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-rw-r--r--sysdeps/gnu/Makefile5
-rw-r--r--sysdeps/gnu/eval.c138
2 files changed, 143 insertions, 0 deletions
diff --git a/sysdeps/gnu/Makefile b/sysdeps/gnu/Makefile
index 4e814d93cd..4806c0df1d 100644
--- a/sysdeps/gnu/Makefile
+++ b/sysdeps/gnu/Makefile
@@ -45,3 +45,8 @@ endif
 ifeq ($(subdir),misc)
 sysdep_headers += sys/mtio.h
 endif
+
+
+ifeq ($(subdir),dlfcn)
+libdl-routines	+= eval
+endif
diff --git a/sysdeps/gnu/eval.c b/sysdeps/gnu/eval.c
new file mode 100644
index 0000000000..ce452b722c
--- /dev/null
+++ b/sysdeps/gnu/eval.c
@@ -0,0 +1,138 @@
+/* You don't really want to know what this hack is for.
+   Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+   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 Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <dlfcn.h>
+
+static void *funcall (char **stringp);
+static void *eval (char **stringp);
+
+static void *
+funcall (char **stringp)
+{
+  void *args[strlen (*stringp)], **ap = args;
+  void *argcookie = &args[1];
+
+  do
+    {
+      /* Evaluate the next token.  */
+      *ap++ = eval (stringp);
+
+      /* Whitespace is irrelevant.  */
+      while (isspace (**stringp))
+	++*stringp;
+
+      /* Terminate at closing paren or end of line.  */
+    } while (**stringp != '\0' && **stringp != ')');
+  if (**stringp != '\0')
+    /* Swallow closing paren.  */
+    ++*stringp;
+
+  if (args[0] == NULL)
+    {
+      static const char unknown[] = "Unknown function\n";
+      write (1, unknown, sizeof unknown - 1);
+      return NULL;
+    }
+
+  /* Do it to it.  */
+  __builtin_return (__builtin_apply (args[0],
+				     &argcookie,
+				     (char *) ap - (char *) &args[1]));
+}
+
+static void *
+eval (char **stringp)
+{
+  void *value;
+  char *p = *stringp, c;
+
+  /* Whitespace is irrelevant.  */
+  while (isspace (*p))
+    ++p;
+
+  switch (*p)
+    {
+    case '"':
+      /* String constant.  */
+      value = ++p;
+      do
+	if (*p == '\\')
+	  {
+	    switch (*strcpy (p, p + 1))
+	      {
+	      case 't':
+		*p = '\t';
+		break;
+	      case 'n':
+		*p = '\n';
+		break;
+	      }
+	    ++p;
+	  }
+      while (*p != '\0' && *p++ != '"');
+      if (p[-1] == '"')
+	p[-1] = '\0';
+      break;
+
+    case '(':
+      *stringp = ++p;
+      return funcall (stringp);
+
+    default:
+      /* Try to parse it as a number.  */
+      value = (void *) strtol (p, stringp, 0);
+      if (*stringp != p)
+	return value;
+
+      /* Anything else is a symbol that produces its address.  */
+      value = p;
+      do
+	++p;
+      while (*p != '\0' && !isspace (*p) && (!ispunct (*p) || *p == '_'));
+      c = *p;
+      *p = '\0';
+      value = dlsym (NULL, value);
+      *p = c;
+      break;
+    }
+
+  *stringp = p;
+  return value;
+}
+
+
+void
+_start (void)
+{
+  char *buf = NULL;
+  size_t bufsz = 0;
+
+  while (__getdelim (&buf, &bufsz, '\n', stdin) > 0)
+    {
+      char *p = buf;
+      eval (&p);
+    }
+
+  exit (0);
+}