zephyr/boards/posix/native_posix/main.c

158 lines
4.1 KiB
C

/*
* Copyright (c) 2017 Oticon A/S
*
* SPDX-License-Identifier: Apache-2.0
*/
/*
* The basic principle of operation is:
* No asynchronous behavior, no indeterminism.
* If you run the same thing 20 times, you get exactly the same result 20
* times.
* It does not matter if you are running from console, or in a debugger
* and you go for lunch in the middle of the debug session.
*
* This is achieved as follows:
* The execution of native_posix is decoupled from the underlying host and its
* peripherals (unless set otherwise).
* In general, time in native_posix is simulated.
*
* But, native_posix can also be linked if desired to the underlying host,
* e.g.:You can use the provided Ethernet TAP driver, or a host BLE controller.
*
* In this case, the no-indeterminism principle is lost. Runs of native_posix
* will depend on the host load and the interactions with those real host
* peripherals.
*
*/
#include <stdio.h>
#include <soc.h>
#include "hw_models_top.h"
#include <stdlib.h>
#include <zephyr/sys/util.h>
#include <zephyr/sys/time_units.h>
#include "cmdline.h"
#include "irq_ctrl.h"
void posix_exit(int exit_code)
{
static int max_exit_code;
max_exit_code = MAX(exit_code, max_exit_code);
/*
* posix_soc_clean_up may not return if this is called from a SW thread,
* but instead it would get posix_exit() recalled again
* ASAP from the HW thread
*/
posix_soc_clean_up();
hwm_cleanup();
native_cleanup_cmd_line();
exit(max_exit_code);
}
/**
* Run all early native_posix initialization steps, including command
* line parsing and CPU start, until we are ready to let the HW models
* run via hwm_one_event()
*/
void posix_init(int argc, char *argv[])
{
/*
* Let's ensure that even if we are redirecting to a file, we get stdout
* and stderr line buffered (default for console)
* Note that glibc ignores size. But just in case we set a reasonable
* number in case somebody tries to compile against a different library
*/
setvbuf(stdout, NULL, _IOLBF, 512);
setvbuf(stderr, NULL, _IOLBF, 512);
run_native_tasks(_NATIVE_PRE_BOOT_1_LEVEL);
native_handle_cmd_line(argc, argv);
run_native_tasks(_NATIVE_PRE_BOOT_2_LEVEL);
hwm_init();
run_native_tasks(_NATIVE_PRE_BOOT_3_LEVEL);
posix_boot_cpu();
run_native_tasks(_NATIVE_FIRST_SLEEP_LEVEL);
}
/**
* Execute the simulator for at least the specified timeout, then
* return. Note that this does not affect event timing, so the "next
* event" may be significantly after the request if the hardware has
* not been configured to e.g. send an interrupt when expected.
*/
void posix_exec_for(uint64_t us)
{
uint64_t start = hwm_get_time();
do {
hwm_one_event();
} while (hwm_get_time() < (start + us));
}
#ifndef CONFIG_ARCH_POSIX_LIBFUZZER
/**
* This is the actual host process main routine. The Zephyr
* application's main() is renamed via preprocessor trickery to avoid
* collisions.
*
* Not used when building fuzz cases, as libfuzzer has its own main()
* and calls the "OS" through a per-case fuzz test entry point.
*/
int main(int argc, char *argv[])
{
posix_init(argc, argv);
while (true) {
hwm_one_event();
}
/* This line should be unreachable */
return 1; /* LCOV_EXCL_LINE */
}
#else /* CONFIG_ARCH_POSIX_LIBFUZZER */
const uint8_t *posix_fuzz_buf;
size_t posix_fuzz_sz;
/**
* Entry point for fuzzing (when enabled). Works by placing the data
* into two known symbols, triggering an app-visible interrupt, and
* then letting the OS run for a fixed amount of time (intended to be
* "long enough" to handle the event and reach a quiescent state
* again)
*/
int LLVMFuzzerTestOneInput(const uint8_t *data, size_t sz)
{
static bool posix_initialized;
if (!posix_initialized) {
posix_init(0, NULL);
posix_initialized = true;
}
/* Provide the fuzz data to Zephyr as an interrupt, with
* "DMA-like" data placed into posix_fuzz_buf/sz
*/
posix_fuzz_buf = data;
posix_fuzz_sz = sz;
hw_irq_ctrl_set_irq(CONFIG_ARCH_POSIX_FUZZ_IRQ);
/* Give the OS time to process whatever happened in that
* interrupt and reach an idle state.
*/
posix_exec_for(k_ticks_to_us_ceil64(CONFIG_ARCH_POSIX_FUZZ_TICKS));
return 0;
}
#endif