#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

static void
out_of_core(void)
{
    fputs("\nfatal: out of memory\n", stderr);
    exit(2);
}
void *
xmalloc( size_t n )
{
    void *p = malloc( n );
    if( !p )
        out_of_core();
    return p;
}

void *
xrealloc( void *a, size_t n )
{
    void *p = realloc( a, n );
    if( !p )
        out_of_core();
    return p;
}

char *
xstrdup( const char *string )
{
    void *p = xmalloc( strlen(string)+1 );
    strcpy( p, string );
    return p;
}


/**
 * strv_length:
 * @str_array: a %NULL-terminated array of strings
 *
 * Returns the length of the given %NULL-terminated
 * string array @str_array.
 *
 * Return value: length of @str_array.
 *
 */
unsigned int
strv_length (char **str_array)
{
    unsigned int i = 0;

    if (!str_array)
        return 0;

    while (str_array[i])
        ++i;

    return i;
}

/* @brief append a string to a NULL terminated array of strings.
 *
 * @param[inout] array pointer to the NULL terminated list of string pointers.
 * @param[in] string pointer to the string to append to the list.
 * */
void array_append_str(char ***pArray, const char *string)
{
    unsigned int old_len = strv_length(*pArray);
    *pArray = xrealloc(*pArray, sizeof(char**) * (old_len + 2));

    *pArray[old_len] = xstrdup(string);
    *pArray[old_len + 1] = NULL;
}

/* @brief append a string to another string.
 *
 * @param[inout] pDst pointer to the string to be extended.
 * @param[in] appendage pointer to the string to append.
 * */
void str_append_str(char **pDst, const char *appendage)
{
    size_t old_len = strlen(*pDst),
           added_len = strlen(appendage);
    size_t new_len = old_len + added_len + 1;

    if (!appendage)
        return;

    *pDst = (char *)xrealloc(*pDst, sizeof(char) * (new_len));

    strcpy(*pDst + old_len, appendage);

    *pDst[new_len - 1] = '\0';
}

void
strfreev (char **str_array)
{
  if (str_array)
    {
      int i;

      for (i = 0; str_array[i] != NULL; i++)
        free (str_array[i]);

      free (str_array);
    }
}