3DS: Implement dynamic plugins

Allows a full build to run on old generation devices

1 files changed, 24 insertions, 8 deletions

diff --git a/backends/plugins/elf/elf-loader.cpp b/backends/plugins/elf/elf-loader.cpp
index 5198fa8088..39f1f7dfa5 100644
--- a/backends/plugins/elf/elf-loader.cpp
+++ b/backends/plugins/elf/elf-loader.cpp
@@ -50,8 +50,7 @@ DLObject::DLObject() :
 
 DLObject::~DLObject() {
 	discardSymtab();
-	ELFMemMan.pluginDeallocate(_segment);
-	_segment = 0;
+	discardSegment();
 }
 
 // Expel the symbol table from memory
@@ -65,11 +64,12 @@ void DLObject::discardSymtab() {
 	_symbol_cnt = 0;
 }
 
-// Unload all objects from memory
-void DLObject::unload() {
-	discardSymtab();
-
-	ELFMemMan.pluginDeallocate(_segment);
+void DLObject::discardSegment() {
+	if (_segment) {
+		// Restore default protection before returning memory
+		protectMemory(_segment, _segmentSize, PF_R | PF_W);
+		deallocateMemory(_segment, _segmentSize);
+	}
 
 	_segment = 0;
 	_segmentSize = 0;
@@ -77,6 +77,12 @@ void DLObject::unload() {
 	_segmentVMA = 0;
 }
 
+// Unload all objects from memory
+void DLObject::unload() {
+	discardSymtab();
+	discardSegment();
+}
+
 bool DLObject::readElfHeader(Elf32_Ehdr *ehdr) {
 	assert(_file);
 
@@ -163,7 +169,7 @@ bool DLObject::readProgramHeaders(Elf32_Ehdr *ehdr, Elf32_Phdr *phdr, Elf32_Half
 }
 
 bool DLObject::loadSegment(Elf32_Phdr *phdr) {
-	_segment = (byte *)ELFMemMan.pluginAllocate(phdr->p_align, phdr->p_memsz);
+	_segment = (byte *)allocateMemory(phdr->p_align, phdr->p_memsz);
 
 	if (!_segment) {
 		warning("elfloader: Out of memory.");
@@ -402,6 +408,8 @@ bool DLObject::load() {
 		return false;
 	}
 
+	protectMemory(_segment, _segmentSize, phdr.p_flags);
+
 	return true;
 }
 
@@ -488,4 +496,12 @@ void *DLObject::symbol(const char *name) {
 	return 0;
 }
 
+void *DLObject::allocateMemory(uint32 align, uint32 size) {
+	return ELFMemMan.pluginAllocate(align, size);
+}
+
+void DLObject::deallocateMemory(void *ptr, uint32 size) {
+	ELFMemMan.pluginDeallocate(ptr);
+}
+
 #endif /* defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) */