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Diffstat (limited to 'src/backend/access/hash/hashfunc.c')
-rw-r--r--src/backend/access/hash/hashfunc.c411
1 files changed, 216 insertions, 195 deletions
diff --git a/src/backend/access/hash/hashfunc.c b/src/backend/access/hash/hashfunc.c
index 5862800b21d..a3cbaa1a94c 100644
--- a/src/backend/access/hash/hashfunc.c
+++ b/src/backend/access/hash/hashfunc.c
@@ -1,17 +1,17 @@
/*-------------------------------------------------------------------------
*
* hashfunc.c--
- * Comparison functions for hash access method.
+ * Comparison functions for hash access method.
*
* Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/access/hash/hashfunc.c,v 1.3 1996/11/10 02:57:40 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/access/hash/hashfunc.c,v 1.4 1997/09/07 04:37:53 momjian Exp $
*
* NOTES
- * These functions are stored in pg_amproc. For each operator class
- * defined on hash tables, they compute the hash value of the argument.
+ * These functions are stored in pg_amproc. For each operator class
+ * defined on hash tables, they compute the hash value of the argument.
*
*-------------------------------------------------------------------------
*/
@@ -20,206 +20,223 @@
#include "access/hash.h"
-uint32 hashint2(int16 key)
+uint32
+hashint2(int16 key)
{
- return ((uint32) ~key);
+ return ((uint32) ~ key);
}
-uint32 hashint4(uint32 key)
+uint32
+hashint4(uint32 key)
{
- return (~key);
+ return (~key);
}
/* Hash function from Chris Torek. */
-uint32 hashfloat4(float32 keyp)
+uint32
+hashfloat4(float32 keyp)
{
- int len;
- int loop;
- uint32 h;
- char *kp = (char *) keyp;
+ int len;
+ int loop;
+ uint32 h;
+ char *kp = (char *) keyp;
- len = sizeof(float32data);
+ len = sizeof(float32data);
-#define HASH4a h = (h << 5) - h + *kp++;
-#define HASH4b h = (h << 5) + h + *kp++;
+#define HASH4a h = (h << 5) - h + *kp++;
+#define HASH4b h = (h << 5) + h + *kp++;
#define HASH4 HASH4b
- h = 0;
- if (len > 0) {
- loop = (len + 8 - 1) >> 3;
-
- switch (len & (8 - 1)) {
- case 0:
- do { /* All fall throughs */
- HASH4;
- case 7:
- HASH4;
- case 6:
- HASH4;
- case 5:
- HASH4;
- case 4:
- HASH4;
- case 3:
- HASH4;
- case 2:
- HASH4;
- case 1:
- HASH4;
- } while (--loop);
+ h = 0;
+ if (len > 0)
+ {
+ loop = (len + 8 - 1) >> 3;
+
+ switch (len & (8 - 1))
+ {
+ case 0:
+ do
+ { /* All fall throughs */
+ HASH4;
+ case 7:
+ HASH4;
+ case 6:
+ HASH4;
+ case 5:
+ HASH4;
+ case 4:
+ HASH4;
+ case 3:
+ HASH4;
+ case 2:
+ HASH4;
+ case 1:
+ HASH4;
+ } while (--loop);
+ }
}
- }
- return (h);
-}
+ return (h);
+}
-uint32 hashfloat8(float64 keyp)
+uint32
+hashfloat8(float64 keyp)
{
- int len;
- int loop;
- uint32 h;
- char *kp = (char *) keyp;
+ int len;
+ int loop;
+ uint32 h;
+ char *kp = (char *) keyp;
- len = sizeof(float64data);
+ len = sizeof(float64data);
-#define HASH4a h = (h << 5) - h + *kp++;
-#define HASH4b h = (h << 5) + h + *kp++;
+#define HASH4a h = (h << 5) - h + *kp++;
+#define HASH4b h = (h << 5) + h + *kp++;
#define HASH4 HASH4b
- h = 0;
- if (len > 0) {
- loop = (len + 8 - 1) >> 3;
-
- switch (len & (8 - 1)) {
- case 0:
- do { /* All fall throughs */
- HASH4;
- case 7:
- HASH4;
- case 6:
- HASH4;
- case 5:
- HASH4;
- case 4:
- HASH4;
- case 3:
- HASH4;
- case 2:
- HASH4;
- case 1:
- HASH4;
- } while (--loop);
+ h = 0;
+ if (len > 0)
+ {
+ loop = (len + 8 - 1) >> 3;
+
+ switch (len & (8 - 1))
+ {
+ case 0:
+ do
+ { /* All fall throughs */
+ HASH4;
+ case 7:
+ HASH4;
+ case 6:
+ HASH4;
+ case 5:
+ HASH4;
+ case 4:
+ HASH4;
+ case 3:
+ HASH4;
+ case 2:
+ HASH4;
+ case 1:
+ HASH4;
+ } while (--loop);
+ }
}
- }
- return (h);
-}
+ return (h);
+}
-uint32 hashoid(Oid key)
+uint32
+hashoid(Oid key)
{
- return ((uint32) ~key);
+ return ((uint32) ~ key);
}
-uint32 hashchar(char key)
+uint32
+hashchar(char key)
{
- int len;
- uint32 h;
+ int len;
+ uint32 h;
+
+ len = sizeof(char);
- len = sizeof(char);
+#define PRIME1 37
+#define PRIME2 1048583
-#define PRIME1 37
-#define PRIME2 1048583
+ h = 0;
+ /* Convert char to integer */
+ h = h * PRIME1 ^ (key - ' ');
+ h %= PRIME2;
- h = 0;
- /* Convert char to integer */
- h = h * PRIME1 ^ (key - ' ');
- h %= PRIME2;
-
- return (h);
+ return (h);
}
-uint32 hashchar2(uint16 intkey)
+uint32
+hashchar2(uint16 intkey)
{
- uint32 h;
- int len;
- char *key = (char *) &intkey;
-
- h = 0;
- len = sizeof(uint16);
- /* Convert string to integer */
- while (len--)
- h = h * PRIME1 ^ (*key++ - ' ');
- h %= PRIME2;
-
- return (h);
+ uint32 h;
+ int len;
+ char *key = (char *) &intkey;
+
+ h = 0;
+ len = sizeof(uint16);
+ /* Convert string to integer */
+ while (len--)
+ h = h * PRIME1 ^ (*key++ - ' ');
+ h %= PRIME2;
+
+ return (h);
}
-uint32 hashchar4(uint32 intkey)
+uint32
+hashchar4(uint32 intkey)
{
- uint32 h;
- int len;
- char *key = (char *) &intkey;
-
- h = 0;
- len = sizeof(uint32);
- /* Convert string to integer */
- while (len--)
- h = h * PRIME1 ^ (*key++ - ' ');
- h %= PRIME2;
-
- return (h);
+ uint32 h;
+ int len;
+ char *key = (char *) &intkey;
+
+ h = 0;
+ len = sizeof(uint32);
+ /* Convert string to integer */
+ while (len--)
+ h = h * PRIME1 ^ (*key++ - ' ');
+ h %= PRIME2;
+
+ return (h);
}
-uint32 hashchar8(char *key)
+uint32
+hashchar8(char *key)
{
- uint32 h;
- int len;
-
- h = 0;
- len = sizeof(char8);
- /* Convert string to integer */
- while (len--)
- h = h * PRIME1 ^ (*key++ - ' ');
- h %= PRIME2;
-
- return (h);
+ uint32 h;
+ int len;
+
+ h = 0;
+ len = sizeof(char8);
+ /* Convert string to integer */
+ while (len--)
+ h = h * PRIME1 ^ (*key++ - ' ');
+ h %= PRIME2;
+
+ return (h);
}
-uint32 hashname(NameData *n)
+uint32
+hashname(NameData * n)
{
- uint32 h;
- int len;
- char *key;
-
- key = n->data;
-
- h = 0;
- len = NAMEDATALEN;
- /* Convert string to integer */
- while (len--)
- h = h * PRIME1 ^ (*key++ - ' ');
- h %= PRIME2;
-
- return (h);
+ uint32 h;
+ int len;
+ char *key;
+
+ key = n->data;
+
+ h = 0;
+ len = NAMEDATALEN;
+ /* Convert string to integer */
+ while (len--)
+ h = h * PRIME1 ^ (*key++ - ' ');
+ h %= PRIME2;
+
+ return (h);
}
-uint32 hashchar16(char *key)
+uint32
+hashchar16(char *key)
{
- uint32 h;
- int len;
-
- h = 0;
- len = sizeof(char16);
- /* Convert string to integer */
- while (len--)
- h = h * PRIME1 ^ (*key++ - ' ');
- h %= PRIME2;
-
- return (h);
+ uint32 h;
+ int len;
+
+ h = 0;
+ len = sizeof(char16);
+ /* Convert string to integer */
+ while (len--)
+ h = h * PRIME1 ^ (*key++ - ' ');
+ h %= PRIME2;
+
+ return (h);
}
@@ -234,45 +251,49 @@ uint32 hashchar16(char *key)
*
* "OZ's original sdbm hash"
*/
-uint32 hashtext(struct varlena *key)
+uint32
+hashtext(struct varlena * key)
{
- int keylen;
- char *keydata;
- uint32 n;
- int loop;
-
- keydata = VARDATA(key);
- keylen = VARSIZE(key);
-
- /* keylen includes the four bytes in which string keylength is stored */
- keylen -= sizeof(VARSIZE(key));
-
-#define HASHC n = *keydata++ + 65599 * n
-
- n = 0;
- if (keylen > 0) {
- loop = (keylen + 8 - 1) >> 3;
-
- switch (keylen & (8 - 1)) {
- case 0:
- do { /* All fall throughs */
- HASHC;
- case 7:
- HASHC;
- case 6:
- HASHC;
- case 5:
- HASHC;
- case 4:
- HASHC;
- case 3:
- HASHC;
- case 2:
- HASHC;
- case 1:
- HASHC;
- } while (--loop);
+ int keylen;
+ char *keydata;
+ uint32 n;
+ int loop;
+
+ keydata = VARDATA(key);
+ keylen = VARSIZE(key);
+
+ /* keylen includes the four bytes in which string keylength is stored */
+ keylen -= sizeof(VARSIZE(key));
+
+#define HASHC n = *keydata++ + 65599 * n
+
+ n = 0;
+ if (keylen > 0)
+ {
+ loop = (keylen + 8 - 1) >> 3;
+
+ switch (keylen & (8 - 1))
+ {
+ case 0:
+ do
+ { /* All fall throughs */
+ HASHC;
+ case 7:
+ HASHC;
+ case 6:
+ HASHC;
+ case 5:
+ HASHC;
+ case 4:
+ HASHC;
+ case 3:
+ HASHC;
+ case 2:
+ HASHC;
+ case 1:
+ HASHC;
+ } while (--loop);
+ }
}
- }
- return (n);
-}
+ return (n);
+}
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