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#include <pland/syscall.h>
#include <knob/format.h>
#include <knob/heap.h>
#include <knob/env.h>
struct ofl_node {
struct ofl_node *next;
struct ofl_node *prev;
_file_handle_t handle;
};
static struct ofl_node *head_ofl_node = 0;
void _close_all_files() {
for (struct ofl_node *i = head_ofl_node; i; i = i->next)
_close_file(i->handle);
}
struct file {
struct ofl_node *node;
_file_handle_t handle;
uint32_t position;
uint32_t length;
};
const char *remove_prefix(const char *path, uint8_t *dn_out) {
if ((path[0] != 's') || (path[1] != 'd'))
goto no_prefix;
const char *num_part = path + 2;
for (uint32_t i = 0; num_part[i]; ++i)
if (num_part[i] == ':') {
uint32_t dn_large;
if (!try_sntoi(num_part, i, &dn_large) || dn_large > 255)
goto no_prefix;
*dn_out = (uint8_t)dn_large;
return num_part + i + 1;
}
no_prefix:
*dn_out = current_drive;
return path;
}
struct file *open_file(const char *path) {
uint8_t dn;
path = remove_prefix(path, &dn);
_file_handle_t h = _open_file(dn, path);
if (!h)
return 0;
struct ofl_node *new_node = get_block(sizeof(struct ofl_node));
new_node->next = head_ofl_node;
new_node->prev = 0;
new_node->handle = h;
if (head_ofl_node)
head_ofl_node->prev = new_node;
head_ofl_node = new_node;
struct file *f = get_block(sizeof(struct file));
f->node = new_node;
f->handle = h;
f->position = 0;
f->length = _file_size(h);
return f;
}
void close_file(struct file *f) {
_close_file(f->handle);
struct ofl_node *n = f->node;
if (n->next)
n->next->prev = n->prev;
if (n->prev)
n->prev->next = n->next;
if (n == head_ofl_node)
head_ofl_node = n->next;
free_block(n);
free_block(f);
}
uint32_t read_from_file(struct file *f, uint32_t max, void *buf) {
if (f->position + max > f->length)
max = f->length - f->position;
uint32_t read = _file_read(f->handle, f->position, max, buf);
f->position += read;
return read;
}
//return value and max_length don't include null terminator
uint32_t read_line_from_file(struct file *f, char *sz, uint32_t max_length) {
uint8_t i;
for (i = 0; i < max_length; ++i) {
char byte;
if (!read_from_file(f, 1, &byte) || (byte == '\n'))
break;
sz[i] = byte;
}
sz[i] = '\0';
return i;
}
uint32_t seek_file_to(struct file *f, uint32_t to) {
if (to > f->length)
to = f->length;
return f->position = to;
}
int32_t seek_file_by(struct file *f, int32_t by) {
uint32_t old = f->position;
uint32_t to = old + by > f->length ? f->length : old + by;
f->position = to;
return to - old;
}
__attribute__ ((pure))
uint32_t file_size(struct file *f) {
return f->length;
}
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