unix - Homebrew UNIX operating system

Age	Commit message (Collapse)	Author
2018-10-09	Added the f_inode element to struct file as a pointer to the file's	Jake Mannens
	inode in memory. Added a jump instruction in front of the multiboot header so that the kernel may be run as a binary image. The jump instruction will skip over the multiboot header to the beginning of the kernel's startup procedure in kboot. Moved the call to initialize the timer to earlier in the boot sequence. This is to allow for some drivers that may require it's functionality during the startup to function properly. Added functionality for the 'fast-gate' to the enable_a20 subroutine. Now, if the keyboard controller method fails when enabling the gate, an attempt is made to enable the A20 gate using the PS/2's fast-gate interface. If this also fails, the kernel will panic. Implemented TTY output for the console. The console is now TTY device 0 (the default for new userspace programs).
2018-07-25	Added missing prototype for puts() in stdio.h.	Jake Mannens
	Implemented a basic serial interface using COM0 which can be accessed with the system call sys_puts as well as the library functions rsputs() and rsprintf(). Renamed puts() in con.c to con_puts() and made the function static to avoid interference with the library function puts().
2018-07-08	Added a printf() function to the library under stdio.c which uses the	Jake Mannens
	vsprintf() function to render formatted strings and then the puts system call to output them. Moved the vsprintf() function from the kernel to the library. Furthermore, the prototype for the function has been moved from the kernel's headers, to the new header file stdio.h. Renamed the kernel's internal printf() function to printk() in order to avoid confusion with the library provided function. Renamed the sys_print system call to the more appropriate name, sys_puts. Added a new system call sys_time, which returns the system's uptime in seconds. This is mainly for testing the userspace binary and will not be permanent. Added the file time.c to the library which contains the caller for sys_time and a helper routine sleep() which delays execution for the specified number of seconds. The new header file time.h contains prototypes for both these functions as well as the definition for the type time_t. Fixed a bug in which the value of EAX was not properly passed to the system call handler, resulting in the wrong system call being executed. This was caused by the code in the SAVE macro not properly preserving the value. Fixed a bug in which the value of EAX was not preserved during a return from system call, but rather restored with the original EAX value prior to the call. As a result, system call return codes were not properly passed. This has been corrected by introducing a new macro RESTORE_SYS which carries out the same restore operations, but maintains EAX prior to the return.
2018-06-19	Added foundation code to initialize the PIT and create a 10ms jiffies	Jake Mannens
	counter.
2018-06-17	Cleaned up console I/O functions in con.c and con.h respectively.	Jake Mannens

2018-06-16	Initial commit	Jake Mannens