lens_default.c revision c00837c2928da53a3515b107399b742ea157e78a
1/*
2 * This file is part of ltrace.
3 * Copyright (C) 2011,2012,2013 Petr Machata, Red Hat Inc.
4 * Copyright (C) 1998,2004,2007,2008,2009 Juan Cespedes
5 * Copyright (C) 2006 Ian Wienand
6 * Copyright (C) 2006 Steve Fink
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
21 * 02110-1301 USA
22 */
23
24#include <ctype.h>
25#include <stdlib.h>
26#include <assert.h>
27#include <inttypes.h>
28#include <stdarg.h>
29#include <stdio.h>
30#include <string.h>
31
32#include "bits.h"
33#include "proc.h"
34#include "lens_default.h"
35#include "value.h"
36#include "expr.h"
37#include "type.h"
38#include "common.h"
39#include "zero.h"
40
41#define READER(NAME, TYPE)						\
42	static int							\
43	NAME(struct value *value, TYPE *ret, struct value_dict *arguments) \
44	{								\
45		union {							\
46			TYPE val;					\
47			unsigned char buf[0];				\
48		} u;							\
49		if (value_extract_buf(value, u.buf, arguments) < 0)	\
50			return -1;					\
51		*ret = u.val;						\
52		return 0;						\
53	}
54
55READER(read_float, float)
56READER(read_double, double)
57
58#undef READER
59
60#define HANDLE_WIDTH(BITS)						\
61	do {								\
62		long l;							\
63		if (value_extract_word(value, &l, arguments) < 0)	\
64			return -1;					\
65		int##BITS##_t i = l;					\
66		uint64_t v = (uint64_t)(uint##BITS##_t)i;		\
67		switch (format) {					\
68		case INT_FMT_unknown:					\
69			if (l < -10000 || l > 10000)			\
70		case INT_FMT_x:						\
71			return fprintf(stream, "%#"PRIx64, v);		\
72		case INT_FMT_i:						\
73		case INT_FMT_default:					\
74			return fprintf(stream, "%"PRIi##BITS, i);	\
75		case INT_FMT_u:						\
76			return fprintf(stream, "%"PRIu64, v);		\
77		case INT_FMT_o:						\
78			return fprintf(stream, "0%"PRIo64, v);		\
79		}							\
80	} while (0)
81
82enum int_fmt_t
83{
84	INT_FMT_i,
85	INT_FMT_u,
86	INT_FMT_o,
87	INT_FMT_x,
88	INT_FMT_unknown,
89	INT_FMT_default,
90};
91
92static int
93format_integer(FILE *stream, struct value *value, enum int_fmt_t format,
94	       struct value_dict *arguments)
95{
96	switch (type_sizeof(value->inferior, value->type)) {
97
98	case 1: HANDLE_WIDTH(8);
99	case 2: HANDLE_WIDTH(16);
100	case 4: HANDLE_WIDTH(32);
101	case 8: HANDLE_WIDTH(64);
102
103	default:
104		assert(!"unsupported integer width");
105		abort();
106
107	case -1:
108		return -1;
109	}
110}
111
112#undef HANDLE_WIDTH
113
114static int
115acc_fprintf(int *countp, FILE *stream, const char *format, ...)
116{
117	va_list pa;
118	va_start(pa, format);
119	int i = account_output(countp, vfprintf(stream, format, pa));
120	va_end(pa);
121
122	return i;
123}
124
125static int
126print_char(FILE *stream, int c)
127{
128	const char *fmt;
129	switch (c) {
130	case -1:
131		fmt = "EOF";
132		break;
133	case 0:
134		fmt = "\\0";
135		break;
136	case '\a':
137		fmt = "\\a";
138		break;
139	case '\b':
140		fmt = "\\b";
141		break;
142	case '\t':
143		fmt = "\\t";
144		break;
145	case '\n':
146		fmt = "\\n";
147		break;
148	case '\v':
149		fmt = "\\v";
150		break;
151	case '\f':
152		fmt = "\\f";
153		break;
154	case '\r':
155		fmt = "\\r";
156		break;
157	case '\\':
158		fmt = "\\\\";
159		break;
160	default:
161		if (isprint(c) || c == ' ')
162			fmt = "%c";
163		else
164			fmt = "\\%03o";
165	}
166
167	return fprintf(stream, fmt, c);
168}
169
170static int
171format_char(FILE *stream, struct value *value, struct value_dict *arguments)
172{
173	long lc;
174	if (value_extract_word(value, &lc, arguments) < 0)
175		return -1;
176	return print_char(stream, (int) lc);
177}
178
179static int
180format_naked(FILE *stream, struct value *value,
181	     struct value_dict *arguments,
182	     int (*what)(FILE *, struct value *, struct value_dict *))
183{
184	int written = 0;
185	if (acc_fprintf(&written, stream, "'") < 0
186	    || account_output(&written,
187			      what(stream, value, arguments)) < 0
188	    || acc_fprintf(&written, stream, "'") < 0)
189		return -1;
190
191	return written;
192}
193
194static int
195format_double(FILE *stream, double value, enum int_fmt_t format)
196{
197	if (format == INT_FMT_x)
198		return fprintf(stream, "%a", value);
199	else
200		return fprintf(stream, "%f", value);
201}
202
203static int
204format_floating(FILE *stream, struct value *value, struct value_dict *arguments,
205		enum int_fmt_t format)
206{
207	switch (value->type->type) {
208		float f;
209		double d;
210	case ARGTYPE_FLOAT:
211		if (read_float(value, &f, arguments) < 0)
212			return -1;
213		return format_double(stream, f, format);
214	case ARGTYPE_DOUBLE:
215		if (read_double(value, &d, arguments) < 0)
216			return -1;
217		return format_double(stream, d, format);
218	default:
219		abort();
220	}
221}
222
223struct format_argument_data
224{
225	struct value *value;
226	struct value_dict *arguments;
227};
228
229static int
230format_argument_cb(FILE *stream, void *ptr)
231{
232	struct format_argument_data *data = ptr;
233	return format_argument(stream, data->value, data->arguments);
234}
235
236static int
237format_struct(FILE *stream, struct value *value, struct value_dict *arguments)
238{
239	int written = 0;
240	if (acc_fprintf(&written, stream, "{ ") < 0)
241		return -1;
242
243	int need_delim = 0;
244	size_t i;
245	for (i = 0; i < type_struct_size(value->type); ++i) {
246		struct value element;
247		if (value_init_element(&element, value, i) < 0)
248			return -1;
249
250		struct format_argument_data data = { &element, arguments };
251		int o = delim_output(stream, &need_delim,
252				     format_argument_cb, &data);
253		value_destroy(&element);
254		if (o < 0)
255			return -1;
256
257		written += o;
258	}
259	if (acc_fprintf(&written, stream, " }") < 0)
260		return -1;
261	return written;
262}
263
264static const char null_message[] = "nil";
265int
266format_pointer(FILE *stream, struct value *value, struct value_dict *arguments)
267{
268	if (value_is_zero(value, arguments))
269		return fprintf(stream, null_message);
270
271	/* The following is for detecting recursion.  We keep track of
272	 * the values that were already displayed.  Each time a
273	 * pointer should be dereferenced, we compare its value to the
274	 * value of each of the pointers dereferenced so far.  If one
275	 * of them matches, instead of recursing, we just printf which
276	 * superstructure this pointer recurses to.  */
277	static struct vect pointers = {};
278	if (pointers.elt_size == 0)
279		VECT_INIT(&pointers, struct value *);
280
281	/* Trim number of expanded structures of the same type.  Even
282	 * for non-recursive structure, we don't want to expand all of
283	 * it if it's huge.  */
284	size_t i;
285	size_t len = vect_size(&pointers);
286	assert(value->type->type == ARGTYPE_POINTER);
287	struct arg_type_info *pointee = value->type->u.ptr_info.info;
288	if (pointee->type == ARGTYPE_STRUCT) {
289		size_t depth = 0;
290		for (i = 0; i < len; ++i) {
291			struct value *old
292				= *VECT_ELEMENT(&pointers, struct value *, i);
293			assert(old->type->type == ARGTYPE_POINTER);
294			struct arg_type_info *old_pointee
295				= old->type->u.ptr_info.info;
296			if (old_pointee == pointee)
297				depth++;
298		}
299		if (depth >= options.arraylen)
300			return fprintf(stream, "...");
301	}
302
303	for (i = len; i-- > 0 ;) {
304		struct value **old = VECT_ELEMENT(&pointers, struct value *, i);
305		int rc = value_equal(value, *old, arguments);
306		if (rc < 0)
307			return -1;
308		if (rc > 0) {
309			size_t reclevel = len - i - 1;
310			char buf[reclevel + 1];
311			memset(buf, '^', sizeof buf);
312			buf[reclevel] = 0;
313			return fprintf(stream, "recurse%s", buf);
314		}
315	}
316
317	/* OK, not a recursion.  Remember this value for tracking.  */
318	if (VECT_PUSHBACK(&pointers, &value) < 0)
319		return -1;
320
321	struct value element;
322	int o;
323	if (value_init_deref(&element, value) < 0) {
324		o = -1;
325		goto done;
326	}
327	o = format_argument(stream, &element, arguments);
328	value_destroy(&element);
329
330done:
331	VECT_POPBACK(&pointers, struct value *, NULL, NULL);
332	return o;
333}
334
335/*
336 * LENGTH is an expression whose evaluation will yield the actual
337 *    length of the array.
338 *
339 * MAXLEN is the actual maximum length that we care about
340 *
341 * BEFORE if LENGTH>MAXLEN, we display ellipsis.  We display it before
342 *    the closing parenthesis if BEFORE, otherwise after it.
343 *
344 * OPEN, CLOSE, DELIM are opening and closing parenthesis and element
345 *    delimiter.
346 */
347static int
348format_array(FILE *stream, struct value *value, struct value_dict *arguments,
349	     struct expr_node *length, size_t maxlen, int before,
350	     const char *open, const char *close, const char *delim)
351{
352	/* We need "long" to be long enough to cover the whole address
353	 * space.  */
354	(void)sizeof(char[1 - 2*(sizeof(long) < sizeof(void *))]);
355	long l;
356	if (expr_eval_word(length, value, arguments, &l) < 0)
357		return -1;
358	size_t len = (size_t)l;
359
360	int written = 0;
361	if (acc_fprintf(&written, stream, "%s", open) < 0)
362		return -1;
363
364	size_t i;
365	for (i = 0; i < len && i <= maxlen; ++i) {
366		if (i == maxlen) {
367			if (before && acc_fprintf(&written, stream, "...") < 0)
368				return -1;
369			break;
370		}
371
372		if (i > 0 && acc_fprintf(&written, stream, "%s", delim) < 0)
373			return -1;
374
375		struct value element;
376		if (value_init_element(&element, value, i) < 0)
377			return -1;
378		int o = format_argument(stream, &element, arguments);
379		value_destroy(&element);
380		if (o < 0)
381			return -1;
382		written += o;
383	}
384	if (acc_fprintf(&written, stream, "%s", close) < 0)
385		return -1;
386	if (i == maxlen && !before && acc_fprintf(&written, stream, "...") < 0)
387		return -1;
388
389	return written;
390}
391
392static int
393toplevel_format_lens(struct lens *lens, FILE *stream,
394		     struct value *value, struct value_dict *arguments,
395		     enum int_fmt_t int_fmt)
396{
397	switch (value->type->type) {
398	case ARGTYPE_VOID:
399		return fprintf(stream, "<void>");
400
401	case ARGTYPE_SHORT:
402	case ARGTYPE_INT:
403	case ARGTYPE_LONG:
404		return format_integer(stream, value, int_fmt, arguments);
405
406	case ARGTYPE_USHORT:
407	case ARGTYPE_UINT:
408	case ARGTYPE_ULONG:
409		if (int_fmt == INT_FMT_i || int_fmt == INT_FMT_default)
410			int_fmt = INT_FMT_u;
411		return format_integer(stream, value, int_fmt, arguments);
412
413	case ARGTYPE_CHAR:
414		if (int_fmt == INT_FMT_default)
415			return format_naked(stream, value, arguments,
416					    &format_char);
417		return format_integer(stream, value, int_fmt, arguments);
418
419	case ARGTYPE_FLOAT:
420	case ARGTYPE_DOUBLE:
421		return format_floating(stream, value, arguments, int_fmt);
422
423	case ARGTYPE_STRUCT:
424		return format_struct(stream, value, arguments);
425
426	case ARGTYPE_POINTER:
427		if (value_is_zero(value, arguments))
428			return fprintf(stream, null_message);
429		if (value->type->u.array_info.elt_type->type != ARGTYPE_VOID)
430			return format_pointer(stream, value, arguments);
431		return format_integer(stream, value, INT_FMT_x, arguments);
432
433	case ARGTYPE_ARRAY:
434		return format_array(stream, value, arguments,
435				    value->type->u.array_info.length,
436				    options.arraylen, 1, "[ ", " ]", ", ");
437	}
438	abort();
439}
440
441static int
442default_lens_format_cb(struct lens *lens, FILE *stream,
443		       struct value *value, struct value_dict *arguments)
444{
445	return toplevel_format_lens(lens, stream, value, arguments,
446				    INT_FMT_default);
447}
448
449struct lens default_lens = {
450	.format_cb = default_lens_format_cb,
451};
452
453
454static int
455blind_lens_format_cb(struct lens *lens, FILE *stream,
456		     struct value *value, struct value_dict *arguments)
457{
458	return 0;
459}
460
461struct lens blind_lens = {
462	.format_cb = blind_lens_format_cb,
463};
464
465
466static int
467octal_lens_format_cb(struct lens *lens, FILE *stream,
468		     struct value *value, struct value_dict *arguments)
469{
470	return toplevel_format_lens(lens, stream, value, arguments, INT_FMT_o);
471}
472
473struct lens octal_lens = {
474	.format_cb = octal_lens_format_cb,
475};
476
477
478static int
479hex_lens_format_cb(struct lens *lens, FILE *stream,
480		   struct value *value, struct value_dict *arguments)
481{
482	return toplevel_format_lens(lens, stream, value, arguments, INT_FMT_x);
483}
484
485struct lens hex_lens = {
486	.format_cb = hex_lens_format_cb,
487};
488
489
490static int
491dec_lens_format_cb(struct lens *lens, FILE *stream,
492		   struct value *value, struct value_dict *arguments)
493{
494	return toplevel_format_lens(lens, stream, value, arguments, INT_FMT_u);
495}
496
497struct lens dec_lens = {
498	.format_cb = dec_lens_format_cb,
499};
500
501
502static int
503guess_lens_format_cb(struct lens *lens, FILE *stream,
504		     struct value *value, struct value_dict *arguments)
505{
506	return toplevel_format_lens(lens, stream, value, arguments,
507				    INT_FMT_unknown);
508}
509
510struct lens guess_lens = {
511	.format_cb = guess_lens_format_cb,
512};
513
514
515static int
516bool_lens_format_cb(struct lens *lens, FILE *stream,
517		    struct value *value, struct value_dict *arguments)
518{
519	switch (value->type->type) {
520	case ARGTYPE_VOID:
521	case ARGTYPE_FLOAT:
522	case ARGTYPE_DOUBLE:
523	case ARGTYPE_STRUCT:
524	case ARGTYPE_POINTER:
525	case ARGTYPE_ARRAY:
526		return toplevel_format_lens(lens, stream, value,
527					    arguments, INT_FMT_default);
528
529		int zero;
530	case ARGTYPE_SHORT:
531	case ARGTYPE_INT:
532	case ARGTYPE_LONG:
533	case ARGTYPE_USHORT:
534	case ARGTYPE_UINT:
535	case ARGTYPE_ULONG:
536	case ARGTYPE_CHAR:
537		if ((zero = value_is_zero(value, arguments)) < 0)
538			return -1;
539		if (zero)
540			return fprintf(stream, "false");
541		else
542			return fprintf(stream, "true");
543	}
544	abort();
545}
546
547struct lens bool_lens = {
548	.format_cb = bool_lens_format_cb,
549};
550
551static int
552redispatch_as_array(struct lens *lens, FILE *stream,
553		    struct value *value, struct value_dict *arguments,
554		    int (*cb)(struct lens *, FILE *,
555			      struct value *, struct value_dict *))
556{
557	struct arg_type_info info[2];
558	type_init_array(&info[1], value->type->u.ptr_info.info, 0,
559			expr_node_zero(), 0);
560	type_init_pointer(&info[0], &info[1], 0);
561	info->lens = lens;
562	info->own_lens = 0;
563	struct value tmp;
564	if (value_clone(&tmp, value) < 0)
565		return -1;
566	value_set_type(&tmp, info, 0);
567	int ret = cb(lens, stream, &tmp, arguments);
568	type_destroy(&info[0]);
569	type_destroy(&info[1]);
570	value_destroy(&tmp);
571	return ret;
572}
573
574static int
575format_wchar(FILE *stream, struct value *value, struct value_dict *arguments)
576{
577	long l;
578	if (value_extract_word(value, &l, arguments) < 0)
579		return -1;
580	wchar_t wc = (wchar_t) l;
581	char buf[MB_CUR_MAX + 1];
582
583	int c = wctomb(buf, wc);
584	if (c < 0)
585		return -1;
586	if (c == 1)
587		return print_char(stream, buf[0]);
588
589	buf[c] = 0;
590	return fprintf(stream, "%s", buf) >= 0 ? 1 : -1;
591}
592
593static int
594string_lens_format_cb(struct lens *lens, FILE *stream,
595		      struct value *value, struct value_dict *arguments)
596{
597	switch (value->type->type) {
598	case ARGTYPE_POINTER:
599		/* This should really be written as either "string",
600		 * or, if lens, then string(array(char, zero)*).  But
601		 * I suspect people are so used to the char * C idiom,
602		 * that string(char *) might actually turn up.  So
603		 * let's just support it.  */
604		switch ((int) value->type->u.ptr_info.info->type)
605		case ARGTYPE_CHAR:
606		case ARGTYPE_SHORT:
607		case ARGTYPE_USHORT:
608		case ARGTYPE_INT:
609		case ARGTYPE_UINT:
610		case ARGTYPE_LONG:
611		case ARGTYPE_ULONG:
612			return redispatch_as_array(lens, stream, value,
613						   arguments,
614						   &string_lens_format_cb);
615
616		/* Otherwise dispatch to whatever the default for the
617		 * pointee is--most likely this will again be us.  */
618		/* Fall through.  */
619	case ARGTYPE_VOID:
620	case ARGTYPE_FLOAT:
621	case ARGTYPE_DOUBLE:
622	case ARGTYPE_STRUCT:
623		return toplevel_format_lens(lens, stream, value,
624					    arguments, INT_FMT_default);
625
626	case ARGTYPE_SHORT:
627	case ARGTYPE_INT:
628	case ARGTYPE_LONG:
629	case ARGTYPE_USHORT:
630	case ARGTYPE_UINT:
631	case ARGTYPE_ULONG:
632		if (value->parent != NULL && value->type->lens == NULL)
633			return format_wchar(stream, value, arguments);
634		else
635			return format_naked(stream, value, arguments,
636					    &format_wchar);
637
638	case ARGTYPE_CHAR:
639		return format_char(stream, value, arguments);
640
641	case ARGTYPE_ARRAY:
642		return format_array(stream, value, arguments,
643				    value->type->u.array_info.length,
644				    options.strlen, 0, "\"", "\"", "");
645	}
646	abort();
647}
648
649struct lens string_lens = {
650	.format_cb = string_lens_format_cb,
651};
652
653static int
654out_bits(FILE *stream, size_t low, size_t high)
655{
656	if (low == high)
657		return fprintf(stream, "%zd", low);
658	else
659		return fprintf(stream, "%zd-%zd", low, high);
660}
661
662static int
663bitvect_lens_format_cb(struct lens *lens, FILE *stream,
664		       struct value *value, struct value_dict *arguments)
665{
666	unsigned char *data = value_get_data(value, arguments);
667	if (data == NULL)
668		return -1;
669	size_t sz = type_sizeof(value->inferior, value->type);
670	if (sz == (size_t)-1)
671		return -1;
672
673	size_t i;
674	unsigned char buf[sz];
675	switch ((int)value->type->type) {
676		union bitvect_integral_64
677		{
678			uint8_t u8;
679			uint16_t u16;
680			uint32_t u32;
681			uint64_t u64;
682			unsigned char buf[0];
683		} bv;
684
685	case ARGTYPE_POINTER:
686		return format_pointer(stream, value, arguments);
687
688	case ARGTYPE_STRUCT:
689	case ARGTYPE_ARRAY:
690		break;
691
692	default:
693		assert(sz <= sizeof(bv));
694		memmove(bv.buf, data, sz);
695
696		if (sz == 1)
697			bv.u64 = bv.u8;
698		else if (sz == 2)
699			bv.u64 = bv.u16;
700		else if (sz == 4)
701			bv.u64 = bv.u32;
702
703		for (i = 0; i < sz; ++i) {
704			buf[i] = bv.u64 & 0xff;
705			bv.u64 >>= 8;
706		}
707		data = buf;
708	}
709
710	size_t bits = 0;
711	for (i = 0; i < sz; ++i)
712		bits += bitcount(data[i]);
713
714	/* If there's more 1's than 0's, show inverse.  */
715	unsigned neg = bits > sz * 4 ? 0xff : 0x00;
716
717	int o = 0;
718	if (acc_fprintf(&o, stream, "%s<", &"~"[neg == 0x00]) < 0)
719		return -1;
720
721	size_t bitno = 0;
722	ssize_t low = -1;
723	for (i = 0; i < sz; ++i) {
724		unsigned char m;
725		unsigned char d = data[i] ^ neg;
726		for (m = 0x01; m != 0; m <<= 1) {
727			int bit = !!(m & d);
728			if (low < 0) {
729				if (bit) {
730					if (low == -2
731					    && acc_fprintf(&o, stream, ",") < 0)
732						return -1;
733					low = bitno;
734				}
735			} else if (!bit) {
736				if (account_output(&o, out_bits(stream, low,
737								bitno-1)) < 0)
738					return -1;
739				low = -2;
740			}
741			bitno++;
742		}
743	}
744	if (low >= 0 && account_output(&o, out_bits(stream, low, bitno-1)) < 0)
745		return -1;
746
747	if (fputc('>', stream) < 0)
748		return -1;
749	o += 1;
750
751	return o;
752}
753
754struct lens bitvect_lens = {
755	.format_cb = bitvect_lens_format_cb,
756};
757