src/code/target-load.lisp

   1 ;;;; that part of the loader is only needed on the target system
   2 ;;;; (which is basically synonymous with "that part of the loader
   3 ;;;; which is not needed by GENESIS")
   4
   5 ;;;; This software is part of the SBCL system. See the README file for
   6 ;;;; more information.
   7 ;;;;
   8 ;;;; This software is derived from the CMU CL system, which was
   9 ;;;; written at Carnegie Mellon University and released into the
  10 ;;;; public domain. The software is in the public domain and is
  11 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
  12 ;;;; files for more information.
  13
  14 (in-package "SB!FASL")
  15
  16 (defvar *load-source-default-type* "lisp"
  17   #!+sb-doc
  18   "The source file types which LOAD looks for by default.")
  19
  20 (declaim (type (or pathname null) *load-truename* *load-pathname*))
  21 (defvar *load-truename* nil
  22   #!+sb-doc
  23   "the TRUENAME of the file that LOAD is currently loading")
  24 (defvar *load-pathname* nil
  25   #!+sb-doc
  26   "the defaulted pathname that LOAD is currently loading")
  27 \f
  28 ;;;; LOAD-AS-SOURCE
  29
  30 ;;; Load a text stream.  (Note that load-as-fasl is in another file.)
  31 (defun load-as-source (stream verbose print)
  32   (maybe-announce-load stream verbose)
  33   (macrolet ((do-sexprs ((sexpr stream) &body body)
  34                (aver (symbolp sexpr))
  35                (with-unique-names (source-info)
  36                  (once-only ((stream stream))
  37                    `(if (handler-case (pathname stream)
  38                           (error () nil))
  39                         (let ((,source-info (sb!c::make-file-source-info
  40                                             (pathname ,stream)
  41                                             (stream-external-format ,stream))))
  42                           (setf (sb!c::source-info-stream ,source-info) ,stream)
  43                           (sb!c::do-forms-from-info ((,sexpr) ,source-info)
  44                             ,@body))
  45                         (do ((,sexpr (read ,stream nil *eof-object*)
  46                                      (read ,stream nil *eof-object*)))
  47                             ((eq ,sexpr *eof-object*))
  48                           ,@body))))))
  49     (do-sexprs (sexpr stream)
  50       (if print
  51           (let ((results (multiple-value-list (eval sexpr))))
  52             (load-fresh-line)
  53             (format t "~{~S~^, ~}~%" results))
  54           (eval sexpr)))
  55     t))
  56 \f
  57 ;;;; LOAD itself
  58
  59 (define-condition fasl-header-missing (invalid-fasl)
  60   ((fhsss :reader invalid-fasl-fhsss :initarg :fhsss))
  61   (:report
  62    (lambda (condition stream)
  63      (format stream "~@<File ~S has a fasl file type, but no fasl header:~%~
  64                      Expected ~S, but got ~S.~:@>"
  65              (invalid-fasl-stream condition)
  66              (invalid-fasl-expected condition)
  67              (invalid-fasl-fhsss condition)))))
  68
  69
  70 ;;; The following comment preceded the pre 1.0.12.36 definition of
  71 ;;; LOAD; it may no longer be accurate:
  72
  73 ;; FIXME: Daniel Barlow's ilsb.tar ILISP-for-SBCL patches contain an
  74 ;; implementation of "DEFUN SOURCE-FILE" which claims, in a comment,
  75 ;; that CMU CL does not correctly record source file information when
  76 ;; LOADing a non-compiled file. Check whether this bug exists in SBCL
  77 ;; and fix it if so.
  78
  79 (defun load (pathspec &key (verbose *load-verbose*) (print *load-print*)
  80              (if-does-not-exist t) (external-format :default))
  81   #!+sb-doc
  82   "Load the file given by FILESPEC into the Lisp environment, returning
  83    T on success."
  84   (flet ((load-stream (stream)
  85            (let* (;; Bindings required by ANSI.
  86                   (*readtable* *readtable*)
  87                   (*package* (sane-package))
  88                   ;; FIXME: we should probably document the circumstances
  89                   ;; where *LOAD-PATHNAME* and *LOAD-TRUENAME* aren't
  90                   ;; pathnames during LOAD.  ANSI makes no exceptions here.
  91                   (*load-pathname* (handler-case (pathname stream)
  92                                      ;; FIXME: it should probably be a type
  93                                      ;; error to try to get a pathname for a
  94                                      ;; stream that doesn't have one, but I
  95                                      ;; don't know if we guarantee that.
  96                                      (error () nil)))
  97                   (*load-truename* (when *load-pathname*
  98                                      (handler-case (truename stream)
  99                                        (file-error () nil))))
 100                   ;; Bindings used internally.
 101                   (*load-depth* (1+ *load-depth*))
 102                   ;; KLUDGE: I can't find in the ANSI spec where it says
 103                   ;; that DECLAIM/PROCLAIM of optimization policy should
 104                   ;; have file scope. CMU CL did this, and it seems
 105                   ;; reasonable, but it might not be right; after all,
 106                   ;; things like (PROCLAIM '(TYPE ..)) don't have file
 107                   ;; scope, and I can't find anything under PROCLAIM or
 108                   ;; COMPILE-FILE or LOAD or OPTIMIZE which justifies this
 109                   ;; behavior. Hmm. -- WHN 2001-04-06
 110                   (sb!c::*policy* sb!c::*policy*))
 111              (return-from load
 112                (if (equal (stream-element-type stream) '(unsigned-byte 8))
 113                    (load-as-fasl stream verbose print)
 114                    (load-as-source stream verbose print))))))
 115     (when (streamp pathspec)
 116       (return-from load (load-stream pathspec)))
 117     (let ((pathname (pathname pathspec)))
 118       (with-open-stream
 119           (stream (or (open pathspec :element-type '(unsigned-byte 8)
 120                             :if-does-not-exist nil)
 121                       (when (null (pathname-type pathspec))
 122                         (let ((defaulted-pathname
 123                                (probe-load-defaults pathspec)))
 124                           (if defaulted-pathname
 125                               (progn (setq pathname defaulted-pathname)
 126                                      (open pathname
 127                                            :if-does-not-exist
 128                                            (if if-does-not-exist :error nil)
 129                                            :element-type '(unsigned-byte 8))))))
 130                       (if if-does-not-exist
 131                           (error 'simple-file-error
 132                                  :pathname pathspec
 133                                  :format-control
 134                                  "~@<Couldn't load ~S: file does not exist.~@:>"
 135                                  :format-arguments (list pathspec)))))
 136         (unless stream
 137           (return-from load nil))
 138
 139         (let* ((header-line (make-array
 140                              (length *fasl-header-string-start-string*)
 141                              :element-type '(unsigned-byte 8))))
 142           (read-sequence header-line stream)
 143           (if (mismatch header-line *fasl-header-string-start-string*
 144                         :test #'(lambda (code char) (= code (char-code char))))
 145               (let ((truename (probe-file stream)))
 146                 (when (and truename
 147                            (string= (pathname-type truename) *fasl-file-type*))
 148                   (error 'fasl-header-missing
 149                          :stream (namestring truename)
 150                          :fhsss header-line
 151                          :expected *fasl-header-string-start-string*)))
 152               (progn
 153                 (file-position stream :start)
 154                 (return-from load
 155                   (load-stream stream))))))
 156       (with-open-file (stream pathname :external-format external-format)
 157         (load-stream stream)))))
 158
 159 ;; This implements the defaulting SBCL seems to have inherited from
 160 ;; CMU.  This routine does not try to perform any loading; all it does
 161 ;; is return the pathname (not the truename) of a file to be loaded,
 162 ;; or NIL if no such file can be found.  This routine is supposed to
 163 ;; signal an error if a fasl's timestamp is older than its source
 164 ;; file, but we protect against errors in PROBE-FILE, because any of
 165 ;; the ways that we might fail to find a defaulted file are reasons
 166 ;; not to load it, but not worth exposing to the user who didn't
 167 ;; expicitly ask us to load a file with a made-up name (e.g., the
 168 ;; defaulted filename might exceed filename length limits).
 169 (defun probe-load-defaults (pathname)
 170   (destructuring-bind (defaulted-source-pathname
 171                        defaulted-source-truename
 172                        defaulted-fasl-pathname
 173                        defaulted-fasl-truename)
 174       (loop for type in (list *load-source-default-type*
 175                               *fasl-file-type*)
 176             as probe-pathname = (make-pathname :type type
 177                                                :defaults pathname)
 178             collect probe-pathname
 179             collect (handler-case (probe-file probe-pathname)
 180                       (file-error () nil)))
 181     (cond ((and defaulted-fasl-truename
 182                 defaulted-source-truename
 183                 (> (file-write-date defaulted-source-truename)
 184                    (file-write-date defaulted-fasl-truename)))
 185            (restart-case
 186                (error "The object file ~A is~@
 187                        older than the presumed source:~%  ~A."
 188                       defaulted-fasl-truename
 189                       defaulted-source-truename)
 190              (source () :report "load source file"
 191                      defaulted-source-pathname)
 192              (object () :report "load object file"
 193                      defaulted-fasl-pathname)))
 194           (defaulted-fasl-truename defaulted-fasl-pathname)
 195           (defaulted-source-truename defaulted-source-pathname))))
 196 \f
 197 ;;; Load a code object. BOX-NUM objects are popped off the stack for
 198 ;;; the boxed storage section, then SIZE bytes of code are read in.
 199 #!-x86
 200 (defun load-code (box-num code-length)
 201   (declare (fixnum box-num code-length))
 202   (with-fop-stack t
 203     (let ((code (%primitive sb!c:allocate-code-object box-num code-length))
 204           (index (+ sb!vm:code-trace-table-offset-slot box-num)))
 205       (declare (type index index))
 206       (setf (%code-debug-info code) (pop-stack))
 207       (dotimes (i box-num)
 208         (declare (fixnum i))
 209         (setf (code-header-ref code (decf index)) (pop-stack)))
 210       (sb!sys:without-gcing
 211         (read-n-bytes *fasl-input-stream*
 212                       (code-instructions code)
 213                       0
 214                       code-length))
 215       code)))
 216
 217 ;;; Moving native code during a GC or purify is not so trivial on the
 218 ;;; x86 port.
 219 ;;;
 220 ;;; Our strategy for allowing the loading of x86 native code into the
 221 ;;; dynamic heap requires that the addresses of fixups be saved for
 222 ;;; all these code objects. After a purify these fixups can be
 223 ;;; dropped. In CMU CL, this policy was enabled with
 224 ;;; *ENABLE-DYNAMIC-SPACE-CODE*; in SBCL it's always used.
 225 #!+x86
 226 (defun load-code (box-num code-length)
 227   (declare (fixnum box-num code-length))
 228   (with-fop-stack t
 229     (let ((stuff (list (pop-stack))))
 230       (dotimes (i box-num)
 231         (declare (fixnum i))
 232         (push (pop-stack) stuff))
 233       (let* ((dbi (car (last stuff)))   ; debug-info
 234              (tto (first stuff)))       ; trace-table-offset
 235
 236         (setq stuff (nreverse stuff))
 237
 238         ;; FIXME: *LOAD-CODE-VERBOSE* should probably be #!+SB-SHOW.
 239         (when *load-code-verbose*
 240               (format t "stuff: ~S~%" stuff)
 241               (format t
 242                       "   : ~S ~S ~S ~S~%"
 243                       (sb!c::compiled-debug-info-p dbi)
 244                       (sb!c::debug-info-p dbi)
 245                       (sb!c::compiled-debug-info-name dbi)
 246                       tto)
 247               (format t "   loading to the dynamic space~%"))
 248
 249         (let ((code (%primitive sb!c:allocate-code-object
 250                                 box-num
 251                                 code-length))
 252               (index (+ sb!vm:code-trace-table-offset-slot box-num)))
 253           (declare (type index index))
 254           (when *load-code-verbose*
 255             (format t
 256                     "  obj addr=~X~%"
 257                     (sb!kernel::get-lisp-obj-address code)))
 258           (setf (%code-debug-info code) (pop stuff))
 259           (dotimes (i box-num)
 260             (declare (fixnum i))
 261             (setf (code-header-ref code (decf index)) (pop stuff)))
 262           (sb!sys:without-gcing
 263            (read-n-bytes *fasl-input-stream*
 264                          (code-instructions code)
 265                          0
 266                          code-length))
 267           code)))))
 268 \f
 269 ;;;; linkage fixups
 270
 271 ;;; how we learn about assembler routines at startup
 272 (defvar *!initial-assembler-routines*)
 273
 274 (defun !loader-cold-init ()
 275   (/show0 "/!loader-cold-init")
 276   (dolist (routine *!initial-assembler-routines*)
 277     (setf (gethash (car routine) *assembler-routines*) (cdr routine))))