1 /* ScummVM - Graphic Adventure Engine
2 *
3 * ScummVM is the legal property of its developers, whose names
4 * are too numerous to list here. Please refer to the COPYRIGHT
5 * file distributed with this source distribution.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20 *
21 */
22
23 #include "common/scummsys.h"
24
25 #if defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) && defined(MIPS_TARGET)
26
27 #include "backends/plugins/elf/shorts-segment-manager.h"
28
29 #include "common/debug.h"
30 #include "common/textconsole.h"
31
32 extern char __plugin_hole_start; // Indicates start of hole in program file for shorts
33 extern char __plugin_hole_end; // Indicates end of hole in program file
34 extern char _gp[]; // Value of gp register
35
36 namespace Common {
37 DECLARE_SINGLETON(ShortSegmentManager); // For singleton
38 }
39
ShortSegmentManager()40 ShortSegmentManager::ShortSegmentManager() {
41 _shortsStart = &__plugin_hole_start ; //shorts segment begins at the plugin hole we made when linking
42 _shortsEnd = &__plugin_hole_end; //and ends at the end of that hole.
43 }
44
newSegment(uint32 size,char * origAddr)45 ShortSegmentManager::Segment *ShortSegmentManager::newSegment(uint32 size, char *origAddr) {
46 char *lastAddress = origAddr;
47 Common::List<Segment *>::iterator i;
48
49 // Find a block that fits, starting from the beginning
50 for (i = _list.begin(); i != _list.end(); ++i) {
51 char *currAddress = (*i)->getStart();
52
53 if (uint32(currAddress) - uint32(lastAddress) >= size)
54 break;
55
56 lastAddress = (*i)->getEnd();
57 }
58
59 if ((Elf32_Addr)lastAddress & 3)
60 lastAddress += 4 - ((Elf32_Addr)lastAddress & 3); // Round up to multiple of 4
61
62 if (lastAddress + size > _shortsEnd) {
63 warning("elfloader: No space in shorts segment for %x bytes. Last address is %p, max address is %p.",
64 size, lastAddress, _shortsEnd);
65 return 0;
66 }
67
68 Segment *seg = new Segment(lastAddress, size, origAddr); // Create a new segment
69
70 if (lastAddress + size > _highestAddress)
71 _highestAddress = lastAddress + size; // Keep track of maximum
72
73 _list.insert(i, seg);
74
75 debug(2, "elfloader: Shorts segment size %x allocated. End = %p. Remaining space = %x. Highest so far is %p.",
76 size, lastAddress + size, _shortsEnd - _list.back()->getEnd(), _highestAddress);
77
78 return seg;
79 }
80
deleteSegment(ShortSegmentManager::Segment * seg)81 void ShortSegmentManager::deleteSegment(ShortSegmentManager::Segment *seg) {
82 debug(2, "elfloader: Deleting shorts segment from %p to %p.", seg->getStart(), seg->getEnd());
83 _list.remove(seg);
84 delete seg;
85 }
86
87 #endif // defined(DYNAMIC_MODULES) && defined(USE_ELF_LOADER) && defined(MIPS_TARGET)
88