update sys/share/{dgn,lev}_lex.c

The HP C compiler for VMS issued a pair of diagnostics for both *_lex.c
files, about an expression of the form (unsigned_var <= 0) maybe not
being what was really intended, and it was right.  Changing that to
'< 1' would have suppressed the diagnostic but left the bug, which was
in code that performed a subtraction and then checked for a negative
result.  It worked in older flex versions when the variables were
signed, but got broken when they were changed to unsigned (no doubt in
respose to gcc complaining about comparing signed and unsigned in some
other spot where one of them was used).

The bug is in flex's original skeleton, so was inherited by our new
custom skeleton.  I've fixed it in the custom skeleton, which means
that sys/share/*_lex.c became out of date even though util/*_comp.l
remain unchanged.

diff --git a/sys/share/dgn_lex.c b/sys/share/dgn_lex.c
index 44ddfc5b31887cb7ea0e3d1d66e82a3d5f313588..6679b4d250a4a4c71279f63818da830beb46dec8 100644 (file)
--- a/sys/share/dgn_lex.c
+++ b/sys/share/dgn_lex.c
@@ -501,7 +501,7 @@ int yy_flex_debug = 0;
 #define YY_MORE_ADJ 0
 #define YY_RESTORE_YY_MORE_OFFSET
 char *yytext;
-/* NetHack 3.6  dgn_comp.l     $NHDT-Date: 1449385342 2015/12/06 07:02:22 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.16 $ */
+/* NetHack 3.6  dgn_comp.l     $NHDT-Date: 1449615114 2015/12/08 22:51:54 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.17 $ */
 /*     Copyright (c) 1989 by Jean-Christophe Collet */
 /*     Copyright (c) 1990 by M. Stephenson          */
 /* NetHack may be freely redistributed.  See license for details. */
@@ -1147,41 +1147,37 @@ static int yy_get_next_buffer ()
          */
         YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars) = 0;
     } else {
-        yy_size_t num_to_read =
-                YY_CURRENT_BUFFER_LVALUE->yy_buf_size - number_to_move - 1;
-
-        while (num_to_read <= 0) {
+        yy_size_t num_to_read;
+        /* just a shorter name for the current buffer */
+        YY_BUFFER_STATE b = YY_CURRENT_BUFFER_LVALUE;
+
+            /* [pr] This could probably be (b->yy_buf_size < number_to_move)
+             * since the allocated size is actually b->yy_buf_size + 2.
+             * The old code calculated num_to_read above (with same formula
+             * as is used below), then used (num_to_read <= 0) here, which
+             * got broken when num_to_read was changed to an unsigned type. */
+        while (b->yy_buf_size <= number_to_move + 1) {
             /* Not enough room in the buffer - grow it. */
 
-            /* just a shorter name for the current buffer */
-            YY_BUFFER_STATE b = YY_CURRENT_BUFFER_LVALUE;
             int yy_c_buf_p_offset = (int) ((yy_c_buf_p) - b->yy_ch_buf);
 
             if ( b->yy_is_our_buffer ) {
-                yy_size_t new_size = b->yy_buf_size * 2;
-
-                if ( new_size <= 0 )
-                    b->yy_buf_size += b->yy_buf_size / 8;
-                else
-                    b->yy_buf_size *= 2;
-
+                b->yy_buf_size += b->yy_buf_size / 4;
                 b->yy_ch_buf = (char *)
-                /* Include room in for 2 EOB chars. */
-                yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2 );
+                         /* Include room in for 2 EOB chars. */
+                         yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2 );
             } else
                 /* Can't grow it, we don't own it. */
                 b->yy_ch_buf = 0;
 
             if (! b->yy_ch_buf)
-                YY_FATAL_ERROR("fatal error - scanner input buffer overflow" );
+                YY_FATAL_ERROR("fatal error - scanner input buffer overflow");
 
             (yy_c_buf_p) = &b->yy_ch_buf[yy_c_buf_p_offset];
 
-            num_to_read = YY_CURRENT_BUFFER_LVALUE->yy_buf_size -
-                                number_to_move - 1;
-
         }
 
+        num_to_read = b->yy_buf_size - number_to_move - 1;
         if ( num_to_read > YY_READ_BUF_SIZE )
             num_to_read = YY_READ_BUF_SIZE;
 
@@ -1470,6 +1466,8 @@ YY_BUFFER_STATE yy_create_buffer (file,size )
        b = (YY_BUFFER_STATE) yyalloc(sizeof( struct yy_buffer_state )  );
        if ( ! b )
                YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );
+        if (!size)
+            size = YY_BUF_SIZE;
 
        b->yy_buf_size = (yy_size_t)size;
 

diff --git a/sys/share/lev_lex.c b/sys/share/lev_lex.c
index b34ae00915b56d3e3ef7eb7d187d87e8ef183d03..2920d2295868395a90fc4034092fe7c52eb23eeb 100644 (file)
--- a/sys/share/lev_lex.c
+++ b/sys/share/lev_lex.c
@@ -1022,7 +1022,7 @@ int yy_flex_debug = 0;
 #define YY_MORE_ADJ 0
 #define YY_RESTORE_YY_MORE_OFFSET
 char *yytext;
-/* NetHack 3.6  lev_comp.l     $NHDT-Date: 1449385344 2015/12/06 07:02:24 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.24 $ */
+/* NetHack 3.6  lev_comp.l     $NHDT-Date: 1449615116 2015/12/08 22:51:56 $  $NHDT-Branch: NetHack-3.6.0 $:$NHDT-Revision: 1.25 $ */
 /*     Copyright (c) 1989 by Jean-Christophe Collet */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -2390,41 +2390,37 @@ static int yy_get_next_buffer ()
          */
         YY_CURRENT_BUFFER_LVALUE->yy_n_chars = (yy_n_chars) = 0;
     } else {
-        yy_size_t num_to_read =
-                YY_CURRENT_BUFFER_LVALUE->yy_buf_size - number_to_move - 1;
-
-        while (num_to_read <= 0) {
+        yy_size_t num_to_read;
+        /* just a shorter name for the current buffer */
+        YY_BUFFER_STATE b = YY_CURRENT_BUFFER_LVALUE;
+
+            /* [pr] This could probably be (b->yy_buf_size < number_to_move)
+             * since the allocated size is actually b->yy_buf_size + 2.
+             * The old code calculated num_to_read above (with same formula
+             * as is used below), then used (num_to_read <= 0) here, which
+             * got broken when num_to_read was changed to an unsigned type. */
+        while (b->yy_buf_size <= number_to_move + 1) {
             /* Not enough room in the buffer - grow it. */
 
-            /* just a shorter name for the current buffer */
-            YY_BUFFER_STATE b = YY_CURRENT_BUFFER_LVALUE;
             int yy_c_buf_p_offset = (int) ((yy_c_buf_p) - b->yy_ch_buf);
 
             if ( b->yy_is_our_buffer ) {
-                yy_size_t new_size = b->yy_buf_size * 2;
-
-                if ( new_size <= 0 )
-                    b->yy_buf_size += b->yy_buf_size / 8;
-                else
-                    b->yy_buf_size *= 2;
-
+                b->yy_buf_size += b->yy_buf_size / 4;
                 b->yy_ch_buf = (char *)
-                /* Include room in for 2 EOB chars. */
-                yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2 );
+                         /* Include room in for 2 EOB chars. */
+                         yyrealloc((void *) b->yy_ch_buf,b->yy_buf_size + 2 );
             } else
                 /* Can't grow it, we don't own it. */
                 b->yy_ch_buf = 0;
 
             if (! b->yy_ch_buf)
-                YY_FATAL_ERROR("fatal error - scanner input buffer overflow" );
+                YY_FATAL_ERROR("fatal error - scanner input buffer overflow");
 
             (yy_c_buf_p) = &b->yy_ch_buf[yy_c_buf_p_offset];
 
-            num_to_read = YY_CURRENT_BUFFER_LVALUE->yy_buf_size -
-                                number_to_move - 1;
-
         }
 
+        num_to_read = b->yy_buf_size - number_to_move - 1;
         if ( num_to_read > YY_READ_BUF_SIZE )
             num_to_read = YY_READ_BUF_SIZE;
 
@@ -2713,6 +2709,8 @@ YY_BUFFER_STATE yy_create_buffer (file,size )
        b = (YY_BUFFER_STATE) yyalloc(sizeof( struct yy_buffer_state )  );
        if ( ! b )
                YY_FATAL_ERROR( "out of dynamic memory in yy_create_buffer()" );
+        if (!size)
+            size = YY_BUF_SIZE;
 
        b->yy_buf_size = (yy_size_t)size;