Initial commit

backends/plugins/elf/shorts-segment-manager.cpp

@@ -0,0 +1,86 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "common/scummsys.h"
+
+#if defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) && defined(MIPS_TARGET)
+
+#include "backends/plugins/elf/shorts-segment-manager.h"
+
+#include "common/debug.h"
+#include "common/textconsole.h"
+
+extern char __plugin_hole_start;	// Indicates start of hole in program file for shorts
+extern char __plugin_hole_end;		// Indicates end of hole in program file
+extern char _gp[];					// Value of gp register
+
+namespace Common {
+DECLARE_SINGLETON(ShortSegmentManager);	// For singleton
+}
+
+ShortSegmentManager::ShortSegmentManager() {
+	_shortsStart = &__plugin_hole_start ;	//shorts segment begins at the plugin hole we made when linking
+	_shortsEnd = &__plugin_hole_end;		//and ends at the end of that hole.
+}
+
+ShortSegmentManager::Segment *ShortSegmentManager::newSegment(uint32 size, char *origAddr) {
+	char *lastAddress = origAddr;
+	Common::List<Segment *>::iterator i;
+
+	// Find a block that fits, starting from the beginning
+	for (i = _list.begin(); i != _list.end(); ++i) {
+		char *currAddress = (*i)->getStart();
+
+		if (uint32(currAddress) - uint32(lastAddress) >= size)
+			break;
+
+		lastAddress = (*i)->getEnd();
+	}
+
+	if ((Elf32_Addr)lastAddress & 3)
+		lastAddress += 4 - ((Elf32_Addr)lastAddress & 3);	// Round up to multiple of 4
+
+	if (lastAddress + size > _shortsEnd) {
+		warning("elfloader: No space in shorts segment for %x bytes. Last address is %p, max address is %p.",
+				size, lastAddress, _shortsEnd);
+		return 0;
+	}
+
+	Segment *seg = new Segment(lastAddress, size, origAddr);	// Create a new segment
+
+	if (lastAddress + size > _highestAddress)
+		_highestAddress = lastAddress + size;	// Keep track of maximum
+
+	_list.insert(i, seg);
+
+	debug(2, "elfloader: Shorts segment size %x allocated. End = %p. Remaining space = %x. Highest so far is %p.",
+			size, lastAddress + size, _shortsEnd - _list.back()->getEnd(), _highestAddress);
+
+	return seg;
+}
+
+void ShortSegmentManager::deleteSegment(ShortSegmentManager::Segment *seg) {
+	debug(2, "elfloader: Deleting shorts segment from %p to %p.", seg->getStart(), seg->getEnd());
+	_list.remove(seg);
+	delete seg;
+}
+
+#endif // defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) && defined(MIPS_TARGET)