system - Panic, halt, and assertion helpers

Headers: kernel/include/kernel/system.h
Source: kernel/arch/i386/system.c

Low-level CPU control and unrecoverable-error reporting.

Macros

PANIC(msg)

#define PANIC(msg) panic(msg, __FILE__, __LINE__);

Convenience wrapper around panic() that automatically supplies the current source file and line number.

ASSERT(b)

#define ASSERT(b) ((b) ? (void)0 : panic_assert(__FILE__, __LINE__, #b));

Evaluates expression b. If b is false, calls panic_assert() with the file, line, and stringified expression. In non-debug builds the expression is still evaluated (no NDEBUG guard), so do not use it with side effects.

Functions

io_wait

void io_wait(void);

Inserts a tiny delay (approximately 400 ns) by executing two dummy jumps. Used when communicating with slow legacy hardware (e.g. ATA/ATAPI, 8259 PIC) where a brief pause is required between consecutive port writes.

halt

void halt(void);

Executes the HLT instruction, stopping the CPU until the next interrupt. Called after an unrecoverable exception or assertion failure to freeze execution. Typically invoked inside an infinite loop so the CPU never returns to the faulting code.

panic

void panic(char *msg, char *file, uint32_t line);

Handles an unrecoverable kernel error. Disables interrupts (CLI), prints a formatted message to the VGA terminal, then spins forever.

panic_assert

void panic_assert(char *file, uint32_t line, char *desc);

Like panic(), but formats the output as a failed assertion. Called automatically by the ASSERT() macro.