core: New functions gpgrt_fprintf_sf anf gpgrt_fprintf_sf_unlocked.

* src/gpg-error.h.in (gpgrt_string_filter_t): New type.
(gpgrt_fprintf_sf, gpgrt_fprintf_sf_unlocked): New.
* src/gpg-error.vers, src/gpg-error.def.in: Add them.
* src/visibility.c (gpgrt_fprintf_sf): New.
(gpgrt_fprintf_sf_unlocked): New.
* src/estream-printf.c (pr_string): Add and use args sf, sfvalue and
string_no.
(do_format): Add args sf and sfvalue.  Keep a string format counter.
(_gpgrt_estream_format): Add args sf and sfvalue.  Change all callers
to provide NULL for them.
* src/estream.c (_gpgrt_vfprintf_unlocked, _gpgrt_vfprintf): Add sf
and sfvalue and adjust all callers.
(do_print_stream): Ditto.

* tests/t-printf.c (stream_to_string): New.
(struct sfstate_s): New.
(string_filter): New.
(check_fprintf_sf): New.
(main): Call new test.
--

The actual reason to implement these functions is to enhance the
internal logging function with a filter to sanitized strings so that
control values or other things can be quoted.

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

1 files changed, 8 insertions, 5 deletions

diff --git a/src/estream.c b/src/estream.c
index 72e93e0..3645dfe 100644
--- a/src/estream.c
+++ b/src/estream.c
@@ -2982,12 +2982,13 @@ print_writer (void *outfncarg, const char *buf, size_t buflen)
 /* The core of our printf function.  This is called in locked state. */
 static int
 do_print_stream (estream_t _GPGRT__RESTRICT stream,
+                 gpgrt_string_filter_t sf, void *sfvalue,
                  const char *_GPGRT__RESTRICT format, va_list ap)
 {
   int rc;
 
   stream->intern->print_ntotal = 0;
-  rc = _gpgrt_estream_format (print_writer, stream, format, ap);
+  rc = _gpgrt_estream_format (print_writer, stream, sf, sfvalue, format, ap);
   if (rc)
     return -1;
   return (int)stream->intern->print_ntotal;
@@ -4444,22 +4445,24 @@ _gpgrt_read_line (estream_t stream,
 
 int
 _gpgrt_vfprintf_unlocked (estream_t _GPGRT__RESTRICT stream,
+                          gpgrt_string_filter_t sf, void *sfvalue,
                           const char *_GPGRT__RESTRICT format,
                           va_list ap)
 {
-  return do_print_stream (stream, format, ap);
+  return do_print_stream (stream, sf, sfvalue, format, ap);
 }
 
 
 int
 _gpgrt_vfprintf (estream_t _GPGRT__RESTRICT stream,
+                 gpgrt_string_filter_t sf, void *sfvalue,
                  const char *_GPGRT__RESTRICT format,
                  va_list ap)
 {
   int ret;
 
   lock_stream (stream);
-  ret = do_print_stream (stream, format, ap);
+  ret = do_print_stream (stream, sf, sfvalue, format, ap);
   unlock_stream (stream);
 
   return ret;
@@ -4474,7 +4477,7 @@ _gpgrt_fprintf_unlocked (estream_t _GPGRT__RESTRICT stream,
 
   va_list ap;
   va_start (ap, format);
-  ret = do_print_stream (stream, format, ap);
+  ret = do_print_stream (stream, NULL, NULL, format, ap);
   va_end (ap);
 
   return ret;
@@ -4490,7 +4493,7 @@ _gpgrt_fprintf (estream_t _GPGRT__RESTRICT stream,
   va_list ap;
   va_start (ap, format);
   lock_stream (stream);
-  ret = do_print_stream (stream, format, ap);
+  ret = do_print_stream (stream, NULL, NULL, format, ap);
   unlock_stream (stream);
   va_end (ap);