capssc: Add CaptureJpegScreenShot (#407)

nx/include/switch/services/capssc.h

@@ -7,6 +7,9 @@
 #pragma once
 #include "../types.h"
 #include "../sf/service.h"
+#include "vi.h"
+
+#define CAPSSC_JPEG_BUFFER_SIZE 0x80000
 
 /// Initialize caps:sc. Only available on [2.0.0+].
 Result capsscInitialize(void);
@@ -23,12 +26,22 @@ Service* capsscGetServiceSession(void);
  * @note buffer_index and buffer_count correspond to buffers with size 0x384000(1280*720*4). These must not be negative.
  * @param buf Output buffer containing the RGBA8 image.
  * @param size Size of buf, should be 0x384000(1280*720*4) * buffer_count.
- * @param layer_stack Value 0 can be used for this.
+ * @param layer_stack \ref ViLayerStack
  * @param width Image width, must be 1280.
  * @param height Image height, must be 720.
  * @param buffer_count Total number of output image buffers.
  * @param buffer_index Starting image buffer index. Must be < buffer_count.
  * @param timeout Timeout in nanoseconds. A default value of 100000000 can be used.
  */
-Result capsscCaptureRawImageWithTimeout(void* buf, size_t size, u32 layer_stack, u64 width, u64 height, s64 buffer_count, s64 buffer_index, u64 timeout);
+Result capsscCaptureRawImageWithTimeout(void* buf, size_t size, ViLayerStack layer_stack, u64 width, u64 height, s64 buffer_count, s64 buffer_index, s64 timeout);
 
+/**
+ * @brief This takes a screenshot, with the screenshot being written as jpeg into the output buffer.
+ * @note Only available on [9.0.0+]. Requires debug mode before [10.0.0].
+ * @param out_jpeg_size Pointer to write the size of the captured jpeg to.
+ * @param jpeg_buf Output buffer containing the JPEG image.
+ * @param jpeg_buf_size Size of jpeg_buf, official software uses 0x80000.
+ * @param layer_stack \ref ViLayerStack
+ * @param timeout Timeout in nanoseconds.
+ */
+Result capsscCaptureJpegScreenShot(u64* out_jpeg_size, void* jpeg_buf, size_t jpeg_buf_size, ViLayerStack layer_stack, s64 timeout);

nx/include/switch/services/vi.h

@@ -56,6 +56,18 @@ typedef enum {
     ViPowerState_On_Deprecated = 1, ///< [1.0.0 - 2.3.0] Screen is on.
 } ViPowerState;
 
+/// Used as argument to many capture functions.
+typedef enum {
+    ViLayerStack_Default             = 0,  ///< Default layer stack, includes all layers.
+    ViLayerStack_Lcd                 = 1,  ///< Includes only layers for the LCD.
+    ViLayerStack_Screenshot          = 2,  ///< Includes only layers for user screenshots.
+    ViLayerStack_Recording           = 3,  ///< Includes only layers for recording videos.
+    ViLayerStack_LastFrame           = 4,  ///< Includes only layers for the last applet-transition frame.
+    ViLayerStack_Arbitrary           = 5,  ///< Captures some arbitrary layer. This is normally only for am.
+    ViLayerStack_ApplicationForDebug = 6,  ///< Captures layers for the current application. This is normally used by creport/debugging tools.
+    ViLayerStack_Null                = 10, ///< Layer stack for the empty display.
+} ViLayerStack;
+
 Result viInitialize(ViServiceType service_type);
 void viExit(void);
 

nx/source/services/capssc.c

@@ -26,15 +26,15 @@ Service* capsscGetServiceSession(void) {
     return &g_capsscSrv;
 }
 
-Result capsscCaptureRawImageWithTimeout(void* buf, size_t size, u32 layer_stack, u64 width, u64 height, s64 buffer_count, s64 buffer_index, u64 timeout) {
+Result capsscCaptureRawImageWithTimeout(void* buf, size_t size, ViLayerStack layer_stack, u64 width, u64 height, s64 buffer_count, s64 buffer_index, s64 timeout) {
     const struct {
-        u32 layer_stack;
+        s32 layer_stack;
         u32 pad;
         u64 width;
         u64 height;
         s64 buffer_count;
         s64 buffer_index;
-        u64 timeout;
+        s64 timeout;
     } in = { layer_stack, 0, width, height, buffer_count, buffer_index, timeout };
 
     return serviceDispatchIn(&g_capsscSrv, 2, in,
@@ -43,3 +43,18 @@ Result capsscCaptureRawImageWithTimeout(void* buf, size_t size, u32 layer_stack,
     );
 }
 
+Result capsscCaptureJpegScreenShot(u64* out_jpeg_size, void* jpeg_buf, size_t jpeg_buf_size, ViLayerStack layer_stack, s64 timeout) {
+    if (hosversionBefore(9,0,0))
+        return MAKERESULT(Module_Libnx, LibnxError_IncompatSysVer);
+
+    const struct {
+        s32 layer_stack;
+        u32 pad;
+        s64 timeout;
+    } in = { layer_stack, 0, timeout };
+
+    return serviceDispatchInOut(&g_capsscSrv, 1204, in, *out_jpeg_size,
+        .buffer_attrs = { SfBufferAttr_HipcMapTransferAllowsNonSecure | SfBufferAttr_HipcMapAlias | SfBufferAttr_Out },
+        .buffers = { { jpeg_buf, jpeg_buf_size } },
+    );
+}