Added support for Pico Loader API v2. This makes it possible to return to Pico Launcher from homebrew.

workflow: add release pipeline

.github/workflows/nightly.yml

@@ -14,12 +14,8 @@ on:
 jobs:
   pico_launcher:
     runs-on: ubuntu-latest
-    container: skylyrac/blocksds:slim-v1.13.1
+    container: skylyrac/blocksds:slim-v1.16.0
     name: Build Pico Launcher
-    env:
-      DOTNET_CLI_TELEMETRY_OPTOUT: 1
-      DOTNET_SKIP_FIRST_TIME_EXPERIENCE: 1
-      DOTNET_SYSTEM_GLOBALIZATION_INVARIANT: 1
     steps:
       - name: Checkout repo
         uses: actions/checkout@v4
@@ -34,4 +30,4 @@ jobs:
           path: |
             _pico/
             LAUNCHER.nds
-          name: Pico Launcher
+          name: Pico_Launcher

.github/workflows/release.yml

@@ -0,0 +1,39 @@
+name: Build Pico Launcher release
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  pico_launcher:
+    runs-on: ubuntu-latest
+    container: skylyrac/blocksds:slim-v1.16.0
+    name: Build Pico Launcher
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@v4
+        with:
+          submodules: true
+      - name: Install zip
+        run:
+          apt-get update && apt-get -y install zip
+      - name: Run build script
+        run: |
+          make
+      - name: Publish build to GH Actions
+        uses: actions/upload-artifact@v4
+        with:
+          path: |
+            _pico/
+            LAUNCHER.nds
+          name: Pico_Launcher
+      - name: Package for release
+        run: |
+          mkdir Pico_Launcher
+          cp -r _pico/ LAUNCHER.nds Pico_Launcher
+          cd Pico_Launcher && zip -r $PWD.zip *
+      - name: Release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            Pico_Launcher.zip

arm9/source/globalHeap.cpp

@@ -60,6 +60,16 @@ extern "C" void* memalign(size_t alignment, size_t size)
     return result;
 }
 
+extern "C" void* calloc(size_t num, size_t size)
+{
+    void* result = malloc(num * size);
+    if (result)
+    {
+        memset(result, 0, num * size);
+    }
+    return result;
+}
+
 void* operator new(std::size_t blocksize)
 {
     return malloc(blocksize);

arm9/source/main.cpp

@@ -167,6 +167,11 @@ int main(int argc, char* argv[])
 
     rtc_init();
 
+    if (argc >= 1)
+    {
+        pload_setLauncherPath(argv[0]);
+    }
+
     memset(&gFatFs, 0, sizeof(gFatFs));
     if (dldi_init())
     {

arm9/source/picoLoaderBootstrap.cpp

@@ -10,6 +10,7 @@
 #include <libtwl/ipc/ipcFifoSystem.h>
 #include "ipcChannels.h"
 #include "fat/File.h"
+#include "core/StringUtil.h"
 #include "picoLoaderBootstrap.h"
 
 #define PICO_LOADER_9_PATH    "/_pico/picoLoader9.bin"
@@ -18,6 +19,7 @@
 typedef void (*pico_loader_9_func_t)(void);
 
 static pload_params_t sLoadParams;
+static char sLauncherPath[256] alignas(32);
 static PicoLoaderBootDrive sBootDrive;
 
 pload_params_t* pload_getLoadParams()
@@ -30,6 +32,11 @@ void pload_setBootDrive(PicoLoaderBootDrive bootDrive)
     sBootDrive = bootDrive;
 }
 
+void pload_setLauncherPath(const char* launcherPath)
+{
+    StringUtil::Copy(sLauncherPath, launcherPath, sizeof(sLauncherPath));
+}
+
 void pload_start()
 {
     mem_setVramAMapping(MEM_VRAM_AB_LCDC);
@@ -78,8 +85,13 @@ void pload_start()
     DC_InvalidateAll();
     IC_InvalidateAll();
 
-    ((pload_header7_t*)0x06840000)->bootDrive = sBootDrive;
-    dma_ntrCopy16(3, &sLoadParams, &((pload_header7_t*)0x06840000)->loadParams, sizeof(pload_params_t));
+    auto header = (pload_header7_t*)0x06840000;
+    header->bootDrive = sBootDrive;
+    dma_ntrCopy16(3, &sLoadParams, &header->loadParams, sizeof(pload_params_t));
+    if (header->apiVersion >= 2)
+    {
+        dma_ntrCopy16(3, &sLauncherPath, &header->v2.launcherPath, sizeof(header->v2.launcherPath));
+    }
     mem_setVramCMapping(MEM_VRAM_C_ARM7_00000);
     mem_setVramDMapping(MEM_VRAM_D_ARM7_20000);
     ipc_sendFifoMessage(IPC_CHANNEL_LOADER, 1);

arm9/source/picoLoaderBootstrap.h

@@ -3,4 +3,5 @@
 
 pload_params_t* pload_getLoadParams();
 void pload_setBootDrive(PicoLoaderBootDrive bootDrive);
+void pload_setLauncherPath(const char* launcherPath);
 void pload_start();

common/picoLoader7.h

@@ -1,7 +1,7 @@
 #pragma once
 
 /// @brief The Pico Loader API version supported by this header file.
-#define PICO_LOADER_API_VERSION     1
+#define PICO_LOADER_API_VERSION     2
 
 /// @brief Enum to specify the drive to boot from.
 typedef enum
@@ -35,6 +35,14 @@ typedef struct
     char arguments[256];
 } pload_params_t;
 
+/// @brief Struct representing the API version 2 part of the header of picoLoader7.bin.
+typedef struct
+{
+    /// @brief The path of the rom to return to when exiting an application.
+    ///        When this path is not set, no bootstub will be patched into homebrew applications.
+    char launcherPath[256];
+} pload_header7_v2_t;
+
 /// @brief Struct representing the header of picoLoader7.bin.
 typedef struct
 {
@@ -52,4 +60,7 @@ typedef struct
 
     /// @brief The load params, see \see pload_params_t.
     pload_params_t loadParams;
+
+    /// @brief The API version 2 part of the header. Only access this when \see apiVersion >= 2.
+    pload_header7_v2_t v2;
 } pload_header7_t;