Recover - cs50 (problem set4)

recover.c

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <cs50.h>

bool foundNewJpgFile(uint8_t *buffer);

int main(int argc, char *argv[])
{
    if (argc != 2)
    {
        printf("Invalid filename provided. Please, provide one and only one forensic file name as expected.\n");
    
        return 1;
    }
  
    FILE *sourceFilePtr = fopen(argv[1], "r");
  
    if (!sourceFilePtr)
    {
        printf("Unable to read the given file. Reason: file doesn\'t exists or is unreadable.\n");
        
        fclose(sourceFilePtr);
        
        return 1;
    }

    int fileNumber = 0;

    bool isRecoveringJpgFile = false;

    char *recoveredFilename = malloc(sizeof(char) * 8);

    FILE *recoveredFile = NULL;

    uint8_t *buffer = malloc(sizeof(char) * 512);

    while (fread(buffer, sizeof(uint8_t), 512, sourceFilePtr))
    {
        if (foundNewJpgFile(buffer))
        {
            if (isRecoveringJpgFile)
            {
                fclose(recoveredFile);

                fileNumber++;
            }

            sprintf(recoveredFilename, "%03i.jpg", fileNumber);

            recoveredFile = fopen(recoveredFilename, "w+");
            
            if (!recoveredFile)
            {
                printf("Unable to start the recovery process. Reason: You may be running out of memory.\n");
            
                fclose(recoveredFile);
                
                return 1;
            }
            
            if (!isRecoveringJpgFile)
            {
                isRecoveringJpgFile = true;
            }
        }
        
        if (isRecoveringJpgFile)
        {
            fwrite(buffer, sizeof(char), 512, recoveredFile);
        }
    }

    free(buffer);
    fclose(recoveredFile);
    fclose(sourceFilePtr);
}

bool foundNewJpgFile(uint8_t *buffer)
{
    return buffer[0] == 0xff && buffer[1] == 0xd8 && buffer[2] == 0xff && (buffer[3] & 0xf0) == 0xe0;
}