Added temporary Gets() Syscall

include/interrupt/syscall.h

@@ -3,9 +3,10 @@
 
 #include <interrupt/pit.h>
 #include <screen/text.h>
+#include <keyboard/keyboard.h>
 
 // System call count
-#define MAX_SYSCALLS 2
+#define MAX_SYSCALLS 3
 
 // Args: ebx - number of miliseconds
 void sys_sleep() {
@@ -19,7 +20,7 @@ void sys_sleep() {
 }
 
 // TODO: Use a Write() syscall and write to stdout
-// Args: ebx - string pointer
+// Args: ebx - char* string
 void sys_puts() {
     char* s;
     __asm__ volatile ("movl %%ebx, %0" : "=r"(s));
@@ -27,10 +28,18 @@ void sys_puts() {
     print(s);
 }
 
+// TODO: Use a Read() sycall and read from stdin
+// Returns: ebx - char* string
+void sys_gets() {
+    char* s = read();
+    __asm__ volatile ("movl %0, %%ebx" :: "r"(s));
+}
+
 // System call table
 void* syscalls[MAX_SYSCALLS] = {
     sys_sleep, 
     sys_puts, 
+    sys_gets, 
 };
 
 // int 0x80 - Syscall interrupt, handled by this function

include/keyboard/keyboard.h

@@ -18,7 +18,7 @@ typedef struct {
 keyboardState_t keyboard;
 
 __attribute__ ((interrupt))
-void keyboardHandler(intFrame_t* iframe) {
+void keyboardHandler(intFrame_t* iframe) { // TODO: Make this better and be able to read multi-byte scancode
     uint8_t scancode = inb(0x60);
     char c = US_Keyboard[keyboard.shift][scancode];
 
@@ -38,13 +38,13 @@ void keyboardHandler(intFrame_t* iframe) {
 
 char getc() {
     keyboard.character = '\0';
-    while (keyboard.character == '\0') __asm__ volatile ("hlt");
+    while (keyboard.character == '\0') { __asm__ volatile ("hlt"); }
     return keyboard.character;
 }
 
 // Reads until a newline
-char inputBuffer[MAX_INPUT_LENGTH];
 char* read() {
+    static char inputBuffer[MAX_INPUT_LENGTH];
     char c;
     uint8_t len = 0;
 
@@ -53,7 +53,7 @@ char* read() {
             if (len < 1) continue; // Can we backspace?
             len--;
             putc(c);
-        } else if (len + 1 != MAX_INPUT_LENGTH) { // Check if we can add a new character
+        } else if (len + 1 != MAX_INPUT_LENGTH) { // Check if we can add a new character (this method avoids overflow issues)
             inputBuffer[len++] = c;
             putc(c);
         }