Initial upload

Labs/Lab10/Makefile

+#
+# CSCI 315 Operating Systems Design
+# Author: L. Felipe Perrone
+# Date: 2011-04-21
+# Copyright (c) 2011 Bucknell University
+#
+# Permission is hereby granted, free of charge, to any individual or
+# institution obtaining a copy of this software and associated
+# documentation files (the "Software"), to use, copy, modify, and
+# distribute without restriction, provided that this copyright and
+# permission notice is maintained, intact, in all copies and supporting
+# documentation.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL BUCKNELL UNIVERSITY BE LIABLE FOR ANY CLAIM, DAMAGES
+# OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
+# OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+# compiler
+CC = gcc
+
+CFLAGS = -g -Wall
+
+EXE = file_stat read_dir
+
+all: $(EXE)
+
+file_stat: file_stat.o
+	$(CC) $(CFLAGS) -o file_stat file_stat.o
+
+file_stat.o: file_stat.c
+	$(CC) -c $(CFLAGS) file_stat.c
+
+read_dir: read_dir.o
+	$(CC) -o read_dir read_dir.o
+
+read_dir.o: read_dir.c
+	$(CC) -c $(CFLAGS) read_dir.c
+
+clean:
+	/bin/rm -f *~ *.o core $(EXE)

Labs/Lab10/fdump.c

+/*
+ * Lindsay Knupp
+ * 11/30/21
+ * Lab 10- fdump.c
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+
+

Labs/Lab10/file_stat.c

+/*
+ * CSCI 315 Operating Systems Design
+ * Original developed by CSCI 315 staff
+ * Modified by: L. Felipe Perrone
+ * Date: 2011-4-21
+ * Copyright (c) 2011 Bucknell University
+ *
+ * Permission is hereby granted, free of charge, to any individual or
+ * institution obtaining a copy of this software and associated
+ * documentation files (the "Software"), to use, copy, modify, and
+ * distribute without restriction, provided that this copyright and
+ * permission notice is maintained, intact, in all copies and supporting
+ * documentation.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL BUCKNELL UNIVERSITY BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <grp.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <pwd.h>
+#include <time.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[]) {
+
+  // pointer to file name string
+  char *name;
+
+  // allocate tm structure to store retrieved time
+  struct tm time;
+
+  // allocate space to hold a string with retrieved time (ASCII text)
+  char asctime_str[35];
+
+  // container for complete set of file permission bits (binary)
+  unsigned int mode;
+
+  // container for the three bits of user permissions
+  unsigned int umode;
+
+  // container for the three bits of group permissions
+  unsigned int gmode;
+
+  // container for the three bits of owner permission
+  unsigned int omode;
+
+  // human readable file permissions (ASCII text)
+  char perm_bits_str[] = "---------";
+
+  // file descriptor 
+  unsigned int fd;
+
+  // structure to contain the result of the fstat call (info on this file)
+  struct stat file_info;
+
+  // structure to contain the result of the vfstat call (info on file system)
+  struct statvfs fs_info;
+  
+  // used to save the return value of realpath
+  char resolved_path[PATH_MAX];
+  char* ret_path;
+  
+  // check number of arguments for appropriate usage
+  if (2 != argc) {
+    printf(" usage: %s [file_name]\n", argv[0]);
+    exit(-11);
+  }
+
+  // post-condition: argv[1] contains name of file to use
+  
+  // try to open file
+  fd = open(argv[1], O_RDONLY);
+  if (-1 == fd) {
+    perror("Failed to open read only file - ");
+    exit(-1);
+  }
+  
+  // use fstatvfs to learn details about the file system
+  if (fstatvfs(fd, &fs_info) == 0) {
+      printf("== FILE SYSTEM INFO ============================\n");
+      printf(" file system fstatvfs() call successful\n");
+      printf(" file system block size: %d\n", 0); // TO-DO
+      printf(" max. file name length: %d\n", 0); // TO-DO
+  } else {
+    printf("%s: File system fstatvfs call failed\n", argv[0]);
+    exit(-1);
+  }
+
+  // post-condition: maximum length of file name string is known
+
+  // use calloc to allocate space for file name string
+  name = calloc(fs_info.f_namemax, 1);
+
+  if (NULL == name) {
+    perror("Problem in calloc - ");
+    exit(-1);
+  }
+
+  // copy file name into name variable using secure version of string copy
+  strncpy(name, argv[1], 500);
+   
+  // use fstat to get information on specific file
+  if (fstat(fd, &file_info) == 0) {
+    printf("\n== FILE INFO ============================\n");
+    printf(" file fstat() call successful\n");
+    
+    // mode comes from the lower 9 bits in file_info.st_mode
+    mode = file_info.st_mode & 0x1FF;
+    
+    printf(" file protection bits = 0%o\n", mode);
+    
+    // umode comes from the high 3 bits in mode
+    umode = 0; // TO-DO
+    
+    // gmode comes from the middle 3 bits in mode
+    gmode = 0; // TO-DO
+    
+    // omode comes from the low 3 bits in mode
+    omode = 0; // TO-DO
+      
+    // once you have set umode, gmode, and omode, the code below
+    // will construct the right string for you and display it
+
+    // construct string with file protection information
+    if (umode & 0x4) perm_bits_str[0] = 'r';
+    if (umode & 0x2) perm_bits_str[1] = 'w';
+    if (umode & 0x1) perm_bits_str[2] = 'x';
+    
+    if (gmode & 0x4) perm_bits_str[3] = 'r';
+    if (gmode & 0x2) perm_bits_str[4] = 'w';
+    if (gmode & 0x1) perm_bits_str[5] = 'x';
+    
+    if (omode & 0x4) perm_bits_str[6] = 'r';
+    if (omode & 0x2) perm_bits_str[7] = 'w';
+    if (omode & 0x1) perm_bits_str[8] = 'x';
+    
+    printf(" file protection string = %s\n", perm_bits_str);
+    
+    printf(" file protection mode (u:g:o) = %o:%o:%o\n",
+	   umode, gmode, omode);
+    
+    printf(" owner user name = %s\n",""); // TO-DO: man getpwuid 
+    printf(" owner group name = %s\n", ""); // TO-DO: man getgrgid 
+    
+		// TO-DO: print "mode = x", where x may be:
+		// "regular file"
+		// "directory"
+		// "character device"
+		// "block device"
+		// "symbolic link"
+		// "socket"
+		// "fifo"
+		// "unknown"
+
+    if (S_ISREG(file_info.st_mode)) { 
+      printf(" mode = regular file\n");
+		} else { // see TO-DO above
+		}
+       
+    ret_path = realpath(name, resolved_path);
+    if (NULL != ret_path) 
+      printf(" absolute path = %s\n", ret_path);
+    else {
+      perror(" couldn't resolve path");
+      exit(-1);
+    }
+        
+    // fill in the time the last write was made to file
+    localtime_r(&(file_info.st_mtime), &time);      
+    asctime_r(&time, asctime_str);
+    printf(" time of last modification: %s\n", asctime_str);
+    
+    fflush(stdout);
+    close(fd);
+    exit(0);
+  }
+  else
+    printf(" fstat call failed\n");
+
+  return 0;
+}

Labs/Lab10/hexdump.c

+/*
+ * Copyright (c) 2012 Bucknell University
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: L. Felipe Perrone (perrone@bucknell.edu)
+ */
+
+#include <stdio.h>
+
+char is_printable(unsigned char c) {
+     if ((c >= 0x20) && (c < 0x7F))
+	  return c;
+     else
+	  return '.';
+}
+
+void hexdump(unsigned char* buffer, unsigned int length) {
+     int b=0, c=0;
+     int s, rem;
+
+     // b is a counter for the number of bytes (half the number of hex digits)
+
+     printf("\n     PAYLOAD HEXDUMP:\n");
+     while (b < length) {
+	  printf("\n     %07x:", b);
+	  for (; (b%16<15) && (b<length); b++) {
+	       if (0 == b % 2)
+		    printf(" ");
+	       printf("%02hhx", buffer[b]);
+	  }
+
+	  if (b < length)
+	       printf("%02hhx   ",  buffer[b++]);
+	  else { // print a number of spaces to align the remaining text
+	       rem = b % 16;
+	       for (s=0; s < 44 - ((rem*2) + (rem/2) + 1); s++)
+		    printf(" ");
+	  }
+
+	  for (;(c%16<15) && (c<length); c++) {
+	       printf("%c", is_printable(buffer[c]));
+	  }
+	  if (c<length)
+	       printf("%c", is_printable(buffer[c++]));
+     }
+}

Labs/Lab10/hexdump.h

+/*
+ * Copyright (c) 2012 Bucknell University
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: L. Felipe Perrone (perrone@bucknell.edu)
+ */
+
+#ifndef __HEXDUMP_H__
+#define __HEXDUMP_H__
+
+/**
+ * This function prints to stdout the contents of a buffer in hexadecimal
+ * and in its ASCII representation. The output is similar to what you would
+ * get by running the Linux utility xxd on a file.
+ *
+ * @param buffer pointer to a memory buffer
+ * @param length number of bytes in the buffer
+ */
+extern void hexdump(unsigned char* buffer, unsigned int length);
+
+#endif /* __HEXDUMP_H__ */

Labs/Lab10/prelab.txt

+Lindsay Knupp
+11/30/21
+Lab 10 - prelab.txt
+
+

Labs/Lab10/read_dir.c

+/*
+ * CSCI 315 Operating Systems Design
+ * Original developed by CSCI 315 staff
+ * Modified by: L. Felipe Perrone
+ * Date: 2011-4-21
+ * Copyright (c) 2011 Bucknell University
+ *
+ * Permission is hereby granted, free of charge, to any individual or
+ * institution obtaining a copy of this software and associated
+ * documentation files (the "Software"), to use, copy, modify, and
+ * distribute without restriction, provided that this copyright and
+ * permission notice is maintained, intact, in all copies and supporting
+ * documentation.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL BUCKNELL UNIVERSITY BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "read_dir.h"
+
+// function prototypes
+void process(char *name);
+void enqueue(char *name, que_t *q);
+void dequeue(que_t *q);
+void peek_front(char *name,que_t q);
+bool queue_empty(que_t q);
+void initq(que_t *q);
+
+// main function
+int main(int argc,char *argv[]) {
+
+  if (2 != argc) {
+    printf(" usage: %s dirpath\n", argv[0]);
+    exit(-1);
+  }
+  else {
+    // pass in the starting directory
+    process(argv[1]);       
+  }
+  
+  return 0;
+}
+
+// traverse a directory tree applying a function when a file is found
+void process(char *root)
+{
+  int numOfFiles = 0;
+  que_t nameq;
+  char dname[MAXLENGTH];
+  char cname[MAXLENGTH];
+  char prefix[MAXLENGTH];
+
+  struct dirent *dp;
+  DIR *dirp;
+
+    initq(&nameq);
+    enqueue(root,&nameq);
+
+    while (true != queue_empty(nameq)) {
+      peek_front(dname,nameq); 
+      dequeue(&nameq);
+      
+      dirp = opendir(dname);
+      if (dirp != NULL) { // it is a directory
+
+	printf("directory : %s\n",dname);
+	strncpy(prefix, dname, MAXLENGTH);
+	strncat(prefix,"/", MAXLENGTH);
+	
+	for (dp = readdir(dirp); NULL != dp; dp = readdir(dirp)) {
+	  if ((strcmp(dp->d_name,"..") != 0) && 
+	      (strcmp(dp->d_name,".") != 0)) {
+	    
+	    // prevent from infinite loop
+	    strncpy(cname, prefix, MAXLENGTH);
+	    
+	    // concatenate the prefix
+	    strncat(cname, dp->d_name, MAXLENGTH);  
+	    enqueue(cname,&nameq);
+	  }
+	}
+	closedir (dirp);
+      } else { 
+	// test if it is a regular file and not a device or link -- TO-DO
+	// if this is a regular file, then process it -- TO-DO
+	printf(" processing file: %s\n", dname);
+	numOfFiles++;
+      }      
+    } // while
+    
+    printf(" a total of %d files were counted\n",numOfFiles);
+}
+
+// initialize queue data structure
+void initq(que_t *q) {
+  q->head = q->tail = NULL;
+}
+
+// test whether queue data structure is empty
+bool queue_empty(que_t q) {
+  if (NULL == q.head) {
+     return true;
+  } else {
+    return false;
+  }
+}
+
+// add an element to queue
+void enqueue(char *name, que_t *q) {
+  item_t *temp;
+  
+  temp = (item_t *)malloc(sizeof(item_t));
+  strncpy(temp->name,name,MAXLENGTH);
+  temp->next = NULL;
+  
+  if (true == queue_empty(*q)) {
+    q->head = temp;
+    q->tail = temp;
+  } else {
+    q->tail->next = temp;
+    q->tail = q->tail->next;
+  }
+}
+
+// remove an element from the front of the queue
+void dequeue(que_t *q) {
+  item_t *temp;
+  
+  if (true == queue_empty(*q)) {
+    printf(" error in dequeue \n");
+    exit(-1);
+  } else {
+    temp = q->head;
+    q->head = q->head->next;
+    free(temp);
+  }
+}
+
+// find element at front of queue without removing
+void peek_front(char *name, que_t q) {
+  if (true == queue_empty(q)) {
+    printf(" error in dequeue \n");
+     exit(-1);
+  } else {
+    strncpy(name, q.head->name, MAXLENGTH);
+  }
+} 

Labs/Lab10/read_dir.h

+/*
+ * CSCI 315 Operating Systems Design
+ * Original developed by CSCI 315 staff
+ * Modified by: L. Felipe Perrone
+ * Date: 2011-4-21
+ * Copyright (c) 2011 Bucknell University
+ *
+ * Permission is hereby granted, free of charge, to any individual or
+ * institution obtaining a copy of this software and associated
+ * documentation files (the "Software"), to use, copy, modify, and
+ * distribute without restriction, provided that this copyright and
+ * permission notice is maintained, intact, in all copies and supporting
+ * documentation.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL BUCKNELL UNIVERSITY BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+ * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
+ * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <sys/time.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdbool.h>
+
+#define MAXLENGTH 255 // for file names
+#define BYTE 8
+
+struct item_type 
+{
+   char name[MAXLENGTH];
+   int count;
+   struct item_type *next;
+};
+
+struct que_type
+{
+   struct item_type *head, *tail;
+};
+
+typedef struct que_type que_t;
+typedef struct item_type item_t;

Labs/Lab9/ishell.c

@@ -20,10 +20,13 @@ int main (int argc, char *argv[]){
 	int status;
 	
 	char path[1024];
+	char path2[1024];
 	char* saveptr;
 	char* str;
 	char* token;
 	char* tokens[MAXCNT];
+	char* tokens1[MAXCNT];
+	char* tokens2[MAXCNT];
 	char* line = NULL;		
 	size_t length;
 	
@@ -38,6 +41,8 @@ int main (int argc, char *argv[]){
 	
 	for (int i=0;i<MAXCNT;i++){
 		tokens[i] = (char*) malloc(MAXLEN);	
+		tokens1[i] = (char*) malloc(MAXLEN);
+		tokens2[i] = (char*) malloc(MAXLEN);
 	}
 
 	int token_count = 0;
@@ -49,9 +54,40 @@ int main (int argc, char *argv[]){
 		strcpy(tokens[token_count],token);
 		token_count ++;
 	}
-	tokens[token_count] = NULL;
 	
+	int command2 = 0;
+	for (int i = 0; i<MAXCNT; i++){
+		if(strcmp(tokens[i],";") == 0){
+			command2 = i;
+			break;
+		}
+	
+	}
+	//printf("command index %d\n",command2);
+
+	if (command2 != 0){
+	for (int i = 0; i < command2;i++){
+		strcpy(tokens1[i],tokens[i]);
+	}
+	tokens1[command2] = NULL;	
+	
+	for (int i = command2;i<token_count;i++){
+		strcpy(tokens2[i],tokens[i]);
+	}
+	tokens2[token_count] = NULL;
+	
+	strcpy(path2, "/usr/bin/");
 	strcpy(path, "/usr/bin/");
+
+	strcat(path, tokens1[0]);
+	strcat(path, tokens2[0]);
+
+
+	}
+
+	tokens[token_count] = NULL;
+	
+	
 	strcat(path,tokens[0]);
 
 	free(line);
@@ -63,6 +99,10 @@ int main (int argc, char *argv[]){
 
 	// child branch 
 	if (pid  == 0){