This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
-var-info-path-expression
- From: Vladimir Prus <ghost at cs dot msu dot su>
- To: gdb-patches at sources dot redhat dot com
- Date: Mon, 25 Dec 2006 12:00:42 +0300
- Subject: -var-info-path-expression
This patch implements new MI command, -var-info-path-expression,
that, given a variable object, returns full expression that corresponds
to it. Both KDevelop and Eclipse have now code that guesses such
full expression, and that code is rather hacky, and not exactly correct.
Moreover, as soon as MI is taught to get the true type
polymorphic C++ objects and display fields of the real type, such full expression
cannot be computed in frontend at all.
The essence of this patch -- which expressions are returned in which cases -- are
ported without change from the Apple branch. The code structure is much
different though -- this patch capitalizes on MI refactoring patches I've posted
recently.
This is lightly tested by hand, I'll write automated tests later. There's no docs
either -- again, will be written after discussion.
There is a couple of issues with this patch:
- I don't much like 'var-info-path-expression' name, but
naming of MI commands is not very important.
- I'm not sure why we can't report full expression in the
output of -var-list-children. The code I have does not seem
very computationally expensive.
Comments are appreciated.
- Volodya
Implement -var-info-path-expression.
* mi/mi-cmds.h (mi_cmd_var_info_path_expression):
Declare.
* mi/mi-cmds.c (mi_cmds): Register var-info-path-expression.
* mi/mi-cmd-var.c (mi_cmd_var_info_path_expression): New.
* varobj.c (struct varobj): New field 'path_expr'.
(c_path_expr_of_child, cplus_path_expr_of_child)
(java_path_expr_of_child): New.
(struct language_specific): New field path_expr_of_child.
(varobj_create): Initialize the path_expr field.
(varobj_get_path_expr): New.
(new_variable): Initialize the path_expr field.
(free_variable): Free the path_expr field.
(adjust_value_for_children_access): New parameter
WAS_TYPE.
(c_number_of_children): Adjust.
(c_describe_child): New parameter CFULL_EXPRESSION.
Compute full expression.
(c_value_of_child, c_type_of_child): Adjust.
(cplus_number_of_children): Adjust.
(cplus_describe_child): New parameter CFULL_EXPRESSION.
Compute full expression.
(cplus_name_of_child, cplus_value_of_child)
(cplus_type_of_child): Adjust.
* varobj.h (varobj_get_path_expr): Declare.
--- gdb/mi/mi-cmds.h (/patches/gdb/path_4_unify_cpp/gdb_mainline) (revision 2940)
+++ gdb/mi/mi-cmds.h (/patches/gdb/path_expression/gdb_mainline) (revision 2940)
@@ -108,6 +108,7 @@ extern mi_cmd_argv_ftype mi_cmd_var_crea
extern mi_cmd_argv_ftype mi_cmd_var_delete;
extern mi_cmd_argv_ftype mi_cmd_var_evaluate_expression;
extern mi_cmd_argv_ftype mi_cmd_var_info_expression;
+extern mi_cmd_argv_ftype mi_cmd_var_info_path_expression;
extern mi_cmd_argv_ftype mi_cmd_var_info_num_children;
extern mi_cmd_argv_ftype mi_cmd_var_info_type;
extern mi_cmd_argv_ftype mi_cmd_var_list_children;
--- gdb/mi/mi-cmds.c (/patches/gdb/path_4_unify_cpp/gdb_mainline) (revision 2940)
+++ gdb/mi/mi-cmds.c (/patches/gdb/path_expression/gdb_mainline) (revision 2940)
@@ -155,6 +155,8 @@ struct mi_cmd mi_cmds[] =
{ "var-create", { NULL, 0 }, 0, mi_cmd_var_create},
{ "var-delete", { NULL, 0 }, 0, mi_cmd_var_delete},
{ "var-evaluate-expression", { NULL, 0 }, 0, mi_cmd_var_evaluate_expression},
+ { "var-info-path-expression", { NULL, 0 }, 0,
+ mi_cmd_var_info_path_expression},
{ "var-info-expression", { NULL, 0 }, 0, mi_cmd_var_info_expression},
{ "var-info-num-children", { NULL, 0 }, 0, mi_cmd_var_info_num_children},
{ "var-info-type", { NULL, 0 }, 0, mi_cmd_var_info_type},
--- gdb/mi/mi-cmd-var.c (/patches/gdb/path_4_unify_cpp/gdb_mainline) (revision 2940)
+++ gdb/mi/mi-cmd-var.c (/patches/gdb/path_expression/gdb_mainline) (revision 2940)
@@ -380,6 +380,27 @@ mi_cmd_var_info_type (char *command, cha
}
enum mi_cmd_result
+mi_cmd_var_info_path_expression (char *command, char **argv, int argc)
+{
+ struct varobj *var;
+ char *path_expr;
+
+ if (argc != 1)
+ error ("mi_cmd_var_info_path_expression: Usage: NAME.");
+
+ /* Get varobj handle, if a valid var obj name was specified */
+ var = varobj_get_handle (argv[0]);
+ if (var == NULL)
+ error ("mi_cmd_var_info_path_expression: Variable object not found");
+
+ path_expr = varobj_get_path_expr (var);
+
+ ui_out_field_string (uiout, "path_expr", path_expr);
+
+ return MI_CMD_DONE;
+}
+
+enum mi_cmd_result
mi_cmd_var_info_expression (char *command, char **argv, int argc)
{
enum varobj_languages lang;
--- gdb/varobj.c (/patches/gdb/path_4_unify_cpp/gdb_mainline) (revision 2940)
+++ gdb/varobj.c (/patches/gdb/path_expression/gdb_mainline) (revision 2940)
@@ -97,6 +97,10 @@ struct varobj
/* NOTE: This is the "expression" */
char *name;
+ /* Alloc'd expression for this child. Can be used to create a
+ root variable corresponding to this child. */
+ char *path_expr;
+
/* The alloc'd name for this variable's object. This is here for
convenience when constructing this object's children. */
char *obj_name;
@@ -216,6 +220,8 @@ static char *c_name_of_variable (struct
static char *c_name_of_child (struct varobj *parent, int index);
+static char *c_path_expr_of_child (struct varobj *child);
+
static struct value *c_value_of_root (struct varobj **var_handle);
static struct value *c_value_of_child (struct varobj *parent, int index);
@@ -236,6 +242,8 @@ static char *cplus_name_of_variable (str
static char *cplus_name_of_child (struct varobj *parent, int index);
+static char *cplus_path_expr_of_child (struct varobj *child);
+
static struct value *cplus_value_of_root (struct varobj **var_handle);
static struct value *cplus_value_of_child (struct varobj *parent, int index);
@@ -254,6 +262,8 @@ static char *java_name_of_variable (stru
static char *java_name_of_child (struct varobj *parent, int index);
+static char *java_path_expr_of_child (struct varobj *child);
+
static struct value *java_value_of_root (struct varobj **var_handle);
static struct value *java_value_of_child (struct varobj *parent, int index);
@@ -281,6 +291,10 @@ struct language_specific
/* The name of the INDEX'th child of PARENT. */
char *(*name_of_child) (struct varobj * parent, int index);
+ /* Returns the rooted expression of CHILD, which is a variable
+ obtain that has some parent. */
+ char *(*path_expr_of_child) (struct varobj * child);
+
/* The ``struct value *'' of the root variable ROOT. */
struct value *(*value_of_root) (struct varobj ** root_handle);
@@ -306,6 +320,7 @@ static struct language_specific
c_number_of_children,
c_name_of_variable,
c_name_of_child,
+ c_path_expr_of_child,
c_value_of_root,
c_value_of_child,
c_type_of_child,
@@ -318,6 +333,7 @@ static struct language_specific
c_number_of_children,
c_name_of_variable,
c_name_of_child,
+ c_path_expr_of_child,
c_value_of_root,
c_value_of_child,
c_type_of_child,
@@ -330,6 +346,7 @@ static struct language_specific
cplus_number_of_children,
cplus_name_of_variable,
cplus_name_of_child,
+ cplus_path_expr_of_child,
cplus_value_of_root,
cplus_value_of_child,
cplus_type_of_child,
@@ -342,6 +359,7 @@ static struct language_specific
java_number_of_children,
java_name_of_variable,
java_name_of_child,
+ java_path_expr_of_child,
java_value_of_root,
java_value_of_child,
java_type_of_child,
@@ -425,6 +443,7 @@ varobj_create (char *objname,
char *p;
enum varobj_languages lang;
struct value *value;
+ int expr_len;
/* Parse and evaluate the expression, filling in as much
of the variable's data as possible */
@@ -469,7 +488,10 @@ varobj_create (char *objname,
var->format = variable_default_display (var);
var->root->valid_block = innermost_block;
- var->name = savestring (expression, strlen (expression));
+ expr_len = strlen (expression);
+ var->name = savestring (expression, expr_len);
+ /* For a root var, the name and the expr are the same. */
+ var->path_expr = savestring (expression, expr_len);
/* When the frame is different from the current frame,
we must select the appropriate frame before parsing
@@ -757,6 +779,21 @@ varobj_get_gdb_type (struct varobj *var)
return var->type;
}
+/* Return a pointer to the full rooted expression of varobj VAR.
+ If it has not been computed yet, compute it */
+char *
+varobj_get_path_expr (struct varobj *var)
+{
+ if (var->path_expr != NULL)
+ return var->path_expr;
+ else if (is_root_p (var))
+ return var->name;
+ else
+ {
+ return (*var->root->lang->path_expr_of_child) (var);
+ }
+}
+
enum varobj_languages
varobj_get_language (struct varobj *var)
{
@@ -1357,6 +1394,7 @@ new_variable (void)
var = (struct varobj *) xmalloc (sizeof (struct varobj));
var->name = NULL;
+ var->path_expr = NULL;
var->obj_name = NULL;
var->index = -1;
var->type = NULL;
@@ -1401,6 +1439,7 @@ free_variable (struct varobj *var)
xfree (var->name);
xfree (var->obj_name);
+ xfree (var->path_expr);
xfree (var);
}
@@ -1683,13 +1722,21 @@ varobj_value_is_changeable_p (struct var
Both TYPE and *TYPE should be non-null. VALUE
can be null if we want to only translate type.
*VALUE can be null as well -- if the parent
- value is not known. */
+ value is not known.
+
+ If WAS_PTR is not NULL, set *WAS_PTR to 0 or 1
+ depending on whether pointer was deferenced
+ in this function. */
static void
adjust_value_for_children_access (struct value **value,
- struct type **type)
+ struct type **type,
+ int *was_ptr)
{
gdb_assert (type && *type);
+ if (was_ptr)
+ *was_ptr = 0;
+
*type = check_typedef (*type);
/* If the parent is reference, we always strip the
@@ -1721,6 +1768,8 @@ adjust_value_for_children_access (struct
if (value && *value)
gdb_value_ind (*value, value);
*type = target_type;
+ if (was_ptr)
+ *was_ptr = 1;
}
}
}
@@ -1733,7 +1782,7 @@ c_number_of_children (struct varobj *var
int children = 0;
struct type *target;
- adjust_value_for_children_access (NULL, &type);
+ adjust_value_for_children_access (NULL, &type, NULL);
target = get_target_type (type);
switch (TYPE_CODE (type))
@@ -1826,10 +1875,13 @@ value_struct_element_index (struct value
to NULL. */
static void
c_describe_child (struct varobj *parent, int index,
- char **cname, struct value **cvalue, struct type **ctype)
+ char **cname, struct value **cvalue, struct type **ctype,
+ char **cfull_expression)
{
struct value *value = parent->value;
struct type *type = get_type (parent);
+ char *parent_expression = NULL;
+ int was_ptr;
if (cname)
*cname = NULL;
@@ -1837,8 +1889,13 @@ c_describe_child (struct varobj *parent,
*cvalue = NULL;
if (ctype)
*ctype = NULL;
+ if (cfull_expression)
+ {
+ *cfull_expression = NULL;
+ parent_expression = varobj_get_path_expr (parent);
+ }
- adjust_value_for_children_access (&value, &type);
+ adjust_value_for_children_access (&value, &type, &was_ptr);
switch (TYPE_CODE (type))
{
@@ -1858,6 +1915,12 @@ c_describe_child (struct varobj *parent,
if (ctype)
*ctype = get_target_type (type);
+ if (cfull_expression)
+ *cfull_expression = xstrprintf ("(%s)[%d]", parent_expression,
+ index
+ + TYPE_LOW_BOUND (TYPE_INDEX_TYPE (type)));
+
+
break;
case TYPE_CODE_STRUCT:
@@ -1877,6 +1940,13 @@ c_describe_child (struct varobj *parent,
if (ctype)
*ctype = TYPE_FIELD_TYPE (type, index);
+ if (cfull_expression)
+ {
+ char *join = was_ptr ? "->" : ".";
+ *cfull_expression = xstrprintf ("(%s)%s%s", parent_expression, join,
+ TYPE_FIELD_NAME (type, index));
+ }
+
break;
case TYPE_CODE_PTR:
@@ -1892,6 +1962,9 @@ c_describe_child (struct varobj *parent,
right. */
if (ctype)
*ctype = get_target_type (type);
+
+ if (cfull_expression)
+ *cfull_expression = xstrprintf ("*(%s)", parent_expression);
break;
@@ -1899,6 +1972,8 @@ c_describe_child (struct varobj *parent,
/* This should not happen */
if (cname)
*cname = xstrdup ("???");
+ if (cfull_expression)
+ *cfull_expression = xstrdup ("???");
/* Don't set value and type, we don't know then. */
}
}
@@ -1907,10 +1982,18 @@ static char *
c_name_of_child (struct varobj *parent, int index)
{
char *name;
- c_describe_child (parent, index, &name, NULL, NULL);
+ c_describe_child (parent, index, &name, NULL, NULL, NULL);
return name;
}
+static char *
+c_path_expr_of_child (struct varobj *child)
+{
+ c_describe_child (child->parent, child->index, NULL, NULL, NULL,
+ &child->path_expr);
+ return child->path_expr;
+}
+
static struct value *
c_value_of_root (struct varobj **var_handle)
{
@@ -1961,7 +2044,7 @@ static struct value *
c_value_of_child (struct varobj *parent, int index)
{
struct value *value = NULL;
- c_describe_child (parent, index, NULL, &value, NULL);
+ c_describe_child (parent, index, NULL, &value, NULL, NULL);
if (value != NULL)
release_value (value);
@@ -1972,7 +2055,7 @@ static struct type *
c_type_of_child (struct varobj *parent, int index)
{
struct type *type = NULL;
- c_describe_child (parent, index, NULL, NULL, &type);
+ c_describe_child (parent, index, NULL, NULL, &type, NULL);
return type;
}
@@ -2066,7 +2149,7 @@ cplus_number_of_children (struct varobj
if (!CPLUS_FAKE_CHILD (var))
{
type = var->type;
- adjust_value_for_children_access (NULL, &type);
+ adjust_value_for_children_access (NULL, &type, NULL);
if (((TYPE_CODE (type)) == TYPE_CODE_STRUCT) ||
((TYPE_CODE (type)) == TYPE_CODE_UNION))
@@ -2093,7 +2176,7 @@ cplus_number_of_children (struct varobj
int kids[3];
type = var->parent->type;
- adjust_value_for_children_access (NULL, &type);
+ adjust_value_for_children_access (NULL, &type, NULL);
cplus_class_num_children (type, kids);
if (strcmp (var->name, "public") == 0)
@@ -2164,11 +2247,14 @@ match_accessibility (struct type *type,
static void
cplus_describe_child (struct varobj *parent, int index,
- char **cname, struct value **cvalue, struct type **ctype)
+ char **cname, struct value **cvalue, struct type **ctype,
+ char **cfull_expression)
{
char *name = 0;
struct value *value;
struct type *type;
+ int was_ptr;
+ char *parent_expression = NULL;
if (cname)
*cname = NULL;
@@ -2176,24 +2262,30 @@ cplus_describe_child (struct varobj *par
*cvalue = NULL;
if (ctype)
*ctype = NULL;
-
+ if (cfull_expression)
+ *cfull_expression = NULL;
if (CPLUS_FAKE_CHILD (parent))
{
value = parent->parent->value;
type = get_type (parent->parent);
+ if (cfull_expression)
+ parent_expression = varobj_get_path_expr (parent->parent);
}
else
{
value = parent->value;
type = get_type (parent);
+ if (cfull_expression)
+ parent_expression = varobj_get_path_expr (parent);
}
- adjust_value_for_children_access (&value, &type);
+ adjust_value_for_children_access (&value, &type, &was_ptr);
if (TYPE_CODE (type) == TYPE_CODE_STRUCT
|| TYPE_CODE (type) == TYPE_CODE_STRUCT)
{
+ char *join = was_ptr ? "->" : ".";
if (CPLUS_FAKE_CHILD (parent))
{
/* The fields of the class type are ordered as they
@@ -2228,6 +2320,11 @@ cplus_describe_child (struct varobj *par
if (ctype)
*ctype = TYPE_FIELD_TYPE (type, type_index);
+
+ if (cfull_expression)
+ *cfull_expression = xstrprintf ("((%s)%s%s)", parent_expression,
+ join,
+ TYPE_FIELD_NAME (type, type_index));
}
else if (index < TYPE_N_BASECLASSES (type))
{
@@ -2245,6 +2342,15 @@ cplus_describe_child (struct varobj *par
{
*ctype = TYPE_FIELD_TYPE (type, index);
}
+
+ if (cfull_expression)
+ {
+ char *ptr = was_ptr ? " *" : "";
+ *cfull_expression = xstrprintf ("((%s%s) %s)",
+ TYPE_FIELD_NAME (type, index),
+ ptr,
+ parent_expression);
+ }
}
else
{
@@ -2291,12 +2397,12 @@ cplus_describe_child (struct varobj *par
if (cname)
*cname = access;
- /* Value and type are null here. */
+ /* Value and type and full expression are null here. */
}
}
else
{
- c_describe_child (parent, index, cname, cvalue, ctype);
+ c_describe_child (parent, index, cname, cvalue, ctype, cfull_expression);
}
}
@@ -2304,10 +2410,18 @@ static char *
cplus_name_of_child (struct varobj *parent, int index)
{
char *name = NULL;
- cplus_describe_child (parent, index, &name, NULL, NULL);
+ cplus_describe_child (parent, index, &name, NULL, NULL, NULL);
return name;
}
+static char *
+cplus_path_expr_of_child (struct varobj *child)
+{
+ cplus_describe_child (child->parent, child->index, NULL, NULL, NULL,
+ &child->path_expr);
+ return child->path_expr;
+}
+
static struct value *
cplus_value_of_root (struct varobj **var_handle)
{
@@ -2318,7 +2432,7 @@ static struct value *
cplus_value_of_child (struct varobj *parent, int index)
{
struct value *value = NULL;
- cplus_describe_child (parent, index, NULL, &value, NULL);
+ cplus_describe_child (parent, index, NULL, &value, NULL, NULL);
return value;
}
@@ -2326,7 +2440,7 @@ static struct type *
cplus_type_of_child (struct varobj *parent, int index)
{
struct type *type = NULL;
- cplus_describe_child (parent, index, NULL, NULL, &type);
+ cplus_describe_child (parent, index, NULL, NULL, &type, NULL);
return type;
}
@@ -2398,6 +2512,12 @@ java_name_of_child (struct varobj *paren
return name;
}
+static char *
+java_path_expr_of_child (struct varobj *child)
+{
+ return NULL;
+}
+
static struct value *
java_value_of_root (struct varobj **var_handle)
{
--- gdb/varobj.h (/patches/gdb/path_4_unify_cpp/gdb_mainline) (revision 2940)
+++ gdb/varobj.h (/patches/gdb/path_expression/gdb_mainline) (revision 2940)
@@ -87,6 +87,8 @@ extern char *varobj_get_type (struct var
extern struct type *varobj_get_gdb_type (struct varobj *var);
+extern char *varobj_get_path_expr (struct varobj *var);
+
extern enum varobj_languages varobj_get_language (struct varobj *var);
extern int varobj_get_attributes (struct varobj *var);
Property changes on:
___________________________________________________________________
Name: csl:base
-/all/patches/gdb/path_3_unify/gdb_mainline
+/all/patches/gdb/path_4_unify_cpp/gdb_mainline
Name: svk:merge
d48a11ec-ee1c-0410-b3f5-c20844f99675:/patches/gdb/path_1/gdb_mainline:2869
+d48a11ec-ee1c-0410-b3f5-c20844f99675:/patches/gdb/path_2_children/gdb_mainline:2879
d48a11ec-ee1c-0410-b3f5-c20844f99675:/patches/gdb/path_3_unify/gdb_mainline:2930
-d48a11ec-ee1c-0410-b3f5-c20844f99675:/patches/gdb/path_expression/gdb_mainline:2562
+d48a11ec-ee1c-0410-b3f5-c20844f99675:/patches/gdb/path_4_unify_cpp/gdb_mainline:2937
e7755896-6108-0410-9592-8049d3e74e28:/mirrors/gdb/trunk:157978