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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;
// TODO: Put size at end and cleanup from tail
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 + MEM_SIZE_OFFSET] == size && mem[i + MEM_USE_OFFSET]==0)) {
i += mem[i] + MEM_META_SIZE;
}
// Update top of heap
if (mem[i] == 0)
rpi_heap_top = (void*)&mem[i + MEM_META_SIZE + size];
mem[i] = size;
mem[i + MEM_BASE_SIZE + size] = size;
// Use allocator's PID
mem[i + MEM_USE_OFFSET] = 1;
return (void*)&mem[i + MEM_BASE_SIZE];
}
void* malloca(unsigned char size, unsigned char amnt)
{
// Return malloc if alignment size is 0 or 1 - trivial alignment
if(amnt == 0 || amnt == 1)
return malloc(size);
unsigned char* mem = (unsigned char*)rpi_heap;
unsigned long i = 0;
// TODO: Use Null PID
while(1) {
unsigned long diff = (unsigned long)mem + i + MEM_BASE_SIZE;
diff %= amnt;
diff = amnt - diff;
diff %= amnt;
if((mem[i + MEM_SIZE_OFFSET] == size) && mem[i + MEM_USE_OFFSET]==0) {
if(diff == 0) {
mem[i + MEM_SIZE_OFFSET] = size;
mem[i + MEM_BASE_SIZE + size] = size;
mem[i + MEM_USE_OFFSET] = 1;
return (void*)&mem[i + MEM_BASE_SIZE];
}
} else if (mem[i] == 0) {
if(diff == 0) {
mem[i + MEM_SIZE_OFFSET] = size;
mem[i + MEM_BASE_SIZE + size] = size;
mem[i + MEM_USE_OFFSET] = 1;
rpi_heap_top = (void*)&mem[i + MEM_META_SIZE + size];
return (void*)&mem[i + MEM_BASE_SIZE];
} else {
while (diff <= MEM_BASE_SIZE) {
diff += amnt;
}
unsigned long empty_size = diff - MEM_META_SIZE;
mem[i + MEM_SIZE_OFFSET] = empty_size;
mem[i + MEM_BASE_SIZE + empty_size] = empty_size;
i += diff;
mem[i + MEM_SIZE_OFFSET] = size;
mem[i + MEM_BASE_SIZE + size] = size;
mem[i + MEM_USE_OFFSET] = 1;
rpi_heap_top = (void*)&mem[i + MEM_META_SIZE + size];
return (void*)&mem[i + MEM_BASE_SIZE];
}
}
i += mem[i] + MEM_META_SIZE;
}
}
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 - MEM_BASE_SIZE;
unsigned char size = base[MEM_SIZE_OFFSET];
// TODO: Use Null PID
base[MEM_USE_OFFSET] = 0;
// Clear out old memory
for(unsigned int i = 0; i < size; i++) {
base[i + MEM_BASE_SIZE] = 0;
}
// If it is the last entry, clear it and move the heap top down
if (base + size + MEM_META_SIZE == rpi_heap_top) {
while(base[MEM_USE_OFFSET] == 0 && base >= rpi_heap) {
base[MEM_SIZE_OFFSET] = 0;
base[MEM_BASE_SIZE + size] = 0;
rpi_heap_top = base;
unsigned long psize = *(base - 1);
base -= psize + MEM_META_SIZE;
}
}
}
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[MEM_SIZE_OFFSET];
if(base[MEM_USE_OFFSET] == 0) {
uart_char('F');
uart_char(' ');
}
uart_hex((unsigned long)(base + MEM_BASE_SIZE));
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[MEM_BASE_SIZE + i]>>4)&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[0] = temp;
temp = (base[MEM_BASE_SIZE + i])&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[1] = temp;
uart_string(data);
}
uart_char('\n');
base += size + MEM_META_SIZE;
}
uart_char('\n');
}
void heap_info_u(void)
{
unsigned char* base = rpi_heap;
while ((void*)base < rpi_heap_top) {
unsigned char size = base[MEM_SIZE_OFFSET];
if(base[MEM_USE_OFFSET] == 0) {
base += MEM_META_SIZE;
continue;
}
uart_hex((unsigned long)(base + MEM_BASE_SIZE));
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[MEM_BASE_SIZE + i]>>4)&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[0] = temp;
temp = (base[MEM_BASE_SIZE + i])&0xF;
if(temp > 9)
temp += 7;
temp += 0x30;
data[1] = temp;
uart_string(data);
}
uart_char('\n');
base += size + MEM_META_SIZE;
}
uart_char('\n');
}
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