(Vset_auto_coding_function): Name changed from

Vauto_file_coding_system.
(syms_of_fileio): Adjusted for the above change.  Doc-string
modified.
(Finsert_file_contents): The argument for Vset_auto_coding is a
concatination of the heading 1K-byte and the tailing 3K-byte.

diff --git a/src/fileio.c b/src/fileio.c
index d8164d64dc8c0aeb024d8e8df48c3639f8999dcd..5502ebf0d310c87e72b53fce71942e95421a1982 100644 (file)
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -170,7 +170,7 @@ Lisp_Object Vauto_save_file_format;
 Lisp_Object Qformat_decode, Qformat_annotate_function;
 
 /* Function to be called to decide a coding system of a reading file.  */
-Lisp_Object Vauto_file_coding_system_function;
+Lisp_Object Vset_auto_coding_function;
 
 /* Functions to be called to process text properties in inserted file.  */
 Lisp_Object Vafter_insert_file_functions;
@@ -3149,20 +3149,35 @@ This does code conversion according to the value of\n\
       val = Qemacs_mule;
     else
       {
-       if (SYMBOLP (Vauto_file_coding_system_function)
-           && !NILP (Fboundp (Vauto_file_coding_system_function)))
+       if (SYMBOLP (Vset_auto_coding_function)
+           && !NILP (Fboundp (Vset_auto_coding_function)))
          {
-           /* Find a coding system specified in a few lines at the
-              head of the file.  We assume that the fist 1K bytes is
-              sufficient fot this purpose.  */
-           int nread = read (fd, read_buf, 1024);
+           /* Find a coding system specified in the heading two lines
+              or in the tailing several lines of the file.  We assume
+              that the 1K-byte and 3K-byte for heading and tailing
+              respectively are sufficient fot this purpose.  */
+           int how_many, nread;
+
+           if (st.st_size <= (1024 * 4))
+             nread = read (fd, read_buf, 1024 * 4);
+           else
+             {
+               nread = read (fd, read_buf, 1024);
+               if (nread >= 0)
+                 {
+                   if (lseek (fd, st.st_size - (1024 * 3), 0) < 0)
+                     report_file_error ("Setting file position",
+                                        Fcons (filename, Qnil));
+                   nread += read (fd, read_buf + nread, 1024 * 3);
+                 }
+             }
         
            if (nread < 0)
              error ("IO error reading %s: %s",
                     XSTRING (filename)->data, strerror (errno));
            else if (nread > 0)
              {
-               val = call1 (Vauto_file_coding_system_function,
+               val = call1 (Vset_auto_coding_function,
                             make_string (read_buf, nread));
                /* Rewind the file for the actual read done later.  */
                if (lseek (fd, 0, 0) < 0)
@@ -5180,15 +5195,16 @@ The function `find-file-name-handler' checks this list for a handler\n\
 for its argument.");
   Vfile_name_handler_alist = Qnil;
 
-  DEFVAR_LISP ("auto-file-coding-system-function",
-              &Vauto_file_coding_system_function,
+  DEFVAR_LISP ("set-auto-coding-function",
+              &Vset_auto_coding_function,
     "If non-nil, a function to call to decide a coding system of file.\n\
-One argument is passed to this function: the string of the first\n\
-few lines of a file to be read.\n\
+One argument is passed to this function: the string of concatination\n\
+or the heading 1K-byte and the tailing 3K-byte of a file to be read.\n\
 This function should return a coding system to decode the file contents\n\
 specified in the heading lines with the format:\n\
-       -*- ... coding: CODING-SYSTEM; ... -*-");
-  Vauto_file_coding_system_function = Qnil;
+       -*- ... coding: CODING-SYSTEM; ... -*-\n\
+or local variable spec of the tailing lines with `coding:' tag.");
+  Vset_auto_coding_function = Qnil;
 
   DEFVAR_LISP ("after-insert-file-functions", &Vafter_insert_file_functions,
     "A list of functions to be called at the end of `insert-file-contents'.\n\