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/*
* The one ABI check that stands between this build and a silent hang.
*
* `hosted_osi_funcs_t` (host/esp_hosted_os_abstraction.h) is the function-pointer table ESP-Hosted
* reaches everything through - memory, sync, threads, GPIO, SDIO. src/net/port.zig defines it in
* Zig. Zig can assert its own layout; it cannot assert C's. This file asserts C's, so the two are
* checked against each other at build time.
*
* Why this is not paranoia. Four of the table's entries are guarded:
*
* #ifdef H_USE_MEMPOOL <- host/esp_hosted_os_abstraction.h:64-69
* void *(*_h_get_mempool)(...);
* ...
* #endif
*
* `#ifdef`, not `#if`. H_USE_MEMPOOL is defined by
* host/port/esp/freertos/include/port_esp_hosted_host_config.h:127-131 - to 1 or to 0, but always
* DEFINED. So the four pointers are present in any translation unit that saw that header, and
* absent in any that did not, and every entry after them shifts by four pointers.
*
* That is reachable, not theoretical: host/esp_hosted.h:14 and
* host/drivers/transport/transport_util.h:10 both include esp_hosted_os_abstraction.h as their
* FIRST include, so a TU reaching the struct through either of those - before any port header -
* gets the short layout. Under IDF's CMake the ordering happens to work out. Under our flags it
* would be luck.
*
* Measured with our exact flags, both ways:
*
* sizeof _h_config_gpio _h_event_post
* without the force-include 268 132 264
* with the force-include 284 148 280
*
* Sixteen bytes. A TU with the short layout calling _h_config_gpio jumps through a mempool
* pointer instead - which is a jump to the wrong function, on a board with no debugger, and the
* symptom would look exactly like the SDIO bus failing to come up.
*
* build.zig therefore force-includes port_esp_hosted_host_config.h into every ESP-Hosted
* translation unit, and compiles this file to assert that it worked. The numbers below are the
* long (correct) layout.
*/
#include "esp_hosted_os_abstraction.h"
#include <stddef.h>
/* The guard must be visible here, or this file is asserting the wrong layout and proving nothing. */
#ifndef H_USE_MEMPOOL
#error "H_USE_MEMPOOL is not visible: the force-include of port_esp_hosted_host_config.h is missing."
#endif
_Static_assert(
sizeof(hosted_osi_funcs_t) == 284,
"hosted_osi_funcs_t is not the 284-byte layout. Either the force-include of "
"port_esp_hosted_host_config.h was lost (short layout, 268), or ESP-Hosted changed the table. "
"Compare against the struct in src/net/port.zig before touching this number.");
/* Two offsets, chosen because they sit on either side of the mempool block: the first entry after
* it, and one near the end. If the block appears or disappears, both move. */
_Static_assert(
offsetof(hosted_osi_funcs_t, _h_config_gpio) == 148,
"_h_config_gpio moved. It is the first entry after the #ifdef H_USE_MEMPOOL block, so this is "
"what the short layout breaks first: 132 instead of 148.");
_Static_assert(
offsetof(hosted_osi_funcs_t, _h_event_post) == 280,
"_h_event_post moved. Together with the _h_config_gpio assertion this pins both ends of the "
"table.");
/* Field count, checked through the size. src/net/port.zig asserts its Zig struct has 71 fields;
* every entry is a pointer, so 71 * 4 must be the size on this 32-bit target. A size check alone
* would not catch a field deleted in one place and duplicated in another - the length survives and
* the two sides silently disagree about which pointer is which. */
_Static_assert(
sizeof(hosted_osi_funcs_t) == 71 * sizeof(void (*)(void)),
"hosted_osi_funcs_t is not 71 function pointers. Compare field by field against the struct in "
"src/net/port.zig - a count mismatch means one side has an entry the other does not, and every "
"entry after it calls the wrong function.");
const int esp_hosted_abi_assertions_hold = 1;
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