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hash/lookup3: spelling

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pull/8828/head
Victor Julien 1 year ago
parent 97bbc52865
commit 395f6c111d
1 changed files with 49 additions and 47 deletions
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96
src/util-hash-lookup3.c
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@ -304,14 +304,14 @@ uint32_t hashlittle( const void *key, size_t length, uint32_t initval)
}
/*----------------------------- handle the last (probably partial) block */
/*
/*
* "k[2]&0xffffff" actually reads beyond the end of the string, but
* then masks off the part it's not allowed to read. Because the
* string is aligned, the masked-off tail is in the same word as the
* rest of the string. Every machine with memory protection I've seen
* does it on word boundaries, so is OK with this. But VALGRIND will
* still catch it and complain. The masking trick does make the hash
* noticably faster for short strings (like English words).
* noticeably faster for short strings (like English words).
*/
#ifndef VALGRIND
@ -663,14 +663,14 @@ void hashlittle2(
}
/*----------------------------- handle the last (probably partial) block */
/*
/*
* "k[2]&0xffffff" actually reads beyond the end of the string, but
* then masks off the part it's not allowed to read. Because the
* string is aligned, the masked-off tail is in the same word as the
* rest of the string. Every machine with memory protection I've seen
* does it on word boundaries, so is OK with this. But VALGRIND will
* still catch it and complain. The masking trick does make the hash
* noticably faster for short strings (like English words).
* noticeably faster for short strings (like English words).
*/
#ifndef VALGRIND
@ -839,14 +839,14 @@ uint32_t hashbig( const void *key, size_t length, uint32_t initval)
}
/*----------------------------- handle the last (probably partial) block */
/*
/*
* "k[2]<<8" actually reads beyond the end of the string, but
* then shifts out the part it's not allowed to read. Because the
* string is aligned, the illegal read is in the same word as the
* rest of the string. Every machine with memory protection I've seen
* does it on word boundaries, so is OK with this. But VALGRIND will
* still catch it and complain. The masking trick does make the hash
* noticably faster for short strings (like English words).
* noticeably faster for short strings (like English words).
*/
#ifndef VALGRIND
@ -978,47 +978,49 @@ void driver2(void)
{
for (j=0; j<8; ++j) /*------------------------ for each input bit, */
{
for (m=1; m<8; ++m) /*------------ for serveral possible initvals, */
{
for (l=0; l<HASHSTATE; ++l)
e[l]=f[l]=g[l]=h[l]=x[l]=y[l]=~((uint32_t)0);
/*---- check that every output bit is affected by that input bit */
for (k=0; k<MAXPAIR; k+=2)
{
uint32_t finished=1;
/* keys have one bit different */
for (l=0; l<hlen+1; ++l) {a[l] = b[l] = (uint8_t)0;}
/* have a and b be two keys differing in only one bit */
a[i] ^= (k<<j);
a[i] ^= (k>>(8-j));
c[0] = hashlittle(a, hlen, m);
b[i] ^= ((k+1)<<j);
b[i] ^= ((k+1)>>(8-j));
d[0] = hashlittle(b, hlen, m);
/* check every bit is 1, 0, set, and not set at least once */
for (l=0; l<HASHSTATE; ++l)
{
e[l] &= (c[l]^d[l]);
f[l] &= ~(c[l]^d[l]);
g[l] &= c[l];
h[l] &= ~c[l];
x[l] &= d[l];
y[l] &= ~d[l];
if (e[l]|f[l]|g[l]|h[l]|x[l]|y[l]) finished=0;
}
if (finished) break;
}
if (k>z) z=k;
if (k==MAXPAIR)
{
printf("Some bit didn't change: ");
printf("%.8x %.8x %.8x %.8x %.8x %.8x ",
e[0],f[0],g[0],h[0],x[0],y[0]);
printf("i %d j %d m %d len %d\n", i, j, m, hlen);
}
if (z==MAXPAIR) goto done;
}
for (m = 1; m < 8; ++m) /*------------ for several possible initvals, */
{
for (l = 0; l < HASHSTATE; ++l)
e[l] = f[l] = g[l] = h[l] = x[l] = y[l] = ~((uint32_t)0);
/*---- check that every output bit is affected by that input bit */
for (k = 0; k < MAXPAIR; k += 2) {
uint32_t finished = 1;
/* keys have one bit different */
for (l = 0; l < hlen + 1; ++l) {
a[l] = b[l] = (uint8_t)0;
}
/* have a and b be two keys differing in only one bit */
a[i] ^= (k << j);
a[i] ^= (k >> (8 - j));
c[0] = hashlittle(a, hlen, m);
b[i] ^= ((k + 1) << j);
b[i] ^= ((k + 1) >> (8 - j));
d[0] = hashlittle(b, hlen, m);
/* check every bit is 1, 0, set, and not set at least once */
for (l = 0; l < HASHSTATE; ++l) {
e[l] &= (c[l] ^ d[l]);
f[l] &= ~(c[l] ^ d[l]);
g[l] &= c[l];
h[l] &= ~c[l];
x[l] &= d[l];
y[l] &= ~d[l];
if (e[l] | f[l] | g[l] | h[l] | x[l] | y[l])
finished = 0;
}
if (finished)
break;
}
if (k > z)
z = k;
if (k == MAXPAIR) {
printf("Some bit didn't change: ");
printf("%.8x %.8x %.8x %.8x %.8x %.8x ", e[0], f[0], g[0], h[0], x[0], y[0]);
printf("i %d j %d m %d len %d\n", i, j, m, hlen);
}
if (z == MAXPAIR)
goto done;
}
}
}
done:

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