1 /* vi: set sw=4 ts=4: */
2 /* printf - format and print data
4 * Copyright 1999 Dave Cinege
5 * Portions copyright (C) 1990-1996 Free Software Foundation, Inc.
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
9 /* Usage: printf format [argument...]
11 * A front end to the printf function that lets it be used from the shell.
19 * \c = produce no further output
22 * \r = carriage return
25 * \0ooo = octal number (ooo is 0 to 3 digits)
26 * \xhhh = hexadecimal number (hhh is 1 to 3 digits)
28 * Additional directive:
30 * %b = print an argument string, interpreting backslash escapes
32 * The 'format' argument is re-used as many times as necessary
33 * to convert all of the given arguments.
35 * David MacKenzie <djm@gnu.ai.mit.edu>
37 /* 19990508 Busy Boxed! Dave Cinege */
39 //config:config PRINTF
40 //config: bool "printf (3.3 kb)"
43 //config: printf is used to format and print specified strings.
44 //config: It's similar to 'echo' except it has more options.
46 //applet:IF_PRINTF(APPLET_NOFORK(printf, printf, BB_DIR_USR_BIN, BB_SUID_DROP, printf))
48 //kbuild:lib-$(CONFIG_PRINTF) += printf.o
49 //kbuild:lib-$(CONFIG_ASH_PRINTF) += printf.o
50 //kbuild:lib-$(CONFIG_HUSH_PRINTF) += printf.o
52 //usage:#define printf_trivial_usage
53 //usage: "FORMAT [ARG]..."
54 //usage:#define printf_full_usage "\n\n"
55 //usage: "Format and print ARG(s) according to FORMAT (a-la C printf)"
57 //usage:#define printf_example_usage
58 //usage: "$ printf \"Val=%d\\n\" 5\n"
63 /* A note on bad input: neither bash 3.2 nor coreutils 6.10 stop on it.
65 * bash: printf: XXX: invalid number
66 * printf: XXX: expected a numeric value
67 * bash: printf: 123XXX: invalid number
68 * printf: 123XXX: value not completely converted
69 * but then they use 0 (or partially converted numeric prefix) as a value
70 * and continue. They exit with 1 in this case.
71 * Both accept insane field width/precision (e.g. %9999999999.9999999999d).
72 * Both print error message and assume 0 if %*.*f width/precision is "bad"
73 * (but negative numbers are not "bad").
74 * Both accept negative numbers for %u specifier.
76 * We try to be compatible.
79 typedef void FAST_FUNC (*converter)(const char *arg, void *result);
81 static int multiconvert(const char *arg, void *result, converter convert)
83 if (*arg == '"' || *arg == '\'') {
84 arg = utoa((unsigned char)arg[1]);
89 bb_error_msg("invalid number '%s'", arg);
95 static void FAST_FUNC conv_strtoull(const char *arg, void *result)
97 *(unsigned long long*)result = bb_strtoull(arg, NULL, 0);
98 /* both coreutils 6.10 and bash 3.2:
104 *(unsigned long long*)result = bb_strtoll(arg, NULL, 0);
107 static void FAST_FUNC conv_strtoll(const char *arg, void *result)
109 *(long long*)result = bb_strtoll(arg, NULL, 0);
111 static void FAST_FUNC conv_strtod(const char *arg, void *result)
114 /* Well, this one allows leading whitespace... so what? */
115 /* What I like much less is that "-" accepted too! :( */
116 *(double*)result = strtod(arg, &end);
119 *(double*)result = 0;
123 /* Callers should check errno to detect errors */
124 static unsigned long long my_xstrtoull(const char *arg)
126 unsigned long long result;
127 if (multiconvert(arg, &result, conv_strtoull))
131 static long long my_xstrtoll(const char *arg)
134 if (multiconvert(arg, &result, conv_strtoll))
138 static double my_xstrtod(const char *arg)
141 multiconvert(arg, &result, conv_strtod);
145 /* Handles %b; return 1 if output is to be short-circuited by \c */
146 static int print_esc_string(const char *str)
149 while ((c = *str) != '\0') {
152 /* %b also accepts 4-digit octals of the form \0### */
154 if ((unsigned char)(str[1] - '0') < 8) {
155 /* 2nd char is 0..7: skip leading '0' */
159 else if (*str == 'c') {
163 /* optimization: don't force arg to be on-stack,
164 * use another variable for that. */
166 c = bb_process_escape_sequence(&z);
176 static void print_direc(char *format, unsigned fmt_length,
177 int field_width, int precision,
178 const char *argument)
183 char *have_prec, *have_width;
185 saved = format[fmt_length];
186 format[fmt_length] = '\0';
188 have_prec = strstr(format, ".*");
189 have_width = strchr(format, '*');
190 if (have_width - 1 == have_prec)
195 switch (format[fmt_length - 1]) {
197 printf(format, *argument);
201 llv = my_xstrtoll(argument);
207 printf(format, precision, llv);
210 printf(format, field_width, llv);
212 printf(format, field_width, precision, llv);
219 llv = my_xstrtoull(argument);
220 /* cheat: unsigned long and long have same width, so... */
223 /* Are char* and long long the same? */
224 if (sizeof(argument) == sizeof(llv)) {
225 llv = (long long)(ptrdiff_t)argument;
228 /* Hope compiler will optimize it out by moving call
229 * instruction after the ifs... */
232 printf(format, argument, /*unused:*/ argument, argument);
234 printf(format, precision, argument, /*unused:*/ argument);
237 printf(format, field_width, argument, /*unused:*/ argument);
239 printf(format, field_width, precision, argument);
248 dv = my_xstrtod(argument);
253 printf(format, precision, dv);
256 printf(format, field_width, dv);
258 printf(format, field_width, precision, dv);
263 format[fmt_length] = saved;
266 /* Handle params for "%*.*f". Negative numbers are ok (compat). */
267 static int get_width_prec(const char *str)
269 int v = bb_strtoi(str, NULL, 10);
271 bb_error_msg("invalid number '%s'", str);
277 /* Print the text in FORMAT, using ARGV for arguments to any '%' directives.
278 Return advanced ARGV. */
279 static char **print_formatted(char *f, char **argv, int *conv_err)
281 char *direc_start; /* Start of % directive. */
282 unsigned direc_length; /* Length of % directive. */
283 int field_width; /* Arg to first '*' */
284 int precision; /* Arg to second '*' */
285 char **saved_argv = argv;
292 field_width = precision = 0;
299 if (print_esc_string(*argv))
300 return saved_argv; /* causes main() to exit */
305 if (*f && strchr("-+ #", *f)) {
313 field_width = get_width_prec(*argv++);
315 while (isdigit(*f)) {
327 precision = get_width_prec(*argv++);
329 while (isdigit(*f)) {
336 /* Remove "lLhz" size modifiers, repeatedly.
337 * bash does not like "%lld", but coreutils
338 * happily takes even "%Llllhhzhhzd"!
339 * We are permissive like coreutils */
340 while ((*f | 0x20) == 'l' || *f == 'h' || *f == 'z') {
341 overlapping_strcpy(f, f + 1);
343 /* Add "ll" if integer modifier, then print */
345 static const char format_chars[] ALIGN1 = "diouxXfeEgGcs";
346 char *p = strchr(format_chars, *f);
347 /* needed - try "printf %" without it */
348 if (p == NULL || *f == '\0') {
349 bb_error_msg("%s: invalid format", direc_start);
350 /* causes main() to exit with error */
351 return saved_argv - 1;
354 if (p - format_chars <= 5) {
355 /* it is one of "diouxX" */
356 p = xmalloc(direc_length + 3);
357 memcpy(p, direc_start, direc_length);
358 p[direc_length + 1] = p[direc_length - 1];
359 p[direc_length - 1] = 'l';
360 p[direc_length] = 'l';
361 //bb_error_msg("<%s>", p);
368 print_direc(direc_start, direc_length, field_width,
371 print_direc(direc_start, direc_length, field_width,
380 return saved_argv; /* causes main() to exit */
382 bb_putchar(bb_process_escape_sequence((const char **)&f));
393 int printf_main(int argc UNUSED_PARAM, char **argv)
399 /* We must check that stdout is not closed.
400 * The reason for this is highly non-obvious.
401 * printf_main is used from shell.
402 * Shell must correctly handle 'printf "%s" foo'
403 * if stdout is closed. With stdio, output gets shoveled into
404 * stdout buffer, and even fflush cannot clear it out. It seems that
405 * even if libc receives EBADF on write attempts, it feels determined
406 * to output data no matter what. So it will try later,
407 * and possibly will clobber future output. Not good. */
408 // TODO: check fcntl() & O_ACCMODE == O_WRONLY or O_RDWR?
409 if (fcntl(1, F_GETFL) == -1)
410 return 1; /* match coreutils 6.10 (sans error msg to stderr) */
411 //if (dup2(1, 1) != 1) - old way
414 /* bash builtin errors out on "printf '-%s-\n' foo",
415 * coreutils-6.9 works. Both work with "printf -- '-%s-\n' foo".
416 * We will mimic coreutils. */
417 if (argv[1] && argv[1][0] == '-' && argv[1][1] == '-' && !argv[1][2])
420 if (ENABLE_ASH_PRINTF
421 && applet_name[0] != 'p'
423 bb_error_msg("usage: printf FORMAT [ARGUMENT...]");
424 return 2; /* bash compat */
435 argv2 = print_formatted(format, argv, &conv_err);
436 } while (argv2 > argv && *argv2);
438 /* coreutils compat (bash doesn't do this):
440 fprintf(stderr, "excess args ignored");
443 return (argv2 < argv) /* if true, print_formatted errored out */
444 || conv_err; /* print_formatted saw invalid number */