[PATCH v2 1/2] [gdb/testsuite] Simplify core_find

[Tom de Vries <tdevries@suse.de>]

In proc core_find we have:
...
catch "system \"(cd ${coredir}; ulimit -c unlimited; $coredump_filter_cmd; ${binfile} ${arg}; true) >${output_file} 2>&1\""
...

We can rewrite this into something more readable with less quote and escape
magic:
...
set arg [subst -nocommands -novariables $arg]
set cmd [subst_vars {
    (cd ${coredir};
     ulimit -c unlimited;
     $coredump_filter_cmd;
     ${binfile} ${arg};
     true) \
        >${output_file} 2>&1}]
catch {
    system $cmd
}
...

The "set arg [subst ... $arg]" is a bit awkward, and dropping it allows us to
update test-case gdb.base/corefile-exec-context.exp to use a bit more typical
setup with string_to_regex.

Note that what is being tested hasn't changed.

We can print the effective value of arg by adding to the command passed to
system.  Without this patch using:
...
echo \\\"$arg\\\;
...
and with this patch using:
...
echo "$arg";
...
and in both cases we get:
...
aaaaa bbbbb ccccc ddddd e\ e\ e\ e\ e
...
---
 .../gdb.base/corefile-exec-context.exp        | 13 +++++++---
 gdb/testsuite/lib/gdb.exp                     | 26 ++++++++++++++++---
 2 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/gdb/testsuite/gdb.base/corefile-exec-context.exp b/gdb/testsuite/gdb.base/corefile-exec-context.exp
index 9b018533b68..56c68a6a5cd 100644
--- a/gdb/testsuite/gdb.base/corefile-exec-context.exp
+++ b/gdb/testsuite/gdb.base/corefile-exec-context.exp
@@ -69,7 +69,7 @@ gdb_test_multiple "core-file $corefile_1" "load core file no args" {
 }
 
 # Generate a core file, this time pass some arguments to the inferior.
-set args "aaaaa bbbbb ccccc ddddd e\\\\ e\\\\ e\\\\ e\\\\ e"
+set args {aaaaa bbbbb ccccc ddddd e\ e\ e\ e\ e}
 set corefile [core_find $binfile {} $args]
 if {$corefile == ""} {
     untested "unable to create corefile"
@@ -82,8 +82,11 @@ remote_exec build "mv $corefile $corefile_2"
 # argument list are seen.
 clean_restart $testfile
 set saw_generated_line false
+set re_args [string_to_regexp $args]
+set re_cmd "[string_to_regexp $binfile] $re_args"
+set re_line [subst_vars {^Core was generated by `$re_cmd'\.\r\n}]
 gdb_test_multiple "core-file $corefile_2" "load core file with args" {
-    -re "^Core was generated by `[string_to_regexp $binfile] $args'\\.\r\n" {
+    -re $re_line {
 	set saw_generated_line true
 	exp_continue
     }
@@ -99,7 +102,8 @@ gdb_test_multiple "core-file $corefile_2" "load core file with args" {
 
 # Also, the argument list should be available through 'show args'.
 gdb_test "show args" \
-    "Argument list to give program being debugged when it is started is \"$args\"\\."
+    [subst_vars \
+	 {Argument list to give program being debugged when it is started is "$re_args"\.}]
 
 # Move up to 'main'.  Do it this way because we cannot know how many
 # frames up 'main' actually is.
@@ -178,8 +182,9 @@ proc check_for_env_var { var_name var_value } {
 gdb_assert { ![check_for_env_var $env_var_name $env_var_value] } \
     "environment variable is not set before core file load"
 
+set re_cmd "[string_to_regexp $binfile] $re_args"
 gdb_test "core-file $corefile_3" \
-    "Core was generated by `[string_to_regexp $binfile] $args'\\.\r\n.*" \
+    [subst_vars {Core was generated by `$re_cmd'\.\r\n.*}] \
     "load core file for environment test"
 
 gdb_assert { [check_for_env_var $env_var_name $env_var_value] } \
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 9ade9a16818..2cfdbdda09d 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -10312,8 +10312,18 @@ proc core_find {binfile {deletefiles {}} {arg ""} {output_file "/dev/null"}} {
 	}
     }
 
-    # tclint-disable command-args
-    catch "system \"(cd ${coredir}; ulimit -c unlimited; $coredump_filter_cmd; ${binfile} ${arg}; true) >${output_file} 2>&1\""
+    set cmd [subst_vars {
+	(cd ${coredir};
+	 ulimit -c unlimited;
+	 $coredump_filter_cmd;
+	 ${binfile} ${arg};
+	 true) \
+	    >${output_file} 2>&1}]
+    verbose -log "Executing on build: $cmd"
+    catch {
+	system $cmd
+    }
+
     #      remote_exec host "${binfile}"
     set binfile_basename [file tail $binfile]
     foreach i [list \
@@ -10343,8 +10353,16 @@ proc core_find {binfile {deletefiles {}} {arg ""} {output_file "/dev/null"}} {
 	# ulimit here if we didn't find a core file above.
 	# Oh, I should mention that any "braindamaged" non-Unix system has
 	# the same problem. I like the cd bit too, it's really neat'n stuff.
-	# tclint-disable command-args
-	catch "system \"(cd ${objdir}/${subdir}; ${binfile}; true) >/dev/null 2>&1\""
+	set cmd [subst_vars {
+	    (cd ${objdir}/${subdir};
+	     ${binfile};
+	     true) \
+		>/dev/null 2>&1}]
+	verbose -log "Executing on build: $cmd"
+	catch {
+	    system $cmd
+	}
+
 	foreach i "${objdir}/${subdir}/core ${objdir}/${subdir}/core.coremaker.c ${binfile}.core" {
 	    if {[remote_file build exists $i]} {
 		remote_exec build "mv $i $destcore"
-- 
2.51.0