[bindings] Enhancement: add an optional logging callback to demi_args_t

[kyleholohan]

This PR adds a callback function to demi_args_t. If specified by the caller, it will be invoked by flexi_logger for all logging calls, as oppose to printing to stdout.

[Copilot]

Pull Request Overview

This PR enhances the bindings by adding an optional logging callback to demi_args_t, allowing log messages to be routed to a caller-specified C callback rather than stdout.

• Updated the sizes macro in tests/c/sizes.c to account for the new logging callback field.
• Added demi_log_callback_t and updated demi_args_t in src/rust/runtime/types/mod.rs.
• Extended logging initialization in src/rust/runtime/logging.rs and demi_init in src/rust/demikernel/bindings.rs to support the new callback.
• Updated the C header in include/demi/types.h to include the new logging callback type and related enum values.

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/c/sizes.c	Updated DEMI_ARGS_SIZE macro, now adding the callback size twice.
src/rust/runtime/types/mod.rs	Added a new logging callback type and a field in demi_args_t.
src/rust/runtime/logging.rs	Implemented a new LogWriter that routes logs to the C callback.
src/rust/demikernel/bindings.rs	Modified demi_init to call custom_initialize when a callback is provided.
include/demi/types.h	Added enum and typedef for the logging callback.

[github-actions]

libos = catpowder
commit id = e5cea45

collapsed_stack	num_calls	cycles_per_call	nanoseconds_per_call	total_duration	percent_total_duration	total_duration_exclusive	percent_total_duration_exclusive
bgc::inetstack::poll;inetstack::layer4::poll_once	19484143	700	279	12478775747	46	12472771960	85
bgc::inetstack::poll	9742071	1618	644	14534823404	54	2056047657	14
ioc::network::libos::push	16256	2794	1138	49026013	0	49026013	0
bgc::inetstack::poll;inetstack::layer4::poll_once;inetstack::layer4::receive_batch	5310	2975	1162	6105546	0	6101794	0
bgc::inetstack::tcp::established::background;tcp::established::background::retransmitter	11086	421	167	5154576	0	5154576	0
ioc::network::libos::pop	9047	471	187	3551185	0	3551185	0
bgc::inetstack::tcp::established::background;tcp::established::background::acknowledger	11096	683	262	3173659	0	3173659	0
bgc::inetstack::tcp::established::background	11096	1832	714	12305022	0	3114080	0
ioc::network::libos::connect	42	40142	15957	1722898	0	1722898	0
ioc::network::libos::pushto	384	5365	2136	1703404	0	1703404	0
demikernel::sgaalloc	6503	202	79	1024954	0	1024954	0
bgc::inetstack::tcp::passiveopen::background	42	29625	11879	995533	0	995533	0
bgc::inetstack::tcp::established::background;tcp::established::background::sender	11042	930	357	862708	0	862708	0
demikernel::sgafree	8759	92	37	676103	0	676103	0
bgc::inetstack::poll;inetstack::layer4::poll_once;inetstack::layer4::receive_batch;udp::receive	286	271	107	73799	0	73799	0
ioc::network::libos::close	47	2911	1159	68022	0	68022	0
ioc::network::libos::accept	38	2476	996	56748	0	56748	0
bgc::inetstack::arp::background	8	3100	1238	17860	0	17860	0
bgc::inetstack::icmp::background	1	1942	772	2104	0	2104	0

[github-actions]

libos = catnip
commit id = e5cea45

collapsed_stack	num_calls	cycles_per_call	nanoseconds_per_call	total_duration	percent_total_duration	total_duration_exclusive	percent_total_duration_exclusive
bgc::inetstack::poll;inetstack::layer4::poll_once;catnip::runtime::receive	29180936	200	79	5603974109	19	5603974109	43
bgc::inetstack::poll;inetstack::layer4::poll_once	29180936	376	149	10360581305	36	4751568469	36
bgc::inetstack::poll	14590468	939	371	13058813147	45	2698231842	21
ioc::network::libos::push	16185	1086	436	17548078	0	15420800	0
bgc::inetstack::poll;inetstack::layer4::poll_once;inetstack::layer4::receive_batch	2489	3622	1417	5124129	0	5104702	0
bgc::inetstack::tcp::established::background;tcp::established::background::retransmitter	11087	333	132	4515118	0	4513950	0
bgc::inetstack::tcp::established::background;tcp::established::background::acknowledger	11100	460	188	2887560	0	2860002	0
ioc::network::libos::pop	9047	375	149	2747076	0	2747076	0
bgc::inetstack::tcp::established::background	11100	1223	490	10801765	0	2729448	0
ioc::network::libos::push;catnip::runtime::transmit	8777	305	123	2309616	0	2309616	0
ioc::network::libos::connect	42	32838	13269	1359267	0	1305346	0
demikernel::sgaalloc	6503	134	54	713120	0	713120	0
bgc::inetstack::tcp::established::background;tcp::established::background::sender	11045	313	121	669639	0	658860	0
demikernel::sgafree	8759	81	32	654233	0	654233	0
bgc::inetstack::tcp::passiveopen::background	42	25469	10130	609182	0	555856	0
ioc::network::libos::pushto	384	2117	856	592799	0	458791	0
ioc::network::libos::pushto;catnip::runtime::transmit	384	776	309	134008	0	134008	0
bgc::inetstack::tcp::established::background;tcp::established::background::acknowledger;catnip::runtime::transmit	36	1318	544	118713	0	118713	0
ioc::network::libos::close	49	2601	1036	58456	0	58456	0
ioc::network::libos::connect;catnip::runtime::transmit	42	5869	2332	53921	0	53921	0
bgc::inetstack::tcp::passiveopen::background;catnip::runtime::transmit	21	15640	6249	53325	0	53325	0
bgc::inetstack::poll;inetstack::layer4::poll_once;inetstack::layer4::receive_batch;udp::receive	224	244	95	50140	0	50140	0
ioc::network::libos::accept	37	2311	925	49570	0	49570	0
bgc::inetstack::arp::background	7	3546	1402	22680	0	22680	0
bgc::inetstack::poll;inetstack::layer4::poll_once;inetstack::layer4::receive_batch;catnip::runtime::transmit	36	721	289	17782	0	17782	0
bgc::inetstack::tcp::established::background;tcp::established::background::sender;catnip::runtime::transmit	21	601	239	10779	0	10779	0
bgc::inetstack::tcp::established::background;tcp::established::background::retransmitter;catnip::runtime::transmit	14	1747	679	5948	0	5948	0
bgc::inetstack::icmp::background	1	1692	670	1877	0	1877	0

[iyzhang]

This looks great. thanks for doing it.