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 <wk@gnupg.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/gpg-error.h.in b/src/gpg-error.h.in
index c0ac0eb..cb32c48 100644
--- a/src/gpg-error.h.in
+++ b/src/gpg-error.h.in
@@ -644,6 +644,11 @@ typedef struct _gpgrt_poll_s gpgrt_poll_t;
 typedef struct _gpgrt_poll_s es_poll_t;
 #endif
 
+/* The type of the string filter function as used by fprintf_sf et al.  */
+typedef char *(*gpgrt_string_filter_t) (const char *s, int n, void *opaque);
+
+
+
 gpgrt_stream_t gpgrt_fopen (const char *_GPGRT__RESTRICT path,
                             const char *_GPGRT__RESTRICT mode);
 gpgrt_stream_t gpgrt_mopen (void *_GPGRT__RESTRICT data,
@@ -783,6 +788,15 @@ int gpgrt_fprintf_unlocked (gpgrt_stream_t _GPGRT__RESTRICT stream,
                             const char *_GPGRT__RESTRICT format, ...)
                             GPGRT_ATTR_PRINTF(2,3);
 
+int gpgrt_fprintf_sf (gpgrt_stream_t _GPGRT__RESTRICT stream,
+                      gpgrt_string_filter_t sf, void *sfvalue,
+                      const char *_GPGRT__RESTRICT format,
+                      ...) GPGRT_ATTR_PRINTF(4,5);
+int gpgrt_fprintf_sf_unlocked (gpgrt_stream_t _GPGRT__RESTRICT stream,
+                               gpgrt_string_filter_t sf, void *sfvalue,
+                               const char *_GPGRT__RESTRICT format,
+                               ...) GPGRT_ATTR_PRINTF(4,5);
+
 int gpgrt_printf (const char *_GPGRT__RESTRICT format, ...)
                   GPGRT_ATTR_PRINTF(1,2);
 int gpgrt_printf_unlocked (const char *_GPGRT__RESTRICT format, ...)