Fennix/libc/src/std/lib.c

#include <stdlib.h>
#include <stddef.h>
#include <string.h>

#include "../mem/liballoc_1_1.h"

void abort(void)
{
    __asm__ __volatile__("syscall"
                         :
                         : "a"(0), "D"(-0xAB057)
                         : "rcx", "r11", "memory");

    while (1)
        ;
}

int atexit(void (*function)(void))
{
    return 1;
}

void exit(int status)
{
    _exit(status);
}

int atoi(const char *nptr)
{
    uint64_t Length = strlen((char *)nptr);
    if (nptr)
        while (nptr[Length] != '\0')
            ++Length;
    uint64_t OutBuffer = 0;
    uint64_t Power = 1;
    for (uint64_t i = Length; i > 0; --i)
    {
        OutBuffer += (nptr[i - 1] - 48) * Power;
        Power *= 10;
    }
    return OutBuffer;
}

char **environ = NULL;

char *getenv(const char *name)
{
    char **env = environ;
    if (env == NULL)
        return NULL;
    size_t len = strlen(name);
    while (*env != NULL)
    {
        if ((strncmp(*env, name, len) == 0) && ((*env)[len] == '='))
            return &(*env)[len + 1];
        ++env;
    }
}

void *malloc(size_t Size) { return PREFIX(malloc)(Size); }
void *realloc(void *Address, size_t Size) { return PREFIX(realloc)(Address, Size); }
void *calloc(size_t Count, size_t Size) { return PREFIX(calloc)(Count, Size); }
void free(void *Address)
{
    PREFIX(free)
    (Address);
}

int system(const char *command)
{
    return -1;
}

double atof(const char *nptr)
{
    // FIXME: This is a very bad implementation of atof.
    uint64_t Length = strlen((char *)nptr);
    if (nptr)
        while (nptr[Length] != '\0')
            ++Length;
    double OutBuffer = 0;
    double Power = 1;
    for (uint64_t i = Length; i > 0; --i)
    {
        OutBuffer += (nptr[i - 1] - 48) * Power;
        Power *= 10;
    }
    return OutBuffer;
}