blob: bacfd35c515656cb5afd089df6ca8ced8bd8ff95 [file] [log] [blame]
/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
* stdlib function definitions for NOLIBC
* Copyright (C) 2017-2021 Willy Tarreau <w@1wt.eu>
*/
#ifndef _NOLIBC_STDLIB_H
#define _NOLIBC_STDLIB_H
#include "std.h"
#include "arch.h"
#include "types.h"
#include "sys.h"
#include "string.h"
#include <linux/auxvec.h>
struct nolibc_heap {
size_t len;
char user_p[] __attribute__((__aligned__));
};
/* Buffer used to store int-to-ASCII conversions. Will only be implemented if
* any of the related functions is implemented. The area is large enough to
* store "18446744073709551615" or "-9223372036854775808" and the final zero.
*/
static __attribute__((unused)) char itoa_buffer[21];
/*
* As much as possible, please keep functions alphabetically sorted.
*/
/* must be exported, as it's used by libgcc for various divide functions */
__attribute__((weak,unused,noreturn,section(".text.nolibc_abort")))
void abort(void)
{
sys_kill(sys_getpid(), SIGABRT);
for (;;);
}
static __attribute__((unused))
long atol(const char *s)
{
unsigned long ret = 0;
unsigned long d;
int neg = 0;
if (*s == '-') {
neg = 1;
s++;
}
while (1) {
d = (*s++) - '0';
if (d > 9)
break;
ret *= 10;
ret += d;
}
return neg ? -ret : ret;
}
static __attribute__((unused))
int atoi(const char *s)
{
return atol(s);
}
static __attribute__((unused))
void free(void *ptr)
{
struct nolibc_heap *heap;
if (!ptr)
return;
heap = container_of(ptr, struct nolibc_heap, user_p);
munmap(heap, heap->len);
}
/* getenv() tries to find the environment variable named <name> in the
* environment array pointed to by global variable "environ" which must be
* declared as a char **, and must be terminated by a NULL (it is recommended
* to set this variable to the "envp" argument of main()). If the requested
* environment variable exists its value is returned otherwise NULL is
* returned.
*/
static __attribute__((unused))
char *getenv(const char *name)
{
int idx, i;
if (environ) {
for (idx = 0; environ[idx]; idx++) {
for (i = 0; name[i] && name[i] == environ[idx][i];)
i++;
if (!name[i] && environ[idx][i] == '=')
return &environ[idx][i+1];
}
}
return NULL;
}
static __attribute__((unused))
unsigned long getauxval(unsigned long type)
{
const unsigned long *auxv = _auxv;
unsigned long ret;
if (!auxv)
return 0;
while (1) {
if (!auxv[0] && !auxv[1]) {
ret = 0;
break;
}
if (auxv[0] == type) {
ret = auxv[1];
break;
}
auxv += 2;
}
return ret;
}
static __attribute__((unused))
void *malloc(size_t len)
{
struct nolibc_heap *heap;
/* Always allocate memory with size multiple of 4096. */
len = sizeof(*heap) + len;
len = (len + 4095UL) & -4096UL;
heap = mmap(NULL, len, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE,
-1, 0);
if (__builtin_expect(heap == MAP_FAILED, 0))
return NULL;
heap->len = len;
return heap->user_p;
}
static __attribute__((unused))
void *calloc(size_t size, size_t nmemb)
{
size_t x = size * nmemb;
if (__builtin_expect(size && ((x / size) != nmemb), 0)) {
SET_ERRNO(ENOMEM);
return NULL;
}
/*
* No need to zero the heap, the MAP_ANONYMOUS in malloc()
* already does it.
*/
return malloc(x);
}
static __attribute__((unused))
void *realloc(void *old_ptr, size_t new_size)
{
struct nolibc_heap *heap;
size_t user_p_len;
void *ret;
if (!old_ptr)
return malloc(new_size);
heap = container_of(old_ptr, struct nolibc_heap, user_p);
user_p_len = heap->len - sizeof(*heap);
/*
* Don't realloc() if @user_p_len >= @new_size, this block of
* memory is still enough to handle the @new_size. Just return
* the same pointer.
*/
if (user_p_len >= new_size)
return old_ptr;
ret = malloc(new_size);
if (__builtin_expect(!ret, 0))
return NULL;
memcpy(ret, heap->user_p, heap->len);
munmap(heap, heap->len);
return ret;
}
/* Converts the unsigned long integer <in> to its hex representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (17 bytes for "ffffffffffffffff" or 9 for "ffffffff"). The
* buffer is filled from the first byte, and the number of characters emitted
* (not counting the trailing zero) is returned. The function is constructed
* in a way to optimize the code size and avoid any divide that could add a
* dependency on large external functions.
*/
static __attribute__((unused))
int utoh_r(unsigned long in, char *buffer)
{
signed char pos = (~0UL > 0xfffffffful) ? 60 : 28;
int digits = 0;
int dig;
do {
dig = in >> pos;
in -= (uint64_t)dig << pos;
pos -= 4;
if (dig || digits || pos < 0) {
if (dig > 9)
dig += 'a' - '0' - 10;
buffer[digits++] = '0' + dig;
}
} while (pos >= 0);
buffer[digits] = 0;
return digits;
}
/* converts unsigned long <in> to an hex string using the static itoa_buffer
* and returns the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *utoh(unsigned long in)
{
utoh_r(in, itoa_buffer);
return itoa_buffer;
}
/* Converts the unsigned long integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for 18446744073709551615 in 64-bit, 11 for
* 4294967295 in 32-bit). The buffer is filled from the first byte, and the
* number of characters emitted (not counting the trailing zero) is returned.
* The function is constructed in a way to optimize the code size and avoid
* any divide that could add a dependency on large external functions.
*/
static __attribute__((unused))
int utoa_r(unsigned long in, char *buffer)
{
unsigned long lim;
int digits = 0;
int pos = (~0UL > 0xfffffffful) ? 19 : 9;
int dig;
do {
for (dig = 0, lim = 1; dig < pos; dig++)
lim *= 10;
if (digits || in >= lim || !pos) {
for (dig = 0; in >= lim; dig++)
in -= lim;
buffer[digits++] = '0' + dig;
}
} while (pos--);
buffer[digits] = 0;
return digits;
}
/* Converts the signed long integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for -9223372036854775808 in 64-bit, 12 for
* -2147483648 in 32-bit). The buffer is filled from the first byte, and the
* number of characters emitted (not counting the trailing zero) is returned.
*/
static __attribute__((unused))
int itoa_r(long in, char *buffer)
{
char *ptr = buffer;
int len = 0;
if (in < 0) {
in = -in;
*(ptr++) = '-';
len++;
}
len += utoa_r(in, ptr);
return len;
}
/* for historical compatibility, same as above but returns the pointer to the
* buffer.
*/
static __inline__ __attribute__((unused))
char *ltoa_r(long in, char *buffer)
{
itoa_r(in, buffer);
return buffer;
}
/* converts long integer <in> to a string using the static itoa_buffer and
* returns the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *itoa(long in)
{
itoa_r(in, itoa_buffer);
return itoa_buffer;
}
/* converts long integer <in> to a string using the static itoa_buffer and
* returns the pointer to that string. Same as above, for compatibility.
*/
static __inline__ __attribute__((unused))
char *ltoa(long in)
{
itoa_r(in, itoa_buffer);
return itoa_buffer;
}
/* converts unsigned long integer <in> to a string using the static itoa_buffer
* and returns the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *utoa(unsigned long in)
{
utoa_r(in, itoa_buffer);
return itoa_buffer;
}
/* Converts the unsigned 64-bit integer <in> to its hex representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (17 bytes for "ffffffffffffffff"). The buffer is filled from
* the first byte, and the number of characters emitted (not counting the
* trailing zero) is returned. The function is constructed in a way to optimize
* the code size and avoid any divide that could add a dependency on large
* external functions.
*/
static __attribute__((unused))
int u64toh_r(uint64_t in, char *buffer)
{
signed char pos = 60;
int digits = 0;
int dig;
do {
if (sizeof(long) >= 8) {
dig = (in >> pos) & 0xF;
} else {
/* 32-bit platforms: avoid a 64-bit shift */
uint32_t d = (pos >= 32) ? (in >> 32) : in;
dig = (d >> (pos & 31)) & 0xF;
}
if (dig > 9)
dig += 'a' - '0' - 10;
pos -= 4;
if (dig || digits || pos < 0)
buffer[digits++] = '0' + dig;
} while (pos >= 0);
buffer[digits] = 0;
return digits;
}
/* converts uint64_t <in> to an hex string using the static itoa_buffer and
* returns the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *u64toh(uint64_t in)
{
u64toh_r(in, itoa_buffer);
return itoa_buffer;
}
/* Converts the unsigned 64-bit integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for 18446744073709551615). The buffer is filled from
* the first byte, and the number of characters emitted (not counting the
* trailing zero) is returned. The function is constructed in a way to optimize
* the code size and avoid any divide that could add a dependency on large
* external functions.
*/
static __attribute__((unused))
int u64toa_r(uint64_t in, char *buffer)
{
unsigned long long lim;
int digits = 0;
int pos = 19; /* start with the highest possible digit */
int dig;
do {
for (dig = 0, lim = 1; dig < pos; dig++)
lim *= 10;
if (digits || in >= lim || !pos) {
for (dig = 0; in >= lim; dig++)
in -= lim;
buffer[digits++] = '0' + dig;
}
} while (pos--);
buffer[digits] = 0;
return digits;
}
/* Converts the signed 64-bit integer <in> to its string representation into
* buffer <buffer>, which must be long enough to store the number and the
* trailing zero (21 bytes for -9223372036854775808). The buffer is filled from
* the first byte, and the number of characters emitted (not counting the
* trailing zero) is returned.
*/
static __attribute__((unused))
int i64toa_r(int64_t in, char *buffer)
{
char *ptr = buffer;
int len = 0;
if (in < 0) {
in = -in;
*(ptr++) = '-';
len++;
}
len += u64toa_r(in, ptr);
return len;
}
/* converts int64_t <in> to a string using the static itoa_buffer and returns
* the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *i64toa(int64_t in)
{
i64toa_r(in, itoa_buffer);
return itoa_buffer;
}
/* converts uint64_t <in> to a string using the static itoa_buffer and returns
* the pointer to that string.
*/
static __inline__ __attribute__((unused))
char *u64toa(uint64_t in)
{
u64toa_r(in, itoa_buffer);
return itoa_buffer;
}
/* make sure to include all global symbols */
#include "nolibc.h"
#endif /* _NOLIBC_STDLIB_H */