From 9ae00e9e07beb3bca4d81e18dd5209e0d9234644 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Tue, 4 Mar 2008 02:22:36 +0000 Subject: [PATCH] Fix ftell bug after ungetc. * libc/stdio/ftell.c (_ftell_r): Don't flush ungetc buffer on ftell. * libc/stdio64/ftello64.c (_ftello64_r): Likewise. * libc/stdio/fflush.c (_fflush_r): Clear unget buffer when repositioning underlying fd offset. ------------------------------------------------------------------- --- newlib/ChangeLog | 9 +++++++++ newlib/libc/stdio/fflush.c | 2 ++ newlib/libc/stdio/ftell.c | 9 ++++++--- newlib/libc/stdio64/ftello64.c | 9 ++++++--- 4 files changed, 23 insertions(+), 6 deletions(-) diff --git a/newlib/ChangeLog b/newlib/ChangeLog index a1ed163de..2d4458bb8 100644 --- a/newlib/ChangeLog +++ b/newlib/ChangeLog @@ -1,3 +1,12 @@ +2008-03-03 Eric Blake + + Fix ftell bug after ungetc. + * libc/stdio/ftell.c (_ftell_r): Don't flush ungetc buffer on + ftell. + * libc/stdio64/ftello64.c (_ftello64_r): Likewise. + * libc/stdio/fflush.c (_fflush_r): Clear unget buffer when + repositioning underlying fd offset. + 2008-03-02 Jeff Johnston * libc/include/getopt.h (no_argument): Added for glibc compatibility. diff --git a/newlib/libc/stdio/fflush.c b/newlib/libc/stdio/fflush.c index 24bd6c10e..33e2e7b26 100644 --- a/newlib/libc/stdio/fflush.c +++ b/newlib/libc/stdio/fflush.c @@ -164,6 +164,8 @@ _DEFUN(_fflush_r, (ptr, fp), fp->_p = fp->_bf._base; if (fp->_flags & __SOFF) fp->_offset = curoff; + if (HASUB (fp)) + FREEUB (ptr, fp); } else { diff --git a/newlib/libc/stdio/ftell.c b/newlib/libc/stdio/ftell.c index 2aa10b2c7..816cafa76 100644 --- a/newlib/libc/stdio/ftell.c +++ b/newlib/libc/stdio/ftell.c @@ -118,9 +118,12 @@ _DEFUN(_ftell_r, (ptr, fp), return -1L; } - /* Find offset of underlying I/O object, then - adjust for buffered bytes. */ - _fflush_r (ptr, fp); /* may adjust seek offset on append stream */ + /* Find offset of underlying I/O object, then adjust for buffered + bytes. Flush a write stream, since the offset may be altered if + the stream is appending. Do not flush a read stream, since we + must not lose the ungetc buffer. */ + if (fp->_flags & __SWR) + _fflush_r (ptr, fp); if (fp->_flags & __SOFF) pos = fp->_offset; else diff --git a/newlib/libc/stdio64/ftello64.c b/newlib/libc/stdio64/ftello64.c index 2fdfb784e..51dcd2796 100644 --- a/newlib/libc/stdio64/ftello64.c +++ b/newlib/libc/stdio64/ftello64.c @@ -108,9 +108,12 @@ _DEFUN (_ftello64_r, (ptr, fp), return -1L; } - /* Find offset of underlying I/O object, then - adjust for buffered bytes. */ - _fflush_r (ptr, fp); /* may adjust seek offset on append stream */ + /* Find offset of underlying I/O object, then adjust for buffered + bytes. Flush a write stream, since the offset may be altered if + the stream is appending. Do not flush a read stream, since we + must not lose the ungetc buffer. */ + if (fp->_flags & __SWR) + _fflush_r (ptr, fp); if (fp->_flags & __SOFF) pos = fp->_offset; else