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-rw-r--r--lib/fnv/fnv32.c467
1 files changed, 467 insertions, 0 deletions
diff --git a/lib/fnv/fnv32.c b/lib/fnv/fnv32.c
new file mode 100644
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--- /dev/null
+++ b/lib/fnv/fnv32.c
@@ -0,0 +1,467 @@
+/*
+ * fnv32 - 32 bit Fowler/Noll/Vo hash of a buffer or string
+ *
+ * @(#) $Revision: 5.5 $
+ * @(#) $Id: fnv32.c,v 5.5 2012/03/21 01:38:12 chongo Exp $
+ * @(#) $Source: /usr/local/src/cmd/fnv/RCS/fnv32.c,v $
+ *
+ ***
+ *
+ * Fowler/Noll/Vo hash
+ *
+ * The basis of this hash algorithm was taken from an idea sent
+ * as reviewer comments to the IEEE POSIX P1003.2 committee by:
+ *
+ * Phong Vo (http://www.research.att.com/info/kpv/)
+ * Glenn Fowler (http://www.research.att.com/~gsf/)
+ *
+ * In a subsequent ballot round:
+ *
+ * Landon Curt Noll (http://www.isthe.com/chongo/)
+ *
+ * improved on their algorithm. Some people tried this hash
+ * and found that it worked rather well. In an EMail message
+ * to Landon, they named it the ``Fowler/Noll/Vo'' or FNV hash.
+ *
+ * FNV hashes are designed to be fast while maintaining a low
+ * collision rate. The FNV speed allows one to quickly hash lots
+ * of data while maintaining a reasonable collision rate. See:
+ *
+ * http://www.isthe.com/chongo/tech/comp/fnv/index.html
+ *
+ * for more details as well as other forms of the FNV hash.
+ *
+ ***
+ *
+ * Please do not copyright this code. This code is in the public domain.
+ *
+ * LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
+ * EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+ * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ *
+ * By:
+ * chongo <Landon Curt Noll> /\oo/\
+ * http://www.isthe.com/chongo/
+ *
+ * Share and Enjoy! :-)
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <string.h>
+#include "longlong.h"
+#include "fnv.h"
+
+#define WIDTH 32 /* bit width of hash */
+
+#define BUF_SIZE (32*1024) /* number of bytes to hash at a time */
+
+static char *usage =
+"usage: %s [-b bcnt] [-m] [-s arg] [-t code] [-v] [arg ...]\n"
+"\n"
+"\t-b bcnt\tmask off all but the lower bcnt bits (default 32)\n"
+"\t-m\tmultiple hashes, one per line for each arg\n"
+"\t-s\thash arg as a string (ignoring terminating NUL bytes)\n"
+"\t-t code\t test hash code: (0 ==> generate test vectors\n"
+"\t\t\t\t 1 ==> validate against FNV test vectors)\n"
+"\t-v\tverbose mode, print arg after hash (implies -m)\n"
+"\targ\tstring (if -s was given) or filename (default stdin)\n"
+"\n"
+"\tNOTE: Programs that begin with fnv0 implement the FNV-0 hash.\n"
+"\t The FNV-0 hash is historic FNV algorithm that is now deprecated.\n"
+"\n"
+"\tSee http://www.isthe.com/chongo/tech/comp/fnv/index.html for more info.\n"
+"\n"
+"\t@(#) FNV Version: %s\n";
+static char *program; /* our name */
+
+
+/*
+ * test_fnv32 - test the FNV32 hash
+ *
+ * given:
+ * hash_type type of FNV hash to test
+ * init_hval initial hash value
+ * mask lower bit mask
+ * v_flag 1 => print test failure info on stderr
+ * code 0 ==> generate FNV test vectors
+ * 1 ==> validate against FNV test vectors
+ *
+ * returns: 0 ==> OK, else test vector failure number
+ */
+static int
+test_fnv32(enum fnv_type hash_type, Fnv32_t init_hval,
+ Fnv32_t mask, int v_flag, int code)
+{
+ struct test_vector *t; /* FNV test vestor */
+ Fnv32_t hval; /* current hash value */
+ int tstnum; /* test vector that failed, starting at 1 */
+
+ /*
+ * print preamble if generating test vectors
+ */
+ if (code == 0) {
+ switch (hash_type) {
+ case FNV0_32:
+ printf("struct fnv0_32_test_vector fnv0_32_vector[] = {\n");
+ break;
+ case FNV1_32:
+ printf("struct fnv1_32_test_vector fnv1_32_vector[] = {\n");
+ break;
+ case FNV1a_32:
+ printf("struct fnv1a_32_test_vector fnv1a_32_vector[] = {\n");
+ break;
+ default:
+ unknown_hash_type(program, hash_type, 12); /* exit(12) */
+ /*NOTREACHED*/
+ }
+ }
+
+ /*
+ * loop thru all test vectors
+ */
+ for (t = fnv_test_str, tstnum = 1; t->buf != NULL; ++t, ++tstnum) {
+
+ /*
+ * compute the FNV hash
+ */
+ hval = init_hval;
+ switch (hash_type) {
+ case FNV0_32:
+ case FNV1_32:
+ hval = fnv_32_buf(t->buf, t->len, hval);
+ break;
+ case FNV1a_32:
+ hval = fnv_32a_buf(t->buf, t->len, hval);
+ break;
+ default:
+ unknown_hash_type(program, hash_type, 13); /* exit(13) */
+ /*NOTREACHED*/
+ }
+
+ /*
+ * print the vector
+ */
+ switch (code) {
+ case 0: /* generate the test vector */
+ printf(" { &fnv_test_str[%d], (Fnv32_t) 0x%08lxUL },\n",
+ tstnum-1, hval & mask);
+ break;
+ case 1: /* validate against test vector */
+ switch (hash_type) {
+ case FNV0_32:
+ if ((hval&mask) != (fnv0_32_vector[tstnum-1].fnv0_32 & mask)) {
+ if (v_flag) {
+ fprintf(stderr, "%s: failed fnv0_32 test # %d\n",
+ program, tstnum);
+ fprintf(stderr, "%s: test # 1 is 1st test\n", program);
+ fprintf(stderr,
+ "%s: expected 0x%08lx != generated: 0x%08lx\n",
+ program, (hval&mask),
+ (fnv0_32_vector[tstnum-1].fnv0_32 & mask));
+ }
+ return tstnum;
+ }
+ break;
+ case FNV1_32:
+ if ((hval&mask) != (fnv1_32_vector[tstnum-1].fnv1_32 & mask)) {
+ if (v_flag) {
+ fprintf(stderr, "%s: failed fnv1_32 test # %d\n",
+ program, tstnum);
+ fprintf(stderr, "%s: test # 1 is 1st test\n", program);
+ fprintf(stderr,
+ "%s: expected 0x%08lx != generated: 0x%08lx\n",
+ program, (hval&mask),
+ (fnv1_32_vector[tstnum-1].fnv1_32 & mask));
+ }
+ return tstnum;
+ }
+ break;
+ case FNV1a_32:
+ if ((hval&mask) != (fnv1a_32_vector[tstnum-1].fnv1a_32 &mask)) {
+ if (v_flag) {
+ fprintf(stderr, "%s: failed fnv1a_32 test # %d\n",
+ program, tstnum);
+ fprintf(stderr, "%s: test # 1 is 1st test\n", program);
+ fprintf(stderr,
+ "%s: expected 0x%08lx != generated: 0x%08lx\n",
+ program, (hval&mask),
+ (fnv1a_32_vector[tstnum-1].fnv1a_32 & mask));
+ }
+ return tstnum;
+ }
+ break;
+ }
+ break;
+ default:
+ fprintf(stderr, "%s: -m %d not implemented yet\n", program, code);
+ exit(14);
+ }
+ }
+
+ /*
+ * print completion if generating test vectors
+ */
+ if (code == 0) {
+ printf(" { NULL, 0 }\n");
+ printf("};\n");
+ }
+
+ /*
+ * no failures, return code 0 ==> all OK
+ */
+ return 0;
+}
+
+
+/*
+ * main - the main function
+ *
+ * See the above usage for details.
+ */
+int
+main(int argc, char *argv[])
+{
+ char buf[BUF_SIZE+1]; /* read buffer */
+ int readcnt; /* number of characters written */
+ Fnv32_t hval; /* current hash value */
+ int s_flag = 0; /* 1 => -s was given, hash args as strings */
+ int m_flag = 0; /* 1 => print multiple hashes, one per arg */
+ int v_flag = 0; /* 1 => verbose hash print */
+ int b_flag = WIDTH; /* -b flag value */
+ int t_flag = -1; /* FNV test vector code (0=>print, 1=>test) */
+ enum fnv_type hash_type = FNV_NONE; /* type of FNV hash to perform */
+ Fnv32_t bmask; /* mask to apply to output */
+ extern char *optarg; /* option argument */
+ extern int optind; /* argv index of the next arg */
+ int fd; /* open file to process */
+ char *p;
+ int i;
+
+ /*
+ * parse args
+ */
+ program = argv[0];
+ while ((i = getopt(argc, argv, "b:mst:v")) != -1) {
+ switch (i) {
+ case 'b': /* bcnt bit mask count */
+ b_flag = atoi(optarg);
+ break;
+ case 'm': /* print multiple hashes, one per arg */
+ m_flag = 1;
+ break;
+ case 's': /* hash args as strings */
+ s_flag = 1;
+ break;
+ case 't': /* FNV test vector code */
+ t_flag = atoi(optarg);
+ if (t_flag < 0 || t_flag > 1) {
+ fprintf(stderr, "%s: -t code must be 0 or 1\n", program);
+ fprintf(stderr, usage, program, FNV_VERSION);
+ exit(1);
+ }
+ m_flag = 1;
+ break;
+ case 'v': /* verbose hash print */
+ m_flag = 1;
+ v_flag = 1;
+ break;
+ default:
+ fprintf(stderr, usage, program, FNV_VERSION);
+ exit(1);
+ }
+ }
+ /* -t code incompatible with -b, -m and args */
+ if (t_flag >= 0) {
+ if (b_flag != WIDTH) {
+ fprintf(stderr, "%s: -t code incompatible with -b\n", program);
+ exit(2);
+ }
+ if (s_flag != 0) {
+ fprintf(stderr, "%s: -t code incompatible with -s\n", program);
+ exit(3);
+ }
+ if (optind < argc) {
+ fprintf(stderr, "%s: -t code incompatible args\n", program);
+ exit(4);
+ }
+ }
+ /* -s requires at least 1 arg */
+ if (s_flag && optind >= argc) {
+ fprintf(stderr, usage, program, FNV_VERSION);
+ exit(5);
+ }
+ /* limit -b values */
+ if (b_flag < 0 || b_flag > WIDTH) {
+ fprintf(stderr, "%s: -b bcnt: %d must be >= 0 and < %d\n",
+ program, b_flag, WIDTH);
+ exit(6);
+ }
+ if (b_flag == WIDTH) {
+ bmask = (Fnv32_t)0xffffffff;
+ } else {
+ bmask = (Fnv32_t)((1 << b_flag) - 1);
+ }
+
+ /*
+ * start with the initial basis depending on the hash type
+ */
+ p = strrchr(program, '/');
+ if (p == NULL) {
+ p = program;
+ } else {
+ ++p;
+ }
+ if (strcmp(p, "fnv032") == 0) {
+ /* using non-recommended FNV-0 and zero initial basis */
+ hval = FNV0_32_INIT;
+ hash_type = FNV0_32;
+ } else if (strcmp(p, "fnv132") == 0) {
+ /* using FNV-1 and non-zero initial basis */
+ hval = FNV1_32_INIT;
+ hash_type = FNV1_32;
+ } else if (strcmp(p, "fnv1a32") == 0) {
+ /* start with the FNV-1a initial basis */
+ hval = FNV1_32A_INIT;
+ hash_type = FNV1a_32;
+ } else {
+ fprintf(stderr, "%s: unknown program name, unknown hash type\n",
+ program);
+ exit(7);
+ }
+
+ /*
+ * FNV test vector processing, if needed
+ */
+ if (t_flag >= 0) {
+ int code; /* test vector that failed, starting at 1 */
+
+ /*
+ * perform all tests
+ */
+ code = test_fnv32(hash_type, hval, bmask, v_flag, t_flag);
+
+ /*
+ * evaluate the tests
+ */
+ if (code == 0) {
+ if (v_flag) {
+ printf("passed\n");
+ }
+ exit(0);
+ } else {
+ printf("failed vector (1 is 1st test): %d\n", code);
+ exit(8);
+ }
+ }
+
+ /*
+ * string hashing
+ */
+ if (s_flag) {
+
+ /* hash any other strings */
+ for (i=optind; i < argc; ++i) {
+ switch (hash_type) {
+ case FNV0_32:
+ case FNV1_32:
+ hval = fnv_32_str(argv[i], hval);
+ break;
+ case FNV1a_32:
+ hval = fnv_32a_str(argv[i], hval);
+ break;
+ default:
+ unknown_hash_type(program, hash_type, 9); /* exit(9) */
+ /*NOTREACHED*/
+ }
+ if (m_flag) {
+ print_fnv32(hval, bmask, v_flag, argv[i]);
+ }
+ }
+
+
+ /*
+ * file hashing
+ */
+ } else {
+
+ /*
+ * case: process only stdin
+ */
+ if (optind >= argc) {
+
+ /* case: process only stdin */
+ while ((readcnt = read(0, buf, BUF_SIZE)) > 0) {
+ switch (hash_type) {
+ case FNV0_32:
+ case FNV1_32:
+ hval = fnv_32_buf(buf, readcnt, hval);
+ break;
+ case FNV1a_32:
+ hval = fnv_32a_buf(buf, readcnt, hval);
+ break;
+ default:
+ unknown_hash_type(program, hash_type, 10); /* exit(10) */
+ /*NOTREACHED*/
+ }
+ }
+ if (m_flag) {
+ print_fnv32(hval, bmask, v_flag, "(stdin)");
+ }
+
+ } else {
+
+ /*
+ * process any other files
+ */
+ for (i=optind; i < argc; ++i) {
+
+ /* open the file */
+ fd = open(argv[i], O_RDONLY);
+ if (fd < 0) {
+ fprintf(stderr, "%s: unable to open file: %s\n",
+ program, argv[i]);
+ exit(4);
+ }
+
+ /* hash the file */
+ while ((readcnt = read(fd, buf, BUF_SIZE)) > 0) {
+ switch (hash_type) {
+ case FNV0_32:
+ case FNV1_32:
+ hval = fnv_32_buf(buf, readcnt, hval);
+ break;
+ case FNV1a_32:
+ hval = fnv_32a_buf(buf, readcnt, hval);
+ break;
+ default:
+ unknown_hash_type(program, hash_type, 11);/* exit(11) */
+ /*NOTREACHED*/
+ }
+ }
+
+ /* finish processing the file */
+ if (m_flag) {
+ print_fnv32(hval, bmask, v_flag, argv[i]);
+ }
+ close(fd);
+ }
+ }
+ }
+
+ /*
+ * report hash and exit
+ */
+ if (!m_flag) {
+ print_fnv32(hval, bmask, v_flag, "");
+ }
+ return 0; /* exit(0); */
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-25 14:51:34 +0000