1 /* $NetBSD: file.c,v 1.5 2011/02/16 18:35:39 joerg Exp $ */ 2 /* $FreeBSD$ */ 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 Coïdan Smørgrav 7 * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org> 8 * Copyright (C) 2010 Dimitry Andric <dimitry@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 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/mman.h> 38 #include <sys/stat.h> 39 #include <sys/types.h> 40 41 #include <err.h> 42 #include <errno.h> 43 #include <fcntl.h> 44 #include <stddef.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <unistd.h> 48 #include <wchar.h> 49 #include <wctype.h> 50 #include <zlib.h> 51 52 #ifndef WITHOUT_LZMA 53 #include <lzma.h> 54 #endif 55 56 #ifndef WITHOUT_BZIP2 57 #include <bzlib.h> 58 #endif 59 60 #include "grep.h" 61 62 #define MAXBUFSIZ (32 * 1024) 63 #define LNBUFBUMP 80 64 65 static gzFile gzbufdesc; 66 #ifndef WITHOUT_LZMA 67 static lzma_stream lstrm = LZMA_STREAM_INIT; 68 static lzma_action laction; 69 static uint8_t lin_buf[MAXBUFSIZ]; 70 #endif 71 #ifndef WITHOUT_BZIP2 72 static BZFILE* bzbufdesc; 73 #endif 74 75 static unsigned char *buffer; 76 static unsigned char *bufpos; 77 static size_t bufrem; 78 static size_t fsiz; 79 80 static unsigned char *lnbuf; 81 static size_t lnbuflen; 82 83 static inline int 84 grep_refill(struct file *f) 85 { 86 ssize_t nr; 87 88 if (filebehave == FILE_MMAP) 89 return (0); 90 91 bufpos = buffer; 92 bufrem = 0; 93 94 if (filebehave == FILE_GZIP) { 95 nr = gzread(gzbufdesc, buffer, MAXBUFSIZ); 96 #ifndef WITHOUT_BZIP2 97 } else if (filebehave == FILE_BZIP && bzbufdesc != NULL) { 98 int bzerr; 99 100 nr = BZ2_bzRead(&bzerr, bzbufdesc, buffer, MAXBUFSIZ); 101 switch (bzerr) { 102 case BZ_OK: 103 case BZ_STREAM_END: 104 /* No problem, nr will be okay */ 105 break; 106 case BZ_DATA_ERROR_MAGIC: 107 /* 108 * As opposed to gzread(), which simply returns the 109 * plain file data, if it is not in the correct 110 * compressed format, BZ2_bzRead() instead aborts. 111 * 112 * So, just restart at the beginning of the file again, 113 * and use plain reads from now on. 114 */ 115 BZ2_bzReadClose(&bzerr, bzbufdesc); 116 bzbufdesc = NULL; 117 if (lseek(f->fd, 0, SEEK_SET) == -1) 118 return (-1); 119 nr = read(f->fd, buffer, MAXBUFSIZ); 120 break; 121 default: 122 /* Make sure we exit with an error */ 123 nr = -1; 124 } 125 #endif 126 #ifndef WITHOUT_LZMA 127 } else if ((filebehave == FILE_XZ) || (filebehave == FILE_LZMA)) { 128 lzma_ret ret; 129 lstrm.next_out = buffer; 130 131 do { 132 if (lstrm.avail_in == 0) { 133 lstrm.next_in = lin_buf; 134 nr = read(f->fd, lin_buf, MAXBUFSIZ); 135 136 if (nr < 0) 137 return (-1); 138 else if (nr == 0) 139 laction = LZMA_FINISH; 140 141 lstrm.avail_in = nr; 142 } 143 144 ret = lzma_code(&lstrm, laction); 145 146 if (ret != LZMA_OK && ret != LZMA_STREAM_END) 147 return (-1); 148 149 if (lstrm.avail_out == 0 || ret == LZMA_STREAM_END) { 150 bufrem = MAXBUFSIZ - lstrm.avail_out; 151 lstrm.next_out = buffer; 152 lstrm.avail_out = MAXBUFSIZ; 153 } 154 } while (bufrem == 0 && ret != LZMA_STREAM_END); 155 156 return (0); 157 #endif /* WIHTOUT_LZMA */ 158 } else 159 nr = read(f->fd, buffer, MAXBUFSIZ); 160 161 if (nr < 0) 162 return (-1); 163 164 bufrem = nr; 165 return (0); 166 } 167 168 static inline int 169 grep_lnbufgrow(size_t newlen) 170 { 171 172 if (lnbuflen < newlen) { 173 lnbuf = grep_realloc(lnbuf, newlen); 174 lnbuflen = newlen; 175 } 176 177 return (0); 178 } 179 180 char * 181 grep_fgetln(struct file *f, size_t *lenp) 182 { 183 unsigned char *p; 184 char *ret; 185 size_t len; 186 size_t off; 187 ptrdiff_t diff; 188 189 /* Fill the buffer, if necessary */ 190 if (bufrem == 0 && grep_refill(f) != 0) 191 goto error; 192 193 if (bufrem == 0) { 194 /* Return zero length to indicate EOF */ 195 *lenp = 0; 196 return (bufpos); 197 } 198 199 /* Look for a newline in the remaining part of the buffer */ 200 if ((p = memchr(bufpos, '\n', bufrem)) != NULL) { 201 ++p; /* advance over newline */ 202 ret = bufpos; 203 len = p - bufpos; 204 bufrem -= len; 205 bufpos = p; 206 *lenp = len; 207 return (ret); 208 } 209 210 /* We have to copy the current buffered data to the line buffer */ 211 for (len = bufrem, off = 0; ; len += bufrem) { 212 /* Make sure there is room for more data */ 213 if (grep_lnbufgrow(len + LNBUFBUMP)) 214 goto error; 215 memcpy(lnbuf + off, bufpos, len - off); 216 off = len; 217 if (grep_refill(f) != 0) 218 goto error; 219 if (bufrem == 0) 220 /* EOF: return partial line */ 221 break; 222 if ((p = memchr(bufpos, '\n', bufrem)) == NULL) 223 continue; 224 /* got it: finish up the line (like code above) */ 225 ++p; 226 diff = p - bufpos; 227 len += diff; 228 if (grep_lnbufgrow(len)) 229 goto error; 230 memcpy(lnbuf + off, bufpos, diff); 231 bufrem -= diff; 232 bufpos = p; 233 break; 234 } 235 *lenp = len; 236 return (lnbuf); 237 238 error: 239 *lenp = 0; 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 goto error1; 259 260 if (filebehave == FILE_MMAP) { 261 struct stat st; 262 263 if ((fstat(f->fd, &st) == -1) || (st.st_size > OFF_MAX) || 264 (!S_ISREG(st.st_mode))) 265 filebehave = FILE_STDIO; 266 else { 267 int flags = MAP_PRIVATE | MAP_NOCORE | MAP_NOSYNC; 268 #ifdef MAP_PREFAULT_READ 269 flags |= MAP_PREFAULT_READ; 270 #endif 271 fsiz = st.st_size; 272 buffer = mmap(NULL, fsiz, PROT_READ, flags, 273 f->fd, (off_t)0); 274 if (buffer == MAP_FAILED) 275 filebehave = FILE_STDIO; 276 else { 277 bufrem = st.st_size; 278 bufpos = buffer; 279 madvise(buffer, st.st_size, MADV_SEQUENTIAL); 280 } 281 } 282 } 283 284 if ((buffer == NULL) || (buffer == MAP_FAILED)) 285 buffer = grep_malloc(MAXBUFSIZ); 286 287 if (filebehave == FILE_GZIP && 288 (gzbufdesc = gzdopen(f->fd, "r")) == NULL) 289 goto error2; 290 291 #ifndef WITHOUT_BZIP2 292 if (filebehave == FILE_BZIP && 293 (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL) 294 goto error2; 295 #endif 296 #ifndef WITHOUT_LZMA 297 else if ((filebehave == FILE_XZ) || (filebehave == FILE_LZMA)) { 298 lzma_ret ret; 299 300 ret = (filebehave == FILE_XZ) ? 301 lzma_stream_decoder(&lstrm, UINT64_MAX, 302 LZMA_CONCATENATED) : 303 lzma_alone_decoder(&lstrm, UINT64_MAX); 304 305 if (ret != LZMA_OK) 306 goto error2; 307 308 lstrm.avail_in = 0; 309 lstrm.avail_out = MAXBUFSIZ; 310 laction = LZMA_RUN; 311 } 312 #endif 313 314 /* Fill read buffer, also catches errors early */ 315 if (bufrem == 0 && grep_refill(f) != 0) 316 goto error2; 317 318 /* Check for binary stuff, if necessary */ 319 if (binbehave != BINFILE_TEXT && memchr(bufpos, '\0', bufrem) != NULL) 320 f->binary = true; 321 322 return (f); 323 324 error2: 325 close(f->fd); 326 error1: 327 free(f); 328 return (NULL); 329 } 330 331 /* 332 * Closes a file. 333 */ 334 void 335 grep_close(struct file *f) 336 { 337 338 close(f->fd); 339 340 /* Reset read buffer and line buffer */ 341 if (filebehave == FILE_MMAP) { 342 munmap(buffer, fsiz); 343 buffer = NULL; 344 } 345 bufpos = buffer; 346 bufrem = 0; 347 348 free(lnbuf); 349 lnbuf = NULL; 350 lnbuflen = 0; 351 } 352