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Diffstat (limited to '')
-rw-r--r-- | examples/loadables/seq.c | 490 |
1 files changed, 490 insertions, 0 deletions
diff --git a/examples/loadables/seq.c b/examples/loadables/seq.c new file mode 100644 index 0000000..d8f3e0a --- /dev/null +++ b/examples/loadables/seq.c @@ -0,0 +1,490 @@ +/* seq - print sequence of numbers to standard output. + Copyright (C) 2018 Free Software Foundation, Inc. + + 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 3 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, see <https://www.gnu.org/licenses/>. */ + +/* Written as bash builtin by Chet Ramey. Portions from seq.c by Ulrich Drepper. */ + +#include <config.h> + +#include <sys/types.h> + +#ifdef HAVE_UNISTD_H +# include <unistd.h> +#endif + +#include <stdio.h> +#include <errno.h> + +#include "bashansi.h" +#include "loadables.h" +#include "bashintl.h" + +#ifndef errno +extern int errno; +#endif + +#if defined (HAVE_LONG_DOUBLE) && HAVE_DECL_STRTOLD && !defined(STRTOLD_BROKEN) +typedef long double floatmax_t; +# define FLOATMAX_CONV "L" +# define strtofltmax strtold +# define FLOATMAX_FMT "%Lg" +# define FLOATMAX_WFMT "%0.Lf" +# define USE_LONG_DOUBLE +#else +typedef double floatmax_t; +# define FLOATMAX_CONV "" +# define strtofltmax strtod +# define FLOATMAX_FMT "%g" +# define FLOATMAX_WFMT "%0.f" +#endif +static floatmax_t getfloatmax __P((const char *)); +static char *genformat __P((floatmax_t, floatmax_t, floatmax_t)); + +#define MAX(a, b) (((a) < (b))? (b) : (a)) + +static int conversion_error = 0; + +/* If true print all number with equal width. */ +static int equal_width; + +/* The string used to separate two numbers. */ +static char const *separator; + +/* The string output after all numbers have been output. */ +static char const terminator[] = "\n"; + +static char decimal_point; + +/* Pretty much the same as the version in builtins/printf.def */ +static floatmax_t +getfloatmax (arg) + const char *arg; +{ + floatmax_t ret; + char *ep; + + errno = 0; + ret = strtofltmax (arg, &ep); + + if (*ep) + { + sh_invalidnum ((char *)arg); + conversion_error = 1; + } + else if (errno == ERANGE) + { + builtin_error ("warning: %s: %s", arg, strerror(ERANGE)); + conversion_error = 1; + } + + if (ret == -0.0) + ret = 0.0; + + return (ret); +} + +/* If FORMAT is a valid printf format for a double argument, return + its long double equivalent, allocated from dynamic storage. This + was written by Ulrich Drepper, taken from coreutils:seq.c */ +static char * +long_double_format (char const *fmt) +{ + size_t i; + size_t length_modifier_offset; + int has_L; + + for (i = 0; ! (fmt[i] == '%' && fmt[i + 1] != '%'); i += (fmt[i] == '%') + 1) + { + if (!fmt[i]) + { + builtin_error ("format %s has no %% directive", fmt); + return 0; + } + } + + i++; + i += strspn (fmt + i, "-+#0 '"); /* zero or more flags */ + i += strspn (fmt + i, "0123456789"); /* optional minimum field width */ + if (fmt[i] == '.') /* optional precision */ + { + i++; + i += strspn (fmt + i, "0123456789"); + } + + length_modifier_offset = i; /* optional length modifier */ + /* we could ignore an 'l' length modifier here */ + has_L = (fmt[i] == 'L'); + i += has_L; + switch (fmt[i]) + { + case '\0': + builtin_error ("format %s ends in %%", fmt); + return 0; + case 'A': + case 'a': + case 'e': + case 'E': + case 'f': + case 'F': + case 'g': + case 'G': + break; + default: + builtin_error ("format %s has unknown `%%%c' directive", fmt, fmt[i]); + return 0; + } + for (i++; ; i += (fmt[i] == '%') + 1) + if (fmt[i] == '%' && fmt[i + 1] != '%') + { + builtin_error ("format %s has too many %% directives", fmt); + return 0; + } + else if (fmt[i] == 0) + { + size_t format_size = i + 1; + char *ldfmt = xmalloc (format_size + 1); + memcpy (ldfmt, fmt, length_modifier_offset); +#ifdef USE_LONG_DOUBLE + ldfmt[length_modifier_offset] = 'L'; + strcpy (ldfmt + length_modifier_offset + 1, + fmt + length_modifier_offset + has_L); +#else + strcpy (ldfmt + length_modifier_offset, fmt + length_modifier_offset); +#endif + return ldfmt; + } +} + +/* Return the number of digits following the decimal point in NUMBUF */ +static int +getprec (numbuf) + const char *numbuf; +{ + int p; + char *dp; + + if (dp = strchr (numbuf, decimal_point)) + dp++; /* skip over decimal point */ + for (p = 0; dp && *dp && ISDIGIT (*dp); dp++) + p++; + return p; +} + +/* Return the default format given FIRST, INCR, and LAST. */ +static char * +genformat (first, incr, last) + floatmax_t first, incr, last; +{ + static char buf[6 + 2 * INT_STRLEN_BOUND (int)]; + int wfirst, wlast, width; + int iprec, fprec, lprec, prec; + + if (equal_width == 0) + return (FLOATMAX_FMT); + + /* OK, we have to figure out the largest number of decimal places. This is + a little more expensive than using the original strings. */ + snprintf (buf, sizeof (buf), FLOATMAX_FMT, incr); + iprec = getprec (buf); + + wfirst = snprintf (buf, sizeof (buf), FLOATMAX_FMT, first); + fprec = getprec (buf); + + prec = MAX (fprec, iprec); + + wlast = snprintf (buf, sizeof (buf), FLOATMAX_FMT, last); + lprec = getprec (buf); + + /* increase first width by any increased precision in increment */ + wfirst += (prec - fprec); + + /* adjust last width to use precision from first/incr */ + wlast += (prec - lprec); + + if (lprec && prec == 0) + wlast--; /* no decimal point */ + if (lprec == 0 && prec) + wlast++; /* include decimal point */ + if (fprec == 0 && prec) + wfirst++; /* include decimal point */ + + width = MAX (wfirst, wlast); + if (width) + sprintf (buf, "%%0%d.%d%sf", width, prec, FLOATMAX_CONV); + else + sprintf (buf, "%%.%d%sf", prec, FLOATMAX_CONV); + + return buf; +} + +int +print_fltseq (fmt, first, last, incr) + const char *fmt; + floatmax_t first, last, incr; +{ + int n; + floatmax_t next; + const char *s; + + n = 0; /* interation counter */ + s = ""; + for (next = first; incr >= 0 ? (next <= last) : (next >= last); next = first + n * incr) + { + QUIT; + if (*s && fputs (s, stdout) == EOF) + return (sh_chkwrite (EXECUTION_FAILURE)); + if (printf (fmt, next) < 0) + return (sh_chkwrite (EXECUTION_FAILURE)); + s = separator; + n++; + } + + if (n > 0 && fputs (terminator, stdout) == EOF) + return (sh_chkwrite (EXECUTION_FAILURE)); + return (sh_chkwrite (EXECUTION_SUCCESS)); +} + +/* must be <= INT_STRLEN_BOUND(intmax_t) */ +int +width_needed (num) + intmax_t num; +{ + int ret; + + ret = num < 0; /* sign */ + if (ret) + num = -num; + do + ret++; + while (num /= 10); + return ret; +} + +int +print_intseq (ifirst, ilast, iincr) + intmax_t ifirst, ilast, iincr; +{ + char intwfmt[6 + INT_STRLEN_BOUND(int) + sizeof (PRIdMAX)]; + const char *s; + intmax_t i, next; + + /* compute integer format string */ + if (equal_width) /* -w supplied */ + { + int wfirst, wlast, width; + + wfirst = width_needed (ifirst); + wlast = width_needed (ilast); + width = MAX(wfirst, wlast); + + /* The leading %s is for the separator */ + snprintf (intwfmt, sizeof (intwfmt), "%%s%%0%u" PRIdMAX, width); + } + + /* We could use braces.c:mkseq here but that allocates lots of memory */ + s = ""; + for (i = ifirst; (ifirst <= ilast) ? (i <= ilast) : (i >= ilast); i = next) + { + QUIT; + /* The leading %s is for the separator */ + if (printf (equal_width ? intwfmt : "%s%" PRIdMAX, s, i) < 0) + return (sh_chkwrite (EXECUTION_FAILURE)); + s = separator; + next = i + iincr; + } + + if (fputs (terminator, stdout) == EOF) + return (sh_chkwrite (EXECUTION_FAILURE)); + return (sh_chkwrite (EXECUTION_SUCCESS)); +} + +int +seq_builtin (list) + WORD_LIST *list; +{ + floatmax_t first, last, incr; + intmax_t ifirst, ilast, iincr; + WORD_LIST *l; + int opt, nargs, intseq, freefmt; + char *first_str, *incr_str, *last_str; + char const *fmtstr; /* The printf(3) format used for output. */ + + equal_width = 0; + separator = "\n"; + fmtstr = NULL; + + first = 1.0; + last = 0.0; + incr = 0.0; /* set later */ + ifirst = ilast = iincr = 0; + first_str = incr_str = last_str = 0; + + intseq = freefmt = 0; + opt = 0; + + reset_internal_getopt (); + while (opt != -1) + { + l = lcurrent ? lcurrent : list; + if (l && l->word && l->word->word && l->word->word[0] == '-' && + (l->word->word[1] == '.' || DIGIT (l->word->word[1]))) + { + loptend = l; + break; /* negative number */ + } + if ((opt = internal_getopt (list, "f:s:w")) == -1) + break; + + switch (opt) + { + case 'f': + fmtstr = list_optarg; + break; + case 's': + separator = list_optarg; + break; + case 'w': + equal_width = 1; + break; + CASE_HELPOPT; + default: + builtin_usage (); + return (EX_USAGE); + } + } + list = loptend; + + if (list == 0) + { + builtin_usage (); + return (EXECUTION_FAILURE); + } + + for (nargs = 1, l = list; l->next; l = l->next) + nargs++; + if (nargs > 3) + { + builtin_usage (); + return (EXECUTION_FAILURE); + } + + /* LAST */ + conversion_error = 0; + last = getfloatmax (last_str = l->word->word); + if (conversion_error) + return (EXECUTION_FAILURE); + + /* FIRST LAST */ + if (nargs > 1) + { + conversion_error = 0; + first = getfloatmax (first_str = list->word->word); + if (conversion_error) + return (EXECUTION_FAILURE); + } + + /* FIRST INCR LAST */ + if (nargs > 2) + { + conversion_error = 0; + incr = getfloatmax (incr_str = list->next->word->word); + if (conversion_error) + return (EXECUTION_FAILURE); + if (incr == 0.0) + { + builtin_error ("zero %screment", (first < last) ? "in" : "de"); + return (EXECUTION_FAILURE); + } + } + + /* Sanitize arguments */ + if (incr == 0.0) + incr = (first <= last) ? 1.0 : -1.0; + if ((incr < 0.0 && first < last) || (incr > 0 && first > last)) + { + builtin_error ("incorrect %screment", (first < last) ? "in" : "de"); + return (EXECUTION_FAILURE); + } + + /* validate format here */ + if (fmtstr) + { + fmtstr = long_double_format (fmtstr); + freefmt = 1; + if (fmtstr == 0) + return (EXECUTION_FAILURE); + } + + if (fmtstr != NULL && equal_width) + { + builtin_warning ("-w ignored when the format string is specified"); + equal_width = 0; + } + + /* Placeholder for later additional conditions */ + if (last_str && all_digits (last_str) && + (first_str == 0 || all_digits (first_str)) && + (incr_str == 0 || all_digits (incr_str)) && + fmtstr == NULL) + intseq = 1; + + if (intseq) + { + ifirst = (intmax_t)first; /* truncation */ + ilast = (intmax_t)last; + iincr = (intmax_t)incr; + + return (print_intseq (ifirst, ilast, iincr)); + } + + decimal_point = locale_decpoint (); + if (fmtstr == NULL) + fmtstr = genformat (first, incr, last); + + print_fltseq (fmtstr, first, last, incr); + + if (freefmt) + free ((void *)fmtstr); + return sh_chkwrite (EXECUTION_SUCCESS); +} + +/* Taken largely from GNU seq. */ +char *seq_doc[] = { + "Print numbers from FIRST to LAST, in steps of INCREMENT.", + "", + "-f FORMAT use printf style floating-point FORMAT", + "-s STRING use STRING to separate numbers (default: \\n)", + "-w equalize width by padding with leading zeroes", + "", + "If FIRST or INCREMENT is omitted, it defaults to 1. However, an", + "omitted INCREMENT defaults to -1 when LAST is smaller than FIRST.", + "The sequence of numbers ends when the sum of the current number and", + "INCREMENT would become greater than LAST.", + "FIRST, INCREMENT, and LAST are interpreted as floating point values.", + "", + "FORMAT must be suitable for printing one argument of type 'double';", + "it defaults to %.PRECf if FIRST, INCREMENT, and LAST are all fixed point", + "decimal numbers with maximum precision PREC, and to %g otherwise.", + (char *)NULL +}; + +struct builtin seq_struct = { + "seq", + seq_builtin, + BUILTIN_ENABLED, + seq_doc, + "seq [-f format] [-s separator] [-w] [FIRST [INCR]] LAST", + 0 +}; |