[Cvs-cvs] ccvs/src ChangeLog rcs.c

[Derek Robert Price]

CVSROOT:        /cvsroot/cvs
Module name:    ccvs
Changes by:     Derek Robert Price <dprice>     06/09/07 19:45:06

Modified files:
        src            : ChangeLog rcs.c 

Log message:
        [bug #17560]
        * rcs.c (apply_rcs_changes): Improve comments.  Restore repaired error
        handling.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/ccvs/src/ChangeLog?cvsroot=cvs&r1=1.3494&r2=1.3495
http://cvs.savannah.gnu.org/viewcvs/ccvs/src/rcs.c?cvsroot=cvs&r1=1.380&r2=1.381

Patches:
Index: ChangeLog
===================================================================
RCS file: /cvsroot/cvs/ccvs/src/ChangeLog,v
retrieving revision 1.3494
retrieving revision 1.3495
diff -u -b -r1.3494 -r1.3495
--- ChangeLog   6 Sep 2006 22:10:15 -0000       1.3494
+++ ChangeLog   7 Sep 2006 19:45:06 -0000       1.3495
@@ -1,3 +1,9 @@
+2006-09-07  Derek Price  <address@hidden>
+
+       [bug #17560]
+       * rcs.c (apply_rcs_changes): Improve comments.  Restore repaired error
+       handling.
+
 2006-09-06  Larry Jones  <address@hidden>
 
        * rcs.c (apply_rcs_changes): Improve linked list handling.  Remove

Index: rcs.c
===================================================================
RCS file: /cvsroot/cvs/ccvs/src/rcs.c,v
retrieving revision 1.380
retrieving revision 1.381
diff -u -b -r1.380 -r1.381
--- rcs.c       6 Sep 2006 22:10:15 -0000       1.380
+++ rcs.c       7 Sep 2006 19:45:06 -0000       1.381
@@ -7398,10 +7398,10 @@
  * the VERS field of deleted lines is unchanged.
  *
  * RETURNS
- *   Non-zero if the change text is applied successfully to LINES.
+ *   Non-zero if the change text is applied successfully to ORIG_LINES.
  *
- *   If the change text does not appear to apply to LINES (e.g., a
- *   line number is invalid), this function will return zero and LINES
+ *   If the change text does not appear to apply to ORIG_LINES (e.g., a
+ *   line number is invalid), this function will return zero and ORIG_LINES
  *   will be in an undefined state (though refcounts and such will be
  *   preserved for garbage collection).
  *
@@ -7434,6 +7434,7 @@
     struct deltafrag *df;
     unsigned long numlines, lastmodline, offset;
     struct linevector lines;
+    int err;
 
     dfhead = NULL;
     dftail = &dfhead;
@@ -7515,16 +7516,24 @@
     /* offset created when adding/removing lines
        between new and original structure */
     offset = 0; 
-
+    err = 0;
     for (df = dfhead; df != NULL; )
     {
        unsigned int ln;
        unsigned long deltaend;
 
+       if (df->pos > orig_lines->nlines)
+           err = 1;
+
+       /* On error, just free the rest of the list.  */
+       if (!err)
+       {
        /* Here we need to get to the line where the next insert will
-          begin which is <df->pos> we will fill up to df->pos with
-          original items. */
-       for (deltaend = df->pos - offset; lastmodline < deltaend; lastmodline++)
+              begin, which is DF->pos in ORIG_LINES.  We will fill up to
+              DF->pos - OFFSET in LINES with original items.  */
+           for (deltaend = df->pos - offset;
+                lastmodline < deltaend;
+                lastmodline++)
        {
            /* we need to copy from the orig structure into new one */
            lines.vector[lastmodline] =
@@ -7593,31 +7602,41 @@
                /* we are removing this many lines from the source. */
                offset += df->nlines;
 
-               if (df->pos > orig_lines->nlines
-                   || df->pos + df->nlines > orig_lines->nlines)
-                   return 0;
-               if (delvers != NULL)
+                   if (df->pos + df->nlines > orig_lines->nlines)
+                       err = 1;
+                   else if (delvers)
                    for (ln = df->pos; ln < df->pos + df->nlines; ++ln)
-                   {
-                       if (--orig_lines->vector[ln]->refcount == 0)
-                           free (orig_lines->vector[ln]);
-                       else
+                           if (orig_lines->vector[ln]->refcount > 1)
+                               /* Annotate needs this but, since the original
+                                * vector is disposed of before returning from
+                                * this function, we only need keep track if
+                                * there are multiple references.
+                                */
                            orig_lines->vector[ln]->vers = delvers;
-                       orig_lines->vector[ln] = NULL;
-                   }
                break;
        }
+       }
 
        df = df->next;
        free (dfhead);
        dfhead = df;
     }
 
+    if (err)
+    {
+       /* No reason to try and move a half-mutated and known invalid
+        * text into the output buffer.
+        */
+       linevector_free (&lines);
+    }
+    else
+    {
     /* add the rest of the remaining lines to the data vector */
     for (; lastmodline < numlines; lastmodline++)
     {
        /* we need to copy from the orig structure into new one */
-       lines.vector[lastmodline] = orig_lines->vector[lastmodline + offset];
+           lines.vector[lastmodline] = orig_lines->vector[lastmodline
+                                                          + offset];
        lines.vector[lastmodline]->refcount++;
     }
 
@@ -7628,8 +7647,9 @@
     orig_lines->vector = lines.vector;
     orig_lines->lines_alloced = numlines;
     orig_lines->nlines = lines.nlines;
+    }
 
-    return 1;
+    return !err;
 }