1 /* $OpenBSD: file.c,v 1.17 2021/12/15 19:22:44 tb Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 James Howard and Dag-Erling Co�dan Sm�rgrav 5 * 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 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/stat.h> 30 #include <err.h> 31 #include <errno.h> 32 #include <fcntl.h> 33 #include <limits.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <unistd.h> 37 #include <zlib.h> 38 39 #include "grep.h" 40 41 static char fname[PATH_MAX]; 42 static char *lnbuf; 43 static size_t lnbufsize; 44 45 #define FILE_STDIO 0 46 #define FILE_MMAP 1 47 #define FILE_GZIP 2 48 49 struct file { 50 int type; 51 int noseek; 52 FILE *f; 53 mmf_t *mmf; 54 gzFile gzf; 55 }; 56 57 #ifndef NOZ 58 static char * 59 gzfgetln(gzFile f, size_t *len) 60 { 61 size_t n; 62 int c; 63 64 for (n = 0; ; ++n) { 65 c = gzgetc(f); 66 if (c == -1) { 67 const char *gzerrstr; 68 int gzerr; 69 70 if (gzeof(f)) 71 break; 72 73 gzerrstr = gzerror(f, &gzerr); 74 if (gzerr == Z_ERRNO) 75 err(2, "%s", fname); 76 else 77 errx(2, "%s: %s", fname, gzerrstr); 78 } 79 if (n >= lnbufsize) { 80 lnbufsize *= 2; 81 lnbuf = grep_realloc(lnbuf, ++lnbufsize); 82 } 83 if (c == '\n') 84 break; 85 lnbuf[n] = c; 86 } 87 88 if (gzeof(f) && n == 0) 89 return NULL; 90 *len = n; 91 return lnbuf; 92 } 93 #endif 94 95 file_t * 96 grep_fdopen(int fd) 97 { 98 file_t *f; 99 struct stat sb; 100 101 if (fd == STDIN_FILENO) 102 snprintf(fname, sizeof fname, "(standard input)"); 103 else if (fname[0] == '\0') 104 snprintf(fname, sizeof fname, "(fd %d)", fd); 105 106 if (fstat(fd, &sb) == -1) 107 return NULL; 108 if (S_ISDIR(sb.st_mode)) { 109 errno = EISDIR; 110 return NULL; 111 } 112 113 f = grep_malloc(sizeof *f); 114 115 #ifndef NOZ 116 if (Zflag) { 117 f->type = FILE_GZIP; 118 f->noseek = lseek(fd, 0L, SEEK_SET) == -1; 119 if ((f->gzf = gzdopen(fd, "r")) != NULL) 120 return f; 121 } 122 #endif 123 f->noseek = isatty(fd); 124 #ifndef SMALL 125 /* try mmap first; if it fails, try stdio */ 126 if (!f->noseek && (f->mmf = mmopen(fd, &sb)) != NULL) { 127 f->type = FILE_MMAP; 128 return f; 129 } 130 #endif 131 f->type = FILE_STDIO; 132 if ((f->f = fdopen(fd, "r")) != NULL) 133 return f; 134 135 free(f); 136 return NULL; 137 } 138 139 file_t * 140 grep_open(char *path) 141 { 142 file_t *f; 143 int fd; 144 145 snprintf(fname, sizeof fname, "%s", path); 146 147 if ((fd = open(fname, O_RDONLY)) == -1) 148 return NULL; 149 150 f = grep_fdopen(fd); 151 if (f == NULL) 152 close(fd); 153 return f; 154 } 155 156 int 157 grep_bin_file(file_t *f) 158 { 159 if (f->noseek) 160 return 0; 161 162 switch (f->type) { 163 case FILE_STDIO: 164 return bin_file(f->f); 165 #ifndef SMALL 166 case FILE_MMAP: 167 return mmbin_file(f->mmf); 168 #endif 169 #ifndef NOZ 170 case FILE_GZIP: 171 return gzbin_file(f->gzf); 172 #endif 173 default: 174 /* can't happen */ 175 errx(2, "invalid file type"); 176 } 177 } 178 179 char * 180 grep_fgetln(file_t *f, size_t *l) 181 { 182 switch (f->type) { 183 case FILE_STDIO: 184 if ((*l = getline(&lnbuf, &lnbufsize, f->f)) == -1) { 185 if (ferror(f->f)) 186 err(2, "%s: getline", fname); 187 else 188 return NULL; 189 } 190 return lnbuf; 191 #ifndef SMALL 192 case FILE_MMAP: 193 return mmfgetln(f->mmf, l); 194 #endif 195 #ifndef NOZ 196 case FILE_GZIP: 197 return gzfgetln(f->gzf, l); 198 #endif 199 default: 200 /* can't happen */ 201 errx(2, "invalid file type"); 202 } 203 } 204 205 void 206 grep_close(file_t *f) 207 { 208 switch (f->type) { 209 case FILE_STDIO: 210 fclose(f->f); 211 break; 212 #ifndef SMALL 213 case FILE_MMAP: 214 mmclose(f->mmf); 215 break; 216 #endif 217 #ifndef NOZ 218 case FILE_GZIP: 219 gzclose(f->gzf); 220 break; 221 #endif 222 default: 223 /* can't happen */ 224 errx(2, "invalid file type"); 225 } 226 free(f); 227 } 228