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#include <camellia/flags.h>
#include <camellia/syscalls.h>
#include <shared/mem.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <user/lib/fs/misc.h>
bool fork2_n_mount(const char *path) {
handle_t h;
if (_syscall_fork(FORK_NEWFS, &h) > 0) { /* parent */
_syscall_mount(h, path, strlen(path));
close(h);
return true;
}
return false;
}
void fs_passthru(const char *prefix) {
struct fs_wait_response res;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
int prefix_len = prefix ? strlen(prefix) : 0;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
switch (res.op) {
case VFSOP_OPEN:
if (prefix) {
if (prefix_len + res.len > buf_len) {
_syscall_fs_respond(NULL, -1, 0);
break;
}
// TODO memmove
char tmp[64];
memcpy(tmp, buf, res.len);
memcpy(buf + prefix_len, tmp, res.len);
memcpy(buf, prefix, prefix_len);
res.len += prefix_len;
}
_syscall_fs_respond(NULL, _syscall_open(buf, res.len, res.flags), FSR_DELEGATE);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
void fs_whitelist(const char **list) {
struct fs_wait_response res;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
bool allow;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
switch (res.op) {
case VFSOP_OPEN:
allow = false;
// TODO reverse dir_inject
for (const char **iter = list; *iter; iter++) {
size_t len = strlen(*iter); // inefficient, whatever
if (len <= res.len && !memcmp(buf, *iter, len)) {
allow = true;
break;
}
}
_syscall_fs_respond(NULL, allow ? _syscall_open(buf, res.len, res.flags) : -1, FSR_DELEGATE);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
void fs_dir_inject(const char *path) {
struct fs_dir_handle {
const char *inject;
int delegate, inject_len;
};
const size_t path_len = strlen(path);
struct fs_wait_response res;
struct fs_dir_handle *data;
const size_t buf_len = 1024;
char *buf = malloc(buf_len);
int ret, inject_len;
if (!buf) exit(1);
while (!_syscall_fs_wait(buf, buf_len, &res)) {
data = res.id;
switch (res.op) {
case VFSOP_OPEN:
if (buf[res.len - 1] == '/' &&
res.len < path_len && !memcmp(path, buf, res.len))
{
/* opening a directory that we're injecting into */
data = malloc(sizeof *data);
data->delegate = _syscall_open(buf, res.len, res.flags);
data->inject = path + res.len;
/* inject up to the next slash */
inject_len = 0;
while (data->inject[inject_len] && data->inject[inject_len] != '/')
inject_len++;
if (data->inject[inject_len] == '/')
inject_len++;
data->inject_len = inject_len;
_syscall_fs_respond(data, 0, 0);
} else {
_syscall_fs_respond(NULL, _syscall_open(buf, res.len, res.flags), FSR_DELEGATE);
}
break;
case VFSOP_CLOSE:
if (data->delegate >= 0)
close(data->delegate);
_syscall_fs_respond(NULL, 0, 0);
break;
case VFSOP_READ:
if (res.offset > 0) _syscall_fs_respond(NULL, 0, 0); // TODO working offsets
int out_len = data->inject_len;
memcpy(buf, data->inject, out_len);
buf[out_len++] = '\0';
if (data->delegate >= 0) {
int to_read = res.capacity < buf_len ? res.capacity : buf_len;
to_read -= out_len;
ret = _syscall_read(data->delegate, buf + out_len, to_read, 0);
if (ret > 0) out_len += ret;
// TODO deduplicate entries
}
_syscall_fs_respond(buf, out_len, 0);
break;
case VFSOP_WRITE:
if (data->delegate >= 0)
ret = _syscall_write(data->delegate, buf, res.len, res.offset);
else
ret = -1;
_syscall_fs_respond(NULL, ret, 0);
break;
default:
_syscall_fs_respond(NULL, -1, 0);
break;
}
}
exit(0);
}
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