expand the original stack to __stacksize__ instead of moving sp to a

different buffer.

libctru/source/system/allocateHeaps.c

@@ -7,18 +7,38 @@ u32 __linear_heap;
 u32 __heapBase;
 extern u32 __heap_size, __linear_heap_size;
 
+u32 __attribute__((weak)) __stacksize__ = 0x8000;
+u32 __stack_bottom;
+u32 __allocated_stack_size;
+
+void __system_allocateStack() {
+	u32 tmp=0;
+	MemInfo memInfo;
+	PageInfo pageInfo;
+
+	register u32 sp_val __asm__("sp");
+	svcQueryMemory(&memInfo, &pageInfo, sp_val);
+
+	__stacksize__ += 0xFFF;
+	__stacksize__ &= ~0xFFF;
+	__allocated_stack_size = __stacksize__ > memInfo.size ? __stacksize__ - memInfo.size: 0;
+	__stack_bottom = memInfo.base_addr - __allocated_stack_size;
+
+	if (__allocated_stack_size)
+		svcControlMemory(&tmp, __stack_bottom, 0x0, __allocated_stack_size, MEMOP_ALLOC, MEMPERM_READ | MEMPERM_WRITE);
+}
 
 void __attribute__((weak)) __system_allocateHeaps() {
 	u32 tmp=0;
 
 	// Allocate the application heap
 	__heapBase = 0x08000000;
-	svcControlMemory(&tmp, __heapBase, 0x0, __heap_size, MEMOP_ALLOC, MEMPERM_READ | MEMPERM_WRITE);
+	svcControlMemory(&tmp, __heapBase, 0x0, __heap_size - __allocated_stack_size, MEMOP_ALLOC, MEMPERM_READ | MEMPERM_WRITE);
 
 	// Allocate the linear heap
 	svcControlMemory(&__linear_heap, 0x0, 0x0, __linear_heap_size, MEMOP_ALLOC_LINEAR, MEMPERM_READ | MEMPERM_WRITE);
 	// Set up newlib heap
 	fake_heap_start = (char*)__heapBase;
-	fake_heap_end = fake_heap_start + __heap_size;
+	fake_heap_end = fake_heap_start + __heap_size - __allocated_stack_size;
 
 }

libctru/source/system/ctru_exit.c

@@ -4,6 +4,8 @@
 extern u32 __linear_heap;
 extern u32 __heapBase;
 extern u32 __heap_size, __linear_heap_size;
+extern u32 __stack_bottom;
+extern u32 __allocated_stack_size;
 extern void (*__system_retAddr)(void);
 
 void __destroy_handle_list(void);
@@ -21,7 +23,7 @@ void __attribute__((weak)) __attribute__((noreturn)) __libctru_exit(int rc)
 	svcControlMemory(&tmp, __linear_heap, 0x0, __linear_heap_size, MEMOP_FREE, 0x0);
 
 	// Unmap the application heap
-	svcControlMemory(&tmp, __heapBase, 0x0, __heap_size, MEMOP_FREE, 0x0);
+	svcControlMemory(&tmp, __heapBase, 0x0, __heap_size - __allocated_stack_size, MEMOP_FREE, 0x0);
 
 	// Close some handles
 	__destroy_handle_list();
@@ -36,3 +38,18 @@ void __attribute__((weak)) __attribute__((noreturn)) __libctru_exit(int rc)
 	// Since above did not jump, end this process
 	svcExitProcess();
 }
+
+void __system_deallocateStack() {
+	u32 tmp=0;
+
+	if (__allocated_stack_size)
+		svcControlMemory(&tmp, __stack_bottom, 0x0, __allocated_stack_size, MEMOP_FREE, 0x0);
+}
+
+void __attribute__((noreturn)) __ctru_exit(int rc)
+{
+	__libc_fini_array();
+	__appExit();
+	__system_deallocateStack();
+	__libctru_exit(rc);
+}

libctru/source/system/initSystem.c

@@ -10,9 +10,11 @@ void (*__system_retAddr)(void);
 // Data from _prm structure
 extern void* __service_ptr; // used to detect if we're run from a homebrew launcher
 
+void __system_allocateStack();
 void __system_allocateHeaps();
 void __system_initArgv();
 void __appInit();
+void __libc_init_array();
 
 
 void __ctru_exit(int rc);
@@ -32,9 +34,17 @@ void __attribute__((weak)) __libctru_init(void (*retAddr)(void))
 	if (__sync_init)
 		__sync_init();
 
+	__system_allocateStack();
 	__system_allocateHeaps();
 
 	// Build argc/argv if present
 	__system_initArgv();
 
 }
+
+void initSystem(void (*retAddr)(void))
+{
+	__libctru_init(retAddr);
+	__appInit();
+	__libc_init_array();
+}

libctru/source/system/stack_adjust.s

@@ -1,57 +0,0 @@
-
-	.arm
-	.align 2
-
-	.global	initSystem
-	.type	initSystem,	%function
-
-initSystem:
-	ldr	r2, =saved_stack
-	str	sp, [r2]
-	str	lr, [r2,#4]
-
-	bl	__libctru_init
-
-	ldr	r2, =fake_heap_start
-	ldr	sp, [r2]
-
-	ldr	r3, =__stacksize__
-	ldr	r3, [r3]
-	add sp, sp, r3
-	add	sp, sp, #7
-	bics	sp, sp, #7
-	str	sp, [r2]
-
-
-	bl	__appInit
-	bl	__libc_init_array
-
-	ldr	r2, =saved_stack
-	ldr	lr, [r2,#4]
- 	bx	lr
-
-
-	.global	__ctru_exit
-	.type	__ctru_exit,	%function
-
-__ctru_exit:
-	bl	__libc_fini_array
-	bl	__appExit
-
-	ldr	r2, =saved_stack
-	ldr	sp, [r2]
-	b	__libctru_exit
-
-	.data
-	.align 2
-__stacksize__:
-	.word	32 * 1024
-	.weak	__stacksize__
-
-
-	.bss
-	.align 2
-saved_stack:
-	.space 8
-
-