type.c 14.6 KB
Newer Older
1 2
/*
 * This file is part of ltrace.
3
 * Copyright (C) 2011,2012,2013,2015 Petr Machata, Red Hat Inc.
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
 * Copyright (C) 2007,2008 Juan Cespedes
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <assert.h>
#include <stdlib.h>
24
#include <limits.h>
25 26 27

#include "type.h"
#include "sysdep.h"
28
#include "expr.h"
Petr Machata's avatar
Petr Machata committed
29
#include "lens.h"
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61

struct arg_type_info *
type_get_simple(enum arg_type type)
{
#define HANDLE(T) {					\
		static struct arg_type_info t = { T };	\
	case T:						\
		return &t;				\
	}

	switch (type) {
	HANDLE(ARGTYPE_VOID)
	HANDLE(ARGTYPE_INT)
	HANDLE(ARGTYPE_UINT)
	HANDLE(ARGTYPE_LONG)
	HANDLE(ARGTYPE_ULONG)
	HANDLE(ARGTYPE_CHAR)
	HANDLE(ARGTYPE_SHORT)
	HANDLE(ARGTYPE_USHORT)
	HANDLE(ARGTYPE_FLOAT)
	HANDLE(ARGTYPE_DOUBLE)

#undef HANDLE

	case ARGTYPE_ARRAY:
	case ARGTYPE_STRUCT:
	case ARGTYPE_POINTER:
		assert(!"Not a simple type!");
	};
	abort();
}

62 63 64 65 66 67 68 69 70 71 72 73 74
struct arg_type_info *
type_get_voidptr(void)
{
	struct arg_type_info *void_info = type_get_simple(ARGTYPE_VOID);
	static struct arg_type_info *ret;
	if (ret == NULL) {
		static struct arg_type_info ptr_info;
		type_init_pointer(&ptr_info, void_info, 0);
		ret = &ptr_info;
	}
	return ret;
}

Petr Machata's avatar
Petr Machata committed
75 76 77 78 79 80 81 82
static void
type_init_common(struct arg_type_info *info, enum arg_type type)
{
	info->type = type;
	info->lens = NULL;
	info->own_lens = 0;
}

83 84 85 86 87 88 89 90
struct struct_field {
	struct arg_type_info *info;
	int own_info;
};

void
type_init_struct(struct arg_type_info *info)
{
Petr Machata's avatar
Petr Machata committed
91
	type_init_common(info, ARGTYPE_STRUCT);
92 93 94 95 96 97 98 99
	VECT_INIT(&info->u.entries, struct struct_field);
}

int
type_struct_add(struct arg_type_info *info,
		struct arg_type_info *field_info, int own)
{
	assert(info->type == ARGTYPE_STRUCT);
100
	assert(field_info->type != ARGTYPE_VOID);
101 102 103 104 105 106 107 108
	struct struct_field field = { field_info, own };
	return VECT_PUSHBACK(&info->u.entries, &field);
}

struct arg_type_info *
type_struct_get(struct arg_type_info *info, size_t idx)
{
	assert(info->type == ARGTYPE_STRUCT);
109
	return VECT_ELEMENT(&info->u.entries, struct struct_field, idx)->info;
110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135
}

size_t
type_struct_size(struct arg_type_info *info)
{
	assert(info->type == ARGTYPE_STRUCT);
	return vect_size(&info->u.entries);
}

static void
struct_field_dtor(struct struct_field *field, void *data)
{
	if (field->own_info) {
		type_destroy(field->info);
		free(field->info);
	}
}

static void
type_struct_destroy(struct arg_type_info *info)
{
	VECT_DESTROY(&info->u.entries, struct struct_field,
		     struct_field_dtor, NULL);
}

static int
136
layout_struct(struct process *proc, struct arg_type_info *info,
137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187
	      size_t *sizep, size_t *alignmentp, size_t *offsetofp)
{
	size_t sz = 0;
	size_t max_alignment = 0;
	size_t i;
	size_t offsetof_field = (size_t)-1;
	if (offsetofp != NULL)
		offsetof_field = *offsetofp;

	assert(info->type == ARGTYPE_STRUCT);
	for (i = 0; i < vect_size(&info->u.entries); ++i) {
		struct struct_field *field
			= VECT_ELEMENT(&info->u.entries,
				       struct struct_field, i);

		size_t alignment = type_alignof(proc, field->info);
		if (alignment == (size_t)-1)
			return -1;

		/* Add padding to SZ to align the next element.  */
		sz = align(sz, alignment);
		if (i == offsetof_field) {
			*offsetofp = sz;
			if (sizep == NULL && alignmentp == NULL)
				return 0;
		}

		size_t size = type_sizeof(proc, field->info);
		if (size == (size_t)-1)
			return -1;
		sz += size;

		if (alignment > max_alignment)
			max_alignment = alignment;
	}

	if (max_alignment > 0)
		sz = align(sz, max_alignment);

	if (sizep != NULL)
		*sizep = sz;

	if (alignmentp != NULL)
		*alignmentp = max_alignment;

	return 0;
}

void
type_init_array(struct arg_type_info *info,
		struct arg_type_info *element_info, int own_info,
188
		struct expr_node *length_expr, int own_length)
189
{
Petr Machata's avatar
Petr Machata committed
190
	type_init_common(info, ARGTYPE_ARRAY);
191 192
	info->u.array_info.elt_type = element_info;
	info->u.array_info.own_info = own_info;
193
	info->u.array_info.length = length_expr;
194
	info->u.array_info.own_length = own_length;
195 196 197 198 199 200 201 202 203 204 205 206 207
}

static void
type_array_destroy(struct arg_type_info *info)
{
	if (info->u.array_info.own_info) {
		type_destroy(info->u.array_info.elt_type);
		free(info->u.array_info.elt_type);
	}
	if (info->u.array_info.own_length) {
		expr_destroy(info->u.array_info.length);
		free(info->u.array_info.length);
	}
208 209
}

210 211 212 213
void
type_init_pointer(struct arg_type_info *info,
		  struct arg_type_info *pointee_info, int own_info)
{
Petr Machata's avatar
Petr Machata committed
214
	type_init_common(info, ARGTYPE_POINTER);
215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258
	info->u.ptr_info.info = pointee_info;
	info->u.ptr_info.own_info = own_info;
}

static void
type_pointer_destroy(struct arg_type_info *info)
{
	if (info->u.ptr_info.own_info) {
		type_destroy(info->u.ptr_info.info);
		free(info->u.ptr_info.info);
	}
}

void
type_destroy(struct arg_type_info *info)
{
	if (info == NULL)
		return;

	switch (info->type) {
	case ARGTYPE_STRUCT:
		type_struct_destroy(info);
		break;

	case ARGTYPE_ARRAY:
		type_array_destroy(info);
		break;

	case ARGTYPE_POINTER:
		type_pointer_destroy(info);
		break;

	case ARGTYPE_VOID:
	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:
		break;
	}
Petr Machata's avatar
Petr Machata committed
259 260 261 262 263

	if (info->own_lens) {
		lens_destroy(info->lens);
		free(info->lens);
	}
264 265
}

266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354
static int
type_alloc_and_clone(struct arg_type_info **retpp,
		     struct arg_type_info *info, int own)
{
	*retpp = info;
	if (own) {
		*retpp = malloc(sizeof **retpp);
		if (*retpp == NULL || type_clone(*retpp, info) < 0) {
			free(*retpp);
			return -1;
		}
	}
	return 0;
}

static enum callback_status
clone_struct_add_field(const struct struct_field *field, void *data)
{
	struct arg_type_info *retp = data;
	struct arg_type_info *info;
	if (type_alloc_and_clone(&info, field->info, field->own_info) < 0) {
	fail:
		if (info != field->info)
			free(info);
		return CBS_STOP;
	}

	if (type_struct_add(retp, info, field->own_info) < 0) {
		if (field->own_info)
			type_destroy(info);
		goto fail;
	}

	return CBS_CONT;
}

int
type_clone(struct arg_type_info *retp, const struct arg_type_info *info)
{
	switch (info->type) {
	case ARGTYPE_STRUCT:
		type_init_struct(retp);
		if (VECT_EACH_CST(&info->u.entries, struct struct_field, NULL,
				  clone_struct_add_field, retp) != NULL) {
			type_destroy(retp);
			return -1;
		}
		break;

	case ARGTYPE_ARRAY:;
		struct arg_type_info *elt_type;
		if (type_alloc_and_clone(&elt_type, info->u.array_info.elt_type,
					 info->u.array_info.own_info) < 0)
			return -1;

		assert(!info->u.array_info.own_length); // XXXXXXX
		type_init_array(retp, elt_type, info->u.array_info.own_info,
				info->u.array_info.length,
				info->u.array_info.own_length);
		break;

	case ARGTYPE_POINTER:;
		struct arg_type_info *ninfo;
		if (type_alloc_and_clone(&ninfo, info->u.ptr_info.info,
					 info->u.ptr_info.own_info) < 0)
			return -1;
		type_init_pointer(retp, ninfo, info->u.ptr_info.own_info);
		break;

	case ARGTYPE_VOID:
	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:
		*retp = *info;
		break;
	}

	assert(!info->own_lens);
	retp->lens = info->lens;
	retp->own_lens = info->own_lens;
	return 0;
}

355
#ifdef ARCH_HAVE_SIZEOF
356
size_t arch_type_sizeof(struct process *proc, struct arg_type_info *arg);
357 358
#else
size_t
359
arch_type_sizeof(struct process *proc, struct arg_type_info *arg)
360 361 362 363 364 365 366
{
	/* Use default value.  */
	return (size_t)-2;
}
#endif

#ifdef ARCH_HAVE_ALIGNOF
367
size_t arch_type_alignof(struct process *proc, struct arg_type_info *arg);
368 369
#else
size_t
370
arch_type_alignof(struct process *proc, struct arg_type_info *arg)
371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390
{
	/* Use default value.  */
	return (size_t)-2;
}
#endif

/* We need to support alignments that are not power of two.  E.g. long
 * double on x86 has alignment of 12.  */
size_t
align(size_t sz, size_t alignment)
{
	assert(alignment != 0);

	if ((sz % alignment) != 0)
		sz = ((sz / alignment) + 1) * alignment;

	return sz;
}

size_t
391
type_sizeof(struct process *proc, struct arg_type_info *type)
392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428
{
	size_t arch_size = arch_type_sizeof(proc, type);
	if (arch_size != (size_t)-2)
		return arch_size;

	switch (type->type) {
		size_t size;
	case ARGTYPE_CHAR:
		return sizeof(char);

	case ARGTYPE_SHORT:
	case ARGTYPE_USHORT:
		return sizeof(short);

	case ARGTYPE_INT:
	case ARGTYPE_UINT:
		return sizeof(int);

	case ARGTYPE_LONG:
	case ARGTYPE_ULONG:
		return sizeof(long);

	case ARGTYPE_FLOAT:
		return sizeof(float);

	case ARGTYPE_DOUBLE:
		return sizeof(double);

	case ARGTYPE_STRUCT:
		if (layout_struct(proc, type, &size, NULL, NULL) < 0)
			return (size_t)-1;
		return size;

	case ARGTYPE_POINTER:
		return sizeof(void *);

	case ARGTYPE_ARRAY:
429
		if (expr_is_compile_constant(type->u.array_info.length)) {
430
			long l;
431
			if (expr_eval_constant(type->u.array_info.length,
432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460
					       &l) < 0)
				return -1;

			struct arg_type_info *elt_ti
				= type->u.array_info.elt_type;

			size_t elt_size = type_sizeof(proc, elt_ti);
			if (elt_size == (size_t)-1)
				return (size_t)-1;

			return ((size_t)l) * elt_size;

		} else {
			/* Flexible arrays don't count into the
			 * sizeof.  */
			return 0;
		}

	case ARGTYPE_VOID:
		return 0;
	}

	abort();
}

#undef alignof
#define alignof(field,st) ((size_t) ((char*) &st.field - (char*) &st))

size_t
461
type_alignof(struct process *proc, struct arg_type_info *type)
462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513
{
	size_t arch_alignment = arch_type_alignof(proc, type);
	if (arch_alignment != (size_t)-2)
		return arch_alignment;

	struct { char c; char C; } cC;
	struct { char c; short s; } cs;
	struct { char c; int i; } ci;
	struct { char c; long l; } cl;
	struct { char c; void* p; } cp;
	struct { char c; float f; } cf;
	struct { char c; double d; } cd;

	static size_t char_alignment = alignof(C, cC);
	static size_t short_alignment = alignof(s, cs);
	static size_t int_alignment = alignof(i, ci);
	static size_t long_alignment = alignof(l, cl);
	static size_t ptr_alignment = alignof(p, cp);
	static size_t float_alignment = alignof(f, cf);
	static size_t double_alignment = alignof(d, cd);

	switch (type->type) {
		size_t alignment;
	case ARGTYPE_LONG:
	case ARGTYPE_ULONG:
		return long_alignment;
	case ARGTYPE_CHAR:
		return char_alignment;
	case ARGTYPE_SHORT:
	case ARGTYPE_USHORT:
		return short_alignment;
	case ARGTYPE_FLOAT:
		return float_alignment;
	case ARGTYPE_DOUBLE:
		return double_alignment;
	case ARGTYPE_POINTER:
		return ptr_alignment;

	case ARGTYPE_ARRAY:
		return type_alignof(proc, type->u.array_info.elt_type);

	case ARGTYPE_STRUCT:
		if (layout_struct(proc, type, NULL, &alignment, NULL) < 0)
			return (size_t)-1;
		return alignment;

	default:
		return int_alignment;
	}
}

size_t
514
type_offsetof(struct process *proc, struct arg_type_info *type, size_t emt)
515 516
{
	assert(type->type == ARGTYPE_STRUCT
517
	       || type->type == ARGTYPE_ARRAY);
518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538

	switch (type->type) {
		size_t alignment;
		size_t size;
	case ARGTYPE_ARRAY:
		alignment = type_alignof(proc, type->u.array_info.elt_type);
		if (alignment == (size_t)-1)
			return (size_t)-1;

		size = type_sizeof(proc, type->u.array_info.elt_type);
		if (size == (size_t)-1)
			return (size_t)-1;

		return emt * align(size, alignment);

	case ARGTYPE_STRUCT:
		if (layout_struct(proc, type, NULL, NULL, &emt) < 0)
			return (size_t)-1;
		return emt;

	default:
539
		abort();
540 541 542 543 544 545 546
	}
}

struct arg_type_info *
type_element(struct arg_type_info *info, size_t emt)
{
	assert(info->type == ARGTYPE_STRUCT
547
	       || info->type == ARGTYPE_ARRAY);
548 549 550 551 552 553 554 555 556 557

	switch (info->type) {
	case ARGTYPE_ARRAY:
		return info->u.array_info.elt_type;

	case ARGTYPE_STRUCT:
		assert(emt < type_struct_size(info));
		return type_struct_get(info, emt);

	default:
558
		abort();
559 560
	}
}
561

562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582
size_t
type_aggregate_size(struct arg_type_info *info)
{
	assert(info->type == ARGTYPE_STRUCT
	       || info->type == ARGTYPE_ARRAY);

	switch (info->type) {
		long ret;
	case ARGTYPE_ARRAY:
		if (expr_eval_constant(info->u.array_info.length, &ret) < 0)
			return (size_t)-1;
		return (size_t)ret;

	case ARGTYPE_STRUCT:
		return type_struct_size(info);

	default:
		abort();
	}
}

583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635
int
type_is_integral(enum arg_type type)
{
	switch (type) {
	case ARGTYPE_INT:
	case ARGTYPE_UINT:
	case ARGTYPE_LONG:
	case ARGTYPE_ULONG:
	case ARGTYPE_CHAR:
	case ARGTYPE_SHORT:
	case ARGTYPE_USHORT:
		return 1;

	case ARGTYPE_VOID:
	case ARGTYPE_FLOAT:
	case ARGTYPE_DOUBLE:
	case ARGTYPE_ARRAY:
	case ARGTYPE_STRUCT:
	case ARGTYPE_POINTER:
		return 0;
	}
	abort();
}

int
type_is_signed(enum arg_type type)
{
	assert(type_is_integral(type));

	switch (type) {
	case ARGTYPE_CHAR:
		return CHAR_MIN != 0;

	case ARGTYPE_SHORT:
	case ARGTYPE_INT:
	case ARGTYPE_LONG:
		return 1;

	case ARGTYPE_UINT:
	case ARGTYPE_ULONG:
	case ARGTYPE_USHORT:
		return 0;

	case ARGTYPE_VOID:
	case ARGTYPE_FLOAT:
	case ARGTYPE_DOUBLE:
	case ARGTYPE_ARRAY:
	case ARGTYPE_STRUCT:
	case ARGTYPE_POINTER:
		abort();
	}
	abort();
}
636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669

struct arg_type_info *
type_get_fp_equivalent(struct arg_type_info *info)
{
	/* Extract innermost structure.  Give up early if any
	 * component has more than one element.  */
	while (info->type == ARGTYPE_STRUCT) {
		if (type_struct_size(info) != 1)
			return NULL;
		info = type_element(info, 0);
	}

	switch (info->type) {
	case ARGTYPE_CHAR:
	case ARGTYPE_SHORT:
	case ARGTYPE_INT:
	case ARGTYPE_LONG:
	case ARGTYPE_UINT:
	case ARGTYPE_ULONG:
	case ARGTYPE_USHORT:
	case ARGTYPE_VOID:
	case ARGTYPE_ARRAY:
	case ARGTYPE_POINTER:
		return NULL;

	case ARGTYPE_FLOAT:
	case ARGTYPE_DOUBLE:
		return info;

	case ARGTYPE_STRUCT:
		abort();
	}
	abort();
}
670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705

struct arg_type_info *
type_get_hfa_type(struct arg_type_info *info, size_t *countp)
{
	assert(info != NULL);
	if (info->type != ARGTYPE_STRUCT
	    && info->type != ARGTYPE_ARRAY)
		return NULL;

	size_t n = type_aggregate_size(info);
	if (n == (size_t)-1)
		return NULL;

	struct arg_type_info *ret = NULL;
	*countp = 0;

	while (n-- > 0) {
		struct arg_type_info *emt = type_element(info, n);

		size_t emt_count = 1;
		if (emt->type == ARGTYPE_STRUCT || emt->type == ARGTYPE_ARRAY)
			emt = type_get_hfa_type(emt, &emt_count);
		if (emt == NULL)
			return NULL;
		if (ret == NULL) {
			if (emt->type != ARGTYPE_FLOAT
			    && emt->type != ARGTYPE_DOUBLE)
				return NULL;
			ret = emt;
		}
		if (emt->type != ret->type)
			return NULL;
		*countp += emt_count;
	}
	return ret;
}