1 /* $NetBSD: unexpand.c,v 1.18 2019/09/13 17:32:29 dyoung Exp $ */ 2 3 /*- 4 * Copyright (c) 1980, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)unexpand.c 8.1 (Berkeley) 6/6/93"; 41 #endif 42 __RCSID("$NetBSD: unexpand.c,v 1.18 2019/09/13 17:32:29 dyoung Exp $"); 43 #endif /* not lint */ 44 45 /* 46 * unexpand - put tabs into a file replacing blanks 47 */ 48 #include <limits.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 #include <unistd.h> 53 #include <errno.h> 54 #include <err.h> 55 #include <util.h> 56 57 58 #define DSTOP 8 59 static int all; 60 static size_t nstops; 61 static size_t maxstops; 62 static size_t *tabstops; 63 64 static void tabify(const char *, size_t); 65 static void usage(void) __attribute__((__noreturn__)); 66 67 static void 68 usage(void) 69 { 70 (void)fprintf(stderr, "Usage: %s [-a] [-t tabstop] [file ...]\n", 71 getprogname()); 72 exit(EXIT_FAILURE); 73 } 74 75 int 76 main(int argc, char **argv) 77 { 78 int c; 79 char *ep, *tab; 80 char *line; 81 size_t len; 82 unsigned long i; 83 84 setprogname(argv[0]); 85 86 while ((c = getopt(argc, argv, "at:")) != -1) { 87 switch (c) { 88 case 'a': 89 all = 1; 90 break; 91 case 't': 92 while ((tab = strsep(&optarg, ", \t")) != NULL) { 93 if (*tab == '\0') 94 continue; 95 errno = 0; 96 i = strtoul(tab, &ep, 0); 97 if (*ep || (errno == ERANGE && i == ULONG_MAX)) 98 errx(EXIT_FAILURE, 99 "Invalid tabstop `%s'", tab); 100 if (nstops >= maxstops) { 101 maxstops += 20; 102 tabstops = erealloc(tabstops, maxstops); 103 } 104 if (nstops && tabstops[nstops - 1] >= (size_t)i) 105 errx(EXIT_FAILURE, 106 "Bad tabstop spec `%s', must be " 107 "greater than the previous `%zu'", 108 tab, tabstops[nstops - 1]); 109 tabstops[nstops++] = i; 110 } 111 break; 112 case '?': 113 default: 114 usage(); 115 } 116 } 117 argc -= optind; 118 argv += optind; 119 120 do { 121 if (argc > 0) { 122 if (freopen(argv[0], "r", stdin) == NULL) 123 err(EXIT_FAILURE, "Cannot open `%s'", argv[0]); 124 argc--, argv++; 125 } 126 while ((line = fgetln(stdin, &len)) != NULL) 127 tabify(line, len); 128 } while (argc > 0); 129 return EXIT_SUCCESS; 130 } 131 132 static void 133 tabify(const char *line, size_t len) 134 { 135 const size_t dstop = (nstops == 0) ? DSTOP : tabstops[0]; 136 const char *e, *p; 137 size_t dcol, ocol, limit, n; 138 139 dcol = ocol = 0; 140 limit = nstops <= 1 ? UINT_MAX : tabstops[nstops - 1] - 1; 141 e = line + len; 142 for (p = line; p < e; p++) { 143 if (*p == ' ') { 144 dcol++; 145 continue; 146 } else if (*p == '\t') { 147 if (nstops <= 1) { 148 dcol = (1 + dcol / dstop) * dstop; 149 continue; 150 } 151 for (n = 0; n < nstops && tabstops[n] <= dcol; n++) 152 continue; 153 if (n < nstops - 1 && tabstops[n] - 1 < limit) { 154 dcol = tabstops[n]; 155 continue; 156 } 157 } 158 159 /* Output our tabs */ 160 if (nstops <= 1) { 161 while (((ocol + dstop) / dstop) <= (dcol / dstop)) { 162 if (dcol - ocol < 2) 163 break; 164 if (putchar('\t') == EOF) 165 goto out; 166 ocol = (1 + ocol / dstop) * dstop; 167 } 168 } else { 169 for (n = 0; n < nstops && tabstops[n] <= ocol; n++) 170 continue; 171 while (n < nstops && tabstops[n] <= dcol && ocol < dcol 172 && ocol < limit) { 173 if (putchar('\t') == EOF) 174 goto out; 175 ocol = tabstops[n++]; 176 } 177 } 178 179 /* Output remaining spaces */ 180 while (ocol < dcol && ocol < limit) { 181 if (putchar(' ') == EOF) 182 goto out; 183 ocol++; 184 } 185 186 /* Output our char */ 187 if (putchar(*p) == EOF) 188 goto out; 189 if (*p == '\b') { 190 if (ocol > 0) { 191 ocol--; 192 dcol--; 193 } 194 } else { 195 ocol++; 196 dcol++; 197 } 198 199 if (all && dcol < limit) 200 continue; /* Collapse the rest of the line. */ 201 202 /* Output remainder of line */ 203 for (p++; p < e; p++) { 204 if (putchar(*p) == EOF) 205 goto out; 206 } 207 return; 208 } 209 return; 210 out: 211 err(EXIT_FAILURE, "write failed"); 212 } 213
Indexes created Sat Sep 20 22:09:52 GMT 2025