core: Add a base 64 decoder.

* src/b64dec.c: New. Taken from gnupg.  Prefix function names with
_gpgme_ and change to use standard C malloc functions.
* src/util.h.h (struct b64state): New.
* src/Makefile.am (main_sources): Add file.

--

The file b64dec.c has been taken from gnupg commit
e430ff6ad0b7dcfcebd92b825dd5168205447ff3

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

1 files changed, 20 insertions, 0 deletions

diff --git a/src/util.h b/src/util.h
index 9c62f57d..5a0f7906 100644
--- a/src/util.h
+++ b/src/util.h
@@ -147,6 +147,26 @@ gpgme_error_t _gpgme_map_gnupg_error (char *err);
 int _gpgme_map_pk_algo (int algo, gpgme_protocol_t protocol);
 
 
+/*-- b64dec.c --*/
+
+struct b64state
+{
+  int idx;
+  int quad_count;
+  char *title;
+  unsigned char radbuf[4];
+  int stop_seen:1;
+  int invalid_encoding:1;
+  gpg_error_t lasterr;
+};
+
+gpg_error_t _gpgme_b64dec_start (struct b64state *state, const char *title);
+gpg_error_t _gpgme_b64dec_proc (struct b64state *state,
+                                void *buffer, size_t length, size_t *r_nbytes);
+gpg_error_t _gpgme_b64dec_finish (struct b64state *state);
+
+
+
 /* Retrieve the environment variable NAME and return a copy of it in a
    malloc()'ed buffer in *VALUE.  If the environment variable is not
    set, return NULL in *VALUE.  */