[PATCH 07/11] libiberty, include, libctf: Use bsearch_r to avoid nonportable __thread

[Nick Alcock <nick dot alcock at oracle dot com>]

We do not AC_LIBOBJ bsearch_r at this point because as far as I can see
this obvious function is not implemented by anyone's libc.  We can
easily move it to AC_LIBOBJ later if it proves necessary.

	PR25120
include/
	* libiberty.h (bsearch_r): New.
libiberty/
	* bsearch_r.c: New file.
	* Makefile.in (CFILES): Add bsearch_r.c.
	(REQUIRED_OFILES): Add bsearch_r.o.
	(bsearch_r.$(objext)): New target.
libctf/
	* ctf-archive.c (search_nametbl): No longer global: declare...
	(ctf_arc_open_by_name_internal): ... here. Use bsearch_r.
	(search_modent_by_name): Take and use ARG for the nametbl.
---
 include/ChangeLog     |  5 +++
 include/libiberty.h   |  7 ++++
 libctf/ChangeLog      |  7 ++++
 libctf/ctf-archive.c  | 17 ++++----
 libiberty/ChangeLog   |  8 ++++
 libiberty/Makefile.in | 12 +++++-
 libiberty/bsearch_r.c | 92 +++++++++++++++++++++++++++++++++++++++++++
 7 files changed, 138 insertions(+), 10 deletions(-)
 create mode 100644 libiberty/bsearch_r.c

diff --git a/include/ChangeLog b/include/ChangeLog
index 03f4d626b1..a84047c4bf 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,8 @@
+2019-12-16  Nick Alcock  <nick.alcock@oracle.com>
+
+	PR libctf/25120
+	* libiberty.h (bsearch_r): New.
+
 2019-12-16  Nick Alcock  <nick.alcock@oracle.com>
 
 	* ctf-api.h (ctf_arc_bufopen): New.
diff --git a/include/libiberty.h b/include/libiberty.h
index 5747613502..4376e61f99 100644
--- a/include/libiberty.h
+++ b/include/libiberty.h
@@ -637,6 +637,13 @@ extern int pexecute (const char *, char * const *, const char *,
 
 extern int pwait (int, int *, int);
 
+/* Like bsearch, but takes and passes on an argument like qsort_r.  */
+
+extern void *bsearch_r (register const void *, const void *,
+			size_t, register size_t,
+			register int (*)(const void *, const void *, void *),
+			void *);
+
 #if defined(HAVE_DECL_ASPRINTF) && !HAVE_DECL_ASPRINTF
 /* Like sprintf but provides a pointer to malloc'd storage, which must
    be freed by the caller.  */
diff --git a/libctf/ChangeLog b/libctf/ChangeLog
index 3f536cee86..7b0e9e6fa7 100644
--- a/libctf/ChangeLog
+++ b/libctf/ChangeLog
@@ -1,3 +1,10 @@
+2019-12-16  Nick Alcock  <nick.alcock@oracle.com>
+
+	PR libctf/25120
+	* ctf-archive.c (search_nametbl): No longer global: declare...
+	(ctf_arc_open_by_name_internal): ... here. Use bsearch_r.
+	(search_modent_by_name): Take and use ARG for the nametbl.
+
 2019-12-16  Nick Alcock  <nick.alcock@oracle.com>
 
 	* ctf-impl.h (ctf_new_archive_internal): Declare.
diff --git a/libctf/ctf-archive.c b/libctf/ctf-archive.c
index bf3e32f128..050fe390e6 100644
--- a/libctf/ctf-archive.c
+++ b/libctf/ctf-archive.c
@@ -44,9 +44,6 @@ static int arc_mmap_writeout (int fd, void *header, size_t headersz,
 			      const char **errmsg);
 static int arc_mmap_unmap (void *header, size_t headersz, const char **errmsg);
 
-/* bsearch() internal state.  */
-static __thread char *search_nametbl;
-
 /* Write out a CTF archive to the start of the file referenced by the passed-in
    fd.  The entries in CTF_FILES are referenced by name: the names are passed in
    the names array, which must have CTF_FILES entries.
@@ -332,13 +329,14 @@ sort_modent_by_name (const void *one, const void *two, void *n)
 		 &nametbl[le64toh (b->name_offset)]);
 }
 
-/* bsearch() function to search for a given name in the sorted array of struct
+/* bsearch_r() function to search for a given name in the sorted array of struct
    ctf_archive_modents.  */
 static int
-search_modent_by_name (const void *key, const void *ent)
+search_modent_by_name (const void *key, const void *ent, void *arg)
 {
   const char *k = key;
   const struct ctf_archive_modent *v = ent;
+  const char *search_nametbl = arg;
 
   return strcmp (k, &search_nametbl[le64toh (v->name_offset)]);
 }
@@ -503,6 +501,7 @@ ctf_arc_open_by_name_internal (const struct ctf_archive *arc,
 			       const char *name, int *errp)
 {
   struct ctf_archive_modent *modent;
+  const char *search_nametbl;
 
   if (name == NULL)
     name = _CTF_SECTION;		 /* The default name.  */
@@ -512,10 +511,10 @@ ctf_arc_open_by_name_internal (const struct ctf_archive *arc,
   modent = (ctf_archive_modent_t *) ((char *) arc
 				     + sizeof (struct ctf_archive));
 
-  search_nametbl = (char *) arc + le64toh (arc->ctfa_names);
-  modent = bsearch (name, modent, le64toh (arc->ctfa_nfiles),
-		    sizeof (struct ctf_archive_modent),
-		    search_modent_by_name);
+  search_nametbl = (const char *) arc + le64toh (arc->ctfa_names);
+  modent = bsearch_r (name, modent, le64toh (arc->ctfa_nfiles),
+		      sizeof (struct ctf_archive_modent),
+		      search_modent_by_name, (void *) search_nametbl);
 
   /* This is actually a common case and normal operation: no error
      debug output.  */
diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index 95cb1525f2..6b6d47f7b5 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -1,3 +1,11 @@
+2019-12-16  Nick Alcock  <nick.alcock@oracle.com>
+
+	PR libctf/25120
+	* bsearch_r.c: New file.
+	* Makefile.in (CFILES): Add bsearch_r.c.
+	(REQUIRED_OFILES): Add bsearch_r.o.
+	(bsearch_r.$(objext)): New target.
+
 2019-08-08  Martin Liska  <mliska@suse.cz>
 
 	PR bootstrap/91352
diff --git a/libiberty/Makefile.in b/libiberty/Makefile.in
index 0be45b4ae8..f14a6e1455 100644
--- a/libiberty/Makefile.in
+++ b/libiberty/Makefile.in
@@ -123,7 +123,7 @@ COMPILE.c = $(CC) -c @DEFS@ $(CFLAGS) $(CPPFLAGS) -I. -I$(INCDIR) \
 # CONFIGURED_OFILES and funcs in configure.ac.  Also run "make maint-deps"
 # to build the new rules.
 CFILES = alloca.c argv.c asprintf.c atexit.c				\
-	basename.c bcmp.c bcopy.c bsearch.c bzero.c			\
+	basename.c bcmp.c bcopy.c bsearch.c bsearch_r.c bzero.c		\
 	calloc.c choose-temp.c clock.c concat.c cp-demangle.c		\
 	 cp-demint.c cplus-dem.c crc32.c				\
 	d-demangle.c dwarfnames.c dyn-string.c				\
@@ -167,6 +167,7 @@ REQUIRED_OFILES =							\
 	./regex.$(objext) ./cplus-dem.$(objext) ./cp-demangle.$(objext) \
 	./md5.$(objext) ./sha1.$(objext) ./alloca.$(objext)		\
 	./argv.$(objext)						\
+	./bsearch_r.$(objext)						\
 	./choose-temp.$(objext) ./concat.$(objext)			\
 	./cp-demint.$(objext) ./crc32.$(objext) ./d-demangle.$(objext)	\
 	./dwarfnames.$(objext) ./dyn-string.$(objext)			\
@@ -597,6 +598,15 @@ $(CONFIGURED_OFILES): stamp-picdir stamp-noasandir
 	else true; fi
 	$(COMPILE.c) $(srcdir)/bsearch.c $(OUTPUT_OPTION)
 
+./bsearch_r.$(objext): $(srcdir)/bsearch_r.c config.h $(INCDIR)/ansidecl.h
+	if [ x"$(PICFLAG)" != x ]; then \
+	  $(COMPILE.c) $(PICFLAG) $(srcdir)/bsearch_r.c -o pic/$@; \
+	else true; fi
+	if [ x"$(NOASANFLAG)" != x ]; then \
+	  $(COMPILE.c) $(PICFLAG) $(NOASANFLAG) $(srcdir)/bsearch_r.c -o noasan/$@; \
+	else true; fi
+	$(COMPILE.c) $(srcdir)/bsearch_r.c $(OUTPUT_OPTION)
+
 ./bzero.$(objext): $(srcdir)/bzero.c
 	if [ x"$(PICFLAG)" != x ]; then \
 	  $(COMPILE.c) $(PICFLAG) $(srcdir)/bzero.c -o pic/$@; \
diff --git a/libiberty/bsearch_r.c b/libiberty/bsearch_r.c
new file mode 100644
index 0000000000..467631e44e
--- /dev/null
+++ b/libiberty/bsearch_r.c
@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 1990 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. [rescinded 22 July 1999]
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/*
+
+@deftypefn Supplemental void* bsearch_r (const void *@var{key}, @
+  const void *@var{base}, size_t @var{nmemb}, size_t @var{size}, @
+  int (*@var{compar})(const void *, const void *, void *), void *@var{arg})
+
+Performs a search over an array of @var{nmemb} elements pointed to by
+@var{base} for a member that matches the object pointed to by @var{key}.
+The size of each member is specified by @var{size}.  The array contents
+should be sorted in ascending order according to the @var{compar}
+comparison function.  This routine should take two arguments pointing to
+the @var{key} and to an array member, in that order, and should return an
+integer less than, equal to, or greater than zero if the @var{key} object
+is respectively less than, matching, or greater than the array member.
+
+@end deftypefn
+
+*/
+
+#include "config.h"
+#include "ansidecl.h"
+#include <sys/types.h>		/* size_t */
+#include <stdio.h>
+
+/*
+ * Perform a binary search.
+ *
+ * The code below is a bit sneaky.  After a comparison fails, we
+ * divide the work in half by moving either left or right. If lim
+ * is odd, moving left simply involves halving lim: e.g., when lim
+ * is 5 we look at item 2, so we change lim to 2 so that we will
+ * look at items 0 & 1.  If lim is even, the same applies.  If lim
+ * is odd, moving right again involes halving lim, this time moving
+ * the base up one item past p: e.g., when lim is 5 we change base
+ * to item 3 and make lim 2 so that we will look at items 3 and 4.
+ * If lim is even, however, we have to shrink it by one before
+ * halving: e.g., when lim is 4, we still looked at item 2, so we
+ * have to make lim 3, then halve, obtaining 1, so that we will only
+ * look at item 3.
+ */
+void *
+bsearch_r (register const void *key, const void *base0,
+	   size_t nmemb, register size_t size,
+	   register int (*compar)(const void *, const void *, void *),
+	   void *arg)
+{
+	register const char *base = (const char *) base0;
+	register int lim, cmp;
+	register const void *p;
+
+	for (lim = nmemb; lim != 0; lim >>= 1) {
+		p = base + (lim >> 1) * size;
+		cmp = (*compar)(key, p, arg);
+		if (cmp == 0)
+			return (void *)p;
+		if (cmp > 0) {	/* key > p: move right */
+			base = (const char *)p + size;
+			lim--;
+		} /* else move left */
+	}
+	return (NULL);
+}
-- 
2.24.1.242.gb57e918ca5