[PATCH 1/6] Add constants for FreeBSD-specific auxiliary vector entry types.

[PATCH 1/6] Add constants for FreeBSD-specific auxiliary vector entry types.

[John Baldwin]

include/ChangeLog:

	* elf/common.h (AT_FREEBSD_EXECPATH, AT_FREEBSD_CANARY)
	(AT_FREEBSD_CANARYLEN, AT_FREEBSD_OSRELDATE, AT_FREEBSD_NCPUS)
	(AT_FREEBSD_PAGESIZES, AT_FREEBSD_PAGESIZESLEN)
	(AT_FREEBSD_TIMEKEEP, AT_FREEBSD_STACKPROT): Define.
---
 include/ChangeLog    |  7 +++++++
 include/elf/common.h | 10 ++++++++++
 2 files changed, 17 insertions(+)

diff --git a/include/ChangeLog b/include/ChangeLog
index 46a2f3a..248c1a6 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,10 @@
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
+	* elf/common.h (AT_FREEBSD_EXECPATH, AT_FREEBSD_CANARY)
+	(AT_FREEBSD_CANARYLEN, AT_FREEBSD_OSRELDATE, AT_FREEBSD_NCPUS)
+	(AT_FREEBSD_PAGESIZES, AT_FREEBSD_PAGESIZESLEN)
+	(AT_FREEBSD_TIMEKEEP, AT_FREEBSD_STACKPROT): Define.
+
 2016-06-14  John Baldwin  <jhb@FreeBSD.org>
 
 	* opcode/msp430-decode.h (MSP430_Size): Remove.
diff --git a/include/elf/common.h b/include/elf/common.h
index 087d876..d2da009d 100644
--- a/include/elf/common.h
+++ b/include/elf/common.h
@@ -1012,6 +1012,16 @@
 #define AT_L2_CACHESHAPE  36
 #define AT_L3_CACHESHAPE  37
 
+#define AT_FREEBSD_EXECPATH     15      /* Path to the executable. */
+#define AT_FREEBSD_CANARY       16      /* Canary for SSP. */
+#define AT_FREEBSD_CANARYLEN    17      /* Length of the canary. */
+#define AT_FREEBSD_OSRELDATE    18      /* OSRELDATE. */
+#define AT_FREEBSD_NCPUS        19      /* Number of CPUs. */
+#define AT_FREEBSD_PAGESIZES    20      /* Pagesizes. */
+#define AT_FREEBSD_PAGESIZESLEN 21      /* Number of pagesizes. */
+#define AT_FREEBSD_TIMEKEEP     22      /* Pointer to timehands. */
+#define AT_FREEBSD_STACKPROT    23      /* Initial stack protection. */
+
 #define AT_SUN_UID      2000    /* Effective user ID.  */
 #define AT_SUN_RUID     2001    /* Real user ID.  */
 #define AT_SUN_GID      2002    /* Effective group ID.  */
-- 
2.8.4

[PATCH 3/6] Fetch the ELF auxiliary vector from live processes on FreeBSD.

[John Baldwin]

Use the kern.proc.auxv.<pid> sysctl to fetch the ELF auxiliary vector for
a live process.

gdb/ChangeLog:

	* fbsd-nat.c [KERN_PROC_AUXV] New variable super_xfer_partial.
	(fbsd_xfer_partial): New function.
	(fbsd_nat_add_target) [KERN_PROC_AUXV] Set "to_xfer_partial" to
	"fbsd_xfer_partial".
---
 gdb/ChangeLog  |  7 ++++++
 gdb/fbsd-nat.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 81 insertions(+)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9e57431..b11174c 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
+	* fbsd-nat.c [KERN_PROC_AUXV] New variable super_xfer_partial.
+	(fbsd_xfer_partial): New function.
+	(fbsd_nat_add_target) [KERN_PROC_AUXV] Set "to_xfer_partial" to
+	"fbsd_xfer_partial".
+
 2016-06-14  John Baldwin  <jhb@FreeBSD.org>
 
 	* v850-tdep.c (v850_use_struct_convention): Trim type length checks.
diff --git a/gdb/fbsd-nat.c b/gdb/fbsd-nat.c
index b582abe..f9cfee6 100644
--- a/gdb/fbsd-nat.c
+++ b/gdb/fbsd-nat.c
@@ -206,6 +206,76 @@ fbsd_find_memory_regions (struct target_ops *self,
 }
 #endif
 
+#ifdef KERN_PROC_AUXV
+static enum target_xfer_status (*super_xfer_partial) (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);
+
+static enum target_xfer_status
+fbsd_xfer_partial (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)
+{
+  pid_t pid = ptid_get_pid (inferior_ptid);
+
+  switch (object)
+    {
+    case TARGET_OBJECT_AUXV:
+      {
+	struct cleanup *cleanup = make_cleanup (null_cleanup, NULL);
+	unsigned char *buf;
+	size_t buflen;
+	int mib[4];
+
+	if (writebuf)
+	  return TARGET_XFER_E_IO;
+	mib[0] = CTL_KERN;
+	mib[1] = KERN_PROC;
+	mib[2] = KERN_PROC_AUXV;
+	mib[3] = pid;
+	if (offset == 0)
+	  {
+	    buf = readbuf;
+	    buflen = len;
+	  }
+	else
+	  {
+	    buflen = offset + len;
+	    buf = XCNEWVEC (unsigned char, buflen);
+	    cleanup = make_cleanup (xfree, buf);
+	  }
+	if (sysctl (mib, 4, buf, &buflen, NULL, 0) == 0)
+	  {
+	    if (offset != 0)
+	      {
+		if (buflen > offset)
+		  {
+		    buflen -= offset;
+		    memcpy (readbuf, buf + offset, buflen);
+		  }
+		else
+		  buflen = 0;
+	      }
+	    do_cleanups (cleanup);
+	    *xfered_len = buflen;
+	    return (buflen == 0) ? TARGET_XFER_EOF : TARGET_XFER_OK;
+	  }
+	do_cleanups (cleanup);
+	return TARGET_XFER_E_IO;
+      }
+    default:
+      return super_xfer_partial (ops, object, annex, readbuf, writebuf, offset,
+				 len, xfered_len);
+    }
+}
+#endif
+
 #ifdef PT_LWPINFO
 static int debug_fbsd_lwp;
 
@@ -824,6 +894,10 @@ fbsd_nat_add_target (struct target_ops *t)
 {
   t->to_pid_to_exec_file = fbsd_pid_to_exec_file;
   t->to_find_memory_regions = fbsd_find_memory_regions;
+#ifdef KERN_PROC_AUXV
+  super_xfer_partial = t->to_xfer_partial;
+  t->to_xfer_partial = fbsd_xfer_partial;
+#endif
 #ifdef PT_LWPINFO
   t->to_thread_alive = fbsd_thread_alive;
   t->to_pid_to_str = fbsd_pid_to_str;
-- 
2.8.4

[PATCH 2/6] Add elfcore_grok_freebsd_note to parse FreeBSD ELF core notes.

[John Baldwin]

Move parsing of FreeBSD-specific ELF core notes out of elfcore_grok_note
into a new elfcore_grok_freebsd_note function.  Add core note grok routines
for FreeBSD's psinfo and prstatus notes while here rather than depending
on the native handling in elfcore_grok_note.

bfd/ChangeLog:

	* elf.c (elfcore_grok_note): Remove handling of NT_X86_XSTATE for
	FreeBSD.  Remove case for NT_FREEBSD_THRMISC.
	(elfcore_grok_freebsd_psinfo): New function.
	(elfcore_grok_freebsd_prstatus): New function.
	(elfcore_grok_freebsd_note): New function.
	(elf_parse_notes): Use "elfcore_grok_freebsd_note" for "FreeBSD"
	notes.
---
 bfd/ChangeLog |  10 +++++
 bfd/elf.c     | 138 ++++++++++++++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 139 insertions(+), 9 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 344e08b..881ce6d 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,13 @@
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
+	* elf.c (elfcore_grok_note): Remove handling of NT_X86_XSTATE for
+	FreeBSD.  Remove case for NT_FREEBSD_THRMISC.
+	(elfcore_grok_freebsd_psinfo): New function.
+	(elfcore_grok_freebsd_prstatus): New function.
+	(elfcore_grok_freebsd_note): New function.
+	(elf_parse_notes): Use "elfcore_grok_freebsd_note" for "FreeBSD"
+	notes.
+
 2016-06-15  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* elf32-i386.c (elf_i386_check_relocs): Check SEC_ALLOC before
diff --git a/bfd/elf.c b/bfd/elf.c
index aaf2b53..2d8f621 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -9327,9 +9327,6 @@ elfcore_grok_note (bfd *abfd, Elf_Internal_Note *note)
       if (note->namesz == 6
 	  && strcmp (note->namedata, "LINUX") == 0)
 	return elfcore_grok_xstatereg (abfd, note);
-      else if (note->namesz == 8
-	  && strcmp (note->namedata, "FreeBSD") == 0)
-	return elfcore_grok_xstatereg (abfd, note);
       else
 	return TRUE;
 
@@ -9485,12 +9482,6 @@ elfcore_grok_note (bfd *abfd, Elf_Internal_Note *note)
       return elfcore_make_note_pseudosection (abfd, ".note.linuxcore.siginfo",
 					      note);
 
-    case NT_FREEBSD_THRMISC:
-      if (note->namesz == 8
-	  && strcmp (note->namedata, "FreeBSD") == 0)
-	return elfcore_make_note_pseudosection (abfd, ".thrmisc", note);
-      else
-	return TRUE;
     }
 }
 
@@ -9556,6 +9547,134 @@ elfobj_grok_stapsdt_note (bfd *abfd, Elf_Internal_Note *note)
 }
 
 static bfd_boolean
+elfcore_grok_freebsd_psinfo (bfd *abfd, Elf_Internal_Note *note)
+{
+  size_t offset;
+
+  /* Check for version 1 in pr_version. */
+  if (bfd_h_get_32 (abfd, (bfd_byte *) note->descdata) != 1)
+    return FALSE;
+  offset = 4;
+
+  /* Skip over pr_psinfosz. */
+  switch (abfd->arch_info->bits_per_word)
+    {
+    case 32:
+      offset += 4;
+      break;
+
+    case 64:
+      offset += 4;	/* Padding before pr_psinfosz. */
+      offset += 8;
+      break;
+
+    default:
+      return FALSE;
+    }
+
+  /* pr_fname is PRFNAMESZ (16) + 1 bytes in size.  */
+  elf_tdata (abfd)->core->program
+    = _bfd_elfcore_strndup (abfd, note->descdata + offset, 17);
+  offset += 17;
+
+  /* pr_psargs is PRARGSZ (80) + 1 bytes in size.  */
+  elf_tdata (abfd)->core->command
+    = _bfd_elfcore_strndup (abfd, note->descdata + offset, 81);
+
+  return TRUE;
+}
+  
+static bfd_boolean
+elfcore_grok_freebsd_prstatus (bfd *abfd, Elf_Internal_Note *note)
+{
+  size_t offset;
+  size_t size;
+
+  /* Check for version 1 in pr_version. */
+  if (bfd_h_get_32 (abfd, (bfd_byte *) note->descdata) != 1)
+    return FALSE;
+  offset = 4;
+
+  /* Skip over pr_statussz.  */
+  switch (abfd->arch_info->bits_per_word)
+    {
+    case 32:
+      offset += 4;
+      break;
+
+    case 64:
+      offset += 4;	/* Padding before pr_statussz. */
+      offset += 8;
+      break;
+
+    default:
+      return FALSE;
+    }
+
+  /* Extract size of pr_reg from pr_gregsetsz.  */
+  if (abfd->arch_info->bits_per_word == 32)
+    size = bfd_h_get_32 (abfd, (bfd_byte *) note->descdata + offset);
+  else
+    size = bfd_h_get_64 (abfd, (bfd_byte *) note->descdata + offset);
+
+  /* Skip over pr_gregsetsz and pr_fpregsetsz. */
+  offset += (abfd->arch_info->bits_per_word / 8) * 2;
+
+  /* Skip over pr_osreldate. */
+  offset += 4;
+
+  /* Read signal from pr_cursig. */
+  if (elf_tdata (abfd)->core->signal == 0)
+    elf_tdata (abfd)->core->signal
+      = bfd_h_get_32 (abfd, (bfd_byte *) note->descdata + offset);
+  offset += 4;
+
+  /* Read TID from pr_pid. */
+  elf_tdata (abfd)->core->lwpid
+      = bfd_h_get_32 (abfd, (bfd_byte *) note->descdata + offset);
+  offset += 4;
+
+  /* Padding before pr_reg. */
+  if (abfd->arch_info->bits_per_word == 64)
+    offset += 4;
+
+  /* Make a ".reg/999" section and a ".reg" section.  */
+  return _bfd_elfcore_make_pseudosection (abfd, ".reg",
+					  size, note->descpos + offset);
+}
+
+static bfd_boolean
+elfcore_grok_freebsd_note (bfd *abfd, Elf_Internal_Note *note)
+{
+  switch (note->type)
+    {
+    case NT_PRSTATUS:
+      return elfcore_grok_freebsd_prstatus (abfd, note);
+
+    case NT_FPREGSET:
+      return elfcore_grok_prfpreg (abfd, note);
+
+    case NT_PRPSINFO:
+      return elfcore_grok_freebsd_psinfo (abfd, note);
+
+    case NT_FREEBSD_THRMISC:
+      if (note->namesz == 8)
+	return elfcore_make_note_pseudosection (abfd, ".thrmisc", note);
+      else
+	return TRUE;
+
+    case NT_X86_XSTATE:
+      if (note->namesz == 8)
+	return elfcore_grok_xstatereg (abfd, note);
+      else
+	return TRUE;
+
+    default:
+      return TRUE;
+    }
+}
+
+static bfd_boolean
 elfcore_netbsd_get_lwpid (Elf_Internal_Note *note, int *lwpidp)
 {
   char *cp;
@@ -10467,6 +10586,7 @@ elf_parse_notes (bfd *abfd, char *buf, size_t size, file_ptr offset)
 	    grokers[] =
 	    {
 	      GROKER_ELEMENT ("", elfcore_grok_note),
+	      GROKER_ELEMENT ("FreeBSD", elfcore_grok_freebsd_note),
 	      GROKER_ELEMENT ("NetBSD-CORE", elfcore_grok_netbsd_note),
 	      GROKER_ELEMENT ( "OpenBSD", elfcore_grok_openbsd_note),
 	      GROKER_ELEMENT ("QNX", elfcore_grok_nto_note),
-- 
2.8.4

[PATCH 0/6] Add ELF auxiliary vector handling for FreeBSD

[John Baldwin]

This patch series fixes 'info auxv' to work on live binaries and cores
for FreeBSD.  I believe most of these patches are straightforward.
I broke out parsing of FreeBSD-specific ELF core notes to avoid a
collision with duplicate NT_* values (NT_FREEBSD_PROCSTAT_AUXV conflicts
with NT_LWPSTATUS).  The biggest change is adding a new gdbarch method
to handle formatting individual auxv vectors.  FreeBSD uses AT_* constants
that overlap with existing AT_* constants but with different meanings.
One result of making the interpretation of AT_* constants a gdbarch
method is that 'info auxv' shows the correct output (Linux values)
when gdb inspects a Linux binary executing on FreeBSD via FreeBSD's
Linux ABI support.

John Baldwin (6):
  Add constants for FreeBSD-specific auxiliary vector entry types.
  Add elfcore_grok_freebsd_note to parse FreeBSD ELF core notes.
  Fetch the ELF auxiliary vector from live processes on FreeBSD.
  Create a psuedo section for the ELF AUXV core dump note on FreeBSD.
  Add a new gdbarch method to print a single AUXV entry.
  Add a gdbarch 'print_auxv' method for FreeBSD ABIs.

 bfd/ChangeLog        |  15 ++++
 bfd/elf.c            | 152 +++++++++++++++++++++++++++++++++++++---
 gdb/ChangeLog        |  23 +++++++
 gdb/auxv.c           | 191 ++++++++++++++++++++++++++++-----------------------
 gdb/auxv.h           |   8 +++
 gdb/fbsd-nat.c       |  74 ++++++++++++++++++++
 gdb/fbsd-tdep.c      |  33 +++++++++
 gdb/gdbarch.c        |  32 +++++++++
 gdb/gdbarch.h        |  11 +++
 gdb/gdbarch.sh       |   6 ++
 include/ChangeLog    |   7 ++
 include/elf/common.h |  10 +++
 12 files changed, 467 insertions(+), 95 deletions(-)

-- 
2.8.4

[PATCH 6/6] Add a gdbarch 'print_auxv' method for FreeBSD ABIs.

[John Baldwin]

Add a 'print_auxv' method for FreeBSD ABIs that parses FreeBSD-specific
auxiliary vector entries and outputs a suitable description using
fprint_single_auxv.

gdb/ChangeLog:

	* fbsd-tdep.c: Include "auxv.h".
	(fbsd_print_auxv): New function.
	(fbsd_init_abi): Install gdbarch "print_auxv" method.
---
 gdb/ChangeLog   |  6 ++++++
 gdb/fbsd-tdep.c | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2426a2f..27d4620 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,11 @@
 2016-06-15  John Baldwin  <jhb@FreeBSD.org>
 
+	* fbsd-tdep.c: Include "auxv.h".
+	(fbsd_print_auxv): New function.
+	(fbsd_init_abi): Install gdbarch "print_auxv" method.
+
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
 	* auxv.c (fprint_single_auxv): New function.
 	(default_print_auxv): New function.
 	(fprint_target_auxv): Use gdbarch_print_auxv and default_print_auxv.
diff --git a/gdb/fbsd-tdep.c b/gdb/fbsd-tdep.c
index 7310ea0..8aca570 100644
--- a/gdb/fbsd-tdep.c
+++ b/gdb/fbsd-tdep.c
@@ -18,6 +18,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "defs.h"
+#include "auxv.h"
 #include "gdbcore.h"
 #include "inferior.h"
 #include "regcache.h"
@@ -283,6 +284,37 @@ fbsd_make_corefile_notes (struct gdbarch *gdbarch, bfd *obfd, int *note_size)
   return note_data;
 }
 
+static int
+fbsd_print_auxv (struct gdbarch *gdbarch, struct ui_file *file, CORE_ADDR type,
+		 CORE_ADDR val)
+{
+  const char *name;
+  const char *description;
+  enum auxv_format flavor;
+
+  switch (type)
+    {
+#define _TAGNAME(tag) #tag
+#define TAGNAME(tag) _TAGNAME(AT_##tag)
+#define TAG(tag, text, kind) \
+      case AT_FREEBSD_##tag: name = TAGNAME(tag); description = text; flavor = kind; break
+      TAG (EXECPATH, _("Executable path"), str);
+      TAG (CANARY, _("Canary for SSP"), hex);
+      TAG (CANARYLEN, ("Length of the SSP canary"), dec);
+      TAG (OSRELDATE, _("OSRELDATE"), dec);
+      TAG (NCPUS, _("Number of CPUs"), dec);
+      TAG (PAGESIZES, _("Pagesizes"), hex);
+      TAG (PAGESIZESLEN, _("Number of pagesizes"), dec);
+      TAG (TIMEKEEP, _("Pointer to timehands"), hex);
+      TAG (STACKPROT, _("Initial stack protection"), hex);
+    default:
+      return (0);
+    }
+
+  fprint_single_auxv (file, name, description, flavor, type, val);
+  return (1);
+}
+
 /* To be called from GDB_OSABI_FREEBSD_ELF handlers. */
 
 void
@@ -291,4 +323,5 @@ fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   set_gdbarch_core_pid_to_str (gdbarch, fbsd_core_pid_to_str);
   set_gdbarch_core_thread_name (gdbarch, fbsd_core_thread_name);
   set_gdbarch_make_corefile_notes (gdbarch, fbsd_make_corefile_notes);
+  set_gdbarch_print_auxv (gdbarch, fbsd_print_auxv);
 }
-- 
2.8.4

[PATCH 4/6] Create a psuedo section for the ELF AUXV core dump note on FreeBSD.

[John Baldwin]

The procstat AUXV core dump note in FreeBSD consists of 32-bit integer
followed by an array of auxiliary vector entries.

bfd/ChangeLog:

	* elf.c (elfcore_grok_freebsd_note): Handle NT_FREEBSD_PROCSTAT_AUXV
	notes.
---
 bfd/ChangeLog |  5 +++++
 bfd/elf.c     | 14 ++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 881ce6d..7afc44e 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,10 @@
 2016-06-15  John Baldwin  <jhb@FreeBSD.org>
 
+	* elf.c (elfcore_grok_freebsd_note): Handle NT_FREEBSD_PROCSTAT_AUXV
+	notes.
+
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
 	* elf.c (elfcore_grok_note): Remove handling of NT_X86_XSTATE for
 	FreeBSD.  Remove case for NT_FREEBSD_THRMISC.
 	(elfcore_grok_freebsd_psinfo): New function.
diff --git a/bfd/elf.c b/bfd/elf.c
index 2d8f621..d947cf3 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -9663,6 +9663,20 @@ elfcore_grok_freebsd_note (bfd *abfd, Elf_Internal_Note *note)
       else
 	return TRUE;
 
+    case NT_FREEBSD_PROCSTAT_AUXV:
+      {
+	asection *sect = bfd_make_section_anyway_with_flags (abfd, ".auxv",
+							     SEC_HAS_CONTENTS);
+
+	if (sect == NULL)
+	  return FALSE;
+	sect->size = note->descsz - 4;
+	sect->filepos = note->descpos + 4;
+	sect->alignment_power = 1 + bfd_get_arch_size (abfd) / 32;
+
+	return TRUE;
+      }
+      
     case NT_X86_XSTATE:
       if (note->namesz == 8)
 	return elfcore_grok_xstatereg (abfd, note);
-- 
2.8.4

[PATCH 5/6] Add a new gdbarch method to print a single AUXV entry.

[John Baldwin]

Different platforms have different meanings for auxiliary vector
entries.  The 'print_auxv' gdbarch method allows an architecture
to output a suitable description for platform-specific entries.

A fprint_single_auxv function is split out of fprint_target_auxv.
This function outputs the description of a single auxiliary vector
entry to the specified file using caller-supplied formatting and
strings to describe the vector type.

The existing switch on auxiliary vector types is moved out of
fprint_target_auxv into a new default_print_auxv function.
default_print_auxv chooses an appropriate format and description
and calls fprint_single_auxv to describe a single vector entry.

fprint_target_auxv now invokes the gdbarch 'print_auxv' function
on each vector entry.  If the function is not present or returns
zero, default_printf_auxv is called to output a description for
the vector.

gdb/ChangeLog:

	* auxv.c (fprint_single_auxv): New function.
	(default_print_auxv): New function.
	(fprint_target_auxv): Use gdbarch_print_auxv and default_print_auxv.
	* auxv.h (enum auxv_format): New enum.
	(fprint_single_auxv): Declare.
	* gdbarch.sh (print_auxv): New.
	* gdbarch.c, gdbarch.h: Re-generated.
---
 gdb/ChangeLog  |  10 +++
 gdb/auxv.c     | 191 +++++++++++++++++++++++++++++++--------------------------
 gdb/auxv.h     |   8 +++
 gdb/gdbarch.c  |  32 ++++++++++
 gdb/gdbarch.h  |  11 ++++
 gdb/gdbarch.sh |   6 ++
 6 files changed, 172 insertions(+), 86 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index b11174c..2426a2f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,15 @@
 2016-06-15  John Baldwin  <jhb@FreeBSD.org>
 
+	* auxv.c (fprint_single_auxv): New function.
+	(default_print_auxv): New function.
+	(fprint_target_auxv): Use gdbarch_print_auxv and default_print_auxv.
+	* auxv.h (enum auxv_format): New enum.
+	(fprint_single_auxv): Declare.
+	* gdbarch.sh (print_auxv): New.
+	* gdbarch.c, gdbarch.h: Re-generated.
+
+2016-06-15  John Baldwin  <jhb@FreeBSD.org>
+
 	* fbsd-nat.c [KERN_PROC_AUXV] New variable super_xfer_partial.
 	(fbsd_xfer_partial): New function.
 	(fbsd_nat_add_target) [KERN_PROC_AUXV] Set "to_xfer_partial" to
diff --git a/gdb/auxv.c b/gdb/auxv.c
index 396862e..275c23e 100644
--- a/gdb/auxv.c
+++ b/gdb/auxv.c
@@ -407,10 +407,112 @@ target_auxv_search (struct target_ops *ops, CORE_ADDR match, CORE_ADDR *valp)
 }
 
 
+/* Print a description of a single AUXV entry on the specified file.  */
+void
+fprint_single_auxv (struct ui_file *file, const char *name,
+		    const char *description, enum auxv_format flavor,
+		    CORE_ADDR type, CORE_ADDR val)
+{
+  fprintf_filtered (file, "%-4s %-20s %-30s ",
+		    plongest (type), name, description);
+  switch (flavor)
+    {
+    case dec:
+      fprintf_filtered (file, "%s\n", plongest (val));
+      break;
+    case hex:
+      fprintf_filtered (file, "%s\n", paddress (target_gdbarch (), val));
+      break;
+    case str:
+      {
+	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;
+    }
+}
+
+static void
+default_print_auxv (struct ui_file *file, CORE_ADDR type, CORE_ADDR val)
+{
+  const char *name = "???";
+  const char *description = "";
+  enum auxv_format 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_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_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);
+      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);
+    }
+
+  fprint_single_auxv (file, name, description, flavor, type, val);
+}
+		    
 /* Print the contents of the target's AUXV on the specified file.  */
 int
 fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 {
+  struct gdbarch *gdbarch = target_gdbarch();
   CORE_ADDR type, val;
   gdb_byte *data;
   gdb_byte *ptr;
@@ -426,93 +528,10 @@ fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
 
   while (target_auxv_parse (ops, &ptr, data + info->length, &type, &val) > 0)
     {
-      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_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_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);
-	  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);
-	}
+      if (!gdbarch_print_auxv_p (gdbarch)
+	  || gdbarch_print_auxv (gdbarch, file, type, val) == 0)
+	default_print_auxv (file, type, val);
 
-      fprintf_filtered (file, "%-4s %-20s %-30s ",
-			plongest (type), name, description);
-      switch (flavor)
-	{
-	case dec:
-	  fprintf_filtered (file, "%s\n", plongest (val));
-	  break;
-	case hex:
-	  fprintf_filtered (file, "%s\n", paddress (target_gdbarch (), val));
-	  break;
-	case str:
-	  {
-	    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;
       if (type == AT_NULL)
 	break;
diff --git a/gdb/auxv.h b/gdb/auxv.h
index 9efe604..91d94f9 100644
--- a/gdb/auxv.h
+++ b/gdb/auxv.h
@@ -46,6 +46,14 @@ extern int target_auxv_parse (struct target_ops *ops,
 extern int target_auxv_search (struct target_ops *ops,
 			       CORE_ADDR match, CORE_ADDR *valp);
 
+/* Print a description of a single AUXV entry on the specified file.  */
+enum auxv_format { dec, hex, str };
+
+extern void fprint_single_auxv (struct ui_file *file, const char *name,
+				const char *description,
+				enum auxv_format flavor, CORE_ADDR type,
+				CORE_ADDR val);
+
 /* Print the contents of the target's AUXV on the specified file.  */
 extern int fprint_target_auxv (struct ui_file *file, struct target_ops *ops);
 
diff --git a/gdb/gdbarch.c b/gdb/gdbarch.c
index 313502b..15a4a98 100644
--- a/gdb/gdbarch.c
+++ b/gdb/gdbarch.c
@@ -328,6 +328,7 @@ struct gdbarch
   gdbarch_insn_is_ret_ftype *insn_is_ret;
   gdbarch_insn_is_jump_ftype *insn_is_jump;
   gdbarch_auxv_parse_ftype *auxv_parse;
+  gdbarch_print_auxv_ftype *print_auxv;
   gdbarch_vsyscall_range_ftype *vsyscall_range;
   gdbarch_infcall_mmap_ftype *infcall_mmap;
   gdbarch_infcall_munmap_ftype *infcall_munmap;
@@ -678,6 +679,7 @@ verify_gdbarch (struct gdbarch *gdbarch)
   /* Skip verify of insn_is_ret, invalid_p == 0 */
   /* Skip verify of insn_is_jump, invalid_p == 0 */
   /* Skip verify of auxv_parse, has predicate.  */
+  /* Skip verify of print_auxv, has predicate.  */
   /* Skip verify of vsyscall_range, invalid_p == 0 */
   /* Skip verify of infcall_mmap, invalid_p == 0 */
   /* Skip verify of infcall_munmap, invalid_p == 0 */
@@ -1167,6 +1169,12 @@ gdbarch_dump (struct gdbarch *gdbarch, struct ui_file *file)
                       "gdbarch_dump: pointer_to_address = <%s>\n",
                       host_address_to_string (gdbarch->pointer_to_address));
   fprintf_unfiltered (file,
+                      "gdbarch_dump: gdbarch_print_auxv_p() = %d\n",
+                      gdbarch_print_auxv_p (gdbarch));
+  fprintf_unfiltered (file,
+                      "gdbarch_dump: print_auxv = <%s>\n",
+                      host_address_to_string (gdbarch->print_auxv));
+  fprintf_unfiltered (file,
                       "gdbarch_dump: print_float_info = <%s>\n",
                       host_address_to_string (gdbarch->print_float_info));
   fprintf_unfiltered (file,
@@ -4770,6 +4778,30 @@ set_gdbarch_auxv_parse (struct gdbarch *gdbarch,
 }
 
 int
+gdbarch_print_auxv_p (struct gdbarch *gdbarch)
+{
+  gdb_assert (gdbarch != NULL);
+  return gdbarch->print_auxv != NULL;
+}
+
+int
+gdbarch_print_auxv (struct gdbarch *gdbarch, struct ui_file *file, CORE_ADDR type, CORE_ADDR val)
+{
+  gdb_assert (gdbarch != NULL);
+  gdb_assert (gdbarch->print_auxv != NULL);
+  if (gdbarch_debug >= 2)
+    fprintf_unfiltered (gdb_stdlog, "gdbarch_print_auxv called\n");
+  return gdbarch->print_auxv (gdbarch, file, type, val);
+}
+
+void
+set_gdbarch_print_auxv (struct gdbarch *gdbarch,
+                        gdbarch_print_auxv_ftype print_auxv)
+{
+  gdbarch->print_auxv = print_auxv;
+}
+
+int
 gdbarch_vsyscall_range (struct gdbarch *gdbarch, struct mem_range *range)
 {
   gdb_assert (gdbarch != NULL);
diff --git a/gdb/gdbarch.h b/gdb/gdbarch.h
index a6366fc..9cd1175 100644
--- a/gdb/gdbarch.h
+++ b/gdb/gdbarch.h
@@ -1464,6 +1464,17 @@ typedef int (gdbarch_auxv_parse_ftype) (struct gdbarch *gdbarch, gdb_byte **read
 extern int gdbarch_auxv_parse (struct gdbarch *gdbarch, gdb_byte **readptr, gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp);
 extern void set_gdbarch_auxv_parse (struct gdbarch *gdbarch, gdbarch_auxv_parse_ftype *auxv_parse);
 
+/* Print the description of a single auxv entry described by TYPE and VAL
+   to FILE.  Return 0 and output no description if the TYPE is unknown.
+   Return 0 if the TYPE of the auxv entry is unknown.
+   Return 1 if a description was output. */
+
+extern int gdbarch_print_auxv_p (struct gdbarch *gdbarch);
+
+typedef int (gdbarch_print_auxv_ftype) (struct gdbarch *gdbarch, struct ui_file *file, CORE_ADDR type, CORE_ADDR val);
+extern int gdbarch_print_auxv (struct gdbarch *gdbarch, struct ui_file *file, CORE_ADDR type, CORE_ADDR val);
+extern void set_gdbarch_print_auxv (struct gdbarch *gdbarch, gdbarch_print_auxv_ftype *print_auxv);
+
 /* Find the address range of the current inferior's vsyscall/vDSO, and
    write it to *RANGE.  If the vsyscall's length can't be determined, a
    range with zero length is returned.  Returns true if the vsyscall is
diff --git a/gdb/gdbarch.sh b/gdb/gdbarch.sh
index f170c10..1b4342f 100755
--- a/gdb/gdbarch.sh
+++ b/gdb/gdbarch.sh
@@ -1110,6 +1110,12 @@ m:int:insn_is_jump:CORE_ADDR addr:addr::default_insn_is_jump::0
 # Return 1 if an entry was read into *TYPEP and *VALP.
 M:int:auxv_parse:gdb_byte **readptr, gdb_byte *endptr, CORE_ADDR *typep, CORE_ADDR *valp:readptr, endptr, typep, valp
 
+# Print the description of a single auxv entry described by TYPE and VAL
+# to FILE.  Return 0 and output no description if the TYPE is unknown.
+# Return 0 if the TYPE of the auxv entry is unknown.
+# Return 1 if a description was output.
+M:int:print_auxv:struct ui_file *file, CORE_ADDR type, CORE_ADDR val:file, type, val
+
 # Find the address range of the current inferior's vsyscall/vDSO, and
 # write it to *RANGE.  If the vsyscall's length can't be determined, a
 # range with zero length is returned.  Returns true if the vsyscall is
-- 
2.8.4

Re: [PATCH 1/6] Add constants for FreeBSD-specific auxiliary vector entry types.

[Nick Clifton]

Hi John,

> include/ChangeLog:
> 
> 	* elf/common.h (AT_FREEBSD_EXECPATH, AT_FREEBSD_CANARY)
> 	(AT_FREEBSD_CANARYLEN, AT_FREEBSD_OSRELDATE, AT_FREEBSD_NCPUS)
> 	(AT_FREEBSD_PAGESIZES, AT_FREEBSD_PAGESIZESLEN)
> 	(AT_FREEBSD_TIMEKEEP, AT_FREEBSD_STACKPROT): Define.

Approved - please apply.

Cheers
  Nick

Re: [PATCH 4/6] Create a psuedo section for the ELF AUXV core dump note on FreeBSD.

[Nick Clifton]

Hi John,

> bfd/ChangeLog:
> 
> 	* elf.c (elfcore_grok_freebsd_note): Handle NT_FREEBSD_PROCSTAT_AUXV
> 	notes.
 
Approved - please apply.

Cheers
  Nick

Re: [PATCH 2/6] Add elfcore_grok_freebsd_note to parse FreeBSD ELF core notes.

[Nick Clifton]

Hi John,

> bfd/ChangeLog:
> 
> 	* elf.c (elfcore_grok_note): Remove handling of NT_X86_XSTATE for
> 	FreeBSD.  Remove case for NT_FREEBSD_THRMISC.
> 	(elfcore_grok_freebsd_psinfo): New function.
> 	(elfcore_grok_freebsd_prstatus): New function.
> 	(elfcore_grok_freebsd_note): New function.
> 	(elf_parse_notes): Use "elfcore_grok_freebsd_note" for "FreeBSD"
> 	notes.
 
Approved - please apply.

Cheers
  Nick

Re: [PATCH 0/6] Add ELF auxiliary vector handling for FreeBSD

[John Baldwin]

On Wednesday, June 15, 2016 11:01:56 PM John Baldwin wrote:
> This patch series fixes 'info auxv' to work on live binaries and cores
> for FreeBSD.  I believe most of these patches are straightforward.
> I broke out parsing of FreeBSD-specific ELF core notes to avoid a
> collision with duplicate NT_* values (NT_FREEBSD_PROCSTAT_AUXV conflicts
> with NT_LWPSTATUS).  The biggest change is adding a new gdbarch method
> to handle formatting individual auxv vectors.  FreeBSD uses AT_* constants
> that overlap with existing AT_* constants but with different meanings.
> One result of making the interpretation of AT_* constants a gdbarch
> method is that 'info auxv' shows the correct output (Linux values)
> when gdb inspects a Linux binary executing on FreeBSD via FreeBSD's
> Linux ABI support.

Ping?

The binutils patches have been ok'd, but the gdb patches haven't been
reviewed yet.

-- 
John Baldwin

Re: [PATCH 3/6] Fetch the ELF auxiliary vector from live processes on FreeBSD.

[Pedro Alves]

On 06/16/2016 07:01 AM, John Baldwin wrote:

> +static enum target_xfer_status
> +fbsd_xfer_partial (struct target_ops *ops, enum target_object object,

"Implement foo"-style intro comment missing.

> +  switch (object)
> +    {
> +    case TARGET_OBJECT_AUXV:
> +      {
> +	struct cleanup *cleanup = make_cleanup (null_cleanup, NULL);
> +	unsigned char *buf;
> +	size_t buflen;
> +	int mib[4];
> +
> +	if (writebuf)

writebuf != NULL.

Otherwise LGTM.

Thanks,
Pedro Alves

Re: [PATCH 5/6] Add a new gdbarch method to print a single AUXV entry.

[Pedro Alves]

On 06/16/2016 07:02 AM, John Baldwin wrote:
> Different platforms have different meanings for auxiliary vector
> entries.  The 'print_auxv' gdbarch method allows an architecture
> to output a suitable description for platform-specific entries.
> 
> A fprint_single_auxv function is split out of fprint_target_auxv.
> This function outputs the description of a single auxiliary vector
> entry to the specified file using caller-supplied formatting and
> strings to describe the vector type.
> 
> The existing switch on auxiliary vector types is moved out of
> fprint_target_auxv into a new default_print_auxv function.
> default_print_auxv chooses an appropriate format and description
> and calls fprint_single_auxv to describe a single vector entry.
> 
> fprint_target_auxv now invokes the gdbarch 'print_auxv' function
> on each vector entry.  If the function is not present or returns
> zero, default_printf_auxv is called to output a description for
> the vector.

I like the idea.  Though, I think we can simplify this.  How about:

- make default_print_auxv be the default gdbarch_print_auxv
  implementation, in gdbarch.sh.   

- make fprint_target_auxv calls gdbarch_print_auxv unconditionally.

- remove the support for gdbarch_print_auxv returning 0.  Instead,
  implementations that want to defer to default_print_auxv simply
  call it directly.


Also, I think it'd be a bit less confusing to rename things like this:

  gdbarch_print_auxv -> gdbarch_print_auxv_entry
  default_print_auxv -> default_print_auxv_entry
  fprint_single_auxv -> fprint_auxv_entry

This way methods that print a single entry are consistently named,
and not so easily confused with methods that print the whole table,
like fprint_target_auxv.

>  
>  
> +/* Print a description of a single AUXV entry on the specified file.  */
> +void

Empty line between comment and function.

> +fprint_single_auxv (struct ui_file *file, const char *name,
> +		    const char *description, enum auxv_format flavor,
> +		    CORE_ADDR type, CORE_ADDR val)
> +{
> +  fprintf_filtered (file, "%-4s %-20s %-30s ",
> +		    plongest (type), name, description);

If not translatable, wrap string in () [not _()], in order to
avoid ARI complaints.

> +  switch (flavor)
> +    {
> +    case dec:
> +      fprintf_filtered (file, "%s\n", plongest (val));
> +      break;
> +    case hex:
> +      fprintf_filtered (file, "%s\n", paddress (target_gdbarch (), val));
> +      break;
> +    case str:
> +      {
> +	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");
> +      }

Likewise the other format strings.


> +
> +static void
> +default_print_auxv (struct ui_file *file, CORE_ADDR type, CORE_ADDR val)
> +{

Intro comment.   Something like "default implementation of ...".


> +		    
>  /* Print the contents of the target's AUXV on the specified file.  */
>  int
>  fprint_target_auxv (struct ui_file *file, struct target_ops *ops)
>  {
> +  struct gdbarch *gdbarch = target_gdbarch();

Space before open parenthesis.

> diff --git a/gdb/auxv.h b/gdb/auxv.h
> index 9efe604..91d94f9 100644
> --- a/gdb/auxv.h
> +++ b/gdb/auxv.h
> @@ -46,6 +46,14 @@ extern int target_auxv_parse (struct target_ops *ops,
>  extern int target_auxv_search (struct target_ops *ops,
>  			       CORE_ADDR match, CORE_ADDR *valp);
>  
> +/* Print a description of a single AUXV entry on the specified file.  */
> +enum auxv_format { dec, hex, str };

These very generic names used to be OK, because they were
defined inside the function.  But now that this is in a header,
the potential for conflict is much higher.  hex could conflict
with std::hex, for instance.  Please rename the values to
for example: AUXV_FORMAT_DEC / AUXV_FORMAT_HEX / AUXV_FORMAT_STR.
We should add a comment for what each value means, too, since
we lost the pass of obvious-because-of-locality.

> +
> +extern void fprint_single_auxv (struct ui_file *file, const char *name,
> +				const char *description,
> +				enum auxv_format flavor, CORE_ADDR type,

I'd find it more consistent to call parameter "format" instead of "flavor",
which then avoids people looking for enum auxv_flavor.

> +# Print the description of a single auxv entry described by TYPE and VAL
> +# to FILE.  Return 0 and output no description if the TYPE is unknown.
> +# Return 0 if the TYPE of the auxv entry is unknown.
> +# Return 1 if a description was output.
> +M:int:print_auxv:struct ui_file *file, CORE_ADDR type, CORE_ADDR val:file, type, val

Thanks,
Pedro Alves

Re: [PATCH 6/6] Add a gdbarch 'print_auxv' method for FreeBSD ABIs.

[Pedro Alves]

On 06/16/2016 07:02 AM, John Baldwin wrote:

>  
> +static int
> +fbsd_print_auxv (struct gdbarch *gdbarch, struct ui_file *file, CORE_ADDR type,
> +		 CORE_ADDR val)

Missing intro comment.

> +{
> +  const char *name;
> +  const char *description;
> +  enum auxv_format flavor;
> +
> +  switch (type)
> +    {
> +#define _TAGNAME(tag) #tag
> +#define TAGNAME(tag) _TAGNAME(AT_##tag)
> +#define TAG(tag, text, kind) \
> +      case AT_FREEBSD_##tag: name = TAGNAME(tag); description = text; flavor = kind; break
> +      TAG (EXECPATH, _("Executable path"), str);
> +      TAG (CANARY, _("Canary for SSP"), hex);
> +      TAG (CANARYLEN, ("Length of the SSP canary"), dec);
> +      TAG (OSRELDATE, _("OSRELDATE"), dec);
> +      TAG (NCPUS, _("Number of CPUs"), dec);
> +      TAG (PAGESIZES, _("Pagesizes"), hex);
> +      TAG (PAGESIZESLEN, _("Number of pagesizes"), dec);
> +      TAG (TIMEKEEP, _("Pointer to timehands"), hex);
> +      TAG (STACKPROT, _("Initial stack protection"), hex);
> +    default:
> +      return (0);

Write:

      return 0;

However, with the suggestion in the previous patch, this would
be a direct call to default_print_auxv_entry.

> +    }
> +
> +  fprint_single_auxv (file, name, description, flavor, type, val);
> +  return (1);

  return 1;

Thanks,
Pedro Alves

Re: [PATCH 4/6] Create a psuedo section for the ELF AUXV core dump note on FreeBSD.

[Pedro Alves]

"pseudo" :-)

Thanks,
Pedro Alves

Re: [PATCH 5/6] Add a new gdbarch method to print a single AUXV entry.

[John Baldwin]

On Tuesday, June 21, 2016 12:40:16 AM Pedro Alves wrote:
> On 06/16/2016 07:02 AM, John Baldwin wrote:
> > Different platforms have different meanings for auxiliary vector
> > entries.  The 'print_auxv' gdbarch method allows an architecture
> > to output a suitable description for platform-specific entries.
> > 
> > A fprint_single_auxv function is split out of fprint_target_auxv.
> > This function outputs the description of a single auxiliary vector
> > entry to the specified file using caller-supplied formatting and
> > strings to describe the vector type.
> > 
> > The existing switch on auxiliary vector types is moved out of
> > fprint_target_auxv into a new default_print_auxv function.
> > default_print_auxv chooses an appropriate format and description
> > and calls fprint_single_auxv to describe a single vector entry.
> > 
> > fprint_target_auxv now invokes the gdbarch 'print_auxv' function
> > on each vector entry.  If the function is not present or returns
> > zero, default_printf_auxv is called to output a description for
> > the vector.
> 
> I like the idea.  Though, I think we can simplify this.  How about:
> 
> - make default_print_auxv be the default gdbarch_print_auxv
>   implementation, in gdbarch.sh.   
> 
> - make fprint_target_auxv calls gdbarch_print_auxv unconditionally.
> 
> - remove the support for gdbarch_print_auxv returning 0.  Instead,
>   implementations that want to defer to default_print_auxv simply
>   call it directly.
> 
> 
> Also, I think it'd be a bit less confusing to rename things like this:
> 
>   gdbarch_print_auxv -> gdbarch_print_auxv_entry
>   default_print_auxv -> default_print_auxv_entry
>   fprint_single_auxv -> fprint_auxv_entry
> 
> This way methods that print a single entry are consistently named,
> and not so easily confused with methods that print the whole table,
> like fprint_target_auxv.

Agreed, thanks.  I've made these changes along with the auxv_format
enum rename and the other issues you've pointed out.  Will be posting
a v2 series with those fixes in a bit.

-- 
John Baldwin