toaruos/kernel/sys/system.c

404 lines
6.2 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
*
* System Functions
*
* Part of the ToAru OS Kernel
* (C) 2011 Kevin Lange
* Released under the terms of the NCSA License, see the included
* README file for further information.
*/
#include <system.h>
unsigned int __irq_sem = 0;
void spin_lock(uint8_t volatile * lock) {
while(__sync_lock_test_and_set(lock, 0x01)) {
switch_task(1);
}
}
void spin_unlock(uint8_t volatile * lock) {
__sync_lock_release(lock);
}
/*
* memcpy
* Copy from source to destination. Assumes that
* source and destination are not overlapping.
*/
void *
memcpy(
void * restrict dest,
const void * restrict src,
size_t count
) {
asm volatile ("cld; rep movsb" : "+c" (count), "+S" (src), "+D" (dest) :: "memory");
return dest;
}
int
max(int a, int b) {
return (a > b) ? a : b;
}
int
min(int a, int b) {
return (a > b) ? b : a;
}
int
abs(int a) {
return (a >= 0) ? a : -a;
}
void
swap(int *a, int *b) {
int t = *a;
*a = *b;
*b = t;
}
void *
memmove(
void * restrict dest,
const void * restrict src,
size_t count
) {
size_t i;
unsigned char *a = dest;
const unsigned char *b = src;
if (src < dest) {
for ( i = count; i > 0; --i) {
a[i-1] = b[i-1];
}
} else {
for ( i = 0; i < count; ++i) {
a[i] = b[i];
}
}
return dest;
}
int
strcmp(
const char * a,
const char * b
) {
uint32_t i = 0;
while (1) {
if (a[i] < b[i]) {
return -1;
} else if (a[i] > b[i]) {
return 1;
} else {
if (a[i] == '\0') {
return 0;
}
++i;
}
}
}
/*
* memset
* Set `count` bytes to `val`.
*/
void *
memset(
void *b,
int val,
size_t count
) {
asm volatile ("cld; rep stosb" : "+c" (count), "+D" (b) : "a" (val) : "memory");
return b;
}
/*
* memsetw
* Set `count` shorts to `val`.
*/
unsigned short *
memsetw(
unsigned short *dest,
unsigned short val,
int count
) {
int i;
i = 0;
for ( ; i < count; ++i ) {
dest[i] = val;
}
return dest;
}
/*
* strlen
* Returns the length of a given `str`.
*/
uint32_t
strlen(
const char *str
) {
int i = 0;
while (str[i] != (char)0) {
++i;
}
return i;
}
uint32_t __attribute__ ((pure)) krand() {
static uint32_t x = 123456789;
static uint32_t y = 362436069;
static uint32_t z = 521288629;
static uint32_t w = 88675123;
uint32_t t;
t = x ^ (x << 11);
x = y; y = z; z = w;
return w = w ^ (w >> 19) ^ t ^ (t >> 8);
}
/*
* atoi
* Naïve implementation thereof.
*/
int
atoi(
const char *str
) {
uint32_t len = strlen(str);
uint32_t out = 0;
uint32_t i;
uint32_t pow = 1;
for (i = len; i > 0; --i) {
out += (str[i-1] - 48) * pow;
pow *= 10;
}
return out;
}
unsigned short
inports(
unsigned short _port
) {
unsigned short rv;
asm volatile ("inw %1, %0" : "=a" (rv) : "dN" (_port));
return rv;
}
void
outports(
unsigned short _port,
unsigned short _data
) {
asm volatile ("outw %1, %0" : : "dN" (_port), "a" (_data));
}
unsigned int
inportl(
unsigned short _port
) {
unsigned short rv;
asm volatile ("inl %%dx, %%eax" : "=a" (rv) : "dN" (_port));
return rv;
}
void
outportl(
unsigned short _port,
unsigned int _data
) {
asm volatile ("outl %%eax, %%dx" : : "dN" (_port), "a" (_data));
}
/*
* inportb
* Read from an I/O port.
*/
unsigned char
inportb(
unsigned short _port
) {
unsigned char rv;
asm volatile ("inb %1, %0" : "=a" (rv) : "dN" (_port));
return rv;
}
/*
* outportb
* Write to an I/O port.
*/
void
outportb(
unsigned short _port,
unsigned char _data
) {
asm volatile ("outb %1, %0" : : "dN" (_port), "a" (_data));
}
/*
* Output multiple sets of shorts
*/
void outportsm(
unsigned short port,
unsigned char * data,
unsigned long size
) {
asm volatile ("rep outsw" : "+S" (data), "+c" (size) : "d" (port));
}
/*
* Input multiple sets of shorts
*/
void inportsm(
unsigned short port,
unsigned char * data,
unsigned long size
) {
asm volatile ("rep insw" : "+D" (data), "+c" (size) : "d" (port) : "memory");
}
char *
strtok_r(
char * str,
const char * delim,
char ** saveptr
) {
char * token;
if (str == NULL) {
str = *saveptr;
}
str += strspn(str, delim);
if (*str == '\0') {
*saveptr = str;
return NULL;
}
token = str;
str = strpbrk(token, delim);
if (str == NULL) {
*saveptr = (char *)lfind(token, '\0');
} else {
*str = '\0';
*saveptr = str + 1;
}
return token;
}
size_t
lfind(
const char * str,
const char accept
) {
size_t i = 0;
while ( str[i] != accept) {
i++;
}
return (size_t)(str) + i;
}
size_t
rfind(
const char * str,
const char accept
) {
size_t i = strlen(str) - 1;
while (str[i] != accept) {
if (i == 0) return UINT32_MAX;
i--;
}
return (size_t)(str) + i;
}
char *
strstr(const char * haystack, const char * needle) {
const char * out = NULL;
const char * ptr;
const char * acc;
const char * p;
size_t s = strlen(needle);
for (ptr = haystack; *ptr != '\0'; ++ptr) {
size_t accept = 0;
out = ptr;
p = ptr;
for (acc = needle; (*acc != '\0') && (*p != '\0'); ++acc) {
if (*p == *acc) {
accept++;
p++;
} else {
break;
}
}
if (accept == s) {
return (char *)out;
}
}
return NULL;
}
uint8_t startswith(const char * str, const char * accept) {
size_t s = strlen(accept);
for (size_t i = 0; i < s; ++i) {
if (*str != *accept) return 0;
str++;
accept++;
}
return 1;
}
size_t
strspn(
const char * str,
const char * accept
) {
const char * ptr;
const char * acc;
size_t size = 0;
for (ptr = str; *ptr != '\0'; ++ptr) {
for (acc = accept; *acc != '\0'; ++acc) {
if (*ptr == *acc) {
break;
}
}
if (*acc == '\0') {
return size;
} else {
++size;
}
}
return size;
}
char *
strpbrk(
const char * str,
const char * accept
) {
while (*str != '\0') {
const char *acc = accept;
while (*acc != '\0') {
if (*acc++ == *str) {
return (char *) str;
}
}
++str;
}
return NULL;
}
void
real_mode_int(int num, struct regs * r) {
/* Give non-kernel access to the first 1MB of RAM */
for (uintptr_t i = 0; i < 0x00100000; i += 0x1000) {
alloc_frame(get_page(i, 1, kernel_directory), 0, 1);
}
/* Reset protection on first 1MB of RAM when we're done */
for (uintptr_t i = 0; i < 0x00100000; i += 0x1000) {
alloc_frame(get_page(i, 1, kernel_directory), 1, 0);
}
}