Make read-symbol-positions-list more accurate

* src/lread.c (read_integer): Unread even EOF character.
(read1): Likewise.  Properly record start position of symbol.

2 files changed, 17 insertions, 26 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 10f4186c31c..c06c98c5418 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,8 @@
 2011-07-17  Andreas Schwab  <schwab@linux-m68k.org>
 
+        * lread.c (read_integer): Unread even EOF character.
+        (read1): Likewise.  Properly record start position of symbol.
+
         * lread.c (read1): Read `#:' as empty uninterned symbol if no
         symbol character follows.
 
diff --git a/src/lread.c b/src/lread.c
index bb0edd898da..ef1b1a812d2 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -2327,8 +2327,7 @@ read_integer (Lisp_Object readcharfun, EMACS_INT radix)
           c = READCHAR;
         }
 
-      if (c >= 0)
-        UNREAD (c);
+      UNREAD (c);
       *p = '\0';
     }
 
@@ -2583,8 +2582,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
               nskip *= 10;
               nskip += c - '0';
             }
-          if (c >= 0)
-            UNREAD (c);
+          UNREAD (c);
 
           if (load_force_doc_strings
               && (EQ (readcharfun, Qget_file_char)
@@ -2663,12 +2661,11 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
           if (!(c > 040
                 && c != 0x8a0
                 && (c >= 0200
-                    || !(strchr ("\"';()[]#`,", c)))))
+                    || strchr ("\"';()[]#`,", c) == NULL)))
             {
               /* No symbol character follows, this is the empty
                  symbol.  */
-              if (c >= 0)
-                UNREAD (c);
+              UNREAD (c);
               return Fmake_symbol (build_string (""));
             }
           goto read_symbol;
@@ -2852,7 +2849,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
         next_char = READCHAR;
         ok = (next_char <= 040
               || (next_char < 0200
-                  && (strchr ("\"';()[]#?`,.", next_char))));
+                  && strchr ("\"';()[]#?`,.", next_char) != NULL));
         UNREAD (next_char);
         if (ok)
           return make_number (c);
@@ -2977,11 +2974,6 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
             /* Otherwise, READ_BUFFER contains only ASCII.  */
           }
 
-        /* We want readchar_count to be the number of characters, not
-           bytes.  Hence we adjust for multibyte characters in the
-           string.  ... But it doesn't seem to be necessary, because
-           READCHAR *does* read multibyte characters from buffers. */
-        /* readchar_count -= (p - read_buffer) - nchars; */
         if (read_pure)
           return make_pure_string (read_buffer, nchars, p - read_buffer,
                                    (force_multibyte
@@ -2998,7 +2990,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
 
         if (next_char <= 040
             || (next_char < 0200
-                && (strchr ("\"';([#?`,", next_char))))
+                && strchr ("\"';([#?`,", next_char) != NULL))
           {
             *pch = c;
             return Qnil;
@@ -3018,6 +3010,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
       {
         char *p = read_buffer;
         int quoted = 0;
+        int start_position = readchar_count - 1;
 
         {
           char *end = read_buffer + read_buffer_size;
@@ -3048,10 +3041,11 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
               else
                 *p++ = c;
               c = READCHAR;
-            } while (c > 040
-                     && c != 0x8a0 /* NBSP */
-                     && (c >= 0200
-                         || !(strchr ("\"';()[]#`,", c))));
+            }
+          while (c > 040
+                 && c != 0x8a0 /* NBSP */
+                 && (c >= 0200
+                     || strchr ("\"';()[]#`,", c) == NULL));
 
           if (p == end)
             {
@@ -3064,8 +3058,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
               end = read_buffer + read_buffer_size;
             }
           *p = 0;
-          if (c >= 0)
-            UNREAD (c);
+          UNREAD (c);
         }
 
         if (!quoted && !uninterned_symbol)
@@ -3093,12 +3086,7 @@ read1 (register Lisp_Object readcharfun, int *pch, int first_in_list)
           if (EQ (Vread_with_symbol_positions, Qt)
               || EQ (Vread_with_symbol_positions, readcharfun))
             Vread_symbol_positions_list =
-              /* Kind of a hack; this will probably fail if characters
-                 in the symbol name were escaped.  Not really a big
-                 deal, though.  */
-              Fcons (Fcons (result,
-                            make_number (readchar_count
-                                         - XFASTINT (Flength (Fsymbol_name (result))))),
+              Fcons (Fcons (result, make_number (start_position)),
                      Vread_symbol_positions_list);
           return result;
         }