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#include <stdbool.h>
#include <stdint.h>
#include "drive.h"
void memcpy(void *to, const void *from, uint32_t n) {
uint32_t *tp = to;
const uint32_t *fp = from;
while (n >= 4) {
*(tp++) = *(fp++);
n -= 4;
}
uint8_t *tpp = (uint8_t *)tp, *fpp = (uint8_t *)fp;
while (n--)
*(tpp++) = *(fpp++);
}
void fmcpy(void *to, const struct drive *d, file_id_t f, uint32_t from, uint32_t n) {
uint8_t buf[512];
d->load_sector(d, f, from >> 9, buf);
uint16_t from_low = from & 511;
if (!((from_low + n) & ~511)) {
memcpy(to, buf + from_low, n);
return;
}
uint32_t i = 512 - from_low;
memcpy(to, buf + from_low, i);
n -= i;
uint32_t fsi = (from + i) >> 9;
while (n & ~511) {
d->load_sector(d, f, fsi, buf);
memcpy(to + i, buf, 512);
i += 512;
n -= 512;
++fsi;
}
d->load_sector(d, f, fsi, buf);
memcpy(to + i, buf, n);
}
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