Add hsearch and hsearch_r. Consolidate all functions prototyped in

search.h in one directory.

9 files changed, 334 insertions, 93 deletions

diff --git a/libc/misc/Makefile b/libc/misc/Makefile
index 2a74a4e54..46de813da 100644
--- a/libc/misc/Makefile
+++ b/libc/misc/Makefile
@@ -25,9 +25,9 @@ TOPDIR=../../
 include $(TOPDIR)Rules.mak
 
 
-DIRS = assert ctype dirent file fnmatch glob internals lsearch \
-       mntent syslog time utmp tsearch locale sysvipc statfs \
-       error insremque ttyent gnu
+DIRS = assert ctype dirent file fnmatch glob internals \
+       mntent syslog time utmp locale sysvipc statfs \
+       error ttyent gnu search
 ifeq ($(strip $(UCLIBC_HAS_REGEX)),y)
 DIRS += regex
 endif
diff --git a/libc/misc/insremque/Makefile b/libc/misc/insremque/Makefile
deleted file mode 100644
index c8d82dc91..000000000
--- a/libc/misc/insremque/Makefile
+++ /dev/null
@@ -1,43 +0,0 @@
-# Makefile for uClibc
-#
-# Copyright (C) 2000 by Lineo, inc.
-#
-# This program is free software; you can redistribute it and/or modify it under
-# the terms of the GNU Library General Public License as published by the Free
-# Software Foundation; either version 2 of the License, or (at your option) any
-# later version.
-#
-# This program 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 Library General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Library General Public License
-# along with this program; if not, write to the Free Software Foundation, Inc.,
-# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-#
-# Derived in part from the Linux-8086 C library, the GNU C Library, and several
-# other sundry sources.  Files within this library are copyright by their
-# respective copyright holders.
-
-TOPDIR=../../../
-include $(TOPDIR)Rules.mak
-
-CSRC=insremque.c
-COBJS=$(patsubst %.c,%.o, $(CSRC))
-OBJS=$(COBJS)
-
-all: $(OBJS) $(LIBC)
-
-$(LIBC): ar-target
-
-ar-target: $(OBJS)
-	$(AR) $(ARFLAGS) $(LIBC) $(OBJS)
-
-$(COBJS): %.o : %.c
-	$(CC) $(CFLAGS) -c $< -o $@
-	$(STRIPTOOL) -x -R .note -R .comment $*.o
-
-clean:
-	rm -f *.[oa] *~ core
-
diff --git a/libc/misc/lsearch/Makefile b/libc/misc/search/Makefile
index 69475c960..38046a455 100644
--- a/libc/misc/lsearch/Makefile
+++ b/libc/misc/search/Makefile
@@ -24,16 +24,44 @@
 TOPDIR=../../../
 include $(TOPDIR)Rules.mak
 
-CSRC=lsearch.c
+MSRC1=tsearch.c
+MOBJ1=tsearch.o tfind.o tdelete.o twalk.o
+
+MSRC2=lsearch.c
+MOBJ2=lfind.o lsearch.o
+
+MSRC3=insremque.c
+MOBJ3=insque.o remque.o
+
+MSRC4=hsearch_r.c
+MOBJ4=hcreate_r.o hdestroy_r.o hsearch_r.o
+
+CSRC=hsearch.c
 COBJS=$(patsubst %.c,%.o, $(CSRC))
 OBJS=$(COBJS)
 
-all: $(OBJS) $(LIBC)
+all: $(MOBJ1) $(MOBJ2) $(MOBJ3) $(MOBJ4) $(OBJS) $(LIBC)
 
 $(LIBC): ar-target
 
-ar-target: $(OBJS)
-	$(AR) $(ARFLAGS) $(LIBC) $(OBJS)
+ar-target: $(MOBJ)
+	$(AR) $(ARFLAGS) $(LIBC) $(MOBJ)
+
+$(MOBJ1): $(MSRC1)
+	$(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
+	$(STRIPTOOL) -x -R .note -R .comment $*.o
+
+$(MOBJ2): $(MSRC2)
+	$(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
+	$(STRIPTOOL) -x -R .note -R .comment $*.o
+
+$(MOBJ3): $(MSRC3)
+	$(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
+	$(STRIPTOOL) -x -R .note -R .comment $*.o
+
+$(MOBJ4): $(MSRC4)
+	$(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
+	$(STRIPTOOL) -x -R .note -R .comment $*.o
 
 $(COBJS): %.o : %.c
 	$(CC) $(CFLAGS) -c $< -o $@
diff --git a/libc/misc/search/hsearch.c b/libc/misc/search/hsearch.c
new file mode 100644
index 000000000..067e4973b
--- /dev/null
+++ b/libc/misc/search/hsearch.c
@@ -0,0 +1,56 @@
+/* Copyright (C) 1993, 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
+   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>
+   This file is part of the GNU C Library.
+
+   The GNU C Library 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.
+
+   The GNU C Library 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 the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <search.h>
+
+/* The non-reentrant version use a global space for storing the table.  */
+static struct hsearch_data htab;
+
+
+/* Define the non-reentrant function using the reentrant counterparts.  */
+ENTRY *hsearch (ENTRY item, ACTION action)
+{
+  ENTRY *result;
+
+  (void) hsearch_r (item, action, &result, &htab);
+
+  return result;
+}
+
+
+int hcreate (size_t nel)
+{
+  return hcreate_r (nel, &htab);
+}
+
+
+/* void __hdestroy (void) */
+void hdestroy (void)
+{
+  hdestroy_r (&htab);
+}
+/* weak_alias (__hdestroy, hdestroy) */
+
+/* Make sure the table is freed if we want to free everything before
+   exiting.  */
+/* text_set_element (__libc_subfreeres, __hdestroy); */
diff --git a/libc/misc/search/hsearch_r.c b/libc/misc/search/hsearch_r.c
new file mode 100644
index 000000000..10efb1a88
--- /dev/null
+++ b/libc/misc/search/hsearch_r.c
@@ -0,0 +1,228 @@
+/* Copyright (C) 1993, 1995, 1996, 1997, 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1993.
+
+   The GNU C Library 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.
+
+   The GNU C Library 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 the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <errno.h>
+#include <malloc.h>
+#include <string.h>
+
+#include <search.h>
+
+/* [Aho,Sethi,Ullman] Compilers: Principles, Techniques and Tools, 1986
+   [Knuth]            The Art of Computer Programming, part 3 (6.4)  */
+
+
+/* The reentrant version has no static variables to maintain the state.
+   Instead the interface of all functions is extended to take an argument
+   which describes the current status.  */
+typedef struct _ENTRY
+{
+  unsigned int used;
+  ENTRY entry;
+}
+_ENTRY;
+
+
+#ifdef L_hcreate_r
+
+/* For the used double hash method the table size has to be a prime. To
+   correct the user given table size we need a prime test.  This trivial
+   algorithm is adequate because
+   a)  the code is (most probably) called a few times per program run and
+   b)  the number is small because the table must fit in the core  */
+static int isprime (unsigned int number)
+{
+  /* no even number will be passed */
+  unsigned int div = 3;
+
+  while (div * div < number && number % div != 0)
+    div += 2;
+
+  return number % div != 0;
+}
+
+
+/* Before using the hash table we must allocate memory for it.
+   Test for an existing table are done. We allocate one element
+   more as the found prime number says. This is done for more effective
+   indexing as explained in the comment for the hsearch function.
+   The contents of the table is zeroed, especially the field used
+   becomes zero.  */
+int hcreate_r (size_t nel, struct hsearch_data *htab)
+{
+  /* Test for correct arguments.  */
+  if (htab == NULL)
+    {
+      __set_errno (EINVAL);
+      return 0;
+    }
+
+  /* There is still another table active. Return with error. */
+  if (htab->table != NULL)
+    return 0;
+
+  /* Change nel to the first prime number not smaller as nel. */
+  nel |= 1;      /* make odd */
+  while (!isprime (nel))
+    nel += 2;
+
+  htab->size = nel;
+  htab->filled = 0;
+
+  /* allocate memory and zero out */
+  htab->table = (_ENTRY *) calloc (htab->size + 1, sizeof (_ENTRY));
+  if (htab->table == NULL)
+    return 0;
+
+  /* everything went alright */
+  return 1;
+}
+/* libc_hidden_def (hcreate_r) */
+#endif
+
+#ifdef L_hdestroy_r
+/* After using the hash table it has to be destroyed. The used memory can
+   be freed and the local static variable can be marked as not used.  */
+void hdestroy_r (struct hsearch_data *htab)
+{
+  /* Test for correct arguments.  */
+  if (htab == NULL)
+    {
+      __set_errno (EINVAL);
+      return;
+    }
+
+  if (htab->table != NULL)
+    /* free used memory */
+    free (htab->table);
+
+  /* the sign for an existing table is an value != NULL in htable */
+  htab->table = NULL;
+}
+/* libc_hidden_def (hdestroy_r) */
+#endif
+
+#ifdef L_hsearch_r
+/* This is the search function. It uses double hashing with open addressing.
+   The argument item.key has to be a pointer to an zero terminated, most
+   probably strings of chars. The function for generating a number of the
+   strings is simple but fast. It can be replaced by a more complex function
+   like ajw (see [Aho,Sethi,Ullman]) if the needs are shown.
+
+   We use an trick to speed up the lookup. The table is created by hcreate
+   with one more element available. This enables us to use the index zero
+   special. This index will never be used because we store the first hash
+   index in the field used where zero means not used. Every other value
+   means used. The used field can be used as a first fast comparison for
+   equality of the stored and the parameter value. This helps to prevent
+   unnecessary expensive calls of strcmp.  */
+int hsearch_r (ENTRY item, ACTION action, ENTRY **retval,
+	       struct hsearch_data *htab)
+{
+  unsigned int hval;
+  unsigned int count;
+  unsigned int len = strlen (item.key);
+  unsigned int idx;
+
+  /* Compute an value for the given string. Perhaps use a better method. */
+  hval = len;
+  count = len;
+  while (count-- > 0)
+    {
+      hval <<= 4;
+      hval += item.key[count];
+    }
+
+  /* First hash function: simply take the modul but prevent zero. */
+  hval %= htab->size;
+  if (hval == 0)
+    ++hval;
+
+  /* The first index tried. */
+  idx = hval;
+
+  if (htab->table[idx].used)
+    {
+      /* Further action might be required according to the action value. */
+      unsigned hval2;
+
+      if (htab->table[idx].used == hval
+	  && strcmp (item.key, htab->table[idx].entry.key) == 0)
+	{
+	  *retval = &htab->table[idx].entry;
+	  return 1;
+	}
+
+      /* Second hash function, as suggested in [Knuth] */
+      hval2 = 1 + hval % (htab->size - 2);
+
+      do
+	{
+	  /* Because SIZE is prime this guarantees to step through all
+             available indeces.  */
+          if (idx <= hval2)
+	    idx = htab->size + idx - hval2;
+	  else
+	    idx -= hval2;
+
+	  /* If we visited all entries leave the loop unsuccessfully.  */
+	  if (idx == hval)
+	    break;
+
+            /* If entry is found use it. */
+          if (htab->table[idx].used == hval
+	      && strcmp (item.key, htab->table[idx].entry.key) == 0)
+	    {
+	      *retval = &htab->table[idx].entry;
+	      return 1;
+	    }
+	}
+      while (htab->table[idx].used);
+    }
+
+  /* An empty bucket has been found. */
+  if (action == ENTER)
+    {
+      /* If table is full and another entry should be entered return
+	 with error.  */
+      if (action == ENTER && htab->filled == htab->size)
+	{
+	  __set_errno (ENOMEM);
+	  *retval = NULL;
+	  return 0;
+	}
+
+      htab->table[idx].used  = hval;
+      htab->table[idx].entry = item;
+
+      ++htab->filled;
+
+      *retval = &htab->table[idx].entry;
+      return 1;
+    }
+
+  __set_errno (ESRCH);
+  *retval = NULL;
+  return 0;
+}
+/* libc_hidden_def (hsearch_r) */
+#endif
diff --git a/libc/misc/insremque/insremque.c b/libc/misc/search/insremque.c
index 7f156c601..29e547ff3 100644
--- a/libc/misc/insremque/insremque.c
+++ b/libc/misc/search/insremque.c
@@ -24,6 +24,8 @@
 #endif
 #include <search.h>
 
+#ifdef L_insque
+
 /* Insert ELEM into a doubly-linked list, after PREV.  */
 
 void
@@ -37,6 +39,9 @@ insque (void *elem, void *prev)
   ((struct qelem *) elem)->q_back = (struct qelem *) prev;
 }
 
+#endif
+
+#ifdef L_remque
 /* Unlink ELEM from the doubly-linked list that it is in.  */
 
 void
@@ -49,3 +54,5 @@ remque (void *elem)
   if (prev != NULL)
     prev->q_forw = (struct qelem *) next;
 }
+
+#endif
diff --git a/libc/misc/lsearch/lsearch.c b/libc/misc/search/lsearch.c
index 8b10fd874..2a9996d47 100644
--- a/libc/misc/lsearch/lsearch.c
+++ b/libc/misc/search/lsearch.c
@@ -12,6 +12,8 @@
 #include <stdio.h>
 #include <search.h>
 
+#ifdef L_lfind
+
 void *lfind(const void *key, const void *base, size_t *nmemb,
 	size_t size, int (*compar)(const void *, const void *))
 {
@@ -25,6 +27,10 @@ void *lfind(const void *key, const void *base, size_t *nmemb,
 	return (NULL);
 }
 
+#endif
+
+#ifdef L_lsearch
+
 void *lsearch(const void *key, void *base, size_t *nmemb, 
 	size_t size, int (*compar)(const void *, const void *))
 {
@@ -36,3 +42,5 @@ void *lsearch(const void *key, void *base, size_t *nmemb,
 	}
 	return (p);
 }
+
+#endif
diff --git a/libc/misc/tsearch/tsearch.c b/libc/misc/search/tsearch.c
index b584e2f15..b584e2f15 100644
--- a/libc/misc/tsearch/tsearch.c
+++ b/libc/misc/search/tsearch.c
diff --git a/libc/misc/tsearch/Makefile b/libc/misc/tsearch/Makefile
deleted file mode 100644
index 5f10c4026..000000000
--- a/libc/misc/tsearch/Makefile
+++ /dev/null
@@ -1,43 +0,0 @@
-# Makefile for uClibc
-#
-# Copyright (C) 2000 by Lineo, inc.
-# Copyright (C) 2000,2001 Erik Andersen <andersen@uclibc.org>
-#
-# This program is free software; you can redistribute it and/or modify it under
-# the terms of the GNU Library General Public License as published by the Free
-# Software Foundation; either version 2 of the License, or (at your option) any
-# later version.
-#
-# This program 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 Library General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Library General Public License
-# along with this program; if not, write to the Free Software Foundation, Inc.,
-# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-#
-# Derived in part from the Linux-8086 C library, the GNU C Library, and several
-# other sundry sources.  Files within this library are copyright by their
-# respective copyright holders.
-
-TOPDIR=../../../
-include $(TOPDIR)Rules.mak
-
-MSRC=tsearch.c
-MOBJ=tsearch.o tfind.o tdelete.o twalk.o
-
-all: $(MOBJ) $(LIBC)
-
-$(LIBC): ar-target
-
-ar-target: $(MOBJ)
-	$(AR) $(ARFLAGS) $(LIBC) $(MOBJ)
-
-$(MOBJ): $(MSRC)
-	$(CC) $(CFLAGS) -DL_$* $< -c -o $*.o
-	$(STRIPTOOL) -x -R .note -R .comment $*.o
-
-clean:
-	rm -f *.[oa] *~ core
-