gen-protos/fix-header: don't use cpplib internal routines

[Zack Weinberg <zack at wolery dot cumb dot org>]

gen-protos and fix-header both use a cpplib internal routine that is
likely to disappear in the near future.  This patch corrects that.

Who owns this part of the code?

zw

	* scan.c (hashstr): New function.
	* scan.h: Prototype it.
	* gen-protos.c: Don't include cpplib.h or cpphash.h.
	Use hashstr instead of hashf.  Collect statistics on hash
	collisions.  Provide xrealloc.
	* fix-header.c: Don't include cpphash.h.  Use hashstr.
	* Makefile.in (gen-protos.o, fix-header.o): Update
	dependencies.
	(gen-protos): Don't bother linking with libcpp.a.

===================================================================
Index: scan.c
--- scan.c	1999/09/05 03:49:51	1.8
+++ scan.c	2000/01/15 23:36:08
@@ -236,3 +236,18 @@ get_token (fp, s)
   *s->ptr = 0;
   return c;
 }
+
+unsigned int
+hashstr (str, len)
+     const char *str;
+     unsigned int len;
+{
+  unsigned int n = len;
+  unsigned int r = 0;
+  const unsigned char *s = (const unsigned char *)str;
+
+  do
+    r = r * 67 + (*s++ - 113);
+  while (--n);
+  return r + len;
+}
===================================================================
Index: scan.h
--- scan.h	1999/11/03 20:40:32	1.10
+++ scan.h	2000/01/15 23:36:08
@@ -60,6 +60,7 @@ extern int read_upto _PARAMS((FILE *, ss
 extern unsigned long hash _PARAMS((const char *));
 extern void recognized_function _PARAMS((const char *, int, int, const char *, int, int, const char *, int));
 extern void recognized_extern _PARAMS((const char *, int, const char *, int));
+extern unsigned int hashstr _PARAMS((const char *, unsigned int));
 
 /* get_token is a simple C lexer. */
 #define IDENTIFIER_TOKEN 300
===================================================================
Index: gen-protos.c
--- gen-protos.c	1999/10/03 16:28:33	1.14
+++ gen-protos.c	2000/01/15 23:36:07
@@ -18,8 +18,6 @@ Foundation, 59 Temple Place - Suite 330,
 #include "hconfig.h"
 #include "system.h"
 #include "scan.h"
-#include "cpplib.h"
-#include "cpphash.h"
 #undef abort
 
 int verbose = 0;
@@ -31,6 +29,7 @@ static int parse_fn_proto	PARAMS ((char 
 #define HASH_SIZE 2503 /* a prime */
 int hash_tab[HASH_SIZE];
 int next_index;
+int collisions;
 
 static void
 add_hash (fname)
@@ -39,10 +38,11 @@ add_hash (fname)
   int i, i0;
 
   /* NOTE:  If you edit this, also edit lookup_std_proto in fix-header.c !! */
-  i = hashf (fname, strlen (fname), HASH_SIZE);
+  i = hashstr (fname, strlen (fname)) % HASH_SIZE;
   i0 = i;
   if (hash_tab[i] != 0)
     {
+      collisions++;
       for (;;)
 	{
 	  i = (i+1) % HASH_SIZE;
@@ -186,5 +186,26 @@ main (argc, argv)
     fprintf (outf, "  %d,\n", hash_tab[i]);
   fprintf (outf, "};\n");
 
+  fprintf (stderr, "gen-protos: %d entries %d collisions\n",
+	   next_index, collisions);
+  
   return 0;
+}
+
+/* Needed by scan.o.  We can't use libiberty here.  */
+PTR
+xrealloc (p, s)
+     PTR p;
+     size_t s;
+{
+  PTR r;
+  if (s == 0)
+    s = 1;
+  if (p)
+    r = realloc (p, s);
+  else
+    r = malloc (s);
+  if (!r)
+    abort ();
+  return r;
 }
===================================================================
Index: fix-header.c
--- fix-header.c	2000/01/14 17:14:43	1.32
+++ fix-header.c	2000/01/15 23:36:08
@@ -75,7 +75,6 @@ Foundation, 59 Temple Place - Suite 330,
 #include "obstack.h"
 #include "scan.h"
 #include "cpplib.h"
-#include "cpphash.h"
 
 static void v_fatal PARAMS ((const char *, va_list)) ATTRIBUTE_NORETURN;
 static void fatal PARAMS ((const char *, ...)) ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
@@ -381,7 +380,7 @@ lookup_std_proto (name, name_length)
      const char *name;
      int name_length;
 {
-  int i = hashf (name, name_length, HASH_SIZE);
+  int i = hashstr (name, name_length) % HASH_SIZE;
   int i0 = i;
   for (;;)
     {
===================================================================
Index: Makefile.in
--- Makefile.in	2000/01/14 02:01:21	1.365
+++ Makefile.in	2000/01/15 23:36:09
@@ -2232,12 +2232,12 @@ deduced.h: $(GCC_PASSES) $(srcdir)/scan-
 	  touch deduced.h; \
 	fi
 
-GEN_PROTOS_OBJS = gen-protos.o scan.o libcpp.a
+GEN_PROTOS_OBJS = gen-protos.o scan.o
 gen-protos: $(GEN_PROTOS_OBJS) $(HOST_LIBDEPS)
 	${HOST_CC} $(HOST_CFLAGS) $(HOST_LDFLAGS) -o gen-protos \
 	  $(GEN_PROTOS_OBJS) $(HOST_LIBS)
 
-gen-protos.o: gen-protos.c scan.h $(build_xm_file) system.h cpplib.h cpphash.h
+gen-protos.o: gen-protos.c scan.h $(build_xm_file) system.h
 	$(HOST_CC) -c $(HOST_CFLAGS) $(HOST_CPPFLAGS) $(INCLUDES) $(srcdir)/gen-protos.c
 
 scan.o: scan.c scan.h $(build_xm_file) system.h
@@ -2258,7 +2258,7 @@ fix-header: fix-header.o scan-decls.o sc
 	   scan-decls.o scan.o libcpp.a $(HOST_LIBS)
 
 fix-header.o: fix-header.c $(srcdir)/../include/obstack.h scan.h \
-	xsys-protos.h $(build_xm_file) system.h cpplib.h cpphash.h
+	xsys-protos.h $(build_xm_file) system.h cpplib.h
 	$(HOST_CC) -c $(HOST_CFLAGS) $(HOST_CPPFLAGS) $(INCLUDES) $(srcdir)/fix-header.c
 
 scan-decls.o: scan-decls.c scan.h cpplib.h $(build_xm_file) system.h