Dav1dPlay: Split FIFO to different files

To un-clutter the main dav1dplay.c, move the fifo to its own
file and header.

4 files changed, 186 insertions, 87 deletions

diff --git a/examples/dav1dplay.c b/examples/dav1dplay.c
index bcd4835..cc873d0 100644
--- a/examples/dav1dplay.c
+++ b/examples/dav1dplay.c
@@ -40,6 +40,7 @@
 #include "dav1d/dav1d.h"
 
 #include "tools/input/input.h"
+#include "dp_fifo.h"
 
 /**
  * Settings structure
@@ -60,93 +61,6 @@ typedef struct {
 #define DAV1D_EVENT_NEW_FRAME 1
 #define DAV1D_EVENT_DEC_QUIT  2
 
-/*
- * Fifo helper functions
- */
-typedef struct dp_fifo
-{
-    SDL_mutex *lock;
-    SDL_cond *cond_change;
-    size_t capacity;
-    size_t count;
-    void **entries;
-} Dav1dPlayPtrFifo;
-
-static void dp_fifo_destroy(Dav1dPlayPtrFifo *fifo)
-{
-    assert(fifo->count == 0);
-    SDL_DestroyMutex(fifo->lock);
-    SDL_DestroyCond(fifo->cond_change);
-    free(fifo->entries);
-    free(fifo);
-}
-
-static Dav1dPlayPtrFifo *dp_fifo_create(size_t capacity)
-{
-    Dav1dPlayPtrFifo *fifo;
-
-    assert(capacity > 0);
-    if (capacity <= 0)
-        return NULL;
-
-    fifo = malloc(sizeof(*fifo));
-    if (fifo == NULL)
-        return NULL;
-
-    fifo->capacity = capacity;
-    fifo->count = 0;
-
-    fifo->lock = SDL_CreateMutex();
-    if (fifo->lock == NULL) {
-        free(fifo);
-        return NULL;
-    }
-    fifo->cond_change = SDL_CreateCond();
-    if (fifo->cond_change == NULL) {
-        SDL_DestroyMutex(fifo->lock);
-        free(fifo);
-        return NULL;
-    }
-
-    fifo->entries = calloc(capacity, sizeof(void*));
-    if (fifo->entries == NULL) {
-        dp_fifo_destroy(fifo);
-        return NULL;
-    }
-
-    return fifo;
-}
-
-static void dp_fifo_push(Dav1dPlayPtrFifo *fifo, void *element)
-{
-    SDL_LockMutex(fifo->lock);
-    while (fifo->count == fifo->capacity)
-        SDL_CondWait(fifo->cond_change, fifo->lock);
-    fifo->entries[fifo->count++] = element;
-    if (fifo->count == 1)
-        SDL_CondSignal(fifo->cond_change);
-    SDL_UnlockMutex(fifo->lock);
-}
-
-static void *dp_fifo_array_shift(void **arr, size_t len)
-{
-    void *shifted_element = arr[0];
-    for (size_t i = 1; i < len; ++i)
-        arr[i-1] = arr[i];
-    return shifted_element;
-}
-
-static void *dp_fifo_shift(Dav1dPlayPtrFifo *fifo)
-{
-    SDL_LockMutex(fifo->lock);
-    while (fifo->count == 0)
-        SDL_CondWait(fifo->cond_change, fifo->lock);
-    void *res = dp_fifo_array_shift(fifo->entries, fifo->count--);
-    if (fifo->count == fifo->capacity - 1)
-        SDL_CondSignal(fifo->cond_change);
-    SDL_UnlockMutex(fifo->lock);
-    return res;
-}
 
 /**
  * Renderer info
diff --git a/examples/dp_fifo.c b/examples/dp_fifo.c
new file mode 100644
index 0000000..243d2e9
--- /dev/null
+++ b/examples/dp_fifo.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright © 2019, VideoLAN and dav1d authors
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <SDL.h>
+#include <assert.h>
+
+#include "dp_fifo.h"
+
+// FIFO structure
+struct dp_fifo
+{
+    SDL_mutex *lock;
+    SDL_cond *cond_change;
+    size_t capacity;
+    size_t count;
+    void **entries;
+};
+
+
+Dav1dPlayPtrFifo *dp_fifo_create(size_t capacity)
+{
+    Dav1dPlayPtrFifo *fifo;
+
+    assert(capacity > 0);
+    if (capacity <= 0)
+        return NULL;
+
+    fifo = malloc(sizeof(*fifo));
+    if (fifo == NULL)
+        return NULL;
+
+    fifo->capacity = capacity;
+    fifo->count = 0;
+
+    fifo->lock = SDL_CreateMutex();
+    if (fifo->lock == NULL) {
+        free(fifo);
+        return NULL;
+    }
+    fifo->cond_change = SDL_CreateCond();
+    if (fifo->cond_change == NULL) {
+        SDL_DestroyMutex(fifo->lock);
+        free(fifo);
+        return NULL;
+    }
+
+    fifo->entries = calloc(capacity, sizeof(void*));
+    if (fifo->entries == NULL) {
+        dp_fifo_destroy(fifo);
+        return NULL;
+    }
+
+    return fifo;
+}
+
+// Destroy FIFO
+void dp_fifo_destroy(Dav1dPlayPtrFifo *fifo)
+{
+    assert(fifo->count == 0);
+    SDL_DestroyMutex(fifo->lock);
+    SDL_DestroyCond(fifo->cond_change);
+    free(fifo->entries);
+    free(fifo);
+}
+
+// Push to FIFO
+void dp_fifo_push(Dav1dPlayPtrFifo *fifo, void *element)
+{
+    SDL_LockMutex(fifo->lock);
+    while (fifo->count == fifo->capacity)
+        SDL_CondWait(fifo->cond_change, fifo->lock);
+    fifo->entries[fifo->count++] = element;
+    if (fifo->count == 1)
+        SDL_CondSignal(fifo->cond_change);
+    SDL_UnlockMutex(fifo->lock);
+}
+
+// Helper that shifts the FIFO array
+static void *dp_fifo_array_shift(void **arr, size_t len)
+{
+    void *shifted_element = arr[0];
+    for (size_t i = 1; i < len; ++i)
+        arr[i-1] = arr[i];
+    return shifted_element;
+}
+
+// Get item from FIFO
+void *dp_fifo_shift(Dav1dPlayPtrFifo *fifo)
+{
+    SDL_LockMutex(fifo->lock);
+    while (fifo->count == 0)
+        SDL_CondWait(fifo->cond_change, fifo->lock);
+    void *res = dp_fifo_array_shift(fifo->entries, fifo->count--);
+    if (fifo->count == fifo->capacity - 1)
+        SDL_CondSignal(fifo->cond_change);
+    SDL_UnlockMutex(fifo->lock);
+    return res;
+}
+
+
diff --git a/examples/dp_fifo.h b/examples/dp_fifo.h
new file mode 100644
index 0000000..a94b089
--- /dev/null
+++ b/examples/dp_fifo.h
@@ -0,0 +1,61 @@
+/*
+ * Copyright © 2019, VideoLAN and dav1d authors
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * Dav1dPlay FIFO helper
+ */
+
+typedef struct dp_fifo Dav1dPlayPtrFifo;
+
+/* Create a FIFO
+ *
+ * Creates a FIFO with the given capacity.
+ * If the capacity is reached, new inserts into the FIFO
+ * will block until enough space is available again.
+ */
+Dav1dPlayPtrFifo *dp_fifo_create(size_t capacity);
+
+/* Destroy a FIFO
+ *
+ * The FIFO must be empty before it is destroyed!
+ */
+void dp_fifo_destroy(Dav1dPlayPtrFifo *fifo);
+
+/* Shift FIFO
+ *
+ * Return the first item from the FIFO, thereby removing it from
+ * the FIFO and making room for new entries.
+ */
+void *dp_fifo_shift(Dav1dPlayPtrFifo *fifo);
+
+/* Push to FIFO
+ *
+ * Add an item to the end of the FIFO.
+ * If the FIFO is full, this call will block until there is again enough
+ * space in the FIFO, so calling this from the "consumer" thread if no
+ * other thread will call dp_fifo_shift will lead to a deadlock.
+ */
+void dp_fifo_push(Dav1dPlayPtrFifo *fifo, void *element);
diff --git a/examples/meson.build b/examples/meson.build
index bad1d90..0e856d0 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -35,6 +35,7 @@ endif
 # dav1d player sources
 dav1dplay_sources = files(
     'dav1dplay.c',
+    'dp_fifo.c',
 )
 
 sdl2_dependency = dependency('sdl2', version: '>= 2.0.1', required: true)