chiark - git - mdw - sod/blob - src/module-parse.lisp

   1 ;;; -*-lisp-*-
   2 ;;;
   3 ;;; Top-level parser for module syntax
   4 ;;;
   5 ;;; (c) 2010 Straylight/Edgeware
   6 ;;;
   7
   8 ;;;----- Licensing notice ---------------------------------------------------
   9 ;;;
  10 ;;; This file is part of the Sensible Object Design, an object system for C.
  11 ;;;
  12 ;;; SOD is free software; you can redistribute it and/or modify
  13 ;;; it under the terms of the GNU General Public License as published by
  14 ;;; the Free Software Foundation; either version 2 of the License, or
  15 ;;; (at your option) any later version.
  16 ;;;
  17 ;;; SOD is distributed in the hope that it will be useful,
  18 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;;; GNU General Public License for more details.
  21 ;;;
  22 ;;; You should have received a copy of the GNU General Public License
  23 ;;; along with SOD; if not, write to the Free Software Foundation,
  24 ;;; Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25
  26 (in-package #:sod)
  27
  28 ;;;--------------------------------------------------------------------------
  29 ;;; Toplevel syntax.
  30
  31 ;;; Type names.
  32
  33 (define-pluggable-parser module typename (scanner pset)
  34   ;; `typename' list[id] `;'
  35   (declare (ignore pset))
  36   (with-parser-context (token-scanner-context :scanner scanner)
  37     (parse (and "typename"
  38                 (skip-many ()
  39                   (error ()
  40                       (seq ((id :id))
  41                         (if (or (gethash id *module-type-map*)
  42                                 (find-simple-c-type id))
  43                             (cerror* "Type `~A' already defined" id)
  44                             (add-to-module *module*
  45                                            (make-instance 'type-item
  46                                                           :name id))))
  47                     (skip-until () #\, #\;))
  48                   #\,)
  49                 (must #\;)))))
  50
  51 ;;; Fragments.
  52
  53 (define-pluggable-parser module code (scanner pset)
  54   ;; `code' id `:' item-name [constraints] `{' c-fragment `}'
  55   ;;
  56   ;; constraints ::= `[' list[constraint] `]'
  57   ;; constraint ::= item-name+
  58   ;; item-name ::= id | `(' id+ `)'
  59   (declare (ignore pset))
  60   (with-parser-context (token-scanner-context :scanner scanner)
  61     (labels ((kw ()
  62                (parse (seq ((kw :id))
  63                         (intern (frob-identifier kw) 'keyword))))
  64              (item ()
  65                (parse (or (kw)
  66                           (seq (#\( (names (list (:min 1) (kw))) #\))
  67                             names))))
  68              (constraints ()
  69                (parse (seq (#\[
  70                             (constraints
  71                              (list ()
  72                                (list (:min 1)
  73                                  (error (:ignore-unconsumed t) (item)
  74                                    (skip-until () :id #\( #\, #\])))
  75                                #\,))
  76                             #\])
  77                         constraints)))
  78              (fragment ()
  79                (parse-delimited-fragment scanner #\{ #\})))
  80       (parse (seq ("code"
  81                    (reason (must (kw)))
  82                    (nil (must #\:))
  83                    (item (or (seq ((name (must (item)))
  84                                    (constraints (? (constraints)))
  85                                    (fragment (fragment)))
  86                                (and name
  87                                     (make-instance 'code-fragment-item
  88                                                    :reason reason
  89                                                    :constraints constraints
  90                                                    :name name
  91                                                    :fragment fragment))))))
  92                (when item (add-to-module *module* item)))))))
  93
  94 ;;; External files.
  95
  96 (export 'read-module)
  97 (defun read-module (pathname &key (truename nil truep) location)
  98   "Parse the file at PATHNAME as a module, returning it.
  99
 100    This is the main entry point for parsing module files.  You may well know
 101    the file's TRUENAME already (e.g., because `probe-file' dropped it into
 102    your lap) so you can avoid repeating the search by providing it.
 103
 104    The LOCATION is the thing which wanted the module imported -- usually a
 105    `file-location' object, though it might be anything other than `t' which
 106    can be printed in the event of circular imports."
 107
 108   (setf pathname (merge-pathnames pathname
 109                                   (make-pathname :type "SOD" :case :common)))
 110   (unless truep (setf truename (truename pathname)))
 111   (define-module (pathname :location location :truename truename)
 112     (with-open-file (f-stream pathname :direction :input)
 113       (let* ((char-scanner (make-instance 'charbuf-scanner
 114                                           :stream f-stream
 115                                           :filename (namestring pathname)))
 116              (scanner (make-instance 'sod-token-scanner
 117                                      :char-scanner char-scanner)))
 118         (with-default-error-location (scanner)
 119           (with-parser-context (token-scanner-context :scanner scanner)
 120             (multiple-value-bind (result winp consumedp)
 121                 (parse (skip-many ()
 122                           (seq ((pset (parse-property-set scanner))
 123                                 (nil (error ()
 124                                          (plug module scanner pset)
 125                                        (skip-until (:keep-end nil)
 126                                          #\; #\}))))
 127                             (check-unused-properties pset))))
 128               (declare (ignore consumedp))
 129               (unless winp (syntax-error scanner result)))))))))
 130
 131 (define-pluggable-parser module file (scanner pset)
 132   ;; `import' string `;'
 133   ;; `load' string `;'
 134   (declare (ignore pset))
 135   (flet ((common (name type what thunk)
 136            (when name
 137              (find-file (pathname (scanner-filename scanner))
 138                         (merge-pathnames name
 139                                          (make-pathname :type type
 140                                                         :case :common))
 141                         what
 142                         thunk))))
 143     (with-parser-context (token-scanner-context :scanner scanner)
 144       (parse (or (seq ("import" (name (must :string)) (nil (must #\;)))
 145                    (common name "SOD" "module"
 146                            (lambda (path true)
 147                              (handler-case
 148                                  (let ((module (read-module path
 149                                                             :truename true)))
 150                                    (when module
 151                                      (module-import module)
 152                                      (pushnew path (module-files *module*))
 153                                      (pushnew module
 154                                               (module-dependencies
 155                                                *module*))))
 156                                (file-error (error)
 157                                  (cerror* "Error reading module ~S: ~A"
 158                                           path error))
 159                                (error (error)
 160                                  (cerror* "Unexpected error reading ~
 161                                            module ~S: ~A"
 162                                           path error))))))
 163                  (seq ("load" (name (must :string)) (nil (must #\;)))
 164                    (common name "LISP" "Lisp file"
 165                            (lambda (path true)
 166                              (handler-case
 167                                  (progn
 168                                    (pushnew path (module-files *module*))
 169                                    (load true :verbose nil :print nil))
 170                                (error (error)
 171                                  (cerror* "Error loading Lisp file ~S: ~A"
 172                                           path error)))))))))))
 173
 174 ;;; Setting properties.
 175
 176 (define-pluggable-parser module set (scanner pset)
 177   ;; `set' list[property] `;'
 178   (with-parser-context (token-scanner-context :scanner scanner)
 179     (parse (and "set"
 180                 (lisp (let ((module-pset (module-pset *module*)))
 181                         (when pset
 182                           (pset-map (lambda (prop)
 183                                       (add-property
 184                                        module-pset
 185                                        (p-name prop) (p-value prop)
 186                                        :type (p-type prop)
 187                                        :location (p-location prop))
 188                                       (setf (p-seenp prop) t))
 189                                     pset))
 190                         (parse (skip-many (:min (if pset 0 1))
 191                                  (error (:ignore-unconsumed t)
 192                                      (parse-property scanner module-pset)
 193                                    (skip-until () #\, #\;))
 194                                  #\,))))
 195                 #\;))))
 196
 197 ;;; Lisp escape.
 198
 199 (define-pluggable-parser module lisp (scanner pset)
 200   ;; `lisp' s-expression `;'
 201   (declare (ignore pset))
 202   (with-parser-context (token-scanner-context :scanner scanner)
 203     (parse (seq ((sexp (if (and (eql (token-type scanner) :id)
 204                                 (string= (token-value scanner) "lisp"))
 205                            (let* ((stream (make-scanner-stream scanner))
 206                                   (sexp (read stream t)))
 207                              (scanner-step scanner)
 208                              (values sexp t t))
 209                            (values '((:id "lisp")) nil nil)))
 210                  (nil (must #\;)))
 211              (eval sexp)))))
 212
 213 ;;;--------------------------------------------------------------------------
 214 ;;; Class declarations.
 215
 216 (export 'class-item)
 217
 218 (define-pluggable-parser class-item initfrags (scanner class pset)
 219   ;; raw-class-item ::= frag-keyword `{' c-fragment `}'
 220   ;; frag-keyword ::= `init' | `teardown'
 221   (with-parser-context (token-scanner-context :scanner scanner)
 222     (parse (seq ((make (or (seq ("init") #'make-sod-class-initfrag)
 223                            (seq ("teardown") #'make-sod-class-tearfrag)))
 224                  (frag (parse-delimited-fragment scanner #\{ #\})))
 225              (funcall make class frag pset :location scanner)))))
 226
 227 (define-pluggable-parser class-item initargs (scanner class pset)
 228   ;; initarg-item ::= `initarg' declspec+ list[init-declarator]
 229   ;; init-declarator ::= declarator [`=' initializer]
 230   (with-parser-context (token-scanner-context :scanner scanner)
 231     (parse (seq ("initarg"
 232                  (base-type (parse-c-type scanner))
 233                  (nil (skip-many (:min 1)
 234                         (seq ((declarator (parse-declarator scanner
 235                                                             base-type))
 236                               (init (? (parse-delimited-fragment
 237                                         scanner #\= (list #\; #\,)
 238                                         :keep-end t))))
 239                           (make-sod-user-initarg class
 240                                                  (cdr declarator)
 241                                                  (car declarator)
 242                                                  pset
 243                                                  :default init
 244                                                  :location scanner))
 245                         #\,))
 246                  (nil (must #\;)))))))
 247
 248 (defun synthetic-name ()
 249   "Return an obviously bogus synthetic not-identifier."
 250   (let ((ix *temporary-index*))
 251     (incf *temporary-index*)
 252     (make-instance 'temporary-variable :tag (format nil "%%#~A" ix))))
 253
 254 (defun parse-class-body (scanner pset name supers)
 255   ;; class-body ::= `{' class-item* `}'
 256   ;;
 257   ;; class-item ::= property-set raw-class-item
 258   (with-parser-context (token-scanner-context :scanner scanner)
 259     (when name (make-class-type name))
 260     (let* ((duff (null name))
 261            (superclasses
 262             (let ((superclasses (restart-case
 263                                     (mapcar #'find-sod-class
 264                                             (or supers (list "SodObject")))
 265                                   (continue ()
 266                                     (setf duff t)
 267                                     (list (find-sod-class "SodObject"))))))
 268               (find-duplicates (lambda (first second)
 269                                  (declare (ignore second))
 270                                  (setf duff t)
 271                                  (cerror* "Class `~A' has duplicate ~
 272                                            direct superclass `~A'"
 273                                           name first))
 274                                superclasses)
 275               (delete-duplicates superclasses)))
 276            (synthetic-name (or name
 277                                (let ((var (synthetic-name)))
 278                                  (unless pset
 279                                    (setf pset (make-property-set)))
 280                                  (unless (pset-get pset "nick")
 281                                    (add-property pset "nick" var :type :id))
 282                                  var)))
 283            (class (make-sod-class synthetic-name superclasses pset
 284                                   :location scanner))
 285            (nick (sod-class-nickname class)))
 286
 287       (labels ((must-id ()
 288                  (parse (must :id (progn (setf duff t) (synthetic-name)))))
 289
 290                (parse-maybe-dotted-name ()
 291                  ;; maybe-dotted-name ::= [id `.'] id
 292                  ;;
 293                  ;; A plain identifier is returned as a string, as usual; a
 294                  ;; dotted identifier is returned as a cons cell of the two
 295                  ;; names.
 296                  (parse (seq ((name-a (must-id))
 297                               (name-b (? (seq (#\. (id (must-id))) id))))
 298                           (if name-b (cons name-a name-b)
 299                               name-a))))
 300
 301                (parse-maybe-dotted-declarator (base-type)
 302                  ;; Parse a declarator or dotted-declarator, i.e., one whose
 303                  ;; centre is maybe-dotted-name above.
 304                  (parse-declarator scanner base-type
 305                                    :keywordp t
 306                                    :kernel #'parse-maybe-dotted-name))
 307
 308                (parse-message-item (sub-pset type name)
 309                  ;; message-item ::=
 310                  ;;     declspec+ declarator -!- (method-body | `;')
 311                  ;;
 312                  ;; Don't allow a method-body here if the message takes a
 313                  ;; varargs list, because we don't have a name for the
 314                  ;; `va_list' parameter.
 315                  (let ((message (make-sod-message class name type sub-pset
 316                                                   :location scanner)))
 317                    (if (varargs-message-p message)
 318                        (parse #\;)
 319                        (parse (or #\; (parse-method-item sub-pset
 320                                                          type nick name))))))
 321
 322                (parse-method-item (sub-pset type sub-nick name)
 323                  ;; method-item ::=
 324                  ;;     declspec+ dotted-declarator -!- method-body
 325                  ;;
 326                  ;; method-body ::= `{' c-fragment `}' | `extern' `;'
 327                  (parse (seq ((body (or (seq ("extern" #\;) nil)
 328                                         (parse-delimited-fragment
 329                                          scanner #\{ #\}))))
 330                           (restart-case
 331                               (make-sod-method class sub-nick name type
 332                                                body sub-pset
 333                                                :location scanner)
 334                             (continue () :report "Continue")))))
 335
 336                (parse-initializer ()
 337                  ;; initializer ::= `=' c-fragment
 338                  ;;
 339                  ;; Return a VALUE, ready for passing to a `sod-initializer'
 340                  ;; constructor.
 341                  (parse-delimited-fragment scanner #\= '(#\, #\;)
 342                                            :keep-end t))
 343
 344                (parse-slot-item (sub-pset base-type type name)
 345                  ;; slot-item ::=
 346                  ;;     declspec+ declarator -!- [initializer]
 347                  ;;             [`,' list[init-declarator]] `;'
 348                  ;;
 349                  ;; init-declarator ::= declarator [initializer]
 350                  (flet ((make-it (name type init)
 351                           (restart-case
 352                               (progn
 353                                 (make-sod-slot class name type sub-pset
 354                                                :location scanner)
 355                                 (when init
 356                                   (make-sod-instance-initializer
 357                                    class nick name init sub-pset
 358                                    :location scanner)))
 359                             (continue () :report "Continue"))))
 360                    (parse (and (error ()
 361                                    (seq ((init (? (parse-initializer))))
 362                                      (make-it name type init))
 363                                  (skip-until () #\, #\;))
 364                                (skip-many ()
 365                                  (error (:ignore-unconsumed t)
 366                                      (seq (#\,
 367                                            (ds (parse-declarator scanner
 368                                                                  base-type))
 369                                            (init (? (parse-initializer))))
 370                                        (make-it (cdr ds) (car ds) init))
 371                                    (skip-until () #\, #\;)))
 372                                (must #\;)))))
 373
 374                (parse-initializer-item (sub-pset must-init-p constructor)
 375                  ;; initializer-item ::=
 376                  ;;     [`class'] -!- list[slot-initializer] `;'
 377                  ;;
 378                  ;; slot-initializer ::= id `.' id [initializer]
 379                  (let ((parse-init (if must-init-p #'parse-initializer
 380                                        (parser () (? (parse-initializer))))))
 381                    (parse (and (skip-many ()
 382                                  (error (:ignore-unconsumed t)
 383                                      (seq ((name-a :id) #\.
 384                                            (name-b (must-id))
 385                                            (init (funcall parse-init)))
 386                                        (restart-case
 387                                            (funcall constructor class
 388                                                     name-a name-b init
 389                                                     sub-pset
 390                                                     :location scanner)
 391                                          (continue () :report "Continue")))
 392                                    (skip-until () #\, #\;))
 393                                  #\,)
 394                                (must #\;)))))
 395
 396                (class-item-dispatch (sub-pset base-type type name)
 397                  ;; Logically part of `parse-raw-class-item', but the
 398                  ;; indentation was getting crazy.  We're currently at
 399                  ;;
 400                  ;; raw-class-item ::=
 401                  ;;     declspec+ (declarator | dotted-declarator) -!- ...
 402                  ;;   | other-items
 403                  ;;
 404                  ;; If the declarator is dotted then this must be a method
 405                  ;; definition; otherwise it might be a message or slot.
 406                  (cond ((not (typep type 'c-function-type))
 407                         (when (consp name)
 408                           (cerror*
 409                            "Method declarations must have function type")
 410                           (setf name (cdr name)))
 411                         (parse-slot-item sub-pset base-type type name))
 412                        ((consp name)
 413                         (parse-method-item sub-pset type
 414                                            (car name) (cdr name)))
 415                        (t
 416                         (parse-message-item sub-pset type name))))
 417
 418                (parse-raw-class-item (sub-pset)
 419                  ;; raw-class-item ::=
 420                  ;;     message-item
 421                  ;;   | method-item
 422                  ;;   | slot-item
 423                  ;;   | initializer-item
 424                  ;;   | initfrag-item
 425                  ;;
 426                  ;; Most of the above begin with declspecs and a declarator
 427                  ;; (which might be dotted).  So we parse that here and
 428                  ;; dispatch based on what we find.
 429                  (parse (or (plug class-item scanner class sub-pset)
 430                             (peek
 431                              (seq ((ds (parse-c-type scanner))
 432                                    (dc (parse-maybe-dotted-declarator ds))
 433                                    (nil (commit))
 434                                    (nil (class-item-dispatch sub-pset
 435                                                              ds
 436                                                              (car dc)
 437                                                              (cdr dc))))))
 438                             (and "class"
 439                                  (parse-initializer-item sub-pset t
 440                                   #'make-sod-class-initializer))
 441                             (parse-initializer-item sub-pset nil
 442                              #'make-sod-instance-initializer)))))
 443
 444         (parse (seq ((nil (must #\{))
 445                      (nil (skip-many ()
 446                             (seq ((sub-pset (parse-property-set scanner))
 447                                   (nil (parse-raw-class-item sub-pset)))
 448                               (check-unused-properties sub-pset))))
 449                      (nil (must #\})))
 450                  (unless (finalize-sod-class class)
 451                    (setf duff t))
 452                  (unless duff
 453                    (add-to-module *module* class))))))))
 454
 455 (define-pluggable-parser module class (scanner pset)
 456   ;; `class' id `:' list[id] class-body
 457   ;; `class' id `;'
 458   (with-parser-context (token-scanner-context :scanner scanner)
 459     (parse (seq ("class"
 460                  (name (must :id))
 461                  (nil (or (seq (#\;)
 462                             (when name (make-class-type name)))
 463                           (seq ((supers (must (seq (#\:
 464                                                     (ids (list () :id #\,)))
 465                                                 ids)))
 466                                 (nil (parse-class-body
 467                                       scanner
 468                                       pset name supers)))))))))))
 469
 470 ;;;----- That's all, folks --------------------------------------------------