Initial code

commands.c

@@ -0,0 +1,11 @@
+void runCommand(char* str, struct Session* session)
+{
+	if(strcmp(str, "help") == 0)
+	{
+		output("NO HELP!", strlen("NO HELP!"));
+	}
+	else if(strcmp(str, "quit") == 0)
+	{
+		session->isActive = 0;
+	}
+}

he.c

@@ -0,0 +1,274 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+#include<unistd.h>
+#include<fcntl.h>
+#include<sys/stat.h>
+#include<sys/types.h>
+
+#include<string.h>
+
+#include<termios.h>
+
+#include "types.h"
+
+#include "commands.c"
+
+struct Session* newSession(char*);
+
+struct termios oldSettings;
+
+int main(int argc, char** args)
+{
+	/* Make sure we have only two arguments */
+	if(argc == 2)
+	{
+		/* Get the filename */
+		char* filename = *(args+1);
+
+		/* Create a new session */
+		struct Session* session = newSession(filename);
+
+		if(session)
+		{
+			/* Open the editor */
+			newEditor(session);
+
+			/* Free the session */
+			free(session);
+		}
+
+		
+	}
+	else
+	{
+		
+	}
+}
+
+void output(char* string, unsigned int length)
+{
+	write(0, string, length);
+}
+
+char getChar()
+{
+	char character;
+	int b = read(0, &character, 1);
+	return character;
+}
+
+void redraw(struct Session* session)
+{
+	/* Move cursor back home */
+	char cr = 13;
+	output(&cr, 1);
+
+	/* Print all the data */
+	output(session->data, session->size);
+
+	/* Move cursor back home */
+	output(&cr, 1);
+
+	unsigned int i = 0;
+	while(i < session->position)
+	{
+		char seq[3] = {27, 91, 67};
+		output(seq, 3);
+		i++;
+	}
+
+	
+}
+
+void newEditor(struct Session* session)
+{
+	/* First create a struct */
+	struct termios termy;
+
+	/* Get current attributes */
+	tcgetattr(0, &termy);
+
+	/* Save current tty settings for restoral later */
+	oldSettings = termy;
+
+	/* Set the tty input modes */
+	//tcflag_t inputFlags = 0;
+	termy.c_iflag = termy.c_iflag | IGNBRK;
+	termy.c_lflag = termy.c_lflag & ~ISIG;
+	termy.c_lflag = termy.c_lflag & ~ECHO;
+
+	cfmakeraw(&termy);
+	
+	/* Set the tty to raw mode */
+	tcsetattr(0, 0, &termy);
+
+	char isActive = 1;
+
+	/* Output the file as of now */
+	redraw(session);
+
+//output("hello world", strlen("hello world"));
+	while(session->isActive)
+	{
+		char s;
+		s=getChar();
+
+		if (s == 17)
+		{
+			session->isActive = 0;
+		}
+		/* Control */
+		else if(s == 27)
+		{
+			/* Arrow keys */
+			s=getChar();
+			if(s == 91)
+			{
+				s=getChar();
+				char seq[3];
+				/* Up arrow */
+				if(s == 65)
+				{
+				
+				}
+				/* Down arrow */
+				else if (s == 66)
+				{
+					
+				}
+				/* Right arrow */
+				else if(s == 67)
+				{
+					seq[0] = 27;
+					seq[1] = 91;
+					seq[2] = 67;
+
+					session->position++;
+				}
+				/* Left arrow */
+				else if (s == 68)
+				{
+					seq[0] = 27;
+					seq[1] = 91;
+					seq[2] = 68;
+
+					session->position--;
+				}
+
+			//	output(seq, 3);
+			//continue;
+				
+			}
+		}
+		/* Ctrl+D is command key */
+		else if(s == 4)
+		{
+			char* str = malloc(200);
+			*str = 0;
+
+			while(1)
+			{
+				s=getChar();
+
+				if(s==4)
+				{
+					break;
+				}
+				else
+				{
+					strncat(str, &s, 1);
+				}
+			}
+			output(str,strlen(str));
+
+			runCommand(str, session);
+			
+			
+			free(str);
+		}
+		else
+		{
+			/* Set data at current position */
+			*(session->data+session->position) = s;
+			/* TODO: As we type position increases */
+			session->position++;
+			//strncat(session->data, &s, 1);
+			session->size++;
+		}
+		
+		//printf("%c\n",s);
+		char* l = malloc(20);
+		sprintf(l, "%u", s);
+	//	output(l, strlen(l));
+	//	output(&s, 1);
+		
+
+		
+
+		/* Redraw */
+		redraw(session);		
+	}
+
+	char* bye = "Bye mate!";
+	output(bye, strlen(bye));
+
+	/* Restore the tty settings back to the original */
+	tcsetattr(0, 0, &oldSettings);
+	
+}
+
+struct Session* newSession(char* filename)
+{
+	/* Allocate the session */
+	struct Session* session = malloc(sizeof(struct Session));
+
+	/* Make sure it allocated */
+	if(session)
+	{
+		/* Open the file */
+		int fd = open(filename, O_CREAT|O_RDWR);
+
+		if(fd >= 0)
+		{
+			/* Set the file descriptor */
+			session->fd = fd;
+
+			/* Get the stat struct */
+			struct stat statStruct;
+
+			/* Fill stat struct */
+			fstat(fd, &statStruct);
+	
+			/* Set the initial size */
+			session->size = statStruct.st_size;
+
+			/* Allocate initial space for buffer */
+			/* TODO: Remove and be dynamic */
+			session->data = malloc(session->size+69);
+
+			/* Set the initial characters */
+			read(fd, session->data, session->size);
+
+			char* temp = malloc(session->size+1);
+			strncpy(temp, session->data, session->size);
+			//printf("%s", temp);
+			
+
+			/* Set initial position to 0 */
+			session->position = 5;
+
+			/* Set the session to active */
+			session->isActive = 1;
+
+			/* On success, return the pointer to the session */
+			return session;
+		}
+
+		/* On successful malloc, but file failure */
+		free(session);
+	}
+
+	/* On error */
+	return 0;
+}

types.h

@@ -0,0 +1,27 @@
+/**
+* Represents an open editor session.
+*
+* Consists of the file descriptor
+* associated with the open file
+* and the size of the file (this
+* is loaded once and changed accordingly
+* with respect to the changes writing
+* back to disk).
+*/
+
+struct Session
+{
+	/* Open file descriptor */
+	int fd;
+
+	/* Data pointer */
+	char* data;
+
+	/* Current size */
+	unsigned int size;
+
+	/* Position */
+	unsigned int position;
+
+	char isActive;
+};