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file.c revision 1.1.1.1 
      1 /*-
      2  * Copyright (c) 1999 James Howard and Dag-Erling Codan Smrgrav
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  *
     14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     24  * SUCH DAMAGE.
     25  *
     26  *	$Id: file.c,v 1.1.1.1 2004/01/02 14:58:45 cjep Exp $
     27  */
     28 
     29 #include <sys/param.h>
     30 
     31 #include <err.h>
     32 #include <stdio.h>
     33 #include <stdlib.h>
     34 #include <zlib.h>
     35 
     36 #include "grep.h"
     37 
     38 static char	 fname[MAXPATHLEN];
     39 static char	*lnbuf;
     40 static int	 lnbuflen;
     41 
     42 #define FILE_STDIO	0
     43 #define FILE_MMAP	1
     44 #define FILE_GZIP	2
     45 
     46 struct file {
     47 	int	 type;
     48 	FILE	*f;
     49 	mmf_t	*mmf;
     50 	gzFile	*gzf;
     51 };
     52 
     53 static char *
     54 gzfgetln(gzFile *f, size_t *len)
     55 {
     56 	size_t		n;
     57 	int		c;
     58 
     59 	for (n = 0; ; ++n) {
     60 		c = gzgetc(f);
     61 		if (c == -1) {
     62 			const char *gzerrstr;
     63 			int gzerr;
     64 
     65 			if (gzeof(f))
     66 				break;
     67 
     68 			gzerrstr = gzerror(f, &gzerr);
     69 			if (gzerr == Z_ERRNO)
     70 				err(1, "%s", fname);
     71 			else
     72 				errx(1, "%s: %s", fname, gzerrstr);
     73 		}
     74 		if (c == '\n')
     75 			break;
     76 		if (n >= lnbuflen) {
     77 			lnbuflen *= 2;
     78 			lnbuf = grep_realloc(lnbuf, ++lnbuflen);
     79 		}
     80 		lnbuf[n] = c;
     81 	}
     82 
     83 	if (gzeof(f) && n == 0)
     84 		return NULL;
     85 	*len = n;
     86 	return lnbuf;
     87 }
     88 
     89 file_t *
     90 grep_fdopen(int fd, char *mode)
     91 {
     92 	file_t *f;
     93 
     94 	if (fd == 0)
     95 		sprintf(fname, "(standard input)");
     96 	else
     97 		sprintf(fname, "(fd %d)", fd);
     98 
     99 	f = grep_malloc(sizeof *f);
    100 
    101 	if (Zflag) {
    102 		f->type = FILE_GZIP;
    103 		if ((f->gzf = gzdopen(fd, mode)) != NULL)
    104 			return f;
    105 	} else {
    106 		f->type = FILE_STDIO;
    107 		if ((f->f = fdopen(fd, mode)) != NULL)
    108 			return f;
    109 	}
    110 
    111 	free(f);
    112 	return NULL;
    113 }
    114 
    115 file_t *
    116 grep_open(char *path, char *mode)
    117 {
    118 	file_t *f;
    119 
    120 	snprintf(fname, MAXPATHLEN, "%s", path);
    121 
    122 	f = grep_malloc(sizeof *f);
    123 
    124 	if (Zflag) {
    125 		f->type = FILE_GZIP;
    126 		if ((f->gzf = gzopen(fname, mode)) != NULL)
    127 			return f;
    128 	} else {
    129 		/* try mmap first; if it fails, try stdio */
    130 		if ((f->mmf = mmopen(fname, mode)) != NULL) {
    131 			f->type = FILE_MMAP;
    132 			return f;
    133 		}
    134 		f->type = FILE_STDIO;
    135 		if ((f->f = fopen(path, mode)) != NULL)
    136 			return f;
    137 	}
    138 
    139 	free(f);
    140 	return NULL;
    141 }
    142 
    143 int
    144 grep_bin_file(file_t *f)
    145 {
    146 	switch (f->type) {
    147 	case FILE_STDIO:
    148 		return bin_file(f->f);
    149 	case FILE_MMAP:
    150 		return mmbin_file(f->mmf);
    151 	case FILE_GZIP:
    152 		return gzbin_file(f->gzf);
    153 	default:
    154 		/* can't happen */
    155 		errx(1, "invalid file type");
    156 	}
    157 }
    158 
    159 long
    160 grep_tell(file_t *f)
    161 {
    162 	switch (f->type) {
    163 	case FILE_STDIO:
    164 		return ftell(f->f);
    165 	case FILE_MMAP:
    166 		return mmtell(f->mmf);
    167 	case FILE_GZIP:
    168 		return gztell(f->gzf);
    169 	default:
    170 		/* can't happen */
    171 		errx(1, "invalid file type");
    172 	}
    173 }
    174 
    175 char *
    176 grep_fgetln(file_t *f, size_t *l)
    177 {
    178 	switch (f->type) {
    179 	case FILE_STDIO:
    180 		return fgetln(f->f, l);
    181 	case FILE_MMAP:
    182 		return mmfgetln(f->mmf, l);
    183 	case FILE_GZIP:
    184 		return gzfgetln(f->gzf, l);
    185 	default:
    186 		/* can't happen */
    187 		errx(1, "invalid file type");
    188 	}
    189 }
    190 
    191 void
    192 grep_close(file_t *f)
    193 {
    194 	switch (f->type) {
    195 	case FILE_STDIO:
    196 		fclose(f->f);
    197 		break;
    198 	case FILE_MMAP:
    199 		mmclose(f->mmf);
    200 		break;
    201 	case FILE_GZIP:
    202 		gzclose(f->gzf);
    203 		break;
    204 	default:
    205 		/* can't happen */
    206 		errx(1, "invalid file type");
    207 	}
    208 }
    209