From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.3 required=5.0 tests=BAYES_00, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,565ddc0e6b80e338 X-Google-Attributes: gid103376,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news2.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!wn14feed!worldnet.att.net!bgtnsc05-news.ops.worldnet.att.net.POSTED!53ab2750!not-for-mail Newsgroups: comp.lang.ada From: anon@anon.org (anon) Subject: Re: copying data between memory locations Reply-To: anon@anon.org (anon) References: <1188809968.217323.145640@r29g2000hsg.googlegroups.com> X-Newsreader: IBM NewsReader/2 2.0 Message-ID: Date: Wed, 05 Sep 2007 04:39:55 GMT NNTP-Posting-Host: 12.64.204.164 X-Complaints-To: abuse@worldnet.att.net X-Trace: bgtnsc05-news.ops.worldnet.att.net 1188967195 12.64.204.164 (Wed, 05 Sep 2007 04:39:55 GMT) NNTP-Posting-Date: Wed, 05 Sep 2007 04:39:55 GMT Organization: AT&T Worldnet Xref: g2news2.google.com comp.lang.ada:1744 Date: 2007-09-05T04:39:55+00:00 List-Id: ------------------------------------------- pragma Ada_83 ; -- limit GNAT to Ada 83. -- ------------------------------------------- with Interfaces ; with System ; procedure ytest is function Read_Memory ( Addr : System.Address ) return Interfaces.Unsigned_8 is begin -- Read_Memory declare Mem : Interfaces.Unsigned_8 ; for Mem'Address use Addr ; begin return Mem ; end ; end Read_Memory ; procedure Write_Memory ( Addr : System.Address ; Data : Interfaces.Unsigned_8 ) is begin -- Write_Memory declare Mem : Interfaces.Unsigned_8 ; for Mem'Address use Addr ; begin Mem := Data ; end ; end Write_Memory ; begin -- ytest null ; end ytest ; -- -- I think you can modify the code to fit your needs for records -- In <1188809968.217323.145640@r29g2000hsg.googlegroups.com>, jef.mangelschots@gmail.com writes: >In our current design, we have a package that maintains a list of >descriptors of various buffers in the application. We don't want to >know their datatypes or how to write data into them. We only want to >maintain a physical address of them and use that address to directly >write data into these buffers (this data comes out incoming packets >over the network). > >In C, this is very straightforward and use the address as a pointer >and simply copy the packet into the memory location. >I can't figure out a way to do this in Ada (at least not Ada83). > >suppose the following: > >type BUFFER_DETAILS_RECORD is >record > num_bytes : integer; > start_address : system.address; >end record; >type BUFFER_DETAILS_ARRAY_TYPE is array(1..2) of >BUFFER_DETAILS_RECORD; >BUFFER_DETAILS : constant BUFFER_DETAILS_ARRAY_TYPE := >BUFFER_DETAILS_ARRAY_TYPE'(1 => (num_bytes => 100, start_address => >16#123# ), 1 => (num_bytes => 200, start_address => 16#456# )); > >procedure insert_block(idx : in integer; num_bytes : in integer; >offset : in integer; data : BYTE_ARRAY_TYPE) is >begin > ??? how do I copy the content of data into the memory pointed to by >BUFFER_DETAILS(idx).start_address + offset >end; >