file.c revision 1.12
1 /* $NetBSD: file.c,v 1.12 2024/08/14 04:59:51 rin Exp $ */ 2 /* $FreeBSD: head/usr.bin/grep/file.c 211496 2010-08-19 09:28:59Z des $ */ 3 /* $OpenBSD: file.c,v 1.11 2010/07/02 20:48:48 nicm Exp $ */ 4 5 /*- 6 * Copyright (c) 1999 James Howard and Dag-Erling Codan Smrgrav 7 * Copyright (C) 2008-2010 Gabor Kovesdan <gabor (at) FreeBSD.org> 8 * Copyright (C) 2010 Dimitry Andric <dimitry (at) andric.com> 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #if HAVE_NBTOOL_CONFIG_H 34 #include "nbtool_config.h" 35 #endif 36 37 #include <sys/cdefs.h> 38 __RCSID("$NetBSD: file.c,v 1.12 2024/08/14 04:59:51 rin Exp $"); 39 40 #include <sys/param.h> 41 #include <sys/types.h> 42 #include <sys/stat.h> 43 44 #include <err.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <stddef.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <unistd.h> 51 #include <wchar.h> 52 #include <wctype.h> 53 54 #include "grep.h" 55 56 #define MAXBUFSIZ (32 * 1024) 57 #define LNBUFBUMP 80 58 59 #ifndef WITHOUT_GZIP 60 static gzFile gzbufdesc; 61 #endif 62 #ifndef WITHOUT_BZ2 63 static BZFILE* bzbufdesc; 64 #endif 65 66 static unsigned char buffer[MAXBUFSIZ + 1]; 67 static unsigned char *bufpos; 68 static size_t bufrem; 69 70 static unsigned char *lnbuf; 71 static size_t lnbuflen; 72 73 static inline int 74 grep_refill(struct file *f) 75 { 76 ssize_t nr = -1; 77 #ifndef WITHOUT_GZIP 78 int bzerr; 79 #endif 80 81 bufpos = buffer; 82 bufrem = 0; 83 84 #ifndef WITHOUT_GZIP 85 if (filebehave == FILE_GZIP) { 86 nr = gzread(gzbufdesc, buffer, MAXBUFSIZ); 87 if (nr == -1) 88 return -1; 89 } 90 #endif 91 #ifndef WITHOUT_BZ2 92 if (filebehave == FILE_BZIP && bzbufdesc != NULL) { 93 nr = BZ2_bzRead(&bzerr, bzbufdesc, buffer, MAXBUFSIZ); 94 switch (bzerr) { 95 case BZ_OK: 96 case BZ_STREAM_END: 97 /* No problem, nr will be okay */ 98 break; 99 case BZ_DATA_ERROR_MAGIC: 100 /* 101 * As opposed to gzread(), which simply returns the 102 * plain file data, if it is not in the correct 103 * compressed format, BZ2_bzRead() instead aborts. 104 * 105 * So, just restart at the beginning of the file again, 106 * and use plain reads from now on. 107 */ 108 BZ2_bzReadClose(&bzerr, bzbufdesc); 109 bzbufdesc = NULL; 110 if (lseek(f->fd, 0, SEEK_SET) == -1) 111 return (-1); 112 nr = read(f->fd, buffer, MAXBUFSIZ); 113 break; 114 default: 115 /* Make sure we exit with an error */ 116 nr = -1; 117 } 118 if (nr == -1) 119 return -1; 120 } 121 #endif 122 if (nr == -1) { 123 nr = read(f->fd, buffer, MAXBUFSIZ); 124 } 125 126 if (nr < 0) 127 return (-1); 128 129 bufrem = nr; 130 return (0); 131 } 132 133 static inline void 134 grep_lnbufgrow(size_t newlen) 135 { 136 137 if (lnbuflen < newlen) { 138 lnbuf = grep_realloc(lnbuf, newlen); 139 lnbuflen = newlen; 140 } 141 } 142 143 static void 144 grep_copyline(size_t off, size_t len) 145 { 146 memcpy(lnbuf + off, bufpos, len); 147 lnbuf[off + len] = '\0'; 148 } 149 150 char * 151 grep_fgetln(struct file *f, size_t *lenp) 152 { 153 unsigned char *p; 154 size_t len; 155 size_t off; 156 ptrdiff_t diff; 157 158 /* Fill the buffer, if necessary */ 159 if (bufrem == 0 && grep_refill(f) != 0) 160 goto error; 161 162 if (bufrem == 0) { 163 /* Return zero length to indicate EOF */ 164 *lenp = 0; 165 return ((char *)bufpos); 166 } 167 168 /* Look for a newline in the remaining part of the buffer */ 169 if ((p = memchr(bufpos, line_sep, bufrem)) != NULL) { 170 ++p; /* advance over newline */ 171 len = p - bufpos; 172 grep_lnbufgrow(len + 1); 173 grep_copyline(0, len); 174 *lenp = len; 175 bufrem -= len; 176 bufpos = p; 177 return (char *)lnbuf; 178 } 179 180 /* We have to copy the current buffered data to the line buffer */ 181 for (len = bufrem, off = 0; ; len += bufrem) { 182 /* Make sure there is room for more data */ 183 grep_lnbufgrow(len + LNBUFBUMP); 184 grep_copyline(off, len - off); 185 off = len; 186 if (grep_refill(f) != 0) 187 goto error; 188 if (bufrem == 0) 189 /* EOF: return partial line */ 190 break; 191 if ((p = memchr(bufpos, line_sep, bufrem)) == NULL) 192 continue; 193 /* got it: finish up the line (like code above) */ 194 ++p; 195 diff = p - bufpos; 196 len += diff; 197 grep_lnbufgrow(len + 1); 198 grep_copyline(off, diff); 199 bufrem -= diff; 200 bufpos = p; 201 break; 202 } 203 *lenp = len; 204 return ((char *)lnbuf); 205 206 error: 207 *lenp = 0; 208 return (NULL); 209 } 210 211 static inline struct file * 212 grep_file_init(struct file *f) 213 { 214 215 #ifndef WITHOUT_GZIP 216 if (filebehave == FILE_GZIP && 217 (gzbufdesc = gzdopen(f->fd, "r")) == NULL) 218 goto error; 219 #endif 220 221 #ifndef WITHOUT_BZ2 222 if (filebehave == FILE_BZIP && 223 (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL) 224 goto error; 225 #endif 226 227 /* Fill read buffer, also catches errors early */ 228 if (grep_refill(f) != 0) 229 goto error; 230 231 /* Check for binary stuff, if necessary */ 232 if (!nulldataflag && binbehave != BINFILE_TEXT && 233 memchr(bufpos, '\0', bufrem) != NULL) 234 f->binary = true; 235 236 return (f); 237 error: 238 close(f->fd); 239 free(f); 240 return (NULL); 241 } 242 243 /* 244 * Opens a file for processing. 245 */ 246 struct file * 247 grep_open(const char *path) 248 { 249 struct file *f; 250 251 f = grep_malloc(sizeof *f); 252 memset(f, 0, sizeof *f); 253 if (path == NULL) { 254 /* Processing stdin implies --line-buffered. */ 255 lbflag = true; 256 f->fd = STDIN_FILENO; 257 } else if ((f->fd = open(path, O_RDONLY)) == -1) { 258 free(f); 259 return (NULL); 260 } 261 262 return (grep_file_init(f)); 263 } 264 265 /* 266 * Closes a file. 267 */ 268 void 269 grep_close(struct file *f) 270 { 271 272 close(f->fd); 273 274 /* Reset read buffer and line buffer */ 275 bufpos = buffer; 276 bufrem = 0; 277 278 free(lnbuf); 279 lnbuf = NULL; 280 lnbuflen = 0; 281 } 282
Indexes created Wed Sep 24 02:09:48 GMT 2025