pixel_size == 2) {
+                guint16 *input = (guint16 *) buffer;
+                guint16 val = input[i];
+                g_string_printf (string, "val = %i", val);
+                gtk_label_set_text (data->val_label, string->str);
             }
 
-            gdk_threads_leave ();
+            g_string_printf (string, "x = %i", data->display_x);
+            gtk_label_set_text (data->x_label, string->str);
 
-            counter++;
+            g_string_printf (string, "y = %i", data->display_y);
+            gtk_label_set_text (data->y_label, string->str);
+
+            g_string_free (string, TRUE);
         }
-        else
-            print_and_free_error (&error);
+
+        gdk_threads_leave ();
+
+        counter++;
     }
     return NULL;
 }
@@ -749,11 +750,10 @@ record_frames (gpointer args)
         if (n_max > 0 && n_frames >= n_max)
             break;
 
-        buffer = uca_ring_buffer_get_current_pointer (data->buffer);
+        buffer = uca_ring_buffer_get_write_pointer (data->buffer);
         uca_camera_grab (data->camera, buffer, NULL);
 
         if (error == NULL) {
-            uca_ring_buffer_proceed (data->buffer);
             n_frames++;
             data->n_recorded++;
         }
@@ -806,9 +806,8 @@ update_current_frame (ThreadData *data)
     if (n_max > 0)
         index = (index + data->n_recorded - n_max) % n_max;
 
-    uca_ring_buffer_set_current_pointer (data->buffer, index);
-
-    buffer = uca_ring_buffer_get_current_pointer (data->buffer);
+    buffer = uca_ring_buffer_get_pointer (data->buffer, index);
+    egg_histogram_view_update (EGG_HISTOGRAM_VIEW (data->histogram_view), buffer);
     up_and_down_scale (data, buffer);
     update_pixbuf (data);
 }
@@ -948,9 +947,9 @@ download_frames (ThreadData *data)
     uca_ring_buffer_reset (data->buffer);
 
     while (error == NULL) {
-        buffer = uca_ring_buffer_get_current_pointer (data->buffer);
+        buffer = uca_ring_buffer_get_write_pointer (data->buffer);
         uca_camera_grab (data->camera, buffer, &error);
-        uca_ring_buffer_proceed (data->buffer);
+
         gdk_threads_enter ();
         gtk_adjustment_set_value (data->download_adjustment, current_frame++);
         gdk_threads_leave ();
@@ -1002,7 +1001,7 @@ static void
 update_zoomed_pixbuf (ThreadData *data)
 {
     update_pixbuf_dimensions (data);
-    up_and_down_scale (data, uca_ring_buffer_get_current_pointer (data->buffer));
+    up_and_down_scale (data, uca_ring_buffer_peek_pointer (data->buffer));
     update_pixbuf (data);
 }
 
@@ -1068,7 +1067,7 @@ on_colormap_changed (GtkComboBox *widget, ThreadData *data)
     data->colormap = map;
     update_pixbuf_dimensions (data);
 
-    up_and_down_scale (data, uca_ring_buffer_get_current_pointer (data->buffer));
+    up_and_down_scale (data, uca_ring_buffer_peek_pointer (data->buffer));
     update_pixbuf (data);
 }
 
@@ -1178,7 +1177,7 @@ create_main_window (GtkBuilder *builder, const gchar* camera_name)
     ring_buffer = uca_ring_buffer_new (image_size, n_frames);
 
     egg_histogram_view_update (EGG_HISTOGRAM_VIEW (histogram_view),
-                               uca_ring_buffer_get_current_pointer (ring_buffer));
+                               uca_ring_buffer_peek_pointer (ring_buffer));
 
     pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, width, height);
     gtk_image_set_from_pixbuf (GTK_IMAGE (image), pixbuf);
diff --git a/bin/tools/grab.c b/bin/tools/grab.c
index 50c70a8..a3dd544 100644
--- a/bin/tools/grab.c
+++ b/bin/tools/grab.c
@@ -77,7 +77,7 @@ write_tiff (UcaRingBuffer *buffer,
         gpointer data;
         gsize offset = 0;
 
-        data = uca_ring_buffer_get_pointer (buffer, i);
+        data = uca_ring_buffer_get_read_pointer (buffer);
 
         TIFFSetField (tif, TIFFTAG_IMAGEWIDTH, width);
         TIFFSetField (tif, TIFFTAG_IMAGELENGTH, height);
@@ -119,7 +119,7 @@ write_raw (UcaRingBuffer *buffer,
             filename = g_strdup_printf ("frame-%08i.raw", i);
 
         fp = fopen(filename, "wb");
-        data = uca_ring_buffer_get_pointer (buffer, i);
+        data = uca_ring_buffer_get_read_pointer (buffer);
 
         fwrite (data, size, 1, fp);
         fclose (fp);
@@ -169,8 +169,7 @@ record_frames (UcaCamera *camera, Options *opts)
     while (1) {
         gdouble elapsed;
 
-        uca_camera_grab (camera, uca_ring_buffer_get_current_pointer (buffer), &error);
-        uca_ring_buffer_proceed (buffer);
+        uca_camera_grab (camera, uca_ring_buffer_get_write_pointer (buffer), &error);
 
         if (error != NULL)
             return error;
diff --git a/plugins/mock/uca-mock-camera.c b/plugins/mock/uca-mock-camera.c
index 18ac7db..b75882e 100644
--- a/plugins/mock/uca-mock-camera.c
+++ b/plugins/mock/uca-mock-camera.c
@@ -155,6 +155,7 @@ static void
 print_current_frame (UcaMockCameraPrivate *priv, gchar *buffer)
 {
     guint number = priv->current_frame;
+    char default_line[priv->width];
     guint divisor = 10000000;
     int x = 1;
 
@@ -165,45 +166,33 @@ print_current_frame (UcaMockCameraPrivate *priv, gchar *buffer)
         x += DIGIT_WIDTH + 1;
     }
 
-
-    //Rainbow pattern is the same for every row. Just calculate one single
-    //Scanline, so we can reuse it and dont have to do the whole calculation
-    //for every row again.
-    char default_line[priv->width];
     for (int p = 0; p < priv->width; p++) {
         default_line[p] = (char) ((p*256) / (priv->width));
     }
 
-
-    //Use memcpy to quickly fill every row with the precalculated rainbow
-    //pattern
     for (guint y = 16; y < priv->height; y++) {
         guint index = y * priv->width;
-        memcpy(&buffer[index], &default_line[0], priv->width);
+        memcpy (&buffer[index], &default_line[0], priv->width);
     }
     
-    #ifdef __CREATE_RANDOM_IMAGE_DATA__
-    
-        //This block will fill a square at the center of the image with noraml
-        //distributed random data
-        const double mean = 128.0;
-        const double std = 32.0;
-    
-        for (guint y = (priv->height/3); y < ((priv->height*2)/3); y++) {
-            guint row_start = y * priv->width;
-            for (guint i = (priv->width/3); i < ((priv->width*2)/3); i++) {
-                int index = row_start + i;
-                double u1 = g_rand_double(priv->rand);
-                double u2 = g_rand_double(priv->rand);
-                double r = sqrt(-2 * log(u1)) * cos(2 * G_PI * u2);
-                buffer[index] = (guint8) (r * std + mean);
-            }
+#ifdef __CREATE_RANDOM_IMAGE_DATA__
+    //This block will fill a square at the center of the image with noraml
+    //distributed random data
+    const double mean = 128.0;
+    const double std = 32.0;
+
+    for (guint y = (priv->height/3); y < ((priv->height*2)/3); y++) {
+        guint row_start = y * priv->width;
+
+        for (guint i = (priv->width/3); i < ((priv->width*2)/3); i++) {
+            int index = row_start + i;
+            double u1 = g_rand_double (priv->rand);
+            double u2 = g_rand_double (priv->rand);
+            double r = sqrt (-2 * log(u1)) * cos(2 * G_PI * u2);
+            buffer[index] = (guint8) (r * std + mean);
         }
-        
-    #endif
-    
-    
-    
+    }
+#endif
 }
 
 static gpointer
diff --git a/src/uca-ring-buffer.c b/src/uca-ring-buffer.c
index 40d7a25..98ede8f 100644
--- a/src/uca-ring-buffer.c
+++ b/src/uca-ring-buffer.c
@@ -26,8 +26,11 @@ struct _UcaRingBufferPrivate {
     guchar  *data;
     gsize    block_size;
     guint    n_blocks_total;
-    guint    n_blocks_used;
-    guint    current_index;
+    guint    write_index;
+    guint    read_index;
+    guint    read;
+    guint    written;
+    gboolean full;
 };
 
 enum {
@@ -57,8 +60,9 @@ uca_ring_buffer_reset (UcaRingBuffer *buffer)
 {
     g_return_if_fail (UCA_IS_RING_BUFFER (buffer));
 
-    buffer->priv->n_blocks_used = 0;
-    buffer->priv->current_index = 0;
+    buffer->priv->write_index = 0;
+    buffer->priv->read_index = 0;
+    buffer->priv->full = FALSE;
 }
 
 gsize
@@ -68,6 +72,13 @@ uca_ring_buffer_get_block_size (UcaRingBuffer *buffer)
     return buffer->priv->block_size;
 }
 
+gboolean
+uca_ring_buffer_available (UcaRingBuffer *buffer)
+{
+    g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), FALSE);
+    return buffer->priv->read_index < buffer->priv->write_index;
+}
+
 /**
  * uca_ring_buffer_get_current_pointer:
  * @buffer: A #UcaRingBuffer object
@@ -79,66 +90,63 @@ uca_ring_buffer_get_block_size (UcaRingBuffer *buffer)
  * Return value: (transfer none): Pointer to data block
  */
 gpointer
-uca_ring_buffer_get_current_pointer (UcaRingBuffer *buffer)
+uca_ring_buffer_get_read_pointer (UcaRingBuffer *buffer)
 {
     UcaRingBufferPrivate *priv;
+    gpointer data;
 
     g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), NULL);
     priv = buffer->priv;
-    return priv->data + (priv->current_index % priv->n_blocks_total) * priv->block_size;
+    data = priv->data + (priv->read_index % priv->n_blocks_total) * priv->block_size;
+    priv->read_index++;
+    return data;
 }
 
-void
-uca_ring_buffer_set_current_pointer (UcaRingBuffer *buffer,
-                                     guint index)
+gpointer
+uca_ring_buffer_get_write_pointer (UcaRingBuffer *buffer)
 {
-    g_return_if_fail (UCA_IS_RING_BUFFER (buffer));
-    g_assert (index < buffer->priv->n_blocks_total);
-    buffer->priv->current_index = index;
+    UcaRingBufferPrivate *priv;
+    gpointer data;
+
+    g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), NULL);
+
+    priv = buffer->priv;
+    data = priv->data + (priv->write_index % priv->n_blocks_total) * priv->block_size;
+    priv->write_index++;
+
+    if ((priv->write_index - priv->read_index) == priv->n_blocks_total)
+        priv->full = TRUE;
+
+    return data;
 }
 
-/**
- * uca_ring_buffer_get_pointer:
- * @buffer: A #UcaRingBuffer object
- * @index: Block index to get the pointer for
- *
- * Get a pointer to the data for @index block. @index must be less than
- * :num-blocks.
- *
- * Return value: (transfer none): Pointer to data block
- */
 gpointer
-uca_ring_buffer_get_pointer (UcaRingBuffer *buffer,
-                             guint index)
+uca_ring_buffer_peek_pointer (UcaRingBuffer *buffer)
 {
     UcaRingBufferPrivate *priv;
-
     g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), NULL);
-    g_assert (index < buffer->priv->n_blocks_total);
     priv = buffer->priv;
-    return priv->data + ((priv->current_index - priv->n_blocks_used + index) % priv->n_blocks_total) * priv->block_size;
+    return ((guint8 *) priv->data) + ((priv->write_index % priv->n_blocks_total) * priv->block_size);
 }
 
-guint
-uca_ring_buffer_get_num_blocks (UcaRingBuffer *buffer)
+gpointer
+uca_ring_buffer_get_pointer (UcaRingBuffer *buffer,
+                             guint          index)
 {
-    g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), 0);
-    return buffer->priv->n_blocks_used;
+    UcaRingBufferPrivate *priv;
+    g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), NULL);
+    priv = buffer->priv;
+    return ((guint8 *) priv->data) + (((priv->read_index + index) % priv->n_blocks_total) * priv->block_size);
 }
 
-void
-uca_ring_buffer_proceed (UcaRingBuffer *buffer)
+guint
+uca_ring_buffer_get_num_blocks (UcaRingBuffer *buffer)
 {
     UcaRingBufferPrivate *priv;
-    g_return_if_fail (UCA_IS_RING_BUFFER (buffer));
 
+    g_return_val_if_fail (UCA_IS_RING_BUFFER (buffer), 0);
     priv = buffer->priv;
-    priv->current_index++;
-
-    if (priv->n_blocks_used < priv->n_blocks_total)
-        priv->n_blocks_used++;
-    else
-        priv->current_index = priv->current_index % priv->n_blocks_total;
+    return priv->write_index < priv->n_blocks_total ? priv->write_index : priv->n_blocks_total;
 }
 
 static void
@@ -259,9 +267,7 @@ uca_ring_buffer_init (UcaRingBuffer *buffer)
     UcaRingBufferPrivate *priv;
     priv = buffer->priv = UCA_RING_BUFFER_GET_PRIVATE (buffer);
 
-    priv->n_blocks_used = 0;
-    priv->current_index = 0;
-    priv->block_size = 0;
     priv->n_blocks_total = 0;
+    priv->block_size = 0;
     priv->data = NULL;
 }
diff --git a/src/uca-ring-buffer.h b/src/uca-ring-buffer.h
index 03e2cae..c90f2d2 100644
--- a/src/uca-ring-buffer.h
+++ b/src/uca-ring-buffer.h
@@ -32,13 +32,14 @@ UcaRingBuffer * uca_ring_buffer_new                 (gsize          block_size,
                                                      guint          n_blocks);
 void            uca_ring_buffer_reset               (UcaRingBuffer *buffer);
 gsize           uca_ring_buffer_get_block_size      (UcaRingBuffer *buffer);
-gpointer        uca_ring_buffer_get_current_pointer (UcaRingBuffer *buffer);
-void            uca_ring_buffer_set_current_pointer (UcaRingBuffer *buffer,
-                                                     guint          index);
-gpointer        uca_ring_buffer_get_pointer         (UcaRingBuffer *buffer,
-                                                     guint          index);
 guint           uca_ring_buffer_get_num_blocks      (UcaRingBuffer *buffer);
+gboolean        uca_ring_buffer_available           (UcaRingBuffer *buffer);
 void            uca_ring_buffer_proceed             (UcaRingBuffer *buffer);
+gpointer        uca_ring_buffer_get_read_pointer    (UcaRingBuffer *buffer);
+gpointer        uca_ring_buffer_get_write_pointer   (UcaRingBuffer *buffer);
+gpointer        uca_ring_buffer_get_pointer         (UcaRingBuffer *buffer,
+                                                     guint          index);
+gpointer        uca_ring_buffer_peek_pointer        (UcaRingBuffer *buffer);
 
 GType uca_ring_buffer_get_type (void);
 
diff --git a/test/test-ring-buffer.c b/test/test-ring-buffer.c
index 2026408..02bf1eb 100644
--- a/test/test-ring-buffer.c
+++ b/test/test-ring-buffer.c
@@ -14,7 +14,7 @@ test_new_constructor (void)
 
     g_assert (uca_ring_buffer_get_block_size (buffer) == 512);
     g_assert (uca_ring_buffer_get_num_blocks (buffer) == 0);
-    g_assert (uca_ring_buffer_get_current_pointer (buffer) != NULL);
+    g_assert (uca_ring_buffer_get_write_pointer (buffer) != NULL);
 
     g_object_unref (buffer);
 }
@@ -28,7 +28,7 @@ test_new_func (void)
 
     g_assert (uca_ring_buffer_get_block_size (buffer) == 512);
     g_assert (uca_ring_buffer_get_num_blocks (buffer) == 0);
-    g_assert (uca_ring_buffer_get_current_pointer (buffer) != NULL);
+    g_assert (uca_ring_buffer_get_write_pointer (buffer) != NULL);
 
     g_object_unref (buffer);
 }
@@ -41,26 +41,47 @@ test_ring (void)
 
     buffer = uca_ring_buffer_new (512, 2);
 
-    data = uca_ring_buffer_get_current_pointer (buffer);
+    data = uca_ring_buffer_get_write_pointer (buffer);
     data[0] = 0xBADF00D;
-    uca_ring_buffer_proceed (buffer);
 
-    data = uca_ring_buffer_get_current_pointer (buffer);
+    g_assert (uca_ring_buffer_available (buffer));
+    g_assert (uca_ring_buffer_get_num_blocks (buffer) == 1);
+
+    data = uca_ring_buffer_get_write_pointer (buffer);
     data[0] = 0xDEADBEEF;
-    uca_ring_buffer_proceed (buffer);
 
     g_assert (uca_ring_buffer_get_num_blocks (buffer) == 2);
     
-    data = uca_ring_buffer_get_current_pointer (buffer);
+    data = uca_ring_buffer_get_read_pointer (buffer);
     g_assert (data[0] == 0xBADF00D);
 
-    data = uca_ring_buffer_get_pointer (buffer, 1);
+    data = uca_ring_buffer_get_read_pointer (buffer);
     g_assert (data[0] == 0xDEADBEEF);
 
+    g_assert (!uca_ring_buffer_available (buffer));
+
     uca_ring_buffer_reset (buffer);
     g_assert (uca_ring_buffer_get_num_blocks (buffer) == 0);
 }
 
+static void
+test_overwrite (void)
+{
+    UcaRingBuffer *buffer;
+    guint32 *data;
+
+    buffer = uca_ring_buffer_new (512, 1);
+
+    data = uca_ring_buffer_get_write_pointer (buffer);
+    data[0] = 0xBADF00D;
+
+    data = uca_ring_buffer_get_write_pointer (buffer);
+    data[0] = 0xDEADBEEF;
+
+    data = uca_ring_buffer_get_read_pointer (buffer);
+    g_assert (data[0] == 0xDEADBEEF);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -70,6 +91,7 @@ main (int argc, char *argv[])
     g_test_add_func ("/ringbuffer/new/constructor", test_new_constructor);
     g_test_add_func ("/ringbuffer/new/func", test_new_func);
     g_test_add_func ("/ringbuffer/functionality ", test_ring);
+    g_test_add_func ("/ringbuffer/overwrite ", test_overwrite);
 
     return g_test_run ();
 }