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dwarf_prototypes.c
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dwarf_prototypes.c
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/* Copyright Dima Kogan <[email protected]>
*
* This program is free software; you can redistribute it and/or modify it under
* the terms of version 2 of the GNU General Public License as published by the
* Free Software Foundation.
*
*/
#include <stdio.h>
#include <elfutils/libdwfl.h>
#include <dwarf.h>
#include <inttypes.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include "config.h"
#include "debug.h"
#include "dict.h"
#include "expr.h"
#include "filter.h"
#include "lens.h"
#include "lens_default.h"
#include "lens_enum.h"
#include "library.h"
#include "options.h"
#include "param.h"
#include "prototype.h"
#include "type.h"
#include "value.h"
#define complain(die, format, ...) \
debug(DEBUG_FUNCTION, "%s() die '%s' @ 0x%" PRIx64 ": " format, \
__func__, dwarf_diename(die), dwarf_dieoffset(die), \
##__VA_ARGS__)
#define NEXT_SIBLING(die) \
int res = dwarf_siblingof(die, die); \
if (res == 0) continue; /* sibling exists */ \
if (res < 0) return false; /* error */ \
break /* no sibling exists */
static struct arg_type_info *get_type(int *newly_allocated_info,
Dwarf_Die *type_die,
struct protolib *plib,
struct dict *type_dieoffset_hash);
// debugging functions to dump types that I already parsed
#ifdef DUMP_PROTOTYPES
static bool _dump_ltrace_tree(const struct arg_type_info *info, int indent)
{
if (indent > 7) {
fprintf(stderr, "%*s%p ...\n", indent*4, "", (void*)info);
return true;
}
if (info == NULL) {
fprintf(stderr, "%*s%p NULL\n", indent*4, "", (void*)info);
return true;
}
switch (info->type) {
case ARGTYPE_VOID:
fprintf(stderr, "%*s%p void\n", indent*4, "", (void*)info);
break;
case ARGTYPE_INT:
case ARGTYPE_UINT:
case ARGTYPE_LONG:
case ARGTYPE_ULONG:
case ARGTYPE_CHAR:
case ARGTYPE_SHORT:
case ARGTYPE_USHORT:
case ARGTYPE_FLOAT:
case ARGTYPE_DOUBLE:
fprintf(stderr, "%*s%p base\n", indent*4, "", (void*)info);
break;
case ARGTYPE_ARRAY:
fprintf(stderr, "%*s%p array. elements not printed\n", indent*4,
"", (void*)info);
break;
case ARGTYPE_POINTER:
fprintf(stderr, "%*s%p pointer to...\n", indent*4,
"", (void*)info);
_dump_ltrace_tree(info->u.ptr_info.info, indent+1);
break;
case ARGTYPE_STRUCT:
fprintf(stderr, "%*s%p struct...\n", indent*4,
"", (void*)info);
struct struct_field
{
struct arg_type_info *info;
int own_info;
} *elements = (struct struct_field*)info->u.entries.data;
unsigned int i;
for(i=0; i<info->u.entries.size; i++)
_dump_ltrace_tree(elements[i].info, indent+1);
break;
default:
fprintf(stderr, "%*s%p unknown type\n", indent*4,
"", (void*)info);
return false;;
}
return true;
}
static bool dump_ltrace_tree(const struct arg_type_info *info)
{
return _dump_ltrace_tree(info, 0);
}
#endif
// pulls a numerical value out of a particular attribute in a die. Returns true
// if successful. The result is returned in *result. Note that this is cast to
// (uint64_t), regardless of the actual type of the input
static bool get_die_numeric(uint64_t *result,
Dwarf_Die *die, unsigned int attr_name)
{
Dwarf_Attribute attr ;
union {
Dwarf_Word udata;
Dwarf_Sword sdata;
Dwarf_Addr addr;
bool flag;
} u;
if (dwarf_attr(die, attr_name, &attr) == NULL)
return false;
unsigned int form = dwarf_whatform(&attr);
#define PROCESS_NUMERIC(type) \
if (dwarf_form ## type(&attr, &u.type) != 0) \
return false; \
*result = (uint64_t)u.type; \
return true
switch (form) {
case DW_FORM_addr:
PROCESS_NUMERIC(addr);
case DW_FORM_data1:
case DW_FORM_data2:
case DW_FORM_data4:
case DW_FORM_data8:
case DW_FORM_udata:
PROCESS_NUMERIC(udata);
case DW_FORM_sdata:
PROCESS_NUMERIC(sdata);
case DW_FORM_flag:
PROCESS_NUMERIC(flag);
default:
complain(die, "Unknown numeric form %d for attr_name: %d",
form, attr_name);
return false;
}
#undef PROCESS_NUMERIC
}
static bool get_integer_base_type(enum arg_type *type, int byte_size,
bool is_signed)
{
// not using a switch() here because sizeof(int) == sizeof(long) on some
// architectures, and removing that case for those arches is a pain
if (byte_size == sizeof(char)) {
*type = ARGTYPE_CHAR;
return true;
}
if (byte_size == sizeof(short)) {
*type = is_signed ? ARGTYPE_SHORT : ARGTYPE_USHORT;
return true;
}
if (byte_size == sizeof(int)) {
*type = is_signed ? ARGTYPE_INT : ARGTYPE_UINT;
return true;
}
if (byte_size == sizeof(long)) {
*type = is_signed ? ARGTYPE_LONG : ARGTYPE_ULONG;
return true;
}
return false;
}
// returns an ltrace ARGTYPE_XXX base type from the given die. If we dont
// support a particular type (or an error occurred), I regturn ARGTYPE_VOID
static enum arg_type get_base_type(Dwarf_Die *die)
{
uint64_t encoding;
if (!get_die_numeric(&encoding, die, DW_AT_encoding))
return ARGTYPE_VOID;
if (encoding == DW_ATE_void)
return ARGTYPE_VOID;
if (encoding == DW_ATE_signed_char || encoding == DW_ATE_unsigned_char)
return ARGTYPE_CHAR;
uint64_t byte_size;
if (!get_die_numeric(&byte_size, die, DW_AT_byte_size))
return ARGTYPE_VOID;
if (encoding == DW_ATE_signed ||
encoding == DW_ATE_unsigned ||
encoding == DW_ATE_boolean) {
bool is_signed = (encoding == DW_ATE_signed);
enum arg_type type;
if (!get_integer_base_type(&type, (int)byte_size, is_signed)) {
complain(die, "Unknown integer base type. "
"Using 'void'");
return ARGTYPE_VOID;
}
return type;
}
if (encoding == DW_ATE_float) {
switch (byte_size) {
case sizeof(float):
return ARGTYPE_FLOAT;
case sizeof(double):
return ARGTYPE_DOUBLE;
default:
// things like long doubles. ltrace has no support yet,
// so I just say "void"
return ARGTYPE_VOID;
}
}
#if 0
if (encoding == DW_ATE_complex_float) {
switch (byte_size) {
case 2*sizeof(float):
return ARGTYPE_FLOAT;
case 2*sizeof(double):
return ARGTYPE_DOUBLE;
default:
// things like long doubles. ltrace has no support yet,
// so I just say "void"
return ARGTYPE_VOID;
}
}
#endif
// Unknown encoding. I just say void
complain(die, "Unknown base type. Returning 'void'");
return ARGTYPE_VOID;
}
static bool get_type_die(Dwarf_Die *type_die, Dwarf_Die *die)
{
Dwarf_Attribute attr;
return
dwarf_attr(die, DW_AT_type, &attr) != NULL &&
dwarf_formref_die(&attr, type_die) != NULL;
}
// type_dieoffset_hash dictionary callbacks
static size_t dwarf_die_hash(const void *x)
{
return *(const Dwarf_Off*)x;
}
static int dwarf_die_eq(const void *a, const void *b)
{
return *(const Dwarf_Off*)a == *(const Dwarf_Off*)b;
}
// returns a newly-allocated art_type_info*, or NULL on error
static struct arg_type_info *get_enum(Dwarf_Die *parent,
struct dict *type_dieoffset_hash)
{
#define CLEANUP_AND_RETURN_ERROR(ret) do { \
if (dupkey != NULL) \
free((void*)dupkey); \
if (value != NULL) { \
value_destroy(value); \
free(value); \
} \
if (lens != NULL) { \
lens_destroy(&lens->super); \
free(lens); \
} \
if (result != NULL) { \
type_destroy(result); \
free(result); \
} \
dict_erase (type_dieoffset_hash, &die_offset, NULL, \
NULL, NULL); \
dict_insert(type_dieoffset_hash, &die_offset, \
&(struct arg_type_info*){ \
type_get_simple(ARGTYPE_VOID)}); \
return ret; \
} while (0)
struct arg_type_info *result = NULL;
struct enum_lens *lens = NULL;
const char *dupkey = NULL;
struct value *value = NULL;
Dwarf_Off die_offset = dwarf_dieoffset(parent);
result = calloc(1, sizeof(struct arg_type_info));
if (result == NULL) {
complain(parent, "alloc error");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (dict_insert(type_dieoffset_hash, &die_offset, &result) != 0) {
complain(parent, "Couldn't insert into cache dict");
CLEANUP_AND_RETURN_ERROR(NULL);
}
uint64_t byte_size;
if (!get_die_numeric(&byte_size, parent, DW_AT_byte_size)) {
// No byte size given, assume 'int'
result->type = ARGTYPE_INT;
} else {
if (!get_integer_base_type(&result->type,
(int)byte_size, true)) {
complain(parent, "Unknown integer base type. "
"Using 'int'");
result->type = ARGTYPE_INT;
}
}
lens = calloc(1, sizeof(struct enum_lens));
if (lens == NULL) {
complain(parent, "alloc error");
CLEANUP_AND_RETURN_ERROR(NULL);
}
lens_init_enum(lens);
result->lens = &lens->super;
result->own_lens = 1;
Dwarf_Die die;
if (dwarf_child(parent, &die) != 0) {
// empty enum. we're done
CLEANUP_AND_RETURN_ERROR(NULL);
}
while (1) {
complain(&die, "enum element: 0x%02x/'%s'", dwarf_tag(&die),
dwarf_diename(&die));
dupkey = NULL;
value = NULL;
if (dwarf_tag(&die) != DW_TAG_enumerator) {
complain(&die, "Enums can have ONLY DW_TAG_enumerator "
"elements");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (!dwarf_hasattr(&die, DW_AT_const_value)) {
complain(&die, "Enums MUST have DW_AT_const_value "
"values");
CLEANUP_AND_RETURN_ERROR(NULL);
}
const char *key = dwarf_diename(&die);
if (key == NULL) {
complain(&die, "Enums must have a DW_AT_name key");
CLEANUP_AND_RETURN_ERROR(NULL);
}
dupkey = strdup(key);
if (dupkey == NULL) {
complain(&die, "Couldn't duplicate enum key");
CLEANUP_AND_RETURN_ERROR(NULL);
}
value = calloc(1, sizeof(struct value));
if (value == NULL) {
complain(&die, "Couldn't alloc enum value");
CLEANUP_AND_RETURN_ERROR(NULL);
}
value_init_detached(value, NULL, type_get_simple(result->type),
0);
uint64_t enum_value;
if (!get_die_numeric(&enum_value, &die, DW_AT_const_value)) {
complain(&die, "Couldn't get enum value");
CLEANUP_AND_RETURN_ERROR(NULL);
}
value_set_word(value, (long)enum_value);
if (lens_enum_add(lens, dupkey, 1, value, 1)) {
complain(&die, "Couldn't add enum element");
CLEANUP_AND_RETURN_ERROR(NULL);
}
NEXT_SIBLING(&die);
}
return result;
#undef CLEANUP_AND_RETURN_ERROR
}
// returns a newly-allocated art_type_info*, or NULL on error
static struct arg_type_info *get_array(Dwarf_Die *parent,
struct protolib *plib,
struct dict *type_dieoffset_hash)
{
#define CLEANUP_AND_RETURN_ERROR(ret) do { \
if (length != NULL) { \
expr_destroy(length); \
free(length); \
} \
if (array_type != NULL && newly_allocated_array_type) { \
type_destroy(array_type); \
free(array_type); \
} \
if (result != NULL) { \
type_destroy(result); \
free(result); \
} \
dict_erase (type_dieoffset_hash, &die_offset, \
NULL, NULL, NULL); \
dict_insert(type_dieoffset_hash, &die_offset, \
&(struct arg_type_info*){ \
type_get_simple(ARGTYPE_VOID)}); \
return ret; \
} while (0)
struct arg_type_info *result = NULL;
struct expr_node *length = NULL;
struct arg_type_info *array_type = NULL;
int newly_allocated_array_type = 0;
Dwarf_Off die_offset = dwarf_dieoffset(parent);
result = calloc(1, sizeof(struct arg_type_info));
if (result == NULL) {
complain(parent, "alloc error");
CLEANUP_AND_RETURN_ERROR(NULL);
}
Dwarf_Die type_die;
if (!get_type_die(&type_die, parent)) {
complain(parent, "Array has unknown type");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (dict_insert(type_dieoffset_hash, &die_offset, &result) != 0) {
complain(parent, "Couldn't insert into cache dict");
CLEANUP_AND_RETURN_ERROR(NULL);
}
array_type = get_type(&newly_allocated_array_type,
&type_die, plib, type_dieoffset_hash);
if (array_type == NULL) {
complain(parent, "Couldn't figure out array's type");
CLEANUP_AND_RETURN_ERROR(NULL);
}
Dwarf_Die subrange;
if (dwarf_child(parent, &subrange) != 0) {
complain(parent,
"Array must have a DW_TAG_subrange_type child, "
"but has none");
CLEANUP_AND_RETURN_ERROR(NULL);
}
Dwarf_Die next_subrange;
if (dwarf_siblingof(&subrange, &next_subrange) <= 0) {
complain(parent,
"Array must have exactly one DW_TAG_subrange_type "
"child");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (dwarf_hasattr(&subrange, DW_AT_lower_bound)) {
uint64_t lower_bound;
if (!get_die_numeric(&lower_bound, &subrange,
DW_AT_lower_bound)) {
complain(parent, "Couldn't read lower bound");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (lower_bound != 0) {
complain(parent,
"Array subrange has a nonzero lower bound. "
"Don't know what to do");
CLEANUP_AND_RETURN_ERROR(NULL);
}
}
uint64_t N;
if (!dwarf_hasattr(&subrange, DW_AT_upper_bound)) {
// no upper bound is defined. This is probably a variable-width
// array, and I don't know how long it is. Let's say 0 to be
// safe
N = 0;
}
else
{
if (!get_die_numeric(&N, &subrange, DW_AT_upper_bound)) {
complain(parent, "Couldn't read upper bound");
CLEANUP_AND_RETURN_ERROR(NULL);
}
N++;
}
// I'm not checking the subrange type. It should be some sort of
// integer, and I don't know what it would mean for it to be something
// else
length = calloc(1, sizeof(struct expr_node));
if (length == NULL) {
complain(&subrange, "Couldn't alloc length expr");
CLEANUP_AND_RETURN_ERROR(NULL);
}
expr_init_const_word(length, N, type_get_simple(ARGTYPE_INT), 0);
type_init_array(result, array_type, newly_allocated_array_type,
length, 1);
return result;
#undef CLEANUP_AND_RETURN_ERROR
}
// returns a newly-allocated art_type_info*, or NULL on error
static struct arg_type_info *get_structure(Dwarf_Die *parent,
struct protolib *plib,
struct dict *type_dieoffset_hash)
{
#define CLEANUP_AND_RETURN_ERROR(ret) do { \
if (member_type != NULL && newly_allocated_member_type) { \
type_destroy(member_type); \
free(member_type); \
} \
if (result != NULL) { \
type_destroy(result); \
free(result); \
} \
dict_erase (type_dieoffset_hash, &die_offset, \
NULL, NULL, NULL); \
dict_insert(type_dieoffset_hash, &die_offset, \
&(struct arg_type_info*){ \
type_get_simple(ARGTYPE_VOID)}); \
return ret; \
} while (0)
struct arg_type_info *result = NULL;
struct arg_type_info *member_type = NULL;
int newly_allocated_member_type = 0;
Dwarf_Off die_offset = dwarf_dieoffset(parent);
result = calloc(1, sizeof(struct arg_type_info));
if (result == NULL) {
complain(parent, "alloc error");
CLEANUP_AND_RETURN_ERROR(NULL);
}
type_init_struct(result);
if (dict_insert(type_dieoffset_hash, &die_offset, &result) != 0) {
complain(parent, "Couldn't insert into cache dict");
CLEANUP_AND_RETURN_ERROR(NULL);
}
Dwarf_Die die;
if (dwarf_child(parent, &die) != 0) {
// no elements; we're done
return result;
}
while (1) {
member_type = NULL;
newly_allocated_member_type = 0;
complain(&die, "member: 0x%02x", dwarf_tag(&die));
if (dwarf_tag(&die) != DW_TAG_member) {
complain(&die, "Structure can have ONLY DW_TAG_member");
CLEANUP_AND_RETURN_ERROR(NULL);
}
Dwarf_Die type_die;
if (!get_type_die(&type_die, &die)) {
complain(&die, "Couldn't get type of element");
CLEANUP_AND_RETURN_ERROR(NULL);
}
member_type = get_type(&newly_allocated_member_type,
&type_die, plib, type_dieoffset_hash);
if (member_type == NULL) {
complain(&die, "Couldn't parse type from DWARF data");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (member_type->type == ARGTYPE_VOID) {
complain(&die, "Struct member has void type. "
"Giving up on this structure");
CLEANUP_AND_RETURN_ERROR(NULL);
}
if (type_struct_add(result, member_type,
newly_allocated_member_type) != 0) {
complain(&die, "Couldn't add type to struct");
CLEANUP_AND_RETURN_ERROR(NULL);
}
NEXT_SIBLING(&die);
}
return result;
#undef CLEANUP_AND_RETURN_ERROR
}
// Reads the type in the die and returns the corresponding arg_type_info*. If
// this was newly allocated on the heap, *newly_allocated_info = true. If an
// error occurred, returns NULL
static struct arg_type_info *get_type(int *newly_allocated_result,
Dwarf_Die *type_die,
struct protolib *plib,
struct dict *type_dieoffset_hash)
{
#define CLEANUP_AND_RETURN_ERROR(ret) do { \
if (pointee != NULL && newly_allocated_pointee) { \
type_destroy(pointee); \
free(pointee); \
} \
if (result != NULL && *newly_allocated_result) { \
type_destroy(result); \
free(result); \
} \
dict_erase (type_dieoffset_hash, &die_offset, \
NULL, NULL, NULL); \
dict_insert(type_dieoffset_hash, &die_offset, \
&(struct arg_type_info*){ \
type_get_simple(ARGTYPE_VOID)}); \
return ret; \
} while (0)
#define DICT_INSERT_AND_CHECK(type_dieoffset_hash, die_offset, result) \
do { \
if (dict_insert(type_dieoffset_hash, \
die_offset, result) != 0) { \
complain(type_die, \
"Couldn't insert into cache dict"); \
CLEANUP_AND_RETURN_ERROR(NULL); \
} \
} while(0)
struct arg_type_info *result = NULL;
struct arg_type_info *pointee = NULL;
int newly_allocated_pointee = 0;
Dwarf_Off die_offset = dwarf_dieoffset(type_die);
// by default, we say we allocated nothing. I set this to true later,
// when I allocate memory
*newly_allocated_result = 0;
struct arg_type_info **found_type = dict_find(type_dieoffset_hash,
&die_offset);
if (found_type != NULL) {
complain(type_die, "Read pre-computed type");
return *found_type;
}
const char *type_name = dwarf_diename(type_die);
if (type_name != NULL) {
struct named_type *already_defined_type =
protolib_lookup_type(plib, type_name, true);
if (already_defined_type != NULL) {
complain(type_die,
"Type '%s' defined in a .conf file. "
"Using that instead of DWARF",
type_name);
return already_defined_type->info;
}
}
Dwarf_Die next_die;
switch (dwarf_tag(type_die)) {
case DW_TAG_base_type:
complain(type_die, "Storing base type");
result = type_get_simple(get_base_type(type_die));
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
case DW_TAG_subroutine_type:
case DW_TAG_inlined_subroutine:
// function pointers are stored as void*. If ltrace tries to
// dereference these, it'll get a segfault
complain(type_die, "Storing subroutine type");
result = type_get_simple(ARGTYPE_VOID);
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
case DW_TAG_pointer_type:
if (!get_type_die(&next_die, type_die)) {
// the pointed-to type isn't defined, so I report a
// void*
complain(type_die, "Storing void-pointer type");
result = type_get_voidptr();
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
}
complain(type_die, "Storing pointer type");
*newly_allocated_result = 1;
result = calloc(1, sizeof(struct arg_type_info));
if (result == NULL) {
complain(type_die, "alloc error");
CLEANUP_AND_RETURN_ERROR(NULL);
}
/* Make it at least look like a pointer, so that
* e.g. alignment and sizeof can be computed when
* needed, and so that it doesn't look as if we're
* adding bare voids to structures. */
result->type = ARGTYPE_POINTER;
result->u.ptr_info.info = NULL;
/* Add it now so that recursive requests for this type
* don't end up spinning endlessly. */
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
/* Now we can safely recurse. */
pointee = get_type(&newly_allocated_pointee,
&next_die, plib, type_dieoffset_hash);
if (pointee == NULL)
CLEANUP_AND_RETURN_ERROR(NULL);
/* Update the stored type in-place. */
type_init_pointer(result, pointee, newly_allocated_pointee);
complain(type_die, "Done storing pointer type.");
return result;
case DW_TAG_structure_type:
complain(type_die, "Storing struct type");
*newly_allocated_result = 1;
result = get_structure(type_die, plib, type_dieoffset_hash);
if (result == NULL)
CLEANUP_AND_RETURN_ERROR(NULL);
return result;
case DW_TAG_typedef:
case DW_TAG_const_type:
case DW_TAG_volatile_type:
// Various tags are simply pass-through, so I just keep going
if (get_type_die(&next_die, type_die)) {
complain(type_die, "Storing const/typedef type");
result = get_type(newly_allocated_result, &next_die,
plib, type_dieoffset_hash);
if (result == NULL)
CLEANUP_AND_RETURN_ERROR(NULL);
} else {
// no type. Use 'void'. Normally I'd think this is
// bogus, but stdio typedefs something to void
result = type_get_simple(ARGTYPE_VOID);
complain(type_die, "Storing void type");
}
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
case DW_TAG_enumeration_type:
// We have an enumeration. This has a base type, but has a
// particular lens to handle the enum
*newly_allocated_result = 1;
complain(type_die, "Storing enum int");
result = get_enum(type_die, type_dieoffset_hash);
if (result == NULL)
CLEANUP_AND_RETURN_ERROR(NULL);
return result;
case DW_TAG_array_type:
*newly_allocated_result = 1;
complain(type_die, "Storing array");
result = get_array(type_die, plib, type_dieoffset_hash);
if (result == NULL)
CLEANUP_AND_RETURN_ERROR(NULL);
return result;
case DW_TAG_union_type:
{
uint64_t sz;
if (! get_die_numeric(&sz, type_die, DW_AT_byte_size)) {
complain(type_die, "Can't determine type size");
CLEANUP_AND_RETURN_ERROR(NULL);
} else if (sz != (uint64_t) (unsigned long) sz) {
complain(type_die, "Union size too big");
CLEANUP_AND_RETURN_ERROR(NULL);
} else {
complain(type_die, "Storing union as byte array");
*newly_allocated_result = 1;
/* Allocate the array type and its element
* type in one bunch. */
result = calloc(2, sizeof *result);
struct expr_node *len_expr = calloc(1, sizeof *len_expr);
if (result == NULL || len_expr == NULL) {
complain(type_die, "alloc error");
free(result);
free(len_expr);
CLEANUP_AND_RETURN_ERROR(NULL);
}
result[1].type = ARGTYPE_CHAR;
result[1].lens = &hex_lens;
result[1].own_lens = 0;
expr_init_const_word(len_expr, (unsigned long) sz,
type_get_simple(ARGTYPE_ULONG), 0);
/* Don't own element type, own length. */
type_init_array(&result[0], &result[1], 0, len_expr, 1);
}
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
}
default:
complain(type_die, "Unknown type tag 0x%x. Returning void",
dwarf_tag(type_die));
result = type_get_simple(ARGTYPE_VOID);
DICT_INSERT_AND_CHECK(type_dieoffset_hash, &die_offset, &result);
return result;
}
#undef DICT_INSERT_AND_CHECK
#undef CLEANUP_AND_RETURN_ERROR
}
// fills in *proto with a prototype. Returns true on success
static bool get_prototype(struct prototype *result,
Dwarf_Die *subroutine, struct protolib *plib,
struct dict *type_dieoffset_hash)
{
#define CLEANUP_AND_RETURN_ERROR(ret) do { \
if (argument_type != NULL && newly_allocated_argument_type) { \
type_destroy(argument_type); \
free(argument_type); \
} \
prototype_destroy(result); \
return ret; \
} while (0)
struct arg_type_info *argument_type = NULL;
int newly_allocated_argument_type = 0;
prototype_init(result);
// First, look at the return type. This is stored in a DW_AT_type tag in
// the subroutine DIE. If there is no such tag, this function returns
// void
Dwarf_Die return_type_die;
if (!get_type_die(&return_type_die, subroutine)) {
result->return_info = type_get_simple(ARGTYPE_VOID);
result->own_return_info = 0;
} else {
int newly_allocated_return_type;
result->return_info = get_type(&newly_allocated_return_type,
&return_type_die, plib,
type_dieoffset_hash);
if (result->return_info == NULL) {
complain(subroutine, "Couldn't get return type");
CLEANUP_AND_RETURN_ERROR(false);
}
result->own_return_info = newly_allocated_return_type;
}
// Now look at the arguments
Dwarf_Die arg_die;
if (dwarf_child(subroutine, &arg_die) != 0) {
// no args. We're done
return true;
}
while (1) {
if (dwarf_tag(&arg_die) == DW_TAG_formal_parameter) {
complain(&arg_die, "arg: 0x%02x", dwarf_tag(&arg_die));
argument_type = NULL;
newly_allocated_argument_type = false;
Dwarf_Die type_die;
if (!get_type_die(&type_die, &arg_die)) {
complain(&arg_die, "Couldn't get the argument "
"type die");
CLEANUP_AND_RETURN_ERROR(false);
}
argument_type = get_type(&newly_allocated_argument_type,
&type_die, plib,
type_dieoffset_hash);
if (argument_type==NULL) {
complain(&arg_die, "Couldn't parse arg "
"type from DWARF data");
CLEANUP_AND_RETURN_ERROR(false);
}
struct param param;
param_init_type(¶m, argument_type,
newly_allocated_argument_type);
if (prototype_push_param(result, ¶m) <0) {
complain(&arg_die, "couldn't add argument to "
"the prototype");
CLEANUP_AND_RETURN_ERROR(false);
}
#ifdef DUMP_PROTOTYPES
fprintf(stderr, "Adding argument:\n");
dump_ltrace_tree(argument_type);
#endif
}
NEXT_SIBLING(&arg_die);
}
return true;
#undef CLEANUP_AND_RETURN_ERROR
}
static enum callback_status
any_filter_matches_function_cb(const char *name, void *data)
{
struct library *lib = (struct library*)data;
return CBS_STOP_IF(
filter_matches_symbol(options.plt_filter, name, lib) ||
filter_matches_symbol(options.static_filter, name, lib) ||
filter_matches_symbol(options.export_filter, name, lib));
}
static bool any_filter_matches_function(const char *function_name,
struct library *lib,
Dwarf_Die *die)
{
// I give up if this function is not wanted AND if none of its aliased
// names are wanted
if (any_filter_matches_function_cb(function_name, lib) == CBS_STOP)
return true;
// prototype not found. Is it aliased?
if (library_exported_names_each_alias(&lib->exported_names,
function_name, NULL,
any_filter_matches_function_cb,
lib) != NULL)
return true;
complain(die, "Prototype not requested by any filter");
return false;
}
static bool import_subprogram_name(struct protolib *plib, struct library *lib,
struct dict *type_dieoffset_hash,
Dwarf_Die *die, const char *function_name)
{
if (!any_filter_matches_function( function_name, lib, die)) {
complain(die, "Prototype not requested by any filter");