X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Fpython%2Fpy-lazy-string.c;h=336cecb7361f2603f1190a826a93148201bff992;hb=2c473def12b08100e6b56261f01112db7f6aeab5;hp=68350679b81b008ca0ea93323cf7cfac8831f760;hpb=28e7fd62340426746f9c896cbc40c5d374ec47aa;p=deliverable%2Fbinutils-gdb.git

diff --git a/gdb/python/py-lazy-string.c b/gdb/python/py-lazy-string.c
index 68350679b8..336cecb736 100644
--- a/gdb/python/py-lazy-string.c
+++ b/gdb/python/py-lazy-string.c
@@ -1,6 +1,6 @@
 /* Python interface to lazy strings.
 
-   Copyright (C) 2010-2013 Free Software Foundation, Inc.
+   Copyright (C) 2010-2021 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -21,13 +21,12 @@
 #include "python-internal.h"
 #include "charset.h"
 #include "value.h"
-#include "exceptions.h"
 #include "valprint.h"
 #include "language.h"
-#include "gdb_assert.h"
 
-typedef struct {
+struct lazy_string_object {
   PyObject_HEAD
+
   /*  Holds the address of the lazy string.  */
   CORE_ADDR address;
 
@@ -37,24 +36,32 @@ 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;
-} lazy_string_object;
+  /* 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;
+};
 
-static PyTypeObject lazy_string_object_type;
+extern PyTypeObject lazy_string_object_type
+    CPYCHECKER_TYPE_OBJECT_FOR_TYPEDEF ("lazy_string_object");
 
 static PyObject *
 stpy_get_address (PyObject *self, void *closure)
 {
   lazy_string_object *self_string = (lazy_string_object *) self;
 
-  return gdb_py_long_from_ulongest (self_string->address);
+  return gdb_py_object_from_ulongest (self_string->address).release ();
 }
 
 static PyObject *
@@ -81,7 +88,7 @@ stpy_get_length (PyObject *self, void *closure)
 {
   lazy_string_object *self_string = (lazy_string_object *) self;
 
-  return PyLong_FromLong (self_string->length);
+  return gdb_py_object_from_longest (self_string->length).release ();
 }
 
 static PyObject *
@@ -89,28 +96,56 @@ 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;
-  volatile struct gdb_exception except;
 
   if (self_string->address == 0)
     {
-      PyErr_SetString (PyExc_MemoryError,
+      PyErr_SetString (gdbpy_gdb_memory_error,
 		       _("Cannot create a value from NULL."));
       return NULL;
     }
 
-  TRY_CATCH (except, RETURN_MASK_ALL)
+  try
+    {
+      struct type *type = type_object_to_type (self_string->type);
+      struct type *realtype;
+
+      gdb_assert (type != NULL);
+      realtype = check_typedef (type);
+      switch (realtype->code ())
+	{
+	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 (const gdb_exception &except)
     {
-      val = value_at_lazy (self_string->type, self_string->address);
+      GDB_PY_HANDLE_EXCEPTION (except);
     }
-  GDB_PY_HANDLE_EXCEPTION (except);
 
   return value_to_value_object (val);
 }
@@ -121,17 +156,31 @@ stpy_dealloc (PyObject *self)
   lazy_string_object *self_string = (lazy_string_object *) self;
 
   xfree (self_string->encoding);
+  Py_TYPE (self)->tp_free (self);
 }
 
+/* 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)
     {
-      PyErr_SetString (PyExc_MemoryError,
+      PyErr_SetString (gdbpy_gdb_memory_error,
 		       _("Cannot create a lazy string with address 0x0, " \
 			 "and a non-zero length."));
       return NULL;
@@ -144,6 +193,27 @@ gdbpy_create_lazy_string_object (CORE_ADDR address, long length,
       return NULL;
     }
 
+  realtype = check_typedef (type);
+  switch (realtype->code ())
+    {
+    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;
@@ -154,18 +224,19 @@ 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;
 }
 
-void
+int
 gdbpy_initialize_lazy_string (void)
 {
   if (PyType_Ready (&lazy_string_object_type) < 0)
-    return;
+    return -1;
 
   Py_INCREF (&lazy_string_object_type);
+  return 0;
 }
 
 /* Determine whether the printer object pointed to by OBJ is a
@@ -176,15 +247,37 @@ 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 (realtype->code ())
+    {
+    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 will either be set to NULL, or will be allocated with
-   xmalloc, in which case the callers is responsible for freeing
-   it.  */
+   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,
-			   long *length, char **encoding)
+			   struct type **str_elt_type,
+			   long *length,
+			   gdb::unique_xmalloc_ptr<char> *encoding)
 {
   lazy_string_object *lazy;
 
@@ -193,9 +286,9 @@ 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 = lazy->encoding ? xstrdup (lazy->encoding) : NULL;
+  encoding->reset (lazy->encoding ? xstrdup (lazy->encoding) : NULL);
 }
 
 
@@ -207,7 +300,7 @@ static PyMethodDef lazy_string_object_methods[] = {
 };
 
 
-static PyGetSetDef lazy_string_object_getset[] = {
+static gdb_PyGetSetDef lazy_string_object_getset[] = {
   { "address", stpy_get_address, NULL, "Address of the string.", NULL },
   { "encoding", stpy_get_encoding, NULL, "Encoding of the string.", NULL },
   { "length", stpy_get_length, NULL, "Length of the string.", NULL },
@@ -215,7 +308,7 @@ static PyGetSetDef lazy_string_object_getset[] = {
   { NULL }  /* Sentinel */
 };
 
-static PyTypeObject lazy_string_object_type = {
+PyTypeObject lazy_string_object_type = {
   PyVarObject_HEAD_INIT (NULL, 0)
   "gdb.LazyString",	          /*tp_name*/
   sizeof (lazy_string_object),	  /*tp_basicsize*/