Add cat, filter and wc

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

Kernel/drivers/keyboard.c

@@ -212,7 +212,7 @@ static unsigned char kbdus_sh[250] =
     0,          /* 29   - Control */
   'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K', 'L', ':', /* 39 */
  '\'', '>',   0,        /* Left shift */
- '*', 'Z', 'X', 'C', 'V', 'B', 'N',            /* 49 */
+ '|', 'Z', 'X', 'C', 'V', 'B', 'N',            /* 49 */
   'M', ';', ':', '_',   0,              /* Right shift */
   '*',
     0,	/* Alt */

Kernel/drivers/video.c

@@ -13,23 +13,16 @@ int limitY[2] = {0, 25};
 
 void increment() {
 	currentX++;
-	if (currentX >= limitX[1]) {
+	if (currentX == limitX[1]) {
 		currentY++;
 		currentX = limitX[0];
-		if (currentY >= limitY[1]) 
+		if (currentY >= limitY[1]) {
-			currentY = limitY[0];
+			scroll();
+			currentY = limitY[1] - 1;
+		}
 	}
 }
 
-int atoi(char * string, int length) {
-    int res = 0, i = 0;
-    while (i < length) {
-        res = res * 10 + string[i++] - '0';
-    }
-    return res;
-}
-
-// "\e\f" para clear
 char checkIfEscapeSequence(const char * bufferAux) {
 	if (*bufferAux == '\e') {
 		bufferAux++;
@@ -42,21 +35,24 @@ char checkIfEscapeSequence(const char * bufferAux) {
 	return 0;
 }
 
+void scroll() {
+	for (int i = limitY[0]; i < limitY[1] - 1; i++) {
+		for (int j = limitX[0]; j < limitX[1]; j++) {
+			*(video + i * width * 2 + j * 2) = *(video + (i + 1) * width * 2 + j * 2);
+			*(video + i * width * 2 + j * 2 + 1) = *(video + (i + 1) * width * 2 + j * 2 + 1);
+		}
+	}
+	for (int j = limitX[0]; j < limitX[1]; j++) {
+		*(video + (limitY[1] - 1) * width * 2 + j * 2) = ' ';
+	}
+}
+
 int printStringLen(int color, const char * string, int maxLen) {
 	int i = 0;
 	
 	while (*string != '\0' && i <= maxLen) {
-		if (currentX >= limitX[1]) {
-			currentX = limitX[0];
-			currentY++;
-		}
-		if (currentY >= limitY[1]) {
-			currentY = limitY[0];
-		}
-
 		if (*string == '\n') {
 			new_line();
-			// return i;
 			string++;
 			i++;
 			continue;
@@ -93,15 +89,18 @@ void backspace() {
 void new_line() {
 	currentX = limitX[0];
 	currentY++;
-	if (currentY == limitY[1])
+	if (currentY == limitY[1]) {
-		currentY = limitY[0];
+		scroll();
+		currentY = limitY[1] - 1;
+	}
 }
 
 void clear() {
-	for (int i = limitX[0]; i < (limitX[1] - limitX[0]) * 2 * (limitY[1] - limitY[0]); i++) {	
-		printStringLen(15, " ", 1);
-	}
-
 	currentX = limitX[0];
 	currentY = limitY[0];
+	for (int i = limitY[0]; i < limitY[1]; i++) {
+		for (int j = limitX[0]; j < limitX[1]; j++) {
+			*(video + i * width * 2 + j * 2) = ' ';
+		}
+	}
 }

Kernel/include/pipeLib.h

@@ -7,7 +7,7 @@
 #define PIPE_MAX_SIZE 1024
 
 typedef struct pipe_t {
-    int fd;
+    int fd[2];
     char buffer[PIPE_MAX_SIZE];
     int current;
     char name[MAX_NAME];
@@ -19,7 +19,7 @@ typedef struct node_t {
     struct node_t * next;
 } node_t;
 
-pipe_t * openPipe(char * name);
+char openPipe(int * fds, char * name);
 void writePipe(int fd, char c);
 char readPipe(int fd);
 

Kernel/include/schedulerLib.h

@@ -4,7 +4,7 @@
 #include <stdint.h>
 
 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);
 char block(int pid);
 char unblock(int pid);
 char kill(int pid);

Kernel/include/video.h

@@ -10,5 +10,6 @@ void backspace();
 void clear();
 void increment();
 void changeWindow();
+void scroll();
 
 #endif

Kernel/interruptions/systemCalls.c

@@ -15,12 +15,11 @@
 
 uint64_t write(uint64_t fd, uint64_t buffer, uint64_t length) {
     char * bufferAux = (char *) buffer;
-    int color;
+    int color = STDOUT_COLOR;
 
-    if (fd == STDOUT)
-        color = STDOUT_COLOR;
-    else {
     fd = getFdOut();
+
+    if (fd != STDOUT) {
         int i = 0;
 	    while (bufferAux[i] != '\0' && i++ <= length) {
             writePipe(fd, bufferAux[i]);
@@ -35,6 +34,7 @@ uint64_t read(uint64_t fd, uint64_t buffer, uint64_t length) {
     char * bufferAux = (char *) buffer;
     int readBytes = 0;
 
+    fd = getFdIn();
 
     if (fd == STDIN) {
         while (length-- > 0) {

Kernel/interruptions/systemCallsDispatcher.c

@@ -5,9 +5,10 @@
 void exitProcess();
 // void setFn(uint64_t, uint64_t, uint64_t);
 char * processes();
-void enqueueProcess(uint64_t, uint64_t, uint64_t, uint64_t);
+void enqueueProcess(uint64_t, uint64_t, uint64_t, uint64_t, uint64_t);
+char openPipe(int *, char *);
 
-uint64_t systemCallsDispatcher(uint64_t rdi, uint64_t rsi, uint64_t rdx, uint64_t rcx, uint64_t r8) {
+uint64_t systemCallsDispatcher(uint64_t rdi, uint64_t rsi, uint64_t rdx, uint64_t rcx, uint64_t r8, uint64_t r9) {
 	switch (rdi) {
 		case 0:
             return write(rsi, rdx, rcx);
@@ -17,7 +18,7 @@ uint64_t systemCallsDispatcher(uint64_t rdi, uint64_t rsi, uint64_t rdx, uint64_
             return getTime(rsi, rdx, rcx);
         case 3:
             // createProcess(rsi);
-            enqueueProcess(rsi, rdx, rcx, r8);
+            enqueueProcess(rsi, rdx, rcx, r8, r9);
             break;
         case 4:
             exitProcess();
@@ -34,6 +35,8 @@ uint64_t systemCallsDispatcher(uint64_t rdi, uint64_t rsi, uint64_t rdx, uint64_
         case 9:
             vPortFree(rsi);
             break;
+        case 10:
+            return (uint64_t) openPipe(rsi, rdx);
         default:
             return -1;
 	}

Kernel/kernel.c

@@ -141,7 +141,7 @@ void test_mm(){
   } 
 }
 
-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);
 void initScheduler();
 
 void _cli();
@@ -177,7 +177,7 @@ int main() {
 
 	// ((EntryPoint)sampleCodeModuleAddress)();
     char * argv[] = {"SampleCode"};
-    enqueueProcess(sampleCodeModuleAddress, 1, 1, argv);
+    enqueueProcess(sampleCodeModuleAddress, 1, 1, argv, NULL);
 	clear();
 	// haltcpu();
 	_sti();

Kernel/utils/memManagerFRT4.c

@@ -199,14 +199,14 @@ void *pvReturn = NULL;
 			}
 					else {
 
-							ncNewline();
+							// ncNewline();
 				// ncPrint("MALLOC: ");
 				// ncPrintDec(xFreeBytesRemaining);
 				// ncPrint(" ");
 				// ncPrintDec(xWantedSize);
 				// ncPrint(" ");
 				// ncPrintDec(configADJUSTED_HEAP_SIZE);
-							ncNewline();
+							// ncNewline();
 					}
 		}
 

Kernel/utils/pipe.c

@@ -4,14 +4,19 @@ int fds = 2;
 
 node_t * firstPipe;
 
-pipe_t * openPipe(char * name) {
+char openPipe(int fds[2] ,char * name) {
     pipe_t * pipe = pvPortMalloc(sizeof(pipe_t));
     strcpy(pipe->name, name);
-    pipe->fd = fds++;
-    if ((pipe->sem = semOpen(SEM_NAME, 1)) == NULL)
-        return NULL;
     
-    return pipe;
+    if ((pipe->sem = semOpen(SEM_NAME, 1)) == NULL)
+        return EXIT_FAILURE;
+
+    pipe->fd[0] = fds++;
+    pipe->fd[1] = fds++;
+    fds[0] = pipe->fd[0];
+    fds[1] = pipe->fd[1];
+
+    return EXIT_SUCCESS;
 }
 
 void writePipe(int fd, char c) {
@@ -47,7 +52,7 @@ void closePipe(int fd) {
     semWait(del->pipe->sem);
     if (prev != NULL)
         prev->next = del->next;
-    else firstPipe->next = del->next;
+    else firstPipe = del->next;
 
     vPortFree(del->pipe);
     vPortFree(del);
@@ -69,9 +74,5 @@ node_t * searchPipe(node_t ** previous, int fd) {
         * previous = NULL;
         return NULL;
     }
-    if (curr == firstPipe) {
-        * previous = NULL;
-        return curr;
-    }
     return curr;
 }

Kernel/utils/scheduler.c

@@ -18,8 +18,8 @@ typedef struct processCDT {
     char foreground;
     enum states state;
     int * fd;
-    void * sseBytes;
+    // void * sseBytes;
-    void * fpuBytes;
+    // void * fpuBytes;
 } processCDT;
 
 processCDT * firstReady = NULL;
@@ -61,7 +61,7 @@ void idle() {
 
 void initScheduler() {
     char * argv[] = {"Idle"};
-    enqueueProcess(idle, 0, 1, argv);
+    enqueueProcess(idle, 0, 1, argv, NULL);
 }
 
 // void setFn(void (*fn) (int, char **), int argc, char *argv[]) {
@@ -69,8 +69,14 @@ void initScheduler() {
     // _initialize_stack_frame(fn, currentProcess->rbp, argc, argv);
 // }
 
-void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[]) {
+// 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]) {
+void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[], int * fd) {
+    if (fd == NULL) {
+        int * aux = pvPortMalloc(2);
+        aux[0] = 0;
+        aux[1] = 1;
+        fd = aux;
+    }
     if (firstReady != NULL && firstReady->pid == IDLE_PID)
         block(IDLE_PID);
 
@@ -81,7 +87,6 @@ void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *
     
     char priority = (foreground == 1) ? DEF_PRIORITY : MAX_PRIORITY/2;
 
-    // newProcess(process, argv[0], priority, foreground, (uint64_t) rsp, (uint64_t) rbp);
     // char aux[MAX_NAME_SIZE];
     char * aux = pvPortMalloc(10);
     int j;
@@ -99,6 +104,7 @@ void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *
     process->executions = 0;
     process->foreground = foreground;
     process->state = READY;
+    process->fd = fd;
     // process->sseBytes = pvPortMalloc(64);
     // process->fpuBytes = pvPortMalloc(14);
 
@@ -111,49 +117,20 @@ void enqueueProcess(void (*fn) (int, char **), char foreground, int argc, char *
         lastReady->next = process;
     lastReady = process;
         
-    // ncClear();
-    // ncPrint(argv[0]);
-    // // proc->name = argv[0];
-    // ncPrint(process->name);
-    // ncPrintDec(process->pid);
-    // ncPrintHex(process->rsp);
-    // ncPrintHex(process->rbp);
-    // wait(3);
     return;
 }
 
-void * getSSEaddress() {
+// void * getSSEaddress() {
-    return currentProcess->sseBytes;
+//     return currentProcess->sseBytes;
-}
+// }
 
-void * getFPUaddress() {
+// void * getFPUaddress() {
-    return currentProcess->fpuBytes;
+//     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;
-    // for (j = 0; j < MAX_NAME_SIZE - 1 && name[j] != 0; j++) {
-    //     aux[j] = name[j];
-    // }
-    // aux[j] = '\0';
-
-    // process->name = aux;
-    // process->pid = pids++;
-    // process->ppid = currentProcess->pid;
-    // process->priority = priority;
-    // process->rsp = rsp;
-    // process->rbp = rbp;
-    // process->executions = 0;
-    // process->foreground = foreground;
-    // process->state = READY;
 }
 
-// void loader(int argc, char * argv[], void (*fn) (int, char **)) {
-//     fn(argc, argv);
-//     exit();
-// }
-
 processADT searchProcess(processADT * previous, int pid, processADT first) {
     processADT curr = first;
     * previous = NULL;
@@ -168,10 +145,6 @@ processADT searchProcess(processADT * previous, int pid, processADT first) {
         * previous = NULL;
         return NULL;
     }
-    if (curr == first) {
-        * previous = NULL;
-        return curr;
-    }
     return curr;
 }
 
@@ -263,13 +236,13 @@ char kill(int pid) {
 
 int getFdOut() {
     if (currentProcess == NULL)
-        return NULL;
+        return EXIT_FAILURE;
     return currentProcess->fd[1];
 }
 
 int getFdIn() {
     if (currentProcess == NULL)
-        return NULL;
+        return EXIT_FAILURE;
     return currentProcess->fd[0];
 }
 

Userland/SampleCodeModule/asm/libasm.asm

@@ -3,7 +3,7 @@ GLOBAL _getMem, sys_loadProcess
 GLOBAL raiseOpcodeExc
 GLOBAL _getRegs, sys_switchContext
 GLOBAL cpu_id, cpu_id_support
-GLOBAL sys_exit, sys_ps, sys_free, sys_malloc, sys_sem
+GLOBAL sys_exit, sys_ps, sys_free, sys_malloc, sys_sem, sys_openPipe
 
 section .text
 
@@ -55,6 +55,27 @@ sys_read:
     pop rbp
     ret
 
+sys_openPipe:
+    push rbp
+    mov rbp, rsp
+
+	push rdi
+	push rsi
+	push rdx
+
+	mov rdx, rsi
+	mov rsi, rdi
+	mov rdi, 10
+	int 80h
+
+	pop rdx
+	pop rsi
+	pop rdi
+
+    mov rsp, rbp
+    pop rbp
+    ret
+
 sys_exit:
     push rbp
     mov rbp, rsp
@@ -274,7 +295,9 @@ sys_loadProcess:
 	push rdx
 	push rcx
 	push r8
+	push r9
 
+	mov r9, r8
 	mov r8, rcx
 	mov rcx, rdx
 	mov rdx, rsi
@@ -282,6 +305,7 @@ sys_loadProcess:
 	mov rdi, 3
     int 80h
 
+	pop r9
 	pop r8
 	pop rcx
 	pop rdx

Userland/SampleCodeModule/include/system.h

@@ -2,13 +2,15 @@
 #define SYSTEM_H
 
 // void sys_switchContext();
-// void sys_loadProcess();
+void sys_loadProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[], int * fd);
 int sys_time(char);
+void sys_exit();
 void sys_write(int, char *, int);
 char sys_read(int, char *, int);
 char * sys_ps();
 char * sys_sem();
 void * sys_malloc(int);
 void * sys_free(void *);
+void * sys_openPipe(int *, char *);
 
 #endif

Userland/SampleCodeModule/libc.c

@@ -28,6 +28,15 @@ int strcmp(const char * s1, const char * s2) {
     return *s1 - *s2;
 }
 
+char * strcat(char * dest, const char * src) {
+    char * rdest = dest;
+
+    while (*dest)
+      dest++;
+    while (*dest++ = *src++);
+    return rdest;
+}
+
 void putChar(char c){
     char buffer = c;
     sys_write(1, &buffer, 0);

Userland/SampleCodeModule/sampleCodeModule.c

@@ -1,8 +1,9 @@
 /* sampleCodeModule.c */
 #include "libc.h"
 #include "shell/include/shell.h"
+#include <stddef.h>
 
-void sys_loadProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[]);
+void sys_loadProcess(void (*fn) (int, char **), char foreground, int argc, char *argv[], int * fd);
 void sys_exit();
 // void sys_switchContext();
 
@@ -10,7 +11,7 @@ int main(int argc, char *argv[]) {
     winClear();
 
     char * argv2[] = {"BottlerSh"};
-    sys_loadProcess(shell, 1, 1, argv2);
+    sys_loadProcess(shell, 1, 1, argv2, NULL);
     // sys_loadProcess(shell);
 
     // sys_switchContext();

Userland/SampleCodeModule/shell/commands/cat.c

@@ -0,0 +1,17 @@
+#include "cat.h"
+
+#define SIZE 1000
+
+void cat(int argc, char ** argv) {
+    char c;
+    int i = 0;
+    char buffer[SIZE] = {0};
+    while ((c = getChar()) != 0 && c != -1) {
+        if (i >= SIZE)
+            break;
+        buffer[i++] = c;
+    }
+
+    printStringLen(buffer, i);
+    sys_exit();
+}

Userland/SampleCodeModule/shell/commands/clear.c

@@ -2,6 +2,7 @@
 #include "shell.h"
 #include "clear.h"
 
-void clear() {
+void clear(int argc, char *argv[]) {
     winClear();
+    sys_exit();
 }

Userland/SampleCodeModule/shell/commands/cpuid.c

@@ -100,11 +100,12 @@ 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() {
+void cpufeatures(int argc, char *argv[]) {
     for (int i = 0; i < len; i++) {
         if (checks[i]()) {
             printString(supports[i]);
 	        new_line();
         }
     }
+    sys_exit();
 }

Userland/SampleCodeModule/shell/commands/excDiv.c

@@ -1,6 +1,6 @@
 #include "excDiv.h"
 
-void excdiv() {
+void excdiv(int argc, char *argv[]) {
     int cero = 0;
     int res = 1/cero;
     res = res + 1;

Userland/SampleCodeModule/shell/commands/excOP.c

@@ -2,6 +2,6 @@
 
 void raiseOpcodeExc();
 
-void excop() {
+void excop(int argc, char *argv[]) {
     raiseOpcodeExc();
 }

Userland/SampleCodeModule/shell/commands/filter.c

@@ -0,0 +1,22 @@
+#include "filter.h"
+
+#define SIZE 1000
+
+int isVocal(char c) {
+    return c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U' || c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u';
+}
+
+void filter(int argc, char ** argv) {
+    char c;
+    int i = 0;
+    char buffer[SIZE] = {0};
+    while ((c = getChar()) != 0 && c != -1) {
+        if (i >= SIZE)
+            break;
+        if (isVocal(c))
+            buffer[i++] = c;
+    }
+
+    printStringLen(buffer, i);
+    sys_exit();
+}

Userland/SampleCodeModule/shell/commands/help.c

@@ -4,9 +4,10 @@
 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 = 9;
 
-void help() {
+void help(int argc, char *argv[]) {
     for (int i = 0; i < len; i++) {
         printString(info[i]);
         new_line();
     }
+    sys_exit();
 }

Userland/SampleCodeModule/shell/commands/inforeg.c

@@ -10,7 +10,7 @@ static char * regsNames[] = {
 	"R8: ", "R9: ", "R10: ", "R11: ", "R12: ", "R13: ", "R14: ", "R15: ",
 	"RSP: ", "RIP: "};
 
-void inforeg() {
+void inforeg(int argc, char *argv[]) {
 	uint64_t * regs = (uint64_t *) _getRegs();
 
 	char bufferAux[20];
@@ -25,4 +25,5 @@ void inforeg() {
 			printStringLen(" - ", 3);
 	}
 	new_line();
+	sys_exit();
 }

Userland/SampleCodeModule/shell/commands/printmem.c

@@ -13,10 +13,16 @@ void getMem(int * buffer, int initialAddress) {
     }
 }
 
-void printmem(long dir) {
+// void printmem(long dir) {
+void printmem(int argc, char *argv[]) {
+	if (argc != 2) {
+		printStringLen("printmem receives a memory position\n", 37);
+		return;
+	}
+
 	int buffer[8];
 	
-	getMem(buffer, dir);
+	getMem(buffer, atoi(argv[1], strlen(argv[1])));
 	
 	for (int i = 0; i < 8; i++) {
 		char bufferAux[8];

Userland/SampleCodeModule/shell/commands/ps.c

@@ -1,9 +1,9 @@
 #include "libc.h"
 #include "shell.h"
 
-void ps() {
+void ps(int argc, char *argv[]) {
     char * output = sys_ps();
     printString(output);
     new_line();
-    // sys_free(output);
+    sys_free(output);
 }

Userland/SampleCodeModule/shell/commands/quadratic.c

@@ -2,8 +2,14 @@
 #include "quadratic.h"
 #include "shell.h"
 
-void quadratic(double a, double b, double c) {
+// void quadratic(double a, double b, double c) {
-    double sol1, sol2;
+void quadratic(int argc, char *argv[]) {
+    if (argc != 4) {
+        printStringLen("quadratic receives 3 doubles\n", 30);
+        return;
+    }
+    
+    double sol1, sol2, a = atof(argv[1]), b = atof(argv[2]), c = atof(argv[3]);
     if (a == 0) {
         printStringLen("First argument cannot be 0\n", 28);
         return;

Userland/SampleCodeModule/shell/commands/semCom.c

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

Userland/SampleCodeModule/shell/commands/time.c

@@ -35,7 +35,7 @@ void printTime(int number) {
     printString(buffer);
 }
 
-void time(char * window, int * offset) {
+void time(int argc, char *argv[]) {
     printTime(getDay());
     putChar('/');
     printTime(getMonth());

Userland/SampleCodeModule/shell/commands/wc.c

@@ -0,0 +1,18 @@
+#include "wc.h"
+
+#define SIZE 1000
+
+void wc(int argc, char ** argv) {
+    char c;
+    int i = 0;
+    char buffer[SIZE] = {0};
+    while ((c = getChar()) != 0 && c != -1) {
+        if (i >= SIZE)
+            break;
+        if (c == '\n')
+            i++;
+    }
+
+    printStringLen(gtoa(i, buffer, 10, SIZE), SIZE);
+    sys_exit();
+}

Userland/SampleCodeModule/shell/include/cat.h

@@ -0,0 +1,9 @@
+#ifndef CAT_LIB
+#define CAT_LIB
+
+#include "libc.h"
+#include "system.h"
+
+void cat(int argc, char *argv[]);
+
+#endif

Userland/SampleCodeModule/shell/include/clear.h

@@ -1,6 +1,6 @@
 #ifndef CLEAR_LIB
 #define CLEAR_LIB
 
-void clear();
+void clear(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/cpu_id.h

@@ -71,7 +71,7 @@ enum {
 
 };
 
-void cpufeatures();
+void cpufeatures(int argc, char *argv[]);
 int cpu_id_support(void);
 
 #endif

Userland/SampleCodeModule/shell/include/excDiv.h

@@ -1,6 +1,6 @@
 #ifndef EXCDIV_LIB
 #define EXCDIV_LIB
 
-void excdiv();
+void excdiv(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/excOP.h

@@ -1,6 +1,6 @@
 #ifndef EXCOP_LIB
 #define EXCOP_LIB
 
-void excop();
+void excop(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/filter.h

@@ -0,0 +1,9 @@
+#ifndef FILTER_LIB
+#define FILTER_LIB
+
+#include "libc.h"
+#include "system.h"
+
+void filter(int argc, char *argv[]);
+
+#endif

Userland/SampleCodeModule/shell/include/help.h

@@ -1,6 +1,6 @@
 #ifndef HELP_LIB
 #define HELP_LIB
 
-void help();
+void help(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/inforeg.h

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

Userland/SampleCodeModule/shell/include/printmem.h

@@ -1,6 +1,6 @@
 #ifndef MEM_LIB
 #define MEM_LIB
 
-void printmem(long);
+void printmem(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/ps.h

@@ -1,6 +1,6 @@
 #ifndef PS_LIB
 #define PS_LIB
 
-void ps();
+void ps(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/quadratic.h

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

Userland/SampleCodeModule/shell/include/semCom.h

@@ -1,6 +1,6 @@
 #ifndef SEM_LIB
 #define SEM_LIB
 
-void sem();
+void sem(int argc, char *argv[]);
 
 #endif

Userland/SampleCodeModule/shell/include/time.h

@@ -7,7 +7,7 @@ int getHours();
 int getDays();
 int getMonths();
 int getYears();
-void time();
+void time(int argc, char *argv[]);
 
 #define SECONDS 0
 #define MINUTES 2

Userland/SampleCodeModule/shell/include/wc.h

@@ -0,0 +1,9 @@
+#ifndef WC_LIB
+#define WC_LIB
+
+#include "libc.h"
+#include "system.h"
+
+void wc(int argc, char *argv[]);
+
+#endif

Userland/SampleCodeModule/shell/shell.c

@@ -10,19 +10,45 @@
 #include "quadratic.h"
 #include "cpu_id.h"
 #include "ps.h"
+#include "wc.h"
+#include "filter.h"
+#include "cat.h"
 #include "semCom.h"
+#include "stddef.h"
+#define EXIT_FAILURE 1
+#define EXIT_SUCCESS 0
 
 #define SIZE 100
-#define MAX_ARGS 5
+#define MAX_ARGS 11
 
 #define COLS 80
 #define ROWS 25
 
-const int len = 9;
+typedef struct cmd_t {
-char *commands_void[] = {"help", "time", "inforeg", "excdiv", "excop", "clear", "cpufeatures", "ps", "sem"};
+    char * name;
-void (*func []) () = {help, time, inforeg, excdiv, excop, clear, cpufeatures, ps, sem};
+    void (*func) (int argc, char * argv[]);
+    char isBuiltIn;
+} cmd_t;
 
-void scanfNoPrint(char * buffer) {
+const int len = 14;
+cmd_t commands[] = {
+    { "help", help, 1 },
+    { "cat", cat, 0 },
+    { "time", time, 1 },
+    { "inforeg", inforeg, 1 },
+    { "excdiv", excdiv, 1 },
+    { "excop", excop, 1 },
+    { "filter", filter, 0 },
+    { "clear", clear, 1 },
+    { "cpufeatures", cpufeatures, 1 },
+    { "ps", ps, 1 },
+    { "sem", sem, 1 },
+    { "quadratic", quadratic, 0 },
+    { "printmem", printmem, 0 },
+    { "wc", wc, 0 },
+};
+
+int scanfNoPrint(char * buffer) {
     char c;
     int i = 0;
     while ((c = getChar()) != '\n' && i < SIZE - 1) {
@@ -38,52 +64,89 @@ void scanfNoPrint(char * buffer) {
         }
     }
     buffer[i] = '\0';
+    return i;
 }
 
-void shell(int argc, char *argv[]) {
+void processInput(char * input) {
-    while (1) {
+    int comm_flag0 = 0, comm_flag1 = 0, pipe = -1, end = -1;
-        int comm_flag = 0;
-        printStringLen("$> ", 3);
-        char buffer[SIZE] = {0};
-        scanfNoPrint(buffer);
-        new_line();
     char* tokens[SIZE] = {0};
-        tokens[0] = strstrip(buffer, ' ');
+    tokens[0] = strstrip(input, ' ');
     for (int i = 1; i < MAX_ARGS; i++) {
         tokens[i] = strtok(tokens[i - 1], ' ');
+        if (i > 1) {
+            if (!strcmp(tokens[i - 1], "|"))
+                pipe = i - 1;
+        }
+        if (tokens[i][0] == 0) {
+            end = i;
+            break;
+        }
+    }
+    int fd[2];
+    if (pipe != -1) {
+        if (sys_openPipe(fd, "pipe"))
+            return;
+            // return EXIT_FAILURE;
+    }
+    char ** argv0 = NULL;
+    char ** argv1 = NULL;
+    if (pipe != -1) {
+        argv0 = sys_malloc(sizeof(char *) * pipe);
+        for (int i = 0; i < pipe; i++)
+            argv0[i] = tokens[i];
+        argv1 = sys_malloc(sizeof(char *) * (end - pipe - 1));
+        for (int i = pipe + 1; i < end - pipe - 1; i++)
+            argv1[i] = tokens[i];
+    }
+    else {
+        *argv0 = sys_malloc(sizeof(char *) * end);
+        for (int i = 0; i < end; i++)
+            argv0[i] = tokens[i];
     }
     for (int i = 0; i < len; i++) {
-            if (!strcmp(tokens[0], commands_void[i])) {
+        if (!strcmp(tokens[0], commands[i].name)) {
-                if (*tokens[1] != 0)
+            comm_flag0 = 1;
-                    incorrect_arg(tokens[0]);
+            if (pipe != -1)
+                sys_loadProcess(commands[i].func, 1, pipe, argv0, fd);
             else 
-                    (*func[i])();
+                sys_loadProcess(commands[i].func, 1, end, argv0, NULL);
-                comm_flag = 1;
+            break;
         }
     }
-        if (!strcmp(tokens[0], "quadratic")) {
+    if (comm_flag0 && pipe != -1) {
-            if (*tokens[4] != 0 || *tokens[3] == 0)
+        for (int i = 0; i < len; i++) {
-                incorrect_arg(tokens[0]);
+            if (!strcmp(tokens[pipe + 1], commands[i].name)) {
-            else if (!isFloat(tokens[1]) || !isFloat(tokens[2]) || !isFloat(tokens[3]))
+                comm_flag1 = 1;
-                incorrect_arg(tokens[0]);
+                sys_loadProcess(commands[i].func, 1, end - pipe - 1, argv1, fd);
-            else
+                break;
-                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]);
-            else {
-                int length = strlen(tokens[1]);
-                printmem(atoi(tokens[1], length));
         }
-            comm_flag = 1;
     }
 
-        if (!comm_flag) {
+    if (!comm_flag0) {
         if (*tokens[0] != 0)
             incorrect_comm(tokens[0]);
     }
+    else if (!comm_flag1 && pipe != -1) {
+        if (*tokens[pipe + 1] != 0)
+            incorrect_comm(tokens[pipe + 1]);
+    }
+}
+
+void loader(void (*fn) (int, char **), int argc, char * argv[]) {
+    fn(argc, argv);
+    sys_exit();
+}
+
+void shell(int argc, char *argv[]) {
+    printStringLen("$> ", 3);
+    char buffer[SIZE] = {0};
+
+    while (1) {
+        scanfNoPrint(buffer);
+        new_line();
+        processInput(buffer);
+        printStringLen("$> ", 3);
     }
 }