busybox/coreutils/printf.c

/* 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 "libbb.h"

/* A note on bad input: neither bash 3.2 nor coreutils 6.10 stop on it.
 * They report it:
 *  bash: printf: XXX: invalid number
 *  printf: XXX: expected a numeric value
 *  bash: printf: 123XXX: invalid number
 *  printf: 123XXX: value not completely converted
 * but then they use 0 (or partially converted numeric prefix) as a value
 * and continue. They exit with 1 in this case.
 * Both accept insane field width/precision (e.g. %9999999999.9999999999d).
 * Both print error message and assume 0 if %*.*f width/precision is "bad"
 *  (but negative numbers are not "bad").
 * Both accept negative numbers for %u specifier.
 *
 * We try to be compatible. We are not compatible here:
 * - we do not accept -NUM for %u
 * - exit code is 0 even if "invalid number" was seen (FIXME)
 * See "if (errno)" checks in the code below.
 */

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

static int multiconvert(const char *arg, void *result, converter convert)
{
	if (*arg == '"' || *arg == '\'') {
		arg = utoa((unsigned char)arg[1]);
	}
	errno = 0;
	convert(arg, result);
	if (errno) {
		bb_error_msg("%s: invalid number", arg);
		return 1;
	}
	return 0;
}

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

/* Callers should check errno to detect errors */
static unsigned long my_xstrtoul(const char *arg)
{
	unsigned long result;
	if (multiconvert(arg, &result, conv_strtoul))
		result = 0;
	return result;
}
static long my_xstrtol(const char *arg)
{
	long result;
	if (multiconvert(arg, &result, conv_strtol))
		result = 0;
	return result;
}
static double my_xstrtod(const char *arg)
{
	double result;
	multiconvert(arg, &result, conv_strtod);
	return result;
}

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

static void print_direc(char *format, unsigned fmt_length,
		int field_width, int precision,
		const char *argument)
{
	long lv;
	double dv;
	char saved;
	char *have_prec, *have_width;

	saved = format[fmt_length];
	format[fmt_length] = '\0';

	have_prec = strstr(format, ".*");
	have_width = strchr(format, '*');
	if (have_width - 1 == have_prec)
		have_width = NULL;

	switch (format[fmt_length - 1]) {
	case 'c':
		printf(format, *argument);
		break;
	case 'd':
	case 'i':
		lv = my_xstrtol(argument);
 print_long:
		/* if (errno) return; - see comment at the top */
		if (!have_width) {
			if (!have_prec)
				printf(format, lv);
			else
				printf(format, precision, lv);
		} else {
			if (!have_prec)
				printf(format, field_width, lv);
			else
				printf(format, field_width, precision, lv);
		}
		break;
	case 'o':
	case 'u':
	case 'x':
	case 'X':
		lv = my_xstrtoul(argument);
		/* cheat: unsigned long and long have same width, so... */
		goto print_long;
	case 's':
		/* Are char* and long the same? (true for most arches) */
		if (sizeof(argument) == sizeof(lv)) {
			lv = (long)(ptrdiff_t)argument;
			goto print_long;
		} else { /* Hope compiler will optimize it out */
			if (!have_width) {
				if (!have_prec)
					printf(format, argument);
				else
					printf(format, precision, argument);
			} else {
				if (!have_prec)
					printf(format, field_width, argument);
				else
					printf(format, field_width, precision, argument);
			}
			break;
		}
	case 'f':
	case 'e':
	case 'E':
	case 'g':
	case 'G':
		dv = my_xstrtod(argument);
		/* if (errno) return; */
		if (!have_width) {
			if (!have_prec)
				printf(format, dv);
			else
				printf(format, precision, dv);
		} else {
			if (!have_prec)
				printf(format, field_width, dv);
			else
				printf(format, field_width, precision, dv);
		}
		break;
	} /* switch */

	format[fmt_length] = saved;
}

/* Handle params for "%*.*f". Negative numbers are ok (compat). */
static int get_width_prec(const char *str)
{
	int v = bb_strtoi(str, NULL, 10);
	if (errno) {
		bb_error_msg("%s: invalid number", str);
		v = 0;
	}
	return v;
}

/* Print the text in FORMAT, using ARGV for arguments to any '%' directives.
   Return advanced ARGV.  */
static char **print_formatted(char *f, char **argv)
{
	char *direc_start;      /* Start of % directive.  */
	unsigned direc_length;  /* Length of % directive.  */
	int field_width;        /* Arg to first '*' */
	int precision;          /* Arg to second '*' */
	char **saved_argv = argv;

	for (; *f; ++f) {
		switch (*f) {
		case '%':
			direc_start = f++;
			direc_length = 1;
			field_width = precision = 0;
			if (*f == '%') {
				bb_putchar('%');
				break;
			}
			if (*f == 'b') {
				if (*argv) {
					print_esc_string(*argv);
					++argv;
				}
				break;
			}
			if (strchr("-+ #", *f)) {
				++f;
				++direc_length;
			}
			if (*f == '*') {
				++f;
				++direc_length;
				if (*argv)
					field_width = get_width_prec(*argv++);
			} else {
				while (isdigit(*f)) {
					++f;
					++direc_length;
				}
			}
			if (*f == '.') {
				++f;
				++direc_length;
				if (*f == '*') {
					++f;
					++direc_length;
					if (*argv)
						precision = get_width_prec(*argv++);
				} else {
					while (isdigit(*f)) {
						++f;
						++direc_length;
					}
				}
			}
			/* Remove size modifiers - "%Ld" would try to printf
			 * long long, we pass long, and it spews garbage */
			if ((*f | 0x20) == 'l' || *f == 'h' || *f == 'z') {
				overlapping_strcpy(f, f + 1);
			}
//FIXME: actually, the same happens with bare "%d":
//it printfs an int, but we pass long!
//What saves us is that on most arches stack slot
//is pointer-sized -> long-sized -> ints are promoted to longs
// for variadic functions -> printf("%d", int_v) is in reality
// indistinqushable from printf("%d", long_v) ->
// since printf("%d", int_v) works, printf("%d", long_v) has to work.
//But "clean" solution would be to add "l" to d,i,o,x,X.
//Probably makes sense to go all the way to "ll" then.
//Coreutils support long long-sized arguments.

			/* needed - try "printf %" without it */
			if (!strchr("diouxXfeEgGcs", *f)) {
				bb_error_msg("%s: invalid format", direc_start);
				/* causes main() to exit with error */
				return saved_argv - 1;
			}
			++direc_length;
			if (*argv) {
				print_direc(direc_start, direc_length, field_width,
							precision, *argv);
				++argv;
			} else {
				print_direc(direc_start, direc_length, field_width,
							precision, "");
			}
			/* if (errno) return saved_argv - 1; */
			break;
		case '\\':
			if (*++f == 'c') {
				return saved_argv; /* causes main() to exit */
			}
			bb_putchar(bb_process_escape_sequence((const char **)&f));
			f--;
			break;
		default:
			bb_putchar(*f);
		}
	}

	return argv;
}

int printf_main(int argc UNUSED_PARAM, char **argv)
{
	char *format;
	char **argv2;

	/* We must check that stdout is not closed.
	 * The reason for this is highly non-obvious.
	 * printf_main is used from shell.
	 * Shell must correctly handle 'printf "%s" foo'
	 * if stdout is closed. With stdio, output gets shoveled into
	 * stdout buffer, and even fflush cannot clear it out. It seems that
	 * even if libc receives EBADF on write attempts, it feels determined
	 * to output data no matter what. So it will try later,
	 * and possibly will clobber future output. Not good. */
// TODO: check fcntl() & O_ACCMODE == O_WRONLY or O_RDWR?
	if (fcntl(1, F_GETFL) == -1)
		return 1; /* match coreutils 6.10 (sans error msg to stderr) */
	//if (dup2(1, 1) != 1) - old way
	//	return 1;

	/* bash builtin errors out on "printf '-%s-\n' foo",
	 * coreutils-6.9 works. Both work with "printf -- '-%s-\n' foo".
	 * We will mimic coreutils. */
	if (argv[1] && argv[1][0] == '-' && argv[1][1] == '-' && !argv[1][2])
		argv++;
	if (!argv[1]) {
		if (ENABLE_ASH_BUILTIN_PRINTF
		 && applet_name[0] != 'p'
		) {
			bb_error_msg("usage: printf FORMAT [ARGUMENT...]");
			return 2; /* bash compat */
		}
		bb_show_usage();
	}

	format = argv[1];
	argv2 = argv + 2;

	do {
		argv = argv2;
		argv2 = print_formatted(format, argv);
	} while (argv2 > argv && *argv2);

	/* coreutils compat (bash doesn't do this):
	if (*argv)
		fprintf(stderr, "excess args ignored");
	*/

	return (argv2 < argv); /* if true, print_formatted errored out */
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/* printf - format and print data
3
4			Copyright 1999 Dave Cinege
5			Portions copyright (C) 1990-1996 Free Software Foundation, Inc.
6
7			Licensed under GPL v2 or later, see file LICENSE in this tarball for details.
8			*/
9
10			/* Usage: printf format [argument...]
11
12			A front end to the printf function that lets it be used from the shell.
13
14			Backslash escapes:
15
16			\" = double quote
17			\\ = backslash
18			\a = alert (bell)
19			\b = backspace
20			\c = produce no further output
21			\f = form feed
22			\n = new line
23			\r = carriage return
24			\t = horizontal tab
25			\v = vertical tab
26			\0ooo = octal number (ooo is 0 to 3 digits)
27			\xhhh = hexadecimal number (hhh is 1 to 3 digits)
28
29			Additional directive:
30
31			%b = print an argument string, interpreting backslash escapes
32
33			The 'format' argument is re-used as many times as necessary
34			to convert all of the given arguments.
35
36	niro	816	David MacKenzie <djm@gnu.ai.mit.edu>
37			*/
38	niro	532
39			// 19990508 Busy Boxed! Dave Cinege
40
41	niro	816	#include "libbb.h"
42	niro	532
43	niro	816	/* A note on bad input: neither bash 3.2 nor coreutils 6.10 stop on it.
44			* They report it:
45			* bash: printf: XXX: invalid number
46			* printf: XXX: expected a numeric value
47			* bash: printf: 123XXX: invalid number
48			* printf: 123XXX: value not completely converted
49			* but then they use 0 (or partially converted numeric prefix) as a value
50			* and continue. They exit with 1 in this case.
51			* Both accept insane field width/precision (e.g. %9999999999.9999999999d).
52			* Both print error message and assume 0 if %.f width/precision is "bad"
53			* (but negative numbers are not "bad").
54			* Both accept negative numbers for %u specifier.
55			*
56			* We try to be compatible. We are not compatible here:
57			* - we do not accept -NUM for %u
58			* - exit code is 0 even if "invalid number" was seen (FIXME)
59			* See "if (errno)" checks in the code below.
60			*/
61	niro	532
62	niro	816	typedef void FAST_FUNC (converter)(const char arg, void *result);
63	niro	532
64	niro	816	static int multiconvert(const char arg, void result, converter convert)
65	niro	532	{
66			if (arg == '"' \|\| arg == '\'') {
67	niro	816	arg = utoa((unsigned char)arg[1]);
68	niro	532	}
69	niro	816	errno = 0;
70	niro	532	convert(arg, result);
71	niro	816	if (errno) {
72			bb_error_msg("%s: invalid number", arg);
73			return 1;
74			}
75			return 0;
76	niro	532	}
77
78	niro	816	static void FAST_FUNC conv_strtoul(const char arg, void result)
79	niro	532	{
80	niro	816	(unsigned long)result = bb_strtoul(arg, NULL, 0);
81	niro	532	}
82	niro	816	static void FAST_FUNC conv_strtol(const char arg, void result)
83	niro	532	{
84	niro	816	(long)result = bb_strtol(arg, NULL, 0);
85	niro	532	}
86	niro	816	static void FAST_FUNC conv_strtod(const char arg, void result)
87	niro	532	{
88			char *end;
89	niro	816	/* Well, this one allows leading whitespace... so what? */
90			/* What I like much less is that "-" accepted too! :( */
91	niro	532	(double)result = strtod(arg, &end);
92	niro	816	if (end[0]) {
93			errno = ERANGE;
94			(double)result = 0;
95			}
96	niro	532	}
97
98	niro	816	/* Callers should check errno to detect errors */
99			static unsigned long my_xstrtoul(const char *arg)
100	niro	532	{
101			unsigned long result;
102	niro	816	if (multiconvert(arg, &result, conv_strtoul))
103			result = 0;
104	niro	532	return result;
105			}
106	niro	816	static long my_xstrtol(const char *arg)
107	niro	532	{
108			long result;
109	niro	816	if (multiconvert(arg, &result, conv_strtol))
110			result = 0;
111	niro	532	return result;
112			}
113	niro	816	static double my_xstrtod(const char *arg)
114	niro	532	{
115			double result;
116			multiconvert(arg, &result, conv_strtod);
117			return result;
118			}
119
120			static void print_esc_string(char *str)
121			{
122	niro	816	while (*str) {
123	niro	532	if (*str == '\\') {
124			str++;
125	niro	816	bb_putchar(bb_process_escape_sequence((const char **)&str));
126	niro	532	} else {
127	niro	816	bb_putchar(*str);
128			str++;
129	niro	532	}
130			}
131			}
132
133	niro	816	static void print_direc(char *format, unsigned fmt_length,
134			int field_width, int precision,
135			const char *argument)
136	niro	532	{
137	niro	816	long lv;
138			double dv;
139			char saved;
140			char have_prec, have_width;
141	niro	532
142	niro	816	saved = format[fmt_length];
143			format[fmt_length] = '\0';
144	niro	532
145	niro	816	have_prec = strstr(format, ".*");
146			have_width = strchr(format, '*');
147			if (have_width - 1 == have_prec)
148			have_width = NULL;
149	niro	532
150	niro	816	switch (format[fmt_length - 1]) {
151			case 'c':
152			printf(format, *argument);
153			break;
154			case 'd':
155			case 'i':
156			lv = my_xstrtol(argument);
157			print_long:
158			/* if (errno) return; - see comment at the top */
159			if (!have_width) {
160			if (!have_prec)
161			printf(format, lv);
162			else
163			printf(format, precision, lv);
164			} else {
165			if (!have_prec)
166			printf(format, field_width, lv);
167			else
168			printf(format, field_width, precision, lv);
169			}
170			break;
171			case 'o':
172			case 'u':
173			case 'x':
174			case 'X':
175			lv = my_xstrtoul(argument);
176			/* cheat: unsigned long and long have same width, so... */
177			goto print_long;
178			case 's':
179			/* Are char* and long the same? (true for most arches) */
180			if (sizeof(argument) == sizeof(lv)) {
181			lv = (long)(ptrdiff_t)argument;
182			goto print_long;
183			} else { /* Hope compiler will optimize it out */
184			if (!have_width) {
185			if (!have_prec)
186			printf(format, argument);
187			else
188			printf(format, precision, argument);
189			} else {
190			if (!have_prec)
191			printf(format, field_width, argument);
192			else
193			printf(format, field_width, precision, argument);
194			}
195			break;
196			}
197			case 'f':
198			case 'e':
199			case 'E':
200			case 'g':
201			case 'G':
202			dv = my_xstrtod(argument);
203			/* if (errno) return; */
204			if (!have_width) {
205			if (!have_prec)
206			printf(format, dv);
207			else
208			printf(format, precision, dv);
209			} else {
210			if (!have_prec)
211			printf(format, field_width, dv);
212			else
213			printf(format, field_width, precision, dv);
214			}
215			break;
216			} /* switch */
217	niro	532
218	niro	816	format[fmt_length] = saved;
219			}
220	niro	532
221	niro	816	/* Handle params for "%.f". Negative numbers are ok (compat). */
222			static int get_width_prec(const char *str)
223			{
224			int v = bb_strtoi(str, NULL, 10);
225			if (errno) {
226			bb_error_msg("%s: invalid number", str);
227			v = 0;
228			}
229			return v;
230	niro	532	}
231
232	niro	816	/* Print the text in FORMAT, using ARGV for arguments to any '%' directives.
233			Return advanced ARGV. */
234			static char *print_formatted(char f, char **argv)
235	niro	532	{
236	niro	816	char direc_start; / Start of % directive. */
237			unsigned direc_length; /* Length of % directive. */
238			int field_width; /* Arg to first '' /
239			int precision; /* Arg to second '' /
240			char **saved_argv = argv;
241	niro	532
242	niro	816	for (; *f; ++f) {
243	niro	532	switch (*f) {
244			case '%':
245			direc_start = f++;
246			direc_length = 1;
247	niro	816	field_width = precision = 0;
248	niro	532	if (*f == '%') {
249	niro	816	bb_putchar('%');
250	niro	532	break;
251			}
252			if (*f == 'b') {
253	niro	816	if (*argv) {
254	niro	532	print_esc_string(*argv);
255			++argv;
256			}
257			break;
258			}
259			if (strchr("-+ #", *f)) {
260			++f;
261			++direc_length;
262			}
263			if (f == '') {
264			++f;
265			++direc_length;
266	niro	816	if (*argv)
267			field_width = get_width_prec(*argv++);
268			} else {
269	niro	532	while (isdigit(*f)) {
270			++f;
271			++direc_length;
272			}
273	niro	816	}
274	niro	532	if (*f == '.') {
275			++f;
276			++direc_length;
277			if (f == '') {
278			++f;
279			++direc_length;
280	niro	816	if (*argv)
281			precision = get_width_prec(*argv++);
282			} else {
283	niro	532	while (isdigit(*f)) {
284			++f;
285			++direc_length;
286			}
287	niro	816	}
288	niro	532	}
289	niro	816	/* Remove size modifiers - "%Ld" would try to printf
290			* long long, we pass long, and it spews garbage */
291			if ((f \| 0x20) == 'l' \|\| f == 'h' \|\| *f == 'z') {
292			overlapping_strcpy(f, f + 1);
293	niro	532	}
294	niro	816	//FIXME: actually, the same happens with bare "%d":
295			//it printfs an int, but we pass long!
296			//What saves us is that on most arches stack slot
297			//is pointer-sized -> long-sized -> ints are promoted to longs
298			// for variadic functions -> printf("%d", int_v) is in reality
299			// indistinqushable from printf("%d", long_v) ->
300			// since printf("%d", int_v) works, printf("%d", long_v) has to work.
301			//But "clean" solution would be to add "l" to d,i,o,x,X.
302			//Probably makes sense to go all the way to "ll" then.
303			//Coreutils support long long-sized arguments.
304
305			/* needed - try "printf %" without it */
306			if (!strchr("diouxXfeEgGcs", *f)) {
307			bb_error_msg("%s: invalid format", direc_start);
308			/* causes main() to exit with error */
309			return saved_argv - 1;
310			}
311	niro	532	++direc_length;
312	niro	816	if (*argv) {
313	niro	532	print_direc(direc_start, direc_length, field_width,
314			precision, *argv);
315			++argv;
316	niro	816	} else {
317	niro	532	print_direc(direc_start, direc_length, field_width,
318			precision, "");
319	niro	816	}
320			/* if (errno) return saved_argv - 1; */
321	niro	532	break;
322			case '\\':
323	niro	816	if (*++f == 'c') {
324			return saved_argv; /* causes main() to exit */
325			}
326			bb_putchar(bb_process_escape_sequence((const char **)&f));
327	niro	532	f--;
328			break;
329			default:
330	niro	816	bb_putchar(*f);
331	niro	532	}
332			}
333
334	niro	816	return argv;
335	niro	532	}
336
337	niro	816	int printf_main(int argc UNUSED_PARAM, char **argv)
338	niro	532	{
339	niro	816	char *format;
340			char **argv2;
341	niro	532
342	niro	816	/* We must check that stdout is not closed.
343			* The reason for this is highly non-obvious.
344			* printf_main is used from shell.
345			* Shell must correctly handle 'printf "%s" foo'
346			* if stdout is closed. With stdio, output gets shoveled into
347			* stdout buffer, and even fflush cannot clear it out. It seems that
348			* even if libc receives EBADF on write attempts, it feels determined
349			* to output data no matter what. So it will try later,
350			* and possibly will clobber future output. Not good. */
351			// TODO: check fcntl() & O_ACCMODE == O_WRONLY or O_RDWR?
352			if (fcntl(1, F_GETFL) == -1)
353			return 1; /* match coreutils 6.10 (sans error msg to stderr) */
354			//if (dup2(1, 1) != 1) - old way
355			// return 1;
356	niro	532
357	niro	816	/* bash builtin errors out on "printf '-%s-\n' foo",
358			* coreutils-6.9 works. Both work with "printf -- '-%s-\n' foo".
359			* We will mimic coreutils. */
360			if (argv[1] && argv[1][0] == '-' && argv[1][1] == '-' && !argv[1][2])
361			argv++;
362			if (!argv[1]) {
363			if (ENABLE_ASH_BUILTIN_PRINTF
364			&& applet_name[0] != 'p'
365			) {
366			bb_error_msg("usage: printf FORMAT [ARGUMENT...]");
367			return 2; /* bash compat */
368	niro	532	}
369	niro	816	bb_show_usage();
370			}
371	niro	532
372	niro	816	format = argv[1];
373			argv2 = argv + 2;
374	niro	532
375	niro	816	do {
376			argv = argv2;
377			argv2 = print_formatted(format, argv);
378			} while (argv2 > argv && *argv2);
379	niro	532
380	niro	816	/* coreutils compat (bash doesn't do this):
381			if (*argv)
382			fprintf(stderr, "excess args ignored");
383			*/
384	niro	532
385	niro	816	return (argv2 < argv); /* if true, print_formatted errored out */
386	niro	532	}