Cached the current working directory to avoid needless calls to the

unix getcwd. It is put here, so that the call to get_wd() in options.c
will cause the cache to fill BEFORE the heap and constant spaces get
allocated. This way it is much more likely that the fork that getcwd
tries to do will be successful.

diff --git a/v7/src/microcode/uxenv.c b/v7/src/microcode/uxenv.c
index ddb92eb70b2556bf442132af7438ab8a66efe326..4f2269698a5047bd0e456613402fd795cfc5225e 100644 (file)
--- a/v7/src/microcode/uxenv.c
+++ b/v7/src/microcode/uxenv.c
@@ -1,6 +1,6 @@
 /* -*-C-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/microcode/uxenv.c,v 1.5 1991/07/31 14:37:20 jinx Exp $
+$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/microcode/uxenv.c,v 1.6 1991/10/08 21:46:43 markf Exp $
 
 Copyright (c) 1990-91 Massachusetts Institute of Technology
 
@@ -265,32 +265,37 @@ DEFUN_VOID (UX_initialize_environment)
 #endif
 }
 \f
+static size_t current_dir_path_size = 0;
+static char * current_dir_path = 0;
+
 CONST char *
 DEFUN_VOID (OS_working_dir_pathname)
 {
-  static size_t path_size = 0;
-  static char * path;
-  if (path_size == 0)
+  if (current_dir_path) {
+    return (current_dir_path);
+  }
+  if (current_dir_path_size == 0)
     {
-      path = (UX_malloc (1024));
-      if (path == 0)
+      current_dir_path = (UX_malloc (1024));
+      if (current_dir_path == 0)
        error_system_call (ENOMEM, syscall_malloc);
-      path_size = 1024;
+      current_dir_path_size = 1024;
     }
   while (1)
     {
-      if ((UX_getcwd (path, path_size)) != 0)
-       return (path);
+      if ((UX_getcwd (current_dir_path, current_dir_path_size)) != 0)
+       return (current_dir_path);
       if (errno != ERANGE)
        error_system_call (errno, syscall_getcwd);
-      path_size *= 2;
+      current_dir_path_size *= 2;
       {
-       char * new_path = (UX_realloc (path, path_size));
-       if (new_path == 0)
+       char * new_current_dir_path =
+         (UX_realloc (current_dir_path, current_dir_path_size));
+       if (new_current_dir_path == 0)
          /* ANSI C requires `path' to be unchanged -- we may have to
             discard it for systems that don't behave thus. */
          error_system_call (ENOMEM, syscall_realloc);
-       path = new_path;
+       current_dir_path = new_current_dir_path;
       }
     }
 }
@@ -298,7 +303,22 @@ DEFUN_VOID (OS_working_dir_pathname)
 void
 DEFUN (OS_set_working_dir_pathname, (name), CONST char * name)
 {
+  size_t name_size = strlen (name);
   STD_VOID_SYSTEM_CALL (syscall_chdir, (UX_chdir (name)));
+  while (1) {
+    if (name_size < current_dir_path_size) {
+      strcpy(current_dir_path, name);
+      return;
+    } 
+    current_dir_path_size *= 2;
+    {
+      char * new_current_dir_path =
+       (UX_realloc (current_dir_path, current_dir_path_size));
+      if (new_current_dir_path == 0)
+       error_system_call (ENOMEM, syscall_realloc);
+      current_dir_path = new_current_dir_path;
+    }
+  }
 }
 
 CONST char *