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#include <drivers/uart.h>
#include <lib/mem.h>
void memshow32(unsigned long* addr, unsigned int n)
{
for(unsigned int i = 0; i < n; i++) {
uart_hex(addr[i]);
if (i+1 != n)
uart_char(0x20);
}
uart_char(0x0a);
}
void memcpy(unsigned char* src, unsigned char* dest, unsigned int n)
{
for(unsigned int i = 0; i < n; i++) {
dest[i] = src[i];
}
}
unsigned char memcmp(unsigned char* a, unsigned char* b, unsigned int n)
{
for(unsigned int i = 0; i < n; i++) {
if (a[i] != b[i])
return 0;
}
return 1;
}
void memcpy32(unsigned long* src, unsigned long* dest, unsigned int n)
{
for(unsigned int i = 0; i < n; i++) {
dest[i] = src[i];
}
}
unsigned char memcmp32(unsigned long* a, unsigned long* b, unsigned int n)
{
for(unsigned int i = 0; i < n; i++) {
if (a[i] != b[i])
return 0;
}
return 1;
}
#define MAX_MM 0x100000
static unsigned char rpi_heap[MAX_MM] = {0,};
static void* rpi_heap_top = &rpi_heap;
void* malloc(unsigned char size)
{
unsigned char* mem = (unsigned char*)rpi_heap;
unsigned long i = 0;
// TODO: Use Null PID
while (((void*)(mem+i) < rpi_heap_top) && !(mem[i] == size && mem[i+1]==0)) {
i += mem[i]+2;
}
// Update top of heap
if (mem[i] == 0)
rpi_heap_top = (void*)&mem[i+2+size];
mem[i] = size;
// Use allocator's PID
mem[i+1] = 1;
return (void*)&mem[i+2];
}
void* malloca(unsigned char size, unsigned char amnt)
{
unsigned char* mem = (unsigned char*)rpi_heap;
unsigned long i = 0;
// TODO: Use Null PID
while(1) {
unsigned long diff = (unsigned long)mem + i + 2;
diff %= amnt;
diff = amnt - diff;
diff %= amnt;
if((mem[i] == size) && mem[i+1]==0) {
if(diff == 0) {
mem[i] = size;
mem[i+1] = 1;
return (void*)&mem[i+2];
}
} else if (mem[i] == 0) {
if(diff == 0 || diff == amnt) {
mem[i] = size;
mem[i+1] = 1;
rpi_heap_top = (void*)&mem[i+2+size];
return (void*)&mem[i+2];
} else {
if(diff <= 2) {
diff += amnt;
}
mem[i] = diff-2;
i += diff;
mem[i] = size;
mem[i+1] = 1;
rpi_heap_top = (void*)&mem[i+2+size];
return (void*)&mem[i+2];
}
}
i += mem[i]+2;
}
}
void free(void* memloc)
{
// Don't try to free memory outside of heap
if(!(((void*)rpi_heap <= memloc) && (memloc < rpi_heap_top)))
return;
unsigned char* base = memloc - 2;
unsigned char size = *base;
// TODO: Use Null PID
base[1] = 0;
// Clear out old memory
for(unsigned int i = 0; i < size; i++) {
base[i+2] = 0;
}
// If it is the last entry, clear it and move the heap top down
if (base + size + 2 == rpi_heap_top) {
base[0] = 0;
rpi_heap_top = base;
}
}
void* heap_base(void)
{
return (void*)rpi_heap;
}
void* heap_top(void)
{
return rpi_heap_top;
}
void heap_info(void)
{
unsigned char* base = rpi_heap;
while ((void*)base < rpi_heap_top) {
unsigned char size = *base;
if(base[1] == 0) {
uart_char('F');
uart_char(' ');
}
uart_hex((unsigned long)(base+2));
uart_string(" Size: ");
uart_10(size);
uart_string("\n");
static char* data = "00 \0";
static unsigned char temp = 0;
for(unsigned int i = 0; i < size; i++) {
temp = (base[2+i]>>4)&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[0] = temp;
temp = (base[2+i])&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[1] = temp;
uart_string(data);
}
uart_char('\n');
base += size + 2;
}
uart_char('\n');
}
void heap_info_u(void)
{
unsigned char* base = rpi_heap;
while ((void*)base < rpi_heap_top) {
unsigned char size = *base;
if(base[1] == 0) {
base += size + 2;
continue;
}
uart_hex((unsigned long)(base+2));
uart_string(" Size: ");
uart_10(size);
uart_string("\n");
static char* data = "00 \0";
static unsigned char temp = 0;
for(unsigned int i = 0; i < size; i++) {
temp = (base[2+i]>>4)&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[0] = temp;
temp = (base[2+i])&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[1] = temp;
uart_string(data);
}
uart_char('\n');
base += size + 2;
}
uart_char('\n');
}
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