diff options
Diffstat (limited to 'src/core/elf/elf_reader.cpp')
| -rw-r--r-- | src/core/elf/elf_reader.cpp | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/src/core/elf/elf_reader.cpp b/src/core/elf/elf_reader.cpp new file mode 100644 index 00000000..aef7c13e --- /dev/null +++ b/src/core/elf/elf_reader.cpp @@ -0,0 +1,239 @@ +// Copyright 2013 Dolphin Emulator Project +// Licensed under GPLv2 +// Refer to the license.txt file included. + +#include <string> + +#include "common.h" +#include "mem_map.h" + +#include "elf/elf_reader.h" +//#include "Core/Debugger/Debugger_SymbolMap.h" +//#include "Core/HW/Memmap.h" +//#include "Core/PowerPC/PPCSymbolDB.h" + +//void bswap(Elf32_Word &w) {w = Common::swap32(w);} +//void bswap(Elf32_Half &w) {w = Common::swap16(w);} + +#define bswap(w) w // Dirty bswap disable for now... 3DS is little endian, anyway + +static void byteswapHeader(Elf32_Ehdr &ELF_H) +{ + bswap(ELF_H.e_type); + bswap(ELF_H.e_machine); + bswap(ELF_H.e_ehsize); + bswap(ELF_H.e_phentsize); + bswap(ELF_H.e_phnum); + bswap(ELF_H.e_shentsize); + bswap(ELF_H.e_shnum); + bswap(ELF_H.e_shstrndx); + bswap(ELF_H.e_version); + bswap(ELF_H.e_entry); + bswap(ELF_H.e_phoff); + bswap(ELF_H.e_shoff); + bswap(ELF_H.e_flags); +} + +static void byteswapSegment(Elf32_Phdr &sec) +{ + bswap(sec.p_align); + bswap(sec.p_filesz); + bswap(sec.p_flags); + bswap(sec.p_memsz); + bswap(sec.p_offset); + bswap(sec.p_paddr); + bswap(sec.p_vaddr); + bswap(sec.p_type); +} + +static void byteswapSection(Elf32_Shdr &sec) +{ + bswap(sec.sh_addr); + bswap(sec.sh_addralign); + bswap(sec.sh_entsize); + bswap(sec.sh_flags); + bswap(sec.sh_info); + bswap(sec.sh_link); + bswap(sec.sh_name); + bswap(sec.sh_offset); + bswap(sec.sh_size); + bswap(sec.sh_type); +} + +ElfReader::ElfReader(void *ptr) +{ + base = (char*)ptr; + base32 = (u32 *)ptr; + header = (Elf32_Ehdr*)ptr; + byteswapHeader(*header); + + segments = (Elf32_Phdr *)(base + header->e_phoff); + sections = (Elf32_Shdr *)(base + header->e_shoff); + + //for (int i = 0; i < GetNumSegments(); i++) + //{ + // byteswapSegment(segments[i]); + //} + + //for (int i = 0; i < GetNumSections(); i++) + //{ + // byteswapSection(sections[i]); + //} + entryPoint = header->e_entry; +} + +const char *ElfReader::GetSectionName(int section) const +{ + if (sections[section].sh_type == SHT_NULL) + return nullptr; + + int nameOffset = sections[section].sh_name; + char *ptr = (char*)GetSectionDataPtr(header->e_shstrndx); + + if (ptr) + return ptr + nameOffset; + else + return nullptr; +} + +bool ElfReader::LoadInto(u32 vaddr) +{ + DEBUG_LOG(MASTER_LOG,"String section: %i", header->e_shstrndx); + +// sectionOffsets = new u32[GetNumSections()]; +// sectionAddrs = new u32[GetNumSections()]; + + // Should we relocate? + bRelocate = (header->e_type != ET_EXEC); + + if (bRelocate) + { + DEBUG_LOG(MASTER_LOG,"Relocatable module"); + entryPoint += vaddr; + } + else + { + DEBUG_LOG(MASTER_LOG,"Prerelocated executable"); + } + + INFO_LOG(MASTER_LOG,"%i segments:", header->e_phnum); + + // First pass : Get the bits into RAM + u32 segmentVAddr[32]; + + u32 baseAddress = bRelocate?vaddr:0; + + for (int i = 0; i < header->e_phnum; i++) + { + Elf32_Phdr *p = segments + i; + + INFO_LOG(MASTER_LOG, "Type: %i Vaddr: %08x Filesz: %i Memsz: %i ", p->p_type, p->p_vaddr, p->p_filesz, p->p_memsz); + + if (p->p_type == PT_LOAD) + { + segmentVAddr[i] = baseAddress + p->p_vaddr; + u32 writeAddr = segmentVAddr[i]; + + const u8 *src = GetSegmentPtr(i); + u8 *dst = Memory::GetPointer(writeAddr); + u32 srcSize = p->p_filesz; + u32 dstSize = p->p_memsz; + u32 *s = (u32*)src; + u32 *d = (u32*)dst; + for (int j = 0; j < (int)(srcSize + 3) / 4; j++) + { + *d++ = /*_byteswap_ulong*/(*s++); + } + if (srcSize < dstSize) + { + //memset(dst + srcSize, 0, dstSize-srcSize); //zero out bss + } + INFO_LOG(MASTER_LOG,"Loadable Segment Copied to %08x, size %08x", writeAddr, p->p_memsz); + } + } + + /* + LOG(MASTER_LOG,"%i sections:", header->e_shnum); + + for (int i=0; i<GetNumSections(); i++) + { + Elf32_Shdr *s = §ions[i]; + const char *name = GetSectionName(i); + + u32 writeAddr = s->sh_addr + baseAddress; + sectionOffsets[i] = writeAddr - vaddr; + sectionAddrs[i] = writeAddr; + + if (s->sh_flags & SHF_ALLOC) + { + LOG(MASTER_LOG,"Data Section found: %s Sitting at %08x, size %08x", name, writeAddr, s->sh_size); + + } + else + { + LOG(MASTER_LOG,"NonData Section found: %s Ignoring (size=%08x) (flags=%08x)", name, s->sh_size, s->sh_flags); + } + } +*/ + INFO_LOG(MASTER_LOG,"Done loading."); + return true; +} + +SectionID ElfReader::GetSectionByName(const char *name, int firstSection) const +{ + for (int i = firstSection; i < header->e_shnum; i++) + { + const char *secname = GetSectionName(i); + + if (secname != nullptr && strcmp(name, secname) == 0) + return i; + } + return -1; +} + +/* TODO(bunnei): The following is verbatim from Dolphin - needs to be updated for this project: + +bool ElfReader::LoadSymbols() +{ + bool hasSymbols = false; + SectionID sec = GetSectionByName(".symtab"); + if (sec != -1) + { + int stringSection = sections[sec].sh_link; + const char *stringBase = (const char *)GetSectionDataPtr(stringSection); + + //We have a symbol table! + Elf32_Sym *symtab = (Elf32_Sym *)(GetSectionDataPtr(sec)); + int numSymbols = sections[sec].sh_size / sizeof(Elf32_Sym); + for (int sym = 0; sym < numSymbols; sym++) + { + int size = Common::swap32(symtab[sym].st_size); + if (size == 0) + continue; + + // int bind = symtab[sym].st_info >> 4; + int type = symtab[sym].st_info & 0xF; + int sectionIndex = Common::swap16(symtab[sym].st_shndx); + int value = Common::swap32(symtab[sym].st_value); + const char *name = stringBase + Common::swap32(symtab[sym].st_name); + if (bRelocate) + value += sectionAddrs[sectionIndex]; + + int symtype = Symbol::SYMBOL_DATA; + switch (type) + { + case STT_OBJECT: + symtype = Symbol::SYMBOL_DATA; break; + case STT_FUNC: + symtype = Symbol::SYMBOL_FUNCTION; break; + default: + continue; + } + g_symbolDB.AddKnownSymbol(value, size, name, symtype); + hasSymbols = true; + } + } + g_symbolDB.Index(); + return hasSymbols; +} +*/ |