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#ifndef _STDLIB_H
#define _STDLIB_H
#include <stdc_common.h>
#define EXIT_FAILURE (-1)
#define EXIT_SUCCESS 0
#define RAND_MAX 2147483647
// @NONSTANDARD: we don't define MB_CUR_MAX or any of the mbtowc functions
typedef struct {
int quot;
int rem;
} div_t;
typedef struct {
long quot;
long rem;
} ldiv_t;
char *getenv(const char *name) {
int i, j;
for (i = 0; _envp[i]; ++i) {
char *key = _envp[i];
for (j = 0; key[j] != '=' && name[j]; ++j)
if (name[j] != key[j])
break;
if (key[j] == '=' && !name[j])
return key + (j+1);
}
return NULL;
}
double atof(const char *nptr) {
return strtod(nptr, NULL);
}
int atoi(const char *nptr) {
return _clamp_long_to_int(strtol(nptr, NULL, 10));
}
long atol(const char *nptr) {
return strtol(nptr, NULL, 10);
}
int rand(void) {
// https://en.wikipedia.org/wiki/Linear_congruential_generator
// we're using musl/newlib's constants
_rand_seed = 6364136223846793005 * _rand_seed + 1;
return _rand_seed >> 33;
}
void srand(unsigned seed) {
_rand_seed = seed;
}
void *calloc(size_t nmemb, size_t size) {
if (nmemb > 0xffffffffffffffff / size)
return NULL;
// NB: our malloc implementation returns zeroed memory
return malloc(nmemb * size);
}
void *realloc(void *ptr, size_t size) {
if (!ptr) return malloc(size);
if (!size) {
free(ptr);
return NULL;
}
uint64_t *memory = (char *)ptr - 16;
uint64_t old_size = *memory;
uint64_t *new_memory = _mremap(memory, old_size, size, MREMAP_MAYMOVE);
if ((uint64_t)new_memory > 0xffffffffffff0000) return NULL;
*new_memory = size;
return (char *)new_memory + 16;
}
int atexit(void (*func)(void)) {
if (_n_exit_handlers >= 32) return -1;
_exit_handlers[_n_exit_handlers++] = func;
return 0;
}
int system(const char *string) {
if (!string) return 1;
int pid = fork();
if (pid < 0) {
return -1;
} else if (pid == 0) {
// child
char *argv[] = {
"/bin/sh",
"-c",
0,
0
};
argv[2] = string;
execve("/bin/sh", argv, _envp);
// on success, execve does not return.
_Exit(-1);
} else {
// parent
int status = 0;
int ret = wait4(pid, &status, 0, NULL);
if (ret != pid) return -1;
if (_WIFSIGNALED(status)) return -1;
return _WEXITSTATUS(status);
}
}
void *bsearch(const void *key, const void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *)) {
size_t lo = 0;
size_t hi = nmemb;
while (lo < hi) {
size_t mid = (lo + hi) >> 1;
void *elem = (char *)base + mid * size;
int cmp = compar(key, elem);
if (cmp < 0) {
// key < elem
hi = mid;
} else if (cmp) {
// key > elem
lo = mid + 1;
} else {
return elem;
}
}
return NULL;
}
void qsort(void *base, size_t nmemb, size_t size, int (*compar)(const void *, const void *)) {
// quicksort
if (nmemb < 2) return;
void *temp = malloc(size);
void *mid = (char *)base + ((nmemb >> 1) * size); // choose middle element to speed up sorting an already-sorted array
size_t pivot_index = 0, i;
for (i = 0; i < nmemb; ++i) {
void *elem = (char *)base + i * size;
if (compar(elem, mid) < 0)
++pivot_index;
}
void *pivot = (char *)base + pivot_index * size;
memcpy(temp, pivot, size);
memcpy(pivot, mid, size);
memcpy(mid, temp, size);
char *l, *r = (char *)base + (nmemb-1) * size;
for (l = base; l < r;) {
if (compar(l, pivot) > 0) {
// swap l and r
memcpy(temp, l, size);
memcpy(l, r, size);
memcpy(r, temp, size);
r -= size;
} else {
// l is already in the right place
l += size;
}
}
qsort(base, pivot_index, size, compar);
qsort((char *)pivot + size, nmemb - 1 - pivot_index, size, compar);
free(temp);
}
int abs(int x) {
return x >= 0 ? x : -x;
}
long labs(long x) {
return x >= 0 ? x : -x;
}
div_t div(int numer, int denom) {
div_t d;
d.quot = numer / denom;
d.rem = numer % denom;
return d;
}
ldiv_t ldiv(long numer, long denom) {
ldiv_t d;
d.quot = numer / denom;
d.rem = numer % denom;
return d;
}
#endif // _STDLIB_H
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