1 /*- 2 * Copyright (c) 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Kevin Ruddy. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 static const char copyright[] = 39 "@(#) Copyright (c) 1990, 1993\n\ 40 The Regents of the University of California. All rights reserved.\n"; 41 #endif /* not lint */ 42 43 #ifndef lint 44 #if 0 45 static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93"; 46 #endif 47 #endif /* not lint */ 48 49 #include <sys/cdefs.h> 50 __FBSDID("$FreeBSD$"); 51 52 #include <err.h> 53 #include <limits.h> 54 #include <locale.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 #include <wchar.h> 60 #include <wctype.h> 61 62 #define DEFLINEWIDTH 80 63 64 void fold(int); 65 static int newpos(int, wint_t); 66 static void usage(void); 67 68 int bflag; /* Count bytes, not columns */ 69 int sflag; /* Split on word boundaries */ 70 71 int 72 main(int argc, char **argv) 73 { 74 int ch; 75 int rval, width; 76 char *p; 77 78 (void) setlocale(LC_CTYPE, ""); 79 80 width = -1; 81 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1) 82 switch (ch) { 83 case 'b': 84 bflag = 1; 85 break; 86 case 's': 87 sflag = 1; 88 break; 89 case 'w': 90 if ((width = atoi(optarg)) <= 0) { 91 errx(1, "illegal width value"); 92 } 93 break; 94 case '0': case '1': case '2': case '3': case '4': 95 case '5': case '6': case '7': case '8': case '9': 96 if (width == -1) { 97 p = argv[optind - 1]; 98 if (p[0] == '-' && p[1] == ch && !p[2]) 99 width = atoi(++p); 100 else 101 width = atoi(argv[optind] + 1); 102 } 103 break; 104 default: 105 usage(); 106 } 107 argv += optind; 108 argc -= optind; 109 110 if (width == -1) 111 width = DEFLINEWIDTH; 112 rval = 0; 113 if (!*argv) 114 fold(width); 115 else for (; *argv; ++argv) 116 if (!freopen(*argv, "r", stdin)) { 117 warn("%s", *argv); 118 rval = 1; 119 } else 120 fold(width); 121 exit(rval); 122 } 123 124 static void 125 usage(void) 126 { 127 (void)fprintf(stderr, "usage: fold [-bs] [-w width] [file ...]\n"); 128 exit(1); 129 } 130 131 /* 132 * Fold the contents of standard input to fit within WIDTH columns (or bytes) 133 * and write to standard output. 134 * 135 * If sflag is set, split the line at the last space character on the line. 136 * This flag necessitates storing the line in a buffer until the current 137 * column > width, or a newline or EOF is read. 138 * 139 * The buffer can grow larger than WIDTH due to backspaces and carriage 140 * returns embedded in the input stream. 141 */ 142 void 143 fold(int width) 144 { 145 static wchar_t *buf; 146 static int buf_max; 147 int col, i, indx, space; 148 wint_t ch; 149 150 col = indx = 0; 151 while ((ch = getwchar()) != WEOF) { 152 if (ch == '\n') { 153 wprintf(L"%.*ls\n", indx, buf); 154 col = indx = 0; 155 continue; 156 } 157 if ((col = newpos(col, ch)) > width) { 158 if (sflag) { 159 i = indx; 160 while (--i >= 0 && !iswblank(buf[i])) 161 ; 162 space = i; 163 } 164 if (sflag && space != -1) { 165 space++; 166 wprintf(L"%.*ls\n", space, buf); 167 wmemmove(buf, buf + space, indx - space); 168 indx -= space; 169 col = 0; 170 for (i = 0; i < indx; i++) 171 col = newpos(col, buf[i]); 172 } else { 173 wprintf(L"%.*ls\n", indx, buf); 174 col = indx = 0; 175 } 176 col = newpos(col, ch); 177 } 178 if (indx + 1 > buf_max) { 179 buf_max += LINE_MAX; 180 buf = realloc(buf, sizeof(*buf) * buf_max); 181 if (buf == NULL) 182 err(1, "realloc()"); 183 } 184 buf[indx++] = ch; 185 } 186 187 if (indx != 0) 188 wprintf(L"%.*ls", indx, buf); 189 } 190 191 /* 192 * Update the current column position for a character. 193 */ 194 static int 195 newpos(int col, wint_t ch) 196 { 197 char buf[MB_LEN_MAX]; 198 size_t len; 199 int w; 200 201 if (bflag) { 202 len = wcrtomb(buf, ch, NULL); 203 col += len; 204 } else 205 switch (ch) { 206 case '\b': 207 if (col > 0) 208 --col; 209 break; 210 case '\r': 211 col = 0; 212 break; 213 case '\t': 214 col = (col + 8) & ~7; 215 break; 216 default: 217 if ((w = wcwidth(ch)) > 0) 218 col += w; 219 break; 220 } 221 222 return (col); 223 } 224