[sys] More system calls, more stability, kill bad processes

Makefile

@@ -14,7 +14,7 @@ ECHO = `which echo` -e
 MODULES = $(patsubst %.c,%.o,$(wildcard kernel/core/*.c))
 FILESYSTEMS = $(patsubst %.c,%.o,$(wildcard kernel/core/fs/*.c))
 VIDEODRIVERS = $(patsubst %.c,%.o,$(wildcard kernel/core/video/*.c))
-BINARIES = initrd/bin/hello initrd/bin/echo initrd/bin/yes initrd/bin/cat
+BINARIES = initrd/bin/hello initrd/bin/echo initrd/bin/yes initrd/bin/cat initrd/bin/sh
 UTILITIES = util/bin/readelf util/bin/typewriter
 EMU = qemu
 GENEXT = genext2fs

kernel/core/cmos.c

@@ -68,6 +68,23 @@ get_time(
 	*seconds = from_bcd(values[0]);
 }
 
+int
+gettimeofday(struct timeval * t, void *z) {
+	uint16_t values[128];
+	cmos_dump(values);
+
+	/* Math Time */
+	uint32_t time = (from_bcd(values[9]) - 70) * 31556926 +
+					from_bcd(values[8]) * 2629743 +
+					from_bcd(values[7]) * 87400 +
+					from_bcd(values[4]) * 3600 +
+					from_bcd(values[2]) * 60 +
+					from_bcd(values[0]);
+	t->tv_sec = time;
+	t->tv_usec = 0;
+	return 0;
+}
+
 /*
  * vim:tabstop=4
  * vim:noexpandtab

kernel/core/panic.c

@@ -12,7 +12,8 @@ void kernel_halt() {
 
 void halt_and_catch_fire(char * error_message, const char * file, int line, struct regs * regs) {
 	__asm__ __volatile__("cli");
-	settextcolor(14,4);
+	settextcolor(0,11);
+	kprintf("Process %d did a dumb.\n", getpid());
 	kprintf("PANIC! %s\n", error_message);
 	kprintf("File: %s\n", file);
 	kprintf("Line: %d\n", line);
@@ -26,7 +27,9 @@ void halt_and_catch_fire(char * error_message, const char * file, int line, stru
 		kprintf("User ESP:   0x%x\n",  regs->useresp);
 		kprintf("eip=0x%x\n",          regs->eip);
 	}
-	kernel_halt();
+	kprintf("Killing process...\n");
+	resettextcolor();
+	kexit(0);
 }
 
 void assert_failed(const char *file, uint32_t line, const char *desc) {

kernel/core/syscall.c

@@ -67,6 +67,20 @@ static int close(int fd) {
 	return 0;
 }
 
+static int execve(const char * filename, char *const argv[], char *const envp[]) {
+	int i = 0;
+	while (argv[i]) {
+		++i;
+	}
+	/* Discard envp */
+	exec((char *)filename, i, (char **)argv);
+	return -1;
+}
+
+static int sys_fork() {
+	return fork();
+}
+
 /*
  * System Call Internals
  */
@@ -78,9 +92,12 @@ static uintptr_t syscalls[] = {
 	(uintptr_t)&open,
 	(uintptr_t)&read,
 	(uintptr_t)&write,
-	(uintptr_t)&close
+	(uintptr_t)&close,
+	(uintptr_t)&gettimeofday,
+	(uintptr_t)&execve,
+	(uintptr_t)&sys_fork,
 };
-uint32_t num_syscalls = 6;
+uint32_t num_syscalls = 9;
 
 void
 syscalls_install() {

kernel/core/task.c

@@ -157,7 +157,7 @@ switch_task() {
 	__asm__ __volatile__ ("mov %%ebp, %0" : "=r" (ebp));
 	eip = read_eip();
 	if (eip == 0x10000) {
-
+		__asm__ __volatile__ ("sti");
 		return;
 	}
 	current_task->eip = eip;
@@ -190,7 +190,6 @@ void
 enter_user_mode() {
 	set_kernel_stack(current_task->stack + KERNEL_STACK_SIZE);
 	__asm__ __volatile__(
-			"cli\n"
 			"mov $0x23, %ax\n"
 			"mov %ax, %ds\n"
 			"mov %ax, %es\n"
@@ -214,7 +213,6 @@ void
 enter_user_jmp(uintptr_t location, int argc, char ** argv) {
 	set_kernel_stack(current_task->stack + KERNEL_STACK_SIZE);
 	__asm__ __volatile__(
-			"cli\n"
 			"mov $0x23, %%ax\n"
 			"mov %%ax, %%ds\n"
 			"mov %%ax, %%es\n"

kernel/core/video/bochs.c

@@ -315,7 +315,6 @@ void draw_cursor() {
 }
 
 void bochs_write(char c) {
-	__asm__ __volatile__ ("cli");
 	cell_redraw(csr_x, csr_y);
 	if (c == '\n') {
 		for (uint16_t i = csr_x; i < TERM_WIDTH; ++i) {
@@ -346,7 +345,6 @@ void bochs_write(char c) {
 		csr_y = TERM_HEIGHT - 1;
 	}
 	draw_cursor();
-	__asm__ __volatile__ ("sti");
 }
 
 

kernel/include/syscall.h

@@ -62,7 +62,7 @@ DECL_SYSCALL2(stat,   const char *, void *);
 
 /* Process Control */
 DECL_SYSCALL0(getpid);
-DECL_SYSCALL3(exec, char *, char **, char **);
+DECL_SYSCALL3(execve, char *, char **, char **);
 DECL_SYSCALL0(fork);
 DECL_SYSCALL2(kill, int, int);
 DECL_SYSCALL1(wait, int *);
@@ -70,6 +70,8 @@ DECL_SYSCALL1(wait, int *);
 /* Memory management */
 DECL_SYSCALL1(sbrk, int);
 
+DECL_SYSCALL2(gettimeofday, void *, void *);
+
 
 #endif
 /*

kernel/include/system.h

@@ -247,6 +247,14 @@ extern void parse_args(char * argv);
 extern void get_time(uint16_t * hours, uint16_t * minutes, uint16_t * seconds);
 extern void get_date(uint16_t * month, uint16_t * day);
 
+struct timeval {
+	uint32_t tv_sec;
+	uint32_t tv_usec;
+};
+
+extern int gettimeofday(struct timeval * t, void * z);
+
+
 /* CPU Detect by Brynet */
 extern int detect_cpu();
 

kernel/main.c

@@ -157,9 +157,7 @@ int main(struct multiboot *mboot, uint32_t mboot_mag, uintptr_t esp)
 
 	start_shell();
 
-	fork();
-
-	if (getpid() == 0) {
+	if (fork()) {
 		char * args[] = {
 			"/bin/yes",
 			"\033[1;32mA\033[0m"

loader/sh.c

@@ -0,0 +1,12 @@
+#include <syscall.h>
+
+int main(int argc, char ** argv) {
+	/* A Simple Shell */
+	int i = syscall_fork();
+	if (i == 0) {
+		syscall_print("Herpy derpy!\n");
+	} else {
+		syscall_print("Hello World!\n");
+	}
+	return 0;
+}

loader/syscall.c

@@ -6,3 +6,6 @@ DEFN_SYSCALL3(open,  2, const char *, int, int)
 DEFN_SYSCALL3(read,  3, int, char *, int)
 DEFN_SYSCALL3(write, 4, int, char *, int)
 DEFN_SYSCALL1(close, 5, int)
+DEFN_SYSCALL2(gettimeofday, 6, void *, void *)
+DEFN_SYSCALL3(execve, 7, char *, char **, char **)
+DEFN_SYSCALL0(fork, 8)