summaryrefslogtreecommitdiff
path: root/coreutils/printf.c
blob: 0e818354fed21e8d30c35c9d3aa7111c9c508079 (plain)
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
/* vi: set sw=4 ts=4: */
/* printf - format and print data

   Copyright 1999 Dave Cinege
   Portions copyright (C) 1990-1996 Free Software Foundation, Inc.

   Licensed under GPL v2 or later, see file LICENSE in this tarball for details.
*/

/* Usage: printf format [argument...]

   A front end to the printf function that lets it be used from the shell.

   Backslash escapes:

   \" = double quote
   \\ = backslash
   \a = alert (bell)
   \b = backspace
   \c = produce no further output
   \f = form feed
   \n = new line
   \r = carriage return
   \t = horizontal tab
   \v = vertical tab
   \0ooo = octal number (ooo is 0 to 3 digits)
   \xhhh = hexadecimal number (hhh is 1 to 3 digits)

   Additional directive:

   %b = print an argument string, interpreting backslash escapes

   The 'format' argument is re-used as many times as necessary
   to convert all of the given arguments.

   David MacKenzie <djm@gnu.ai.mit.edu> */


//   19990508 Busy Boxed! Dave Cinege

#include "busybox.h"

static int print_formatted(char *format, int argc, char **argv);
static void print_direc(char *start, size_t length,
			int field_width, int precision, char *argument);

typedef void (*converter)(char *arg, void *result);

static void multiconvert(char *arg, void *result, converter convert)
{
	char s[16];
	if (*arg == '"' || *arg == '\'') {
		sprintf(s, "%d", (unsigned char)arg[1]);
		arg = s;
	}
	convert(arg, result);
	if (errno) /* Huh, looks strange... bug? */
		fputs(arg, stderr);
}

static void conv_strtoul(char *arg, void *result)
{
	*(unsigned long*)result = bb_strtoul(arg, NULL, 10);
}
static void conv_strtol(char *arg, void *result)
{
	*(long*)result = bb_strtol(arg, NULL, 10);
}
static void conv_strtod(char *arg, void *result)
{
	char *end;
	/* Well, this one allows leading whitespace... so what */
	/* What I like much less is that "-" is accepted too! :( */
	*(double*)result = strtod(arg, &end);
	if (end[0]) errno = ERANGE;
}

static unsigned long my_xstrtoul(char *arg)
{
	unsigned long result;
	multiconvert(arg, &result, conv_strtoul);
	return result;
}

static long my_xstrtol(char *arg)
{
	long result;
	multiconvert(arg, &result, conv_strtol);
	return result;
}

static double my_xstrtod(char *arg)
{
	double result;
	multiconvert(arg, &result, conv_strtod);
	return result;
}

static void print_esc_string(char *str)
{
	for (; *str; str++) {
		if (*str == '\\') {
			str++;
			putchar(bb_process_escape_sequence((const char **)&str));
		} else {
			putchar(*str);
		}

	}
}

int printf_main(int argc, char **argv)
{
	char *format;
	int args_used;

	if (argc <= 1 || argv[1][0] == '-') {
		bb_show_usage();
	}

	format = argv[1];
	argc -= 2;
	argv += 2;

	do {
		args_used = print_formatted(format, argc, argv);
		argc -= args_used;
		argv += args_used;
	}
	while (args_used > 0 && argc > 0);

/*	if (argc > 0)
		fprintf(stderr, "excess args ignored");
*/

	return EXIT_SUCCESS;
}

/* Print the text in FORMAT, using ARGV (with ARGC elements) for
   arguments to any '%' directives.
   Return the number of elements of ARGV used.  */

static int print_formatted(char *format, int argc, char **argv)
{
	int save_argc = argc;		/* Preserve original value.  */
	char *f;					/* Pointer into 'format'.  */
	char *direc_start;			/* Start of % directive.  */
	size_t direc_length;		/* Length of % directive.  */
	int field_width;			/* Arg to first '*', or -1 if none.  */
	int precision;				/* Arg to second '*', or -1 if none.  */

	for (f = format; *f; ++f) {
		switch (*f) {
		case '%':
			direc_start = f++;
			direc_length = 1;
			field_width = precision = -1;
			if (*f == '%') {
				putchar('%');
				break;
			}
			if (*f == 'b') {
				if (argc > 0) {
					print_esc_string(*argv);
					++argv;
					--argc;
				}
				break;
			}
			if (strchr("-+ #", *f)) {
				++f;
				++direc_length;
			}
			if (*f == '*') {
				++f;
				++direc_length;
				if (argc > 0) {
					field_width = my_xstrtoul(*argv);
					++argv;
					--argc;
				} else
					field_width = 0;
			} else
				while (isdigit(*f)) {
					++f;
					++direc_length;
				}
			if (*f == '.') {
				++f;
				++direc_length;
				if (*f == '*') {
					++f;
					++direc_length;
					if (argc > 0) {
						precision = my_xstrtoul(*argv);
						++argv;
						--argc;
					} else
						precision = 0;
				} else
					while (isdigit(*f)) {
						++f;
						++direc_length;
					}
			}
			if (*f == 'l' || *f == 'L' || *f == 'h') {
				++f;
				++direc_length;
			}
			/*
			if (!strchr ("diouxXfeEgGcs", *f))
			fprintf(stderr, "%%%c: invalid directive", *f);
			*/
			++direc_length;
			if (argc > 0) {
				print_direc(direc_start, direc_length, field_width,
							precision, *argv);
				++argv;
				--argc;
			} else
				print_direc(direc_start, direc_length, field_width,
							precision, "");
			break;

		case '\\':
			if (*++f == 'c')
				exit(0);
			putchar(bb_process_escape_sequence((const char **)&f));
			f--;
			break;

		default:
			putchar(*f);
		}
	}

	return save_argc - argc;
}

static void
print_direc(char *start, size_t length, int field_width, int precision,
			char *argument)
{
	char *p;		/* Null-terminated copy of % directive. */

	p = xmalloc((unsigned) (length + 1));
	strncpy(p, start, length);
	p[length] = 0;

	switch (p[length - 1]) {
	case 'd':
	case 'i':
		if (field_width < 0) {
			if (precision < 0)
				printf(p, my_xstrtol(argument));
			else
				printf(p, precision, my_xstrtol(argument));
		} else {
			if (precision < 0)
				printf(p, field_width, my_xstrtol(argument));
			else
				printf(p, field_width, precision, my_xstrtol(argument));
		}
		break;

	case 'o':
	case 'u':
	case 'x':
	case 'X':
		if (field_width < 0) {
			if (precision < 0)
				printf(p, my_xstrtoul(argument));
			else
				printf(p, precision, my_xstrtoul(argument));
		} else {
			if (precision < 0)
				printf(p, field_width, my_xstrtoul(argument));
			else
				printf(p, field_width, precision, my_xstrtoul(argument));
		}
		break;

	case 'f':
	case 'e':
	case 'E':
	case 'g':
	case 'G':
		if (field_width < 0) {
			if (precision < 0)
				printf(p, my_xstrtod(argument));
			else
				printf(p, precision, my_xstrtod(argument));
		} else {
			if (precision < 0)
				printf(p, field_width, my_xstrtod(argument));
			else
				printf(p, field_width, precision, my_xstrtod(argument));
		}
		break;

	case 'c':
		printf(p, *argument);
		break;

	case 's':
		if (field_width < 0) {
			if (precision < 0)
				printf(p, argument);
			else
				printf(p, precision, argument);
		} else {
			if (precision < 0)
				printf(p, field_width, argument);
			else
				printf(p, field_width, precision, argument);
		}
		break;
	}

	free(p);
}