gdbserver: turn target op 'pid_to_exec_file' into a method

gdbserver/ChangeLog:
2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>

	Turn process_stratum_target's pid_to_exec_file op into a method
	of process_target.

	* target.h (struct process_stratum_target): Remove the target op.
	(class process_target): Add the target op.  Also add
	'supports_pid_to_exec_file'.
	* target.cc (process_target::pid_to_exec_file): Define.
	(process_target::supports_pid_to_exec_file): Define.

	Update the derived classes and callers below.

	* server.cc (handle_qxfer_exec_file): Update.
	(handle_query): Update.
	* linux-low.cc (linux_target_ops): Update.
	(linux_process_target::supports_pid_to_exec_file): Define.
	(linux_process_target::pid_to_exec_file): Define.
	* linux-low.h (class linux_process_target): Update.
	* lynx-low.cc (lynx_target_ops): Update.
	* nto-low.cc (nto_target_ops): Update.
	* win32-low.cc (win32_target_ops): Update.

9 files changed, 65 insertions, 15 deletions

diff --git a/gdbserver/ChangeLog b/gdbserver/ChangeLog
index cd5ef1d..fcf4871 100644
--- a/gdbserver/ChangeLog
+++ b/gdbserver/ChangeLog
@@ -1,5 +1,28 @@
 2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>
 
+	Turn process_stratum_target's pid_to_exec_file op into a method
+	of process_target.
+
+	* target.h (struct process_stratum_target): Remove the target op.
+	(class process_target): Add the target op.  Also add
+	'supports_pid_to_exec_file'.
+	* target.cc (process_target::pid_to_exec_file): Define.
+	(process_target::supports_pid_to_exec_file): Define.
+
+	Update the derived classes and callers below.
+
+	* server.cc (handle_qxfer_exec_file): Update.
+	(handle_query): Update.
+	* linux-low.cc (linux_target_ops): Update.
+	(linux_process_target::supports_pid_to_exec_file): Define.
+	(linux_process_target::pid_to_exec_file): Define.
+	* linux-low.h (class linux_process_target): Update.
+	* lynx-low.cc (lynx_target_ops): Update.
+	* nto-low.cc (nto_target_ops): Update.
+	* win32-low.cc (win32_target_ops): Update.
+
+2020-02-20  Tankut Baris Aktemur  <tankut.baris.aktemur@intel.com>
+
 	Turn process_stratum_target's supports_range_stepping op into a
 	method of process_target.
 
diff --git a/gdbserver/linux-low.cc b/gdbserver/linux-low.cc
index b780799..118aee9 100644
--- a/gdbserver/linux-low.cc
+++ b/gdbserver/linux-low.cc
@@ -6441,6 +6441,18 @@ linux_process_target::supports_range_stepping ()
   return (*the_low_target.supports_range_stepping) ();
 }
 
+bool
+linux_process_target::supports_pid_to_exec_file ()
+{
+  return true;
+}
+
+char *
+linux_process_target::pid_to_exec_file (int pid)
+{
+  return linux_proc_pid_to_exec_file (pid);
+}
+
 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
 struct target_loadseg
 {
@@ -7471,7 +7483,6 @@ linux_get_hwcap2 (int wordsize)
 static linux_process_target the_linux_target;
 
 static process_stratum_target linux_target_ops = {
-  linux_proc_pid_to_exec_file,
   linux_mntns_open_cloexec,
   linux_mntns_unlink,
   linux_mntns_readlink,
diff --git a/gdbserver/linux-low.h b/gdbserver/linux-low.h
index f47d9ed..af5892e 100644
--- a/gdbserver/linux-low.h
+++ b/gdbserver/linux-low.h
@@ -448,6 +448,10 @@ public:
 #endif
 
   bool supports_range_stepping () override;
+
+  bool supports_pid_to_exec_file () override;
+
+  char *pid_to_exec_file (int pid) override;
 };
 
 #define get_thread_lwp(thr) ((struct lwp_info *) (thread_target_data (thr)))
diff --git a/gdbserver/lynx-low.cc b/gdbserver/lynx-low.cc
index 854037a..5e23713 100644
--- a/gdbserver/lynx-low.cc
+++ b/gdbserver/lynx-low.cc
@@ -735,7 +735,6 @@ static lynx_process_target the_lynx_target;
 /* The LynxOS target_ops vector.  */
 
 static process_stratum_target lynx_target_ops = {
-  NULL,  /* pid_to_exec_file */
   NULL,  /* multifs_open */
   NULL,  /* multifs_unlink */
   NULL,  /* multifs_readlink */
diff --git a/gdbserver/nto-low.cc b/gdbserver/nto-low.cc
index 3532aa4..9a798bf 100644
--- a/gdbserver/nto-low.cc
+++ b/gdbserver/nto-low.cc
@@ -947,7 +947,6 @@ nto_sw_breakpoint_from_kind (int kind, int *size)
 static nto_process_target the_nto_target;
 
 static process_stratum_target nto_target_ops = {
-  NULL, /* pid_to_exec_file */
   NULL, /* multifs_open */
   NULL, /* multifs_unlink */
   NULL, /* multifs_readlink */
diff --git a/gdbserver/server.cc b/gdbserver/server.cc
index 61346e3..00456d8 100644
--- a/gdbserver/server.cc
+++ b/gdbserver/server.cc
@@ -1462,7 +1462,7 @@ handle_qxfer_exec_file (const char *annex,
   ULONGEST pid;
   int total_len;
 
-  if (the_target->pid_to_exec_file == NULL || writebuf != NULL)
+  if (!the_target->pt->supports_pid_to_exec_file () || writebuf != NULL)
     return -2;
 
   if (annex[0] == '\0')
@@ -1482,7 +1482,7 @@ handle_qxfer_exec_file (const char *annex,
   if (pid <= 0)
     return -1;
 
-  file = (*the_target->pid_to_exec_file) (pid);
+  file = the_target->pt->pid_to_exec_file (pid);
   if (file == NULL)
     return -1;
 
@@ -2452,7 +2452,7 @@ handle_query (char *own_buf, int packet_len, int *new_packet_len_p)
       if (target_supports_stopped_by_hw_breakpoint ())
 	strcat (own_buf, ";hwbreak+");
 
-      if (the_target->pid_to_exec_file != NULL)
+      if (the_target->pt->supports_pid_to_exec_file ())
 	strcat (own_buf, ";qXfer:exec-file:read+");
 
       strcat (own_buf, ";vContSupported+");
diff --git a/gdbserver/target.cc b/gdbserver/target.cc
index 8739ba8..3787e94 100644
--- a/gdbserver/target.cc
+++ b/gdbserver/target.cc
@@ -759,3 +759,15 @@ process_target::supports_range_stepping ()
 {
   return false;
 }
+
+bool
+process_target::supports_pid_to_exec_file ()
+{
+  return false;
+}
+
+char *
+process_target::pid_to_exec_file (int pid)
+{
+  gdb_assert_not_reached ("target op pid_to_exec_file not supported");
+}
diff --git a/gdbserver/target.h b/gdbserver/target.h
index cdb3c11..d728646 100644
--- a/gdbserver/target.h
+++ b/gdbserver/target.h
@@ -70,14 +70,6 @@ class process_target;
    shared code.  */
 struct process_stratum_target
 {
-  /* Return the full absolute name of the executable file that was
-     run to create the process PID.  If the executable file cannot
-     be determined, NULL is returned.  Otherwise, a pointer to a
-     character string containing the pathname is returned.  This
-     string should be copied into a buffer by the client if the string
-     will not be immediately used, or if it must persist.  */
-  char *(*pid_to_exec_file) (int pid);
-
   /* Multiple-filesystem-aware open.  Like open(2), but operating in
      the filesystem as it appears to process PID.  Systems where all
      processes share a common filesystem should set this to NULL.
@@ -498,6 +490,17 @@ public:
 
   /* Return true if target supports range stepping.  */
   virtual bool supports_range_stepping ();
+
+  /* Return true if the pid_to_exec_file op is supported.  */
+  virtual bool supports_pid_to_exec_file ();
+
+  /* Return the full absolute name of the executable file that was
+     run to create the process PID.  If the executable file cannot
+     be determined, NULL is returned.  Otherwise, a pointer to a
+     character string containing the pathname is returned.  This
+     string should be copied into a buffer by the client if the string
+     will not be immediately used, or if it must persist.  */
+  virtual char *pid_to_exec_file (int pid);
 };
 
 extern process_stratum_target *the_target;
diff --git a/gdbserver/win32-low.cc b/gdbserver/win32-low.cc
index b270745..3b1f7d3 100644
--- a/gdbserver/win32-low.cc
+++ b/gdbserver/win32-low.cc
@@ -1858,7 +1858,6 @@ win32_sw_breakpoint_from_kind (int kind, int *size)
 static win32_process_target the_win32_target;
 
 static process_stratum_target win32_target_ops = {
-  NULL, /* pid_to_exec_file */
   NULL, /* multifs_open */
   NULL, /* multifs_unlink */
   NULL, /* multifs_readlink */