msgpack-c with stack only

[wiesener]

Hi,

is there a version of msgpack which only uses stack and no heap? We need it for a embedded medical device where heap allocation is prohibited.

Thanks C.W.

[redboltz]

Unfortunately, msgpack-c requires heap allocation. msgpack-c uses new delete and malloc realloc free. If you want to avoid heap allocation with msgpack-c, write global new/delete operator to allocate from static pre-allocated array. In addition define your custom malloc realloc free to do the similar thing. That means writing custom allocator.

I guess that it doesn't match your case.

I don't know other MessagePack implementation that doen't use heap allocation.

[redboltz]

I sent the PR #791. It supports a minimal functionality to remove malloc. Could you try this?

https://github.com/redboltz/msgpack-c/blob/minimal_allocator_support/example/c/no_malloc_c.c

https://github.com/redboltz/msgpack-c/blob/minimal_allocator_support/example/cpp03/no_malloc.cpp

[redboltz]

my_malloc, my_realloc, and my_free in my example are toy level example implementation. Only for PoC. When you implement your custom allocator from static memory (or stack), you need to write more sophisticated implementation.

[redboltz]

Here are some memory allocator libraries:

• https://eli.thegreenplace.net/2008/10/17/memmgr-a-fixed-pool-memory-allocator
• https://github.com/eliben/code-for-blog/tree/master/2008/memmgr
• https://github.com/lynxlynx/smalloc