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|
/* 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 2
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL: https://scummvm.svn.sourceforge.net/svnroot/scummvm/scummvm/branches/gsoc2010-plugins/backends/platform/ps2/ps2loader.cpp $
* TODO: $ID
*
*/
#if defined(DYNAMIC_MODULES) && defined(__PS2__)
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <malloc.h>
#include <unistd.h>
#include <sys/_default_fcntl.h>
#include <ps2utils.h>
#include "backends/platform/ps2/ps2loader.h"
//#include "backends/platform/ps2/powerman.h" //TODO
//#define __PS2_DEBUG_PLUGINS__
#ifdef __PS2_DEBUG_PLUGINS__
#define DBG(x,...) fprintf(stderr,x, ## __VA_ARGS__)
#else
#define DBG(x,...)
#endif
#define seterror(x,...) fprintf(stderr,x, ## __VA_ARGS__)
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
DECLARE_SINGLETON(ShortSegmentManager) // For singleton
// Get rid of symbol table in memory
void DLObject::discard_symtab() {
free(_symtab);
free(_strtab);
_symtab = NULL;
_strtab = NULL;
_symbol_cnt = 0;
}
// Unload all objects from memory
void DLObject::unload() {
discard_symtab();
free(_segment);
_segment = NULL;
if (_shortsSegment) {
ShortsMan.deleteSegment(_shortsSegment);
_shortsSegment = NULL;
}
}
/**
* Follow the instruction of a relocation section.
*
* @param fd File Descriptor
* @param offset Offset into the File
* @param size Size of relocation section
* @param relSegment Base address of relocated segment in memory (memory offset)
*
*/
bool DLObject::relocate(int fd, unsigned long offset, unsigned long size, void *relSegment) {
Elf32_Rel *rel = NULL; // relocation entry
// Allocate memory for relocation table
if (!(rel = (Elf32_Rel *)malloc(size))) {
seterror("Out of memory.");
return false;
}
// Read in our relocation table
if (lseek(fd, offset, SEEK_SET) < 0 ||
read(fd, rel, size) != (ssize_t)size) {
seterror("Relocation table load failed.");
free(rel);
return false;
}
// Treat each relocation entry. Loop over all of them
int cnt = size / sizeof(*rel);
DBG("Loaded relocation table. %d entries. base address=%p\n", cnt, relSegment);
bool seenHi16 = false; // For treating HI/LO16 commands
int firstHi16 = -1; // Mark the point of the first hi16 seen
Elf32_Addr ahl = 0; // Calculated addend
int a = 0; // Addend: taken from the target
unsigned int *lastTarget = 0; // For processing hi16 when lo16 arrives
unsigned int relocation = 0;
int debugRelocs[10] = {0}; // For debugging
int extendedHi16 = 0; // Count extended hi16 treatments
Elf32_Addr lastHiSymVal = 0;
bool hi16InShorts = false;
#define DEBUG_NUM 2
// Loop over relocation entries
for (int i = 0; i < cnt; i++) {
// Get the symbol this relocation entry is referring to
Elf32_Sym *sym = (Elf32_Sym *)(_symtab) + (REL_INDEX(rel[i].r_info));
// Get the target instruction in the code
unsigned int *target = (unsigned int *)((char *)relSegment + rel[i].r_offset);
unsigned int origTarget = *target; // Save for debugging
// Act differently based on the type of relocation
switch (REL_TYPE(rel[i].r_info)) {
case R_MIPS_HI16: // Absolute addressing.
if (sym->st_shndx < SHN_LOPROC && // Only shift for plugin section (ie. has a real section index)
firstHi16 < 0) { // Only process first in block of HI16s
firstHi16 = i; // Keep the first Hi16 we saw
seenHi16 = true;
ahl = (*target & 0xffff) << 16; // Take lower 16 bits shifted up
lastHiSymVal = sym->st_value;
hi16InShorts = (ShortsMan.inGeneralSegment((char *)sym->st_value)); // Fix for problem with switching btw segments
if (debugRelocs[0]++ < DEBUG_NUM) // Print only a set number
DBG("R_MIPS_HI16: i=%d, offset=%x, ahl = %x, target = %x\n",
i, rel[i].r_offset, ahl, *target);
}
break;
case R_MIPS_LO16: // Absolute addressing. Needs a HI16 to come before it
if (sym->st_shndx < SHN_LOPROC) { // Only shift for plugin section. (ie. has a real section index)
if (!seenHi16) { // We MUST have seen HI16 first
seterror("R_MIPS_LO16 w/o preceding R_MIPS_HI16 at relocation %d!\n", i);
free(rel);
return false;
}
// Fix: bug in gcc makes LO16s connect to wrong HI16s sometimes (shorts and regular segment)
// Note that we can check the entire shorts segment because the executable's shorts don't belong to this plugin section
// and will be screened out above
bool lo16InShorts = ShortsMan.inGeneralSegment((char *)sym->st_value);
// Correct the bug by getting the proper value in ahl (taken from the current symbol)
if ((hi16InShorts && !lo16InShorts) || (!hi16InShorts && lo16InShorts)) {
ahl -= (lastHiSymVal & 0xffff0000); // We assume gcc meant the same offset
ahl += (sym->st_value & 0xffff0000);
}
ahl &= 0xffff0000; // Clean lower 16 bits for repeated LO16s
a = *target & 0xffff; // Take lower 16 bits of the target
a = (a << 16) >> 16; // Sign extend them
ahl += a; // Add lower 16 bits. AHL is now complete
// Fix: we can have LO16 access to the short segment sometimes
if (lo16InShorts) {
relocation = ahl + _shortsSegment->getOffset(); // Add in the short segment offset
} else // It's in the regular segment
relocation = ahl + (Elf32_Addr)_segment; // Add in the new offset for the segment
if (firstHi16 >= 0) { // We haven't treated the HI16s yet so do it now
for (int j = firstHi16; j < i; j++) {
if (REL_TYPE(rel[j].r_info) != R_MIPS_HI16) continue; // Skip over non-Hi16s
lastTarget = (unsigned int *)((char *)relSegment + rel[j].r_offset); // get hi16 target
*lastTarget &= 0xffff0000; // Clear the lower 16 bits of the last target
*lastTarget |= (relocation >> 16) & 0xffff; // Take the upper 16 bits of the relocation
if (relocation & 0x8000)(*lastTarget)++; // Subtle: we need to add 1 to the HI16 in this case
}
firstHi16 = -1; // Reset so we'll know we treated it
} else {
extendedHi16++;
}
*target &= 0xffff0000; // Clear the lower 16 bits of current target
*target |= relocation & 0xffff; // Take the lower 16 bits of the relocation
if (debugRelocs[1]++ < DEBUG_NUM)
DBG("R_MIPS_LO16: i=%d, offset=%x, a=%x, ahl = %x, lastTarget = %x, origt = %x, target = %x\n",
i, rel[i].r_offset, a, ahl, *lastTarget, origTarget, *target);
if (lo16InShorts && debugRelocs[2]++ < DEBUG_NUM)
DBG("R_MIPS_LO16s: i=%d, offset=%x, a=%x, ahl = %x, lastTarget = %x, origt = %x, target = %x\n",
i, rel[i].r_offset, a, ahl, *lastTarget, origTarget, *target);
}
break;
case R_MIPS_26: // Absolute addressing (for jumps and branches only)
if (sym->st_shndx < SHN_LOPROC) { // Only relocate for main segment
a = *target & 0x03ffffff; // Get 26 bits' worth of the addend
a = (a << 6) >> 6; // Sign extend a
relocation = ((a << 2) + (Elf32_Addr)_segment) >> 2; // a already points to the target. Subtract our offset
*target &= 0xfc000000; // Clean lower 26 target bits
*target |= (relocation & 0x03ffffff);
if (debugRelocs[3]++ < DEBUG_NUM)
DBG("R_MIPS_26: i=%d, offset=%x, symbol=%d, stinfo=%x, a=%x, origTarget=%x, target=%x\n",
i, rel[i].r_offset, REL_INDEX(rel[i].r_info), sym->st_info, a, origTarget, *target);
} else {
if (debugRelocs[4]++ < DEBUG_NUM)
DBG("R_MIPS_26: i=%d, offset=%x, symbol=%d, stinfo=%x, a=%x, origTarget=%x, target=%x\n",
i, rel[i].r_offset, REL_INDEX(rel[i].r_info), sym->st_info, a, origTarget, *target);
}
break;
case R_MIPS_GPREL16: // GP Relative addressing
if (_shortsSegment->getOffset() != 0 && // Only relocate if we shift the shorts section
ShortsMan.inGeneralSegment((char *)sym->st_value)) { // Only relocate things in the plugin hole
a = *target & 0xffff; // Get 16 bits' worth of the addend
a = (a << 16) >> 16; // Sign extend it
relocation = a + _shortsSegment->getOffset();
*target &= 0xffff0000; // Clear the lower 16 bits of the target
*target |= relocation & 0xffff;
if (debugRelocs[5]++ < DEBUG_NUM)
DBG("R_MIPS_GPREL16: i=%d, a=%x, gpVal=%x, origTarget=%x, target=%x, offset=%x\n",
i, a, _gpVal, origTarget, *target, _shortsSegment->getOffset());
}
break;
case R_MIPS_32: // Absolute addressing
if (sym->st_shndx < SHN_LOPROC) { // Only shift for plugin section.
a = *target; // Get full 32 bits of addend
if (ShortsMan.inGeneralSegment((char *)sym->st_value)) // Check if we're in the shorts segment
relocation = a + _shortsSegment->getOffset(); // Shift by shorts offset
else // We're in the main section
relocation = a + (Elf32_Addr)_segment; // Shift by main offset
*target = relocation;
if (debugRelocs[6]++ < DEBUG_NUM)
DBG("R_MIPS_32: i=%d, a=%x, origTarget=%x, target=%x\n", i, a, origTarget, *target);
}
break;
default:
seterror("Unknown relocation type %x at relocation %d.\n", REL_TYPE(rel[i].r_info), i);
free(rel);
return false;
}
}
DBG("Done with relocation. extendedHi16=%d\n\n", extendedHi16);
free(rel);
return true;
}
bool DLObject::readElfHeader(int fd, Elf32_Ehdr *ehdr) {
// Start reading the elf header. Check for errors
if (read(fd, ehdr, sizeof(*ehdr)) != sizeof(*ehdr) ||
memcmp(ehdr->e_ident, ELFMAG, SELFMAG) || // Check MAGIC
ehdr->e_type != ET_EXEC || // Check for executable
ehdr->e_machine != EM_MIPS || // Check for MIPS machine type
ehdr->e_phentsize < sizeof(Elf32_Phdr) || // Check for size of program header
ehdr->e_shentsize != sizeof(Elf32_Shdr)) { // Check for size of section header
seterror("Invalid file type.");
return false;
}
DBG("phoff = %d, phentsz = %d, phnum = %d\n",
ehdr->e_phoff, ehdr->e_phentsize, ehdr->e_phnum);
return true;
}
bool DLObject::readProgramHeaders(int fd, Elf32_Ehdr *ehdr, Elf32_Phdr *phdr, int num) {
// Read program header
if (lseek(fd, ehdr->e_phoff + sizeof(*phdr)*num, SEEK_SET) < 0 ||
read(fd, phdr, sizeof(*phdr)) != sizeof(*phdr)) {
seterror("Program header load failed.");
return false;
}
// Check program header values
if (phdr->p_type != PT_LOAD || phdr->p_filesz > phdr->p_memsz) {
seterror("Invalid program header.");
return false;
}
DBG("offs = %x, filesz = %x, memsz = %x, align = %x\n",
phdr->p_offset, phdr->p_filesz, phdr->p_memsz, phdr->p_align);
return true;
}
bool DLObject::loadSegment(int fd, Elf32_Phdr *phdr) {
char *baseAddress = 0;
// We need to take account of non-allocated segment for shorts
if (phdr->p_flags & PF_X) { // This is a relocated segment
// Attempt to allocate memory for segment
int extra = phdr->p_vaddr % phdr->p_align; // Get extra length TODO: check logic here
DBG("extra mem is %x\n", extra);
if (phdr->p_align < 0x10000) phdr->p_align = 0x10000; // Fix for wrong alignment on e.g. AGI
if (!(_segment = (char *)memalign(phdr->p_align, phdr->p_memsz + extra))) {
seterror("Out of memory.\n");
return false;
}
DBG("allocated segment @ %p\n", _segment);
// Get offset to load segment into
baseAddress = (char *)_segment + phdr->p_vaddr;
_segmentSize = phdr->p_memsz + extra;
} else { // This is a shorts section.
_shortsSegment = ShortsMan.newSegment(phdr->p_memsz, (char *)phdr->p_vaddr);
baseAddress = _shortsSegment->getStart();
DBG("shorts segment @ %p to %p. Segment wants to be at %x. Offset=%x\n",
_shortsSegment->getStart(), _shortsSegment->getEnd(), phdr->p_vaddr, _shortsSegment->getOffset());
}
// Set bss segment to 0 if necessary (assumes bss is at the end)
if (phdr->p_memsz > phdr->p_filesz) {
DBG("Setting %p to %p to 0 for bss\n", baseAddress + phdr->p_filesz, baseAddress + phdr->p_memsz);
memset(baseAddress + phdr->p_filesz, 0, phdr->p_memsz - phdr->p_filesz);
}
// Read the segment into memory
if (lseek(fd, phdr->p_offset, SEEK_SET) < 0 ||
read(fd, baseAddress, phdr->p_filesz) != (ssize_t)phdr->p_filesz) {
seterror("Segment load failed.");
return false;
}
return true;
}
Elf32_Shdr * DLObject::loadSectionHeaders(int fd, Elf32_Ehdr *ehdr) {
Elf32_Shdr *shdr = NULL;
// Allocate memory for section headers
if (!(shdr = (Elf32_Shdr *)malloc(ehdr->e_shnum * sizeof(*shdr)))) {
seterror("Out of memory.");
return NULL;
}
// Read from file into section headers
if (lseek(fd, ehdr->e_shoff, SEEK_SET) < 0 ||
read(fd, shdr, ehdr->e_shnum * sizeof(*shdr)) !=
(ssize_t)(ehdr->e_shnum * sizeof(*shdr))) {
seterror("Section headers load failed.");
return NULL;
}
return shdr;
}
int DLObject::loadSymbolTable(int fd, Elf32_Ehdr *ehdr, Elf32_Shdr *shdr) {
// Loop over sections, looking for symbol table linked to a string table
for (int i = 0; i < ehdr->e_shnum; i++) {
//DBG("Section %d: type = %x, size = %x, entsize = %x, link = %x\n",
// i, shdr[i].sh_type, shdr[i].sh_size, shdr[i].sh_entsize, shdr[i].sh_link);
if (shdr[i].sh_type == SHT_SYMTAB &&
shdr[i].sh_entsize == sizeof(Elf32_Sym) &&
shdr[i].sh_link < ehdr->e_shnum &&
shdr[shdr[i].sh_link].sh_type == SHT_STRTAB &&
_symtab_sect < 0) {
_symtab_sect = i;
}
}
// Check for no symbol table
if (_symtab_sect < 0) {
seterror("No symbol table.");
return -1;
}
DBG("Symbol section at section %d, size %x\n", _symtab_sect, shdr[_symtab_sect].sh_size);
// Allocate memory for symbol table
if (!(_symtab = malloc(shdr[_symtab_sect].sh_size))) {
seterror("Out of memory.");
return -1;
}
// Read symbol table into memory
if (lseek(fd, shdr[_symtab_sect].sh_offset, SEEK_SET) < 0 ||
read(fd, _symtab, shdr[_symtab_sect].sh_size) !=
(ssize_t)shdr[_symtab_sect].sh_size) {
seterror("Symbol table load failed.");
return -1;
}
// Set number of symbols
_symbol_cnt = shdr[_symtab_sect].sh_size / sizeof(Elf32_Sym);
DBG("Loaded %d symbols.\n", _symbol_cnt);
return _symtab_sect;
}
bool DLObject::loadStringTable(int fd, Elf32_Shdr *shdr) {
int string_sect = shdr[_symtab_sect].sh_link;
// Allocate memory for string table
if (!(_strtab = (char *)malloc(shdr[string_sect].sh_size))) {
seterror("Out of memory.");
return false;
}
// Read string table into memory
if (lseek(fd, shdr[string_sect].sh_offset, SEEK_SET) < 0 ||
read(fd, _strtab, shdr[string_sect].sh_size) !=
(ssize_t)shdr[string_sect].sh_size) {
seterror("Symbol table strings load failed.");
return false;
}
return true;
}
void DLObject::relocateSymbols(Elf32_Addr offset, Elf32_Addr shortsOffset) {
int shortsCount = 0, othersCount = 0;
DBG("Relocating symbols by %x. Shorts offset=%x\n", offset, shortsOffset);
// Loop over symbols, add relocation offset
Elf32_Sym *s = (Elf32_Sym *)_symtab;
for (int c = _symbol_cnt; c--; s++) {
// Make sure we don't relocate special valued symbols
if (s->st_shndx < SHN_LOPROC) {
if (!ShortsMan.inGeneralSegment((char *)s->st_value)) {
othersCount++;
s->st_value += offset;
if (s->st_value < (Elf32_Addr)_segment || s->st_value > (Elf32_Addr)_segment + _segmentSize)
seterror("Symbol out of bounds! st_value = %x\n", s->st_value);
} else { // shorts section
shortsCount++;
s->st_value += shortsOffset;
if (!_shortsSegment->inSegment((char *)s->st_value))
seterror("Symbol out of bounds! st_value = %x\n", s->st_value);
}
}
}
DBG("Relocated %d short symbols, %d others.\n", shortsCount, othersCount);
}
bool DLObject::relocateRels(int fd, Elf32_Ehdr *ehdr, Elf32_Shdr *shdr) {
// Loop over sections, finding relocation sections
for (int i = 0; i < ehdr->e_shnum; i++) {
Elf32_Shdr *curShdr = &(shdr[i]);
//Elf32_Shdr *linkShdr = &(shdr[curShdr->sh_info]);
if (curShdr->sh_type == SHT_REL && // Check for a relocation section
curShdr->sh_entsize == sizeof(Elf32_Rel) && // Check for proper relocation size
(int)curShdr->sh_link == _symtab_sect && // Check that the sh_link connects to our symbol table
curShdr->sh_info < ehdr->e_shnum && // Check that the relocated section exists
(shdr[curShdr->sh_info].sh_flags & SHF_ALLOC)) { // Check if relocated section resides in memory
if (!ShortsMan.inGeneralSegment((char *)shdr[curShdr->sh_info].sh_addr)) { // regular segment
if (!relocate(fd, curShdr->sh_offset, curShdr->sh_size, _segment)) {
return false;
}
} else { // In Shorts segment
if (!relocate(fd, curShdr->sh_offset, curShdr->sh_size, (void *)_shortsSegment->getOffset())) {
return false;
}
}
}
}
return true;
}
bool DLObject::load(int fd) {
fprintf(stderr, "In DLObject::load\n");
Elf32_Ehdr ehdr; // ELF header
Elf32_Phdr phdr; // Program header
Elf32_Shdr *shdr; // Section header
bool ret = true;
if (readElfHeader(fd, &ehdr) == false) {
return false;
}
for (int i = 0; i < ehdr.e_phnum; i++) { // Load our 2 segments
fprintf(stderr, "Loading segment %d\n", i);
if (readProgramHeaders(fd, &ehdr, &phdr, i) == false)
return false;
if (!loadSegment(fd, &phdr))
return false;
}
if ((shdr = loadSectionHeaders(fd, &ehdr)) == NULL)
ret = false;
if (ret && ((_symtab_sect = loadSymbolTable(fd, &ehdr, shdr)) < 0))
ret = false;
if (ret && (loadStringTable(fd, shdr) == false))
ret = false;
if (ret)
relocateSymbols((Elf32_Addr)_segment, _shortsSegment->getOffset()); // Offset by our segment allocated address
if (ret && (relocateRels(fd, &ehdr, shdr) == false))
ret = false;
free(shdr);
return ret;
}
bool DLObject::open(const char *path) {
int fd;
void *ctors_start, *ctors_end;
DBG("open(\"%s\")\n", path);
// Get the address of the global pointer
_gpVal = (unsigned int) & _gp;
DBG("_gpVal is %x\n", _gpVal);
PowerMan.beginCriticalSection();
if ((fd = ::open(path, O_RDONLY)) < 0) {
seterror("%s not found.", path);
return false;
}
// Try to load and relocate
if (!load(fd)) {
::close(fd);
unload();
return false;
}
::close(fd);
PowerMan.endCriticalSection();
// flush data cache
sceKernelDcacheWritebackAll();
// Get the symbols for the global constructors and destructors
ctors_start = symbol("___plugin_ctors");
ctors_end = symbol("___plugin_ctors_end");
_dtors_start = symbol("___plugin_dtors");
_dtors_end = symbol("___plugin_dtors_end");
if (ctors_start == NULL || ctors_end == NULL || _dtors_start == NULL ||
_dtors_end == NULL) {
seterror("Missing ctors/dtors.");
_dtors_start = _dtors_end = NULL;
unload();
return false;
}
DBG("Calling constructors.\n");
for (void (**f)(void) = (void (**)(void))ctors_start; f != ctors_end; f++)
(**f)();
DBG("%s opened ok.\n", path);
return true;
}
bool DLObject::close() {
if (_dtors_start != NULL && _dtors_end != NULL)
for (void (**f)(void) = (void (**)(void))_dtors_start; f != _dtors_end; f++)
(**f)();
_dtors_start = _dtors_end = NULL;
unload();
return true;
}
void *DLObject::symbol(const char *name) {
DBG("symbol(\"%s\")\n", name);
if (_symtab == NULL || _strtab == NULL || _symbol_cnt < 1) {
seterror("No symbol table loaded.");
return NULL;
}
Elf32_Sym *s = (Elf32_Sym *)_symtab;
for (int c = _symbol_cnt; c--; s++) {
// We can only import symbols that are global or weak in the plugin
if ((SYM_BIND(s->st_info) == STB_GLOBAL || SYM_BIND(s->st_info) == STB_WEAK) &&
/*_strtab[s->st_name] == '_' && */ // Try to make this more efficient
!strcmp(name, _strtab + s->st_name)) {
// We found the symbol
DBG("=> %p\n", (void*)s->st_value);
return (void*)s->st_value;
}
}
seterror("Symbol \"%s\" not found.", name);
return NULL;
}
ShortSegmentManager::ShortSegmentManager() {
_shortsStart = &__plugin_hole_start ;
_shortsEnd = &__plugin_hole_end;
}
ShortSegmentManager::Segment *ShortSegmentManager::newSegment(int 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 ((int)(currAddress - 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) {
seterror("Error. No space in shorts segment for %x bytes. Last address is %p, max address is %p.\n",
size, lastAddress, _shortsEnd);
return NULL;
}
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);
DBG("Shorts segment size %x allocated. End = %p. Remaining space = %x. Highest so far is %p.\n",
size, lastAddress + size, _shortsEnd - _list.back()->getEnd(), _highestAddress);
return seg;
}
void ShortSegmentManager::deleteSegment(ShortSegmentManager::Segment *seg) {
DBG("Deleting shorts segment from %p to %p.\n\n", seg->getStart(), seg->getEnd());
_list.remove(seg);
delete seg;
}
static char dlerr[MAXDLERRLEN];
void *dlopen(const char *filename, int flags) {
DLObject *obj = new DLObject(dlerr);
if (obj->open(filename))
return (void *)obj;
delete obj;
return NULL;
}
int dlclose(void *handle) {
DLObject *obj = (DLObject *)handle;
if (obj == NULL) {
strcpy(dlerr, "Handle is NULL.");
return -1;
}
if (obj->close()) {
delete obj;
return 0;
}
return -1;
}
void *dlsym(void *handle, const char *symbol) {
if (handle == NULL) {
strcpy(dlerr, "Handle is NULL.");
return NULL;
}
return ((DLObject *)handle)->symbol(symbol);
}
const char *dlerror() {
return dlerr;
}
void dlforgetsyms(void *handle) {
if (handle != NULL)
((DLObject *)handle)->discard_symtab();
}
#endif /* DYNAMIC_MODULES && __PS2__ */
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