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' id ( `,' id )* `;'
  35   (declare (ignore pset))
  36   (with-parser-context (token-scanner-context :scanner scanner)
  37     (parse (and "typename"
  38                 (skip-many (:min 1)
  39                   (seq ((id :id))
  40                     (if (gethash id *module-type-map*)
  41                         (cerror* "Type `~A' already defined" id)
  42                         (add-to-module *module*
  43                                        (make-instance 'type-item
  44                                                       :name id))))
  45                   #\,)
  46                 #\;))))
  47
  48 ;;; Fragments.
  49
  50 (define-pluggable-parser module code (scanner pset)
  51   ;; `code' id `:' item-name [constraints] `{' c-fragment `}'
  52   ;;
  53   ;; constrains ::= `[' constraint-list `]'
  54   ;; constraint ::= item-name+
  55   ;; item-name ::= id | `(' id+ `)'
  56   (declare (ignore pset))
  57   (with-parser-context (token-scanner-context :scanner scanner)
  58     (labels ((kw ()
  59                (parse (seq ((kw :id))
  60                         (intern (frob-identifier kw) 'keyword))))
  61              (item ()
  62                (parse (or (kw)
  63                           (seq (#\( (names (list (:min 1) (kw))) #\))
  64                             names)))))
  65       (parse (seq ("code"
  66                    (reason (kw))
  67                    #\:
  68                    (name (item))
  69                    (constraints (? (seq (#\[
  70                                          (constraints (list (:min 1)
  71                                                         (list (:min 1)
  72                                                           (item))
  73                                                         #\,))
  74                                          #\])
  75                                      constraints)))
  76                    (fragment (parse-delimited-fragment scanner #\{ #\})))
  77                (add-to-module *module*
  78                               (make-instance 'code-fragment-item
  79                                              :fragment fragment
  80                                              :constraints constraints
  81                                              :reason reason
  82                                              :name name)))))))
  83
  84 ;;; External files.
  85
  86 (export 'read-module)
  87 (defun read-module (pathname &key (truename nil truep) location)
  88   "Parse the file at PATHNAME as a module, returning it.
  89
  90    This is the main entry point for parsing module files.  You may well know
  91    the file's TRUENAME already (e.g., because `probe-file' dropped it into
  92    your lap) so you can avoid repeating the search by providing it.
  93
  94    The LOCATION is the thing which wanted the module imported -- usually a
  95    `file-location' object, though it might be anything other than `t' which
  96    can be printed in the event of circular imports."
  97
  98   (setf pathname (merge-pathnames pathname
  99                                   (make-pathname :type "SOD" :case :common)))
 100   (unless truep (setf truename (truename pathname)))
 101   (define-module (pathname :location location :truename truename)
 102     (with-open-file (f-stream pathname :direction :input)
 103       (let* ((*readtable* (copy-readtable))
 104              (*package* (find-package '#:sod-user))
 105              (char-scanner (make-instance 'charbuf-scanner
 106                                           :stream f-stream))
 107              (scanner (make-instance 'sod-token-scanner
 108                                      :char-scanner char-scanner)))
 109         (with-default-error-location (scanner)
 110           (with-parser-context (token-scanner-context :scanner scanner)
 111             (parse (skip-many ()
 112                      (seq ((pset (parse-property-set scanner))
 113                            (nil (error ()
 114                                   (plug module scanner pset))))
 115                        (check-unused-properties pset))))))))))
 116
 117 (define-pluggable-parser module test (scanner pset)
 118   ;; `demo' string `;'
 119   (declare (ignore pset))
 120   (with-parser-context (token-scanner-context :scanner scanner)
 121     (parse (seq ("demo" (string :string) #\;)
 122              (format t ";; DEMO ~S~%" string)))))
 123
 124 (define-pluggable-parser module file (scanner pset)
 125   ;; `import' string `;'
 126   ;; `load' string `;'
 127   (declare (ignore pset))
 128   (flet ((common (name type what thunk)
 129            (find-file scanner
 130                       (merge-pathnames name
 131                                        (make-pathname :type type
 132                                                       :case :common))
 133                       what
 134                       thunk)))
 135     (with-parser-context (token-scanner-context :scanner scanner)
 136       (parse (or (seq ("import" (name :string) #\;)
 137                    (common name "SOD" "module"
 138                            (lambda (path true)
 139                              (handler-case
 140                                  (let ((module (read-module path
 141                                                             :truename true)))
 142                                    (when module
 143                                      (module-import module)
 144                                      (pushnew module
 145                                               (module-dependencies
 146                                                *module*))))
 147                                (file-error (error)
 148                                  (cerror* "Error reading module ~S: ~A"
 149                                           path error))))))
 150                  (seq ("load" (name :string) #\;)
 151                    (common name "LISP" "Lisp file"
 152                            (lambda (path true)
 153                              (handler-case
 154                                  (load true :verbose nil :print nil)
 155                                (error (error)
 156                                  (cerror* "Error loading Lisp file ~S: ~A"
 157                                           path error)))))))))))
 158
 159 ;;; Setting properties.
 160
 161 (define-pluggable-parser module set (scanner pset)
 162   ;; `set' property-list `;'
 163   (with-parser-context (token-scanner-context :scanner scanner)
 164     (parse (and "set"
 165                 (lisp (let ((module-pset (module-pset *module*)))
 166                         (when pset
 167                           (pset-map (lambda (prop)
 168                                       (add-property module-pset
 169                                                     (p-name prop)
 170                                                     (p-value prop)
 171                                                     :type (p-type prop)
 172                                                     :location (p-location prop))
 173                                       (setf (p-seenp prop) t))
 174                                     pset))
 175                         (parse (skip-many (:min 0)
 176                                  (error (:ignore-unconsumed t)
 177                                    (parse-property scanner module-pset)
 178                                    (skip-until (:keep-end t) #\, #\;))
 179                                  #\,))))
 180                 #\;))))
 181
 182 ;;; Lisp escape.
 183
 184 (define-pluggable-parser module lisp (scanner pset)
 185   ;; `lisp' s-expression `;'
 186   (declare (ignore pset))
 187   (with-parser-context (token-scanner-context :scanner scanner)
 188     (parse (seq ((sexp (if (and (eql (token-type scanner) :id)
 189                                 (string= (token-value scanner) "lisp"))
 190                            (let* ((stream (make-scanner-stream scanner))
 191                                   (sexp (read stream t)))
 192                              (scanner-step scanner)
 193                              (values sexp t t))
 194                            (values '((:id "lisp")) nil nil)))
 195                  #\;)
 196              (eval sexp)))))
 197
 198 ;;;--------------------------------------------------------------------------
 199 ;;; Class declarations.
 200
 201 (export 'class-item)
 202
 203 (define-pluggable-parser class-item initfrags (scanner class pset)
 204   ;; raw-class-item ::= frag-keyword `{' c-fragment `}'
 205   ;; frag-keyword ::= `init' | `teardown'
 206   (with-parser-context (token-scanner-context :scanner scanner)
 207     (parse (seq ((make (or (seq ("init") #'make-sod-class-initfrag)
 208                            (seq ("teardown") #'make-sod-class-tearfrag)))
 209                  (frag (parse-delimited-fragment scanner #\{ #\})))
 210              (funcall make class frag pset scanner)))))
 211
 212 (define-pluggable-parser class-item initargs (scanner class pset)
 213   ;; initarg-item ::= `initarg' declspec+ init-declarator-list
 214   ;; init-declarator ::= declarator [`=' initializer]
 215   (with-parser-context (token-scanner-context :scanner scanner)
 216     (parse (seq ("initarg"
 217                  (base-type (parse-c-type scanner))
 218                  (nil (skip-many (:min 1)
 219                         (seq ((declarator (parse-declarator scanner
 220                                                             base-type))
 221                               (init (? (parse-delimited-fragment
 222                                         scanner #\= (list #\; #\,)
 223                                         :keep-end t))))
 224                           (make-sod-user-initarg class
 225                                                  (cdr declarator)
 226                                                  (car declarator)
 227                                                  pset init scanner))
 228                         #\,))
 229                    #\;)))))
 230
 231 (defun parse-class-body (scanner pset name supers)
 232   ;; class-body ::= `{' class-item* `}'
 233   ;;
 234   ;; class-item ::= property-set raw-class-item
 235   (with-parser-context (token-scanner-context :scanner scanner)
 236     (make-class-type name)
 237     (let* ((class (make-sod-class name (mapcar #'find-sod-class supers)
 238                                   pset scanner))
 239            (nick (sod-class-nickname class)))
 240
 241       (labels ((parse-maybe-dotted-declarator (base-type)
 242                  ;; Parse a declarator or dotted-declarator, i.e., one whose
 243                  ;; centre is
 244                  ;;
 245                  ;; maybe-dotted-identifier ::= [id `.'] id
 246                  ;;
 247                  ;; A plain identifier is returned as a string, as usual; a
 248                  ;; dotted identifier is returned as a cons cell of the two
 249                  ;; names.
 250                  (parse-declarator
 251                   scanner base-type
 252                   :keywordp t
 253                   :kernel (parser ()
 254                             (seq ((name-a :id)
 255                                   (name-b (? (seq (#\. (id :id)) id))))
 256                               (if name-b (cons name-a name-b)
 257                                   name-a)))))
 258
 259                (parse-message-item (sub-pset type name)
 260                  ;; message-item ::=
 261                  ;;     declspec+ declarator -!- (method-body | `;')
 262                  ;;
 263                  ;; Don't allow a method-body here if the message takes a
 264                  ;; varargs list, because we don't have a name for the
 265                  ;; `va_list' parameter.
 266                  (let ((message (make-sod-message class name type
 267                                                   sub-pset scanner)))
 268                    (if (varargs-message-p message)
 269                        (parse #\;)
 270                        (parse (or #\; (parse-method-item sub-pset
 271                                                          type nick name))))))
 272
 273                (parse-method-item (sub-pset type sub-nick name)
 274                  ;; method-item ::=
 275                  ;;     declspec+ dotted-declarator -!- method-body
 276                  ;;
 277                  ;; method-body ::= `{' c-fragment `}' | `extern' `;'
 278                  (parse (seq ((body (or (seq ("extern" #\;) nil)
 279                                         (parse-delimited-fragment
 280                                          scanner #\{ #\}))))
 281                           (make-sod-method class sub-nick name type
 282                                            body sub-pset scanner))))
 283
 284                (parse-initializer ()
 285                  ;; initializer ::= `=' c-fragment
 286                  ;;
 287                  ;; Return a VALUE, ready for passing to a `sod-initializer'
 288                  ;; constructor.
 289                  (parse-delimited-fragment scanner #\= (list #\, #\;)
 290                                            :keep-end t))
 291
 292                (parse-slot-item (sub-pset base-type type name)
 293                  ;; slot-item ::=
 294                  ;;     declspec+ declarator -!- [initializer]
 295                  ;;             [`,' init-declarator-list] `;'
 296                  ;;
 297                  ;; init-declarator-list ::=
 298                  ;;     declarator [initializer] [`,' init-declarator-list]
 299                  (parse (and (seq ((init (? (parse-initializer))))
 300                                (make-sod-slot class name type
 301                                               sub-pset scanner)
 302                                (when init
 303                                  (make-sod-instance-initializer
 304                                   class nick name init sub-pset scanner)))
 305                              (skip-many ()
 306                                (seq (#\,
 307                                      (ds (parse-declarator scanner
 308                                                            base-type))
 309                                      (init (? (parse-initializer))))
 310                                  (make-sod-slot class (cdr ds) (car ds)
 311                                                 sub-pset scanner)
 312                                  (when init
 313                                    (make-sod-instance-initializer
 314                                     class nick (cdr ds) init
 315                                     sub-pset scanner))))
 316                              #\;)))
 317
 318                (parse-initializer-item (sub-pset must-init-p constructor)
 319                  ;; initializer-item ::=
 320                  ;;     [`class'] -!- slot-initializer-list `;'
 321                  ;;
 322                  ;; slot-initializer ::= id `.' id [initializer]
 323                  (let ((parse-init (if must-init-p
 324                                        #'parse-initializer
 325                                        (parser () (? (parse-initializer))))))
 326                    (parse (and (skip-many ()
 327                                  (seq ((name-a :id) #\. (name-b :id)
 328                                        (init (funcall parse-init)))
 329                                    (funcall constructor class
 330                                             name-a name-b init
 331                                             sub-pset scanner))
 332                                  #\,)
 333                                #\;))))
 334
 335                (class-item-dispatch (sub-pset base-type type name)
 336                  ;; Logically part of `parse-raw-class-item', but the
 337                  ;; indentation was getting crazy.  We're currently at
 338                  ;;
 339                  ;; raw-class-item ::=
 340                  ;;     declspec+ (declarator | dotted-declarator) -!- ...
 341                  ;;   | other-items
 342                  ;;
 343                  ;; If the declarator is dotted then this must be a method
 344                  ;; definition; otherwise it might be a message or slot.
 345                  (cond ((not (typep type 'c-function-type))
 346                         (when (consp name)
 347                           (cerror*-with-location
 348                            scanner
 349                            "Method declarations must have function type.")
 350                           (setf name (cdr name)))
 351                         (parse-slot-item sub-pset base-type type name))
 352                        ((consp name)
 353                         (parse-method-item sub-pset type
 354                                            (car name) (cdr name)))
 355                        (t
 356                         (parse-message-item sub-pset type name))))
 357
 358                (parse-raw-class-item (sub-pset)
 359                  ;; raw-class-item ::=
 360                  ;;     message-item
 361                  ;;   | method-item
 362                  ;;   | slot-item
 363                  ;;   | initializer-item
 364                  ;;   | initfrag-item
 365                  ;;
 366                  ;; Most of the above begin with declspecs and a declarator
 367                  ;; (which might be dotted).  So we parse that here and
 368                  ;; dispatch based on what we find.
 369                  (parse (or (plug class-item scanner class sub-pset)
 370                             (peek
 371                              (seq ((ds (parse-c-type scanner))
 372                                    (dc (parse-maybe-dotted-declarator ds))
 373                                    (nil (commit))
 374                                    (nil (class-item-dispatch sub-pset
 375                                                              ds
 376                                                              (car dc)
 377                                                              (cdr dc))))))
 378                             (and "class"
 379                                  (parse-initializer-item
 380                                   sub-pset t
 381                                   #'make-sod-class-initializer))
 382                             (parse-initializer-item
 383                              sub-pset nil
 384                              #'make-sod-instance-initializer)))))
 385
 386         (parse (seq (#\{
 387                      (nil (skip-many ()
 388                             (seq ((sub-pset (parse-property-set scanner))
 389                                   (nil (parse-raw-class-item sub-pset)))
 390                               (check-unused-properties sub-pset))))
 391                      (nil (error () #\})))
 392                  (finalize-sod-class class)
 393                  (add-to-module *module* class)))))))
 394
 395 (define-pluggable-parser module class (scanner pset)
 396   ;; `class' id [`:' id-list] class-body
 397   ;; `class' id `;'
 398   (with-parser-context (token-scanner-context :scanner scanner)
 399     (parse (seq ("class"
 400                  (name :id)
 401                  (nil (or (seq (#\;)
 402                             (make-class-type name))
 403                           (seq ((supers (? (seq (#\: (ids (list () :id #\,)))
 404                                              ids)))
 405                                 (nil (parse-class-body
 406                                       scanner
 407                                       pset name supers)))))))))))
 408
 409 ;;;----- That's all, folks --------------------------------------------------