gdb: add remote_debug_printf

This is the next in the new-style debug macro series.

For this one, I decided to omit the function name from the "Sending packet" /
"Packet received" kind of prints, just because it's not very useful in that
context and hinders readability more than anything else.  This is completely
arbitrary.

This is with:

  [remote] putpkt_binary: Sending packet: $qTStatus#49...
  [remote] getpkt_or_notif_sane_1: Packet received: T0;tnotrun:0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:0;stoptime:0;username:;notes::

and without:

  [remote] Sending packet: $qTStatus#49...
  [remote] Packet received: T0;tnotrun:0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:0;stoptime:0;username:;notes::

A difference is that previously, the query packet and its reply would be
printed on the same line, like this:

  Sending packet: $qTStatus#49...Packet received: T0;tnotrun:0;tframes:0;tcreated:0;tfree:500000;tsize:500000;circular:0;disconn:0;starttime:0;stoptime:0;username:;notes::

Now, they are printed on two lines, since each remote_debug_printf{,_nofunc}
prints its own complete message including an end of line.  It's probably
a matter of taste, but I prefer the two-line version, it's easier to
follow, especially when the query packet is long.

As a result, lib/range-stepping-support.exp needs to be updated, as it
currently expects the vCont packet and the reply to be on the same line.
I think it's sufficient in that context to just expect the vCont packet
and not the reply, since the goal is just to count how many vCont;r GDB
sends.

gdb/ChangeLog:

	* remote.h (remote_debug_printf): New.
	(remote_debug_printf_nofunc): New.
	(REMOTE_SCOPED_DEBUG_ENTER_EXIT): New.
	* remote.c: Use above macros throughout file.

gdbsupport/ChangeLog:

	* common-debug.h (debug_prefixed_printf_cond_nofunc): New.
	* common-debug.c (debug_prefixed_vprintf): Handle a nullptr
	func.

gdb/testsuite/ChangeLog:

	* lib/range-stepping-support.exp (exec_cmd_expect_vCont_count):
	Adjust to "set debug remote" changes.

Change-Id: Ica6dead50d3f82e855c7d763f707cef74bed9fee

3 files changed, 19 insertions, 1 deletions

diff --git a/gdbsupport/ChangeLog b/gdbsupport/ChangeLog
index d973a6daa4f..487107e3b14 100644
--- a/gdbsupport/ChangeLog
+++ b/gdbsupport/ChangeLog
@@ -1,3 +1,9 @@
+2021-01-22  Simon Marchi  <simon.marchi@polymtl.ca>
+
+	* common-debug.h (debug_prefixed_printf_cond_nofunc): New.
+	* common-debug.c (debug_prefixed_vprintf): Handle a nullptr
+	func.
+
 2021-01-08  Simon Marchi  <simon.marchi@polymtl.ca>
 
 	PR gdb/27157
diff --git a/gdbsupport/common-debug.cc b/gdbsupport/common-debug.cc
index 0d3e9198921..39474c2c860 100644
--- a/gdbsupport/common-debug.cc
+++ b/gdbsupport/common-debug.cc
@@ -55,7 +55,11 @@ void
 debug_prefixed_vprintf (const char *module, const char *func,
 			const char *format, va_list args)
 {
-  debug_printf ("%*s[%s] %s: ", debug_print_depth * 2, "", module, func);
+  if (func != nullptr)
+    debug_printf ("%*s[%s] %s: ", debug_print_depth * 2, "", module, func);
+  else
+    debug_printf ("%*s[%s] ", debug_print_depth * 2, "", module);
+
   debug_vprintf (format, args);
   debug_printf ("\n");
 }
diff --git a/gdbsupport/common-debug.h b/gdbsupport/common-debug.h
index f3137870ffc..05367401a7d 100644
--- a/gdbsupport/common-debug.h
+++ b/gdbsupport/common-debug.h
@@ -66,6 +66,14 @@ extern void ATTRIBUTE_PRINTF (3, 0) debug_prefixed_vprintf
     } \
   while (0)
 
+#define debug_prefixed_printf_cond_nofunc(debug_enabled_cond, module, fmt, ...) \
+  do \
+    { \
+      if (debug_enabled_cond) \
+	debug_prefixed_printf (module, nullptr, fmt, ##__VA_ARGS__); \
+    } \
+  while (0)
+
 /* Nesting depth of scoped_debug_start_end objects.  */
 
 extern int debug_print_depth;