[src/trunk]: src/usr.bin/make make: merge duplicate code for finding an entry...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5f65310cac01
branches:  trunk
changeset: 359847:5f65310cac01
user:      rillig <rillig%NetBSD.org@localhost>
date:      Thu Jan 27 11:00:07 2022 +0000

description:
make: merge duplicate code for finding an entry in a hash table

No functional change.

diffstat:

 usr.bin/make/hash.c |  59 +++++++++++++++++-----------------------------------
 1 files changed, 19 insertions(+), 40 deletions(-)

diffs (134 lines):

diff -r 7da959eedaeb -r 5f65310cac01 usr.bin/make/hash.c
--- a/usr.bin/make/hash.c       Thu Jan 27 10:45:36 2022 +0000
+++ b/usr.bin/make/hash.c       Thu Jan 27 11:00:07 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: hash.c,v 1.70 2022/01/27 10:45:36 rillig Exp $ */
+/*     $NetBSD: hash.c,v 1.71 2022/01/27 11:00:07 rillig Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -74,7 +74,7 @@
 #include "make.h"
 
 /*     "@(#)hash.c     8.1 (Berkeley) 6/6/93"  */
-MAKE_RCSID("$NetBSD: hash.c,v 1.70 2022/01/27 10:45:36 rillig Exp $");
+MAKE_RCSID("$NetBSD: hash.c,v 1.71 2022/01/27 11:00:07 rillig Exp $");
 
 /*
  * The ratio of # entries to # buckets at which we rebuild the table to
@@ -84,7 +84,7 @@
 
 /* This hash function matches Gosling's Emacs and java.lang.String. */
 static unsigned int
-Hash_String(const char *key, size_t *out_keylen)
+Hash_String(const char *key, const char **out_keyEnd)
 {
        unsigned int h;
        const char *p;
@@ -93,8 +93,7 @@
        for (p = key; *p != '\0'; p++)
                h = 31 * h + (unsigned char)*p;
 
-       if (out_keylen != NULL)
-               *out_keylen = (size_t)(p - key);
+       *out_keyEnd = p;
        return h;
 }
 
@@ -112,43 +111,22 @@
 }
 
 static HashEntry *
-HashTable_Find(HashTable *t, unsigned int h, const char *key)
+HashTable_Find(HashTable *t, Substring key, unsigned int h)
 {
        HashEntry *e;
        unsigned int chainlen = 0;
+       size_t keyLen = Substring_Length(key);
 
 #ifdef DEBUG_HASH_LOOKUP
-       DEBUG3(HASH, "HashTable_Find: %p h=%08x key=%s\n", t, h, key);
-#endif
-
-       for (e = t->buckets[h & t->bucketsMask]; e != NULL; e = e->next) {
-               chainlen++;
-               if (e->key_hash == h && strcmp(e->key, key) == 0)
-                       break;
-       }
-
-       if (chainlen > t->maxchain)
-               t->maxchain = chainlen;
-
-       return e;
-}
-
-static HashEntry *
-HashTable_FindEntryBySubstring(HashTable *t, Substring key, unsigned int h)
-{
-       HashEntry *e;
-       unsigned int chainlen = 0;
-
-#ifdef DEBUG_HASH_LOOKUP
-       DEBUG4(HASH, "HashTable_FindEntryBySubstring: %p h=%08x key=%.*s\n",
-           t, h, (int)Substring_Length(key), key.start);
+       DEBUG4(HASH, "HashTable_Find: %p h=%08x key=%.*s\n",
+           t, h, (int)keyLen, key.start);
 #endif
 
        for (e = t->buckets[h & t->bucketsMask]; e != NULL; e = e->next) {
                chainlen++;
                if (e->key_hash == h &&
-                   strncmp(e->key, key.start, Substring_Length(key)) == 0 &&
-                   e->key[Substring_Length(key)] == '\0')
+                   strncmp(e->key, key.start, keyLen) == 0 &&
+                   e->key[keyLen] == '\0')
                        break;
        }
 
@@ -203,8 +181,9 @@
 HashEntry *
 HashTable_FindEntry(HashTable *t, const char *key)
 {
-       unsigned int h = Hash_String(key, NULL);
-       return HashTable_Find(t, h, key);
+       const char *keyEnd;
+       unsigned int h = Hash_String(key, &keyEnd);
+       return HashTable_Find(t, Substring_Init(key, keyEnd), h);
 }
 
 /* Find the value corresponding to the key, or return NULL. */
@@ -222,7 +201,7 @@
 void *
 HashTable_FindValueBySubstringHash(HashTable *t, Substring key, unsigned int h)
 {
-       HashEntry *he = HashTable_FindEntryBySubstring(t, key, h);
+       HashEntry *he = HashTable_Find(t, key, h);
        return he != NULL ? he->value : NULL;
 }
 
@@ -270,9 +249,9 @@
 HashEntry *
 HashTable_CreateEntry(HashTable *t, const char *key, bool *out_isNew)
 {
-       size_t keylen;
-       unsigned int h = Hash_String(key, &keylen);
-       HashEntry *he = HashTable_Find(t, h, key);
+       const char *keyEnd;
+       unsigned int h = Hash_String(key, &keyEnd);
+       HashEntry *he = HashTable_Find(t, Substring_Init(key, keyEnd), h);
 
        if (he != NULL) {
                if (out_isNew != NULL)
@@ -283,10 +262,10 @@
        if (t->numEntries >= rebuildLimit * t->bucketsSize)
                HashTable_Enlarge(t);
 
-       he = bmake_malloc(sizeof *he + keylen);
+       he = bmake_malloc(sizeof *he + (size_t)(keyEnd - key));
        he->value = NULL;
        he->key_hash = h;
-       memcpy(he->key, key, keylen + 1);
+       memcpy(he->key, key, (size_t)(keyEnd - key) + 1);
 
        he->next = t->buckets[h & t->bucketsMask];
        t->buckets[h & t->bucketsMask] = he;