gdb: Allow quoting around string options in the gdb::option framework

Currently string options must be a single string with no whitespace,
this limitation prevents the gdb::option framework being used in some
places.

After this commit, string options can be quoted in single or double
quotes, and quote characters can be escaped with a backslash if needed
to either place them within quotes, or to avoid starting a quoted
argument.

This test adds a new function extract_string_maybe_quoted which is
basically a copy of extract_arg_maybe_quoted from cli/cli-utils.c,
however, the cli-utils.c function will be deleted in the next commit.

There are tests to exercise the new quoting mechanism.

gdb/ChangeLog:

	* cli/cli-option.c (parse_option): Use extract_string_maybe_quoted
	to extract string arguments.
	* common/common-utils.c (extract_string_maybe_quoted): New function.
	* common/common-utils.h (extract_string_maybe_quoted): Declare.

gdb/testsuite/ChangeLog:

	* gdb.base/options.exp (expect_string): Dequote strings in
	results.
	(test-string): Test strings with different quoting and reindent.

1 files changed, 39 insertions, 17 deletions

diff --git a/gdb/testsuite/gdb.base/options.exp b/gdb/testsuite/gdb.base/options.exp
index e8f571d..561ca1d 100644
--- a/gdb/testsuite/gdb.base/options.exp
+++ b/gdb/testsuite/gdb.base/options.exp
@@ -128,6 +128,13 @@ proc expect_integer {option val operand} {
 # test-options xxx", with -string set to $STR.  OPERAND is the
 # expected operand.
 proc expect_string {str operand} {
+    # Dequote the string in the expected output.
+    if { ( [string range $str 0 0] == "\""
+	   && [string range $str end end] == "\"")
+	 || ([string range $str 0 0] == "'"
+	     && [string range $str end end] == "'")} {
+	set str [string range $str 1 end-1]
+    }
     return "-flag 0 -xx1 0 -xx2 0 -bool 0 -enum xxx -uint 0 -zuint-unl 0 -string '$str' -- $operand"
 }
 
@@ -967,26 +974,41 @@ proc_with_prefix test-string {variant} {
 	    "-string requires an argument"
     }
 
-    res_test_gdb_complete_none \
-	"1 [expect_none ""]" \
-	"$cmd -string STR"
-    gdb_test "$cmd -string STR --" [expect_string "STR" ""]
+    foreach_with_prefix str {
+	"STR"
+	"\"STR\""
+	"\\\"STR"
+	"'STR'"
+	"\\'STR"
+	"\"STR AAA\""
+	"'STR BBB'"
+	"\"STR 'CCC' DDD\""
+	"'STR \"EEE\" FFF'"
+	"\"STR \\\"GGG\\\" HHH\""
+	"'STR \\\'III\\\' JJJ'"
+    } {
+	res_test_gdb_complete_none \
+	    "1 [expect_none ""]" \
+	    "$cmd -string ${str}"
+	gdb_test "$cmd -string ${str} --" [expect_string "${str}" ""]
 
-    # Completing at "-" after parsing STR should list all options.
-    res_test_gdb_complete_multiple \
-	"1 [expect_string "STR" "-"]" \
-	"$cmd -string STR " "-" "" $all_options
+	# Completing at "-" after parsing STR should list all options.
+	res_test_gdb_complete_multiple \
+	    "1 [expect_string "${str}" "-"]" \
+	    "$cmd -string ${str} " "-" "" $all_options
 
-    # Check that only FOO is considered part of the string's value.
-    # I.e., that we stop parsing the string at the first whitespace.
-    if {$variant == "require-delimiter"} {
-	res_test_gdb_complete_none \
-	    "1 [expect_string "FOO" "BAR"]" \
-	    "$cmd -string FOO BAR"
-    } else {
-	res_test_gdb_complete_none "0 BAR" "$cmd -string FOO BAR"
+	# Check that only $STR is considered part of the string's value.
+	# I.e., that we stop parsing the string at the first
+	# whitespace or after the closing quote of $STR.
+	if {$variant == "require-delimiter"} {
+	    res_test_gdb_complete_none \
+		"1 [expect_string "${str}" "BAR"]" \
+		"$cmd -string ${str} BAR"
+	} else {
+	    res_test_gdb_complete_none "0 BAR" "$cmd -string ${str} BAR"
+	}
+	gdb_test "$cmd -string ${str} BAR --" "Unrecognized option at: BAR --"
     }
-    gdb_test "$cmd -string FOO BAR --" "Unrecognized option at: BAR --"
 }
 
 # Run the options framework tests first.