Re: [PATCH] Improve and fix catch-syscall.exp

[Sergio Durigan Junior <sergiodj at redhat dot com>]

On Sunday, December 15 2013, Doug Evans wrote:

> I was wondering, what if the magic numbers that are the syscall
> numbers were recorded in the test .c file like:
>
> int close_syscall_number = foo;

Can you tell me what you think about this patch?

Thanks.

-- 
Sergio

2013-12-17  Sergio Durigan Junior  <sergiodj@redhat.com>

	* gdb.base/catch-syscall.c: Include <asm/unistd.h>.
	(close_syscall, chroot_syscall, exit_group_syscall): New
	variables.
	* gdb.base/catch-syscall.exp: Replace gdb_compile by
	prepare_for_testing.  Call fill_all_syscalls_numbers before
	starting.  Replace gdb_exit, gdb_start, gdb_reinitialize_dir and
	gdb_load by clean_restart.
	(check_info_bp_any_syscall, check_info_bp_specific_syscall)
	(check_info_bp_many_syscalls): Remove global gdb_prompt.
	(check_call_to_syscall): Likewise.  Add global decimal.  Improve
	testing regex.
	(check_return_from_syscall): Likewise.
	(check_continue, insert_catch_syscall_with_arg): Remove global
	gdb_prompt.
	(insert_catch_syscall_with_many_args): Likewise.  Add global
	decimal.  Fix $filter_str.  Improve testing regex.
	(check_for_program_end): Remove global gdb_prompt.
	(test_catch_syscall_without_args): Likewise.  Add global decimal.
	Improve testing regex.
	(test_catch_syscall_with_args, test_catch_syscall_with_many_args)
	(test_catch_syscall_with_wrong_args)
	(test_catch_syscall_restarting_inferior)
	(test_catch_syscall_fail_nodatadir): Remove global gdb_prompt.
	(do_syscall_tests): Likewise.  Remove global srcdir.
	(test_catch_syscall_without_args_noxml): Remove global gdb_prompt.
	Add global last_syscall_number.  Test for the exact syscall number
	to be caught.
	(test_catch_syscall_with_args_noxml): Remove global gdb_prompt.
	Add global all_syscalls_numbers.  Test each syscall number to be
	caught, instead of only testing "close".
	(test_catch_syscall_with_wrong_args_noxml): Remove global gdb_prompt.
	(do_syscall_tests_without_xml): Likewise.  Remove global srcdir.
	Remove stale comment.
	(fill_all_syscalls_numbers): Add global last_syscall_number.  Fill
	the correct syscall numbers using information from the inferior.

diff --git a/gdb/testsuite/gdb.base/catch-syscall.c b/gdb/testsuite/gdb.base/catch-syscall.c
index 64850de..a4dc10c 100644
--- a/gdb/testsuite/gdb.base/catch-syscall.c
+++ b/gdb/testsuite/gdb.base/catch-syscall.c
@@ -8,9 +8,16 @@
    September, 2008 */
 
 #include <unistd.h>
+#include <asm/unistd.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 
+/* These are the syscalls numbers used by the test.  */
+
+static int close_syscall = __NR_close;
+static int chroot_syscall = __NR_chroot;
+static int exit_group_syscall = __NR_exit_group;
+
 int
 main (void)
 {
diff --git a/gdb/testsuite/gdb.base/catch-syscall.exp b/gdb/testsuite/gdb.base/catch-syscall.exp
index 7f1bd29..c18e878 100644
--- a/gdb/testsuite/gdb.base/catch-syscall.exp
+++ b/gdb/testsuite/gdb.base/catch-syscall.exp
@@ -24,7 +24,7 @@ if { [is_remote target] || ![isnative] } then {
 }
 
 # Until "catch syscall" is implemented on other targets...
-if {![istarget "hppa*-hp-hpux*"] && ![istarget "*-linux*"]} then {
+if { ![istarget "hppa*-hp-hpux*"] && ![istarget "*-linux*"] } {
     continue
 }
 
@@ -40,26 +40,26 @@ if { ![istarget "x86_64-*-linux*"] && ![istarget "i\[34567\]86-*-linux*"]
 
 standard_testfile
 
+if  { [prepare_for_testing ${testfile}.exp $testfile ${testfile}.c] } {
+     untested catch-syscall.exp
+     return -1
+}
+
 # All (but the last) syscalls from the example code
 # They are ordered according to the file, so do not change this.
 set all_syscalls { "close" "chroot" }
 set all_syscalls_numbers { }
+
 # The last syscall (exit()) does not return, so
 # we cannot expect the catchpoint to be triggered
 # twice.  It is a special case.
 set last_syscall "exit_group"
-
-if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug}] != "" } {
-     untested catch-syscall.exp
-     return -1
-}
+set last_syscall_number { }
 
 # Internal procedure used to check if, after issuing a 'catch syscall'
 # command (without arguments), the 'info breakpoints' command displays
 # that '"any syscall"' is to be caught.
 proc check_info_bp_any_syscall {} {
-    global gdb_prompt
-
     # Verifying that the catchpoint appears in the 'info breakpoints'
     # command, but with "<any syscall>".
     set thistest "catch syscall appears in 'info breakpoints'"
@@ -70,8 +70,6 @@ proc check_info_bp_any_syscall {} {
 # command (with arguments), the 'info breakpoints' command displays
 # that the syscall 'X' is to be caught.
 proc check_info_bp_specific_syscall { syscall } {
-    global gdb_prompt
-
     set thistest "syscall(s) $syscall appears in 'info breakpoints'"
     gdb_test "info breakpoints" ".*catchpoint.*keep y.*syscall(\[(\]s\[)\])? (.)?${syscall}(.)?.*" $thistest
 }
@@ -80,7 +78,6 @@ proc check_info_bp_specific_syscall { syscall } {
 # command (with many arguments), the 'info breakpoints' command displays
 # that the syscalls 'X' are to be caught.
 proc check_info_bp_many_syscalls { syscalls } {
-    global gdb_prompt
     set filter_str ""
 
     foreach name $syscalls {
@@ -95,25 +92,23 @@ proc check_info_bp_many_syscalls { syscalls } {
 
 # This procedure checks if there was a call to a syscall.
 proc check_call_to_syscall { syscall } {
-    global gdb_prompt
+    global decimal
 
     set thistest "program has called $syscall"
-    gdb_test "continue" "Catchpoint .*(call to syscall .?${syscall}.?).*" $thistest
+    gdb_test "continue" "Catchpoint $decimal \\(call to syscall .?${syscall}.?\\).*" $thistest
 }
 
 # This procedure checks if the syscall returned.
 proc check_return_from_syscall { syscall } {
-    global gdb_prompt
+    global decimal
 
     set thistest "syscall $syscall has returned"
-    gdb_test "continue" "Catchpoint .*(returned from syscall (.)?${syscall}(.)?).*" $thistest
+    gdb_test "continue" "Catchpoint $decimal \\(returned from syscall ${syscall}\\).*" $thistest
 }
 
 # Internal procedure that performs two 'continue' commands and checks if
 # a syscall call AND return occur.
 proc check_continue { syscall } {
-    global gdb_prompt
-
     # Testing if the 'continue' stops at the
     # specified syscall_name.  If it does, then it should
     # first print that the infeior has called the syscall,
@@ -127,50 +122,48 @@ proc check_continue { syscall } {
 
 # Inserts a syscall catchpoint with an argument.
 proc insert_catch_syscall_with_arg { syscall } {
-    global gdb_prompt
+    global decimal
 
     # Trying to set the catchpoint
     set thistest "catch syscall with arguments ($syscall)"
-    gdb_test "catch syscall $syscall" "Catchpoint .*(syscall (.)?${syscall}(.)?( \[\[0-9\]+\])?).*" $thistest
+    gdb_test "catch syscall $syscall" "Catchpoint $decimal \\(syscall \'?${syscall}\'?( \[${decimal}\])?\\)" $thistest
 
     check_info_bp_specific_syscall $syscall
 }
 
 # Inserts a syscall catchpoint with many arguments.
 proc insert_catch_syscall_with_many_args { syscalls numbers } {
-    global gdb_prompt
+    global decimal
+
     set catch [ join $syscalls " " ]
     set filter_str ""
 
     foreach name $syscalls number $numbers {
-      set filter_str "${filter_str}'${name}' \[${number}\] "
+      set filter_str "${filter_str}'${name}' \\\[${number}\\\] "
     }
 
     set filter_str [ string trimright $filter_str " " ]
 
     # Trying to set the catchpoint
     set thistest "catch syscall with arguments ($filter_str)"
-    gdb_test "catch syscall $catch" "Catchpoint .*(syscalls (.)?${filter_str}(.)?).*" $thistest
+    gdb_test "catch syscall $catch" "Catchpoint $decimal \\(syscalls ${filter_str}\\).*" $thistest
 
     check_info_bp_many_syscalls $syscalls
 }
 
 proc check_for_program_end {} {
-    global gdb_prompt
-
     # Deleting the catchpoints
     delete_breakpoints
 
     gdb_continue_to_end
-
 }
 
 proc test_catch_syscall_without_args {} {
-    global gdb_prompt all_syscalls last_syscall
+    global all_syscalls last_syscall decimal
 
     with_test_prefix "without arguments" {
 	# Trying to set the syscall.
-	gdb_test "catch syscall" "Catchpoint .*(syscall).*"
+	gdb_test "catch syscall" "Catchpoint $decimal \\(any syscall\\)"
 
 	check_info_bp_any_syscall
 
@@ -190,8 +183,6 @@ proc test_catch_syscall_without_args {} {
 
 proc test_catch_syscall_with_args {} {
     with_test_prefix "with arguments" {
-	global gdb_prompt
-
 	set syscall_name "close"
 	insert_catch_syscall_with_arg $syscall_name
 
@@ -205,7 +196,7 @@ proc test_catch_syscall_with_args {} {
 
 proc test_catch_syscall_with_many_args {} {
     with_test_prefix "with many arguments" {
-	global gdb_prompt all_syscalls all_syscalls_numbers
+	global all_syscalls all_syscalls_numbers
 
 	insert_catch_syscall_with_many_args $all_syscalls $all_syscalls_numbers
 
@@ -221,8 +212,6 @@ proc test_catch_syscall_with_many_args {} {
 
 proc test_catch_syscall_with_wrong_args {} {
     with_test_prefix "wrong args" {
-	global gdb_prompt
-
 	# mlock is not called from the source
 	set syscall_name "mlock"
 	insert_catch_syscall_with_arg $syscall_name
@@ -237,8 +226,6 @@ proc test_catch_syscall_with_wrong_args {} {
 
 proc test_catch_syscall_restarting_inferior {} {
     with_test_prefix "restarting inferior" {
-	global gdb_prompt
-
 	set syscall_name "chroot"
 
 	with_test_prefix "entry" {
@@ -263,8 +250,6 @@ proc test_catch_syscall_restarting_inferior {} {
 
 proc test_catch_syscall_fail_nodatadir {} {
     with_test_prefix "fail no datadir" {
-	global gdb_prompt
-
 	# Sanitizing.
 	delete_breakpoints
 
@@ -289,8 +274,6 @@ proc test_catch_syscall_fail_nodatadir {} {
 }
 
 proc do_syscall_tests {} {
-    global gdb_prompt srcdir
-
     # NOTE: We don't have to point gdb at the correct data-directory.
     # For the build tree that is handled by INTERNAL_GDBFLAGS.
 
@@ -332,7 +315,7 @@ proc test_catch_syscall_without_args_noxml {} {
     with_test_prefix "without args noxml" {
 	# We will need the syscall names even not using it because we
 	# need to know know many syscalls are in the example file.
-	global gdb_prompt all_syscalls last_syscall
+	global all_syscalls last_syscall_number all_syscalls_numbers
 
 	delete_breakpoints
 
@@ -340,19 +323,15 @@ proc test_catch_syscall_without_args_noxml {} {
 
 	# Now, we should be able to set a catchpoint, and GDB shall
 	# not display the warning anymore.
-	foreach name $all_syscalls {
-	    # Unfortunately, we don't know the syscall number that
-	    # will be caught because this information is
-	    # arch-dependent.  Thus, we try to catch anything similar
-	    # to a number.
+	foreach name $all_syscalls number $all_syscalls_numbers {
 	    with_test_prefix "$name" {
-		check_continue "\[0-9\]*"
+		check_continue $number
 	    }
 	}
 
 	# At last but not least, we check if the inferior has called
 	# the last (exit) syscall.
-	check_call_to_syscall "\[0-9\]*"
+	check_call_to_syscall $last_syscall_number
 
 	delete_breakpoints
     }
@@ -360,25 +339,19 @@ proc test_catch_syscall_without_args_noxml {} {
 
 proc test_catch_syscall_with_args_noxml {} {
     with_test_prefix "with args noxml" {
-	global gdb_prompt
-
-	# The number of the "close" syscall.  This is our option for a
-	# "long-estabilished" syscall in all Linux architectures, but
-	# unfortunately x86_64 and a few other platforms don't "follow
-	# the convention".  Because of this, we need this ugly check
-	# :-(.
-	set close_number ""
-	if { [istarget "x86_64-*-linux*"] } {
-	    set close_number "3"
-	} else {
-	    set close_number "6"
-	}
+	global all_syscalls_numbers
 
 	delete_breakpoints
 
-	insert_catch_syscall_with_arg $close_number
+	# Inserting all syscalls numbers to be caught
+	foreach syscall_number $all_syscalls_numbers {
+	    insert_catch_syscall_with_arg $syscall_number
+	}
 
-	check_continue $close_number
+	# Checking that all syscalls are caught.
+	foreach syscall_number $all_syscalls_numbers {
+	    check_continue $syscall_number
+	}
 
 	delete_breakpoints
     }
@@ -386,8 +359,6 @@ proc test_catch_syscall_with_args_noxml {} {
 
 proc test_catch_syscall_with_wrong_args_noxml {} {
     with_test_prefix "with wrong args noxml" {
-	global gdb_prompt
-
 	delete_breakpoints
 
 	# Even without XML support, GDB should not accept unknown
@@ -400,8 +371,6 @@ proc test_catch_syscall_with_wrong_args_noxml {} {
 }
 
 proc do_syscall_tests_without_xml {} {
-    global gdb_prompt srcdir
-
     # Make sure GDB doesn't load the syscalls xml from the system data
     # directory.
     gdb_test_no_output "set data-directory /the/path/to/nowhere"
@@ -413,12 +382,6 @@ proc do_syscall_tests_without_xml {} {
     # The only valid argument "catch syscall" should accept is the
     # syscall number, and not the name (since it can't translate a
     # name to a number).
-    #
-    # It's worth mentioning that we only try to catch the syscall
-    # close().  This is because the syscall number is an arch-dependent
-    # information, so we can't assume that we know every syscall number
-    # in this system.  Therefore, we have decided to use a "long-estabilished"
-    # system call, and close() just sounded the right choice :-).
     if [runto_main] then { test_catch_syscall_with_args_noxml }
 
     # Now, we'll try to provide a syscall name (valid or not) to the command,
@@ -428,47 +391,35 @@ proc do_syscall_tests_without_xml {} {
 
 # This procedure fills the vector "all_syscalls_numbers" with the proper
 # numbers for the used syscalls according to the architecture.
+#
+# These numbers were taken from the respective <asm/unistd.h> files
+# from each architecture.
 proc fill_all_syscalls_numbers {} {
-    global all_syscalls_numbers
-
-    # For Linux on x86, PPC, PPC64, SPARC, SPARC64 and ARM,
-    # the numbers for the syscalls "close" and "chroot" are the same.
-    if { [istarget "i\[34567\]86-*-linux*"]
-         || [istarget "powerpc-*-linux*"] || [istarget "powerpc64-*-linux*"]
-         || [istarget "sparc-*-linux*"] || [istarget "sparc64-*-linux*"]
-         || [istarget "arm*-linux*"] } {
-         set all_syscalls_numbers { "6" "61" }
-    }
-}
+    global all_syscalls_numbers last_syscall_number
 
-# Start with a fresh gdb
+    set close_syscall [get_integer_valueof "close_syscall" 0]
+    set chroot_syscall [get_integer_valueof "chroot_syscall" 0]
+    set all_syscalls_numbers [list $close_syscall $chroot_syscall]
+    set last_syscall_number [get_integer_valueof "exit_group_syscall" 0]
+}
 
-gdb_exit
-set do_xml_test ![gdb_skip_xml_test]
-gdb_start
-gdb_reinitialize_dir $srcdir/$subdir
-gdb_load ${binfile}
+# Filling all the syscalls numbers before starting anything.
+fill_all_syscalls_numbers
 
 # Execute the tests, using XML support
-if $do_xml_test {
+if { ![gdb_skip_xml_test] } {
+  clean_restart $binfile
   do_syscall_tests
 
   # Now, we have to see if GDB displays a warning when we
   # don't set the data-directory but try to use catch syscall
   # anyway.  For that, we must restart GDB first.
-  gdb_exit
-  gdb_start
-  gdb_reinitialize_dir $srcdir/$subdir
-  gdb_load ${binfile}
+  clean_restart $binfile
   test_catch_syscall_fail_nodatadir
 }
 
 # Restart gdb
-
-gdb_exit
-gdb_start
-gdb_reinitialize_dir $srcdir/$subdir
-gdb_load ${binfile}
+clean_restart $binfile
 
 # Execute the tests, without XML support.  In this case, GDB will
 # only display syscall numbers, and not syscall names.