Doug Evans writes:
> On Sun, Nov 6, 2016 at 5:14 PM, Doug Evans <dje@google.com> wrote:
> > Hi. This is the python side of the patch set.
> >
> > 2016-11-06 Doug Evans <dje@google.com>
> >
> > 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.
>
> Rebased, re-regression tested on amd64-linux, and committed.
> [I'll post the committed patch as soon as I can get sendmail on my box
> working again, bleah. We still don't allow attachments do we?]
Had to rework some local changes due to emacs version differences.
commit 34b433203b5f56149c27a8dfea21a921392cb158
Author: Doug Evans <dje@google.com>
Date: Wed Mar 15 15:35:13 2017 -0700
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.
- gdb_test "python print (snstr.address)" "0" "test lazy string address"
-}
-
-
proc test_inferior_function_call {} {
global gdb_prompt hex decimal
@@ -534,7 +511,6 @@ if ![runto_main] then {
test_value_in_inferior
test_inferior_function_call
-test_lazy_strings
test_value_after_death
# Test either C or C++ values.
@@ -1,5 +1,20 @@
2017-03-16 Doug Evans <dje@google.com>
+ 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.
+
+2017-03-16 Doug Evans <dje@google.com>
+
* guile/guile-internal.h (tyscm_scm_to_type): Declare.
* guile/scm-type.c (tyscm_scm_to_type): New function.
@@ -26,6 +26,7 @@
typedef struct {
PyObject_HEAD
+
/* Holds the address of the lazy string. */
CORE_ADDR address;
@@ -35,14 +36,21 @@ typedef struct {
encoding when the sting is printed. */
char *encoding;
- /* Holds the length of the string in characters. If the
- length is -1, then the string will be fetched and encoded up to
- the first null of appropriate width. */
+ /* If TYPE is an array: If the length is known, then this value is the
+ array's length, otherwise it is -1.
+ If TYPE is not an array: Then this value represents the string's
length.
+ In either case, if the value is -1 then the string will be fetched and
+ encoded up to the first null of appropriate width. */
long length;
- /* This attribute holds the type that is represented by the lazy
- string's type. */
- struct type *type;
+ /* This attribute holds the type of the string.
+ For example if the lazy string was created from a C "char*" then TYPE
+ represents a C "char*".
+ To get the type of the character in the string call
+ stpy_lazy_string_elt_type.
+ This is recorded as a PyObject so that we take advantage of support
for
+ preserving the type should its owning objfile go away. */
+ PyObject *type;
} lazy_string_object;
extern PyTypeObject lazy_string_object_type
@@ -88,11 +96,12 @@ stpy_get_type (PyObject *self, void *closure)
{
lazy_string_object *str_obj = (lazy_string_object *) self;
- return type_to_type_object (str_obj->type);
+ Py_INCREF (str_obj->type);
+ return str_obj->type;
}
static PyObject *
-stpy_convert_to_value (PyObject *self, PyObject *args)
+stpy_convert_to_value (PyObject *self, PyObject *args)
{
lazy_string_object *self_string = (lazy_string_object *) self;
struct value *val = NULL;
@@ -106,7 +115,32 @@ stpy_convert_to_value (PyObject *self, PyObject *args)
TRY
{
- val = value_at_lazy (self_string->type, self_string->address);
+ struct type *type = type_object_to_type (self_string->type);
+ struct type *realtype;
+
+ gdb_assert (type != NULL);
+ realtype = check_typedef (type);
+ switch (TYPE_CODE (realtype))
+ {
+ case TYPE_CODE_PTR:
+ /* If a length is specified we need to convert this to an array
+ of the specified size. */
+ if (self_string->length != -1)
+ {
+ /* PR 20786: There's no way to specify an array of length zero.
+ Record a length of [0,-1] which is how Ada does it. Anything
+ we do is broken, but this is one possible solution. */
+ type = lookup_array_range_type (TYPE_TARGET_TYPE (realtype),
+ 0, self_string->length - 1);
+ val = value_at_lazy (type, self_string->address);
+ }
+ else
+ val = value_from_pointer (type, self_string->address);
+ break;
+ default:
+ val = value_at_lazy (type, self_string->address);
+ break;
+ }
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -125,11 +159,24 @@ stpy_dealloc (PyObject *self)
xfree (self_string->encoding);
}
+/* Low level routine to create a <gdb.LazyString> object.
+
+ Note: If TYPE is an array, LENGTH either must be -1 (meaning to use the
+ size of the array, which may itself be unknown in which case a length of
+ -1 is still used) or must be the length of the array. */
+
PyObject *
gdbpy_create_lazy_string_object (CORE_ADDR address, long length,
- const char *encoding, struct type *type)
+ const char *encoding, struct type *type)
{
lazy_string_object *str_obj = NULL;
+ struct type *realtype;
+
+ if (length < -1)
+ {
+ PyErr_SetString (PyExc_ValueError, _("Invalid length."));
+ return NULL;
+ }
if (address == 0 && length != 0)
{
@@ -146,6 +193,27 @@ gdbpy_create_lazy_string_object (CORE_ADDR address,
long length,
return NULL;
}
+ realtype = check_typedef (type);
+ switch (TYPE_CODE (realtype))
+ {
+ case TYPE_CODE_ARRAY:
+ {
+ LONGEST array_length = -1;
+ LONGEST low_bound, high_bound;
+
+ if (get_array_bounds (realtype, &low_bound, &high_bound))
+ array_length = high_bound - low_bound + 1;
+ if (length == -1)
+ length = array_length;
+ else if (length != array_length)
+ {
+ PyErr_SetString (PyExc_ValueError, _("Invalid length."));
+ return NULL;
+ }
+ break;
+ }
+ }
+
str_obj = PyObject_New (lazy_string_object, &lazy_string_object_type);
if (!str_obj)
return NULL;
@@ -156,7 +224,7 @@ gdbpy_create_lazy_string_object (CORE_ADDR address,
long length,
str_obj->encoding = NULL;
else
str_obj->encoding = xstrdup (encoding);
- str_obj->type = type;
+ str_obj->type = type_to_type_object (type);
return (PyObject *) str_obj;
}
@@ -179,12 +247,35 @@ gdbpy_is_lazy_string (PyObject *result)
return PyObject_TypeCheck (result, &lazy_string_object_type);
}
+/* Return the type of a character in lazy string LAZY. */
+
+static struct type *
+stpy_lazy_string_elt_type (lazy_string_object *lazy)
+{
+ struct type *type = type_object_to_type (lazy->type);
+ struct type *realtype;
+
+ gdb_assert (type != NULL);
+ realtype = check_typedef (type);
+
+ switch (TYPE_CODE (realtype))
+ {
+ case TYPE_CODE_PTR:
+ case TYPE_CODE_ARRAY:
+ return TYPE_TARGET_TYPE (realtype);
+ default:
+ /* This is done to preserve existing behaviour. PR 20769.
+ E.g., gdb.parse_and_eval("my_int_variable").lazy_string().type. */
+ return realtype;
+ }
+}
+
/* Extract the parameters from the lazy string object STRING.
ENCODING may be set to NULL, if no encoding is found. */
void
gdbpy_extract_lazy_string (PyObject *string, CORE_ADDR *addr,
- struct type **str_type,
+ struct type **str_elt_type,
long *length,
gdb::unique_xmalloc_ptr<char> *encoding)
{
@@ -195,7 +286,7 @@ gdbpy_extract_lazy_string (PyObject *string, CORE_ADDR
*addr,
lazy = (lazy_string_object *) string;
*addr = lazy->address;
- *str_type = lazy->type;
+ *str_elt_type = stpy_lazy_string_elt_type (lazy);
*length = lazy->length;
encoding->reset (lazy->encoding ? xstrdup (lazy->encoding) : NULL);
}
@@ -400,9 +400,19 @@ valpy_get_dynamic_type (PyObject *self, void *closure)
A lazy string is a pointer to a string with an optional encoding and
length. If ENCODING is not given, encoding is set to None. If an
ENCODING is provided the encoding parameter is set to ENCODING, but
- the string is not encoded. If LENGTH is provided then the length
- parameter is set to LENGTH, otherwise length will be set to -1 (first
- null of appropriate with). */
+ the string is not encoded.
+ If LENGTH is provided then the length parameter is set to LENGTH.
+ Otherwise if the value is an array of known length then the array's
length
+ is used. Otherwise the length will be set to -1 (meaning first null of
+ appropriate with).
+
+ Note: In order to not break any existing uses this allows creating
+ lazy strings from anything. PR 20769. E.g.,
+ gdb.parse_and_eval("my_int_variable").lazy_string().
+ "It's easier to relax restrictions than it is to impose them after the
+ fact." So we should be flagging any unintended uses as errors, but it's
+ perhaps too late for that. */
+
static PyObject *
valpy_lazy_string (PyObject *self, PyObject *args, PyObject *kw)
{
@@ -416,16 +426,66 @@ valpy_lazy_string (PyObject *self, PyObject *args,
PyObject *kw)
&user_encoding, &length))
return NULL;
+ if (length < -1)
+ {
+ PyErr_SetString (PyExc_ValueError, _("Invalid length."));
+ return NULL;
+ }
+
TRY
{
scoped_value_mark free_values;
+ struct type *type, *realtype;
+ CORE_ADDR addr;
- if (TYPE_CODE (value_type (value)) == TYPE_CODE_PTR)
- value = value_ind (value);
+ type = value_type (value);
+ realtype = check_typedef (type);
+
+ switch (TYPE_CODE (realtype))
+ {
+ case TYPE_CODE_ARRAY:
+ {
+ LONGEST array_length = -1;
+ LONGEST low_bound, high_bound;
+
+ /* PR 20786: There's no way to specify an array of length zero.
+ Record a length of [0,-1] which is how Ada does it. Anything
+ we do is broken, but this one possible solution. */
+ if (get_array_bounds (realtype, &low_bound, &high_bound))
+ array_length = high_bound - low_bound + 1;
+ if (length == -1)
+ length = array_length;
+ else if (array_length == -1)
+ {
+ type = lookup_array_range_type (TYPE_TARGET_TYPE (realtype),
+ 0, length - 1);
+ }
+ else if (length != array_length)
+ {
+ /* We need to create a new array type with the
+ specified length. */
+ if (length > array_length)
+ error (_("Length is larger than array size."));
+ type = lookup_array_range_type (TYPE_TARGET_TYPE (realtype),
+ low_bound,
+ low_bound + length - 1);
+ }
+ addr = value_address (value);
+ break;
+ }
+ case TYPE_CODE_PTR:
+ /* If a length is specified we defer creating an array of the
+ specified width until we need to. */
+ addr = value_as_address (value);
+ break;
+ default:
+ /* Should flag an error here. PR 20769. */
+ addr = value_address (value);
+ break;
+ }
- str_obj = gdbpy_create_lazy_string_object (value_address (value),
length,
- user_encoding,
- value_type (value));
+ str_obj = gdbpy_create_lazy_string_object (addr, length,
user_encoding,
+ type);
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -1,7 +1,19 @@
+<<<<<<< HEAD
2017-03-16 Thomas Preud'homme <thomas.preudhomme@arm.com>
* gdb.cp/m-static.exp: Fix expectation for prototype of
test5.single_constructor and single_constructor::single_constructor.
+=======
+2017-03-15 Doug Evans <dje@google.com>
+
+ 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.
+>>>>>>> Fix various python lazy string bugs.
2017-03-14 Anton Kolesov <anton.kolesov@synopsys.com>
b/gdb/testsuite/gdb.python/py-lazy-string.c
@@ -18,6 +18,9 @@
int
main ()
{
+ const char *ptr = "pointer";
+ const char array[] = "array";
+ pointer typedef_ptr = "typedef pointer";
const char *null = 0;
return 0; /* break here */
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"
+ }
+}
b/gdb/testsuite/gdb.python/py-value.c
@@ -90,13 +90,11 @@ main (int argc, char *argv[])
char nullst[17] = "divide\0et\0impera";
void (*fp1) (void) = &func1;
int (*fp2) (int, int) = &func2;
- const char *sptr = "pointer";
const char *embed = "embedded x\201\202\203\204";
int a[3] = {1,2,3};
int *p = a;
int i = 2;
int *ptr_i = &i;
- const char *sn = 0;
struct str *xstr;
/* Prevent gcc from optimizing argv[] out. */
b/gdb/testsuite/gdb.python/py-value.exp
@@ -317,29 +317,6 @@ proc test_value_in_inferior {} {
"read string beyond declared size"
}
-proc test_lazy_strings {} {
-
- global hex
-
- gdb_test "print sptr" "\"pointer\""
- gdb_py_test_silent_cmd "python sptr = gdb.history (0)" "Get value from
history" 1
-
- gdb_py_test_silent_cmd "python lstr = sptr.lazy_string()" "Aquire lazy
string" 1
- gdb_test "python print (lstr.type)" "const char \*." "test lazy-string
type name equality"
- gdb_test "python print (sptr.type)" "const char \*." "test string type
name equality"
-
- # Prevent symbol on address 0x0 being printed.
- gdb_test_no_output "set print symbol off"
- gdb_test "print sn" "0x0"
-
- gdb_py_test_silent_cmd "python snptr = gdb.history (0)" "Get value from
history" 1
- gdb_test "python snstr = snptr.lazy_string(length=5)" ".*Cannot create a
lazy string with address.*" "test lazy string"
- gdb_py_test_silent_cmd "python snstr =
snptr.lazy_string(length=0)" "Succesfully create a lazy string" 1
- gdb_test "python print (snstr.length)" "0" "test lazy string length"