lib9p/backend/fs.c
Jakub Klama 91ad441d73 Rework code significantly.
- Use vectored I/O everywhere
- Add routines to pretty-print 9P requests
- Improve code style
- Implement clunk request
and so on.
2016-01-28 00:40:43 +01:00

293 lines
6.5 KiB
C

/*
* Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
/*
* Based on libixp code: ©2007-2010 Kris Maglione <maglione.k at Gmail>
*/
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include "../lib9p.h"
#include "../log.h"
static void fs_attach(void *, struct l9p_request *);
static void fs_clunk(void *, struct l9p_request *);
static void fs_create(void *, struct l9p_request *);
static void fs_flush(void *, struct l9p_request *);
static void fs_open(void *, struct l9p_request *);
static void fs_read(void *, struct l9p_request *);
static void fs_remove(void *, struct l9p_request *);
static void fs_stat(void *, struct l9p_request *);
static void fs_walk(void *, struct l9p_request *);
static void fs_write(void *, struct l9p_request *);
static void fs_wstat(void *, struct l9p_request *);
struct fs_softc
{
const char *fs_rootpath;
bool fs_readonly;
};
struct openfile
{
DIR *dir;
int fd;
char *name;
};
static struct openfile *
open_fid(const char *path)
{
struct openfile *ret;
ret = calloc(1, sizeof(*ret));
ret->fd = -1;
ret->name = strdup(path);
return (ret);
}
static void
dostat(struct l9p_stat *s, char *name, struct stat *buf)
{
char *user = getenv("USER");
s->type = 0;
s->dev = 0;
s->qid.type = buf->st_mode&S_IFMT >> 8;
s->qid.path = buf->st_ino;
s->qid.version = 0;
s->mode = buf->st_mode & 0777;
if (S_ISDIR(buf->st_mode)) {
s->mode |= P9_DMDIR;
s->qid.type |= L9P_QTDIR;
}
s->atime = buf->st_atime;
s->mtime = buf->st_mtime;
s->length = buf->st_size;
s->name =name;
s->uid = user;
s->gid = user;
s->muid = user;
}
static void
fs_attach(void *softc, struct l9p_request *req)
{
struct fs_softc *sc = (struct fs_softc *)softc;
req->lr_fid->lo_qid.type = L9P_QTDIR;
req->lr_fid->lo_qid.path = (uintptr_t)req->lr_fid;
req->lr_fid->lo_aux = open_fid(sc->fs_rootpath);
req->lr_resp.rattach.qid = req->lr_fid->lo_qid;
l9p_respond(req, NULL);
}
static void
fs_clunk(void *softc, struct l9p_request *req)
{
struct l9p_connection *conn = req->lr_conn;
struct openfile *file;
struct stat st;
file = req->lr_fid->lo_aux;
if (file->dir)
closedir(file->dir);
else {
close(file->fd);
file->fd = -1;
}
l9p_respond(req, NULL);
}
static void
fs_create(void *softc, struct l9p_request *req)
{
}
static void
fs_flush(void *softc, struct l9p_request *req)
{
l9p_respond(req, NULL);
}
static void
fs_open(void *softc, struct l9p_request *req)
{
struct l9p_connection *conn = req->lr_conn;
struct openfile *file;
struct stat st;
file = req->lr_fid->lo_aux;
stat(file->name, &st);
if (S_ISDIR(st.st_mode)) {
file->dir = opendir(file->name);
} else {
file->fd = open(file->name, O_RDONLY);
if (file->fd < 0) {
l9p_respond(req, "Permission denied");
return;
}
}
req->lr_resp.ropen.iounit = conn->lc_max_io_size;
l9p_respond(req, NULL);
}
static void
fs_read(void *softc, struct l9p_request *req)
{
struct openfile *file;
struct l9p_connection *conn = req->lr_conn;
struct l9p_stat l9stat;
file = req->lr_fid->lo_aux;
if (file->dir != NULL) {
struct dirent *d;
struct stat st;
for (;;) {
d = readdir(file->dir);
if (d) {
stat(d->d_name, &st);
dostat(&l9stat, d->d_name, &st);
if (l9p_pack_stat(req, &l9stat) != 0) {
seekdir(file->dir, -1);
break;
}
continue;
}
break;
}
} else {
size_t niov = l9p_truncate_iov(req->lr_data_iov, req->lr_data_niov, req->lr_req.io.count);
req->lr_resp.io.count = readv(file->fd, req->lr_data_iov, niov);
}
l9p_respond(req, NULL);
}
static void
fs_remove(void *softc, struct l9p_request *req)
{
}
static void
fs_stat(void *softc, struct l9p_request *req)
{
struct openfile *file;
struct stat st;
struct l9p_stat l9stat;
file = req->lr_fid->lo_aux;
stat(file->name, &st);
dostat(&req->lr_resp.rstat.stat, file->name, &st);
l9p_respond(req, NULL);
}
static void
fs_walk(void *softc, struct l9p_request *req)
{
int i;
struct stat buf;
struct openfile *file = (struct openfile *)req->lr_fid->lo_aux;
char *name = malloc(1024);
strcpy(name, file->name);
/* build full path. Stat full path. Done */
for (i = 0; i < req->lr_req.twalk.nwname; i++) {
strcat(name, "/");
strcat(name, req->lr_req.twalk.wname[i]);
if (stat(name, &buf) < 0){
l9p_respond(req, "No such file or directory");
free(name);
return;
}
req->lr_resp.rwalk.wqid[i].type = buf.st_mode&S_IFMT >> 8;
req->lr_resp.rwalk.wqid[i].path = buf.st_ino;
}
req->lr_newfid->lo_aux = open_fid(name);
req->lr_resp.rwalk.nwqid = i;
free(name);
l9p_respond(req, NULL);
}
static void
fs_write(void *softc, struct l9p_request *req)
{
}
static void
fs_wstat(void *softc, struct l9p_request *req)
{
}
int
l9p_backend_fs_init(struct l9p_backend **backendp, const char *root)
{
struct l9p_backend *backend;
struct fs_softc *sc;
backend = malloc(sizeof(*backend));
backend->attach = fs_attach;
backend->clunk = fs_clunk;
backend->create = fs_create;
backend->flush = fs_flush;
backend->open = fs_open;
backend->read = fs_read;
backend->remove = fs_remove;
backend->stat = fs_stat;
backend->walk = fs_walk;
backend->write = fs_write;
backend->wstat = fs_wstat;
sc = malloc(sizeof(*sc));
sc->fs_rootpath = strdup(root);
backend->softc = sc;
*backendp = backend;
return (0);
}