Fix various python lazy string bugs.

gdb/ChangeLog:

	PR python/17728, python/18439, python/18779
	* python/py-lazy-string.c (lazy_string_object): Clarify use of LENGTH
	member.  Change type of TYPE member to PyObject *.  All uses updated.
	(stpy_convert_to_value): Fix handling of TYPE_CODE_PTR.
	(gdbpy_create_lazy_string_object): Flag bad length values.
	Handle TYPE_CODE_ARRAY with possibly different user-provided length.
	Handle typedefs in incoming type.
	(stpy_lazy_string_elt_type): New function.
	(gdbpy_extract_lazy_string): Call it.
	* python/py-value.c (valpy_lazy_string): Flag bad length values.
	Fix handling of TYPE_CODE_PTR.  Handle TYPE_CODE_ARRAY.  Handle
	typedefs in incoming type.

gdb/testsuite/ChangeLog:

	PR python/17728, python/18439, python/18779
	* gdb.python/py-value.c (main) Delete locals sptr, sn.
	* gdb.python/py-lazy-string.c (pointer): New typedef.
	(main): New locals ptr, array, typedef_ptr.
	* gdb.python/py-value.exp: Move lazy string tests to ...
	* gdb.python/py-lazy-string.exp: ... here.  Add more tests for pointer,
	array, typedef lazy strings.

1 files changed, 38 insertions, 4 deletions

diff --git a/gdb/testsuite/gdb.python/py-lazy-string.exp b/gdb/testsuite/gdb.python/py-lazy-string.exp
index e3054f6..ff95a2e 100644
--- a/gdb/testsuite/gdb.python/py-lazy-string.exp
+++ b/gdb/testsuite/gdb.python/py-lazy-string.exp
@@ -34,9 +34,43 @@ if ![runto_main ] {
 gdb_breakpoint [gdb_get_line_number "break here"]
 gdb_continue_to_breakpoint "break here"
 
-gdb_test_no_output "python null = gdb.parse_and_eval(\"null\")"
+gdb_py_test_silent_cmd "python null = gdb.parse_and_eval(\"null\")" "get null value" 1
 
-gdb_test "python print(null.lazy_string(length=0).value())" \
-    "gdb.MemoryError: Cannot create a value from NULL.*Error while executing Python code."
+gdb_py_test_silent_cmd "python nullstr = null.lazy_string(length=0)" "create a null lazy string" 1
+gdb_test "python print (nullstr.length)" "0" "null lazy string length"
+gdb_test "python print (nullstr.address)" "0" "null lazy string address"
+gdb_test "python print (nullstr.type)" "const char \\*" "null lazy string type"
+gdb_test "python print(nullstr.value())" \
+    "gdb.MemoryError: Cannot create a value from NULL.*Error while executing Python code." \
+    "create value from NULL"
 gdb_test "python print(null.lazy_string(length=3).value())" \
-    "gdb.MemoryError: Cannot create a lazy string with address 0x0, and a non-zero length.*Error while executing Python code."
+    "gdb.MemoryError: Cannot create a lazy string with address 0x0, and a non-zero length.*Error while executing Python code." \
+    "null lazy string with non-zero length"
+gdb_test "python print(null.lazy_string(length=-2))" \
+    "ValueError: Invalid length.*Error while executing Python code." \
+    "bad length"
+
+foreach var_spec { { "ptr" "pointer" "const char \\*" -1 } \
+		   { "array" "array" "const char \\[6\\]" 6 } \
+		   { "typedef_ptr" "typedef pointer" "pointer" -1 } } {
+    set var [lindex $var_spec 0]
+    set value [lindex $var_spec 1]
+    set type [lindex $var_spec 2]
+    set length [lindex $var_spec 3]
+    with_test_prefix $var {
+	gdb_test "print $var" "\"$value\""
+	gdb_py_test_silent_cmd "python $var = gdb.history (0)" "get value from history" 1
+	gdb_py_test_silent_cmd "python l$var = $var.lazy_string()" "acquire lazy string" 1
+	gdb_test "python print ($var.type)" "$type" "string type name equality"
+	gdb_test "python print (l$var.type)" "$type" "lazy-string type name equality"
+	gdb_test "python print (l$var.length)" "$length" "lazy string length"
+	gdb_test "python print (l$var.value())" "\"$value\"" "lazy string value"
+	gdb_py_test_silent_cmd "python l2$var = $var.lazy_string(length=2)" "acquire lazy string, length 2" 1
+	gdb_test "python print (l2$var.length)" "2" "lazy string length 2"
+	gdb_test "python print (l2$var.value())" "\"[string range $value 0 1]\"" "lazy string length 2 value"
+	# This test will have to wait until gdb can handle it. There's no way,
+	# currently, to internally specify an array of length zero in the C
+	# language support.  PR 20786
+	#gdb_test "python print ($var.lazy_string(length=0).value())" "\"\"" "empty lazy string value"
+    }
+}