New: load can search multiple directories.

* eval.c (load_search_dirs_s): New symbol variable.
(load): Initialize the name variable whose address is passed
as the third argument of open_txr_file, which is now
an in-out parameter. Pass t for the new search_dirs parameter,
so that load benefits from the searching.
(eval_init): Initialize load_search_dirs_s and register the
*load-search-dirs* special variable.

* eval.h (load_search_dirs_s): Declared.
(load_search_dirs): New macro.

* match.c (v_load): Initialize the variable passed as third argument
of open_txr_file.

* parser.c (open_txr_file): Take a new argument, search_dirs.
If this is t, it tells the function "if the path is not found,
then recurse on the *load-search-dirs* variable. Otherwise,
if the value is not t, it is a list of the remaining directories
to try. The existing parameter orig_in_resolved_out must now
point to a location which is initialized. It is assumed to hold
the original target that was passed to the load function.
The first_try_path is a the path to actually try, derived from
that one.  Thus, the caller of open_txr_file gets to determine
the initial try path using its own algorithm. Then any recursive
calls that go through *load-search-dirs* will pass a first argument
which is made of the original name, combined with a search dir.
(load_rcfile): Pass pointer to initialized location as third
argument of open-txr_file, and pass a nil value for search_dirs:
no search takes place when looking for that file, which is at a
single, fixed location.

* parser.h (open_txr_file): Declaration updated.

* txr.c (sysroot_init): Initialize *load-search-dirs*.
(txr_main): Ensure third argument in all calls to open_txr_file
points to initialized variable, with the correct value,
and pass t for the search_dirs argument.

* txr.1: Documented.

* stdlib/doc-syms.tl: Updated.
New: load can search multiple directories.

* eval.c (load_search_dirs_s): New symbol variable.
(load): Initialize the name variable whose address is passed as
the third argument of open_txr_file, which is now an in-out
parameter. Pass t for the new search_dirs parameter, so that
load benefits from the searching.
(eval_init): Initialize load_search_dirs_s and register the
*load-search-dirs* special variable.

* eval.h (load_search_dirs_s): Declared.
(load_search_dirs): New macro.

* match.c (v_load): Initialize the variable passed as third
* argument
of open_txr_file.

* parser.c (open_txr_file): Take a new argument, search_dirs.
If this is t, it tells the function "if the path is not found,
then recurse on the *load-search-dirs* variable. Otherwise, if
the value is not t, it is a list of the remaining directories
to try. The existing parameter orig_in_resolved_out must now
point to a location which is initialized. It is assumed to hold
the original target that was passed to the load function.  The
first_try_path is a the path to actually try, derived from that
one.  Thus, the caller of open_txr_file gets to determine the
initial try path using its own algorithm. Then any recursive
calls that go through *load-search-dirs* will pass a first
argument which is made of the original name, combined with a
search dir.
(load_rcfile): Pass pointer to initialized location as third
argument of open-txr_file, and pass a nil value for
search_dirs: no search takes place when looking for that file,
which is at a single, fixed location.

* parser.h (open_txr_file): Declaration updated.

* txr.c (sysroot_init): Initialize *load-search-dirs*.
(txr_main): Ensure third argument in all calls to open_txr_file
points to initialized variable, with the correct value, and
pass t for the search_dirs argument.

* txr.1: Documented.

* stdlib/doc-syms.tl: Updated.

1 files changed, 21 insertions, 5 deletions

diff --git a/parser.c b/parser.c
index 9564d276..cdfceff1 100644
--- a/parser.c
+++ b/parser.c
@@ -513,7 +513,8 @@ val parser_circ_ref(parser_t *p, val num)
 }
 
 void open_txr_file(val first_try_path, val *txr_lisp_p,
-                   val *orig_in_resolved_out, val *stream, val self)
+                   val *orig_in_resolved_out, val *stream,
+                   val search_dirs, val self)
 {
   enum { none, tl, tlo, txr } suffix;
 
@@ -599,11 +600,26 @@ void open_txr_file(val first_try_path, val *txr_lisp_p,
     }
 
     if (in == 0) {
+      val try_next;
 #ifdef ENOENT
 except:
 #endif
-      uw_ethrowf(errno_to_file_error(errno),
-                 lit("unable to open ~a"), try_path, nao);
+      if (abs_path_p(*orig_in_resolved_out))
+        search_dirs = nil;
+      else if (search_dirs == t)
+        search_dirs = load_search_dirs;
+
+#ifdef  ENOENT
+      if (errno != ENOENT || search_dirs == nil)
+#else
+      if (search_dirs == nil)
+#endif
+        uw_ethrowf(errno_to_file_error(errno),
+                   lit("~a: ~a not found"), self, *orig_in_resolved_out, nao);
+      try_next = path_cat(pop(&search_dirs), *orig_in_resolved_out);
+      open_txr_file(try_next, txr_lisp_p, orig_in_resolved_out, stream,
+                    search_dirs, self);
+      return;
     }
 
 found:
@@ -899,14 +915,14 @@ static void report_security_problem(val name)
 static void load_rcfile(val name)
 {
   val self = lit("listener");
-  val resolved_name;
+  val resolved_name = name;
   val lisp_p = t;
   val stream = nil;
   val path_private_to_me_p =  intern(lit("path-private-to-me-p"), user_package);
 
   uw_catch_begin (catch_error, sy, va);
 
-  open_txr_file(name, &lisp_p, &resolved_name, &stream, self);
+  open_txr_file(name, &lisp_p, &resolved_name, &stream, nil, self);
 
   if (stream) {
     if (!funcall1(path_private_to_me_p, stream)) {