src/code/external-formats/mb-util.lisp

   1 (in-package "SB!IMPL")
   2
   3 (defun make-multibyte-mapper (list)
   4   (let ((list (sort (copy-list list) #'< :key #'car))
   5         (hi (loop for x in list maximize (max (car x) (cadr x)))))
   6     (make-array (list (length list) 2)
   7                 :element-type (list 'integer 0 hi)
   8                 :initial-contents list)))
   9
  10 (defmacro define-multibyte-mapper (name list)
  11   `(defparameter ,name
  12      (make-multibyte-mapper ,list)))
  13
  14 (defun get-multibyte-mapper (table code)
  15   (declare (optimize speed (safety 0))
  16            (type (array * (* 2)) table)
  17            (type fixnum code))
  18   (labels ((recur (start end)
  19              (declare (type fixnum start end))
  20              (let* ((m (ash (+ start end) -1))
  21                     (x (aref table m 0)))
  22                (declare (type fixnum m x))
  23                (cond ((= x code)
  24                       (aref table m 1))
  25                      ((and (< x code) (< m end))
  26                       (recur (1+ m) end))
  27                      ((and (> x code) (> m start))
  28                       (recur start (1- m)))))))
  29     (recur 0 (1- (array-dimension table 0)))))
  30
  31 (eval-when (:compile-toplevel :load-toplevel :execute)
  32   ;; FIXME: better to change make-od-name() to accept multiple
  33   ;; arguments in octets.lisp?
  34   (defun make-od-name-list (&rest syms)
  35     (reduce #'make-od-name syms))
  36
  37   (defun define-bytes-per-mb-character-1 (accessor type format
  38                                           mb-len mb-continuation-byte-p)
  39     (let ((name (make-od-name-list 'bytes-per format 'character accessor))
  40           (invalid-mb-starter-byte
  41            (make-od-name-list 'invalid format 'starter-byte))
  42           (invalid-mb-continuation-byte
  43            (make-od-name-list 'invalid format 'continuation-byte)))
  44       `(progn
  45          ;;(declaim (inline ,name))
  46          (defun ,name (array pos end)
  47            (declare (optimize speed (safety 0))
  48                     (type ,type array)
  49                     (type array-range pos end))
  50            ;; returns the number of bytes consumed and nil if it's a
  51            ;; valid character or the number of bytes consumed and a
  52            ;; replacement string if it's not.
  53            (let ((initial-byte (,accessor array pos))
  54                  (reject-reason nil)
  55                  (reject-position pos)
  56                  (remaining-bytes (- end pos)))
  57              (declare (type array-range reject-position remaining-bytes))
  58              (labels ((valid-starter-byte-p (b)
  59                         (declare (type (unsigned-byte 8) b))
  60                         (let ((ok (,mb-len b)))
  61                           (unless ok
  62                             (setf reject-reason ',invalid-mb-starter-byte))
  63                           ok))
  64                       (enough-bytes-left-p (x)
  65                         (let ((ok (> end (+ pos (1- x)))))
  66                           (unless ok
  67                             (setf reject-reason 'end-of-input-in-character))
  68                           ok))
  69                       (valid-secondary-p (x)
  70                         (let* ((idx (the array-range (+ pos x)))
  71                                (b (,accessor array idx))
  72                                (ok (,mb-continuation-byte-p b)))
  73                           (unless ok
  74                             (setf reject-reason ',invalid-mb-continuation-byte)
  75                             (setf reject-position idx))
  76                           ok))
  77                       (preliminary-ok-for-length (maybe-len len)
  78                         (and (eql maybe-len len)
  79                              ;; Has to be done in this order so that
  80                              ;; certain broken sequences (e.g., the
  81                              ;; two-byte sequence `"initial (length 3)"
  82                              ;; "non-continuation"' -- `#xef #x32')
  83                              ;; signal only part of that sequence as
  84                              ;; erroneous.
  85                              (loop for i from 1 below (min len remaining-bytes)
  86                                 always (valid-secondary-p i))
  87                              (enough-bytes-left-p len))))
  88                (declare (inline valid-starter-byte-p
  89                                 enough-bytes-left-p
  90                                 valid-secondary-p
  91                                 preliminary-ok-for-length))
  92                (let ((maybe-len (valid-starter-byte-p initial-byte)))
  93                  (cond ((eql maybe-len 1)
  94                         (values 1 nil))
  95                        ((preliminary-ok-for-length maybe-len 2)
  96                         (values 2 nil))
  97                        ((preliminary-ok-for-length maybe-len 3)
  98                         (values 3 nil))
  99                        (t
 100                         (let* ((bad-end (ecase reject-reason
 101                                           (,invalid-mb-starter-byte
 102                                            (1+ pos))
 103                                           (end-of-input-in-character
 104                                            end)
 105                                           (,invalid-mb-continuation-byte
 106                                            reject-position)))
 107                                (bad-len (- bad-end pos)))
 108                           (declare (type array-range bad-end bad-len))
 109                           (let ((replacement (decoding-error array pos bad-end ,format reject-reason reject-position)))
 110                             (values bad-len replacement))))))))))))
 111
 112   (defun define-simple-get-mb-char-1 (accessor type format mb-to-ucs)
 113     (let ((name (make-od-name-list 'simple-get format 'char accessor))
 114           (malformed (make-od-name 'malformed format)))
 115       `(progn
 116          (declaim (inline ,name))
 117          (defun ,name (array pos bytes)
 118            (declare (optimize speed (safety 0))
 119                     (type ,type array)
 120                     (type array-range pos)
 121                     (type (integer 1 3) bytes))
 122            (flet ((cref (x)
 123                     (,accessor array (the array-range (+ pos x)))))
 124              (declare (inline cref))
 125              (let ((code (,mb-to-ucs (ecase bytes
 126                                        (1 (cref 0))
 127                                        (2 (logior (ash (cref 0) 8) (cref 1)))
 128                                        (3 (logior (ash (cref 0) 16)
 129                                                   (ash (cref 1) 8)
 130                                                   (cref 2)))))))
 131                (if code
 132                    (code-char code)
 133                    (decoding-error array pos (+ pos bytes) ,format
 134                                    ',malformed pos))))))))
 135
 136   (defun define-mb->string-1 (accessor type format)
 137     (let ((name
 138            (make-od-name-list format '>string accessor))
 139           (bytes-per-mb-character
 140            (make-od-name-list 'bytes-per format 'character accessor))
 141           (simple-get-mb-char
 142            (make-od-name-list 'simple-get format 'char accessor)))
 143       `(progn
 144          (defun ,name (array astart aend)
 145            (declare (optimize speed (safety 0))
 146                     (type ,type array)
 147                     (type array-range astart aend))
 148            (let ((string (make-array 0 :adjustable t :fill-pointer 0 :element-type 'character)))
 149              (loop with pos = astart
 150                 while (< pos aend)
 151                 do (multiple-value-bind (bytes invalid)
 152                        (,bytes-per-mb-character array pos aend)
 153                      (declare (type (or null string) invalid))
 154                      (cond
 155                        ((null invalid)
 156                         (vector-push-extend (,simple-get-mb-char array pos bytes) string))
 157                        (t
 158                         (dotimes (i (length invalid))
 159                           (vector-push-extend (char invalid i) string))))
 160                      (incf pos bytes)))
 161              (coerce string 'simple-string))))))
 162
 163   (declaim (inline mb-char-len))
 164   (defun mb-char-len (code)
 165     (declare (optimize speed (safety 0))
 166              (type fixnum code))
 167     (cond ((< code 0) (bug "can't happen"))
 168           ((< code #x100) 1)
 169           ((< code #x10000) 2)
 170           ((< code #x1000000) 3)
 171           (t (bug "can't happen"))))
 172   )
 173
 174 (defmacro define-multibyte-encoding (format aliases
 175                                      ucs-to-mb mb-to-ucs
 176                                      mb-len mb-continuation-byte-p)
 177   (let ((char->mb (make-od-name 'char-> format))
 178         (string->mb (make-od-name 'string-> format))
 179         (define-bytes-per-mb-character
 180          (make-od-name-list 'define-bytes-per format 'character))
 181         (define-simple-get-mb-char
 182          (make-od-name-list 'define-simple-get format 'char))
 183         (define-mb->string
 184          (make-od-name-list 'define format '>string)))
 185     `(progn
 186        ;; for fd-stream.lisp
 187        (define-external-format/variable-width ,aliases t
 188          (mb-char-len (or (,ucs-to-mb (char-code byte)) -1))
 189          (let ((mb (,ucs-to-mb bits)))
 190            (if (null mb)
 191                (external-format-encoding-error stream byte)
 192                (ecase size
 193                  (1 (setf (sap-ref-8 sap tail) mb))
 194                  (2 (setf (sap-ref-8 sap tail) (ldb (byte 8 8) mb)
 195                           (sap-ref-8 sap (1+ tail)) (ldb (byte 8 0) mb)))
 196                  (3 (setf (sap-ref-8 sap tail) (ldb (byte 8 16) mb)
 197                           (sap-ref-8 sap (1+ tail)) (ldb (byte 8 8) mb)
 198                           (sap-ref-8 sap (+ 2 tail)) (ldb (byte 8 0) mb))))))
 199          (,mb-len byte)
 200          (let* ((mb (ecase size
 201                       (1 byte)
 202                       (2 (let ((byte2 (sap-ref-8 sap (1+ head))))
 203                            (unless (,mb-continuation-byte-p byte2)
 204                              (return-from decode-break-reason 2))
 205                            (dpb byte (byte 8 8) byte2)))
 206                       (3 (let ((byte2 (sap-ref-8 sap (1+ head)))
 207                                (byte3 (sap-ref-8 sap (+ 2 head))))
 208                            (unless (,mb-continuation-byte-p byte2)
 209                              (return-from decode-break-reason 2))
 210                            (unless (,mb-continuation-byte-p byte3)
 211                              (return-from decode-break-reason 3))
 212                            (dpb byte (byte 8 16) (dpb byte2 (byte 8 8) byte3))))))
 213                 (ucs (,mb-to-ucs mb)))
 214            (if (null ucs)
 215                (return-from decode-break-reason 1)
 216                (code-char ucs))))
 217
 218        ;; for octets.lisp
 219        (define-condition ,(make-od-name 'malformed format)
 220            (octet-decoding-error) ())
 221        (define-condition ,(make-od-name-list 'invalid format 'starter-byte)
 222            (octet-decoding-error) ())
 223        (define-condition ,(make-od-name-list 'invalid format 'continuation-byte)
 224            (octet-decoding-error) ())
 225
 226        (declaim (inline ,char->mb))
 227        (defun ,char->mb (char dest string pos)
 228          (declare (optimize speed (safety 0))
 229                   (type (array (unsigned-byte 8) (*)) dest))
 230          (let ((code (,ucs-to-mb (char-code char))))
 231            (if code
 232                (flet ((add-byte (b)
 233                         (declare (type (unsigned-byte 8) b))
 234                         (vector-push-extend b dest)))
 235                  (declare (inline add-byte))
 236                  (setf code (the fixnum code))
 237                  (ecase (mb-char-len code)
 238                    (1
 239                     (add-byte code))
 240                    (2
 241                     (add-byte (ldb (byte 8 8) code))
 242                     (add-byte (ldb (byte 8 0) code)))
 243                    (3
 244                     (add-byte (ldb (byte 8 16) code))
 245                     (add-byte (ldb (byte 8 8) code))
 246                     (add-byte (ldb (byte 8 0) code)))))
 247                (encoding-error ,format string pos))))
 248
 249        (defun ,string->mb (string sstart send additional-space)
 250          (declare (optimize speed (safety 0))
 251                   (type simple-string string)
 252                   (type array-range sstart send additional-space))
 253          (let ((array (make-array (+ additional-space (- send sstart))
 254                                   :element-type '(unsigned-byte 8)
 255                                   :adjustable t
 256                                   :fill-pointer 0)))
 257            (loop for i from sstart below send
 258               do (,char->mb (char string i) array string i))
 259            (dotimes (i additional-space)
 260              (vector-push-extend 0 array))
 261            (coerce array '(simple-array (unsigned-byte 8) (*)))))
 262
 263        (defmacro ,define-bytes-per-mb-character (accessor type)
 264          (define-bytes-per-mb-character-1 accessor type ',format
 265                                           ',mb-len ',mb-continuation-byte-p))
 266
 267        (instantiate-octets-definition ,define-bytes-per-mb-character)
 268
 269        (defmacro ,define-simple-get-mb-char (accessor type)
 270          (define-simple-get-mb-char-1 accessor type ',format ',mb-to-ucs))
 271
 272        (instantiate-octets-definition ,define-simple-get-mb-char)
 273
 274        (defmacro ,define-mb->string (accessor type)
 275          (define-mb->string-1 accessor type ',format))
 276
 277        (instantiate-octets-definition ,define-mb->string)
 278
 279        (add-external-format-funs ',aliases
 280                                  '(,(make-od-name format '>string-aref)
 281                                    ,string->mb))
 282        )))