1 files changed, 79 insertions, 0 deletions
diff --git a/disas.c b/disas.c
new file mode 100644
index 000000000..d3dcdffd1
--- /dev/null
+++ b/disas.c
@@ -0,0 +1,79 @@
+/* General "disassemble this chunk" code.  Used for debugging. */
+#include "dis-asm.h"
+#include "disas.h"
+#include "elf.h"
+
+/* Filled in by elfload.c.  Simplistic, but will do for now. */
+unsigned int disas_num_syms;
+void *disas_symtab;
+const char *disas_strtab;
+
+/* 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;
+#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);
+	count = print_insn((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 "";
+}