0x0C-more_malloc_free

Requirements

General

• Allowed editors: vi, vim, emacs
• All your files will be compiled on Ubuntu 14.04 LTS
• Your programs and functions will be compiled with gcc 4.8.4 using the flags -Wall -Werror -Wextra and -pedantic
• All your files should end with a new line
• A README.md file, at the root of the folder of the project is mandatory
• Your code should use the Betty style. It will be checked using betty-style.pl and betty-doc.pl
• You are not allowed to use global variables
• No more than 5 functions per file
• You are not allowed to use the standard library. Any use of functions like printf, puts, etc… is forbidden
• You are allowed to use _putchar
• You don’t have to push _putchar.c, we will use our file. If you do it won’t be taken into account
• In the following examples, the main.c files are shown as examples. You can use them to test your functions, but you don’t have to push them to your repo (if you do we won’t take them into account). We will use our own main.c files at compilation. Our main.c files might be different from the one shown in the examples
• The prototypes of all your functions and the prototype of the function _putchar should be included in your header file called holberton.h
• Don’t forget to push your header file

Tasks

0. Trust no one

File: 0-malloc_checked.c

Write a function that allocates memory using malloc.

• Prototype: void *malloc_checked(unsigned int b);
• Returns a pointer to the allocated memory
• if malloc fails, the malloc_checked function should cause normal process termination with a status value of 98

julien@ubuntu:~/0x0b. more malloc, free$ cat 0-main.c
#include "holberton.h"
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>

/**
 * main - check the code for Holberton School students.
 *
 * Return: Always 0.
 */
int main(void)
{
    char *c;
    int *i;
    float *f;
    double *d;

    c = malloc_checked(sizeof(char) * 1024);
    printf("%p\n", (void *)c);
    i = malloc_checked(sizeof(int) * 402);
    printf("%p\n", (void *)i);
    f = malloc_checked(sizeof(float) * 100000000);
    printf("%p\n", (void *)f);
    d = malloc_checked(INT_MAX);
    printf("%p\n", (void *)d);
    free(c);
    free(i);
    free(f);
    free(d);
    return (0);
}
julien@ubuntu:~/0x0b. more malloc, free$ gcc -Wall -pedantic -Werror -Wextra 0-main.c 0-malloc_checked.c -o a
julien@ubuntu:~/0x0b. more malloc, free$ ./a 
0x1e39010
0x1e39830
0x7f31f6c19010
julien@ubuntu:~/0x0b. more malloc, free$ echo $?
98
julien@ubuntu:~/0x0b. more malloc, free$ 

1. string_nconcat

File: 1-string_nconcat.c

Write a function that concatenates two strings.

• Prototype: char *string_nconcat(char *s1, char *s2, unsigned int n);
• The returned pointer shall point to a newly allocated space in memory, which contains s1, followed by the first n bytes of s2, and null terminated
• If the function fails, it should return NULL
• If n is greater or equal to the length of s2 then use the entire string s2
• if NULL is passed, treat it as an empty string

julien@ubuntu:~/0x0b. more malloc, free$ cat 1-main.c
#include "holberton.h"
#include <stdio.h>
#include <stdlib.h>

/**
 * main - check the code for Holberton School students.
 *
 * Return: Always 0.
 */
int main(void)
{
    char *concat;

    concat = string_nconcat("Holberton ", "School !!!", 6);
    printf("%s\n", concat);
    free(concat);
    return (0);
}
julien@ubuntu:~/0x0b. more malloc, free$ gcc -Wall -pedantic -Werror -Wextra 1-main.c 1-string_nconcat.c -o b
julien@ubuntu:~/0x0b. more malloc, free$ ./b 
Holberton School
julien@ubuntu:~/0x0b. more malloc, free$

2. _calloc

File: 2-calloc.c

Write a function that allocates memory for an array, using malloc.

• Prototype: void *_calloc(unsigned int nmemb, unsigned int size);
• The _calloc function allocates memory for an array of nmemb elements of size bytes each and returns a pointer to the allocated memory.
• The memory is set to zero
• If nmemb or size is 0, then _calloc returns NULL
• If malloc fails, then _calloc returns NULL FYI: The standard library provides a different function: calloc. Run man calloc to learn more.

julien@ubuntu:~/0x0b. more malloc, free$ cat 2-main.c
#include "holberton.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/**
 * simple_print_buffer - prints buffer in hexa
 * @buffer: the address of memory to print
 * @size: the size of the memory to print
 *
 * Return: Nothing.
 */
void simple_print_buffer(char *buffer, unsigned int size)
{
    unsigned int i;

    i = 0;
    while (i < size)
    {
        if (i % 10)
        {
            printf(" ");
        }
        if (!(i % 10) && i)
        {
            printf("\n");
        }
        printf("0x%02x", buffer[i]);
        i++;
    }
    printf("\n");
}

/**
 * main - check the code for Holberton School students.
 *
 * Return: Always 0.
 */
int main(void)
{
    char *a;

    a = _calloc(98, sizeof(char));
    strcpy(a, "Holberton");
    strcpy(a + 9, " School! :)\n");
    a[97] = '!';
    simple_print_buffer(a, 98);
    free(a);
    return (0);
}
julien@ubuntu:~/0x0b. more malloc, free$ gcc -Wall -pedantic -Werror -Wextra 2-main.c 2-calloc.c -o c
julien@ubuntu:~/0x0b. more malloc, free$ ./c
0x48 0x6f 0x6c 0x62 0x65 0x72 0x74 0x6f 0x6e 0x20
0x53 0x63 0x68 0x6f 0x6f 0x6c 0x21 0x20 0x3a 0x29
0x0a 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00
0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x21
julien@ubuntu:~/0x0b. more malloc, free$ 

3. array_range

File: 3-array_range.c

Write a function that creates an array of integers.

• Prototype: int *array_range(int min, int max);
• The array created should contain all the values from min (included) to max (included), ordered from min to max
• Return: the pointer to the newly created array
• If min > max, return NULL
• If malloc fails, return NULL

julien@ubuntu:~/0x0b. more malloc, free$ cat 3-main.c
#include "holberton.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/**
 * simple_print_buffer - prints buffer in hexa
 * @buffer: the address of memory to print
 * @size: the size of the memory to print
 *
 * Return: Nothing.
 */
void simple_print_buffer(int *buffer, unsigned int size)
{
    unsigned int i;

    i = 0;
    while (i < size)
    {
        if (i % 10)
        {
            printf(" ");
        }
        if (!(i % 10) && i)
        {
            printf("\n");
        }
        printf("0x%02x", buffer[i]);
        i++;
    }
    printf("\n");
}

/**
 * main - check the code for Holberton School students.
 *
 * Return: Always 0.
 */
int main(void)
{
    int *a;

    a = array_range(0, 10);
    simple_print_buffer(a, 11);
    free(a);
    return (0);
}
julien@ubuntu:~/0x0b. more malloc, free$ gcc -Wall -pedantic -Werror -Wextra 3-main.c 3-array_range.c -o d
julien@ubuntu:~/0x0b. more malloc, free$ ./d 
0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09
0x0a
julien@ubuntu:~/0x0b. more malloc, free$