[patch] core: use core_pid

[patch] core: use core_pid

[Aleksandar Ristovski]

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Hello,

This patch fixes minor issue: in corelow.c (add_to_thread_list) we use thread_id 
as pid and we ignore core_pid which is available. This gives confusing output 
from "info threads" since threads appear to belong to different processes.

The patch rectifies this situation.



Thanks,

Aleksandar Ristovski
QNX Software Systems



2008-02-26  Aleksandar Ristovski  <aristovski@qnx.com>

	* Makefile.in (corelow.o): Add elf_bfd_h.
	* corelow.c (elf-bfd.h): Add include.
	(add_to_thread_list): Use core_pid instead of using tid as pid.
	(get_core_register_section): Use tid from inferior_ptid instead of pid.
	

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Index: gdb/Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.984
diff -u -p -r1.984 Makefile.in
--- gdb/Makefile.in	20 Feb 2008 15:45:20 -0000	1.984
+++ gdb/Makefile.in	26 Feb 2008 19:20:38 -0000
@@ -1996,7 +1996,7 @@ corelow.o: corelow.c $(defs_h) $(arch_ut
 	$(inferior_h) $(symtab_h) $(command_h) $(bfd_h) $(target_h) \
 	$(gdbcore_h) $(gdbthread_h) $(regcache_h) $(regset_h) $(symfile_h) \
 	$(exec_h) $(readline_h) $(gdb_assert_h) \
-	$(exceptions_h) $(solib_h) $(filenames_h)
+	$(exceptions_h) $(solib_h) $(filenames_h) $(elf_bfd_h)
 core-regset.o: core-regset.c $(defs_h) $(command_h) $(gdbcore_h) \
 	$(inferior_h) $(target_h) $(regcache_h) $(gdb_string_h) $(gregset_h)
 cp-abi.o: cp-abi.c $(defs_h) $(value_h) $(cp_abi_h) $(command_h) $(gdbcmd_h) \
Index: gdb/corelow.c
===================================================================
RCS file: /cvs/src/src/gdb/corelow.c,v
retrieving revision 1.73
diff -u -p -r1.73 corelow.c
--- gdb/corelow.c	9 Feb 2008 13:45:33 -0000	1.73
+++ gdb/corelow.c	26 Feb 2008 19:20:43 -0000
@@ -45,6 +45,7 @@
 #include "exceptions.h"
 #include "solib.h"
 #include "filenames.h"
+#include "elf-bfd.h"
 
 
 #ifndef O_LARGEFILE
@@ -232,20 +233,22 @@ static void
 add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
 {
   int thread_id;
+  ptid_t ptid;
   asection *reg_sect = (asection *) reg_sect_arg;
 
   if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
     return;
 
   thread_id = atoi (bfd_section_name (abfd, asect) + 5);
-
-  add_thread (pid_to_ptid (thread_id));
+  gdb_assert (abfd != NULL && elf_tdata (abfd) != NULL);
+  ptid = ptid_build (elf_tdata (abfd)->core_pid, 0, thread_id);
+  add_thread (ptid);
 
 /* Warning, Will Robinson, looking at BFD private data! */
 
   if (reg_sect != NULL
       && asect->filepos == reg_sect->filepos)	/* Did we find .reg? */
-    inferior_ptid = pid_to_ptid (thread_id);	/* Yes, make it current */
+    inferior_ptid = ptid;	/* Yes, make it current */
 }
 
 /* This routine opens and sets up the core file bfd.  */
@@ -424,8 +427,8 @@ get_core_register_section (struct regcac
   char *contents;
 
   xfree (section_name);
-  if (PIDGET (inferior_ptid))
-    section_name = xstrprintf ("%s/%d", name, PIDGET (inferior_ptid));
+  if (ptid_get_tid (inferior_ptid))
+    section_name = xstrprintf ("%s/%ld", name, ptid_get_tid (inferior_ptid));
   else
     section_name = xstrdup (name);
 

Re: [patch] core: use core_pid

[Daniel Jacobowitz]

On Tue, Feb 26, 2008 at 02:37:58PM -0500, Aleksandar Ristovski wrote:
> +  gdb_assert (abfd != NULL && elf_tdata (abfd) != NULL);

What if it's not an ELF core file?

-- 
Daniel Jacobowitz
CodeSourcery

Re: [patch] core: use core_pid

[Aleksandar Ristovski]

Daniel Jacobowitz wrote:
> On Tue, Feb 26, 2008 at 02:37:58PM -0500, Aleksandar Ristovski wrote:
>> +  gdb_assert (abfd != NULL && elf_tdata (abfd) != NULL);
> 
> What if it's not an ELF core file?
> 
Didn't think about that (our core can only be ELF).

In that case, do you think something like this would work?

@@ -232,20 +233,24 @@ static void
  add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
  {
    int thread_id;
+  ptid_t ptid;
    asection *reg_sect = (asection *) reg_sect_arg;

    if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
      return;

    thread_id = atoi (bfd_section_name (abfd, asect) + 5);
-
-  add_thread (pid_to_ptid (thread_id));
+  if (abfd != NULL && elf_tdata (abfd) != NULL)
+    ptid = ptid_build (elf_tdata (abfd)->core_pid, 0, thread_id);
+  else
+    ptid = ptid_build (42, 0, thread_id);
+  add_thread (ptid);

  /* Warning, Will Robinson, looking at BFD private data! */

    if (reg_sect != NULL
        && asect->filepos == reg_sect->filepos)  /* Did we find .reg? */
-    inferior_ptid = pid_to_ptid (thread_id);   /* Yes, make it current */
+    inferior_ptid = ptid;      /* Yes, make it current */
  }

  /* This routine opens and sets up the core file bfd.  */

Re: [patch] core: use core_pid

[Daniel Jacobowitz]

On Tue, Feb 26, 2008 at 02:52:47PM -0500, Aleksandar Ristovski wrote:
> Daniel Jacobowitz wrote:
>> On Tue, Feb 26, 2008 at 02:37:58PM -0500, Aleksandar Ristovski wrote:
>>> +  gdb_assert (abfd != NULL && elf_tdata (abfd) != NULL);
>>
>> What if it's not an ELF core file?
>>
> Didn't think about that (our core can only be ELF).
>
> In that case, do you think something like this would work?

Not quite.  I recommend you take a look at bfd/elf.c and
bfd/elf64-x86-64.c to see some different ways ".reg/XXXX" sections are
created.  For QNX, you get .reg/TID.  But for other targets you get
(LWPID << 16) + PID and core_pid is updated as we go along.

It looks like the information GDB needs doesn't make it out of BFD.

-- 
Daniel Jacobowitz
CodeSourcery