Include "coding.h".

(Qget_emacs_mule_file_char, Qload_force_doc_strings,
load_each_byte, unread_char): New variables.
(readchar_backlog): This variable deleted.
(readchar): Return a character unless load_each_byte is nonzero.
Handle the case that readcharfun is Qget_emacs_mule_file_char or a
cons.  If unread_char is not -1, simply return it.
(unreadchar): Handle the case that readcharfun is
Qget_emacs_mule_file_char or a cons.  Set unread_char if
necessary.
(read_multibyte): This function deleted.
(readbyte_for_lambda, readbyte_from_file, readbyte_from_string)
(read_emacs_mule_char): New functions.
(Fload): Even if the file doesn't have the extention ".elc", if
safe_to_load_p returns a positive version number, assume that the
file contains bytecompiled code.  If the version is less than 22,
load the file while decoding multibyte sequences by emacs-mule.
(readevalloop): Don't use readchar_backlog.
(Fread): Likewise.  Pay attention to the case that STREAM is a
cons.
(Fread_from_string): Pay attention to the case that STREAM is a
cons.
(read_escape): The arg BYTEREP deleted.
(read1): Set load_each_byte to 1 temporarily while handling
#@NUMBER.  Don't call read_multibyte.
(read_vector): Call Fread with a cons.  If readcharfun is
Qget_emacs_mule_file_char, decode the read string by emacs-mule.
(read_list): If doc_reference is 2, make the cdr part string as
unibyte.
(syms_of_lread): Intern and staticpro Qget_emacs_mule_file_char
and Qload_force_doc_strings.

1 files changed, 350 insertions, 253 deletions

diff --git a/src/lread.c b/src/lread.c
index b4dc71514d..3d4a639418 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -31,6 +31,7 @@ Boston, MA 02111-1307, USA.  */
 #include "buffer.h"
 #include "character.h"
 #include "charset.h"
+#include "coding.h"
 #include <epaths.h>
 #include "commands.h"
 #include "keyboard.h"
@@ -83,6 +84,12 @@ Lisp_Object Qascii_character, Qload, Qload_file_name;
 Lisp_Object Qbackquote, Qcomma, Qcomma_at, Qcomma_dot, Qfunction;
 Lisp_Object Qinhibit_file_name_operation;
 
+/* Used instead of Qget_file_char while loading *.elc files compiled
+   by Emacs 21 or older.  */
+static Lisp_Object Qget_emacs_mule_file_char;
+
+static Lisp_Object Qload_force_doc_strings;
+
 extern Lisp_Object Qevent_symbol_element_mask;
 extern Lisp_Object Qfile_exists_p;
 
@@ -126,6 +133,11 @@ static int load_force_doc_strings;
 /* Nonzero means read should convert strings to unibyte.  */
 static int load_convert_to_unibyte;
 
+/* Nonzero means READCHAR should read bytes one by one (not character)
+   when READCHARFUN is Qget_file_char or Qget_emacs_mule_file_char.
+   This is set to 1 by read1 temporarily while handling #@NUMBER.  */
+static int load_each_byte;
+
 /* Function to use for loading an Emacs lisp source file (not
    compiled) instead of readevalloop.  */
 Lisp_Object Vload_source_file_function;
@@ -147,10 +159,6 @@ static int read_from_string_index;
 static int read_from_string_index_byte;
 static int read_from_string_limit;
 
-/* Number of bytes left to read in the buffer character
-   that `readchar' has already advanced over.  */
-static int readchar_backlog;
-
 /* This contains the last string skipped with #@.  */
 static char *saved_doc_string;
 /* Length of buffer allocated in saved_doc_string.  */
@@ -190,6 +198,9 @@ int load_dangerous_libraries;
 
 static Lisp_Object Vbytecomp_version_regexp;
 
+static int read_emacs_mule_char P_ ((int, int (*) (int, Lisp_Object),
+				     Lisp_Object));
+
 static void readevalloop P_ ((Lisp_Object, FILE*, Lisp_Object, 
 			      Lisp_Object (*) (), int,
 			      Lisp_Object, Lisp_Object));
@@ -197,23 +208,42 @@ static Lisp_Object load_unwind P_ ((Lisp_Object));
 static Lisp_Object load_descriptor_unwind P_ ((Lisp_Object));
 
 
+/* Functions that read one byte from the current source READCHARFUN
+   or unreads one byte.  If the integer argument C is -1, it returns
+   one read byte, or -1 when there's no more byte in the source.  If C
+   is 0 or positive, it unreads C, and the return value is not
+   interesting.  */
+
+static int readbyte_for_lambda P_ ((int, Lisp_Object));
+static int readbyte_from_file P_ ((int, Lisp_Object));
+static int readbyte_from_string P_ ((int, Lisp_Object));
+
 /* Handle unreading and rereading of characters.
    Write READCHAR to read a character,
    UNREAD(c) to unread c to be read again.
 
-   These macros actually read/unread a byte code, multibyte characters
-   are not handled here.  The caller should manage them if necessary.
- */
+   These macros correctly read/unread multibyte characters.  */
 
 #define READCHAR readchar (readcharfun)
 #define UNREAD(c) unreadchar (readcharfun, c)
 
+/* When READCHARFUN is Qget_file_char, Qget_emacs_mule_file_char,
+   Qlambda, or a cons, we use this to keep unread character because a
+   file stream can't handle multibyte-char unreading.  The value -1
+   means that there's no unread character. */
+static int unread_char;
+
+
 static int
 readchar (readcharfun)
      Lisp_Object readcharfun;
 {
   Lisp_Object tem;
   register int c;
+  int (*readbyte) P_ ((int, Lisp_Object));
+  unsigned char buf[MAX_MULTIBYTE_LENGTH];
+  int i, len;
+  int emacs_mule_encoding = 0;
 
   if (BUFFERP (readcharfun))
     {
@@ -221,19 +251,9 @@ readchar (readcharfun)
 
       int pt_byte = BUF_PT_BYTE (inbuffer);
 
-      if (readchar_backlog > 0)
-	/* We get the address of the byte just passed,
-	   which is the last byte of the character.
-	   The other bytes in this character are consecutive with it,
-	   because the gap can't be in the middle of a character.  */
-	return *(BUF_BYTE_ADDRESS (inbuffer, BUF_PT_BYTE (inbuffer) - 1)
-		 - --readchar_backlog);
-
       if (pt_byte >= BUF_ZV_BYTE (inbuffer))
 	return -1;
 
-      readchar_backlog = -1;
-
       if (! NILP (inbuffer->enable_multibyte_characters))
 	{
 	  /* Fetch the character code from the buffer.  */
@@ -244,6 +264,8 @@ readchar (readcharfun)
       else
 	{
 	  c = BUF_FETCH_BYTE (inbuffer, pt_byte);
+	  if (! ASCII_BYTE_P (c))
+	    c = BYTE8_TO_CHAR (c);
 	  pt_byte++;
 	}
       SET_BUF_PT_BOTH (inbuffer, BUF_PT (inbuffer) + 1, pt_byte);
@@ -256,19 +278,9 @@ readchar (readcharfun)
 
       int bytepos = marker_byte_position (readcharfun);
 
-      if (readchar_backlog > 0)
-	/* We get the address of the byte just passed,
-	   which is the last byte of the character.
-	   The other bytes in this character are consecutive with it,
-	   because the gap can't be in the middle of a character.  */
-	return *(BUF_BYTE_ADDRESS (inbuffer, XMARKER (readcharfun)->bytepos - 1)
-		 - --readchar_backlog);
-
       if (bytepos >= BUF_ZV_BYTE (inbuffer))
 	return -1;
 
-      readchar_backlog = -1;
-
       if (! NILP (inbuffer->enable_multibyte_characters))
 	{
 	  /* Fetch the character code from the buffer.  */
@@ -279,6 +291,8 @@ readchar (readcharfun)
       else
 	{
 	  c = BUF_FETCH_BYTE (inbuffer, bytepos);
+	  if (! ASCII_BYTE_P (c))
+	    c = BYTE8_TO_CHAR (c);
 	  bytepos++;
 	}
 
@@ -289,22 +303,15 @@ readchar (readcharfun)
     }
 
   if (EQ (readcharfun, Qlambda))
-    return read_bytecode_char (0);
-
+    {
+      readbyte = readbyte_for_lambda;
+      goto read_multibyte;
+    }
   if (EQ (readcharfun, Qget_file_char))
     {
-      c = getc (instream);
-#ifdef EINTR
-      /* Interrupted reads have been observed while reading over the network */
-      while (c == EOF && ferror (instream) && errno == EINTR)
-	{
-	  clearerr (instream);
-	  c = getc (instream);
-	}
-#endif
-      return c;
+      readbyte = readbyte_from_file;
+      goto read_multibyte;
     }
-
   if (STRINGP (readcharfun))
     {
       if (read_from_string_index >= read_from_string_limit)
@@ -316,14 +323,61 @@ readchar (readcharfun)
 
       return c;
     }
+  if (CONSP (readcharfun))
+    {
+      /* This is the case that read_vector is reading from a unibyte
+	 string that contains a byte sequence previously skipped
+	 because of #@NUMBER.  The car part of readcharfun is that
+	 string, and the cdr part is a value of readcharfun given to
+	 read_vector.  */
+      readbyte = readbyte_from_string;
+      if (EQ (XCDR (readcharfun), Qget_emacs_mule_file_char))
+	emacs_mule_encoding = 1;
+      goto read_multibyte;
+    }
+  if (EQ (readcharfun, Qget_emacs_mule_file_char))
+    {
+      readbyte = readbyte_from_file;
+      emacs_mule_encoding = 1;
+      goto read_multibyte;
+    }
 
   tem = call0 (readcharfun);
 
   if (NILP (tem))
     return -1;
   return XINT (tem);
+
+ read_multibyte:
+  if (unread_char >= 0)
+    {
+      c = unread_char;
+      unread_char = -1;
+      return c;
+    }
+  c = (*readbyte) (-1, readcharfun);
+  if (c < 0 || ASCII_BYTE_P (c) || load_each_byte)
+    return c;
+  if (emacs_mule_encoding)
+    return read_emacs_mule_char (c, readbyte, readcharfun);
+  i = 0;
+  buf[i++] = c;
+  len = BYTES_BY_CHAR_HEAD (c);
+  while (i < len)
+    {
+      c = (*readbyte) (-1, readcharfun);
+      if (c < 0 || ! TRAILING_CODE_P (c))
+	{
+	  while (--i > 1)
+	    (*readbyte) (buf[i], readcharfun);
+	  return BYTE8_TO_CHAR (buf[0]);
+	}
+      buf[i++] = c;
+    }
+  return STRING_CHAR (buf, i);
 }
 
+
 /* Unread the character C in the way appropriate for the stream READCHARFUN.
    If the stream is a user function, call it with the char as argument.  */
 
@@ -341,36 +395,26 @@ unreadchar (readcharfun, c)
       struct buffer *b = XBUFFER (readcharfun);
       int bytepos = BUF_PT_BYTE (b);
 
-      if (readchar_backlog >= 0)
-	readchar_backlog++;
+      BUF_PT (b)--;
+      if (! NILP (b->enable_multibyte_characters))
+	BUF_DEC_POS (b, bytepos);
       else
-	{
-	  BUF_PT (b)--;
-	  if (! NILP (b->enable_multibyte_characters))
-	    BUF_DEC_POS (b, bytepos);
-	  else
-	    bytepos--;
+	bytepos--;
 
-	  BUF_PT_BYTE (b) = bytepos;
-	}
+      BUF_PT_BYTE (b) = bytepos;
     }
   else if (MARKERP (readcharfun))
     {
       struct buffer *b = XMARKER (readcharfun)->buffer;
       int bytepos = XMARKER (readcharfun)->bytepos;
 
-      if (readchar_backlog >= 0)
-	readchar_backlog++;
+      XMARKER (readcharfun)->charpos--;
+      if (! NILP (b->enable_multibyte_characters))
+	BUF_DEC_POS (b, bytepos);
       else
-	{
-	  XMARKER (readcharfun)->charpos--;
-	  if (! NILP (b->enable_multibyte_characters))
-	    BUF_DEC_POS (b, bytepos);
-	  else
-	    bytepos--;
+	bytepos--;
 
-	  XMARKER (readcharfun)->bytepos = bytepos;
-	}
+      XMARKER (readcharfun)->bytepos = bytepos;
     }
   else if (STRINGP (readcharfun))
     {
@@ -378,16 +422,152 @@ unreadchar (readcharfun, c)
       read_from_string_index_byte
 	= string_char_to_byte (readcharfun, read_from_string_index);
     }
+  else if (CONSP (readcharfun))
+    {
+      unread_char = c;
+    }
   else if (EQ (readcharfun, Qlambda))
-    read_bytecode_char (1);
-  else if (EQ (readcharfun, Qget_file_char))
-    ungetc (c, instream);
+    {
+      unread_char = c;
+    }
+  else if (EQ (readcharfun, Qget_file_char)
+	   || EQ (readcharfun, Qget_emacs_mule_file_char))
+    {
+      if (load_each_byte)
+	ungetc (c, instream);
+      else
+	unread_char = c;
+    }
   else
     call1 (readcharfun, make_number (c));
 }
 
+static int
+readbyte_for_lambda (c, readcharfun)
+     int c;
+     Lisp_Object readcharfun;
+{
+  return read_bytecode_char (c >= 0);
+}
+
+
+static int
+readbyte_from_file (c, readcharfun)
+     int c;
+     Lisp_Object readcharfun;
+{
+  if (c >= 0)
+    {
+      ungetc (c, instream);
+      return 0;
+    }
+
+  c = getc (instream);
+#ifdef EINTR
+  /* Interrupted reads have been observed while reading over the network */
+  while (c == EOF && ferror (instream) && errno == EINTR)
+    {
+      clearerr (instream);
+      c = getc (instream);
+    }
+#endif
+  return (c == EOF ? -1 : c);
+}
+
+static int
+readbyte_from_string (c, readcharfun)
+     int c;
+     Lisp_Object readcharfun;
+{
+  Lisp_Object string = XCAR (readcharfun);
+
+  if (c >= 0)
+    {
+      read_from_string_index--;
+      read_from_string_index_byte
+	= string_char_to_byte (string, read_from_string_index);
+    }
+  
+  if (read_from_string_index >= read_from_string_limit)
+    c = -1;
+  else
+    FETCH_STRING_CHAR_ADVANCE (c, string,
+			       read_from_string_index,
+			       read_from_string_index_byte);
+  return c;
+}
+
+
+/* Read one non-ASCII character from INSTREAM.  The character is
+   encoded in `emacs-mule' and the first byte is already read in
+   C.  */
+
+extern char emacs_mule_bytes[256];
+
+static int
+read_emacs_mule_char (c, readbyte, readcharfun)
+     int c;
+     int (*readbyte) P_ ((int, Lisp_Object));
+     Lisp_Object readcharfun;
+{
+  /* Emacs-mule coding uses at most 4-byte for one character.  */
+  unsigned char buf[4];
+  int len = emacs_mule_bytes[c];
+  struct charset *charset;
+  int i;
+  unsigned code;
+
+  if (len == 1)
+    /* C is not a valid leading-code of `emacs-mule'.  */
+    return BYTE8_TO_CHAR (c);
+
+  i = 0;
+  buf[i++] = c;
+  while (i < len)
+    {
+      c = (*readbyte) (-1, readcharfun);
+      if (c < 0xA0)
+	{
+	  while (--i > 1)
+	    (*readbyte) (buf[i], readcharfun);
+	  return BYTE8_TO_CHAR (buf[0]);
+	}
+      buf[i++] = c;
+    }
+
+  if (len == 2)
+    {
+      charset = emacs_mule_charset[c];
+      code = buf[1] & 0x7F;
+    }
+  else if (len == 3)
+    {
+      if (buf[0] == EMACS_MULE_LEADING_CODE_PRIVATE_11
+	  || buf[0] == EMACS_MULE_LEADING_CODE_PRIVATE_12)
+	{
+	  charset = emacs_mule_charset[buf[1]];
+	  code = buf[2] & 0x7F;
+	}
+      else
+	{
+	  charset = emacs_mule_charset[buf[0]];
+	  code = ((buf[1] << 8) | buf[2]) & 0x7F7F;
+	}
+    }
+  else
+    {
+      charset = emacs_mule_charset[buf[1]];
+      code = ((buf[2] << 8) | buf[3]) & 0x7F7F;      
+    }
+  c = DECODE_CHAR (charset, code);
+  if (c < 0)
+    Fsignal (Qinvalid_read_syntax,
+	     Fcons (build_string ("invalid multibyte form"), Qnil));
+  return c;
+}
+
+
 static Lisp_Object read0 (), read1 (), read_list (), read_vector ();
-static int read_multibyte ();
 static Lisp_Object substitute_object_recurse ();
 static void        substitute_object_in_subtree (), substitute_in_interval ();
 
@@ -553,11 +733,11 @@ DEFUN ("get-file-char", Fget_file_char, Sget_file_char, 0, 0, 0,
 
 
 
-/* Value is non-zero if the file asswociated with file descriptor FD
-   is a compiled Lisp file that's safe to load.  Only files compiled
-   with Emacs are safe to load.  Files compiled with XEmacs can lead
-   to a crash in Fbyte_code because of an incompatible change in the
-   byte compiler.  */
+/* Value is a version number of byte compiled code if the file
+   associated with file descriptor FD is a compiled Lisp file that's
+   safe to load.  Only files compiled with Emacs are safe to load.
+   Files compiled with XEmacs can lead to a crash in Fbyte_code
+   because of an incompatible change in the byte compiler.  */
 
 static int
 safe_to_load_p (fd)
@@ -578,7 +758,7 @@ safe_to_load_p (fd)
 	 with NUL bytes following it, but note the version.  */
       for (i = 0; i < nbytes && buf[i] != '\n'; ++i)
 	if (i == 4)
-          version = buf[i];
+	  version = buf[i];
 
       if (i < nbytes
 	  && fast_c_string_match_ignore_case (Vbytecomp_version_regexp,
@@ -637,6 +817,8 @@ Return t if file exists.  */)
   Lisp_Object handler;
   int safe_p = 1;
   char *fmode = "r";
+  int version;
+
 #ifdef DOS_NT
   fmode = "rt";
 #endif /* DOS_NT */
@@ -744,17 +926,20 @@ Return t if file exists.  */)
     Vloads_in_progress = Fcons (found, Vloads_in_progress);
   }
 
+  version = -1;
   if (!bcmp (&(XSTRING (found)->data[STRING_BYTES (XSTRING (found)) - 4]),
-	     ".elc", 4))
+	     ".elc", 4)
+      || (version = safe_to_load_p (fd)) > 0)
     /* Load .elc files directly, but not when they are
        remote and have no handler!  */
     {
       if (fd != -2)
 	{
 	  struct stat s1, s2;
-	  int result, version;
+	  int result;
 
-	  if (!(version = safe_to_load_p (fd)))
+	  if (version < 0
+	      && ! (version = safe_to_load_p (fd)))
 	    {
 	      safe_p = 0;
 	      if (!load_dangerous_libraries)
@@ -769,30 +954,6 @@ Return t if file exists.  */)
 
 	  compiled = 1;
 
-	  if (version == 20)	/* 21 isn't used */
-	    /* We're loading something compiled with Mule 3, 4 or 5,
-	       and thus potentially emacs-mule-encoded; load it with
-	       code conversion.  (Perhaps the test should actually be
-	       <22?)  We could check further on whether the comment
-	       mentions multibyte and only code-convert if it does.  I
-	       doubt it's worth the effort. -- fx  */
-	    {
-	      Lisp_Object val;
-
-	      if (fd >= 0)
-		emacs_close (fd);
-	      /* load-with-code-conversion currently fails with
-		 emacs-mule non-ASCII doc strings.  */
-	      error ("Can't currently load Emacs 20/1-compiled files: %s",
-		     XSTRING (found)->data);
-#if 0
-	      val = call4 (intern ("load-with-code-conversion"), found, file,
-			   NILP (noerror) ? Qnil : Qt,
-			   NILP (nomessage) ? Qnil : Qt);
-#endif
-	      return unbind_to (count, val);
-	    }
-
 #ifdef DOS_NT
 	  fmode = "rb";
 #endif /* DOS_NT */
@@ -868,7 +1029,16 @@ Return t if file exists.  */)
   load_descriptor_list
     = Fcons (make_number (fileno (stream)), load_descriptor_list);
   load_in_progress++;
-  readevalloop (Qget_file_char, stream, file, Feval, 0, Qnil, Qnil);
+  if (version >= 22)
+    readevalloop (Qget_file_char, stream, file, Feval, 0, Qnil, Qnil);
+  else
+    {
+      /* We can't handle a file which was compiled with
+	 byte-compile-dynamic by older version of Emacs.  */
+      specbind (Qload_force_doc_strings, Qt);
+      readevalloop (Qget_emacs_mule_file_char, stream, file, Feval, 0,
+		    Qnil, Qnil);
+    }
   unbind_to (count, Qnil);
 
   /* Run any load-hooks for this file.  */
@@ -1242,8 +1412,6 @@ readevalloop (readcharfun, stream, sourcename, evalfun, printflag, unibyte, read
   record_unwind_protect (readevalloop_1, load_convert_to_unibyte ? Qt : Qnil);
   load_convert_to_unibyte = !NILP (unibyte);
 
-  readchar_backlog = -1;
-
   GCPRO1 (sourcename);
 
   LOADHIST_ATTACH (sourcename);
@@ -1423,14 +1591,13 @@ STREAM or the value of `standard-input' may be:
   if (EQ (stream, Qt))
     stream = Qread_char;
 
-  readchar_backlog = -1;
   new_backquote_flag = 0;
   read_objects = Qnil;
 
   if (EQ (stream, Qread_char))
     return Fread_minibuffer (build_string ("Lisp expression: "), Qnil);
 
-  if (STRINGP (stream))
+  if (STRINGP (stream) || ((CONSP (stream) && STRINGP (XCAR (stream)))))
     return Fcar (Fread_from_string (stream, Qnil, Qnil));
 
   return read0 (stream);
@@ -1445,18 +1612,23 @@ START and END optionally delimit a substring of STRING from which to read;
      Lisp_Object string, start, end;
 {
   int startval, endval;
+  Lisp_Object str;
   Lisp_Object tem;
 
-  CHECK_STRING (string);
+  if (CONSP (string))
+    str = XCAR (string);
+  else
+    str = string;
+  CHECK_STRING (str);
 
   if (NILP (end))
-    endval = XSTRING (string)->size;
+    endval = XSTRING (str)->size;
   else
     {
       CHECK_NUMBER (end);
       endval = XINT (end);
-      if (endval < 0 || endval > XSTRING (string)->size)
-	args_out_of_range (string, end);
+      if (endval < 0 || endval > XSTRING (str)->size)
+	args_out_of_range (str, end);
     }
 
   if (NILP (start))
@@ -1466,11 +1638,11 @@ START and END optionally delimit a substring of STRING from which to read;
       CHECK_NUMBER (start);
       startval = XINT (start);
       if (startval < 0 || startval > endval)
-	args_out_of_range (string, start);
+	args_out_of_range (str, start);
     }
 
   read_from_string_index = startval;
-  read_from_string_index_byte = string_char_to_byte (string, startval);
+  read_from_string_index_byte = string_char_to_byte (str, startval);
   read_from_string_limit = endval;
 
   new_backquote_flag = 0;
@@ -1502,65 +1674,16 @@ read0 (readcharfun)
 static int read_buffer_size;
 static char *read_buffer;
 
-/* Read multibyte form and return it as a character.  C is a first
-   byte of multibyte form, and rest of them are read from
-   READCHARFUN.  Store the byte length of the form into *NBYTES.  */
-
-static int
-read_multibyte (c, readcharfun, nbytes)
-     register int c;
-     Lisp_Object readcharfun;
-     int *nbytes;
-{
-  /* We need the actual character code of this multibyte
-     characters.  */
-  unsigned char str[MAX_MULTIBYTE_LENGTH];
-  int len = 0;
-  int bytes = BYTES_BY_CHAR_HEAD (c);
-
-  str[len++] = c;
-  while (len < bytes)
-    {
-      c = READCHAR;
-      if (CHAR_HEAD_P (c))
-	{
-	  UNREAD (c);
-	  break;
-	}
-      str[len++] = c;
-    }
-
-  if (len == bytes && MULTIBYTE_LENGTH_NO_CHECK (str) > 0)
-    {
-      *nbytes = len;
-      return STRING_CHAR (str, len);
-    }
-  /* The byte sequence is not valid as multibyte.  Unread all bytes
-     but the first one, and return the first byte.  */
-  while (--len > 0)
-    UNREAD (str[len]);
-  *nbytes = 1;
-  return str[0];
-}
-
 /* Read a \-escape sequence, assuming we already read the `\'.
-   If the escape sequence forces unibyte, store 1 into *BYTEREP.
-   If the escape sequence forces multibyte and the returned character
-   is raw 8-bit char, store 2 into *BYTEREP.
-   If the escape sequence forces multibyte and the returned character
-   is not raw 8-bit char, store 3 into *BYTEREP.
-   Otherwise store 0 into *BYTEREP.  */
+   If the escape sequence forces unibyte, return eight-bit-char.  */
 
 static int
-read_escape (readcharfun, stringp, byterep)
+read_escape (readcharfun, stringp)
      Lisp_Object readcharfun;
      int stringp;
-     int *byterep;
 {
   register int c = READCHAR;
 
-  *byterep = 0;
-
   switch (c)
     {
     case -1:
@@ -1597,7 +1720,7 @@ read_escape (readcharfun, stringp, byterep)
 	error ("Invalid escape character syntax");
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       return c | meta_modifier;
 
     case 'S':
@@ -1606,7 +1729,7 @@ read_escape (readcharfun, stringp, byterep)
 	error ("Invalid escape character syntax");
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       return c | shift_modifier;
 
     case 'H':
@@ -1615,7 +1738,7 @@ read_escape (readcharfun, stringp, byterep)
 	error ("Invalid escape character syntax");
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       return c | hyper_modifier;
 
     case 'A':
@@ -1624,7 +1747,7 @@ read_escape (readcharfun, stringp, byterep)
 	error ("Invalid escape character syntax");
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       return c | alt_modifier;
 
     case 's':
@@ -1633,7 +1756,7 @@ read_escape (readcharfun, stringp, byterep)
 	error ("Invalid escape character syntax");
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       return c | super_modifier;
 
     case 'C':
@@ -1643,7 +1766,7 @@ read_escape (readcharfun, stringp, byterep)
     case '^':
       c = READCHAR;
       if (c == '\\')
-	c = read_escape (readcharfun, 0, byterep);
+	c = read_escape (readcharfun, 0);
       if ((c & ~CHAR_MODIFIER_MASK) == '?')
 	return 0177 | (c & CHAR_MODIFIER_MASK);
       else if (! SINGLE_BYTE_CHAR_P ((c & ~CHAR_MODIFIER_MASK)))
@@ -1683,10 +1806,8 @@ read_escape (readcharfun, stringp, byterep)
 	      }
 	  }
 	
-	if (c < 0x100)
-	  *byterep = 1;
-	else
-	  *byterep = 3;
+	if (! ASCII_BYTE_P (i))
+	  i = BYTE8_TO_CHAR (i);
 	return i;
       }
 
@@ -1721,22 +1842,11 @@ read_escape (readcharfun, stringp, byterep)
 	  }
 
 	if (count < 3 && i >= 0x80)
-	  *byterep = 2;
-	else
-	  *byterep = 3;
+	  return BYTE8_TO_CHAR (i);
 	return i;
       }
 
     default:
-      if (EQ (readcharfun, Qget_file_char)
-	  && BASE_LEADING_CODE_P (c))
-	{
-	  int nbytes;
-
-	  c = read_multibyte (c, readcharfun, &nbytes);
-	  if (nbytes > 1)
-	    *byterep = 3;
-	}
       return c;
     }
 }
@@ -1824,6 +1934,7 @@ read1 (readcharfun, pch, first_in_list)
   int uninterned_symbol = 0;
 
   *pch = 0;
+  load_each_byte = 0;
 
  retry:
 
@@ -1898,12 +2009,14 @@ read1 (readcharfun, pch, first_in_list)
 
 	      UNREAD (c);
 	      tmp = read1 (readcharfun, pch, first_in_list);
-	      if (size_in_chars != XSTRING (tmp)->size
-		  /* We used to print 1 char too many
-		     when the number of bits was a multiple of 8.
-		     Accept such input in case it came from an old version.  */
-		  && ! (XFASTINT (length)
-			== (XSTRING (tmp)->size - 1) * BITS_PER_CHAR))
+	      if (STRING_MULTIBYTE (tmp)
+		  || (size_in_chars != XSTRING (tmp)->size
+		      /* We used to print 1 char too many
+			 when the number of bits was a multiple of 8.
+			 Accept such input in case it came from an old
+			 version.  */
+		      && ! (XFASTINT (length)
+			    == (XSTRING (tmp)->size - 1) * BITS_PER_CHAR)))
 		Fsignal (Qinvalid_read_syntax,
 			 Fcons (make_string ("#&...", 5), Qnil));
 		
@@ -1969,6 +2082,7 @@ read1 (readcharfun, pch, first_in_list)
 	{
 	  int i, nskip = 0;
 
+	  load_each_byte = 1;
 	  /* Read a decimal integer.  */
 	  while ((c = READCHAR) >= 0
 		 && c >= '0' && c <= '9')
@@ -1979,7 +2093,9 @@ read1 (readcharfun, pch, first_in_list)
 	  if (c >= 0)
 	    UNREAD (c);
 	  
-	  if (load_force_doc_strings && EQ (readcharfun, Qget_file_char))
+	  if (load_force_doc_strings
+	      && (EQ (readcharfun, Qget_file_char)
+		  || EQ (readcharfun, Qget_emacs_mule_file_char)))
 	    {
 	      /* If we are supposed to force doc strings into core right now,
 		 record the last string that we skipped,
@@ -2031,6 +2147,7 @@ read1 (readcharfun, pch, first_in_list)
 		c = READCHAR;
 	    }
 
+	  load_each_byte = 0;
 	  goto retry;
 	}
       if (c == '$')
@@ -2152,17 +2269,18 @@ read1 (readcharfun, pch, first_in_list)
 
     case '?':
       {
-	int discard;
+	int modifiers;
 
 	c = READCHAR;
 	if (c < 0)
 	  end_of_file_error ();
-
 	if (c == '\\')
-	  c = read_escape (readcharfun, 0, &discard);
-	else if (EQ (readcharfun, Qget_file_char)
-		 && BASE_LEADING_CODE_P (c))
-	  c = read_multibyte (c, readcharfun, &discard);
+	  c = read_escape (readcharfun, 0);
+	modifiers = c & CHAR_MODIFIER_MASK;
+	c &= ~CHAR_MODIFIER_MASK;
+	if (CHAR_BYTE8_P (c))
+	  c = CHAR_TO_BYTE8 (c);
+	c |= modifiers;
 
 	return make_number (c);
       }
@@ -2196,9 +2314,8 @@ read1 (readcharfun, pch, first_in_list)
 	    if (c == '\\')
 	      {
 		int modifiers;
-		int byterep;
 
-		c = read_escape (readcharfun, 1, &byterep);
+		c = read_escape (readcharfun, 1);
 
 		/* C is -1 if \ newline has just been seen */
 		if (c == -1)
@@ -2211,26 +2328,11 @@ read1 (readcharfun, pch, first_in_list)
 		modifiers = c & CHAR_MODIFIER_MASK;
 		c = c & ~CHAR_MODIFIER_MASK;
 
-		if (byterep == 1)
-		  {
-		    force_singlebyte = 1;
-		    if (c >= 0x80)
-		      /*  Raw 8-bit code */
-		      c = BYTE8_TO_CHAR (c);
-		  }
-		else if (byterep > 1)
-		  {
-		    force_multibyte = 1;
-		    if (byterep == 2)
-		      c = BYTE8_TO_CHAR (c);
-		  }
-		else if (c >= 0x80)
-		  {
-		    force_singlebyte = 1;
-		    c = BYTE8_TO_CHAR (c);
-		  }
-
-		if (ASCII_CHAR_P (c))
+		if (CHAR_BYTE8_P (c))
+		  force_singlebyte = 1;
+		else if (! ASCII_CHAR_P (c))
+		  force_multibyte = 1;
+		else		/* i.e. ASCII_CHAR_P (c) */
 		  {
 		    /* Allow `\C- ' and `\C-?'.  */
 		    if (modifiers == CHAR_CTL)
@@ -2264,34 +2366,10 @@ read1 (readcharfun, pch, first_in_list)
 		  error ("Invalid modifier in string");
 		p += CHAR_STRING (c, (unsigned char *) p);
 	      }
-	    else if (c >= 0x80)
+	    else
 	      {
-		if (EQ (readcharfun, Qget_file_char))
-		  {
-		    if (BASE_LEADING_CODE_P (c))
-		      {
-			int nbytes;
-			c = read_multibyte (c, readcharfun, &nbytes);
-			if (nbytes > 1)
-			  force_multibyte = 1;
-			else
-			  {
-			    force_singlebyte = 1;
-			    c = BYTE8_TO_CHAR (c);
-			  }
-		      }
-		    else
-		      {
-			force_singlebyte = 1;
-			c = BYTE8_TO_CHAR (c);
-		      }
-		  }
-		else
-		  force_multibyte = 1;
 		p += CHAR_STRING (c, (unsigned char *) p);
 	      }
-	    else
-	      *p++ = c;
 	    nchars++;
 	  }
 	if (c < 0)
@@ -2371,11 +2449,7 @@ read1 (readcharfun, pch, first_in_list)
 		  quoted = 1;
 		}
 
-	      if (! SINGLE_BYTE_CHAR_P (c))
-		p += CHAR_STRING (c, p);
-	      else
-		*p++ = c;
-
+	      p += CHAR_STRING (c, p);
 	      c = READCHAR;
 	    }
 
@@ -2702,7 +2776,7 @@ read_vector (readcharfun, bytecodeflag)
 		  XSTRING (bytestr)->size = STRING_BYTES (XSTRING (bytestr));
 		  SET_STRING_BYTES (XSTRING (bytestr), -1);
 
-		  item = Fread (bytestr);
+		  item = Fread (Fcons (bytestr, readcharfun));
 		  if (!CONSP (item))
 		    error ("invalid byte code");
 
@@ -2715,6 +2789,15 @@ read_vector (readcharfun, bytecodeflag)
 	      /* Now handle the bytecode slot.  */
 	      ptr[COMPILED_BYTECODE] = read_pure ? Fpurecopy (bytestr) : bytestr;
 	    }
+	  else if (i == COMPILED_DOC_STRING
+		   && STRINGP (item)
+		   && ! STRING_MULTIBYTE (item))
+	    {
+	      if (EQ (readcharfun, Qget_emacs_mule_file_char))
+		item = Fdecode_coding_string (item, Qemacs_mule, Qnil, Qnil);
+	      else
+		item = Fstring_as_multibyte (item);
+	    }
 	}
       ptr[i] = read_pure ? Fpurecopy (item) : item;
       otem = XCONS (tem);
@@ -2812,7 +2895,14 @@ read_list (flag, readcharfun)
 		  if (doc_reference == 2)
 		    {
 		      /* Get a doc string from the file we are loading.
-			 If it's in saved_doc_string, get it from there.  */
+			 If it's in saved_doc_string, get it from there.
+
+			 Here, we don't know if the string is a
+			 bytecode string or a doc string.  As a
+			 bytecode string must be unibyte, we always
+			 return a unibyte string.  If it is actually a
+			 doc string, caller must make it
+			 multibyte.  */
 		      int pos = XINT (XCDR (val));
 		      /* Position is negative for user variables.  */
 		      if (pos < 0) pos = -pos;
@@ -2844,8 +2934,8 @@ read_list (flag, readcharfun)
 				saved_doc_string[to++] = c;
 			    }
 
-			  return make_string (saved_doc_string + start,
-					      to - start);
+			  return make_unibyte_string (saved_doc_string + start,
+						      to - start);
 			}
 		      /* Look in prev_saved_doc_string the same way.  */
 		      else if (pos >= prev_saved_doc_string_position
@@ -2876,11 +2966,12 @@ read_list (flag, readcharfun)
 				prev_saved_doc_string[to++] = c;
 			    }
 
-			  return make_string (prev_saved_doc_string + start,
-					      to - start);
+			  return make_unibyte_string (prev_saved_doc_string
+						      + start,
+						      to - start);
 			}
 		      else
-			return get_doc_string (val, 0, 0);
+			return get_doc_string (val, 1, 0);
 		    }
 
 		  return val;
@@ -3764,6 +3855,12 @@ to load.  See also `load-dangerous-libraries'.  */);
   Qget_file_char = intern ("get-file-char");
   staticpro (&Qget_file_char);
 
+  Qget_emacs_mule_file_char = intern ("get-emacs-mule-file-char");
+  staticpro (&Qget_emacs_mule_file_char);
+
+  Qload_force_doc_strings = intern ("load-force-doc-strings");
+  staticpro (&Qload_force_doc_strings);
+
   Qbackquote = intern ("`");
   staticpro (&Qbackquote);
   Qcomma = intern (",");