Make a lot of changes in shell and fix some bugs

Co-authored-by: Ezequiel Bellver <ebellver@itba.edu.ar>
Co-authored-by: Juan Barmasch <jbarmasch@itba.edu.ar>

Kernel/asm/interrupts.asm

@@ -30,6 +30,8 @@ GLOBAL loadProcess
 GLOBAL _initialize_stack_frame
 GLOBAL _switchContext
 
+EXTERN getFPUaddress, getSSEaddress
+
 SECTION .text
 
 %macro pushState 0
@@ -136,9 +138,44 @@ picSlaveMask:
     pop     rbp
     retn
 
+; getFPUaddress:
+; 	push rcx
+; 	mov ecx, [auxi]
+; 	mov ecx, 1
+; 	xor ecx, [auxi]
+; 	cmp ecx, 0
+; 	jne .getSecond
+; 	mov rax, bytesForFPU1
+; 	jmp .finish
+; .getSecond:
+; 	mov rax, bytesForFPU2
+; .finish:
+; 	mov dword [auxi], ecx
+; 	pop rcx
+; 	ret
+
+; getSSEaddress:
+; 	push rcx
+; 	mov ecx, [auxi]
+; 	cmp ecx, 0
+; 	jne .getSecond
+; 	mov rax, bytesForSSEAligned1
+; 	jmp .finish
+; .getSecond:
+; 	mov rax, bytesForSSEAligned2
+; .finish:
+; 	pop rcx
+; 	ret
+
 ;8254 Timer (Timer Tick)
 _irq00Handler:
 	pushState
+	; push rax
+	; call getFPUaddress
+	; fsave [rax]
+	; call getSSEaddress
+	; fxsave [rax]
+	; pop rax
 	; fsave [bytesForFPU]
 	; fxsave [bytesForSSEAligned]
 
@@ -156,9 +193,13 @@ _irq00Handler:
 
 	; fxrstor [bytesForSSEAligned]
 	; frstor [bytesForFPU]
+	; push rax
+	; call getFPUaddress
+	; frstor [rax]
+	; call getSSEaddress
+	; fxrstor [rax]
+	; pop rax
 	popState
-	; pop rsi ; argv
-	; pop rdi ; argc 6004d8
 	iretq
 
 ;Keyboard
@@ -236,16 +277,24 @@ _initialize_stack_frame:
 	push 0x0 ; ss
     push rsi ; sp
     push 0x202 ; rflags
-    push 0x08 ; cs -- offset de la GDT
+    push 0x08 ; cs
     push rdi ; IP
-	; push rdx ; argc
+
-	; push rcx ; argv
+	mov rsi, rcx
+	mov rdi, rdx 
 
     pushState
-	; mov rdi, rsp
+	; fsave [bytesForFPU]
-	; call newStack
+	; push rax
+	; mov dword [auxi], 1
+	; call getFPUaddress
+	; call getSSEaddress
+	; pop rax
+	; fxsave [bytesForSSEAligned]
+
+	; fsave [r8]
+	; fxsave [r9]
 
-	; mov rax, rsp
     mov rsp, r10
     ret
 
@@ -262,41 +311,19 @@ _systemCallsHandler:
 	popStateNoRax
 	iretq
 
-; switch Context (int 81h)
-;	_switchContext:
-;		pushState
-;		
-;		call changeWindow
-;		mov rdi, rsp
-;		call preserveStack
-;	
-;		mov rsp, rax
-;		popState
-;		pop rsi ; argv
-;		pop rdi ; argc
-;		iretq
-
-; _switchContext:
-; 	pushState
-	
-; 	mov rdi, rsp
-; 	call updateRSP
-
-; 	call nextProcess
-
-; 	mov rsp, rax
-; 	popState
-; 	pop rsi ; argv
-; 	pop rdi ; argc
-; 	iretq
-
 SECTION .data
 	align 16
 	bytesForSSEAligned times 512 db 0
+	; bytesForSSEAligned1 times 512 db 0
+	; bytesForSSEAligned2 times 512 db 0
+	; counter dd 1
 
 SECTION .bss
 	aux resq 1
 	bytesForSSE resb 512
 	bytesForFPU resb 108
+	; bytesForFPU1 resb 108
+	; bytesForFPU2 resb 108
 	insPointer resb 8
 	rspPointer resb 8
+	; auxi resb 4

Kernel/drivers/video.c

@@ -1,8 +1,8 @@
 #include <stdint.h>
 #include "video.h"
 
-static uint8_t * const video = (uint8_t*)0xB8000;
+static uint8_t * const video = (uint8_t*) 0xB8000;
-static uint8_t * currentVideo = (uint8_t*)0xB8000;
+static uint8_t * currentVideo = (uint8_t*) 0xB8000;
 static const int width = 80;
 static const int height = 25;
 static int currentX = 0;
@@ -11,39 +11,6 @@ static int currentY = 0;
 int limitX[2] = {0, 80};
 int limitY[2] = {0, 25};
 
-//	char windowVideo = 1;
-//	
-//	void changeWindow() {
-//		windowVideo = 1 - windowVideo;
-//		moveToWindowVideo(windowVideo);
-//	}
-//	
-//	void moveToWindowVideo(char window) {
-//		if (window == -1) {
-//			windowVideo = -1;
-//			limitX[0] = 0;
-//			limitX[1] = 80;
-//			limitY[0] = 0;
-//			limitY[1] = 25;
-//		}
-//		if (window == 1) {
-//			windowVideo = 1;
-//			limitX[0] = 40;
-//			limitX[1] = 80;
-//			limitY[0] = 0;
-//			limitY[1] = 25;
-//		}
-//		if (window == 0) {
-//			windowVideo = 0;
-//			limitX[0] = 0;
-//			limitX[1] = 40;
-//			limitY[0] = 0;
-//			limitY[1] = 25;
-//		}
-//		currentX = limitX[0];
-//		currentY = limitY[0];
-//	}
-
 void increment() {
 	currentX++;
 	if (currentX >= limitX[1]) {
@@ -89,7 +56,10 @@ int printStringLen(int color, const char * string, int maxLen) {
 
 		if (*string == '\n') {
 			new_line();
-			return i;
+			// return i;
+			string++;
+			i++;
+			continue;
 		}
 		else if (*string == '\b') {
 			backspace();
@@ -109,9 +79,7 @@ int printStringLen(int color, const char * string, int maxLen) {
 }
 
 void backspace() {
-	if (currentVideo > video) {
+	if (video + currentY * width * 2 + currentX * 2 > video) {
-		currentVideo -= 2;
-		*currentVideo = ' ';
 		currentX--;
 		if (currentX < limitX[0]) {
 			currentX = limitX[1];
@@ -119,6 +87,7 @@ void backspace() {
 				currentY--;
 		}
 	}
+	*(video + currentY * width * 2 + currentX * 2) = ' ';
 }
 
 void new_line() {

Kernel/include/lib.h

@@ -12,5 +12,6 @@ int abs(int value);
 char * itoa(int value, char * buffer, int base, int length);
 void strlen(const char *str, int *len);
 int strcpy(char * strDest, const char * strSrc);
+char addSpaces(char * str, char qty);
 
 #endif

Kernel/include/pipe.h

@@ -0,0 +1,18 @@
+#ifndef PIPE_H
+#define PIPE_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include "lib.h"
+#include "scheduler.h"
+#include "memManager.h"
+#include "pipeLib.h"
+
+#define MAX_SEM 100
+#define SEM_NAME "Pipes"
+
+int exists(pipe_t * pipe);
+node_t * searchPipe(node_t ** previous, int fd);
+
+#endif

Kernel/include/pipeLib.h

@@ -0,0 +1,26 @@
+#ifndef PIPELIB_H
+#define PIPELIB_H
+
+#include "semLib.h"
+
+#define MAX_NAME 100
+#define PIPE_MAX_SIZE 1024
+
+typedef struct pipe_t {
+    int fd;
+    char buffer[PIPE_MAX_SIZE];
+    int current;
+    char name[MAX_NAME];
+    sem_t * sem;
+} pipe_t;
+
+typedef struct node_t {
+    pipe_t * pipe;
+    struct node_t * next;
+} node_t;
+
+pipe_t * openPipe(char * name);
+void writePipe(int fd, char c);
+char readPipe(int fd);
+
+#endif

Kernel/include/scheduler.h

@@ -1,19 +1,18 @@
 #ifndef SCHEDULER_H
 #define SCHEDULER_H
 
-#include "queue.h"
-#include <stdint.h>
-#include <stddef.h>
-#include <stdlib.h>
 #include "memManager.h"
+#include <stdlib.h>
 #include "lib.h"
+#include <stddef.h>
+#include "schedulerLib.h"
 
 void forceTimer();
 void haltcpu();
 
 #define STACK_SIZE 1024 * 512
 #define MAX_PRIORITY 40 // Maximum number for a priority
-#define MIN_PRIORITY 0 // Minimum number for a priority (yet maximum level of priority) // me gusta
+#define MIN_PRIORITY 0 // Minimum number for a priority (yet maximum level of priority)
 #define DEF_PRIORITY 0
 #define PROCESS_DATA_MAX_SIZE 100
 #define MAX_ATTR_SIZE 6
@@ -21,20 +20,10 @@ void haltcpu();
 
 typedef struct processCDT * processADT;
 
-uint64_t nextProcess();
 void idle();
-void initScheduler();
-void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[]);
 void newProcess(processADT process, char * name, char priority, char foreground, uint64_t rsp, uint64_t rbp);
-char block(int pid);
+uint64_t nextProcess();
-char unblock(int pid);
-char kill(int pid);
-void exitProcess();
-char nice(char offset);
 void updateRSP(uint64_t newRsp);
-int getPid();
-char quitCPU();
 char getProcessData(char * out, processADT proc);
-char * processes();
 
 #endif

Kernel/include/schedulerLib.h

@@ -0,0 +1,19 @@
+#ifndef SCHEDULERLIB_H
+#define SCHEDULERLIB_H
+
+#include <stdint.h>
+
+void initScheduler();
+void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[]);
+char block(int pid);
+char unblock(int pid);
+char kill(int pid);
+void exitProcess();
+char nice(char offset);
+int getPid();
+char quitCPU();
+char * processes();
+int getFdOut();
+int getFdIn();
+
+#endif

Kernel/include/sem.h

@@ -0,0 +1,18 @@
+#ifndef SEM_H
+#define SEM_H
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include "lib.h"
+#include "scheduler.h"
+#include "memManager.h"
+#include "semLib.h"
+
+#define MAX_SEM 100
+#define SEM_DATA_MAX_SIZE 100
+
+void enter_region(uint32_t * lock);
+void leave_region(uint32_t * lock);
+
+#endif

Kernel/include/semLib.h

@@ -0,0 +1,23 @@
+#ifndef SEMLIB_H
+#define SEMLIB_H
+
+#define MAX_NAME 100
+
+typedef struct pid_t {
+    int pid;
+    struct pid_t * next;
+} pid_t;
+
+typedef struct sem_t {
+    unsigned int value;
+    char name[MAX_NAME];
+    pid_t * entering;
+    pid_t * last;
+} sem_t;
+
+sem_t * semOpen(char * name, unsigned int value);
+int semClose(sem_t * sem);
+int semWait(sem_t * sem);
+int semPost(sem_t * sem);
+
+#endif

Kernel/include/semaphore.h

@@ -1,9 +0,0 @@
-#ifndef SEM_H
-#define SEM_H
-
-sem_t * semOpen(char * name, unsigned int value);
-int semClose(sem_t * sem);
-int semWait(sem_t * sem);
-int semPost(sem_t * sem);
-
-#endif

Kernel/interruptions/systemCalls.c

@@ -3,7 +3,10 @@
 #include "keyboard.h"
 #include "time.h"
 #include "pcb.h"
+#include "pipeLib.h"
+#include "schedulerLib.h"
 
+#define STDIN 0
 #define STDOUT 1
 #define STDERR 2
 
@@ -16,8 +19,14 @@ uint64_t write(uint64_t fd, uint64_t buffer, uint64_t length) {
 
     if (fd == STDOUT)
         color = STDOUT_COLOR;
-    else if (fd == STDERR)
+    else {
-        color = STDERR_COLOR;
+        fd = getFdOut();
+        int i = 0;
+	    while (bufferAux[i] != '\0' && i++ <= length) {
+            writePipe(fd, bufferAux[i]);
+        }
+        return i;
+    }
 
     return printStringLen(color, bufferAux, (int) length);
 }
@@ -26,6 +35,8 @@ uint64_t read(uint64_t fd, uint64_t buffer, uint64_t length) {
     char * bufferAux = (char *) buffer;
     int readBytes = 0;
 
+
+    if (fd == STDIN) {
         while (length-- > 0) {
             *bufferAux = getKeyFromBuffer();
             if (*bufferAux == 0)
@@ -33,10 +44,15 @@ uint64_t read(uint64_t fd, uint64_t buffer, uint64_t length) {
             readBytes++;
             bufferAux++;
         }
+    }
+    else {
+        fd = getFdIn();
+        readBytes += strcpy(buffer, readPipe(fd));
+    }
 
 	return readBytes;
 }
 
-void createProcess(void (*fn)) {
+// void createProcess(void (*fn)) {
-    newProcess(fn);
+//     newProcess(fn);
-}
+// }

Kernel/lib.c

@@ -67,6 +67,14 @@ int abs(int value) {
     return value < 0 ? -value : value;
 }
 
+char addSpaces(char * str, char qty) {
+    char aux = qty;
+    while (qty-- > 0) {
+        *str++ = ' ';
+    }
+    return aux;
+}
+ 
 char * itoa(int value, char * buffer, int base, int length) {
    if (base < 2 || base > 32) {
         return buffer;

Kernel/utils/memManagerFRT4.c

@@ -25,7 +25,9 @@ typedef unsigned long UBaseType_t;
 #define configTOTAL_HEAP_SIZE                   1024 * 1024 * 100
 #define configAPPLICATION_ALLOCATED_HEAP        0
 #define portBYTE_ALIGNMENT 8
+// #define portBYTE_ALIGNMENT 16
 #define portBYTE_ALIGNMENT_MASK ( 0x0007 ) // 8
+// #define portBYTE_ALIGNMENT_MASK ( 0x000F ) // 16
 #define pdFALSE			( ( BaseType_t ) 0 )
 #define pdTRUE			( ( BaseType_t ) 1 )
 #define portPOINTER_SIZE_TYPE uint32_t
@@ -198,12 +200,12 @@ void *pvReturn = NULL;
 					else {
 
 							ncNewline();
-				ncPrint("MALLOC: ");
+				// ncPrint("MALLOC: ");
-				ncPrintDec(xFreeBytesRemaining);
+				// ncPrintDec(xFreeBytesRemaining);
-				ncPrint(" ");
+				// ncPrint(" ");
-				ncPrintDec(xWantedSize);
+				// ncPrintDec(xWantedSize);
-				ncPrint(" ");
+				// ncPrint(" ");
-				ncPrintDec(configADJUSTED_HEAP_SIZE);
+				// ncPrintDec(configADJUSTED_HEAP_SIZE);
 							ncNewline();
 					}
 		}

Kernel/utils/pipe.c

@@ -1,99 +1,65 @@
-#include <stdint.h>
+#include "pipe.h"
-#include <stddef.h>
-#include <stdlib.h>
-#include "lib.h"
-#include "scheduler.h"
-#include "memManager.h"
-#include "semaphore.h"
 
-#define MAX_SEM 100
+int fds = 2;
-#define MAX_NAME 100
-#define PIPE_MAX_SIZE 1024
-#define SEM_NAME "Pipes"
 
-typedef struct pipe_t {
+node_t * firstPipe;
-    char buffer[PIPE_MAX_SIZE];
-    int current;
-    char name[MAX_NAME];
-    sem_t * sem;
-} pipe_t;
-
-typedef struct node_t {
-    pipe_t * pipe;
-    struct node_t * next;
-} node_t;
-
-node_t * first;
-
-// char initPipes() {
-    // if ((sem = semOpen(SEM_NAME)) == NULL)
-    //     return EXIT_FAILURE;
-    // return EXIT_SUCCESS;
-// }
 
 pipe_t * openPipe(char * name) {
-    // semWait(sem);
-
     pipe_t * pipe = pvPortMalloc(sizeof(pipe_t));
     strcpy(pipe->name, name);
-    if ((pipe->sem = semOpen(SEM_NAME)) == NULL)
+    pipe->fd = fds++;
+    if ((pipe->sem = semOpen(SEM_NAME, 1)) == NULL)
         return NULL;
 
     return pipe;
-    // semPost(sem);
 }
 
-void writePipe(pipe_t * pipe, char c) {
+void writePipe(int fd, char c) {
-    if (!exists(pipe))
+    node_t * prev = NULL;
-        return;
+    node_t * node = searchPipe(&prev, fd);
 
-    semWait(pipe->sem);
+    semWait(node->pipe->sem);
 
-    pipe->buffer[pipe->current++ % PIPE_MAX_SIZE] = c;
+    node->pipe->buffer[node->pipe->current++ % PIPE_MAX_SIZE] = c;
 
-    semPost(pipe->sem);
+    semPost(node->pipe->sem);
 }
 
-char readPipe(pipe_t * pipe) {
+char readPipe(int fd) {
-    if (!exists(pipe))
+    node_t * prev = NULL;
-        return -1;
+    node_t * node = searchPipe(&prev, fd);
 
-    semWait(pipe->sem);
+    semWait(node->pipe->sem);
 
-    char c = pipe->buffer[pipe->current-- % PIPE_MAX_SIZE];
+    char c = node->pipe->buffer[node->pipe->current-- % PIPE_MAX_SIZE];
 
-    semPost(pipe->sem);
+    semPost(node->pipe->sem);
 
     return c;
 }
 
-void closePipe(pipe_t * pipe) {
+void closePipe(int fd) {
     node_t * prev = NULL;
-    node_t * del = search(&prev, pipe);
+    node_t * del = searchPipe(&prev, fd);
     if (del == NULL)
         return;
 
-    semWait(pipe->sem);
+    semWait(del->pipe->sem);
     if (prev != NULL)
         prev->next = del->next;
-    else first->next = del->next;
+    else firstPipe->next = del->next;
 
-    vPortFree(pipe);
+    vPortFree(del->pipe);
     vPortFree(del);
     
-    semPost(pipe->sem);
+    semPost(del->pipe->sem);
 }
 
-int exists(pipe_t * pipe) {
+node_t * searchPipe(node_t ** previous, int fd) {
-    node_t * prev = NULL;
+    node_t * curr = firstPipe;
-    return search(&prev, pipe) != NULL;
-}
-
-node_t * search(node_t ** previous, pipe_t * pipe) {
-    node_t * curr = first;
     * previous = NULL;
     while (curr != NULL) {
-        if (curr->pipe == pipe) {
+        if (curr->pipe->fd == fd) {
             break;
         }
         * previous = curr;
@@ -103,7 +69,7 @@ node_t * search(node_t ** previous, pipe_t * pipe) {
         * previous = NULL;
         return NULL;
     }
-    if (curr == first) {
+    if (curr == firstPipe) {
         * previous = NULL;
         return curr;
     }

Kernel/utils/scheduler.c

@@ -1,6 +1,7 @@
 #include "scheduler.h"
 #define IDLE_PID 1
 
+// void _initialize_stack_frame(void *, void *, int, char**, void **, void **);
 void _initialize_stack_frame(void *, void *, int, char**);
 
 enum states {READY = 0, BLOCKED};
@@ -17,6 +18,8 @@ typedef struct processCDT {
     char foreground;
     enum states state;
     int * fd;
+    void * sseBytes;
+    void * fpuBytes;
 } processCDT;
 
 processCDT * firstReady = NULL;
@@ -67,6 +70,7 @@ void initScheduler() {
 // }
 
 void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[]) {
+// void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[], int * fd[2]) {
     if (firstReady != NULL && firstReady->pid == IDLE_PID)
         block(IDLE_PID);
 
@@ -95,7 +99,10 @@ void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *
     process->executions = 0;
     process->foreground = foreground;
     process->state = READY;
+    // process->sseBytes = pvPortMalloc(64);
+    // process->fpuBytes = pvPortMalloc(14);
 
+    // _initialize_stack_frame(fn, rbp, argc, argv, &(process->fpuBytes), &(process->sseBytes));
     _initialize_stack_frame(fn, rbp, argc, argv);
 
     if (firstReady == NULL)
@@ -115,6 +122,14 @@ void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *
     return;
 }
 
+void * getSSEaddress() {
+    return currentProcess->sseBytes;
+}
+
+void * getFPUaddress() {
+    return currentProcess->fpuBytes;
+}
+
 void newProcess(processADT process, char * name, char priority, char foreground, uint64_t rsp, uint64_t rbp) {
     // char aux[MAX_NAME_SIZE];
     // int j;
@@ -139,7 +154,7 @@ void newProcess(processADT process, char * name, char priority, char foreground,
 //     exit();
 // }
 
-processADT search(processADT * previous, int pid, processADT first) {
+processADT searchProcess(processADT * previous, int pid, processADT first) {
     processADT curr = first;
     * previous = NULL;
     while (curr != NULL) {
@@ -162,7 +177,7 @@ processADT search(processADT * previous, int pid, processADT first) {
 
 char block(int pid) {
     processADT prev = NULL;
-    processADT del = search(&prev, pid, firstReady);
+    processADT del = searchProcess(&prev, pid, firstReady);
     if (del == NULL)
         return EXIT_FAILURE;
     else {
@@ -192,7 +207,7 @@ char block(int pid) {
 
 char unblock(int pid) {
     processADT prev = NULL;
-    processADT del = search(&prev, pid, firstBlocked);
+    processADT del = searchProcess(&prev, pid, firstBlocked);
     if (del == NULL)
         return EXIT_FAILURE;
     else {
@@ -213,9 +228,9 @@ char unblock(int pid) {
 
 char kill(int pid) {
     processADT prev = NULL;
-    processADT del = search(&prev, pid, firstReady);
+    processADT del = searchProcess(&prev, pid, firstReady);
     if (del == NULL) {
-        del = search(&prev, pid, firstBlocked);
+        del = searchProcess(&prev, pid, firstBlocked);
         if (del == NULL)
             return EXIT_FAILURE;
         else {
@@ -246,6 +261,18 @@ char kill(int pid) {
     return EXIT_SUCCESS;
 }
 
+int getFdOut() {
+    if (currentProcess == NULL)
+        return NULL;
+    return currentProcess->fd[1];
+}
+
+int getFdIn() {
+    if (currentProcess == NULL)
+        return NULL;
+    return currentProcess->fd[0];
+}
+
 void exitProcess() {
     kill(currentProcess->pid);
 }
@@ -280,14 +307,6 @@ char quitCPU() {
     return EXIT_SUCCESS;
 }
 
-char addSpaces(char * str, char qty) {
-    char aux = qty;
-    while (qty-- > 0) {
-        *str++ = ' ';
-    }
-    return aux;
-}
-
 char getGenProcessData(char ** out, char * written, char toAdd, char * in, char isLast) {
     char copied = strcpy(*out, in);
     *out += copied;

Kernel/utils/sem.c

@@ -1,37 +1,14 @@
-#include <stdint.h>
+#include "sem.h"
-#include <stddef.h>
-#include <stdlib.h>
-#include "lib.h"
-#include "scheduler.h"
-#include "memManager.h"
 
-#define MAX_SEM 100
-#define MAX_NAME 100
-#define SEM_DATA_MAX_SIZE 100
-
-void enter_region(uint32_t * lock);
-void leave_region(uint32_t * lock);
 static uint32_t semLock;
 
-typedef struct pid_t {
-    int pid;
-    struct pid_t * next;
-} pid_t;
-
-typedef struct sem_t {
-    unsigned int value;
-    char name[MAX_NAME];
-    pid_t * entering;
-    pid_t * last;
-} sem_t;
-
 typedef struct node_t {
     sem_t * sem;
     struct node_t * next;
 } node_t;
 
 static sem_t semaphores[MAX_SEM];
-node_t * first = NULL;
+node_t * firstSem = NULL;
 static char counter = 0;
 
 sem_t * semOpen(char * name, unsigned int value) {
@@ -40,8 +17,8 @@ sem_t * semOpen(char * name, unsigned int value) {
     sem_t * sem = pvPortMalloc(sizeof(sem_t));
     node_t * node = pvPortMalloc(sizeof(node_t));
     node->sem = sem;
-    node->next = first;    
+    node->next = firstSem;    
-    first = node;
+    firstSem = node;
     strcpy(sem->name, name);
     sem->value = value;
     counter++;
@@ -57,12 +34,12 @@ int semClose(sem_t * sem) {
 
     node_t * del = NULL;
 
-    if (first == sem) {
+    if (firstSem == sem) {
-        del = first;
+        del = firstSem;
-        first = first->next;
+        firstSem = firstSem->next;
     }
     else {
-        node_t * aux = first;
+        node_t * aux = firstSem;
         while (aux != NULL) {
             if (aux->next != NULL)
                 if (aux->next->sem == sem) {
@@ -176,7 +153,7 @@ char * getSems() {
     ans += strcpy(ans, info);
     // ans += 56;
 
-    node_t * aux = first;
+    node_t * aux = firstSem;
     while (aux != NULL) {
         char writtenChars = getSemaphoresData(ans, aux);
         if (writtenChars == EXIT_FAILURE)

Userland/SampleCodeModule/include/libc.h

@@ -8,7 +8,9 @@ void printString(char * string);
 void printStringError(char * string);
 void printStringLen(char * string, int len);
 void new_line();
+void backspace();
 char getChar();
+void putChar(char c);
 int abs();
 int atoi(char * buffer, int len);
 int strlen(const char * s);

Userland/SampleCodeModule/libc.c

@@ -30,13 +30,17 @@ int strcmp(const char * s1, const char * s2) {
 
 void putChar(char c){
     char buffer = c;
-    sys_write(1, &buffer, 1);
+    sys_write(1, &buffer, 0);
 }
 
 void new_line() {
     putChar('\n');
 }
 
+void backspace() {
+    putChar('\b');
+}
+
 void winClear() {
     sys_write(1, "\e\f", 2);
 }

Userland/SampleCodeModule/shell/commands/change.c

@@ -1,6 +0,0 @@
-#include "system.h"
-#include "change.h"
-
-void change() {
-    sys_switchContext();
-}

Userland/SampleCodeModule/shell/commands/clear.c

@@ -2,6 +2,6 @@
 #include "shell.h"
 #include "clear.h"
 
-void clear(char * window, int * offset) {
+void clear() {
-    clearWindow(window, offset);
+    winClear();
 }

Userland/SampleCodeModule/shell/commands/cpuid.c

@@ -1,5 +1,4 @@
 #include "cpu_id.h"
-#include "shell.h"
 
 int cpu_id(int *, int *, int *, int *);
 
@@ -101,12 +100,11 @@ static const int len = 16;
 int (* checks[])() = {check_cpuid, check_mmx, check_sse, check_sse2, check_sse3, check_sse41, check_sse42, check_aes, check_pclmulqdq, check_avx, check_vaesni, check_vpclmulqdq, check_f16c, check_fma, check_avx2, check_fpu};
 char * supports[] = {"cpuid_support", "mx_support", "sse_support", "sse2_support", "sse3_support", "sse41_support", "sse42_support", "aes_support", "pclmulqdq_support", "avx_support", "vaesni_support", "vpclmulqdq_support", "f16c_support", "fma_support", "avx2_support", "fpu_support"};
 
-void cpufeatures(char * window, int * offset) {
+void cpufeatures() {
     for (int i = 0; i < len; i++) {
         if (checks[i]()) {
-            addText(supports[i], window, offset);
+            printString(supports[i]);
-	        substractLine(window, offset);
+	        new_line();
         }
     }
-    printWindow(window);
 }

Userland/SampleCodeModule/shell/commands/help.c

@@ -1,13 +1,12 @@
 #include "libc.h"
 #include "shell.h"
 
-static char * info[] = {"change: Change the current working terminal (alternatively, press ALT+F1)", "clear: Clear the shell window", "cpufeatures: Show the features the cpu supports", "excdiv: Throw exception 0 (zero division)", "excop: Throw exception 6 (opcode error)", "help: Print information about commands", "inforeg: Print values of registers","printmem: Prints 32 bytes of memory, starting at a given direction", "quadratic: Receives 3 floats, quadratic coefficients, prints roots if real", "time: Prints date and time in UTC" };
+static char * info[] = {"clear: Clear the shell window", "cpufeatures: Show the features the cpu supports", "excdiv: Throw exception 0 (zero division)", "excop: Throw exception 6 (opcode error)", "help: Print information about commands", "inforeg: Print values of registers","printmem: Prints 32 bytes of memory, starting at a given direction", "quadratic: Receives 3 floats, quadratic coefficients, prints roots if real", "time: Prints date and time in UTC" };
-static const int len = 10;
+static const int len = 9;
 
-void help(char * window, int * offset) {
+void help() {
     for (int i = 0; i < len; i++) {
-        addText(info[i], window, offset);
+        printString(info[i]);
-        substractLine(window, offset);
+        new_line();
     }
-    printWindow(window);
 }

Userland/SampleCodeModule/shell/commands/inforeg.c

@@ -10,20 +10,19 @@ static char * regsNames[] = {
 	"R8: ", "R9: ", "R10: ", "R11: ", "R12: ", "R13: ", "R14: ", "R15: ",
 	"RSP: ", "RIP: "};
 
-void inforeg(char * window, int * offset) {
+void inforeg() {
 	uint64_t * regs = (uint64_t *) _getRegs();
 
 	char bufferAux[20];
 	
 	for (int i = 0; i < 17; i++) {
 		if (i % 5 == 0 && i != 0)
-			substractLine(window, offset);
+			new_line();
-		addText(regsNames[i], window, offset);
+		printString(regsNames[i]);
-		addText("0x", window, offset);
+		printStringLen("0x", 2);
-		addText(gtoa(regs[i], bufferAux, 16, 20), window, offset);
+		printString(gtoa(regs[i], bufferAux, 16, 20));
 		if (i != 14 && i % 5 != 4)
-			addText(" - ", window, offset);
+			printStringLen(" - ", 3);
 	}
-	printWindow(window);
+	new_line();
-	substractLine(window, offset);
 }

Userland/SampleCodeModule/shell/commands/printmem.c

@@ -13,16 +13,15 @@ void getMem(int * buffer, int initialAddress) {
     }
 }
 
-void printmem(char * window, int * offset, long dir) {
+void printmem(long dir) {
 	int buffer[8];
 	
 	getMem(buffer, dir);
 	
 	for (int i = 0; i < 8; i++) {
 		char bufferAux[8];
-		addText("0x", window, offset);
+		printStringLen("0x", 2);
-		addText(itoa(buffer[i], bufferAux, 16), window, offset);
+		printString(itoa(buffer[i], bufferAux, 16));
-		substractLine(window, offset);
+		new_line();
 	}
-	printWindow(window);
 }

Userland/SampleCodeModule/shell/commands/ps.c

@@ -1,10 +1,9 @@
 #include "libc.h"
 #include "shell.h"
 
-void ps(char * window, int * offset) {
+void ps() {
     char * output = sys_ps();
-    addText(output, window, offset);
+    printString(output);
-    printWindow(window);
+    new_line();
-    substractLine(window, offset);
+    // sys_free(output);
-    sys_free(output);
 }

Userland/SampleCodeModule/shell/commands/quadratic.c

@@ -2,41 +2,36 @@
 #include "quadratic.h"
 #include "shell.h"
 
-void quadratic(char * window, int * offset, double a, double b, double c) {
+void quadratic(double a, double b, double c) {
     double sol1, sol2;
     if (a == 0) {
-        addText("First argument cannot be 0", window, offset);
+        printStringLen("First argument cannot be 0\n", 28);
-        printWindow(window);
-        substractLine(window, offset);
         return;
     }
 
     int cond = quadSolver(a, b, c, &sol1, &sol2);
 
 	if (cond == 0) {
-		addText("Not real!", window, offset);
+		printStringLen("Not real!\n", 11);
-        printWindow(window);
-        substractLine(window, offset);
         return;
     }
 	
 	char buffer[30] = {0};
-	addText("Roots for ", window, offset);
+	printStringLen("Roots for ", 11);
     ftoa(a, buffer, 10);
-    addText(buffer, window, offset);
+    printString(buffer);
-    addText("x^2 + ", window, offset);
+    printStringLen("x^2 + ", 7);
     ftoa(b, buffer, 10);
-    addText(buffer, window, offset);
+    printString(buffer);
-    addText("x + ", window, offset);
+    printString("x + ");
     ftoa(c, buffer, 10);
-    addText(buffer, window, offset);
+    printString(buffer);
-    substractLine(window, offset);
+    new_line();
 	ftoa(sol1, buffer, 10);
-	addText(buffer, window, offset);
+	printString(buffer);
-	addText(" and ", window, offset);
+	printStringLen(" and ", 6);
     char buffer2[30] = {0};
 	ftoa(sol2, buffer2, 10);
-	addText(buffer2, window, offset);
+	printString(buffer2);
-    printWindow(window);
+    new_line();
-    substractLine(window, offset);
 }

Userland/SampleCodeModule/shell/commands/sem.c

@@ -1,10 +0,0 @@
-#include "libc.h"
-#include "shell.h"
-
-void sem(char * window, int * offset) {
-    char * output = sys_sem();
-    addText(output, window, offset);
-    printWindow(window);
-    substractLine(window, offset);
-    sys_free(output);
-}

Userland/SampleCodeModule/shell/commands/semCom.c

@@ -0,0 +1,9 @@
+#include "libc.h"
+#include "shell.h"
+
+void sem() {
+    char * output = sys_sem();
+    printString(output);
+    new_line();
+    // sys_free(output);
+}

Userland/SampleCodeModule/shell/commands/time.c

@@ -27,26 +27,24 @@ int getYear() {
     return sys_time(YEAR);
 }
 
-void printTime(int number, char * window, int * offset) {
+void printTime(int number) {
     char buffer[3] = {0};
     buffer[0] = number / 10 + '0';
     buffer[1] = number % 10 + '0';
     buffer[2] = '\0';
-    addText(buffer, window, offset);
+    printString(buffer);
 }
 
 void time(char * window, int * offset) {
-    printTime(getDay(), window, offset);
+    printTime(getDay());
-    addText("/", window, offset);
+    putChar('/');
-    printTime(getMonth(), window, offset);
+    printTime(getMonth());
-    addText("/", window, offset);
+    putChar('/');
-    printTime(getYear(), window, offset);
+    printTime(getYear());
-    addText(" ", window, offset);
+    putChar(' ');
-    printTime(getHours(), window, offset);
+    printTime(getHours());
-    addText(":", window, offset);
+    putChar(':');
-    printTime(getMinutes(), window, offset);
+    printTime(getMinutes());
-    addText(":", window, offset);
+    putChar(':');
-    printTime(getSeconds(), window, offset);
+    printTime(getSeconds());
-    printWindow(window);
-    substractLine(window, offset);
 }

Userland/SampleCodeModule/shell/include/change.h

@@ -1,6 +0,0 @@
-#ifndef CHANGE_H
-#define CHANGE_H
-
-void change();
-
-#endif

Userland/SampleCodeModule/shell/include/clear.h

@@ -1,6 +1,6 @@
 #ifndef CLEAR_LIB
 #define CLEAR_LIB
 
-void clear(char * window, int * offset);
+void clear();
 
 #endif

Userland/SampleCodeModule/shell/include/cpu_id.h

@@ -1,5 +1,8 @@
-#ifndef CPUID
+#ifndef CPUID_H
-#define CPUID
+#define CPUID_H
+
+#include "libc.h"
+#include "shell.h"
 
 // Tabla obtenidad de: https://wiki.osdev.org/CPUID
 enum {
@@ -68,7 +71,7 @@ enum {
 
 };
 
-void cpufeatures(char * window, int * offset);
+void cpufeatures();
 int cpu_id_support(void);
 
 #endif

Userland/SampleCodeModule/shell/include/help.h

@@ -1,6 +1,6 @@
 #ifndef HELP_LIB
 #define HELP_LIB
 
-void help(char * window, int * offset);
+void help();
 
 #endif

Userland/SampleCodeModule/shell/include/inforeg.h

@@ -1,6 +1,6 @@
 #ifndef REG_LIB
 #define REG_LIB
 
-void inforeg(char*, int*);
+void inforeg();
 
 #endif

Userland/SampleCodeModule/shell/include/printmem.h

@@ -1,6 +1,6 @@
 #ifndef MEM_LIB
 #define MEM_LIB
 
-void printmem(char* window, int* offset, long);
+void printmem(long);
 
 #endif

Userland/SampleCodeModule/shell/include/ps.h

@@ -1,6 +1,6 @@
 #ifndef PS_LIB
 #define PS_LIB
 
-void ps(char * window, int * offset);
+void ps();
 
 #endif

Userland/SampleCodeModule/shell/include/quadratic.h

@@ -2,6 +2,6 @@
 #define QUAD_LIB
 
 int quadSolver(double, double, double, double *, double *);
-void quadratic(char*, int*, double, double, double);
+void quadratic(double, double, double);
 
 #endif

Userland/SampleCodeModule/shell/include/sem.h

@@ -1,6 +0,0 @@
-#ifndef SEM_LIB
-#define SEM_LIB
-
-void sem(char * window, int * offset);
-
-#endif

Userland/SampleCodeModule/shell/include/semCom.h

@@ -0,0 +1,6 @@
+#ifndef SEM_LIB
+#define SEM_LIB
+
+void sem();
+
+#endif

Userland/SampleCodeModule/shell/include/shell.h

@@ -4,11 +4,7 @@
 #include "system.h"
 
 void shell(int argc, char *argv[]);
-void printWindow(char * window);
+void incorrect_comm(char * buffer);
-void addText(char * buffer, char * window, int * offset);
+void incorrect_arg(char * command);
-void incorrect_comm(char * buffer, char * window, int * offset);
-void incorrect_arg(char * command, char * window, int * offset);
-void clearWindow(char * window, int * offset);
-void substractLine(char * window, int * offset);
 
 #endif

Userland/SampleCodeModule/shell/include/time.h

@@ -7,7 +7,7 @@ int getHours();
 int getDays();
 int getMonths();
 int getYears();
-void time(char * window, int * offset);
+void time();
 
 #define SECONDS 0
 #define MINUTES 2

Userland/SampleCodeModule/shell/oldShell.c

@@ -0,0 +1,158 @@
+/*
+#include "libc.h"
+#include "help.h"
+#include "clear.h"
+#include "time.h"
+#include "shell.h"
+#include "inforeg.h"
+#include "printmem.h"
+#include "excDiv.h"
+#include "excOP.h"
+#include "quadratic.h"
+#include "cpu_id.h"
+#include "change.h"
+#include "ps.h"
+#include "semCom.h"
+
+#define SIZE 100
+#define MAX_ARGS 5
+
+#define COLS 80
+#define ROWS 25
+
+const int len = 9;
+char *commands_void[] = {"help", "time", "inforeg", "excdiv", "excop", "clear", "cpufeatures", "ps", "sem"};
+void (*func []) (char *, int *) = {help, time, inforeg, excdiv, excop, clear, cpufeatures, ps, semCom};
+
+void substractLine(char * window, int * offset) {
+    for (int i = 0; i < ROWS - 1; i++) {
+        for (int j = 0; j < COLS; j++) {
+            window[i * COLS + j] = window[(i + 1) * COLS + j];
+        }
+    }
+    for (int i = 0; i < COLS; i++) {
+        window[(ROWS - 1) * COLS + i - 1] = ' ';
+        window[ROWS * COLS] = 0;
+    }
+    *offset = (ROWS - 1) * COLS;
+}
+
+void addText(char * buffer, char * window, int * offset) {
+    while (*buffer != 0) {
+        if (*offset == ROWS * COLS - 1) substractLine(window, offset); 
+        if (*buffer == '\n') {
+            buffer++;
+            substractLine(window, offset);
+        }
+        window[(*offset)++] = *buffer++;
+    }
+}
+
+void printWindow(char * window) {
+    printStringLen(window, ROWS * COLS);
+}
+
+void scanfNoPrint(char * buffer, int maxSize, char * window, int * offset) {
+    char c;
+    int i = 0;
+    while ((c = getChar()) != '\n' && i < maxSize - 1) {
+        if (c != -1) {
+            // if (c == '\v')
+            //     sys_switchContext();
+            // else if (c == '\b' && i > 0) {
+            if (c == '\b' && i > 0) {
+                buffer[--i] = ' ';
+                window[--(*offset)] = ' ';
+                printWindow(window);
+            }
+            else if (c != 0 && c != '\b') { 
+                buffer[i++] = c;
+                if (*offset == ROWS * COLS - 1) substractLine(window, offset);
+                window[(*offset)++] = c;
+                printWindow(window);
+            }
+        }
+    }
+    buffer[i] = '\0';
+    if (*offset == ROWS * COLS - 1) substractLine(window, offset);
+    window[*offset] = ' ';
+}
+
+void clearWindow(char * window, int * offset) {
+    for (int i = 0; i <= ROWS * COLS; i++) {
+        window[i] = ' ';
+    }
+    window[ROWS * COLS] = 0;
+    *offset = (ROWS - 1) * COLS;
+    printWindow(window);
+}
+
+// static char window[ROWS * COLS + 1] = {[0 ... ROWS * COLS - 1] = ' ', 0};
+// static char buffer[SIZE] = {0};
+// static char *tokens[SIZE] = {0};
+void shell(int argc, char *argv[]) {
+    char window[ROWS * COLS + 1] = {[0 ... ROWS * COLS - 1] = ' ', 0};
+    int offset = (ROWS - 1) * COLS;
+
+    printWindow(window);
+    while (1) {
+        int comm_flag = 0;
+        addText("$> ", window, &offset);
+        printWindow(window);
+        char buffer[SIZE] = {0};
+        scanfNoPrint(buffer, SIZE, window, &offset);
+        substractLine(window, &offset);
+        char* tokens[SIZE] = {0};
+        tokens[0] = strstrip(buffer, ' ');
+        for (int i = 1; i < MAX_ARGS; i++) {
+            tokens[i] = strtok(tokens[i - 1], ' ');
+        }
+        for (int i = 0; i < len; i++) {
+            if (!strcmp(tokens[0], commands_void[i])) {
+                if (*tokens[1] != 0)
+                    incorrect_arg(tokens[0], window, &offset);
+                else
+                    (*func[i])(window, &offset);
+                comm_flag = 1;
+            }
+        }
+        if (!strcmp(tokens[0], "quadratic")) {
+            if (*tokens[4] != 0 || *tokens[3] == 0)
+                incorrect_arg(tokens[0], window, &offset);
+            else if (!isFloat(tokens[1]) || !isFloat(tokens[2]) || !isFloat(tokens[3]))
+                incorrect_arg(tokens[0], window, &offset);
+            else
+                quadratic(window, &offset, atof(tokens[1]), atof(tokens[2]), atof(tokens[3]));
+            comm_flag = 1;
+        }
+        if (!strcmp(tokens[0], "printmem")) {
+            if (*tokens[2] != 0 || *tokens[1] == 0)
+                incorrect_arg(tokens[0], window, &offset);
+            else {
+                int length = strlen(tokens[1]);
+                printmem(window, &offset, atoi(tokens[1], length));
+            }
+            comm_flag = 1;
+        }
+
+        if (!comm_flag) {
+            if (*tokens[0] != 0)
+                incorrect_comm(tokens[0], window, &offset);
+        }
+    }
+}
+
+void incorrect_comm(char * buffer, char* window, int * offset) {
+    addText(buffer, window, offset);
+    addText(" is not a BottlerShell command", window, offset);
+    printWindow(window);
+    substractLine(window, offset);
+}
+
+void incorrect_arg(char * command, char* window, int * offset) {
+    addText("Incorrect arguments for command ", window, offset);
+    addText(command, window, offset);
+    printWindow(window);
+    substractLine(window, offset);
+}
+*/

Userland/SampleCodeModule/shell/shell.c

@@ -1,17 +1,16 @@
 #include "libc.h"
 #include "help.h"
-#include "clear.h"
 #include "time.h"
 #include "shell.h"
+#include "clear.h"
 #include "inforeg.h"
 #include "printmem.h"
 #include "excDiv.h"
 #include "excOP.h"
 #include "quadratic.h"
 #include "cpu_id.h"
-#include "change.h"
 #include "ps.h"
-#include "sem.h"
+#include "semCom.h"
 
 #define SIZE 100
 #define MAX_ARGS 5
@@ -21,86 +20,33 @@
 
 const int len = 9;
 char *commands_void[] = {"help", "time", "inforeg", "excdiv", "excop", "clear", "cpufeatures", "ps", "sem"};
-void (*func []) (char *, int *) = {help, time, inforeg, excdiv, excop, clear, cpufeatures, ps, sem};
+void (*func []) () = {help, time, inforeg, excdiv, excop, clear, cpufeatures, ps, sem};
 
-void substractLine(char * window, int * offset) {
+void scanfNoPrint(char * buffer) {
-    for (int i = 0; i < ROWS - 1; i++) {
-        for (int j = 0; j < COLS; j++) {
-            window[i * COLS + j] = window[(i + 1) * COLS + j];
-        }
-    }
-    for (int i = 0; i < COLS; i++) {
-        window[(ROWS - 1) * COLS + i - 1] = ' ';
-        window[ROWS * COLS] = 0;
-    }
-    *offset = (ROWS - 1) * COLS;
-}
-
-void addText(char * buffer, char * window, int * offset) {
-    while (*buffer != 0) {
-        if (*offset == ROWS * COLS - 1) substractLine(window, offset); 
-        if (*buffer == '\n') {
-            buffer++;
-            substractLine(window, offset);
-        }
-        window[(*offset)++] = *buffer++;
-    }
-}
-
-void printWindow(char * window) {
-    printStringLen(window, ROWS * COLS);
-}
-
-void scanfNoPrint(char * buffer, int maxSize, char * window, int * offset) {
     char c;
     int i = 0;
-    while ((c = getChar()) != '\n' && i < maxSize - 1) {
+    while ((c = getChar()) != '\n' && i < SIZE - 1) {
         if (c != -1) {
-            // if (c == '\v')
-            //     sys_switchContext();
-            // else if (c == '\b' && i > 0) {
             if (c == '\b' && i > 0) {
                 buffer[--i] = ' ';
-                window[--(*offset)] = ' ';
+                backspace();
-                printWindow(window);
             }
             else if (c != 0 && c != '\b') { 
                 buffer[i++] = c;
-                if (*offset == ROWS * COLS - 1) substractLine(window, offset);
+                putChar(c);
-                window[(*offset)++] = c;
-                printWindow(window);
             }
         }
     }
     buffer[i] = '\0';
-    if (*offset == ROWS * COLS - 1) substractLine(window, offset);
-    window[*offset] = ' ';
 }
 
-void clearWindow(char * window, int * offset) {
-    for (int i = 0; i <= ROWS * COLS; i++) {
-        window[i] = ' ';
-    }
-    window[ROWS * COLS] = 0;
-    *offset = (ROWS - 1) * COLS;
-    printWindow(window);
-}
-
-// static char window[ROWS * COLS + 1] = {[0 ... ROWS * COLS - 1] = ' ', 0};
-// static char buffer[SIZE] = {0};
-// static char *tokens[SIZE] = {0};
 void shell(int argc, char *argv[]) {
-    char window[ROWS * COLS + 1] = {[0 ... ROWS * COLS - 1] = ' ', 0};
-    int offset = (ROWS - 1) * COLS;
-
-    printWindow(window);
     while (1) {
         int comm_flag = 0;
-        addText("$> ", window, &offset);
+        printStringLen("$> ", 3);
-        printWindow(window);
         char buffer[SIZE] = {0};
-        scanfNoPrint(buffer, SIZE, window, &offset);
+        scanfNoPrint(buffer);
-        substractLine(window, &offset);
+        new_line();
         char* tokens[SIZE] = {0};
         tokens[0] = strstrip(buffer, ' ');
         for (int i = 1; i < MAX_ARGS; i++) {
@@ -109,48 +55,45 @@ void shell(int argc, char *argv[]) {
         for (int i = 0; i < len; i++) {
             if (!strcmp(tokens[0], commands_void[i])) {
                 if (*tokens[1] != 0)
-                    incorrect_arg(tokens[0], window, &offset);
+                    incorrect_arg(tokens[0]);
                 else
-                    (*func[i])(window, &offset);
+                    (*func[i])();
                 comm_flag = 1;
             }
         }
         if (!strcmp(tokens[0], "quadratic")) {
             if (*tokens[4] != 0 || *tokens[3] == 0)
-                incorrect_arg(tokens[0], window, &offset);
+                incorrect_arg(tokens[0]);
             else if (!isFloat(tokens[1]) || !isFloat(tokens[2]) || !isFloat(tokens[3]))
-                incorrect_arg(tokens[0], window, &offset);
+                incorrect_arg(tokens[0]);
             else
-                quadratic(window, &offset, atof(tokens[1]), atof(tokens[2]), atof(tokens[3]));
+                quadratic(atof(tokens[1]), atof(tokens[2]), atof(tokens[3]));
             comm_flag = 1;
         }
         if (!strcmp(tokens[0], "printmem")) {
             if (*tokens[2] != 0 || *tokens[1] == 0)
-                incorrect_arg(tokens[0], window, &offset);
+                incorrect_arg(tokens[0]);
             else {
                 int length = strlen(tokens[1]);
-                printmem(window, &offset, atoi(tokens[1], length));
+                printmem(atoi(tokens[1], length));
             }
             comm_flag = 1;
         }
 
         if (!comm_flag) {
             if (*tokens[0] != 0)
-                incorrect_comm(tokens[0], window, &offset);
+                incorrect_comm(tokens[0]);
         }
     }
 }
 
-void incorrect_comm(char * buffer, char* window, int * offset) {
+void incorrect_comm(char * buffer) {
-    addText(buffer, window, offset);
+    printString(buffer);
-    addText(" is not a BottlerShell command", window, offset);
+    printStringLen(" is not a BottlerShell command\n", 32);
-    printWindow(window);
-    substractLine(window, offset);
 }
 
-void incorrect_arg(char * command, char* window, int * offset) {
+void incorrect_arg(char * command) {
-    addText("Incorrect arguments for command ", window, offset);
+    printStringLen("Incorrect arguments for command ", 33);
-    addText(command, window, offset);
+    printString(command);
-    printWindow(window);
+    new_line();
-    substractLine(window, offset);
 }