csdbg::symtab::symtab ( const i8 *  path, mem_addr_t  base = 0  )

explicit

Object constructor.

Parameters

[in]	path	the path of the objective code file
[in]	base	the load base address

Exceptions

std::bad_alloc
csdbg::exception

Definition at line 22 of file symtab.cpp.

References csdbg::util::dbg_info(), likely, m_base, m_path, m_table, and unlikely.

Referenced by clone().

                                             :
m_path(NULL),
m_base(base),
m_table(NULL)
{
  if ( unlikely(path == NULL) )
    throw exception("invalid argument: path (=%p)", path);

  m_path = new i8[strlen(path) + 1];
  strcpy(m_path, path);

  bfd *fd = NULL;
  asymbol **tbl = NULL;
  i8 *nm = NULL;
  symbol *sym = NULL;

  /* If an exception occurs, release resources and rethrow it */
  try {
    /* Open the binary file and obtain a descriptor (the bfd) */
    fd = bfd_openr(m_path, NULL);
    if ( unlikely(fd == NULL) ) {
      bfd_error bfd_errno = bfd_get_error();
      throw exception(
        "failed to open file '%s' (bfd errno %d - %s)",
        m_path,
        bfd_errno,
        bfd_errmsg(bfd_errno)
      );
    }

    /* Verify that the file contains objective code */
    if ( unlikely(!bfd_check_format(fd, bfd_object)) ) {
      bfd_error bfd_errno = bfd_get_error();
      throw exception(
        "failed to verify file '%s' (bfd errno %d - %s)",
        m_path,
        bfd_errno,
        bfd_errmsg(bfd_errno)
      );
    }

    /* Get the symbol table storage size */
    i32 sz = bfd_get_symtab_upper_bound(fd);
    if ( unlikely(sz == 0) )
      throw exception("file '%s' is stripped", m_path);

    else if ( unlikely(sz < 0) ) {
      bfd_error bfd_errno = bfd_get_error();
      throw exception(
        "failed to parse file '%s' (bfd errno %d - %s)",
        m_path,
        bfd_errno,
        bfd_errmsg(bfd_errno)
      );
    }

    /* Canonicalize the symbol table and get the symbol count */
    tbl = new asymbol*[sz];
    i32 cnt = bfd_canonicalize_symtab(fd, tbl);
    if ( unlikely(cnt == 0) )
      throw exception("file '%s' is stripped", m_path);

    else if ( unlikely(cnt < 0) ) {
      bfd_error bfd_errno = bfd_get_error();
      throw exception(
        "failed to canonicalize the symbol table of '%s' (bfd errno %d - %s)",
        m_path,
        bfd_errno,
        bfd_errmsg(bfd_errno)
      );
    }

    /* Traverse the symbol table, discard non function symbols */
    m_table = new chain<symbol>;
    for (i32 i = 0; likely(i < cnt); i++) {
      const asymbol *cur = tbl[i];

      /* If the entry is not in a code section */
      if ( likely((cur->section->flags & SEC_CODE) == 0) )
        continue;

      /* If the entry is not a function symbol */
      if ( likely((cur->flags & BSF_FUNCTION) == 0) )
        continue;

      /*
       * A symbol runtime address is the load address, plus the section virtual
       * memory address, plus the offset from the section base
       */
      mem_addr_t addr = m_base;
      addr += bfd_get_section_vma(fd, cur->section);
      addr += cur->value;

      /* Demangle and store the symbol */
      nm = abi::__cxa_demangle(cur->name, NULL, NULL, NULL);
      if ( likely(nm != NULL) ) {
        sym = new symbol(addr, nm);
        delete[] nm;
        nm = NULL;
      }
      else
        sym = new symbol(addr, cur->name);

      m_table->add(sym);
      sym = NULL;
    }

    delete[] tbl;
    bfd_close(fd);

#if CSDBG_DBG_LEVEL & CSDBG_DBGL_INFO
    util::dbg_info("loaded the symbol table of '%s'", m_path);
    util::dbg_info("  base address @ %p", m_base);
    util::dbg_info("  number of symbols: %d", cnt);
    util::dbg_info("  number of function symbols: %d", m_table->size());
#endif
  }

  catch (...) {
    delete[] m_path;
    delete[] tbl;
    delete[] nm;

    delete m_table;
    delete sym;

    m_path = NULL;
    m_table = NULL;

    if ( likely(fd != NULL) )
      bfd_close(fd);

    throw;
  }
}

Here is the call graph for this function:

Here is the caller graph for this function: