X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=gdb%2Fauxv.c;h=8710d2f0a10d719048220f26923bd6f58195d8c6;hb=cbda93a56a0af8d7787ff091caad64af1b2bd085;hp=afc7fdd46d3c1b7c36dcf76050a9b9c0a163d8b6;hpb=ffe5a37e17da959d4c4e43b33f23b9548ac6fb27;p=platform%2Fupstream%2Fbinutils.git

diff --git a/gdb/auxv.c b/gdb/auxv.c
index afc7fdd..8710d2f 100644
--- a/gdb/auxv.c
+++ b/gdb/auxv.c
@@ -1,6 +1,6 @@
 /* Auxiliary vector support for GDB, the GNU debugger.
 
-   Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+   Copyright (C) 2004-2014 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -23,7 +23,10 @@
 #include "command.h"
 #include "inferior.h"
 #include "valprint.h"
-#include "gdb_assert.h"
+#include "gdbcore.h"
+#include "observer.h"
+#include "filestuff.h"
+#include "objfiles.h"
 
 #include "auxv.h"
 #include "elf/common.h"
@@ -32,46 +35,219 @@
 #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.  */
+/* Implement the to_xfer_partial target_ops method.  This function
+   handles access via /proc/PID/auxv, which is a common method for
+   native targets.  */
 
-LONGEST
-procfs_xfer_auxv (struct target_ops *ops,
-		  int /* enum target_object */ object,
-		  const char *annex,
-		  gdb_byte *readbuf,
+static enum target_xfer_status
+procfs_xfer_auxv (gdb_byte *readbuf,
 		  const gdb_byte *writebuf,
 		  ULONGEST offset,
-		  LONGEST len)
+		  ULONGEST len,
+		  ULONGEST *xfered_len)
 {
   char *pathname;
   int fd;
-  LONGEST n;
+  ssize_t l;
 
-  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);
+  pathname = xstrprintf ("/proc/%d/auxv", ptid_get_pid (inferior_ptid));
+  fd = gdb_open_cloexec (pathname, writebuf != NULL ? O_WRONLY : O_RDONLY, 0);
   xfree (pathname);
   if (fd < 0)
-    return -1;
+    return TARGET_XFER_E_IO;
 
   if (offset != (ULONGEST) 0
       && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
-    n = -1;
+    l = -1;
   else if (readbuf != NULL)
-    n = read (fd, readbuf, len);
+    l = read (fd, readbuf, (size_t) len);
   else
-    n = write (fd, writebuf, len);
+    l = write (fd, writebuf, (size_t) len);
 
   (void) close (fd);
 
-  return n;
+  if (l < 0)
+    return TARGET_XFER_E_IO;
+  else if (l == 0)
+    return TARGET_XFER_EOF;
+  else
+    {
+      *xfered_len = (ULONGEST) l;
+      return TARGET_XFER_OK;
+    }
+}
+
+/* This function handles access via ld.so's symbol `_dl_auxv'.  */
+
+static enum target_xfer_status
+ld_so_xfer_auxv (gdb_byte *readbuf,
+		 const gdb_byte *writebuf,
+		 ULONGEST offset,
+		 ULONGEST len, ULONGEST *xfered_len)
+{
+  struct bound_minimal_symbol msym;
+  CORE_ADDR data_address, pointer_address;
+  struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr;
+  size_t ptr_size = TYPE_LENGTH (ptr_type);
+  size_t auxv_pair_size = 2 * ptr_size;
+  gdb_byte *ptr_buf = alloca (ptr_size);
+  LONGEST retval;
+  size_t block;
+
+  msym = lookup_minimal_symbol ("_dl_auxv", NULL, NULL);
+  if (msym.minsym == NULL)
+    return TARGET_XFER_E_IO;
+
+  if (MSYMBOL_SIZE (msym.minsym) != ptr_size)
+    return TARGET_XFER_E_IO;
+
+  /* POINTER_ADDRESS is a location where the `_dl_auxv' variable
+     resides.  DATA_ADDRESS is the inferior value present in
+     `_dl_auxv', therefore the real inferior AUXV address.  */
+
+  pointer_address = BMSYMBOL_VALUE_ADDRESS (msym);
+
+  /* The location of the _dl_auxv symbol may no longer be correct if
+     ld.so runs at a different address than the one present in the
+     file.  This is very common case - for unprelinked ld.so or with a
+     PIE executable.  PIE executable forces random address even for
+     libraries already being prelinked to some address.  PIE
+     executables themselves are never prelinked even on prelinked
+     systems.  Prelinking of a PIE executable would block their
+     purpose of randomizing load of everything including the
+     executable.
+
+     If the memory read fails, return -1 to fallback on another
+     mechanism for retrieving the AUXV.
+
+     In most cases of a PIE running under valgrind there is no way to
+     find out the base addresses of any of ld.so, executable or AUXV
+     as everything is randomized and /proc information is not relevant
+     for the virtual executable running under valgrind.  We think that
+     we might need a valgrind extension to make it work.  This is PR
+     11440.  */
+
+  if (target_read_memory (pointer_address, ptr_buf, ptr_size) != 0)
+    return TARGET_XFER_E_IO;
+
+  data_address = extract_typed_address (ptr_buf, ptr_type);
+
+  /* Possibly still not initialized such as during an inferior
+     startup.  */
+  if (data_address == 0)
+    return TARGET_XFER_E_IO;
+
+  data_address += offset;
+
+  if (writebuf != NULL)
+    {
+      if (target_write_memory (data_address, writebuf, len) == 0)
+	{
+	  *xfered_len = (ULONGEST) len;
+	  return TARGET_XFER_OK;
+	}
+      else
+	return TARGET_XFER_E_IO;
+    }
+
+  /* Stop if trying to read past the existing AUXV block.  The final
+     AT_NULL was already returned before.  */
+
+  if (offset >= auxv_pair_size)
+    {
+      if (target_read_memory (data_address - auxv_pair_size, ptr_buf,
+			      ptr_size) != 0)
+	return TARGET_XFER_E_IO;
+
+      if (extract_typed_address (ptr_buf, ptr_type) == AT_NULL)
+	return TARGET_XFER_EOF;
+    }
+
+  retval = 0;
+  block = 0x400;
+  gdb_assert (block % auxv_pair_size == 0);
+
+  while (len > 0)
+    {
+      if (block > len)
+	block = len;
+
+      /* Reading sizes smaller than AUXV_PAIR_SIZE is not supported.
+	 Tails unaligned to AUXV_PAIR_SIZE will not be read during a
+	 call (they should be completed during next read with
+	 new/extended buffer).  */
+
+      block &= -auxv_pair_size;
+      if (block == 0)
+	break;
+
+      if (target_read_memory (data_address, readbuf, block) != 0)
+	{
+	  if (block <= auxv_pair_size)
+	    break;
+
+	  block = auxv_pair_size;
+	  continue;
+	}
+
+      data_address += block;
+      len -= block;
+
+      /* Check terminal AT_NULL.  This function is being called
+         indefinitely being extended its READBUF until it returns EOF
+         (0).  */
+
+      while (block >= auxv_pair_size)
+	{
+	  retval += auxv_pair_size;
+
+	  if (extract_typed_address (readbuf, ptr_type) == AT_NULL)
+	    {
+	      *xfered_len = (ULONGEST) retval;
+	      return TARGET_XFER_OK;
+	    }
+
+	  readbuf += auxv_pair_size;
+	  block -= auxv_pair_size;
+	}
+    }
+
+  *xfered_len = (ULONGEST) retval;
+  return TARGET_XFER_OK;
+}
+
+/* Implement the to_xfer_partial target_ops method for
+   TARGET_OBJECT_AUXV.  It handles access to AUXV.  */
+
+enum target_xfer_status
+memory_xfer_auxv (struct target_ops *ops,
+		  enum target_object object,
+		  const char *annex,
+		  gdb_byte *readbuf,
+		  const gdb_byte *writebuf,
+		  ULONGEST offset,
+		  ULONGEST len, ULONGEST *xfered_len)
+{
+  gdb_assert (object == TARGET_OBJECT_AUXV);
+  gdb_assert (readbuf || writebuf);
+
+   /* ld_so_xfer_auxv is the only function safe for virtual
+      executables being executed by valgrind's memcheck.  Using
+      ld_so_xfer_auxv during inferior startup is problematic, because
+      ld.so symbol tables have not yet been relocated.  So GDB uses
+      this function only when attaching to a process.
+      */
+
+  if (current_inferior ()->attach_flag != 0)
+    {
+      enum target_xfer_status ret;
+
+      ret = ld_so_xfer_auxv (readbuf, writebuf, offset, len, xfered_len);
+      if (ret != TARGET_XFER_E_IO)
+	return ret;
+    }
+
+  return procfs_xfer_auxv (readbuf, writebuf, offset, len, xfered_len);
 }
 
 /* Read one auxv entry from *READPTR, not reading locations >= ENDPTR.
@@ -82,8 +258,9 @@ int
 default_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
 		   gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
 {
-  const int sizeof_auxv_field = gdbarch_ptr_bit (target_gdbarch)
+  const int sizeof_auxv_field = gdbarch_ptr_bit (target_gdbarch ())
 				/ TARGET_CHAR_BIT;
+  const enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
   gdb_byte *ptr = *readptr;
 
   if (endptr == ptr)
@@ -92,9 +269,9 @@ default_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
   if (endptr - ptr < sizeof_auxv_field * 2)
     return -1;
 
-  *typep = extract_unsigned_integer (ptr, sizeof_auxv_field);
+  *typep = extract_unsigned_integer (ptr, sizeof_auxv_field, byte_order);
   ptr += sizeof_auxv_field;
-  *valp = extract_unsigned_integer (ptr, sizeof_auxv_field);
+  *valp = extract_unsigned_integer (ptr, sizeof_auxv_field, byte_order);
   ptr += sizeof_auxv_field;
 
   *readptr = ptr;
@@ -109,12 +286,85 @@ int
 target_auxv_parse (struct target_ops *ops, gdb_byte **readptr,
                   gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp)
 {
-  struct target_ops *t;
-  for (t = ops; t != NULL; t = t->beneath)
-    if (t->to_auxv_parse != NULL)
-      return t->to_auxv_parse (t, readptr, endptr, typep, valp);
-  
-  return default_auxv_parse (ops, readptr, endptr, typep, valp);
+  struct gdbarch *gdbarch = target_gdbarch();
+
+  if (gdbarch_auxv_parse_p (gdbarch))
+    return gdbarch_auxv_parse (gdbarch, readptr, endptr, typep, valp);
+
+  return current_target.to_auxv_parse (&current_target, readptr, endptr,
+				       typep, valp);
+}
+
+
+/* Per-inferior data key for auxv.  */
+static const struct inferior_data *auxv_inferior_data;
+
+/*  Auxiliary Vector information structure.  This is used by GDB
+    for caching purposes for each inferior.  This helps reduce the
+    overhead of transfering data from a remote target to the local host.  */
+struct auxv_info
+{
+  LONGEST length;
+  gdb_byte *data;
+};
+
+/* Handles the cleanup of the auxv cache for inferior INF.  ARG is ignored.
+   Frees whatever allocated space there is to be freed and sets INF's auxv cache
+   data pointer to NULL.
+
+   This function is called when the following events occur: inferior_appeared,
+   inferior_exit and executable_changed.  */
+
+static void
+auxv_inferior_data_cleanup (struct inferior *inf, void *arg)
+{
+  struct auxv_info *info;
+
+  info = inferior_data (inf, auxv_inferior_data);
+  if (info != NULL)
+    {
+      xfree (info->data);
+      xfree (info);
+      set_inferior_data (inf, auxv_inferior_data, NULL);
+    }
+}
+
+/* Invalidate INF's auxv cache.  */
+
+static void
+invalidate_auxv_cache_inf (struct inferior *inf)
+{
+  auxv_inferior_data_cleanup (inf, NULL);
+}
+
+/* Invalidate current inferior's auxv cache.  */
+
+static void
+invalidate_auxv_cache (void)
+{
+  invalidate_auxv_cache_inf (current_inferior ());
+}
+
+/* Fetch the auxv object from inferior INF.  If auxv is cached already,
+   return a pointer to the cache.  If not, fetch the auxv object from the
+   target and cache it.  This function always returns a valid INFO pointer.  */
+
+static struct auxv_info *
+get_auxv_inferior_data (struct target_ops *ops)
+{
+  struct auxv_info *info;
+  struct inferior *inf = current_inferior ();
+
+  info = inferior_data (inf, auxv_inferior_data);
+  if (info == NULL)
+    {
+      info = XCNEW (struct auxv_info);
+      info->length = target_read_alloc (ops, TARGET_OBJECT_AUXV,
+					NULL, &info->data);
+      set_inferior_data (inf, auxv_inferior_data, info);
+    }
+
+  return info;
 }
 
 /* Extract the auxiliary vector entry with a_type matching MATCH.
@@ -126,29 +376,30 @@ 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;
+  gdb_byte *ptr;
+  struct auxv_info *info;
+
+  info = get_auxv_inferior_data (ops);
+
+  data = info->data;
+  ptr = data;
 
-  if (n <= 0)
-    return n;
+  if (info->length <= 0)
+    return info->length;
 
   while (1)
-    switch (target_auxv_parse (ops, &ptr, data + n, &type, &val))
+    switch (target_auxv_parse (ops, &ptr, data + info->length, &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;
       }
 
@@ -156,23 +407,25 @@ target_auxv_search (struct target_ops *ops, CORE_ADDR match, CORE_ADDR *valp)
 }
 
 
-/* Print the contents of the target's AUXV on the specified file. */
+/* 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;
+  gdb_byte *ptr;
+  struct auxv_info *info;
   int ents = 0;
 
-  if (len <= 0)
-    return len;
+  info = get_auxv_inferior_data (ops);
 
-  while (target_auxv_parse (ops, &ptr, data + len, &type, &val) > 0)
+  data = info->data;
+  ptr = data;
+  if (info->length <= 0)
+    return info->length;
+
+  while (target_auxv_parse (ops, &ptr, data + info->length, &type, &val) > 0)
     {
-      extern int addressprint;
       const char *name = "???";
       const char *description = "";
       enum { dec, hex, str } flavor = hex;
@@ -204,9 +457,17 @@ fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 	  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_BASE_PLATFORM, _("String identifying base platform"), str);
+	  TAG (AT_RANDOM, _("Address of 16 random bytes"), hex);
+	  TAG (AT_HWCAP2, _("Extension of AT_HWCAP"), hex);
+	  TAG (AT_EXECFN, _("File name of executable"), str);
+	  TAG (AT_SECURE, _("Boolean, was exec setuid-like?"), 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_L1I_CACHESHAPE, _("L1 Instruction cache information"), hex);
+	  TAG (AT_L1D_CACHESHAPE, _("L1 Data cache information"), hex);
+	  TAG (AT_L2_CACHESHAPE, _("L2 cache information"), hex);
+	  TAG (AT_L3_CACHESHAPE, _("L3 cache information"), hex);
 	  TAG (AT_SUN_UID, _("Effective user ID"), dec);
 	  TAG (AT_SUN_RUID, _("Real user ID"), dec);
 	  TAG (AT_SUN_GID, _("Effective group ID"), dec);
@@ -237,13 +498,19 @@ fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 	  fprintf_filtered (file, "%s\n", plongest (val));
 	  break;
 	case hex:
-	  fprintf_filtered (file, "0x%s\n", paddr_nz (val));
+	  fprintf_filtered (file, "%s\n", paddress (target_gdbarch (), 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");
+	  {
+	    struct value_print_options opts;
+
+	    get_user_print_options (&opts);
+	    if (opts.addressprint)
+	      fprintf_filtered (file, "%s ", paddress (target_gdbarch (), val));
+	    val_print_string (builtin_type (target_gdbarch ())->builtin_char,
+			      NULL, val, -1, file, &opts);
+	    fprintf_filtered (file, "\n");
+	  }
 	  break;
 	}
       ++ents;
@@ -251,8 +518,6 @@ fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 	break;
     }
 
-  xfree (data);
-
   return ents;
 }
 
@@ -264,6 +529,7 @@ info_auxv_command (char *cmd, int from_tty)
   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)
@@ -280,4 +546,13 @@ _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."));
+
+  /* Set an auxv cache per-inferior.  */
+  auxv_inferior_data
+    = register_inferior_data_with_cleanup (NULL, auxv_inferior_data_cleanup);
+
+  /* Observers used to invalidate the auxv cache when needed.  */
+  observer_attach_inferior_exit (invalidate_auxv_cache_inf);
+  observer_attach_inferior_appeared (invalidate_auxv_cache_inf);
+  observer_attach_executable_changed (invalidate_auxv_cache);
 }