c25ba1fccd
- PS/2 keyboard driver: IRQ1 handler, scancode set 1 translation, ring buffer, shift key support - SYS_READ (fd=0): non-blocking keyboard read for stdin - SYS_YIELD: calls schedule_tick directly (no nested INT 0x80) - SYS_EXEC: loads binary from CPIO initrd, replaces process image - User-space libc: crt0.S (C runtime startup), syscalls.h (inline syscall wrappers, basic string functions) - Shell app (sh): readline with echo/backspace, builtins (cd, env, help, exit), fork+exec for external commands - Updated build_apps.sh: C app support with crt0 linking, libc include path, .bss section in objcopy Tested: shell boots, keyboard input works, hello-world runs via fork+exec, env shows CWD, exit cleanly terminates.
22 lines
449 B
ArmAsm
22 lines
449 B
ArmAsm
/**
|
|
* @file crt0.S
|
|
* @brief C runtime startup for user-mode applications.
|
|
*
|
|
* Calls the C main() function and then exits with the return value.
|
|
*/
|
|
.section .text
|
|
.global _start
|
|
.extern main
|
|
|
|
_start:
|
|
/* Call main() */
|
|
call main
|
|
|
|
/* Exit with main's return value (in EAX) */
|
|
movl %eax, %ebx /* exit code = return value */
|
|
movl $0, %eax /* SYS_EXIT = 0 */
|
|
int $0x80
|
|
|
|
/* Should never reach here */
|
|
1: jmp 1b
|