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fixed concats with pipes and error messages

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This commit is contained in:
eneller
2020-08-14 13:35:05 +02:00
parent 3cb70d6089
commit 9238047783
1 changed files with 65 additions and 69 deletions
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118
GdBShell.java
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@@ -7,17 +7,11 @@ import java.util.Scanner;
import static cTools.KernelWrapper.*;
//TODO find why some calls dont terminate
//TODO remove stringbuilders/buffers because they are unnecessary
//TODO implement auto source?
public class GdBShell {
public static void main(String[] args) {
System.out.println("Welcome!");
String shellPrefix = "EN@GdBShell:";//print actual user instead of EN??
int runningInt = 0;
@@ -41,7 +35,7 @@ public class GdBShell {
//gets rid of the home/user directory and builds a string
for (int i = 3; (i < directoryArray.length); i++) {
str = str + "/"+ directoryArray[i];
str = str + "/" + directoryArray[i];
}
System.out.print("(" + runningInt + ")");
printColor(shellPrefix, "purple", false);
@@ -88,7 +82,7 @@ public class GdBShell {
boolean singleCommand = true;
//execute possible concatenations
for (i=1; i < commandsArr.length; i++) {
for (i = 1; i < commandsArr.length; i++) {
singleCommand = false;
@@ -97,39 +91,21 @@ public class GdBShell {
if (prevValue == 0) {
printColor("Process exited without error", "green", true);
prevValue = parseRedirect(commandsArr[i]);
} else {
break;
}
}
if (prevValue == 0) {
printColor("Process exited without error", "green", true);
} else {
if (singleCommand == false) {
printColor("Stopped concatenation at command number " + (i - 1) + " \"" + String.join(" ", commandsArr[i - 1]) + "\":", "red", true);
}
switch (prevValue) {
case -1:
printColor("Pipe failed","red",true);
break;
case Integer.MIN_VALUE + 1://from execute()
printColor("Entered empty command", "red", true);
break;
case Integer.MIN_VALUE://from execute
printColor("Couldn't find executable assigned to \"" + Arrays.toString(commandsArr[i - 1]) + "\"", "red", true);
break;
default:
printColor("Exited with error code " + prevValue, "red", true);//everything else
}
if (prevValue != 0 && singleCommand == false) {
printColor("Stopped concatenation at command number " + (i - 1) + " \"" + String.join(" ", commandsArr[i - 1]) + "\"", "red", true);
}
return;
}
static int parseRedirect(String[] inputArray){//should take pipe and read/write,, add >> for append?
static int parseRedirect(String[] inputArray) {//should take pipe and read/write,, add >> for append?
//find last occurrences of < and >
int redirectInPos = -1;
int redirectOutPos = -1;
@@ -159,29 +135,26 @@ public class GdBShell {
//TODO look up error return value of OPEN to separate from no redirect initialized as -1
int fd_in = -1;
if (redirectInPos != -1) {
if (checkls(inputArray[redirectInPos + 1])) {
if (inputArray.length > redirectInPos + 1 && checkls(inputArray[redirectInPos + 1])) {
fd_in = open(inputArray[redirectInPos + 1], O_RDONLY);
} else {
return -10;
printColor("Error: Invalid input file path", "red", true);
return -1;
}//throw error because invalid input file
}
int fd_out = -1;
if (redirectOutPos != -1) {
fd_out = open(inputArray[redirectOutPos + 1], O_WRONLY | O_CREAT | O_TRUNC);//overwrite file if exists, create else
if (inputArray.length <= redirectOutPos + 1) {
printColor("Error: No output file specified after redirect output symbol", "red", true);
return -1;
}
}
String[] command = Arrays.copyOfRange(inputArray, 0, firstPos);
int returnValue = parsePipe(command, fd_in, fd_out);
//close potential files
/*
if (fd_in != -1) {
close(fd_in);
}
if (fd_out != -1) {
close(fd_out);
}*/
return returnValue;
}
@@ -189,11 +162,10 @@ public class GdBShell {
static int parsePipe(String[] inputArray, int fd_in, int fd_out) {
String[][] command = splitArray(inputArray, "|");
//for(int i=0;i<command.length;i++){System.out.println(Arrays.toString(command[i]));}
//execute commands
int returnValue;
int returnValue = 0;
//first command gets stdin
int lastIn = -1;
int[] pipe1fd = new int[2];//array to pass to pipe as out parameter, then contains the read end[0] and write end[1]
@@ -201,14 +173,21 @@ public class GdBShell {
int[] pipe3fd;
if (command.length > 1) {
returnValue = pipe(pipe1fd);
if(returnValue!=0){printColor("Error opening pipe","red", true);return returnValue;}
if (returnValue != 0) {
printColor("Error opening pipe", "red", true);
return returnValue;
}
returnValue = execute(command[0], fd_in,false, pipe1fd[1],true);//execute first command with potential input from file
returnValue = execute(command[0], fd_in, false, pipe1fd[1], true);//execute first command with potential input from file
for (int i = 1; i < command.length - 1; i++) {
returnValue = pipe(pipe2fd);
if(returnValue!=0){printColor("Error opening pipe","red", true);return returnValue;}
returnValue = execute(command[i], pipe1fd[0],true, pipe2fd[1],true);
if (returnValue != 0) {
printColor("Error opening pipe", "red", true);
return returnValue;
}
returnValue = greaterAbsolute(execute(command[i], pipe1fd[0], true, pipe2fd[1], true), returnValue);
//variable swap
pipe3fd = pipe2fd;
@@ -222,18 +201,15 @@ public class GdBShell {
}
// execute last (or only) command
returnValue = execute(command[command.length - 1], lastIn,true, fd_out,true);
returnValue = greaterAbsolute(execute(command[command.length - 1], lastIn, true, fd_out, true), returnValue);
return returnValue;
}
static int execute(String[] inputArray, int fd_in,boolean closefdIn, int fd_out, boolean closefdOut) {//0 for read, 1 for write
System.out.println(Arrays.toString(inputArray)+ " fd_in: "+fd_in+" fd_out: "+fd_out);
static int execute(String[] inputArray, int fd_in, boolean closefdIn, int fd_out, boolean closefdOut) {//0 for read, 1 for write
System.out.println(Arrays.toString(inputArray) + " fd_in: " + fd_in + " fd_out: " + fd_out);
int[] intArray = new int[]{Integer.MIN_VALUE};//to pass to the waitpid function
//split the Array into path and arguments
@@ -253,7 +229,8 @@ public class GdBShell {
path = which(input);//"/bin/"+input;
//}
} else {
return Integer.MIN_VALUE + 1;
printColor("Entered empty command", "red", true);
return -1;
}// internal error code
@@ -279,36 +256,47 @@ public class GdBShell {
}
//execute the program
if(execv(path, inputArray)<0){
if (execv(path, inputArray) < 0) {
printColor("execv fatal error", "red", true);
exit(1);
}
exit(0);
}
//papa process
else {
if (forkInt<0){
printColor("Error: fork", "red",true);
if (forkInt < 0) {
printColor("Error: fork() returned Error", "red", true);
return forkInt;
}
//close open files that only the child process needs
if(closefdIn&&fd_in!=-1){close(fd_in);}
if(closefdOut&&fd_out!=-1){close(fd_out);}
if (closefdIn && fd_in != -1) {
close(fd_in);
}
if (closefdOut && fd_out != -1) {
close(fd_out);
}
//wait for child
if(waitpid(forkInt, intArray, 0)<0){
printColor("Error: waiting for child", "red",true);
int f;
if ((f = waitpid(forkInt, intArray, 0)) < 0) {
printColor("Error " + f + ": waiting for child", "red", true);
exit(1);
}
if (intArray[0] == 0) {
printColor("Process exited without error", "green", true);
} else {
printColor("Process exited with error code " + intArray[0], "red", true);
}
}
} else {
printColor("Couldn't find executable assigned to \"" + inputArray[0] + "\"", "red", true);
}
return intArray[0];//contains Integer.MIN_VALUE if no program was found using the which command
return intArray[0];
}
public static ArrayList<Integer> findArrayOccurrence(Object[] oArr, Object o) {
@@ -333,6 +321,14 @@ public class GdBShell {
return sArr;
}
public static int greaterAbsolute(int a, int b) {
if (Math.abs(a) > Math.abs(b)) {
return a;
} else {
return b;
}
}
public static String which(String arguments) {
ProcessBuilder prcBuilder = new ProcessBuilder();