Re: Calling Ada from C (linux/gnat 4.3.2)

[anon@att.net]

Within C use normal external calling

extern <name> <arg list>


And in Ada use a specification file to declare routine.

 procedure <name> ( arg list ) ;
   pragma Export ( C, <name> ) ;

or you could use
   pragma Export ( C, <name>, "<linked name>" ) ;

In Ada the routine may or may not be in a package.


In <8ba649f0-7ca1-4f05-a158-74b074e401ee@o19g2000vbk.googlegroups.com>, awdorrin <awdorrin@gmail.com> writes:
>I am trying to port a program originally written on VxWork to Linux.
>The main program is written in C and spawns new threads and in the new
>threads calls are made to Ada procedures.
>
>In the original program, written with GreenHills AdaMulti, it appears
>that there was a call being made that I am assuming was initializing
>the Ada Runtime's task stack/control block (rts_init_task()) - however
>this is just a guess.
>
>In the version of the program I am migrating, I was seeing things that
>made me believe that the Ada thread's did not have their stacks setup
>properly, so I added the -fstack-check flag to the build.
>
>Now, the C program creates the new thread, which calls the ada
>procedure - and the moment the thread has an opportunity to run - the
>application exits with 'raised STORAGE_ERROR : stack overflow
>detected'
>
>I cannot get gdb to provide me a backtrace, since the program exits.
>If I try to break on the ada procedure name, I get a break, but trying
>to 'step' or 'next' keeps me in the main thread until a 'sleep' call
>lets the other thread run - at which point it raises the exception.
>
>I am assuming that the ada runtime is initializing and the
>STORAGE_ERROR is raised before it gets to execute any of the code in
>my Ada procedure.
>
>I have been trying to search to find what the proper way would be to
>call an Ada procedure from a C pthread, but have had zero luck. I also
>have been unable to determine what the equivalent of the
>'rts_init_task' would be with Gnat.
>
>Any have any ideas?