Cursor movement and testing revamp

Makefile

@@ -52,7 +52,7 @@ OBJ_NAMES := src/os/main.o src/os/test.o os_entry.o src/lib/video/VGA_text.o \
 	src/lib/device/serial.o src/lib/device/ps2.o src/lib/device/keyboard.o \
 	src/lib/container/ring_buffer.o \
 	src/lib/stdlib/stdio.o src/lib/stdlib/stdlib.o src/lib/stdlib/string.o \
-  src/lib/pit/pit.o
+	src/lib/pit/pit.o src/lib/device/key_handlers.o
 
 
 .PHONY: clean qemu test

src/lib/device/key_handlers.c

@@ -0,0 +1,116 @@
+#include "key_handlers.h"
+
+#include "video/VGA_text.h"
+
+void specialHandler(KeyPress out) {
+    if (!(out.modifiers & KEY_MOD_SHIFT)) {
+        switch (out.code) {
+        case Key_backspace:
+            if (getCursor()->highlight_offset) {
+                highlightDeletePrev(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                deletePrevChar();
+            break;
+        case Key_delete:
+            if (getCursor()->highlight_offset) {
+                highlightDeleteCurrent(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                deleteCurrentChar();
+            break;
+        case Key_left:
+            if (getCursor()->highlight_offset) {
+                cursorHighlightLeft(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                cursorLeft();
+            break;
+        case Key_down:
+            if (getCursor()->highlight_offset) {
+                cursorHighlightDown(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                cursorDown();
+            break;
+        case Key_up:
+            if (getCursor()->highlight_offset) {
+                cursorHighlightUp(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                cursorUp();
+            break;
+        case Key_right:
+            if (getCursor()->highlight_offset) {
+                cursorHighlightRight(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            } else
+                cursorRight();
+            break;
+        default:
+            break;
+        }
+    } else {
+        if (((out.code == Key_up || out.code == Key_left) &&
+             cursorIsAtStart()) ||
+            ((out.code == Key_down || out.code == Key_right) &&
+             cursorIsAtEnd()))
+            return;
+        if ((out.code == Key_up || out.code == Key_left ||
+             out.code == Key_down || out.code == Key_right) &&
+            !getCursor()->highlight_offset)
+            highlightCurrentChar();
+        switch (out.code) {
+        case Key_up:
+            for (int i = 0; i < VGA_WIDTH && !cursorIsAtStart(); i++) {
+                if (getCursor()->highlight_offset > 0) {
+                    highlightCurrentChar();
+                    cursorLeft();
+                } else {
+                    cursorLeft();
+                    highlightCurrentChar();
+                }
+                getCursor()->highlight_offset--;
+            }
+            break;
+        case Key_down:
+            for (int i = 0; i < VGA_WIDTH && !cursorIsAtEnd(); i++) {
+                if (getCursor()->highlight_offset < 0) {
+                    highlightCurrentChar();
+                    cursorRight();
+                } else {
+                    cursorRight();
+                    highlightCurrentChar();
+                }
+                getCursor()->highlight_offset++;
+            }
+            break;
+        case Key_left:
+            if (getCursor()->highlight_offset > 0) {
+                highlightCurrentChar();
+                cursorLeft();
+            } else {
+                cursorLeft();
+                highlightCurrentChar();
+            }
+            getCursor()->highlight_offset--;
+            break;
+        case Key_right:
+            if (getCursor()->highlight_offset < 0) {
+                highlightCurrentChar();
+                cursorRight();
+            } else {
+                cursorRight();
+                highlightCurrentChar();
+            }
+            getCursor()->highlight_offset++;
+            break;
+        default:
+            break;
+        }
+        if ((out.code == Key_up || out.code == Key_left ||
+             out.code == Key_down || out.code == Key_right) &&
+            !getCursor()->highlight_offset)
+            highlightCurrentChar();
+    }
+}

src/lib/device/key_handlers.h

@@ -0,0 +1,8 @@
+#ifndef KEY_HANDLERS_H
+#define KEY_HANDLERS_H
+
+#include "keyboard.h"
+
+void specialHandler(KeyPress out);
+
+#endif

src/lib/device/ps2.c

@@ -3,6 +3,7 @@
 #include "../../os/hard/idt.h"
 #include "../../os/hard/port_io.h"
 #include "container/ring_buffer.h"
+#include "key_handlers.h"
 
 #define PS2_BUF_SIZE 64
 #define PS2_TIMEOUT 100000
@@ -72,6 +73,29 @@ const struct PS2Device *getPortType(int portnum) {
 // temporary include for #7
 #include "video/VGA_text.h"
 
+void vgaEditor(struct PS2Buf_t out) {
+    switch (out.keyEvent.code) {
+    case Key_backspace:
+    case Key_delete:
+    case Key_left:
+    case Key_down:
+    case Key_up:
+    case Key_right:
+        specialHandler(out.keyEvent);
+        break;
+    default:
+        char buf[2] = " ";
+        buf[0] = keyPressToASCII(out.keyEvent);
+        if (buf[0] != 0) {
+            if (getCursor()->highlight_offset) {
+                highlightDeletePrev(getCursor()->highlight_offset);
+                getCursor()->highlight_offset = 0;
+            }
+            print(buf, white);
+        }
+    }
+}
+
 void ps2HandlerPort1(isr_registers_t *regs) {
     uint8_t b = inb(PS2_DATA);
 
@@ -86,9 +110,7 @@ void ps2HandlerPort1(isr_registers_t *regs) {
 
         // temporary to satisfy exactly what issue #7 says
         if (out.keyEvent.code != Key_none && out.keyEvent.event == KeyPressed) {
-            char buf[2] = " ";
-            buf[0] = keyPressToASCII(out.keyEvent);
-            print(buf, white);
+            vgaEditor(out);
         }
     }
 }

src/lib/device/ps2.h

@@ -69,6 +69,8 @@ struct PS2Buf_t {
 int ps2Init();
 const struct PS2Device *getPortType(int portnum);
 
+void vgaEditor(struct PS2Buf_t out);
+
 bool ps2Present(void);
 bool ps2Port1Present(void);
 bool ps2Port2Present(void);
@@ -84,4 +86,4 @@ struct PS2Buf_t popDev1(void);
 struct PS2Buf_t peekDev2(void);
 struct PS2Buf_t popDev2(void);
 
-#endif
+#endif

src/lib/stdlib/stdio.c

@@ -5,11 +5,12 @@
 
 #define MAX_SNPRINTF_STRING 100
 
-int snprintf(char *restrict buffer, size_t bufsz, char *format, ...);
-int vsnprintf(char *restrict buffer, size_t bufsz, char *format, va_list ap);
+int snprintf(char *restrict buffer, size_t bufsz, const char *format, ...);
+int vsnprintf(char *restrict buffer, size_t bufsz, const char *format,
+              va_list ap);
 
 // Inspired by chapter 7.3 of The C Programming Language
-int snprintf(char *restrict buffer, size_t bufsz, char *format, ...) {
+int snprintf(char *restrict buffer, size_t bufsz, const char *format, ...) {
     va_list ap;
     int retval;
     va_start(ap, format);
@@ -19,8 +20,9 @@ int snprintf(char *restrict buffer, size_t bufsz, char *format, ...) {
     return retval;
 }
 
-int vsnprintf(char *restrict buffer, size_t bufsz, char *format, va_list ap) {
-    char *p;
+int vsnprintf(char *restrict buffer, size_t bufsz, const char *format,
+              va_list ap) {
+    const char *p;
 
     // valid types
     unsigned char c; // printf("%c\n", 'c');
@@ -54,6 +56,7 @@ int vsnprintf(char *restrict buffer, size_t bufsz, char *format, va_list ap) {
                 if (len + n + 1 < bufsz) {
                     memcpy(buffer, s, len);
                     buffer += len;
+                    n += len - 1;
                 } else {
                     return n;
                 }
@@ -75,19 +78,22 @@ int vsnprintf(char *restrict buffer, size_t bufsz, char *format, va_list ap) {
             case 'i':
                 i = va_arg(ap, int);
                 int temp = i;
-                int bufSize = 0;
+                len = 0;
                 if (i < 0) {
-                    bufSize++;
+                    len++;
                     temp *= -1;
                 }
-                for (; temp >= 1; temp = temp / 10, bufSize++)
+                for (; temp >= 1; temp = temp / 10, len++)
                     ;
+                if (i == 0)
+                    len++;
 
                 // checks if there is space for the entire string
                 // plus the null-terminating byte
-                if (bufSize + n + 1 < bufsz) {
+                if (len + n + 1 < bufsz) {
                     itoa_s(i, buffer, MAX_SNPRINTF_STRING - n);
-                    buffer += bufSize;
+                    buffer += len;
+                    n += len - 1;
                 } else {
                     return n;
                 }

src/lib/stdlib/stdio.h

@@ -3,6 +3,7 @@
 #include <stdarg.h>
 #include <stddef.h>
 
-int snprintf(char *restrict buffer, size_t bufsz, char *format, ...);
+int snprintf(char *restrict buffer, size_t bufsz, const char *format, ...);
 
-int vsnprintf(char *restrict buffer, size_t bufsz, char *format, va_list ap);
+int vsnprintf(char *restrict buffer, size_t bufsz, const char *format,
+              va_list ap);