core: Add a limited version of gpgrt_ftruncate.

* src/gpg-error.h.in (gpgrt_ftruncate, es_ftruncate): New.
* src/gpg-error.def.in, src/gpg-error.vers: Add gpgrt_ftruncate.
* src/visibility.c (gpgrt_ftruncate): new.
* src/gpgrt-int.h (COOKIE_IOCTL_TRUNCATE): New.
* src/estream.c (func_mem_ioctl): Support new internal IOCTL.
(_gpgrt_ftruncate): New.
--

Right now the ftruncate works only on memory streams.  Can easily be
added to other stream times.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/gpgrt-int.h b/src/gpgrt-int.h
index b5a4dd1..09aad11 100644
--- a/src/gpgrt-int.h
+++ b/src/gpgrt-int.h
@@ -208,12 +208,12 @@ void _gpgrt_internal_trace_end (void);
 
 /*
  * A private cookie function to implement an internal IOCTL service.
- * and ist IOCTL numbers.
  */
 typedef int (*cookie_ioctl_function_t) (void *cookie, int cmd,
 					void *ptr, size_t *len);
 #define COOKIE_IOCTL_SNATCH_BUFFER 1
 #define COOKIE_IOCTL_NONBLOCK      2
+#define COOKIE_IOCTL_TRUNCATE      3
 
 /* An internal variant of gpgrt_cookie_close_function_t with a slot
  * for the ioctl function.  */
@@ -366,6 +366,7 @@ int _gpgrt_fseeko (gpgrt_stream_t stream, gpgrt_off_t offset, int whence);
 long int _gpgrt_ftell (gpgrt_stream_t stream);
 gpgrt_off_t _gpgrt_ftello (gpgrt_stream_t stream);
 void _gpgrt_rewind (gpgrt_stream_t stream);
+int  _gpgrt_ftruncate (estream_t stream, gpgrt_off_t length);
 
 int _gpgrt_fgetc (gpgrt_stream_t stream);
 int _gpgrt_fputc (int c, gpgrt_stream_t stream);