[perl #41875] [PATCH] update io->fsize if lseek exceeds the file boundaries

[via RT]

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The patch makes PIO_unix_seek to update io->fsize value if lseek exceeds
the file boundaries.



Index: src/io/io_unix.c
===================================================================
--- src/io/io_unix.c	(Revision 17524)
+++ src/io/io_unix.c	(Arbeitskopie)
@@ -571,12 +571,25 @@
 PIO_unix_seek(Interp *interp, ParrotIOLayer *layer, ParrotIO *io,
               PIOOFF_T offset, INTVAL whence)
 {
-    PIOOFF_T pos;
+    PIOOFF_T pos, avail;
 
     UNUSED(interp);
     UNUSED(layer);
+    
+    if ((pos = lseek(io->fd, offset, whence)) >= 0) {
+        switch (whence) {
+            case SEEK_SET:
+              io->fsize = offset > io->fsize ? offset : io->fsize;
+              break;
+            case SEEK_CUR:
+              avail = io->b.next - io->b.startb + offset;
+              io->fsize = ( avail > io->fsize) ? avail : io->fsize;
+              break;
+            case SEEK_END:
+            default:
+              break;
+        }
 
-    if ((pos = lseek(io->fd, offset, whence)) >= 0) {
         io->lpos = io->fpos;
         io->fpos = pos;
     }