/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <AK/Assertions.h>
#include <AK/HashMap.h>
#include <AK/Noncopyable.h>
#include <AK/StdLibExtras.h>
#include <AK/Types.h>
#include <AK/Utf8View.h>
#include <Kernel/Syscall.h>
#include <alloca.h>
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
static void strtons(const char* str, char** endptr)
{
assert(endptr);
char* ptr = const_cast<char*>(str);
while (isspace(*ptr)) {
ptr += 1;
}
*endptr = ptr;
}
enum Sign {
Negative,
Positive,
};
static Sign strtosign(const char* str, char** endptr)
{
assert(endptr);
if (*str == '+') {
*endptr = const_cast<char*>(str + 1);
return Sign::Positive;
} else if (*str == '-') {
*endptr = const_cast<char*>(str + 1);
return Sign::Negative;
} else {
*endptr = const_cast<char*>(str);
return Sign::Positive;
}
}
enum DigitConsumeDecision {
Consumed,
PosOverflow,
NegOverflow,
Invalid,
};
template<typename T, T min_value, T max_value>
class NumParser {
AK_MAKE_NONMOVABLE(NumParser)
public:
NumParser(Sign sign, int base)
: m_base(base)
, m_num(0)
, m_sign(sign)
{
m_cutoff = positive() ? (max_value / base) : (min_value / base);
m_max_digit_after_cutoff = positive() ? (max_value % base) : (min_value % base);
}
int parse_digit(char ch)
{
int digit;
if (isdigit(ch))
digit = ch - '0';
else if (islower(ch))
digit = ch - ('a' - 10);
else if (isupper(ch))
digit = ch - ('A' - 10);
else
return -1;
if (static_cast<T>(digit) >= m_base)
return -1;
return digit;
}
DigitConsumeDecision consume(char ch)
{
int digit = parse_digit(ch);
if (digit == -1)
return DigitConsumeDecision::Invalid;
if (!can_append_digit(digit)) {
if (m_sign != Sign::Negative) {
return DigitConsumeDecision::PosOverflow;
} else {
return DigitConsumeDecision::NegOverflow;
}
}
m_num *= m_base;
m_num += positive() ? digit : -digit;
return DigitConsumeDecision::Consumed;
}
T number() const { return m_num; };
private:
bool can_append_digit(int digit)
{
const bool is_below_cutoff = positive() ? (m_num < m_cutoff) : (m_num > m_cutoff);
if (is_below_cutoff) {
return true;
} else {
return m_num == m_cutoff && digit < m_max_digit_after_cutoff;
}
}
bool positive() const
{
return m_sign != Sign::Negative;
}
const T m_base;
T m_num;
T m_cutoff;
int m_max_digit_after_cutoff;
Sign m_sign;
};
typedef NumParser<int, INT_MIN, INT_MAX> IntParser;
typedef NumParser<long long, LONG_LONG_MIN, LONG_LONG_MAX> LongLongParser;
typedef NumParser<unsigned long long, 0ULL, ULONG_LONG_MAX> ULongLongParser;
static bool is_either(char* str, int offset, char lower, char upper)
{
char ch = *(str + offset);
return ch == lower || ch == upper;
}
__attribute__((warn_unused_result)) int __generate_unique_filename(char* pattern)
{
size_t length = strlen(pattern);
if (length < 6 || memcmp(pattern + length - 6, "XXXXXX", 6)) {
errno = EINVAL;
return -1;
}
size_t start = length - 6;
static constexpr char random_characters[] = "abcdefghijklmnopqrstuvwxyz0123456789";
for (int attempt = 0; attempt < 100; ++attempt) {
for (int i = 0; i < 6; ++i)
pattern[start + i] = random_characters[(rand() % sizeof(random_characters))];
struct stat st;
int rc = lstat(pattern, &st);
if (rc < 0 && errno == ENOENT)
return 0;
}
errno = EEXIST;
return -1;
}
extern "C" {
// Itanium C++ ABI methods defined in crt0.cpp
extern int __cxa_atexit(void (*function)(void*), void* paramter, void* dso_handle);
extern void __cxa_finalize(void* dso_handle);
void exit(int status)
{
__cxa_finalize(nullptr);
extern void _fini();
_fini();
fflush(stdout);
fflush(stderr);
_exit(status);
}
static void __atexit_to_cxa_atexit(void* handler)
{
reinterpret_cast<void (*)()>(handler)();
}
int atexit(void (*handler)())
{
return __cxa_atexit(__atexit_to_cxa_atexit, (void*)handler, nullptr);
}
void abort()
{
// For starters, send ourselves a SIGABRT.
raise(SIGABRT);
// If that didn't kill us, try harder.
raise(SIGKILL);
_exit(127);
}
static HashTable<const char*> s_malloced_environment_variables;
static void free_environment_variable_if_needed(const char* var)
{
if (!s_malloced_environment_variables.contains(var))
return;
free(const_cast<char*>(var));
s_malloced_environment_variables.remove(var);
}
char* getenv(const char* name)
{
size_t vl = strlen(name);
for (size_t i = 0; environ[i]; ++i) {
const char* decl = environ[i];
char* eq = strchr(decl, '=');
if (!eq)
continue;
size_t varLength = eq - decl;
if (vl != varLength)
continue;
if (strncmp(decl, name, varLength) == 0) {
return eq + 1;
}
}
return nullptr;
}
int unsetenv(const char* name)
{
auto new_var_len = strlen(name);
size_t environ_size = 0;
int skip = -1;
for (; environ[environ_size]; ++environ_size) {
char* old_var = environ[environ_size];
char* old_eq = strchr(old_var, '=');
ASSERT(old_eq);
size_t old_var_len = old_eq - old_var;
if (new_var_len != old_var_len)
continue; // can't match
if (strncmp(name, old_var, new_var_len) == 0)
skip = environ_size;
}
if (skip == -1)
return 0; // not found: no failure.
// Shuffle the existing array down by one.
memmove(&environ[skip], &environ[skip + 1], ((environ_size - 1) - skip) * sizeof(environ[0]));
environ[environ_size - 1] = nullptr;
free_environment_variable_if_needed(name);
return 0;
}
int setenv(const char* name, const char* value, int overwrite)
{
if (!overwrite && !getenv(name))
return 0;
auto length = strlen(name) + strlen(value) + 2;
auto* var = (char*)malloc(length);
snprintf(var, length, "%s=%s", name, value);
s_malloced_environment_variables.set(var);
return putenv(var);
}
int putenv(char* new_var)
{
char* new_eq = strchr(new_var, '=');
if (!new_eq)
return unsetenv(new_var);
auto new_var_len = new_eq - new_var;
int environ_size = 0;
for (; environ[environ_size]; ++environ_size) {
char* old_var = environ[environ_size];
char* old_eq = strchr(old_var, '=');
ASSERT(old_eq);
auto old_var_len = old_eq - old_var;
if (new_var_len != old_var_len)
continue; // can't match
if (strncmp(new_var, old_var, new_var_len) == 0) {
free_environment_variable_if_needed(old_var);
environ[environ_size] = new_var;
return 0;
}
}
// At this point, we need to append the new var.
// 2 here: one for the new var, one for the sentinel value.
char** new_environ = (char**)malloc((environ_size + 2) * sizeof(char*));
if (new_environ == nullptr) {
errno = ENOMEM;
return -1;
}
for (int i = 0; environ[i]; ++i) {
new_environ[i] = environ[i];
}
new_environ[environ_size] = new_var;
new_environ[environ_size + 1] = nullptr;
// swap new and old
// note that the initial environ is not heap allocated!
extern bool __environ_is_malloced;
if (__environ_is_malloced)
free(environ);
__environ_is_malloced = true;
environ = new_environ;
return 0;
}
double strtod(const char* str, char** endptr)
{
// Parse spaces, sign, and base
char* parse_ptr = const_cast<char*>(str);
strtons(parse_ptr, &parse_ptr);
const Sign sign = strtosign(parse_ptr, &parse_ptr);
// Parse inf/nan, if applicable.
if (is_either(parse_ptr, 0, 'i', 'I')) {
if (is_either(parse_ptr, 1, 'n', 'N')) {
if (is_either(parse_ptr, 2, 'f', 'F')) {
parse_ptr += 3;
if (is_either(parse_ptr, 0, 'i', 'I')) {
if (is_either(parse_ptr, 1, 'n', 'N')) {
if (is_either(parse_ptr, 2, 'i', 'I')) {
if (is_either(parse_ptr, 3, 't', 'T')) {
if (is_either(parse_ptr, 4, 'y', 'Y')) {
parse_ptr += 5;
}
}
}
}
}
if (endptr)
*endptr = parse_ptr;
// Don't set errno to ERANGE here:
// The caller may want to distinguish between "input is
// literal infinity" and "input is not literal infinity
// but did not fit into double".
if (sign != Sign::Negative) {
return __builtin_huge_val();
} else {
return -__builtin_huge_val();
}
}
}
}
if (is_either(parse_ptr, 0, 'n', 'N')) {
if (is_either(parse_ptr, 1, 'a', 'A')) {
if (is_either(parse_ptr, 2, 'n', 'N')) {
if (endptr)
*endptr = parse_ptr + 3;
errno = ERANGE;
if (sign != Sign::Negative) {
return __builtin_nan("");
} else {
return -__builtin_nan("");
}
}
}
}
// Parse base
char exponent_lower;
char exponent_upper;
int base = 10;
if (*parse_ptr == '0') {
const char base_ch = *(parse_ptr + 1);
if (base_ch == 'x' || base_ch == 'X') {
base = 16;
parse_ptr += 2;
}
}
if (base == 10) {
exponent_lower = 'e';
exponent_upper = 'E';
} else {
exponent_lower = 'p';
exponent_upper = 'P';
}
// Parse "digits", possibly keeping track of the exponent offset.
// We parse the most significant digits and the position in the
// base-`base` representation separately. This allows us to handle
// numbers like `0.0000000000000000000000000000000000001234` or
// `1234567890123456789012345678901234567890` with ease.
LongLongParser digits { sign, base };
bool digits_usable = false;
bool should_continue = true;
bool digits_overflow = false;
bool after_decimal = false;
int exponent = 0;
do {
if (!after_decimal && *parse_ptr == '.') {
after_decimal = true;
parse_ptr += 1;
continue;
}
bool is_a_digit;
if (digits_overflow) {
is_a_digit = digits.parse_digit(*parse_ptr) != -1;
} else {
DigitConsumeDecision decision = digits.consume(*parse_ptr);
switch (decision) {
case DigitConsumeDecision::Consumed:
is_a_digit = true;
// The very first actual digit must pass here:
digits_usable = true;
break;
case DigitConsumeDecision::PosOverflow:
// fallthrough
case DigitConsumeDecision::NegOverflow:
is_a_digit = true;
digits_overflow = true;
break;
case DigitConsumeDecision::Invalid:
is_a_digit = false;
break;
default:
ASSERT_NOT_REACHED();
}
}
if (is_a_digit) {
exponent -= after_decimal ? 1 : 0;
exponent += digits_overflow ? 1 : 0;
}
should_continue = is_a_digit;
parse_ptr += should_continue;
} while (should_continue);
if (!digits_usable) {
// No actual number value available.
if (endptr)
*endptr = const_cast<char*>(str);
return 0.0;
}
// Parse exponent.
// We already know the next character is not a digit in the current base,
// nor a valid decimal point. Check whether it's an exponent sign.
if (*parse_ptr == exponent_lower || *parse_ptr == exponent_upper) {
// Need to keep the old parse_ptr around, in case of rollback.
char* old_parse_ptr = parse_ptr;
parse_ptr += 1;
// Can't use atol or strtol here: Must accept excessive exponents,
// even exponents >64 bits.
Sign exponent_sign = strtosign(parse_ptr, &parse_ptr);
IntParser exponent_parser { exponent_sign, base };
bool exponent_usable = false;
bool exponent_overflow = false;
should_continue = true;
do {
bool is_a_digit;
if (exponent_overflow) {
is_a_digit = exponent_parser.parse_digit(*parse_ptr) != -1;
} else {
DigitConsumeDecision decision = exponent_parser.consume(*parse_ptr);
switch (decision) {
case DigitConsumeDecision::Consumed:
is_a_digit = true;
// The very first actual digit must pass here:
exponent_usable = true;
break;
case DigitConsumeDecision::PosOverflow:
// fallthrough
case DigitConsumeDecision::NegOverflow:
is_a_digit = true;
exponent_overflow = true;
break;
case DigitConsumeDecision::Invalid:
is_a_digit = false;
break;
default:
ASSERT_NOT_REACHED();
}
}
should_continue = is_a_digit;
parse_ptr += should_continue;
} while (should_continue);
if (!exponent_usable) {
parse_ptr = old_parse_ptr;
} else if (exponent_overflow) {
// Technically this is wrong. If someone gives us 5GB of digits,
// and then an exponent of -5_000_000_000, the resulting exponent
// should be around 0.
// However, I think it's safe to assume that we never have to deal
// with that many digits anyway.
if (sign != Sign::Negative) {
exponent = INT_MIN;
} else {
exponent = INT_MAX;
}
} else {
// Literal exponent is usable and fits in an int.
// However, `exponent + exponent_parser.number()` might overflow an int.
// This would result in the wrong sign of the exponent!
long long new_exponent = static_cast<long long>(exponent) + static_cast<long long>(exponent_parser.number());
if (new_exponent < INT_MIN) {
exponent = INT_MIN;
} else if (new_exponent > INT_MAX) {
exponent = INT_MAX;
} else {
exponent = static_cast<int>(new_exponent);
}
}
}
// Parsing finished. now we only have to compute the result.
if (endptr)
*endptr = const_cast<char*>(parse_ptr);
// If `digits` is zero, we don't even have to look at `exponent`.
if (digits.number() == 0) {
if (sign != Sign::Negative) {
return 0.0;
} else {
return -0.0;
}
}
// Deal with extreme exponents.
// The smallest normal is 2^-1022.
// The smallest denormal is 2^-1074.
// The largest number in `digits` is 2^63 - 1.
// Therefore, if "base^exponent" is smaller than 2^-(1074+63), the result is 0.0 anyway.
// This threshold is roughly 5.3566 * 10^-343.
// So if the resulting exponent is -344 or lower (closer to -inf),
// the result is 0.0 anyway.
// We only need to avoid false positives, so we can ignore base 16.
if (exponent <= -344) {
errno = ERANGE;
// Definitely can't be represented more precisely.
// I lied, sometimes the result is +0.0, and sometimes -0.0.
if (sign != Sign::Negative) {
return 0.0;
} else {
return -0.0;
}
}
// The largest normal is 2^+1024-eps.
// The smallest number in `digits` is 1.
// Therefore, if "base^exponent" is 2^+1024, the result is INF anyway.
// This threshold is roughly 1.7977 * 10^-308.
// So if the resulting exponent is +309 or higher,
// the result is INF anyway.
// We only need to avoid false positives, so we can ignore base 16.
if (exponent >= 309) {
errno = ERANGE;
// Definitely can't be represented more precisely.
// I lied, sometimes the result is +INF, and sometimes -INF.
if (sign != Sign::Negative) {
return __builtin_huge_val();
} else {
return -__builtin_huge_val();
}
}
// TODO: If `exponent` is large, this could be made faster.
double value = digits.number();
if (exponent < 0) {
exponent = -exponent;
for (int i = 0; i < exponent; ++i) {
value /= base;
}
if (value == -0.0 || value == +0.0) {
errno = ERANGE;
}
} else if (exponent > 0) {
for (int i = 0; i < exponent; ++i) {
value *= base;
}
if (value == -__builtin_huge_val() || value == +__builtin_huge_val()) {
errno = ERANGE;
}
}
return value;
}
long double strtold(const char* str, char** endptr)
{
assert(sizeof(double) == sizeof(long double));
return strtod(str, endptr);
}
float strtof(const char* str, char** endptr)
{
return strtod(str, endptr);
}
double atof(const char* str)
{
return strtod(str, nullptr);
}
int atoi(const char* str)
{
long value = strtol(str, nullptr, 10);
if (value > INT_MAX) {
return INT_MAX;
}
return value;
}
long atol(const char* str)
{
return strtol(str, nullptr, 10);
}
long long atoll(const char* str)
{
return strtoll(str, nullptr, 10);
}
static char ptsname_buf[32];
char* ptsname(int fd)
{
if (ptsname_r(fd, ptsname_buf, sizeof(ptsname_buf)) < 0)
return nullptr;
return ptsname_buf;
}
int ptsname_r(int fd, char* buffer, size_t size)
{
int rc = syscall(SC_ptsname_r, fd, buffer, size);
__RETURN_WITH_ERRNO(rc, rc, -1);
}
static unsigned long s_next_rand = 1;
int rand()
{
s_next_rand = s_next_rand * 1103515245 + 12345;
return ((unsigned)(s_next_rand / ((RAND_MAX + 1) * 2)) % (RAND_MAX + 1));
}
void srand(unsigned seed)
{
s_next_rand = seed;
}
int abs(int i)
{
return i < 0 ? -i : i;
}
long int random()
{
return rand();
}
void srandom(unsigned seed)
{
srand(seed);
}
int system(const char* command)
{
if (!command)
return 1;
auto child = fork();
if (child < 0)
return -1;
if (!child) {
int rc = execl("/bin/sh", "sh", "-c", command, nullptr);
ASSERT(rc < 0);
perror("execl");
exit(127);
}
int wstatus;
waitpid(child, &wstatus, 0);
return WEXITSTATUS(wstatus);
}
char* mktemp(char* pattern)
{
if (__generate_unique_filename(pattern) < 0)
pattern[0] = '\0';
return pattern;
}
int mkstemp(char* pattern)
{
char* path = mktemp(pattern);
int fd = open(path, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); // I'm using the flags I saw glibc using.
if (fd >= 0)
return fd;
return -1;
}
char* mkdtemp(char* pattern)
{
if (__generate_unique_filename(pattern) < 0)
return nullptr;
if (mkdir(pattern, 0700) < 0)
return nullptr;
return pattern;
}
void* bsearch(const void* key, const void* base, size_t nmemb, size_t size, int (*compar)(const void*, const void*))
{
int low = 0;
int high = nmemb - 1;
while (low <= high) {
int middle = (low + high) / 2;
void* middle_memb = const_cast<char*>((const char*)base + middle * size);
int comparison = compar(key, middle_memb);
if (comparison < 0)
high = middle - 1;
else if (comparison > 0)
low = middle + 1;
else
return middle_memb;
}
return NULL;
}
div_t div(int numerator, int denominator)
{
div_t result;
result.quot = numerator / denominator;
result.rem = numerator % denominator;
if (numerator >= 0 && result.rem < 0) {
result.quot++;
result.rem -= denominator;
}
return result;
}
ldiv_t ldiv(long numerator, long denominator)
{
ldiv_t result;
result.quot = numerator / denominator;
result.rem = numerator % denominator;
if (numerator >= 0 && result.rem < 0) {
result.quot++;
result.rem -= denominator;
}
return result;
}
size_t mbstowcs(wchar_t*, const char*, size_t)
{
ASSERT_NOT_REACHED();
}
size_t mbtowc(wchar_t* wch, const char* data, size_t data_size)
{
// FIXME: This needs a real implementation.
UNUSED_PARAM(data_size);
if (wch && data) {
*wch = *data;
return 1;
}
if (!wch && data) {
return 1;
}
return 0;
}
int wctomb(char*, wchar_t)
{
ASSERT_NOT_REACHED();
}
size_t wcstombs(char* dest, const wchar_t* src, size_t max)
{
char* originalDest = dest;
while ((size_t)(dest - originalDest) < max) {
StringView v { (const char*)src, sizeof(wchar_t) };
// FIXME: dependent on locale, for now utf-8 is supported.
Utf8View utf8 { v };
if (*utf8.begin() == '\0') {
*dest = '\0';
return (size_t)(dest - originalDest); // Exclude null character in returned size
}
for (auto byte : utf8) {
if (byte != '\0')
*dest++ = byte;
}
++src;
}
return max;
}
long strtol(const char* str, char** endptr, int base)
{
long long value = strtoll(str, endptr, base);
if (value < LONG_MIN) {
errno = ERANGE;
return LONG_MIN;
} else if (value > LONG_MAX) {
errno = ERANGE;
return LONG_MAX;
}
return value;
}
unsigned long strtoul(const char* str, char** endptr, int base)
{
unsigned long long value = strtoull(str, endptr, base);
if (value > ULONG_MAX) {
errno = ERANGE;
return ULONG_MAX;
}
return value;
}
long long strtoll(const char* str, char** endptr, int base)
{
// Parse spaces and sign
char* parse_ptr = const_cast<char*>(str);
strtons(parse_ptr, &parse_ptr);
const Sign sign = strtosign(parse_ptr, &parse_ptr);
// Parse base
if (base == 0) {
if (*parse_ptr == '0') {
parse_ptr += 1;
if (*parse_ptr == 'x' || *parse_ptr == 'X') {
base = 16;
parse_ptr += 2;
} else {
base = 8;
}
} else {
base = 10;
}
}
// Parse actual digits.
LongLongParser digits { sign, base };
bool digits_usable = false;
bool should_continue = true;
bool overflow = false;
do {
bool is_a_digit;
if (overflow) {
is_a_digit = digits.parse_digit(*parse_ptr) >= 0;
} else {
DigitConsumeDecision decision = digits.consume(*parse_ptr);
switch (decision) {
case DigitConsumeDecision::Consumed:
is_a_digit = true;
// The very first actual digit must pass here:
digits_usable = true;
break;
case DigitConsumeDecision::PosOverflow: // fall-through
case DigitConsumeDecision::NegOverflow:
is_a_digit = true;
overflow = true;
break;
case DigitConsumeDecision::Invalid:
is_a_digit = false;
break;
default:
ASSERT_NOT_REACHED();
}
}
should_continue = is_a_digit;
parse_ptr += should_continue;
} while (should_continue);
if (!digits_usable) {
// No actual number value available.
if (endptr)
*endptr = const_cast<char*>(str);
return 0;
}
if (endptr)
*endptr = parse_ptr;
if (overflow) {
errno = ERANGE;
if (sign != Sign::Negative) {
return LONG_LONG_MAX;
} else {
return LONG_LONG_MIN;
}
}
return digits.number();
}
unsigned long long strtoull(const char* str, char** endptr, int base)
{
// Parse spaces and sign
char* parse_ptr = const_cast<char*>(str);
strtons(parse_ptr, &parse_ptr);
// Parse base
if (base == 0) {
if (*parse_ptr == '0') {
parse_ptr += 1;
if (*parse_ptr == 'x' || *parse_ptr == 'X') {
base = 16;
parse_ptr += 2;
} else {
base = 8;
}
} else {
base = 10;
}
}
// Parse actual digits.
ULongLongParser digits { Sign::Positive, base };
bool digits_usable = false;
bool should_continue = true;
bool overflow = false;
do {
bool is_a_digit;
if (overflow) {
is_a_digit = digits.parse_digit(*parse_ptr) >= 0;
} else {
DigitConsumeDecision decision = digits.consume(*parse_ptr);
switch (decision) {
case DigitConsumeDecision::Consumed:
is_a_digit = true;
// The very first actual digit must pass here:
digits_usable = true;
break;
case DigitConsumeDecision::PosOverflow: // fall-through
case DigitConsumeDecision::NegOverflow:
is_a_digit = true;
overflow = true;
break;
case DigitConsumeDecision::Invalid:
is_a_digit = false;
break;
default:
ASSERT_NOT_REACHED();
}
}
should_continue = is_a_digit;
parse_ptr += should_continue;
} while (should_continue);
if (!digits_usable) {
// No actual number value available.
if (endptr)
*endptr = const_cast<char*>(str);
return 0;
}
if (endptr)
*endptr = parse_ptr;
if (overflow) {
errno = ERANGE;
return LONG_LONG_MAX;
}
return digits.number();
}
// Serenity's PRNG is not cryptographically secure. Do not rely on this for
// any real crypto! These functions (for now) are for compatibility.
// TODO: In the future, rand can be made determinstic and this not.
uint32_t arc4random(void)
{
char buf[4];
syscall(SC_getrandom, buf, 4, 0);
return *(uint32_t*)buf;
}
void arc4random_buf(void* buffer, size_t buffer_size)
{
// arc4random_buf should never fail, but user supplied buffers could fail.
// However, if the user passes a garbage buffer, that's on them.
syscall(SC_getrandom, buffer, buffer_size, 0);
}
uint32_t arc4random_uniform(uint32_t max_bounds)
{
// XXX: Should actually apply special rules for uniformity; avoid what is
// called "modulo bias".
return arc4random() % max_bounds;
}
char* realpath(const char* pathname, char* buffer)
{
if (!pathname) {
errno = EFAULT;
return nullptr;
}
size_t size = PATH_MAX;
if (buffer == nullptr)
buffer = (char*)malloc(size);
Syscall::SC_realpath_params params { { pathname, strlen(pathname) }, { buffer, size } };
int rc = syscall(SC_realpath, ¶ms);
if (rc < 0) {
errno = -rc;
return nullptr;
}
errno = 0;
return buffer;
}
int posix_openpt(int flags)
{
if (flags & ~(O_RDWR | O_NOCTTY | O_CLOEXEC)) {
errno = EINVAL;
return -1;
}
return open("/dev/ptmx", flags);
}
int grantpt(int fd)
{
(void)fd;
return 0;
}
int unlockpt(int fd)
{
(void)fd;
return 0;
}
}