Update.

2004-05-13  Jakub Jelinek  <jakub@redhat.com>

	* libio/genops.c (_IO_default_xsputn): Avoid one overflow per char if
	count is negative, yet write_ptr < write_end.
	(_IO_default_xsgetn): Avoid one underflow per char if count is
	negative, yet read_ptr < read_end.

diff --git a/ChangeLog b/ChangeLog
index 6dcada2..5889b21 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2004-05-13  Jakub Jelinek  <jakub@redhat.com>
+
+       * libio/genops.c (_IO_default_xsputn): Avoid one overflow per char if
+       count is negative, yet write_ptr < write_end.
+       (_IO_default_xsgetn): Avoid one underflow per char if count is
+       negative, yet read_ptr < read_end.
+
 2004-05-12  Steven Munroe  <sjmunroe@us.ibm.com>
 
        * sysdeps/unix/sysv/linux/powerpc/bits/termios.h (XTABS): Define XTABS

diff --git a/libio/genops.c b/libio/genops.c
index 5b65e76..f233f36 100644 (file)
--- a/libio/genops.c
+++ b/libio/genops.c
@@ -447,10 +447,10 @@ _IO_default_xsputn (f, data, n)
   for (;;)
     {
       /* Space available. */
-      _IO_ssize_t count = f->_IO_write_end - f->_IO_write_ptr;
-      if (count > 0)
+      if (f->_IO_write_ptr < f->_IO_write_end)
        {
-         if ((_IO_size_t) count > more)
+         _IO_size_t count = f->_IO_write_end - f->_IO_write_ptr;
+         if (count > more)
            count = more;
          if (count > 20)
            {
@@ -462,9 +462,7 @@ _IO_default_xsputn (f, data, n)
 #endif
              s += count;
             }
-         else if (count <= 0)
-           count = 0;
-         else
+         else if (count)
            {
              char *p = f->_IO_write_ptr;
              _IO_ssize_t i;
@@ -504,10 +502,10 @@ _IO_default_xsgetn (fp, data, n)
   for (;;)
     {
       /* Data available. */
-      _IO_ssize_t count = fp->_IO_read_end - fp->_IO_read_ptr;
-      if (count > 0)
+      if (fp->_IO_read_ptr < fp->_IO_read_end)
        {
-         if ((_IO_size_t) count > more)
+         _IO_size_t count = fp->_IO_read_end - fp->_IO_read_ptr;
+         if (count > more)
            count = more;
          if (count > 20)
            {
@@ -519,9 +517,7 @@ _IO_default_xsgetn (fp, data, n)
 #endif
              fp->_IO_read_ptr += count;
            }
-         else if (count <= 0)
-           count = 0;
-         else
+         else if (count)
            {
              char *p = fp->_IO_read_ptr;
              int i = (int) count;