openwrt/tools/gnulib/patches/646-hashcode-string.patch

From 64042bb91aea5f854ca8a8938e2b3f7d1935e4f1 Mon Sep 17 00:00:00 2001
From: Bruno Haible <[email protected]>
Date: Wed, 30 Apr 2025 12:47:37 +0200
Subject: [PATCH] New module hashcode-string1.

* lib/hashcode-string1.h: New file.
* lib/hashcode-string1.c: New file, based on lib/hash.c.
* modules/hashcode-string1: New file.
* lib/hash.h: Include hashcode-string1.h.
(hash_string): Remove declaration.
* lib/hash.c (hash_string): Remove function.
* modules/hash (Depends-on): Add hashcode-string1.
* lib/exclude.c: Include hashcode-string1.h.
* modules/exclude (Depends-on): Add hashcode-string1.
---
 ChangeLog                | 13 +++++++++
 lib/exclude.c            |  1 +
 lib/hash.c               | 59 ++++++--------------------------------
 lib/hash.h               | 11 +++----
 lib/hashcode-string1.c   | 62 ++++++++++++++++++++++++++++++++++++++++
 lib/hashcode-string1.h   | 38 ++++++++++++++++++++++++
 modules/exclude          |  1 +
 modules/hash             |  1 +
 modules/hashcode-string1 | 24 ++++++++++++++++
 9 files changed, 154 insertions(+), 56 deletions(-)
 create mode 100644 lib/hashcode-string1.c
 create mode 100644 lib/hashcode-string1.h
 create mode 100644 modules/hashcode-string1

--- a/lib/exclude.c
+++ b/lib/exclude.c
@@ -36,6 +36,7 @@
 #include "filename.h"
 #include <fnmatch.h>
 #include "hash.h"
+#include "hashcode-string1.h"
 #if GNULIB_MCEL_PREFER
 # include "mcel.h"
 #else
--- a/lib/hash.c
+++ b/lib/hash.c
@@ -345,57 +345,6 @@ hash_do_for_each (const Hash_table *tabl
   return counter;
 }
 
-/* Allocation and clean-up.  */
-
-#if USE_DIFF_HASH
-
-/* About hashings, Paul Eggert writes to me (FP), on 1994-01-01: "Please see
-   B. J. McKenzie, R. Harries & T. Bell, Selecting a hashing algorithm,
-   Software--practice & experience 20, 2 (Feb 1990), 209-224.  Good hash
-   algorithms tend to be domain-specific, so what's good for [diffutils'] io.c
-   may not be good for your application."  */
-
-size_t
-hash_string (const char *string, size_t n_buckets)
-{
-# define HASH_ONE_CHAR(Value, Byte) \
-  ((Byte) + rotl_sz (Value, 7))
-
-  size_t value = 0;
-  unsigned char ch;
-
-  for (; (ch = *string); string++)
-    value = HASH_ONE_CHAR (value, ch);
-  return value % n_buckets;
-
-# undef HASH_ONE_CHAR
-}
-
-#else /* not USE_DIFF_HASH */
-
-/* This one comes from 'recode', and performs a bit better than the above as
-   per a few experiments.  It is inspired from a hashing routine found in the
-   very old Cyber 'snoop', itself written in typical Greg Mansfield style.
-   (By the way, what happened to this excellent man?  Is he still alive?)  */
-
-size_t
-hash_string (const char *string, size_t n_buckets)
-{
-  size_t value = 0;
-  unsigned char ch;
-
-  for (; (ch = *string); string++)
-    value = (value * 31 + ch) % n_buckets;
-  return value;
-}
-
-#endif /* not USE_DIFF_HASH */
-
-void
-hash_reset_tuning (Hash_tuning *tuning)
-{
-  *tuning = default_tuning;
-}
 
 /* If the user passes a NULL hasher, we hash the raw pointer.  */
 static size_t
@@ -418,6 +367,14 @@ raw_comparator (const void *a, const voi
 }
 
 
+/* Allocation and clean-up.  */
+
+void
+hash_reset_tuning (Hash_tuning *tuning)
+{
+  *tuning = default_tuning;
+}
+
 /* For the given hash TABLE, check the user supplied tuning structure for
    reasonable values, and return true if there is no gross error with it.
    Otherwise, definitively reset the TUNING field to some acceptable default
--- a/lib/hash.h
+++ b/lib/hash.h
@@ -134,11 +134,6 @@ extern size_t hash_do_for_each (const Ha
  * Allocation and clean-up.
  */
 
-/* Return a hash index for a NUL-terminated STRING between 0 and N_BUCKETS-1.
-   This is a convenience routine for constructing other hashing functions.  */
-extern size_t hash_string (const char *string, size_t n_buckets)
-       _GL_ATTRIBUTE_PURE;
-
 extern void hash_reset_tuning (Hash_tuning *tuning);
 
 typedef size_t (*Hash_hasher) (const void *entry, size_t table_size);
@@ -266,6 +261,12 @@ extern void *hash_remove (Hash_table *ta
 _GL_ATTRIBUTE_DEPRECATED
 extern void *hash_delete (Hash_table *table, const void *entry);
 
+
+# if GNULIB_HASHCODE_STRING1
+/* Include declarations of module 'hashcode-string1'.  */
+#  include "hashcode-string1.h"
+# endif
+
 # ifdef __cplusplus
 }
 # endif
--- /dev/null
+++ b/lib/hashcode-string1.c
@@ -0,0 +1,62 @@
+/* hashcode-string1.c -- compute a hash value from a NUL-terminated string.
+
+   Copyright (C) 1998-2004, 2006-2007, 2009-2025 Free Software Foundation, Inc.
+
+   This file is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   This file is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "hashcode-string1.h"
+
+#if USE_DIFF_HASH
+
+# include "bitrotate.h"
+
+/* About hashings, Paul Eggert writes to me (FP), on 1994-01-01: "Please see
+   B. J. McKenzie, R. Harries & T. Bell, Selecting a hashing algorithm,
+   Software--practice & experience 20, 2 (Feb 1990), 209-224.  Good hash
+   algorithms tend to be domain-specific, so what's good for [diffutils'] io.c
+   may not be good for your application."  */
+
+size_t
+hash_string (const char *string, size_t tablesize)
+{
+  size_t value = 0;
+  unsigned char ch;
+
+  for (; (ch = *string); string++)
+    value = ch + rotl_sz (value, 7);
+  return value % tablesize;
+}
+
+#else /* not USE_DIFF_HASH */
+
+/* This one comes from 'recode', and performs a bit better than the above as
+   per a few experiments.  It is inspired from a hashing routine found in the
+   very old Cyber 'snoop', itself written in typical Greg Mansfield style.
+   (By the way, what happened to this excellent man?  Is he still alive?)  */
+
+size_t
+hash_string (const char *string, size_t tablesize)
+{
+  size_t value = 0;
+  unsigned char ch;
+
+  for (; (ch = *string); string++)
+    value = (value * 31 + ch) % tablesize;
+  return value;
+}
+
+#endif /* not USE_DIFF_HASH */
--- /dev/null
+++ b/lib/hashcode-string1.h
@@ -0,0 +1,38 @@
+/* hashcode-string1.h -- declaration for a simple hash function
+   Copyright (C) 1998-2004, 2006-2007, 2009-2025 Free Software Foundation, Inc.
+
+   This file is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   This file is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+/* This file uses _GL_ATTRIBUTE_PURE.  */
+#if !_GL_CONFIG_H_INCLUDED
+ #error "Please include config.h first."
+#endif
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* Compute a hash code for a NUL-terminated string S,
+   and return the hash code modulo TABLESIZE.
+   The result is platform dependent: it depends on the size of the 'size_t'
+   type.  */
+extern size_t hash_string (char const *s, size_t tablesize) _GL_ATTRIBUTE_PURE;
+
+
+#ifdef __cplusplus
+}
+#endif
--- a/modules/exclude
+++ b/modules/exclude
@@ -12,6 +12,7 @@ filename
 fnmatch
 fopen-gnu
 hash
+hashcode-string1
 mbscasecmp
 mbuiter               [test "$GNULIB_MCEL_PREFER" != yes]
 nullptr
--- a/modules/hash
+++ b/modules/hash
@@ -14,6 +14,7 @@ next-prime
 bool
 stdint-h
 xalloc-oversized
+hashcode-string1
 
 configure.ac:
 
--- /dev/null
+++ b/modules/hashcode-string1
@@ -0,0 +1,24 @@
+Description:
+Compute a hash value for a NUL-terminated string.
+
+Files:
+lib/hashcode-string1.h
+lib/hashcode-string1.c
+
+Depends-on:
+bitrotate
+
+configure.ac:
+gl_MODULE_INDICATOR([hashcode-string1])
+
+Makefile.am:
+lib_SOURCES += hashcode-string1.h hashcode-string1.c
+
+Include:
+"hashcode-string1.h"
+
+License:
+LGPLv2+
+
+Maintainer:
+Jim Meyering