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/* General "disassemble this chunk" code. Used for debugging. */
#include "dis-asm.h"
#include "disas.h"
#include "elf.h"
#include <errno.h>
/* Filled in by elfload.c. Simplistic, but will do for now. */
unsigned int disas_num_syms;
void *disas_symtab;
const char *disas_strtab;
/* Get LENGTH bytes from info's buffer, at target address memaddr.
Transfer them to myaddr. */
int
buffer_read_memory (memaddr, myaddr, length, info)
bfd_vma memaddr;
bfd_byte *myaddr;
int length;
struct disassemble_info *info;
{
if (memaddr < info->buffer_vma
|| memaddr + length > info->buffer_vma + info->buffer_length)
/* Out of bounds. Use EIO because GDB uses it. */
return EIO;
memcpy (myaddr, info->buffer + (memaddr - info->buffer_vma), length);
return 0;
}
/* Print an error message. We can assume that this is in response to
an error return from buffer_read_memory. */
void
perror_memory (status, memaddr, info)
int status;
bfd_vma memaddr;
struct disassemble_info *info;
{
if (status != EIO)
/* Can't happen. */
(*info->fprintf_func) (info->stream, "Unknown error %d\n", status);
else
/* Actually, address between memaddr and memaddr + len was
out of bounds. */
(*info->fprintf_func) (info->stream,
"Address 0x%x is out of bounds.\n", memaddr);
}
/* This could be in a separate file, to save miniscule amounts of space
in statically linked executables. */
/* Just print the address is hex. This is included for completeness even
though both GDB and objdump provide their own (to print symbolic
addresses). */
void
generic_print_address (addr, info)
bfd_vma addr;
struct disassemble_info *info;
{
(*info->fprintf_func) (info->stream, "0x%x", addr);
}
/* Just return the given address. */
int
generic_symbol_at_address (addr, info)
bfd_vma addr;
struct disassemble_info * info;
{
return 1;
}
bfd_vma bfd_getl32 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0];
v |= (unsigned long) addr[1] << 8;
v |= (unsigned long) addr[2] << 16;
v |= (unsigned long) addr[3] << 24;
return (bfd_vma) v;
}
bfd_vma bfd_getb32 (const bfd_byte *addr)
{
unsigned long v;
v = (unsigned long) addr[0] << 24;
v |= (unsigned long) addr[1] << 16;
v |= (unsigned long) addr[2] << 8;
v |= (unsigned long) addr[3];
return (bfd_vma) v;
}
/* Disassemble this for me please... (debugging). */
void disas(FILE *out, void *code, unsigned long size, enum disas_type type)
{
uint8_t *pc;
int count;
struct disassemble_info disasm_info;
int (*print_insn)(bfd_vma pc, disassemble_info *info);
INIT_DISASSEMBLE_INFO(disasm_info, out, fprintf);
disasm_info.buffer = code;
disasm_info.buffer_vma = (unsigned long)code;
disasm_info.buffer_length = size;
if (type == DISAS_TARGET) {
#ifdef WORDS_BIGENDIAN
disasm_info.endian = BFD_ENDIAN_BIG;
#else
disasm_info.endian = BFD_ENDIAN_LITTLE;
#endif
#ifdef __i386__
disasm_info.mach = bfd_mach_i386_i386;
print_insn = print_insn_i386;
#elif defined(__powerpc__)
print_insn = print_insn_ppc;
#elif defined(__alpha__)
print_insn = print_insn_alpha;
#elif defined(__sparc__)
print_insn = print_insn_sparc;
#elif defined(__arm__)
print_insn = print_insn_arm;
#else
fprintf(out, "Asm output not supported on this arch\n");
return;
#endif
} else {
/* Currently only source supported in x86. */
disasm_info.endian = BFD_ENDIAN_LITTLE;
if (type == DISAS_I386_I386)
disasm_info.mach = bfd_mach_i386_i386;
else
disasm_info.mach = bfd_mach_i386_i8086;
print_insn = print_insn_i386;
}
for (pc = code; pc < (uint8_t *)code + size; pc += count) {
fprintf(out, "0x%08lx: ", (long)pc);
#ifdef __arm__
/* since data are included in the code, it is better to
display code data too */
if (type == DISAS_TARGET) {
fprintf(out, "%08x ", (int)bfd_getl32((const bfd_byte *)pc));
}
#endif
count = print_insn((unsigned long)pc, &disasm_info);
fprintf(out, "\n");
if (count < 0)
break;
}
}
/* Look up symbol for debugging purpose. Returns "" if unknown. */
const char *lookup_symbol(void *orig_addr)
{
unsigned int i;
/* Hack, because we know this is x86. */
Elf32_Sym *sym = disas_symtab;
for (i = 0; i < disas_num_syms; i++) {
if (sym[i].st_shndx == SHN_UNDEF
|| sym[i].st_shndx >= SHN_LORESERVE)
continue;
if (ELF_ST_TYPE(sym[i].st_info) != STT_FUNC)
continue;
if ((long)orig_addr >= sym[i].st_value
&& (long)orig_addr < sym[i].st_value + sym[i].st_size)
return disas_strtab + sym[i].st_name;
}
return "";
}
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