Fix endless recursion on webui_malloc in debug mode.

[hdijkema]

Fix endless recursion on webui_malloc in debug mode.
We're sure the length of the debug message of _webui_malloc < 256,
so in that case we have enough room to print the debug message
without allocating memory with _webui_malloc, which prevents
an endless recursion to _webui_log.

[AlbertShown]

which prevents an endless recursion to _webui_log

Can you please show me where is that? because I can't find it.
if dynamic allocation failed then it will pass "Memory allocation failed for log" once only.

Another main reason is that char buf[256]; not thread-safe approach, especially when ui_event_blocking = false.

[hdijkema]

So, when _webui_malloc is called, _webui_malloc will log this:

Thus, the log handler gets called, which tries to allocate a buffer, which calls _webui_malloc, which debugs that it allocates memory, etc, etc, etc. So, this fix effectively prevents _webui_malloc from being called, and because _webui_malloc only needs some 50 bytes or so to write it's debug message, there won't be any recursion.

[AlbertShown]

I see, good catch. To fix this endless recursion and at the same time be thread-safe I suggest keeping dynamic allocation but using malloc() directly instead of _webui_malloc.

[hdijkema]

That is fine by me, although I think stack allocation of a character array may have some advantages over heap allocation.

• It's less costly (no heap allocation/deallocation).
• It's faster to access (not really a point in this use case).

And allocating on the stack is afaik thread safe.

By using a local array of decent size, the majority of debug cases there's probably no malloc/free needed

[AlbertShown]

And allocating on the stack is afaik thread safe.

Sorry I read the modification quick, and I taught the buffer was static but it's not.