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Diffstat (limited to 'text_cmds/fold/fold.c')
| -rw-r--r-- | text_cmds/fold/fold.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/text_cmds/fold/fold.c b/text_cmds/fold/fold.c new file mode 100644 index 0000000..e26356c --- /dev/null +++ b/text_cmds/fold/fold.c @@ -0,0 +1,228 @@ +/*- + * Copyright (c) 1990, 1993 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Kevin Ruddy. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#ifndef lint +static const char copyright[] = +"@(#) Copyright (c) 1990, 1993\n\ + The Regents of the University of California. All rights reserved.\n"; +#endif /* not lint */ + +#ifndef lint +#if 0 +static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; +#endif +#endif /* not lint */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD: src/usr.bin/fold/fold.c,v 1.13 2004/06/24 15:12:29 tjr Exp $"); + +#include <err.h> +#include <limits.h> +#include <locale.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <wchar.h> +#include <wctype.h> + +#define DEFLINEWIDTH 80 + +void fold(int); +static int newpos(int, wint_t); +static void usage(void); + +int bflag; /* Count bytes, not columns */ +int sflag; /* Split on word boundaries */ + +int +main(int argc, char **argv) +{ + int ch; + int rval, width; + char *p; + + (void) setlocale(LC_CTYPE, ""); + + width = -1; + while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) + switch (ch) { + case 'b': + bflag = 1; + break; + case 's': + sflag = 1; + break; + case 'w': + if ((width = atoi(optarg)) <= 0) { + errx(1, "illegal width value"); + } + break; + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + if (width == -1) { + p = argv[optind - 1]; + if (p[0] == '-' && p[1] == ch && !p[2]) + width = atoi(++p); + else + width = atoi(argv[optind] + 1); + } + break; + default: + usage(); + } + argv += optind; + argc -= optind; + + if (width == -1) + width = DEFLINEWIDTH; + rval = 0; + if (!*argv) + fold(width); + else for (; *argv; ++argv) + if (!freopen(*argv, "r", stdin)) { + warn("%s", *argv); + rval = 1; + } else + fold(width); + exit(rval); +} + +static void +usage(void) +{ + (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); + exit(1); +} + +/* + * Fold the contents of standard input to fit within WIDTH columns (or bytes) + * and write to standard output. + * + * If sflag is set, split the line at the last space character on the line. + * This flag necessitates storing the line in a buffer until the current + * column > width, or a newline or EOF is read. + * + * The buffer can grow larger than WIDTH due to backspaces and carriage + * returns embedded in the input stream. + */ +void +fold(int width) +{ + static wchar_t *buf; + static int buf_max; + int col, i, indx, space; + wint_t ch; + + col = indx = 0; + while ((ch = getwchar()) != WEOF) { + if (ch == '\n') { + wprintf(L"%.*ls\n", indx, buf); + col = indx = 0; + continue; + } + if ((col = newpos(col, ch)) > width) { + if (sflag) { + i = indx; + while (--i >= 0 && !iswblank(buf[i])) + ; + space = i; + } + if (sflag && space != -1) { + space++; + wprintf(L"%.*ls\n", space, buf); + wmemmove(buf, buf + space, indx - space); + indx -= space; + col = 0; + for (i = 0; i < indx; i++) + col = newpos(col, buf[i]); + } else { + wprintf(L"%.*ls\n", indx, buf); + col = indx = 0; + } + col = newpos(col, ch); + } + if (indx + 1 > buf_max) { + buf_max += LINE_MAX; + buf = realloc(buf, sizeof(*buf) * buf_max); + if (buf == NULL) + err(1, "realloc()"); + } + buf[indx++] = ch; + } + + if (ferror(stdin)) { + fprintf(stderr, "Input error\n"); + exit(EXIT_FAILURE); + } + + if (indx != 0) + wprintf(L"%.*ls", indx, buf); +} + +/* + * Update the current column position for a character. + */ +static int +newpos(int col, wint_t ch) +{ + char buf[MB_LEN_MAX]; + size_t len; + int w; + + if (bflag) { + len = wcrtomb(buf, ch, NULL); + col += len; + } else + switch (ch) { + case '\b': + if (col > 0) + --col; + break; + case '\r': + col = 0; + break; + case '\t': + col = (col + 8) & ~7; + break; + default: + if ((w = wcwidth(ch)) > 0) + col += w; + break; + } + + return (col); +} |