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 <lzma.h> 45 #include <stddef.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include <unistd.h> 49 #include <wchar.h> 50 #include <wctype.h> 51 #include <zlib.h> 52 53 #ifndef WITHOUT_BZIP2 54 #include <bzlib.h> 55 #endif 56 57 #include "grep.h" 58 59 #define MAXBUFSIZ (32 * 1024) 60 #define LNBUFBUMP 80 61 62 static gzFile gzbufdesc; 63 static lzma_stream lstrm = LZMA_STREAM_INIT; 64 #ifndef WITHOUT_BZIP2 65 static BZFILE* bzbufdesc; 66 #endif 67 68 static unsigned char *buffer; 69 static unsigned char *bufpos; 70 static size_t bufrem; 71 static size_t fsiz; 72 73 static unsigned char *lnbuf; 74 static size_t lnbuflen; 75 76 static inline int 77 grep_refill(struct file *f) 78 { 79 ssize_t nr; 80 81 if (filebehave == FILE_MMAP) 82 return (0); 83 84 bufpos = buffer; 85 bufrem = 0; 86 87 if (filebehave == FILE_GZIP) { 88 nr = gzread(gzbufdesc, buffer, MAXBUFSIZ); 89 #ifndef WITHOUT_BZIP2 90 } else if (filebehave == FILE_BZIP && bzbufdesc != NULL) { 91 int bzerr; 92 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 #endif 119 } else if ((filebehave == FILE_XZ) || (filebehave == FILE_LZMA)) { 120 lzma_action action = LZMA_RUN; 121 uint8_t in_buf[MAXBUFSIZ]; 122 lzma_ret ret; 123 124 ret = (filebehave == FILE_XZ) ? 125 lzma_stream_decoder(&lstrm, UINT64_MAX, 126 LZMA_CONCATENATED) : 127 lzma_alone_decoder(&lstrm, UINT64_MAX); 128 129 if (ret != LZMA_OK) 130 return (-1); 131 132 lstrm.next_out = buffer; 133 lstrm.avail_out = MAXBUFSIZ; 134 lstrm.next_in = in_buf; 135 nr = read(f->fd, in_buf, MAXBUFSIZ); 136 137 if (nr < 0) 138 return (-1); 139 else if (nr == 0) 140 action = LZMA_FINISH; 141 142 lstrm.avail_in = nr; 143 ret = lzma_code(&lstrm, action); 144 145 if (ret != LZMA_OK && ret != LZMA_STREAM_END) 146 return (-1); 147 bufrem = MAXBUFSIZ - lstrm.avail_out; 148 return (0); 149 } else 150 nr = read(f->fd, buffer, MAXBUFSIZ); 151 152 if (nr < 0) 153 return (-1); 154 155 bufrem = nr; 156 return (0); 157 } 158 159 static inline int 160 grep_lnbufgrow(size_t newlen) 161 { 162 163 if (lnbuflen < newlen) { 164 lnbuf = grep_realloc(lnbuf, newlen); 165 lnbuflen = newlen; 166 } 167 168 return (0); 169 } 170 171 char * 172 grep_fgetln(struct file *f, size_t *lenp) 173 { 174 unsigned char *p; 175 char *ret; 176 size_t len; 177 size_t off; 178 ptrdiff_t diff; 179 180 /* Fill the buffer, if necessary */ 181 if (bufrem == 0 && grep_refill(f) != 0) 182 goto error; 183 184 if (bufrem == 0) { 185 /* Return zero length to indicate EOF */ 186 *lenp = 0; 187 return (bufpos); 188 } 189 190 /* Look for a newline in the remaining part of the buffer */ 191 if ((p = memchr(bufpos, '\n', bufrem)) != NULL) { 192 ++p; /* advance over newline */ 193 ret = bufpos; 194 len = p - bufpos; 195 bufrem -= len; 196 bufpos = p; 197 *lenp = len; 198 return (ret); 199 } 200 201 /* We have to copy the current buffered data to the line buffer */ 202 for (len = bufrem, off = 0; ; len += bufrem) { 203 /* Make sure there is room for more data */ 204 if (grep_lnbufgrow(len + LNBUFBUMP)) 205 goto error; 206 memcpy(lnbuf + off, bufpos, len - off); 207 off = len; 208 if (grep_refill(f) != 0) 209 goto error; 210 if (bufrem == 0) 211 /* EOF: return partial line */ 212 break; 213 if ((p = memchr(bufpos, '\n', bufrem)) == NULL) 214 continue; 215 /* got it: finish up the line (like code above) */ 216 ++p; 217 diff = p - bufpos; 218 len += diff; 219 if (grep_lnbufgrow(len)) 220 goto error; 221 memcpy(lnbuf + off, bufpos, diff); 222 bufrem -= diff; 223 bufpos = p; 224 break; 225 } 226 *lenp = len; 227 return (lnbuf); 228 229 error: 230 *lenp = 0; 231 return (NULL); 232 } 233 234 /* 235 * Opens a file for processing. 236 */ 237 struct file * 238 grep_open(const char *path) 239 { 240 struct file *f; 241 242 f = grep_malloc(sizeof *f); 243 memset(f, 0, sizeof *f); 244 if (path == NULL) { 245 /* Processing stdin implies --line-buffered. */ 246 lbflag = true; 247 f->fd = STDIN_FILENO; 248 } else if ((f->fd = open(path, O_RDONLY)) == -1) 249 goto error1; 250 251 if (filebehave == FILE_MMAP) { 252 struct stat st; 253 254 if ((fstat(f->fd, &st) == -1) || (st.st_size > OFF_MAX) || 255 (!S_ISREG(st.st_mode))) 256 filebehave = FILE_STDIO; 257 else { 258 int flags = MAP_PRIVATE | MAP_NOCORE | MAP_NOSYNC; 259 #ifdef MAP_PREFAULT_READ 260 flags |= MAP_PREFAULT_READ; 261 #endif 262 fsiz = st.st_size; 263 buffer = mmap(NULL, fsiz, PROT_READ, flags, 264 f->fd, (off_t)0); 265 if (buffer == MAP_FAILED) 266 filebehave = FILE_STDIO; 267 else { 268 bufrem = st.st_size; 269 bufpos = buffer; 270 madvise(buffer, st.st_size, MADV_SEQUENTIAL); 271 } 272 } 273 } 274 275 if ((buffer == NULL) || (buffer == MAP_FAILED)) 276 buffer = grep_malloc(MAXBUFSIZ); 277 278 if (filebehave == FILE_GZIP && 279 (gzbufdesc = gzdopen(f->fd, "r")) == NULL) 280 goto error2; 281 282 #ifndef WITHOUT_BZIP2 283 if (filebehave == FILE_BZIP && 284 (bzbufdesc = BZ2_bzdopen(f->fd, "r")) == NULL) 285 goto error2; 286 #endif 287 288 /* Fill read buffer, also catches errors early */ 289 if (bufrem == 0 && grep_refill(f) != 0) 290 goto error2; 291 292 /* Check for binary stuff, if necessary */ 293 if (binbehave != BINFILE_TEXT && memchr(bufpos, '\0', bufrem) != NULL) 294 f->binary = true; 295 296 return (f); 297 298 error2: 299 close(f->fd); 300 error1: 301 free(f); 302 return (NULL); 303 } 304 305 /* 306 * Closes a file. 307 */ 308 void 309 grep_close(struct file *f) 310 { 311 312 close(f->fd); 313 314 /* Reset read buffer and line buffer */ 315 if (filebehave == FILE_MMAP) { 316 munmap(buffer, fsiz); 317 buffer = NULL; 318 } 319 bufpos = buffer; 320 bufrem = 0; 321 322 free(lnbuf); 323 lnbuf = NULL; 324 lnbuflen = 0; 325 } 326