add asn_encode* and other encoders

doc/docsrc/asn_dec_rval.inc

@@ -5,7 +5,7 @@ may contain partially decoded data. This data may be useful for debugging
 Don't forget to discard the unused partially decoded data by calling
 \code{ASN_STRUCT_FREE()} or \code{ASN_STRUCT_RESET()}.
 
-The return value is returned in a compound structure:
+The function returns a compound structure:
 \begin{codesample}
 typedef struct {
     enum {
@@ -17,7 +17,7 @@ typedef struct {
 } asn_dec_rval_t;
 \end{codesample}
 
-The \code{.code} member specifies the decoding outcome.
+\noindent{}The \code{.code} member specifies the decoding outcome.
 
 \begin{tabular}[h!]{ll}
 \texttt{RC\_OK} & Decoded successfully and completely \\
@@ -25,6 +25,6 @@ The \code{.code} member specifies the decoding outcome.
 \texttt{RC\_FAIL} & Failed for good
 \end{tabular}
 
-The \code{.consumed} member specifies the amount of \code{buffer} data
+\noindent{}The \code{.consumed} member specifies the amount of \code{buffer} data
 that was used during parsing, irrespectively of the \code{.code}.
 

doc/docsrc/asn_enc_rval.inc

+
+The function returns a compound structure:
+
+\begin{codesample}
+typedef struct {
+    ssize_t encoded;
+    const asn_TYPE_descriptor_t *failed_type;
+    const void *structure_ptr;
+} asn_enc_rval_t;
+\end{codesample}
+
+\noindent{}In case of unsuccessful encoding, the \code{.encoded} member is set to -1 and
+the other members of the compound structure point to where the encoding has
+failed to proceed further.
+
+In case encoding is successful, the \code{.encoded} member specifies the
+size of the serialized output.