usr.bin/grep/binary.c

   1 /*      $NetBSD: binary.c,v 1.2 2004/10/30 17:37:09 dsl Exp $   */
   2
   3 /*-
   4  * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
   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
  30 #include <sys/cdefs.h>
  31 #ifndef lint
  32 __RCSID("$NetBSD: binary.c,v 1.2 2004/10/30 17:37:09 dsl Exp $");
  33 #endif /* not lint */
  34
  35 #include <ctype.h>
  36 #include <stdio.h>
  37 #include <zlib.h>
  38
  39 #include "grep.h"
  40
  41 #define BUFFER_SIZE 128
  42
  43 static inline int
  44 okchar(unsigned char c)
  45 {
  46         return isprint(c) || isspace(c) || c == line_endchar;
  47 }
  48
  49 int
  50 bin_file(FILE *f)
  51 {
  52         unsigned char buf[BUFFER_SIZE];
  53         size_t i, m;
  54
  55         if (fseek(f, 0L, SEEK_SET) == -1)
  56                 return 0;
  57
  58         if ((m = fread(buf, 1, BUFFER_SIZE, f)) == 0)
  59                 return 0;
  60
  61         for (i = 0; i < m; i++)
  62                 if (!okchar(buf[i]))
  63                         return 1;
  64
  65         rewind(f);
  66         return 0;
  67 }
  68
  69 int
  70 gzbin_file(gzFile *f)
  71 {
  72         unsigned char buf[BUFFER_SIZE];
  73         int i, m;
  74
  75         if (gzseek(f, 0L, SEEK_SET) == -1)
  76                 return 0;
  77
  78         if ((m = gzread(f, buf, BUFFER_SIZE)) <= 0)
  79                 return 0;
  80
  81         for (i = 0; i < m; i++)
  82                 if (!okchar(buf[i]))
  83                         return 1;
  84
  85         gzrewind(f);
  86         return 0;
  87 }
  88
  89 int
  90 mmbin_file(mmf_t *f)
  91 {
  92         size_t i;
  93         /* XXX knows too much about mmf internals */
  94         for (i = 0; i < BUFFER_SIZE && i < f->len; i++)
  95                 if (!okchar(f->base[i]))
  96                         return 1;
  97         mmrewind(f);
  98         return 0;
  99 }