examples/PIPS/FileAccessExample/fileaccessexample.c

// fileaccessexample.c
//
// Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// Component description file
//

// This example demonstrates the Symbian platform Platform Security model.
// This shows the restrictions on the directories that can be accessed by a program, 
// depending on the capabilities that the program has.

// Include files
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>

void PressAKey()
        {
        fflush(stdout);
        getchar();
        }
int DisplayErrorMessage(char msg[])
        {
        printf("%s [Error NUMBER = %d]\n",msg,errno);
        PressAKey();
        return EXIT_FAILURE;
        }
void CreateASecureDirectory()
        {
        int result;
        
        result = mkdir("mydirectory",S_IWUSR);     
        if(result == 0)
                {
                printf(" A secure directory for the program is created successfully\n");
                PressAKey();
                }
        else
                {
                DisplayErrorMessage("\nError in creating directory\n");
                PressAKey();
                }
        }
void WriteDataToAFile(char FileName[])
        {
        FILE* fp= NULL;
        
        fp = fopen(FileName, "w");
        if (fp== NULL)
                {
                DisplayErrorMessage("\nError in writing data in to the file=%d");
                PressAKey();
                }
        else
                {
                fprintf(fp,"%s","hello");
                fflush(fp);
                fclose(fp);
                printf(" Writing data in to the file from the secure directory is successful");
                }
        }

void ReadDataFromAFile(char FileName[])
        {
        FILE* fp= NULL;
        
        fp = fopen(FileName, "r");
        if (fp == NULL)
                {
        DisplayErrorMessage("\nError in reading data from the file = %d"); 
        printf(" Press any key to exit from the example");
        PressAKey();
                }
        else
                {
                char x[30];
                                
                // Seek to the beginning of the file
        fseek(fp, SEEK_SET, 0); 
        
        // Get the data present in file from the beginning 
                fscanf(fp,"%s",x);
                printf("\n Data present in the file is : %s",x);
                fclose(fp);
                printf("\n Reading data of the file from the directory is successful\n");
                }
        }
void RemoveADirectory(char FileName[])
        {
        int result;
        
        result = remove(FileName);
        if(result == 0)
                        {
                        printf(" Removing the file from the directory is successful\n");
                        }
                else
                        {
                        DisplayErrorMessage(" Error in removing the file from the directory=%d");
                        PressAKey();
                        }
        result = rmdir("mydirectory");
   
        if(result == 0)
                {
                printf(" Removing the the directory is successful\n");
                PressAKey();
                }
        else
                {
                DisplayErrorMessage(" Error in removing the directory=%d");
                PressAKey();
                }
        }
void WriteDataToFileOfAnotherProgram(char FileName[])
        {
        FILE* fp= NULL;
        
        fp = fopen(FileName, "w");
        
        if (fp == NULL)
                {
                printf(" Writing data to files in a private directory belonging to another program is not possible"); 
        }
        else
                {
                printf("\n Writing data to files in a private directory belonging to another program is possible"); 
                PressAKey();
                }
        }
void ReadDataFromFileOfAnotherProgram(char FileName[])
        {
        FILE* fp= NULL;
        
        fp = fopen(FileName, "r");
        
        if (fp == NULL)
                {
                printf("\n Reading data from files in a private directory belonging to another program is not possible"); 
                PressAKey();
                }
        else
                {
                printf("\n Reading data from files in a private directory belonging to another program is possible"); 
                PressAKey(); 
                }
        }
void WriteDataToFileOfSysBin(char FileName[])
        {
        FILE* fp= NULL;
        
        fp = fopen(FileName, "w");
        
        if (fp == NULL)
                {
                printf("\n Writing data to files in the sys/bin directory is not possible"); 
                }
        else
                {
                printf("\n Writing data to files in the sys/bin directory is possible"); 
                PressAKey();
                }
        }
void ReadDataToFileOfSysBin(char FileName[])
        {
        FILE* fp = NULL;
        
        fp = fopen(FileName, "r");
        
        if (fp == NULL)
                {
                printf("\n Reading data from files in the sys/bin directory is not possible"); 
                PressAKey();
                }
        else
                {
                printf("\n Reading data from files in the sys/bin directory is possible"); 
                printf(" Press any key to exit from the example");
                PressAKey(); 
                }       
        }

int main()
{
        char ownFileName[50] = "\\private\\e80000c9\\mydirectory\\myownfile.txt";
        char otherFileName[40] = "\\private\\e80000c8\\otherfile.txt";
        char sysBinFileName[30] = "\\sys\\bin\\euser.dll";
        
        printf("\n Welcome to the file access example using POSIX APIs\n");
        
        // Print the message to start the example application.
        printf("\n Press enter key to step through the example\n");
        PressAKey();
        
        // Call CreateASecureDirectory() function to create a secure directory for the program.
        CreateASecureDirectory();
        
        // Call WriteDataToAFile() function to write data in to a file from the created directory.
        WriteDataToAFile(ownFileName);
        
        // Call WriteDataToAFile() function to write data in to a file from the created directory.
        ReadDataFromAFile(ownFileName);
        
        // Call RemoveADirectory() function to remove the directory.
        RemoveADirectory(ownFileName);
        
        // Call WriteDataToFileOfAnotherProgram() function to write data in to a file of another program.
        WriteDataToFileOfAnotherProgram(otherFileName);
        
        // Call ReadDataFromFileOfAnotherProgram() function to read data from a file of another program.
        ReadDataFromFileOfAnotherProgram(otherFileName);
        
        // Call WriteDataToFileOfSysBin() function to write data in to a file of sys/bin directory.
        WriteDataToFileOfSysBin(sysBinFileName);
        
        // Call ReadDataFromFileOfSysBin() function to read data from a file in the sys/bin directory.
        ReadDataToFileOfSysBin(sysBinFileName);
        
        // Print the message to exit from the example application.
        printf("\n Press enter key to exit from the example application");
        PressAKey();
        
        // returns the success code.
        return EXIT_SUCCESS;
}

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