Add "info connections" command, "info inferiors" connection number/string

This commit extends the CLI a bit for multi-target, in three ways.

#1 - New "info connections" command.

This is a new command that lists the open connections (process_stratum
targets).  For example, if you're debugging two remote connections, a
couple local/native processes, and a core dump, all at the same time,
you might see something like this:

 (gdb) info connections
   Num  What                     Description
   1    remote 192.168.0.1:9999  Remote serial target in gdb-specific protocol
   2    remote 192.168.0.2:9998  Remote serial target in gdb-specific protocol
 * 3    native                   Native process
   4    core                     Local core dump file

#2 - New "info inferiors" "Connection" column

You'll also see a new matching "Connection" column in "info
inferiors", showing you which connection an inferior is bound to:

 (gdb) info inferiors
   Num  Description       Connection                   Executable
   1    process 18526     1 (remote 192.168.0.1:9999)  target:/tmp/a.out
   2    process 18531     2 (remote 192.168.0.2:9998)  target:/tmp/a.out
   3    process 19115     3 (native)                   /tmp/prog1
   4    process 6286      4 (core)                     myprogram
 * 5    process 19122     3 (native)                   /bin/hello

#3 - Makes "add-inferior" show the inferior's target connection

"add-inferior" now shows you the connection you've just bound the
inferior to, which is the current process_stratum target:

 (gdb) add-inferior
 [New inferior 2]
 Added inferior 2 on connection 1 (extended-remote localhost:2346)

gdb/ChangeLog:
2020-01-10  Pedro Alves  <palves@redhat.com>

	* Makefile.in (COMMON_SFILES): Add target-connection.c.
	* inferior.c (uiout_field_connection): New function.
	(print_inferior): Add new "connection-id" column.
	(add_inferior_command): Show connection number/string of added
	inferior.
	* process-stratum-target.h
	(process_stratum_target::connection_string): New virtual method.
	(process_stratum_target::connection_number): New field.
	* remote.c (remote_target::connection_string): New override.
	* target-connection.c: New file.
	* target-connection.h: New file.
	* target.c (decref_target): Remove process_stratum targets from
	the connection list.
	(target_stack::push): Add process_stratum targets to the
	connection list.

gdb/testsuite/ChangeLog:
2020-01-10  Pedro Alves  <palves@redhat.com>

	* gdb.base/kill-detach-inferiors-cmd.exp: Adjust expected output
	of "add-inferior".
	* gdb.base/quit-live.exp: Likewise.
	* gdb.base/remote-exec-file.exp: Likewise.
	* gdb.guile/scm-progspace.exp: Likewise.
	* gdb.linespec/linespec.exp: Likewise.
	* gdb.mi/new-ui-mi-sync.exp: Likewise.
	* gdb.mi/user-selected-context-sync.exp: Likewise.
	* gdb.multi/multi-target.exp (setup): Add "info connection" and
	"info inferiors" tests.
	* gdb.multi/remove-inferiors.exp: Adjust expected output of
	"add-inferior".
	* gdb.multi/watchpoint-multi.exp: Likewise.
	* gdb.python/py-inferior.exp: Likewise.
	* gdb.server/extended-remote-restart.exp: Likewise.
	* gdb.threads/fork-plus-threads.exp: Adjust expected output of
	"info inferiors".
	* gdb.threads/forking-threads-plus-breakpoint.exp: Likewise.
	* gdb.trace/report.exp: Likewise.

16 files changed, 75 insertions, 23 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 9297fa2..e7bd05a 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,27 @@
 2020-01-10  Pedro Alves  <palves@redhat.com>
 
+	* gdb.base/kill-detach-inferiors-cmd.exp: Adjust expected output
+	of "add-inferior".
+	* gdb.base/quit-live.exp: Likewise.
+	* gdb.base/remote-exec-file.exp: Likewise.
+	* gdb.guile/scm-progspace.exp: Likewise.
+	* gdb.linespec/linespec.exp: Likewise.
+	* gdb.mi/new-ui-mi-sync.exp: Likewise.
+	* gdb.mi/user-selected-context-sync.exp: Likewise.
+	* gdb.multi/multi-target.exp (setup): Add "info connection" and
+	"info inferiors" tests.
+	* gdb.multi/remove-inferiors.exp: Adjust expected output of
+	"add-inferior".
+	* gdb.multi/watchpoint-multi.exp: Likewise.
+	* gdb.python/py-inferior.exp: Likewise.
+	* gdb.server/extended-remote-restart.exp: Likewise.
+	* gdb.threads/fork-plus-threads.exp: Adjust expected output of
+	"info inferiors".
+	* gdb.threads/forking-threads-plus-breakpoint.exp: Likewise.
+	* gdb.trace/report.exp: Likewise.
+
+2020-01-10  Pedro Alves  <palves@redhat.com>
+
 	* gdb.multi/multi-target.c: New file.
 	* gdb.multi/multi-target.exp: New file.
 	* lib/gdbserver-support.exp (gdb_target_cmd): Handle "Non-stop
diff --git a/gdb/testsuite/gdb.base/kill-detach-inferiors-cmd.exp b/gdb/testsuite/gdb.base/kill-detach-inferiors-cmd.exp
index 600de9c..82e0c71 100644
--- a/gdb/testsuite/gdb.base/kill-detach-inferiors-cmd.exp
+++ b/gdb/testsuite/gdb.base/kill-detach-inferiors-cmd.exp
@@ -32,7 +32,7 @@ if [prepare_for_testing "failed to prepare" $executable] {
 runto_main
 
 # Add another forked inferior process.
-gdb_test "add-inferior" "Added inferior 2" "add inferior 2"
+gdb_test "add-inferior" "Added inferior 2 on connection .*" "add inferior 2"
 gdb_test "inferior 2" "Switching to inferior 2.*"
 gdb_test "file $binfile" "Reading symbols from .*" "load binary"
 gdb_test "start" "Temporary breakpoint.*Starting program.*"
@@ -40,7 +40,7 @@ gdb_test "start" "Temporary breakpoint.*Starting program.*"
 # Add an attached inferior process.
 set test_spawn_id [spawn_wait_for_attach $binfile]
 set test_pid [spawn_id_get_pid $test_spawn_id]
-gdb_test "add-inferior" "Added inferior 3" "add inferior 3"
+gdb_test "add-inferior" "Added inferior 3 on connection .*" "add inferior 3"
 gdb_test "inferior 3" "Switching to inferior 3.*"
 gdb_test "attach $test_pid" "Attaching to process.*" "attach to pid"
 
diff --git a/gdb/testsuite/gdb.base/quit-live.exp b/gdb/testsuite/gdb.base/quit-live.exp
index 109c5e9..c8e2f01 100644
--- a/gdb/testsuite/gdb.base/quit-live.exp
+++ b/gdb/testsuite/gdb.base/quit-live.exp
@@ -120,7 +120,7 @@ proc quit_with_live_inferior {appear_how extra_inferior quit_how} {
     }
 
     if {$extra_inferior} {
-	gdb_test "add-inferior" "Added inferior 2*" \
+	gdb_test "add-inferior" "Added inferior 2 on connection .*" \
 	    "add empty inferior 2"
 	gdb_test "inferior 2" "Switching to inferior 2.*" \
 	    "switch to inferior 2"
diff --git a/gdb/testsuite/gdb.base/remote-exec-file.exp b/gdb/testsuite/gdb.base/remote-exec-file.exp
index 277e405..a479a79 100644
--- a/gdb/testsuite/gdb.base/remote-exec-file.exp
+++ b/gdb/testsuite/gdb.base/remote-exec-file.exp
@@ -27,7 +27,7 @@ with_test_prefix "set inf 1" {
 
 # Set remote exec-file in inferior 2.
 with_test_prefix "set inf 2" {
-    gdb_test "add-inferior" "Added inferior 2" "add inferior 2"
+    gdb_test "add-inferior" "Added inferior 2.*" "add inferior 2"
     gdb_test "inferior 2" "Switching to inferior 2.*"
     gdb_test_no_output "set remote exec-file prog2"
 }
diff --git a/gdb/testsuite/gdb.guile/scm-progspace.exp b/gdb/testsuite/gdb.guile/scm-progspace.exp
index 9b89ef4..91a78e2 100644
--- a/gdb/testsuite/gdb.guile/scm-progspace.exp
+++ b/gdb/testsuite/gdb.guile/scm-progspace.exp
@@ -73,7 +73,7 @@ with_test_prefix "program unloaded" {
 # deleted.  We need to, for example, delete an inferior to get the progspace
 # to go away.
 
-gdb_test "add-inferior" "Added inferior 2" "create new inferior"
+gdb_test "add-inferior" "Added inferior 2.*" "create new inferior"
 gdb_test "inferior 2" ".*" "switch to new inferior"
 gdb_test_no_output "remove-inferiors 1" "remove first inferior"
 
diff --git a/gdb/testsuite/gdb.linespec/linespec.exp b/gdb/testsuite/gdb.linespec/linespec.exp
index 38f1cf0..be1b918 100644
--- a/gdb/testsuite/gdb.linespec/linespec.exp
+++ b/gdb/testsuite/gdb.linespec/linespec.exp
@@ -201,7 +201,7 @@ gdb_test "break lspec.h:$line" \
 # Multi-inferior tests.
 #
 
-gdb_test "add-inferior" "Added inferior 2" \
+gdb_test "add-inferior" "Added inferior 2.*" \
     "add inferior for linespec tests"
 
 gdb_test "inferior 2" "Switching to inferior 2 .*" \
diff --git a/gdb/testsuite/gdb.mi/new-ui-mi-sync.exp b/gdb/testsuite/gdb.mi/new-ui-mi-sync.exp
index b94f3f9..a55fae6 100644
--- a/gdb/testsuite/gdb.mi/new-ui-mi-sync.exp
+++ b/gdb/testsuite/gdb.mi/new-ui-mi-sync.exp
@@ -83,7 +83,7 @@ proc do_test {sync_command} {
     # in the separate MI UI.  Note the "run" variant usually triggers
     # =thread-group-started/=thread-created/=library-loaded as well.
     with_spawn_id $gdb_main_spawn_id {
-	gdb_test "add-inferior" "Added inferior 2"
+	gdb_test "add-inferior" "Added inferior 2 on connection .*"
     }
 
     # Interrupt the program.
diff --git a/gdb/testsuite/gdb.mi/user-selected-context-sync.exp b/gdb/testsuite/gdb.mi/user-selected-context-sync.exp
index 8a752b0..390df00 100644
--- a/gdb/testsuite/gdb.mi/user-selected-context-sync.exp
+++ b/gdb/testsuite/gdb.mi/user-selected-context-sync.exp
@@ -415,7 +415,7 @@ proc_with_prefix test_setup { mode } {
 	# Add the second inferior now.  While this is not mandatory, it allows
 	# us to assume that per-inferior thread numbering will be used,
 	# simplifying test_continue_to_start a bit (Thread 1.2 and not Thread 2).
-	gdb_test "add-inferior" "Added inferior 2" "add inferior 2"
+	gdb_test "add-inferior" "Added inferior 2 on connection .*" "add inferior 2"
 
 	# Prepare the first inferior for the test.
 	test_continue_to_start $mode 1
diff --git a/gdb/testsuite/gdb.multi/multi-target.exp b/gdb/testsuite/gdb.multi/multi-target.exp
index cd0db12..903831c 100644
--- a/gdb/testsuite/gdb.multi/multi-target.exp
+++ b/gdb/testsuite/gdb.multi/multi-target.exp
@@ -137,8 +137,34 @@ proc setup {non-stop} {
 	return 0
     }
 
+    set ws "\[ \t\]+"
+    global decimal
+
+    # Test "info connections" and "info inferior"'s "Connection"
+    # column, while at it.
+
+    gdb_test "info connections" \
+	[multi_line \
+	     "Num${ws}What${ws}Description${ws}" \
+	     "  1${ws}native${ws}Native process${ws}" \
+	     "  2${ws}extended-remote localhost:$decimal${ws}Extended remote serial target in gdb-specific protocol${ws}" \
+	     "  3${ws}core${ws}Local core dump file${ws}" \
+	     "  4${ws}extended-remote localhost:$decimal${ws}Extended remote serial target in gdb-specific protocol${ws}" \
+	   "\\* 5${ws}core${ws}Local core dump file${ws}" \
+	    ]
+
+    gdb_test "info inferiors" \
+	[multi_line \
+	     "Num${ws}Description${ws}Connection${ws}Executable${ws}" \
+	     "  1${ws}process ${decimal}${ws}1 \\(native\\)${ws}${binfile}${ws}" \
+	     "  2${ws}process ${decimal}${ws}2 \\(extended-remote localhost:$decimal\\)${ws}${binfile}${ws}" \
+	     "  3${ws}process ${decimal}${ws}3 \\(core\\)${ws}${binfile}${ws}" \
+	     "  4${ws}process ${decimal}${ws}1 \\(native\\)${ws}${binfile}${ws}" \
+	     "  5${ws}process ${decimal}${ws}4 \\(extended-remote localhost:$decimal\\)${ws}${binfile}${ws}" \
+	   "\\* 6${ws}process ${decimal}${ws}5 \\(core\\)${ws}${binfile}${ws}" \
+	    ]
+
     # For debugging.
-    gdb_test "info inferiors" ".*"
     gdb_test "info threads" ".*"
 
     # Make "continue" resume all inferiors.
diff --git a/gdb/testsuite/gdb.multi/remove-inferiors.exp b/gdb/testsuite/gdb.multi/remove-inferiors.exp
index 27a94b8..54c2c00 100644
--- a/gdb/testsuite/gdb.multi/remove-inferiors.exp
+++ b/gdb/testsuite/gdb.multi/remove-inferiors.exp
@@ -26,7 +26,7 @@ proc switch_to_inferior { num message } {
 }
 
 proc add_inferior { expected_num message } {
-    gdb_test "add-inferior" "Added inferior ${expected_num}" "${message}"
+    gdb_test "add-inferior" "Added inferior ${expected_num}( on connection .*)?" "${message}"
 }
 
 proc test_remove_inferiors { } {
diff --git a/gdb/testsuite/gdb.multi/watchpoint-multi.exp b/gdb/testsuite/gdb.multi/watchpoint-multi.exp
index 4ff24ee..2d48b70 100644
--- a/gdb/testsuite/gdb.multi/watchpoint-multi.exp
+++ b/gdb/testsuite/gdb.multi/watchpoint-multi.exp
@@ -53,7 +53,7 @@ if [support_displaced_stepping] {
 gdb_breakpoint main {temporary}
 gdb_test "run" "Temporary breakpoint.* main .*" "start to main inferior 1"
 
-gdb_test "add-inferior" "Added inferior 2" "add inferior 2"
+gdb_test "add-inferior" "Added inferior 2 on connection .*" "add inferior 2"
 gdb_test "inferior 2" "witching to inferior 2 .*" "switch to inferior 2, first time"
 gdb_load $binfile
 
diff --git a/gdb/testsuite/gdb.python/py-inferior.exp b/gdb/testsuite/gdb.python/py-inferior.exp
index a9a36b4..997da19 100644
--- a/gdb/testsuite/gdb.python/py-inferior.exp
+++ b/gdb/testsuite/gdb.python/py-inferior.exp
@@ -279,7 +279,7 @@ with_test_prefix "selected_inferior" {
     gdb_test "inferior 1" ".*" "switch to first inferior"
     gdb_test "py print (gdb.selected_inferior().num)" "1" "first inferior selected"
 
-    gdb_test "add-inferior" "Added inferior 3" "create new inferior"
+    gdb_test "add-inferior" "Added inferior 3 on connection .*" "create new inferior"
     gdb_test "inferior 3" ".*" "switch to third inferior"
     gdb_test "py print (gdb.selected_inferior().num)" "3" "third inferior selected"
     gdb_test "inferior 1" ".*" "switch back to first inferior"
@@ -288,7 +288,7 @@ with_test_prefix "selected_inferior" {
 
 # Test repr()/str()
 with_test_prefix "__repr__" {
-    gdb_test "add-inferior" "Added inferior 4" "add inferior 4"
+    gdb_test "add-inferior" "Added inferior 4 on connection .*" "add inferior 4"
     gdb_py_test_silent_cmd "python infs = gdb.inferiors()" "get inferior list" 1
     gdb_test "python print (infs\[0\])" "<gdb.Inferior num=1, pid=$decimal>"
     gdb_test "python print (infs)" \
diff --git a/gdb/testsuite/gdb.server/extended-remote-restart.exp b/gdb/testsuite/gdb.server/extended-remote-restart.exp
index 3ce0f0b..11f8a28 100644
--- a/gdb/testsuite/gdb.server/extended-remote-restart.exp
+++ b/gdb/testsuite/gdb.server/extended-remote-restart.exp
@@ -88,12 +88,16 @@ proc test_reload { do_kill_p follow_child_p } {
     gdb_breakpoint "breakpt"
     gdb_continue_to_breakpoint "breakpt"
 
-    # Check we have the expected inferiors.
+    set ws "\[ \t\]+"
+    set any_re "\[^\r\n\]+"
+    set connection_re $any_re
+    set executable_re $any_re
+
     gdb_test "info inferiors" \
 	[multi_line \
-	     "  Num  Description       Executable.*" \
-	     "${parent_prefix} 1 +${live_inf_ptn} \[^\r\n\]+" \
-	     "${child_prefix} 2 +${live_inf_ptn} \[^\r\n\]+" ] \
+	     "  Num${ws}Description${ws}Connection${ws}Executable${ws}" \
+	     "${parent_prefix} 1${ws}${live_inf_ptn}${ws}${connection_re}${executable_re}" \
+	     "${child_prefix} 2${ws}${live_inf_ptn}${ws}${connection_re}${executable_re}" ] \
 	"Check inferiors at breakpoint"
 
     if { $do_kill_p } {
@@ -107,9 +111,9 @@ proc test_reload { do_kill_p follow_child_p } {
 	# Check the first inferior really did die.
 	gdb_test "info inferiors" \
 	    [multi_line \
-		 "  Num  Description       Executable.*" \
-		 "${parent_prefix} 1 +${parent_inf_after_kill_ptn} \[^\r\n\]+" \
-		 "${child_prefix} 2 +${child_inf_after_kill_ptn} \[^\r\n\]+" ] \
+		 "  Num${ws}Description${ws}Connection${ws}Executable${ws}" \
+		 "${parent_prefix} 1${ws}${parent_inf_after_kill_ptn}${ws}${connection_re}${executable_re}" \
+		 "${child_prefix} 2${ws}${child_inf_after_kill_ptn}${ws}${connection_re}${executable_re}" ] \
 	    "Check inferior was killed"
     }
 
diff --git a/gdb/testsuite/gdb.threads/fork-plus-threads.exp b/gdb/testsuite/gdb.threads/fork-plus-threads.exp
index 9db964a..8d36b96 100644
--- a/gdb/testsuite/gdb.threads/fork-plus-threads.exp
+++ b/gdb/testsuite/gdb.threads/fork-plus-threads.exp
@@ -109,7 +109,7 @@ proc do_test { detach_on_fork } {
 	"no threads left"
 
     gdb_test "info inferiors" \
-	"Num\[ \t\]+Description\[ \t\]+Executable\[ \t\]+\r\n\\* 1 \[^\r\n\]+" \
+	"Num\[ \t\]+Description\[ \t\]+Connection\[ \t\]+Executable\[ \t\]+\r\n\\* 1 \[^\r\n\]+" \
 	"only inferior 1 left"
 }
 
diff --git a/gdb/testsuite/gdb.threads/forking-threads-plus-breakpoint.exp b/gdb/testsuite/gdb.threads/forking-threads-plus-breakpoint.exp
index 17efbc7..c4c9596 100644
--- a/gdb/testsuite/gdb.threads/forking-threads-plus-breakpoint.exp
+++ b/gdb/testsuite/gdb.threads/forking-threads-plus-breakpoint.exp
@@ -142,7 +142,7 @@ proc do_test { cond_bp_target detach_on_fork displaced } {
 	"no threads left"
 
     gdb_test "info inferiors" \
-	"Num\[ \t\]+Description\[ \t\]+Executable\[ \t\]+\r\n\\* 1 \[^\r\n\]+" \
+	"Num\[ \t\]+Description\[ \t\]+Connection\[ \t\]+Executable\[ \t\]+\r\n\\* 1 \[^\r\n\]+" \
 	"only inferior 1 left"
 }
 
diff --git a/gdb/testsuite/gdb.trace/report.exp b/gdb/testsuite/gdb.trace/report.exp
index 05ccc04..9302975 100644
--- a/gdb/testsuite/gdb.trace/report.exp
+++ b/gdb/testsuite/gdb.trace/report.exp
@@ -391,7 +391,7 @@ proc use_collected_data { data_source } {
 	# There is always a thread of an inferior, either a live one or
 	# a faked one.
 	gdb_test "info threads" "\\* ${decimal}    (process|Thread) \[0-9\.\]+\[ \t\].*"
-	gdb_test "info inferiors" "\\* 1    process ${decimal} \[ \t\]+${binfile}.*"
+	gdb_test "info inferiors" "\\* 1    process ${decimal} \[ \t\]+\[^\r\n\]*\[ \t\]+${binfile}.*"
     }
 }