Subversion Repositories openrisc_2011-10-31

/* Auxiliary vector support for GDB, the GNU debugger.

   Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

   This file is part of GDB.

   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 3 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, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"

#include "target.h"

#include "gdbtypes.h"

#include "command.h"

#include "inferior.h"

#include "valprint.h"

#include "gdb_assert.h"

#include "auxv.h"

#include "elf/common.h"

#include <unistd.h>

#include <fcntl.h>

/* This function is called like a to_xfer_partial hook,

   but must be called with TARGET_OBJECT_AUXV.

   It handles access via /proc/PID/auxv, which is the common method.

   This function is appropriate for doing:

           #define NATIVE_XFER_AUXV     procfs_xfer_auxv

   for a native target that uses inftarg.c's child_xfer_partial hook.  */

LONGEST

procfs_xfer_auxv (struct target_ops *ops,

                  int /* enum target_object */ object,

                  const char *annex,

                  gdb_byte *readbuf,

                  const gdb_byte *writebuf,

                  ULONGEST offset,

                  LONGEST len)

{

  char *pathname;

  int fd;

  LONGEST n;

  gdb_assert (object == TARGET_OBJECT_AUXV);

  gdb_assert (readbuf || writebuf);

  pathname = xstrprintf ("/proc/%d/auxv", PIDGET (inferior_ptid));

  fd = open (pathname, writebuf != NULL ? O_WRONLY : O_RDONLY);

  xfree (pathname);

  if (fd < 0)

    return -1;

  if (offset != (ULONGEST) 0

      && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)

    n = -1;

  else if (readbuf != NULL)

    n = read (fd, readbuf, len);

  else

    n = write (fd, writebuf, len);

  (void) close (fd);

  return n;

}

/* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.

   Return 0 if *READPTR is already at the end of the buffer.

   Return -1 if there is insufficient buffer for a whole entry.

   Return 1 if an entry was read into *TYPEP and *VALP.  */

int

target_auxv_parse (struct target_ops *ops, gdb_byte **readptr,

                   gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)

{

  const int sizeof_auxv_field = TYPE_LENGTH (builtin_type_void_data_ptr);

  gdb_byte *ptr = *readptr;

  if (endptr == ptr)

    return 0;

  if (endptr - ptr < sizeof_auxv_field * 2)

    return -1;

  *typep = extract_unsigned_integer (ptr, sizeof_auxv_field);

  ptr += sizeof_auxv_field;

  *valp = extract_unsigned_integer (ptr, sizeof_auxv_field);

  ptr += sizeof_auxv_field;

  *readptr = ptr;

  return 1;

}

/* Extract the auxiliary vector entry with a_type matching MATCH.

   Return zero if no such entry was found, or -1 if there was

   an error getting the information.  On success, return 1 after

   storing the entry's value field in *VALP.  */

int

target_auxv_search (struct target_ops *ops, CORE_ADDR match, CORE_ADDR *valp)

{

  CORE_ADDR type, val;

  gdb_byte *data;

  LONGEST n = target_read_alloc (ops, TARGET_OBJECT_AUXV, NULL, &data);

  gdb_byte *ptr = data;

  int ents = 0;

  if (n <= 0)

    return n;

  while (1)

    switch (target_auxv_parse (ops, &ptr, data + n, &type, &val))

      {

      case 1:                   /* Here's an entry, check it.  */

        if (type == match)

          {

            xfree (data);

            *valp = val;

            return 1;

          }

        break;

      case 0:                    /* End of the vector.  */

        xfree (data);

        return 0;

      default:                  /* Bogosity.  */

        xfree (data);

        return -1;

      }

  /*NOTREACHED*/

}

/* Print the contents of the target's AUXV on the specified file. */

int

fprint_target_auxv (struct ui_file *file, struct target_ops *ops)

{

  CORE_ADDR type, val;

  gdb_byte *data;

  LONGEST len = target_read_alloc (ops, TARGET_OBJECT_AUXV, NULL,

                                   &data);

  gdb_byte *ptr = data;

  int ents = 0;

  if (len <= 0)

    return len;

  while (target_auxv_parse (ops, &ptr, data + len, &type, &val) > 0)

    {

      extern int addressprint;

      const char *name = "???";

      const char *description = "";

      enum { dec, hex, str } flavor = hex;

      switch (type)

        {

#define TAG(tag, text, kind) \

        case tag: name = #tag; description = text; flavor = kind; break

          TAG (AT_NULL, _("End of vector"), hex);

          TAG (AT_IGNORE, _("Entry should be ignored"), hex);

          TAG (AT_EXECFD, _("File descriptor of program"), dec);

          TAG (AT_PHDR, _("Program headers for program"), hex);

          TAG (AT_PHENT, _("Size of program header entry"), dec);

          TAG (AT_PHNUM, _("Number of program headers"), dec);

          TAG (AT_PAGESZ, _("System page size"), dec);

          TAG (AT_BASE, _("Base address of interpreter"), hex);

          TAG (AT_FLAGS, _("Flags"), hex);

          TAG (AT_ENTRY, _("Entry point of program"), hex);

          TAG (AT_NOTELF, _("Program is not ELF"), dec);

          TAG (AT_UID, _("Real user ID"), dec);

          TAG (AT_EUID, _("Effective user ID"), dec);

          TAG (AT_GID, _("Real group ID"), dec);

          TAG (AT_EGID, _("Effective group ID"), dec);

          TAG (AT_CLKTCK, _("Frequency of times()"), dec);

          TAG (AT_PLATFORM, _("String identifying platform"), str);

          TAG (AT_HWCAP, _("Machine-dependent CPU capability hints"), hex);

          TAG (AT_FPUCW, _("Used FPU control word"), dec);

          TAG (AT_DCACHEBSIZE, _("Data cache block size"), dec);

          TAG (AT_ICACHEBSIZE, _("Instruction cache block size"), dec);

          TAG (AT_UCACHEBSIZE, _("Unified cache block size"), dec);

          TAG (AT_IGNOREPPC, _("Entry should be ignored"), dec);

          TAG (AT_SYSINFO, _("Special system info/entry points"), hex);

          TAG (AT_SYSINFO_EHDR, _("System-supplied DSO's ELF header"), hex);

          TAG (AT_SECURE, _("Boolean, was exec setuid-like?"), dec);

          TAG (AT_SUN_UID, _("Effective user ID"), dec);

          TAG (AT_SUN_RUID, _("Real user ID"), dec);

          TAG (AT_SUN_GID, _("Effective group ID"), dec);

          TAG (AT_SUN_RGID, _("Real group ID"), dec);

          TAG (AT_SUN_LDELF, _("Dynamic linker's ELF header"), hex);

          TAG (AT_SUN_LDSHDR, _("Dynamic linker's section headers"), hex);

          TAG (AT_SUN_LDNAME, _("String giving name of dynamic linker"), str);

          TAG (AT_SUN_LPAGESZ, _("Large pagesize"), dec);

          TAG (AT_SUN_PLATFORM, _("Platform name string"), str);

          TAG (AT_SUN_HWCAP, _("Machine-dependent CPU capability hints"), hex);

          TAG (AT_SUN_IFLUSH, _("Should flush icache?"), dec);

          TAG (AT_SUN_CPU, _("CPU name string"), str);

          TAG (AT_SUN_EMUL_ENTRY, _("COFF entry point address"), hex);

          TAG (AT_SUN_EMUL_EXECFD, _("COFF executable file descriptor"), dec);

          TAG (AT_SUN_EXECNAME,

               _("Canonicalized file name given to execve"), str);

          TAG (AT_SUN_MMU, _("String for name of MMU module"), str);

          TAG (AT_SUN_LDDATA, _("Dynamic linker's data segment address"), hex);

          TAG (AT_SUN_AUXFLAGS,

               _("AF_SUN_ flags passed from the kernel"), hex);

        }

      fprintf_filtered (file, "%-4s %-20s %-30s ",

                        paddr_d (type), name, description);

      switch (flavor)

        {

        case dec:

          fprintf_filtered (file, "%s\n", paddr_d (val));

          break;

        case hex:

          fprintf_filtered (file, "0x%s\n", paddr_nz (val));

          break;

        case str:

          if (addressprint)

            fprintf_filtered (file, "0x%s", paddr_nz (val));

          val_print_string (val, -1, 1, file);

          fprintf_filtered (file, "\n");

          break;

        }

      ++ents;

    }

  xfree (data);

  return ents;

}

static void

info_auxv_command (char *cmd, int from_tty)

{

  if (! target_has_stack)

    error (_("The program has no auxiliary information now."));

  else

    {

      int ents = fprint_target_auxv (gdb_stdout, &current_target);

      if (ents < 0)

        error (_("No auxiliary vector found, or failed reading it."));

      else if (ents == 0)

        error (_("Auxiliary vector is empty."));

    }

}

extern initialize_file_ftype _initialize_auxv; /* -Wmissing-prototypes; */

void

_initialize_auxv (void)

{

  add_info ("auxv", info_auxv_command,

            _("Display the inferior's auxiliary vector.\n\

This is information provided by the operating system at program startup."));

}