xref: /netbsd-src/external/gpl2/mkhybrid/dist/libfile/lfile.c (revision 7804f23efd64308ff6bfc74397b5a25728376f71)
1 /* @(#)file.c	1.10 09/08/04 joerg */
2 #ifndef lint
3 static	const char sccsid[] =
4 	"@(#)file.c	1.10 09/08/04 joerg";
5 #endif
6 /*
7 **	find file types by using a modified "magic" file
8 **
9 **	based on file v3.22 by Ian F. Darwin (see below)
10 **
11 **	For each entry in the magic file, the message MUST start with
12 **	two 4 character strings which are the CREATOR and TYPE for the
13 **	Mac file. Any continuation lines are ignored. e.g magic entry
14 **	for a GIF file:
15 **
16 **	0       string          GIF8            8BIM GIFf
17 **	>4      string          7a              \b, version 8%s,
18 **	>4      string          9a              \b, version 8%s,
19 **	>6      leshort         >0              %hd x
20 **	>8      leshort         >0              %hd,
21 **	#>10    byte            &0x80           color mapped,
22 **	#>10    byte&0x07       =0x00           2 colors
23 **	#>10    byte&0x07       =0x01           4 colors
24 **	#>10    byte&0x07       =0x02           8 colors
25 **	#>10    byte&0x07       =0x03           16 colors
26 **	#>10    byte&0x07       =0x04           32 colors
27 **	#>10    byte&0x07       =0x05           64 colors
28 **	#>10    byte&0x07       =0x06           128 colors
29 **	#>10    byte&0x07       =0x07           256 colors
30 **
31 **	Just the "8BIM" "GIFf" will be used whatever the type GIF file
32 **	it is.
33 **
34 **	Modified for mkhybrid James Pearson 19/5/98
35 */
36 
37 /*
38  * file - find type of a file or files - main program.
39  *
40  * Copyright (c) Ian F. Darwin, 1987.
41  * Written by Ian F. Darwin.
42  *
43  * This software is not subject to any export provision of the United States
44  * Department of Commerce, and may be exported to any country or planet.
45  *
46  * Redistribution and use in source and binary forms, with or without
47  * modification, are permitted provided that the following conditions
48  * are met:
49  * 1. Redistributions of source code must retain the above copyright
50  *    notice immediately at the beginning of the file, without modification,
51  *    this list of conditions, and the following disclaimer.
52  * 2. Redistributions in binary form must reproduce the above copyright
53  *    notice, this list of conditions and the following disclaimer in the
54  *    documentation and/or other materials provided with the distribution.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
60  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  */
68 #ifndef	lint
69 static const char moduleid[] =
70 	"@(#)Id: file.c,v 1.38 1997/01/15 19:28:35 christos Exp";
71 #endif	/* lint */
72 
73 #include <stdio.h>
74 #include <stdlib.h>
75 #include <unistd.h>	/* for read() */
76 #include <sys/stat.h>
77 #include <fcntl.h>	/* for open() */
78 
79 #ifdef RESTORE_TIME
80 #include <schily/utime.h>
81 #ifdef HAVE_UTIMES
82 #define	USE_UTIMES
83 #endif
84 #endif
85 
86 #include "patchlevel.h"
87 #include "file.h"
88 
89 #ifdef MAIN
90  			/* Global command-line options 		*/
91 #ifdef DEBUG
92 int	debug = 1; 	/* debugging 				*/
93 #else
94 int	debug = 0; 	/* debugging 				*/
95 #endif /* DEBUG */
96 int	lflag = 0;	/* follow Symlinks (BSD only) 		*/
97 int	zflag = 0;	/* follow (uncompress) compressed files */
98 
99 			/* Misc globals				*/
100 char *magicfile;	/* where magic be found 		*/
101 
102 char *progname;		/* used throughout 			*/
103 #endif
104 
105 char *	get_magic_match	(const char *inname);
106 void	clean_magic	(void);
107 
108 /*
109  * get_magic_match - get the CREATOR/TYPE string
110  * based on the original process()
111  */
112 char *
get_magic_match(const char * inname)113 get_magic_match(const char *inname)
114 {
115 	int	fd = 0;
116 	unsigned char	buf[HOWMANY+1];	/* one extra for terminating '\0' */
117 	struct stat	sb;
118 	int nbytes = 0;	/* number of bytes read from a datafile */
119 	char *match;
120 
121 	/* check the file is regular and non-zero length */
122 	if (stat(inname, &sb) != 0)
123 		return 0;
124 
125 	if (sb.st_size == 0 || ! S_ISREG(sb.st_mode))
126 		return 0;
127 
128 	if ((fd = open(inname, O_RDONLY)) < 0)
129 		    return 0;
130 
131 	/*
132 	 * try looking at the first HOWMANY bytes
133 	 */
134 	if ((nbytes = read(fd, (char *)buf, HOWMANY)) == -1)
135 		return 0;
136 
137 	if (nbytes == 0)
138 		return 0;
139 	else {
140 		buf[nbytes++] = '\0';	/* null-terminate it */
141 		match = softmagic(buf, nbytes);
142 	}
143 
144 #ifdef RESTORE_TIME
145 	/* really no point as we going to access the file later anyway */
146 	{
147 		/*
148 		 * Try to restore access, modification times if read it.
149 		 */
150 # ifdef USE_UTIMES
151 		struct timeval  utsbuf[2];
152 		utsbuf[0].tv_sec = sb.st_atime;
153 		utsbuf[1].tv_sec = sb.st_mtime;
154 
155 		(void) utimes(inname, utsbuf); /* don't care if loses */
156 # else
157 		struct utimbuf  utbuf;
158 
159 		utbuf.actime = sb.st_atime;
160 		utbuf.modtime = sb.st_mtime;
161 		(void) utime(inname, &utbuf); /* don't care if loses */
162 # endif
163 	}
164 #endif
165 	(void) close(fd);
166 
167 	return(match);
168 }
169 
170 /*
171  * clean_magic - deallocate memory used
172  */
173 void
clean_magic(void)174 clean_magic(void)
175 {
176 	if (__f_magic)
177 		free(__f_magic);
178 }
179 
180 
181 #ifdef MAIN
main(int argc,char ** argv)182 main(int argc, char **argv)
183 {
184 	char	*ret;
185 	char	creator[5];
186 	char	type[5];
187 
188 	if (argc < 3)
189 		exit(1);
190 
191 	init_magic(argv[1]);
192 
193 	ret = get_magic_match(argv[2]);
194 
195 	if (!ret)
196 		ret = "unixTEXT";
197 
198 	sscanf(ret, "%4s%4s", creator, type);
199 
200 	creator[4] = type[4] = '\0';
201 
202 	printf("%s %s\n", creator, type);
203 
204 
205 	exit(0);
206 }
207 #endif /* MAIN */
208 
209