static int convert_variable_type(Dwarf_Die *vr_die,
struct kprobe_trace_arg *targ)
{
Dwarf_Die type;
char buf[16];
int ret;
if (die_get_real_type(vr_die, &type) == NULL) {
pr_warning("Failed to get a type information of %s.\n",
dwarf_diename(vr_die));
return -ENOENT;
}
ret = die_get_byte_size(&type) * 8;
if (ret) {
/* Check the bitwidth */
if (ret > MAX_BASIC_TYPE_BITS) {
pr_info("%s exceeds max-bitwidth."
" Cut down to %d bits.\n",
dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
ret = MAX_BASIC_TYPE_BITS;
}
ret = snprintf(buf, 16, "%c%d",
die_is_signed_type(&type) ? 's' : 'u', ret);
if (ret < 0 || ret >= 16) {
if (ret >= 16)
ret = -E2BIG;
pr_warning("Failed to convert variable type: %s\n",
strerror(-ret));
return ret;
}
targ->type = strdup(buf);
if (targ->type == NULL)
return -ENOMEM;
}
return 0;
}
static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
struct perf_probe_arg_field *field,
struct probe_trace_arg_ref **ref_ptr,
Dwarf_Die *die_mem)
{
struct probe_trace_arg_ref *ref = *ref_ptr;
Dwarf_Die type;
Dwarf_Word offs;
int ret, tag;
pr_debug("converting %s in %s\n", field->name, varname);
if (die_get_real_type(vr_die, &type) == NULL) {
pr_warning("Failed to get the type of %s.\n", varname);
return -ENOENT;
}
pr_debug2("Var real type: (%x)\n", (unsigned)dwarf_dieoffset(&type));
tag = dwarf_tag(&type);
if (field->name[0] == '[' &&
(tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
if (field->next)
/* Save original type for next field */
memcpy(die_mem, &type, sizeof(*die_mem));
/* Get the type of this array */
if (die_get_real_type(&type, &type) == NULL) {
pr_warning("Failed to get the type of %s.\n", varname);
return -ENOENT;
}
pr_debug2("Array real type: (%x)\n",
(unsigned)dwarf_dieoffset(&type));
if (tag == DW_TAG_pointer_type) {
ref = zalloc(sizeof(struct probe_trace_arg_ref));
if (ref == NULL)
return -ENOMEM;
if (*ref_ptr)
(*ref_ptr)->next = ref;
else
*ref_ptr = ref;
}
ref->offset += die_get_byte_size(&type) * field->index;
if (!field->next)
/* Save vr_die for converting types */
memcpy(die_mem, vr_die, sizeof(*die_mem));
goto next;
} else if (tag == DW_TAG_pointer_type) {
/* Check the pointer and dereference */
if (!field->ref) {
pr_err("Semantic error: %s must be referred by '->'\n",
field->name);
return -EINVAL;
}
/* Get the type pointed by this pointer */
if (die_get_real_type(&type, &type) == NULL) {
pr_warning("Failed to get the type of %s.\n", varname);
return -ENOENT;
}
/* Verify it is a data structure */
if (dwarf_tag(&type) != DW_TAG_structure_type) {
pr_warning("%s is not a data structure.\n", varname);
return -EINVAL;
}
ref = zalloc(sizeof(struct probe_trace_arg_ref));
if (ref == NULL)
return -ENOMEM;
if (*ref_ptr)
(*ref_ptr)->next = ref;
else
*ref_ptr = ref;
} else {
/* Verify it is a data structure */
if (tag != DW_TAG_structure_type) {
pr_warning("%s is not a data structure.\n", varname);
return -EINVAL;
}
if (field->name[0] == '[') {
pr_err("Semantic error: %s is not a pointor"
" nor array.\n", varname);
return -EINVAL;
}
if (field->ref) {
pr_err("Semantic error: %s must be referred by '.'\n",
field->name);
return -EINVAL;
}
if (!ref) {
pr_warning("Structure on a register is not "
"supported yet.\n");
return -ENOTSUP;
}
}
if (die_find_member(&type, field->name, die_mem) == NULL) {
pr_warning("%s(tyep:%s) has no member %s.\n", varname,
dwarf_diename(&type), field->name);
return -EINVAL;
}
/* Get the offset of the field */
ret = die_get_data_member_location(die_mem, &offs);
if (ret < 0) {
pr_warning("Failed to get the offset of %s.\n", field->name);
return ret;
}
ref->offset += (long)offs;
next:
/* Converting next field */
if (field->next)
return convert_variable_fields(die_mem, field->name,
field->next, &ref, die_mem);
else
return 0;
}
static int convert_variable_type(Dwarf_Die *vr_die,
struct probe_trace_arg *tvar,
const char *cast)
{
struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
Dwarf_Die type;
char buf[16];
int ret;
/* TODO: check all types */
if (cast && strcmp(cast, "string") != 0) {
/* Non string type is OK */
tvar->type = strdup(cast);
return (tvar->type == NULL) ? -ENOMEM : 0;
}
if (die_get_bit_size(vr_die) != 0) {
/* This is a bitfield */
ret = snprintf(buf, 16, "b%d@%d/%zd", die_get_bit_size(vr_die),
die_get_bit_offset(vr_die),
BYTES_TO_BITS(die_get_byte_size(vr_die)));
goto formatted;
}
if (die_get_real_type(vr_die, &type) == NULL) {
pr_warning("Failed to get a type information of %s.\n",
dwarf_diename(vr_die));
return -ENOENT;
}
pr_debug("%s type is %s.\n",
dwarf_diename(vr_die), dwarf_diename(&type));
if (cast && strcmp(cast, "string") == 0) { /* String type */
ret = dwarf_tag(&type);
if (ret != DW_TAG_pointer_type &&
ret != DW_TAG_array_type) {
pr_warning("Failed to cast into string: "
"%s(%s) is not a pointer nor array.\n",
dwarf_diename(vr_die), dwarf_diename(&type));
return -EINVAL;
}
if (ret == DW_TAG_pointer_type) {
if (die_get_real_type(&type, &type) == NULL) {
pr_warning("Failed to get a type"
" information.\n");
return -ENOENT;
}
while (*ref_ptr)
ref_ptr = &(*ref_ptr)->next;
/* Add new reference with offset +0 */
*ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
if (*ref_ptr == NULL) {
pr_warning("Out of memory error\n");
return -ENOMEM;
}
}
if (!die_compare_name(&type, "char") &&
!die_compare_name(&type, "unsigned char")) {
pr_warning("Failed to cast into string: "
"%s is not (unsigned) char *.\n",
dwarf_diename(vr_die));
return -EINVAL;
}
tvar->type = strdup(cast);
return (tvar->type == NULL) ? -ENOMEM : 0;
}
ret = BYTES_TO_BITS(die_get_byte_size(&type));
if (!ret)
/* No size ... try to use default type */
return 0;
/* Check the bitwidth */
if (ret > MAX_BASIC_TYPE_BITS) {
pr_info("%s exceeds max-bitwidth. Cut down to %d bits.\n",
dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
ret = MAX_BASIC_TYPE_BITS;
}
ret = snprintf(buf, 16, "%c%d",
die_is_signed_type(&type) ? 's' : 'u', ret);
formatted:
if (ret < 0 || ret >= 16) {
if (ret >= 16)
ret = -E2BIG;
pr_warning("Failed to convert variable type: %s\n",
strerror(-ret));
return ret;
}
tvar->type = strdup(buf);
if (tvar->type == NULL)
return -ENOMEM;
return 0;
}
