Correct documentation for MEID

[ric-plt/lib/rmr.git] / src / rmr / common / src / mbuf_api.c

diff --git a/src/rmr/common/src/mbuf_api.c b/src/rmr/common/src/mbuf_api.c
index e88ab23..84996ee 100644 (file)
--- a/src/rmr/common/src/mbuf_api.c
+++ b/src/rmr/common/src/mbuf_api.c
@@ -22,7 +22,9 @@
        Mnemonic:       mbuf_api.c
        Abstract:       These are common functions which work only on the mbuf and
                                thus (because they do not touch an endpoint or context)
-                               can be agnostic to the underlying transport.
+                               can be agnostic to the underlying transport, or the transport
+                               layer provides a transport specific function (e.g. payload 
+                               reallocation).
 
        Author:         E. Scott Daniels
        Date:           8 February 2019
@@ -51,6 +53,12 @@
                EINVAL id poitner, buf or buf header are bad.
                EOVERFLOW if the bytes given would have overrun
 
+       We have been told that the meid will be a string, so we enforce that even if
+       the user is copying in bytes.  We will add a 0 byte at len+1 when len is less
+       than the field size, or as the last byte (doing damage to their string) if
+       the caller didn't play by the rules. If they pass a non-nil terminated set
+       of bytes which are the field length, we'll indicate truncation.
+
 */
 extern int rmr_bytes2meid( rmr_mbuf_t* mbuf, unsigned char const* src, int len ) {
        uta_mhdr_t* hdr;
@@ -64,11 +72,20 @@ extern int rmr_bytes2meid( rmr_mbuf_t* mbuf, unsigned char const* src, int len )
        if( len > RMR_MAX_MEID ) {
                len = RMR_MAX_MEID;
                errno = EOVERFLOW;
-       }
+       } 
 
        hdr = (uta_mhdr_t *) mbuf->header;
        memcpy( hdr->meid, src, len );
 
+       if( len == RMR_MAX_MEID ) {
+               if( *(hdr->meid+len-1) != 0 ) {
+                       *(hdr->meid+len-1) = 0;
+                       errno = EOVERFLOW;
+               }
+       } else {
+               *(hdr->meid+len) = 0;
+       }
+
        return len;
 }
 
@@ -222,7 +239,7 @@ extern unsigned char*  rmr_get_xact( rmr_mbuf_t* mbuf, unsigned char* dest ) {
 }
 
 /*
-       Extracts the meid (managed equipment) from the header and copies the bytes
+       Extracts the meid (managed entity) from the header and copies the bytes
        to the user supplied area. If the user supplied pointer is nil, then
        a buffer will be allocated and it is the user's responsibilty to free.
        A pointer is returned to the destination memory (allocated or not)
@@ -447,3 +464,4 @@ extern unsigned char* rmr_get_srcip( rmr_mbuf_t* msg, unsigned char* dest ) {
 
        return rstr;
 }
+