2004-01-28 Roland McGrath <roland@redhat.com>

	* auxv.h: New file.
	* auxv.c: New file.
	* Makefile.in (auxv_h): New variable.
	(COMMON_OBS): Add auxv.o here.
	(auxv.o): New target.

1 files changed, 301 insertions, 0 deletions

diff --git a/gdb/auxv.c b/gdb/auxv.c
new file mode 100644
index 0000000..c28014c
--- /dev/null
+++ b/gdb/auxv.c
@@ -0,0 +1,301 @@
+/* Auxiliary vector support for GDB, the GNU debugger.
+
+   Copyright 2004 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 2 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#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,
+		  void *readbuf,
+		  const void *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 all the auxv data into a contiguous xmalloc'd buffer,
+   stored in *DATA.  Return the size in bytes of this data.
+   If zero, there is no data and *DATA is null.
+   if < 0, there was an error and *DATA is null.  */
+LONGEST
+target_auxv_read (struct target_ops *ops, char **data)
+{
+  size_t auxv_alloc = 512, auxv_pos = 0;
+  char *auxv = xmalloc (auxv_alloc);
+  int n;
+
+  while (1)
+    {
+      n = target_read_partial (ops, TARGET_OBJECT_AUXV,
+			       NULL, &auxv[auxv_pos], 0,
+			       auxv_alloc - auxv_pos);
+      if (n <= 0)
+	break;
+      auxv_pos += n;
+      if (auxv_pos < auxv_alloc) /* Read all there was.  */
+	break;
+      gdb_assert (auxv_pos == auxv_alloc);
+      auxv_alloc *= 2;
+      auxv = xrealloc (auxv, auxv_alloc);
+    }
+
+  if (auxv_pos == 0)
+    {
+      xfree (auxv);
+      *data = NULL;
+      return n;
+    }
+
+  *data = auxv;
+  return auxv_pos;
+}
+
+/* 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, char **readptr, char *endptr,
+		   CORE_ADDR *typep, CORE_ADDR *valp)
+{
+  const int sizeof_auxv_field = TYPE_LENGTH (builtin_type_void_data_ptr);
+  char *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;
+  char *data;
+  int n = target_auxv_read (ops, &data);
+  char *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;
+  char *data;
+  int len = target_auxv_read (ops, &data);
+  char *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);
+	}
+
+      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 auxilary vector found, or failed reading it.");
+      else if (ents == 0)
+	error ("Auxilary 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.");
+}