Drop stb_image from Switch OTA launcher with a pre-baked logo asset.

native/switch-ota-launcher/Makefile

@@ -46,7 +46,8 @@ APP_VERSION	?=	0.0.0
 
 # Prefer project Switch icon if present
 ICON		:=	$(TOPDIR)/../../assets/switch/icon.jpg
-LOGO_SRC	:=	$(TOPDIR)/../../assets/logo/logo.png
+LOGO_RGBA_SRC	:=	$(TOPDIR)/assets/logo.rgba
+LOGO_ROMFS	:=	$(CURDIR)/$(ROMFS)/logo.rgba
 
 #---------------------------------------------------------------------------------
 ARCH	:=	-march=armv8-a+crc+crypto -mtune=cortex-a57 -mtp=soft -fPIE
@@ -148,7 +149,8 @@ bootstrap-romfs:
 
 sync-romfs: bootstrap-romfs
 	@mkdir -p $(CURDIR)/$(ROMFS)
-	@cp -f $(LOGO_SRC) $(CURDIR)/$(ROMFS)/logo.png
+	@[ -f "$(LOGO_RGBA_SRC)" ] || (echo "missing $(LOGO_RGBA_SRC) — run: python3 scripts/switch/bake_ota_logo.py" && exit 1)
+	@cp -f "$(LOGO_RGBA_SRC)" "$(LOGO_ROMFS)"
 	@if ! curl -sfL --time-cond $(CACERT_ROMFS) -o $(CACERT_ROMFS) $(CACERT_URL); then \
 		[ -f $(CACERT_ROMFS) ] || (echo "sync-romfs: failed to fetch cacert.pem" && exit 1); \
 	fi
@@ -161,7 +163,7 @@ $(BUILD): sync-romfs
 clean:
 	@echo clean ...
 	@rm -fr $(BUILD) $(TARGET).nro $(TARGET).nacp $(TARGET).elf $(TARGET).lst build-host
-	@rm -f $(CURDIR)/$(ROMFS)/logo.png
+	@rm -f $(CURDIR)/$(ROMFS)/logo.rgba $(CURDIR)/$(ROMFS)/logo.png
 
 host-test:
 	@mkdir -p build-host

native/switch-ota-launcher/README.md

@@ -59,6 +59,18 @@ scripts/switch/build_ota_launcher.sh
 
 Docker fallback uses the same pin as fused builds (`scripts/switch/dkp-docker.image`).
 
+## OTA logo asset
+
+The launcher draws a pre-scaled logo from `romfs:/logo.rgba` (no PNG decoder in
+the NRO). The baked blob lives at `assets/logo.rgba` and is copied into romfs at
+build time. After changing `assets/logo/logo.png`, regenerate:
+
+```bash
+python3 scripts/switch/bake_ota_logo.py
+```
+
+Requires Pillow, or on macOS uses `sips` when Pillow is not installed.
+
 ## Packaging
 
 `scripts/switch/pack_sd_zip.sh GAME_NRO VERSION OUT_ZIP LAUNCHER_NRO` writes both

native/switch-ota-launcher/src/ota_ui.c

@@ -12,12 +12,10 @@
 #if defined(__SWITCH__)
 #include <switch.h>
 
-#define STB_IMAGE_IMPLEMENTATION
-#define STBI_ONLY_PNG
-#define STBI_NO_THREAD_LOCALS
-#include "../third_party/stb_image.h"
 #include "../third_party/font8x8_basic.h"
 
+#define OTA_LOGO_ROMFS "romfs:/logo.rgba"
+
 #define FB_W 1280
 #define FB_H 720
 
@@ -261,25 +259,47 @@ static void blit_logo(u32 *fb, u32 stride_px, int dst_x, int dst_y, int max_w) {
 
 static void load_logo(void) {
   if (g_logo) return;
-  /* romfs is mounted in ota_net_init() before the release check runs. */
-  int w = 0, h = 0, n = 0;
-  unsigned char *data = stbi_load("romfs:/logo.png", &w, &h, &n, 4);
-  if (!data || w <= 0 || h <= 0) {
-    if (data) stbi_image_free(data);
+  FILE *fp = fopen(OTA_LOGO_ROMFS, "rb");
+  if (!fp) return;
+
+  unsigned char header[8];
+  if (fread(header, 1, sizeof(header), fp) != sizeof(header)) {
+    fclose(fp);
     return;
   }
+
+  int w = (int)(header[0] | (header[1] << 8) | (header[2] << 16) | (header[3] << 24));
+  int h = (int)(header[4] | (header[5] << 8) | (header[6] << 16) | (header[7] << 24));
+  if (w <= 0 || h <= 0 || w > 2048 || h > 2048) {
+    fclose(fp);
+    return;
+  }
+
+  size_t nbytes = (size_t)w * (size_t)h * 4u;
+  unsigned char *data = (unsigned char *)malloc(nbytes);
+  if (!data) {
+    fclose(fp);
+    return;
+  }
+  if (fread(data, 1, nbytes, fp) != nbytes) {
+    free(data);
+    fclose(fp);
+    return;
+  }
+  fclose(fp);
+
   g_logo = (u32 *)malloc((size_t)w * (size_t)h * sizeof(u32));
   if (!g_logo) {
-    stbi_image_free(data);
+    free(data);
     return;
   }
   for (int i = 0; i < w * h; i++) {
-    unsigned char *p = data + i * 4;
+    unsigned char *p = data + (size_t)i * 4u;
     g_logo[i] = RGBA8(p[0], p[1], p[2], p[3]);
   }
+  free(data);
   g_logo_w = w;
   g_logo_h = h;
-  stbi_image_free(data);
 }
 
 static int ui_ensure(void) {