From: fincs <fincs.alt1@gmail.com>
Date: Wed, 20 Aug 2014 20:01:50 +0000 (+0200)
Subject: Implement initSystem(), __ctru_exit() and __system_argc/argv
X-Git-Tag: v0.2.0~134
X-Git-Url: https://chaos.moe/g/?a=commitdiff_plain;h=a90ee009f835837e988e9a4b1565be316e6fa102;p=corbenik%2Fctrulib.git

Implement initSystem(), __ctru_exit() and __system_argc/argv
---

diff --git a/libctru/source/initSystem.c b/libctru/source/initSystem.c
new file mode 100644
index 0000000..1f51c03
--- /dev/null
+++ b/libctru/source/initSystem.c
@@ -0,0 +1,99 @@
+#include <sys/iosupport.h>
+#include <3ds/types.h>
+#include <3ds/svc.h>
+#include <string.h>
+
+// System globals we define here
+int __system_argc;
+char** __system_argv;
+void (*__system_retAddr)(void);
+
+// Data from _prm structure
+extern void* __service_ptr; // used to detect if we're run from a homebrew launcher
+extern u32 __heap_size;
+extern const char* __system_arglist;
+
+// newlib definitions we need
+void __libc_fini_array();
+extern char* fake_heap_start;
+extern char* fake_heap_end;
+
+static void initArgv();
+
+void __ctru_exit(int rc)
+{
+	// Run the global destructors
+	__libc_fini_array();
+
+	// TODO: APT exit goes here
+
+	// Unmap the heap
+	u32 blockAddr;
+	svcControlMemory(&blockAddr, 0x08000000, 0x0, __heap_size, MEMOP_FREE, 0x0);
+
+	// Jump to the loader if it provided a callback
+	if (__system_retAddr)
+		__system_retAddr();
+
+	// Since above did not jump: hang
+	for (;;);
+}
+
+void initSystem(void (*retAddr)(void))
+{
+	// Register newlib exit() syscall
+	__syscalls.exit = __ctru_exit;
+	__system_retAddr = __service_ptr ? retAddr : NULL;
+
+	// Allocate the application heap
+	u32 blockAddr;
+	svcControlMemory(&blockAddr, 0x08000000, 0x0, __heap_size, MEMOP_ALLOC, 0x3);
+
+	// Set up newlib heap
+	fake_heap_start = (char*)0x08000000;
+	fake_heap_end = fake_heap_start + __heap_size;
+
+	// Build argc/argv if present
+	initArgv();
+
+	// TODO: APT init goes here
+}
+
+void initArgv()
+{
+	int i;
+	const char* temp = __system_arglist;
+
+	// Check if the argument list is present
+	if (!temp)
+		return;
+
+	// Retrieve argc
+	__system_argc = *(u32*)temp;
+	temp += sizeof(u32);
+
+	// Find the end of the argument data
+	for (i = 0; i < __system_argc; i ++)
+	{
+		for (; *temp; temp ++);
+		temp ++;
+	}
+
+	// Reserve heap memory for argv data
+	u32 argSize = temp - __system_arglist - sizeof(u32);
+	__system_argv = (char**)fake_heap_start;
+	fake_heap_start += sizeof(char**)*(__system_argc + 1);
+	char* argCopy = fake_heap_start;
+	fake_heap_start += argSize;
+
+	// Fill argv array
+	memcpy(argCopy, __system_arglist, argSize);
+	temp = argCopy;
+	for (i = 0; i < __system_argc; i ++)
+	{
+		__system_argv[i] = (char*)temp;
+		for (; *temp; temp ++);
+		temp ++;
+	}
+	__system_argv[__system_argc] = NULL;
+}