File: printf.c

package info (click to toggle)
ltrace 0.7.3-6.1
  • links: PTS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 3,968 kB
  • sloc: ansic: 22,858; sh: 10,956; exp: 1,498; makefile: 375; cpp: 196; awk: 88; asm: 40; perl: 24
file content (365 lines) | stat: -rw-r--r-- 8,253 bytes parent folder | download | duplicates (3)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
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
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
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
136
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
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
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
259
260
261
262
263
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
355
356
357
358
359
360
361
362
363
364
365
/*
 * This file is part of ltrace.
 * Copyright (C) 2011,2012 Petr Machata, Red Hat Inc.
 * Copyright (C) 1998,2004,2007,2008,2009 Juan Cespedes
 * Copyright (C) 2006 Steve Fink
 * Copyright (C) 2006 Ian Wienand
 *
 * 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>

#include "printf.h"
#include "type.h"
#include "value.h"
#include "expr.h"
#include "zero.h"
#include "param.h"
#include "lens_default.h"

struct param_enum {
	struct value array;
	int percent;
	size_t *future_length;
	char *format;
	char const *ptr;
	char const *end;
};

static struct param_enum *
param_printf_init(struct value *cb_args, size_t nargs,
		  struct value_dict *arguments)
{
	assert(nargs == 1);

	/* We expect a char array pointer.  */
	if (cb_args->type->type != ARGTYPE_POINTER
	    || cb_args->type->u.ptr_info.info->type != ARGTYPE_ARRAY
	    || (cb_args->type->u.ptr_info.info->u.array_info.elt_type->type
		!= ARGTYPE_CHAR))
		return NULL;

	struct param_enum *self = malloc(sizeof(*self));
	if (self == NULL) {
	fail:
		free(self);
		return NULL;
	}

	if (value_init_deref(&self->array, cb_args) < 0)
		goto fail;

	assert(self->array.type->type == ARGTYPE_ARRAY);

	self->format = (char *)value_get_data(&self->array, arguments);
	if (self->format == NULL) {
		value_destroy(&self->array);
		goto fail;
	}

	size_t size = value_size(&self->array, arguments);
	if (size == (size_t)-1) {
		value_destroy(&self->array);
		goto fail;
	}

	self->percent = 0;
	self->ptr = self->format;
	self->end = self->format + size;
	self->future_length = NULL;
	return self;
}

static void
drop_future_length(struct param_enum *self)
{
	if (self->future_length != NULL) {
		free(self->future_length);
		self->future_length = NULL;
	}
}

static int
form_next_param(struct param_enum *self,
		enum arg_type format_type, enum arg_type elt_type,
		unsigned hlf, unsigned lng, char *len_buf, size_t len_buf_len,
		struct arg_type_info *infop)
{
	/* XXX note: Some types are wrong because we lack
	   ARGTYPE_LONGLONG, ARGTYPE_UCHAR and ARGTYPE_SCHAR.  */
	assert(lng <= 2);
	assert(hlf <= 2);
	static enum arg_type ints[] =
		{ ARGTYPE_CHAR, ARGTYPE_SHORT, ARGTYPE_INT,
		  ARGTYPE_LONG, ARGTYPE_ULONG };
	static enum arg_type uints[] =
		{ ARGTYPE_CHAR, ARGTYPE_USHORT, ARGTYPE_UINT,
		  ARGTYPE_ULONG, ARGTYPE_ULONG };

	struct arg_type_info *elt_info = NULL;
	if (format_type == ARGTYPE_ARRAY || format_type == ARGTYPE_POINTER)
		elt_info = type_get_simple(elt_type);
	else if (format_type == ARGTYPE_INT)
		format_type = ints[2 + lng - hlf];
	else if (format_type == ARGTYPE_UINT)
		format_type = uints[2 + lng - hlf];


	if (format_type == ARGTYPE_ARRAY) {
		struct arg_type_info *array = malloc(sizeof(*array));
		if (array == NULL)
			return -1;

		struct expr_node *node = NULL;
		int own_node;
		if (len_buf_len != 0
		    || self->future_length != NULL) {
			struct tmp {
				struct expr_node node;
				struct arg_type_info type;
			};
			struct tmp *len = malloc(sizeof(*len));
			if (len == NULL) {
			fail:
				free(len);
				free(array);
				return -1;
			}

			len->type = *type_get_simple(ARGTYPE_LONG);

			long l;
			if (self->future_length != NULL) {
				l = *self->future_length;
				drop_future_length(self);
			} else {
				l = atol(len_buf);
			}

			expr_init_const_word(&len->node, l, &len->type, 0);

			node = build_zero_w_arg(&len->node, 1);
			if (node == NULL)
				goto fail;
			own_node = 1;

		} else {
			node = expr_node_zero();
			own_node = 0;
		}
		assert(node != NULL);

		type_init_array(array, elt_info, 0, node, own_node);
		type_init_pointer(infop, array, 1);

	} else if (format_type == ARGTYPE_POINTER) {
		type_init_pointer(infop, elt_info, 0);

	} else {
		*infop = *type_get_simple(format_type);
	}

	return 0;
}

static int
param_printf_next(struct param_enum *self, struct arg_type_info *infop,
		  int *insert_stop)
{
	unsigned hlf = 0;
	unsigned lng = 0;
	enum arg_type format_type = ARGTYPE_VOID;
	enum arg_type elt_type = ARGTYPE_VOID;
	char len_buf[25] = {};
	size_t len_buf_len = 0;
	struct lens *lens = NULL;

	for (; self->ptr < self->end; ++self->ptr) {
		if (!self->percent) {
			if (*self->ptr == '%')
				self->percent = 1;
			continue;
		}

		switch (*self->ptr) {
		case '#': case ' ': case '-':
		case '+': case 'I': case '\'':
			/* These are only important for formatting,
			 * not for interpreting the type.  */
			continue;

		case '*':
			/* Length parameter given in the next
			 * argument.  */
			if (self->future_length == NULL)
				/* This should really be an assert,
				 * but we can't just fail on invalid
				 * format string.  */
				self->future_length
					= malloc(sizeof(*self->future_length));

			if (self->future_length != NULL) {
				++self->ptr;
				format_type = ARGTYPE_INT;
				break;
			}

		case '0':
		case '1': case '2': case '3':
		case '4': case '5': case '6':
		case '7': case '8': case '9':
			/* Field length likewise, but we need to parse
			 * this to attach the appropriate string
			 * length expression.  */
			if (len_buf_len < sizeof(len_buf) - 1)
				len_buf[len_buf_len++] = *self->ptr;
			continue;

		case 'h':
			if (hlf < 2)
				hlf++;
			continue;

		case 'l':
			if (lng < 2)
				lng++;
			continue;

		case 'q':
			lng = 2;
			continue;

		case 'L': /* long double */
			lng = 1;
			continue;

		case 'j': /* intmax_t */
			/*   XXX ABI should know */
			lng = 2;
			continue;

		case 't': /* ptrdiff_t */
		case 'Z': case 'z': /* size_t */
			lng = 1; /* XXX ABI should tell */
			continue;

		case 'd':
		case 'i':
			format_type = ARGTYPE_INT;
			self->percent = 0;
			break;

		case 'o':
			lens = &octal_lens;
			goto uint;

		case 'x': case 'X':
			lens = &hex_lens;
		case 'u':
		uint:
			format_type = ARGTYPE_UINT;
			self->percent = 0;
			break;

		case 'e': case 'E':
		case 'f': case 'F':
		case 'g': case 'G':
		case 'a': case 'A':
			format_type = ARGTYPE_DOUBLE;
			self->percent = 0;
			break;

		case 'C': /* like "lc" */
			if (lng == 0)
				lng++;
		case 'c':
			/* XXX "lc" means wchar_t string.  */
			format_type = ARGTYPE_CHAR;
			self->percent = 0;
			break;

		case 'S': /* like "ls" */
			if (lng == 0)
				lng++;
		case 's':
			format_type = ARGTYPE_ARRAY;
			/* XXX "ls" means wchar_t string.  */
			elt_type = ARGTYPE_CHAR;
			self->percent = 0;
			lens = &string_lens;
			break;

		case 'p':
		case 'n': /* int* where to store no. of printed chars.  */
			format_type = ARGTYPE_POINTER;
			elt_type = ARGTYPE_VOID;
			self->percent = 0;
			break;

		case 'm': /* (glibc) print argument of errno */
		case '%':
			lng = 0;
			hlf = 0;
			self->percent = 0;
			continue;

		default:
			continue;
		}

		/* If we got here, the type must have been set.  */
		assert(format_type != ARGTYPE_VOID);

		if (form_next_param(self, format_type, elt_type, hlf, lng,
				    len_buf, len_buf_len, infop) < 0)
			return -1;

		infop->lens = lens;
		infop->own_lens = 0;

		return 0;
	}

	*infop = *type_get_simple(ARGTYPE_VOID);
	return 0;
}

static enum param_status
param_printf_stop(struct param_enum *self, struct value *value)
{
	if (self->future_length != NULL
	    && value_extract_word(value, (long *)self->future_length, NULL) < 0)
		drop_future_length(self);

	return PPCB_CONT;
}

static void
param_printf_done(struct param_enum *context)
{
	value_destroy(&context->array);
	free(context);
}

void
param_pack_init_printf(struct param *param, struct expr_node *arg, int own_arg)
{
	param_init_pack(param, PARAM_PACK_VARARGS, arg, 1, own_arg,
			&param_printf_init, &param_printf_next,
			&param_printf_stop, &param_printf_done);
}