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Diffstat (limited to 'coreutils/printf.c')
| -rw-r--r-- | coreutils/printf.c | 386 |
1 files changed, 386 insertions, 0 deletions
diff --git a/coreutils/printf.c b/coreutils/printf.c new file mode 100644 index 0000000..ca8e51c --- /dev/null +++ b/coreutils/printf.c @@ -0,0 +1,386 @@ +/* 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 */ +} |