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#include "ext2/ex_cache.h"
#include "ext2/ext2.h"
#include <assert.h>
#include <camellia/flags.h>
#include <camellia/fs/dir.h>
#include <camellia/fs/misc.h>
#include <camellia/fsutil.h>
#include <camellia/syscalls.h>
#include <err.h>
#include <errno.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
struct handle {
uint32_t n;
bool dir;
};
static int my_read(void *fp, void *buf, size_t len, size_t off);
static int my_write(void *fp, const void *buf, size_t len, size_t off);
static void do_open(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf);
static void do_read(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf, size_t buflen);
static void do_write(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf);
static void do_getsize(struct ext2 *fs, hid_t reqh, struct ufs_request *req);
static int
my_read(void *fp, void *buf, size_t len, size_t off)
{
if (fseek(fp, off, SEEK_SET) < 0) {
return -1;
} else if (fread(buf, len, 1, fp) == 1) {
return 0;
} else {
return -1;
}
}
static int
my_write(void *fp, const void *buf, size_t len, size_t off)
{
if (fseek(fp, off, SEEK_SET) < 0) {
return -1;
} else if (fwrite(buf, len, 1, fp) == 1) {
return 0;
} else {
return -1;
}
}
static void
do_open(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf)
{
bool is_dir = req->len == 0 || buf[req->len-1] == '/';
uint32_t n = ext2c_walk(fs, buf, req->len);
if (n == 0) {
if (is_dir) {
_sys_fs_respond(reqh, NULL, -ENOSYS, 0);
return;
}
/* buf[0] == '/', strrchr != NULL */
char *name = strrchr(buf, '/') + 1;
uint32_t dir_n = ext2c_walk(fs, buf, name - buf);
if (dir_n == 0) {
_sys_fs_respond(reqh, NULL, -ENOENT, 0);
return;
}
n = ext2_alloc_inode(fs, 0100700);
if (n == 0) {
_sys_fs_respond(reqh, NULL, -1, 0);
return;
}
if (ext2_link(fs, dir_n, name, n, 1) < 0) {
_sys_fs_respond(reqh, NULL, -1, 0);
return;
}
} else {
struct ext2d_inode *inode = ext2_req_inode(fs, n);
if (!inode) {
_sys_fs_respond(reqh, NULL, -ENOENT, 0);
return;
}
int type = (inode->perms >> 12) & 0xF;
ext2_dropreq(fs, inode, false);
if ((type == 0x8 && is_dir) || (type == 0x4 && !is_dir)) {
_sys_fs_respond(reqh, NULL, -ENOENT, 0);
return;
} else if (type != 0x8 && type != 0x4) {
_sys_fs_respond(reqh, NULL, -ENOSYS, 0);
return;
}
}
struct handle *h = malloc(sizeof *h);
if (!h) {
_sys_fs_respond(reqh, NULL, -1, 0);
return;
}
h->n = n;
h->dir = is_dir;
_sys_fs_respond(reqh, h, 0, 0);
}
static void
do_read(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf, size_t buflen)
{
struct handle *h = req->id;
if (!h->dir) {
struct ext2d_inode *inode = ext2_req_inode(fs, h->n);
if (!inode) goto err;
fs_normslice(&req->offset, &req->capacity, inode->size_lower, false);
ext2_dropreq(fs, inode, false);
void *b = ext2_req_file(fs, h->n, &req->capacity, req->offset);
if (b) {
_sys_fs_respond(reqh, b, req->capacity, 0);
ext2_dropreq(fs, b, false);
} else if (req->capacity == 0) {
/* set by ext2_req_file on EOF */
_sys_fs_respond(reqh, b, 0, 0);
} else goto err;
} else {
struct dirbuild db;
char namebuf[257];
if (req->capacity > buflen)
req->capacity = buflen;
dir_start(&db, req->offset, buf, buflen);
for (struct ext2_diriter iter = {0}; ext2_diriter(&iter, fs, h->n); ) {
if (iter.ent->namelen_lower == 1 && iter.ent->name[0] == '.') {
continue;
}
if (iter.ent->namelen_lower == 2
&& iter.ent->name[0] == '.'
&& iter.ent->name[1] == '.')
{
continue;
}
if (iter.ent->type == 2) { /* dir */
memcpy(namebuf, iter.ent->name, iter.ent->namelen_lower);
namebuf[iter.ent->namelen_lower] = '/';
dir_appendl(&db, namebuf, iter.ent->namelen_lower + 1);
} else {
dir_appendl(&db, iter.ent->name, iter.ent->namelen_lower);
}
}
_sys_fs_respond(reqh, buf, dir_finish(&db), 0);
}
return;
err:
_sys_fs_respond(reqh, NULL, -1, 0);
}
static void
do_write(struct ext2 *fs, hid_t reqh, struct ufs_request *req, char *buf)
{
struct handle *h = req->id;
if (h->dir) goto err;
struct ext2d_inode *inode = ext2_req_inode(fs, h->n);
if (!inode) goto err;
fs_normslice(&req->offset, &req->len, inode->size_lower, true);
if ((req->flags & WRITE_TRUNCATE) || inode->size_lower < req->offset + req->len) {
inode->size_lower = req->offset + req->len;
if (ext2_dropreq(fs, inode, true) < 0) {
goto err;
}
} else {
ext2_dropreq(fs, inode, false);
}
inode = NULL;
int ret = ext2_write(fs, h->n, buf, req->len, req->offset);
_sys_fs_respond(reqh, NULL, ret, 0);
return;
err:
_sys_fs_respond(reqh, NULL, -1, 0);
}
static void
do_getsize(struct ext2 *fs, hid_t reqh, struct ufs_request *req) {
struct handle *h = req->id;
if (h->dir) goto err;
struct ext2d_inode *inode = ext2_req_inode(fs, h->n);
if (!inode) goto err;
_sys_fs_respond(reqh, NULL, inode->size_lower, 0);
ext2_dropreq(fs, inode, false);
return;
err:
_sys_fs_respond(reqh, NULL, -1, 0);
}
int
main(int argc, char **argv)
{
intr_set(NULL);
if (argc < 2) errx(1, "bad usage");
// TODO pread/pwrite for normal handles
FILE *disk = fopen(argv[1], "r+");
if (!disk) err(1, "couldn't open '%s'", argv[1]);
struct e2device *dev = exc_init(my_read, my_write, (void*)disk);
if (!dev) errx(1, "exc_init failed");
struct ext2 *fs = ext2_opendev(dev, exc_req, exc_drop);
if (!fs) errx(1, "ext2_opendev failed");
const size_t buflen = 4096;
char *buf = malloc(buflen);
struct ufs_request req;
for (;;) {
hid_t reqh = ufs_wait(buf, buflen, &req);
struct handle *h = req.id;
if (reqh < 0) break;
switch (req.op) {
case VFSOP_OPEN:
do_open(fs, reqh, &req, buf);
break;
case VFSOP_READ:
do_read(fs, reqh, &req, buf, buflen);
break;
case VFSOP_WRITE:
do_write(fs, reqh, &req, buf);
break;
case VFSOP_GETSIZE:
do_getsize(fs, reqh, &req);
break;
case VFSOP_CLOSE:
free(h);
_sys_fs_respond(reqh, NULL, -1, 0);
break;
default:
_sys_fs_respond(reqh, NULL, -1, 0);
break;
}
}
warnx("cleaning up");
return 1;
}
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