xref: /netbsd-src/lib/libc/hash/hashhl.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /* $NetBSD: hashhl.c,v 1.4 2010/01/17 23:10:20 wiz Exp $ */
2 
3 /*
4  * ----------------------------------------------------------------------------
5  * "THE BEER-WARE LICENSE" (Revision 42):
6  * <phk@login.dkuug.dk> wrote this file.  As long as you retain this notice you
7  * can do whatever you want with this stuff. If we meet some day, and you think
8  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
9  * ----------------------------------------------------------------------------
10  */
11 
12 /*
13  * Modified September 24, 2005 by Elad Efrat <elad@NetBSD.org>
14  * Modified April 29, 1997 by Jason R. Thorpe <thorpej@NetBSD.org>
15  */
16 
17 #ifdef HASH_ALGORITHM
18 
19 #if HAVE_NBTOOL_CONFIG_H
20 #include "nbtool_config.h"
21 #endif
22 
23 /*
24  * Do all the name mangling before we include "namespace.h"
25  */
26 #define	CONCAT(x,y)	__CONCAT(x,y)
27 
28 #ifndef HASH_FNPREFIX
29 #define	HASH_FNPREFIX	HASH_ALGORITHM
30 #endif /* !HASH_FNPREFIX */
31 
32 #define	FNPREFIX(x)	CONCAT(HASH_FNPREFIX,x)
33 #define	HASH_CTX	CONCAT(HASH_ALGORITHM,_CTX)
34 #define	HASH_LEN	CONCAT(HASH_ALGORITHM,_DIGEST_LENGTH)
35 #define	HASH_STRLEN	CONCAT(HASH_ALGORITHM,_DIGEST_STRING_LENGTH)
36 
37 #if !defined(_KERNEL) && defined(__weak_alias) && !defined(HAVE_NBTOOL_CONFIG_H)
38 #define	WA(a,b)	__weak_alias(a,b)
39 WA(FNPREFIX(End),CONCAT(_,FNPREFIX(End)))
40 WA(FNPREFIX(FileChunk),CONCAT(_,FNPREFIX(FileChunk)))
41 WA(FNPREFIX(File),CONCAT(_,FNPREFIX(File)))
42 WA(FNPREFIX(Data),CONCAT(_,FNPREFIX(Data)))
43 #undef WA
44 #endif
45 
46 #include "namespace.h"
47 #include HASH_INCLUDE
48 
49 #include <sys/types.h>
50 #include <sys/stat.h>
51 
52 #include <assert.h>
53 #include <fcntl.h>
54 #include <errno.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <unistd.h>
58 
59 #ifndef MIN
60 #define	MIN(x,y)	((x)<(y)?(x):(y))
61 #endif /* !MIN */
62 
63 
64 char *
65 FNPREFIX(End)(HASH_CTX *ctx, char *buf)
66 {
67 	int i;
68 	unsigned char digest[HASH_LEN];
69 	static const char hex[]="0123456789abcdef";
70 
71 	_DIAGASSERT(ctx != 0);
72 
73 	if (buf == NULL)
74 		buf = malloc((size_t)HASH_STRLEN);
75 	if (buf == NULL)
76 		return (NULL);
77 
78 	FNPREFIX(Final)(digest, ctx);
79 
80 	for (i = 0; i < HASH_LEN; i++) {
81 		buf[i+i] = hex[(u_int32_t)digest[i] >> 4];
82 		buf[i+i+1] = hex[digest[i] & 0x0f];
83 	}
84 
85 	buf[i+i] = '\0';
86 	return (buf);
87 }
88 
89 char *
90 FNPREFIX(FileChunk)(const char *filename, char *buf, off_t off, off_t len)
91 {
92 	struct stat sb;
93 	u_char buffer[BUFSIZ];
94 	HASH_CTX ctx;
95 	int fd, save_errno;
96 	ssize_t nr;
97 
98 	FNPREFIX(Init)(&ctx);
99 
100 	if ((fd = open(filename, O_RDONLY)) < 0)
101 		return (NULL);
102 	if (len == 0) {
103 		if (fstat(fd, &sb) == -1) {
104 			close(fd);
105 			return (NULL);
106 		}
107 		len = sb.st_size;
108 	}
109 	if (off > 0 && lseek(fd, off, SEEK_SET) < 0) {
110 		close(fd);
111 		return (NULL);
112 	}
113 
114 	while ((nr = read(fd, buffer, (size_t) MIN((off_t)sizeof(buffer), len)))
115 	    > 0) {
116 		FNPREFIX(Update)(&ctx, buffer, (unsigned int)nr);
117 		if (len > 0 && (len -= nr) == 0)
118 			break;
119 	}
120 
121 	save_errno = errno;
122 	close(fd);
123 	errno = save_errno;
124 	return (nr < 0 ? NULL : FNPREFIX(End)(&ctx, buf));
125 }
126 
127 char *
128 FNPREFIX(File)(const char *filename, char *buf)
129 {
130 	return (FNPREFIX(FileChunk)(filename, buf, (off_t)0, (off_t)0));
131 }
132 
133 char *
134 FNPREFIX(Data)(const unsigned char *data, size_t len, char *buf)
135 {
136 	HASH_CTX ctx;
137 
138 	_DIAGASSERT(data != 0);
139 
140 	FNPREFIX(Init)(&ctx);
141 	FNPREFIX(Update)(&ctx, data, (unsigned int)len);
142 	return (FNPREFIX(End)(&ctx, buf));
143 }
144 
145 #endif /* HASH_ALGORITHM */
146