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#include <stdio.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdlib.h>
#include <math.h>

//this function will go into a separate file
//converting integer to strings
char *its(int num)
{
    //size of integer including '\0'
    int num_size;
    char *num_arr;

    num_size = (int)((ceil(log10(num))+1)*sizeof(char));
    num_arr = malloc(num_size);
    if (!num_arr)
        return (NULL);
    sprintf(num_arr, "%d", num);
    return (num_arr);
}
//this function will go into a separate file
int string_handler(va_list arg, char *ptr, int ptr_index)
{
    char *str;
    str = va_arg(arg, char *);
    while (*str != '\0') 
    {
        ptr[ptr_index] = *str;
        str++;
        ptr_index++;
    }
    return (ptr_index);
}
//this function will go into a separate file
int int_and_dec_handler(va_list arg, char *ptr, int ptr_index)
{
    int d;
    d = va_arg(arg, int);
    char *ptr2 = its(d);

    while (*ptr2 != '\0')
    {
        ptr[ptr_index] = *ptr2;
        ptr2++;
        ptr_index++;
    }
    free(its(d));
    return (ptr_index);
}
//this function will go into a separate file
int char_handler(va_list arg, char *ptr, int ptr_index)
{
    char c;

    c = (char)va_arg(arg, int);
    ptr[ptr_index] = c;
    ptr_index++;
    return (ptr_index);
}

int _printf(const char * const format,...)
{
    int i, buffer_index, bytes;
    char *buffer;
    va_list args;

    va_start(args, format);
    i = 0;
    buffer_index = 0;
    buffer = malloc(1024);
    if (!buffer)
    {
        perror("Memory allocation failure");
        exit(EXIT_FAILURE);
    }

    while (format[i] != '\0')
    {
        if (format[i] == '%')
        {
            i++;
            if (format[i] == 'c')
            {
                int char_call = char_handler(args, buffer, buffer_index);
                buffer_index = char_call;
            }
            else if (format[i] == 's')
            {
               int str_call = string_handler(args, buffer, buffer_index);
               buffer_index = str_call;
            }
            else if (format[i] == '%')
            {
                buffer[buffer_index] = '%';
                buffer_index++;
            }
            else if (format[i] == 'd' || format[i] == 'i')
            {
               int dec_call = int_and_dec_handler(args, buffer, buffer_index);
               buffer_index = dec_call;
            }
        }
        else
            {
                buffer[buffer_index] = format[i];
                buffer_index++;
            }
        i++;
    }

    buffer[buffer_index] = '\0';
    bytes = write(1, buffer, buffer_index);
    free(buffer);
    va_end(args);
    return (bytes);

}