rpcgen - fall back to looking for cpp in system path

Fall back to the system cpp when /lib/cpp is not present. Removes
searching for /usr/ccs/lib/cpp which is not supported on any system that
uses glibc.

ChangeLog

@@ -1,3 +1,12 @@
+2012-08-07	Allan McRae	<allan@archlinux.org>
+
+	[BZ #14303]
+	* sunrpc/rpc_main.c (SVR4_CPP): Remove.
+	(SUNOS_CPP): Likewise.
+	(find_cpp): Fall back to selecting system cpp when /lib/cpp is
+	not found.
+	(open_input): Call CPP using execvp.
+
 2012-08-07  Joseph Myers  <joseph@codesourcery.com>
 
 	* sysdeps/unix/sysv/linux/kernel-features.h

sunrpc/rpc_main.c

@@ -75,12 +75,9 @@ struct commandline
 
 static const char *cmdname;
 
-#define SVR4_CPP "/usr/ccs/lib/cpp"
-#define SUNOS_CPP "/lib/cpp"
-
 static const char *svcclosetime = "120";
 static int cppDefined;	/* explicit path for C preprocessor */
-static const char *CPP = SUNOS_CPP;
+static const char *CPP = "/lib/cpp";
 static const char CPPFLAGS[] = "-C";
 static char *pathbuf;
 static int cpp_pid;
@@ -327,23 +324,17 @@ find_cpp (void)
 {
   struct stat buf;
 
-  if (stat (CPP, &buf) < 0)
-    {				/* /lib/cpp or explicit cpp does not exist */
-      if (cppDefined)
-	{
-	  fprintf (stderr, _ ("cannot find C preprocessor: %s \n"), CPP);
-	  crash ();
-	}
-      else
-	{			/* try the other one */
-	  CPP = SVR4_CPP;
-	  if (stat (CPP, &buf) < 0)
-	    {			/* can't find any cpp */
-	      fputs (_ ("cannot find any C preprocessor (cpp)\n"), stdout);
-	      crash ();
-	    }
-	}
+  if (stat (CPP, &buf) == 0)
+    return;
+
+  if (cppDefined) /* user specified cpp but it does not exist */
+    {
+      fprintf (stderr, _ ("cannot find C preprocessor: %s\n"), CPP);
+      crash ();
     }
+
+  /* fall back to system CPP */
+  CPP = "cpp";
 }
 
 /*
@@ -374,8 +365,13 @@ open_input (const char *infile, const char *define)
       close (1);
       dup2 (pd[1], 1);
       close (pd[0]);
-      execv (arglist[0], (char **) arglist);
-      perror ("execv");
+      execvp (arglist[0], (char **) arglist);
+      if (errno == ENOENT)
+        {
+          fprintf (stderr, _ ("cannot find C preprocessor: %s\n"), CPP);
+          exit (1);
+        }
+      perror ("execvp");
       exit (1);
     case -1:
       perror ("fork");