getlens.f

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C> @file
C> @brief Read the section lengths of a BUFR message.
C>
C> @author J. Ator @date 2005-11-29
 
C> This subroutine reads the lengths of all of the individual
C> sections of a given BUFR message, up to a specified point in
C> the message.
C>
C> This subroutine will work on any BUFR message encoded using
C> BUFR edition 2, 3, or 4
C>
C> @param[in]  MBAY -- integer(*): BUFR message
C> @param[in]   LL  -- integer: Number of last section for
C>                     which the length is to be read.
C>                     In other words, setting LL = N means to
C>                     read and return the lengths of Sections 0
C>                     through N (i.e. LEN0, LEN1,...,LENN).
C>                     Any section lengths that are not specified
C>                     to be read are returned with a default
C>                     placeholder value of -1.
C> @param[out]  LEN0 -- integer: Length (in bytes) of Section 0
C> @param[out]  LEN1 -- integer: Length (in bytes) of Section 1
C> @param[out]  LEN2 -- integer: Length (in bytes) of Section 2
C> @param[out]  LEN3 -- integer: Length (in bytes) of Section 3
C> @param[out]  LEN4 -- integer: Length (in bytes) of Section 4
C> @param[out]  LEN5 -- integer: Length (in bytes) of Section 5
C>
C> @remarks
C> - The start of the BUFR message (i.e. the string 'BUFR') must be
C>   aligned on the first 4 bytes of MBAY.
C>
C> @author J. Ator @date 2005-11-29
        RECURSIVE SUBROUTINE getlens
     .          (mbay,ll,len0,len1,len2,len3,len4,len5)
 
        USE modv_im8b
 
        dimension   mbay(*)
 
C-----------------------------------------------------------------------
C-----------------------------------------------------------------------
 
C       Check for I8 integers.
 
        IF(im8b) THEN
           im8b=.false.
 
           CALL x84(ll,my_ll,1)
           CALL getlens(mbay,my_ll,len0,len1,len2,len3,len4,len5)
           CALL x48(len0,len0,1)
           CALL x48(len1,len1,1)
           CALL x48(len2,len2,1)
           CALL x48(len3,len3,1)
           CALL x48(len4,len4,1)
           CALL x48(len5,len5,1)
 
           im8b=.true.
           RETURN
        ENDIF
 
        len0 = -1
        len1 = -1
        len2 = -1
        len3 = -1
        len4 = -1
        len5 = -1
 
        IF(ll.LT.0) RETURN
        len0 = iupbs01(mbay,'LEN0')
 
        IF(ll.LT.1) RETURN
        len1 = iupbs01(mbay,'LEN1')
 
        IF(ll.LT.2) RETURN
        iad2 = len0 + len1
        len2 = iupb(mbay,iad2+1,24) * iupbs01(mbay,'ISC2')
 
        IF(ll.LT.3) RETURN
        iad3 = iad2 + len2
        len3 = iupb(mbay,iad3+1,24)
 
        IF(ll.LT.4) RETURN
        iad4 = iad3 + len3
        len4 = iupb(mbay,iad4+1,24)
 
        IF(ll.LT.5) RETURN
        len5 = 4
 
        RETURN
        END