mc/vfs/vfs.c

999 lines
22 KiB
C

/* Virtual File System switch code
Copyright (C) 1995 The Free Software Foundation
Written by: 1995 Miguel de Icaza
1995 Jakub Jelinek
1998 Pavel Machek
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License
as published by the Free Software Foundation; either version 2 of
the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Warning: funtions like extfs_lstat() have right to destroy any
* strings you pass to them. This is acutally ok as you g_strdup what
* you are passing to them, anyway; still, beware. */
/* Namespace: exports *many* functions with vfs_ prefix; exports
parse_ls_lga and friends which do not have that prefix. */
#include <config.h>
#include <stdio.h>
#include <stdlib.h> /* For atol() */
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <signal.h>
#include <ctype.h> /* is_digit() */
#include "utilvfs.h"
#include "gc.h"
#include "vfs.h"
#ifdef USE_NETCODE
# include "tcputil.h"
#endif
#include "ftpfs.h"
#include "mcfs.h"
#include "smbfs.h"
#include "local.h"
/* They keep track of the current directory */
static struct vfs_class *current_vfs;
static char *current_dir;
struct vfs_openfile {
int handle;
struct vfs_class *vclass;
void *fsinfo;
};
static GSList *vfs_openfiles;
#define VFS_FIRST_HANDLE 100
static struct vfs_class *localfs_class;
/* Create new VFS handle and put it to the list */
static int
vfs_new_handle (struct vfs_class *vclass, void *fsinfo)
{
static int vfs_handle_counter = VFS_FIRST_HANDLE;
struct vfs_openfile *h;
h = g_new (struct vfs_openfile, 1);
h->handle = vfs_handle_counter++;
h->fsinfo = fsinfo;
h->vclass = vclass;
vfs_openfiles = g_slist_prepend (vfs_openfiles, h);
return h->handle;
}
/* Function to match handle, passed to g_slist_find_custom() */
static gint
vfs_cmp_handle (gconstpointer a, gconstpointer b)
{
if (!a)
return 1;
return ((struct vfs_openfile *) a)->handle != (long) b;
}
/* Find VFS class by file handle */
static inline struct vfs_class *
vfs_op (int handle)
{
GSList *l;
struct vfs_openfile *h;
l = g_slist_find_custom (vfs_openfiles, (void *) (long) handle,
vfs_cmp_handle);
if (!l)
return NULL;
h = (struct vfs_openfile *) l->data;
if (!h)
return NULL;
return h->vclass;
}
/* Find private file data by file handle */
static inline void *
vfs_info (int handle)
{
GSList *l;
struct vfs_openfile *h;
l = g_slist_find_custom (vfs_openfiles, (void *) (long) handle,
vfs_cmp_handle);
if (!l)
return NULL;
h = (struct vfs_openfile *) l->data;
if (!h)
return NULL;
return h->fsinfo;
}
/* Free open file data for given file handle */
static inline void
vfs_free_handle (int handle)
{
GSList *l;
l = g_slist_find_custom (vfs_openfiles, (void *) (long) handle,
vfs_cmp_handle);
vfs_openfiles = g_slist_delete_link (vfs_openfiles, l);
}
static struct vfs_class *vfs_list;
int
vfs_register_class (struct vfs_class *vfs)
{
if (vfs->init) /* vfs has own initialization function */
if (!(*vfs->init)(vfs)) /* but it failed */
return 0;
vfs->next = vfs_list;
vfs_list = vfs;
return 1;
}
/* Return VFS class for the given prefix */
static struct vfs_class *
vfs_prefix_to_class (char *prefix)
{
struct vfs_class *vfs;
/* Avoid last class (localfs) that would accept any prefix */
for (vfs = vfs_list; vfs->next; vfs = vfs->next) {
if (vfs->which) {
if ((*vfs->which) (vfs, prefix) == -1)
continue;
return vfs;
}
if (vfs->prefix
&& !strncmp (prefix, vfs->prefix, strlen (vfs->prefix)))
return vfs;
}
return NULL;
}
/* Strip known vfs suffixes from a filename (possible improvement: strip
suffix from last path component).
Returns a malloced string which has to be freed. */
char *
vfs_strip_suffix_from_filename (const char *filename)
{
struct vfs_class *vfs;
char *semi;
char *p;
if (!filename)
vfs_die ("vfs_strip_suffix_from_path got NULL: impossible");
p = g_strdup (filename);
if (!(semi = strrchr (p, '#')))
return p;
/* Avoid last class (localfs) that would accept any prefix */
for (vfs = vfs_list; vfs->next; vfs = vfs->next) {
if (vfs->which) {
if ((*vfs->which) (vfs, semi + 1) == -1)
continue;
*semi = '\0'; /* Found valid suffix */
return p;
}
if (vfs->prefix
&& !strncmp (semi + 1, vfs->prefix, strlen (vfs->prefix))) {
*semi = '\0'; /* Found valid suffix */
return p;
}
}
return p;
}
static inline int
path_magic (const char *path)
{
struct stat buf;
if (!stat(path, &buf))
return 0;
return 1;
}
/*
* Splits path '/p1#op/inpath' into inpath,op; returns which vfs it is.
* What is left in path is p1. You still want to g_free(path), you DON'T
* want to free neither *inpath nor *op
*/
struct vfs_class *
vfs_split (char *path, char **inpath, char **op)
{
char *semi;
char *slash;
struct vfs_class *ret;
if (!path)
vfs_die("Cannot split NULL");
semi = strrchr (path, '#');
if (!semi || !path_magic(path))
return NULL;
slash = strchr (semi, PATH_SEP);
*semi = 0;
if (op)
*op = NULL;
if (inpath)
*inpath = NULL;
if (slash)
*slash = 0;
if ((ret = vfs_prefix_to_class (semi+1))){
if (op)
*op = semi + 1;
if (inpath)
*inpath = slash ? slash + 1 : NULL;
return ret;
}
if (slash)
*slash = PATH_SEP;
ret = vfs_split (path, inpath, op);
*semi = '#';
return ret;
}
static struct vfs_class *
_vfs_get_class (char *path)
{
char *semi;
char *slash;
struct vfs_class *ret;
g_return_val_if_fail(path, NULL);
semi = strrchr (path, '#');
if (!semi || !path_magic (path))
return NULL;
slash = strchr (semi, PATH_SEP);
*semi = 0;
if (slash)
*slash = 0;
ret = vfs_prefix_to_class (semi+1);
if (slash)
*slash = PATH_SEP;
if (!ret)
ret = _vfs_get_class (path);
*semi = '#';
return ret;
}
struct vfs_class *
vfs_get_class (const char *pathname)
{
struct vfs_class *vfs;
char *path = g_strdup (pathname);
vfs = _vfs_get_class (path);
g_free (path);
if (!vfs)
vfs = localfs_class;
return vfs;
}
static int
ferrno (struct vfs_class *vfs)
{
return vfs->ferrno ? (*vfs->ferrno)(vfs) : E_UNKNOWN;
/* Hope that error message is obscure enough ;-) */
}
int
mc_open (const char *filename, int flags, ...)
{
int mode;
void *info;
va_list ap;
char *file = vfs_canon (filename);
struct vfs_class *vfs = vfs_get_class (file);
/* Get the mode flag */
if (flags & O_CREAT) {
va_start (ap, flags);
mode = va_arg (ap, int);
va_end (ap);
} else
mode = 0;
if (!vfs->open) {
g_free (file);
errno = -EOPNOTSUPP;
return -1;
}
info = (*vfs->open) (vfs, file, flags, mode); /* open must be supported */
g_free (file);
if (!info){
errno = ferrno (vfs);
return -1;
}
return vfs_new_handle (vfs, info);
}
#define MC_NAMEOP(name, inarg, callarg) \
int mc_##name inarg \
{ \
struct vfs_class *vfs; \
int result; \
char *mpath = vfs_canon (path); \
vfs = vfs_get_class (mpath); \
result = vfs->name ? (*vfs->name)callarg : -1; \
g_free (mpath); \
if (result == -1) \
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
return result; \
}
MC_NAMEOP (chmod, (const char *path, int mode), (vfs, path, mode))
MC_NAMEOP (chown, (const char *path, int owner, int group), (vfs, path, owner, group))
MC_NAMEOP (utime, (const char *path, struct utimbuf *times), (vfs, path, times))
MC_NAMEOP (readlink, (const char *path, char *buf, int bufsiz), (vfs, path, buf, bufsiz))
MC_NAMEOP (unlink, (const char *path), (vfs, path))
MC_NAMEOP (symlink, (const char *name1, const char *path), (vfs, name1, path))
MC_NAMEOP (mkdir, (const char *path, mode_t mode), (vfs, path, mode))
MC_NAMEOP (rmdir, (const char *path), (vfs, path))
MC_NAMEOP (mknod, (const char *path, int mode, int dev), (vfs, path, mode, dev))
#define MC_HANDLEOP(name, inarg, callarg) \
int mc_##name inarg \
{ \
struct vfs_class *vfs; \
int result; \
if (handle == -1) \
return -1; \
vfs = vfs_op (handle); \
result = vfs->name ? (*vfs->name)callarg : -1; \
if (result == -1) \
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
return result; \
}
MC_HANDLEOP(read, (int handle, char *buffer, int count), (vfs_info (handle), buffer, count) )
MC_HANDLEOP (write, (int handle, const char *buf, int nbyte), (vfs_info (handle), buf, nbyte))
#define MC_RENAMEOP(name) \
int mc_##name (const char *fname1, const char *fname2) \
{ \
struct vfs_class *vfs; \
int result; \
char *name2, *name1 = vfs_canon (fname1); \
vfs = vfs_get_class (name1); \
name2 = vfs_canon (fname2); \
if (vfs != vfs_get_class (name2)){ \
errno = EXDEV; \
g_free (name1); \
g_free (name2); \
return -1; \
} \
result = vfs->name ? (*vfs->name)(vfs, name1, name2) : -1; \
g_free (name1); \
g_free (name2); \
if (result == -1) \
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP; \
return result; \
}
MC_RENAMEOP (link)
MC_RENAMEOP (rename)
int
mc_ctl (int handle, int ctlop, void *arg)
{
struct vfs_class *vfs = vfs_op (handle);
return vfs->ctl ? (*vfs->ctl)(vfs_info (handle), ctlop, arg) : 0;
}
int
mc_setctl (const char *path, int ctlop, void *arg)
{
struct vfs_class *vfs;
int result;
char *mpath;
if (!path)
vfs_die("You don't want to pass NULL to mc_setctl.");
mpath = vfs_canon (path);
vfs = vfs_get_class (mpath);
result = vfs->setctl ? (*vfs->setctl)(vfs, mpath, ctlop, arg) : 0;
g_free (mpath);
return result;
}
int
mc_close (int handle)
{
struct vfs_class *vfs;
int result;
if (handle == -1 || !vfs_info (handle))
return -1;
vfs = vfs_op (handle);
if (handle < 3)
return close (handle);
if (!vfs->close)
vfs_die ("VFS must support close.\n");
result = (*vfs->close)(vfs_info (handle));
vfs_free_handle (handle);
if (result == -1)
errno = ferrno (vfs);
return result;
}
DIR *
mc_opendir (const char *dirname)
{
int handle, *handlep;
void *info;
struct vfs_class *vfs;
char *dname;
dname = vfs_canon (dirname);
vfs = vfs_get_class (dname);
info = vfs->opendir ? (*vfs->opendir)(vfs, dname) : NULL;
g_free (dname);
if (!info){
errno = vfs->opendir ? ferrno (vfs) : E_NOTSUPP;
return NULL;
}
handle = vfs_new_handle (vfs, info);
handlep = g_new (int, 1);
*handlep = handle;
return (DIR *) handlep;
}
struct dirent *
mc_readdir (DIR *dirp)
{
int handle;
struct vfs_class *vfs;
struct dirent *result = NULL;
if (!dirp) {
errno = EFAULT;
return NULL;
}
handle = *(int *) dirp;
vfs = vfs_op (handle);
if (vfs->readdir)
result = (*vfs->readdir) (vfs_info (handle));
if (!result)
errno = vfs->readdir ? ferrno (vfs) : E_NOTSUPP;
return result;
}
int
mc_closedir (DIR *dirp)
{
int handle = *(int *) dirp;
struct vfs_class *vfs = vfs_op (handle);
int result;
result = vfs->closedir ? (*vfs->closedir)(vfs_info (handle)) : -1;
vfs_free_handle (handle);
g_free (dirp);
return result;
}
int mc_stat (const char *filename, struct stat *buf) {
struct vfs_class *vfs;
int result;
char *path;
path = vfs_canon (filename); vfs = vfs_get_class (path);
result = vfs->stat ? (*vfs->stat) (vfs, path, buf) : -1;
g_free (path);
if (result == -1)
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
return result;
}
int mc_lstat (const char *filename, struct stat *buf) {
struct vfs_class *vfs;
int result;
char *path;
path = vfs_canon (filename); vfs = vfs_get_class (path);
result = vfs->lstat ? (*vfs->lstat) (vfs, path, buf) : -1;
g_free (path);
if (result == -1)
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
return result;
}
int mc_fstat (int handle, struct stat *buf) {
struct vfs_class *vfs;
int result;
if (handle == -1)
return -1;
vfs = vfs_op (handle);
result = vfs->fstat ? (*vfs->fstat) (vfs_info (handle), buf) : -1;
if (result == -1)
errno = vfs->name ? ferrno (vfs) : E_NOTSUPP;
return result;
}
/*
* Return current directory. If it's local, reread the current directory
* from the OS. You must g_strdup() whatever this function returns.
*/
static const char *
_vfs_get_cwd (void)
{
char *p;
struct stat my_stat, my_stat2;
if (!_vfs_get_class (current_dir)) {
p = g_get_current_dir ();
if (!p) /* One of the directories in the path is not readable */
return current_dir;
/* Otherwise check if it is O.K. to use the current_dir */
if (!cd_symlinks || mc_stat (p, &my_stat)
|| mc_stat (current_dir, &my_stat2)
|| my_stat.st_ino != my_stat2.st_ino
|| my_stat.st_dev != my_stat2.st_dev) {
g_free (current_dir);
current_dir = p;
return p;
} /* Otherwise we return current_dir below */
g_free (p);
}
return current_dir;
}
static void
vfs_setup_wd (void)
{
current_dir = g_strdup (PATH_SEP_STR);
_vfs_get_cwd ();
if (strlen (current_dir) > MC_MAXPATHLEN - 2)
vfs_die ("Current dir too long.\n");
current_vfs = vfs_get_class (current_dir);
}
/*
* Return current directory. If it's local, reread the current directory
* from the OS. Put directory to the provided buffer.
*/
char *
mc_get_current_wd (char *buffer, int size)
{
const char *cwd = _vfs_get_cwd ();
g_strlcpy (buffer, cwd, size);
return buffer;
}
/*
* Return current directory without any OS calls.
*/
char *
vfs_get_current_dir (void)
{
return current_dir;
}
off_t mc_lseek (int fd, off_t offset, int whence)
{
struct vfs_class *vfs;
int result;
if (fd == -1)
return -1;
vfs = vfs_op (fd);
result = vfs->lseek ? (*vfs->lseek)(vfs_info (fd), offset, whence) : -1;
if (result == -1)
errno = vfs->lseek ? ferrno (vfs) : E_NOTSUPP;
return result;
}
/*
* remove //, /./ and /../
*/
#define ISSLASH(a) (!a || (a == '/'))
char *
vfs_canon (const char *path)
{
if (!path)
vfs_die("Cannot canonicalize NULL");
/* Relative to current directory */
if (*path != PATH_SEP){
char *local, *result;
local = concat_dir_and_file (current_dir, path);
result = vfs_canon (local);
g_free (local);
return result;
}
/*
* So we have path of following form:
* /p1/p2#op/.././././p3#op/p4. Good luck.
*/
{
char *result = g_strdup (path);
canonicalize_pathname (result);
return result;
}
}
/*
* VFS chdir.
* Return 0 on success, -1 on failure.
*/
int
mc_chdir (const char *path)
{
char *new_dir;
struct vfs_class *old_vfs, *new_vfs;
vfsid old_vfsid;
int result;
new_dir = vfs_canon (path);
new_vfs = vfs_get_class (new_dir);
if (!new_vfs->chdir) {
g_free (new_dir);
return -1;
}
result = (*new_vfs->chdir) (new_vfs, new_dir);
if (result == -1) {
errno = ferrno (new_vfs);
g_free (new_dir);
return -1;
}
old_vfsid = vfs_getid (current_vfs, current_dir);
old_vfs = current_vfs;
/* Actually change directory */
g_free (current_dir);
current_dir = new_dir;
current_vfs = new_vfs;
/* This function uses the new current_dir implicitly */
vfs_stamp_create (old_vfs, old_vfsid);
/* Sometimes we assume no trailing slash on cwd */
if (*current_dir) {
char *p;
p = strchr (current_dir, 0) - 1;
if (*p == PATH_SEP && p > current_dir)
*p = 0;
}
return 0;
}
/* Return 1 is the current VFS class is local */
int
vfs_current_is_local (void)
{
return (current_vfs->flags & VFSF_LOCAL) != 0;
}
/* Return flags of the VFS class of the given filename */
int
vfs_file_class_flags (const char *filename)
{
struct vfs_class *vfs;
char *fname;
fname = vfs_canon (filename);
vfs = vfs_get_class (fname);
g_free (fname);
return vfs->flags;
}
#ifdef HAVE_MMAP
static struct mc_mmapping {
caddr_t addr;
void *vfs_info;
struct vfs_class *vfs;
struct mc_mmapping *next;
} *mc_mmaparray = NULL;
caddr_t
mc_mmap (caddr_t addr, size_t len, int prot, int flags, int fd, off_t offset)
{
struct vfs_class *vfs;
caddr_t result;
struct mc_mmapping *mcm;
if (fd == -1)
return (caddr_t) -1;
vfs = vfs_op (fd);
result = vfs->mmap ? (*vfs->mmap)(vfs, addr, len, prot, flags, vfs_info (fd), offset) : (caddr_t)-1;
if (result == (caddr_t)-1){
errno = ferrno (vfs);
return (caddr_t)-1;
}
mcm =g_new (struct mc_mmapping, 1);
mcm->addr = result;
mcm->vfs_info = vfs_info (fd);
mcm->vfs = vfs;
mcm->next = mc_mmaparray;
mc_mmaparray = mcm;
return result;
}
int
mc_munmap (caddr_t addr, size_t len)
{
struct mc_mmapping *mcm, *mcm2 = NULL;
for (mcm = mc_mmaparray; mcm != NULL; mcm2 = mcm, mcm = mcm->next){
if (mcm->addr == addr){
if (mcm2 == NULL)
mc_mmaparray = mcm->next;
else
mcm2->next = mcm->next;
if (mcm->vfs->munmap)
(*mcm->vfs->munmap)(mcm->vfs, addr, len, mcm->vfs_info);
g_free (mcm);
return 0;
}
}
return -1;
}
#endif
static char *
mc_def_getlocalcopy (struct vfs_class *vfs, const char *filename)
{
char *tmp;
int fdin, fdout, i;
char buffer[8192];
struct stat mystat;
fdin = mc_open (filename, O_RDONLY | O_LINEAR);
if (fdin == -1)
return NULL;
fdout = vfs_mkstemps (&tmp, "vfs", filename);
if (fdout == -1)
goto fail;
while ((i = mc_read (fdin, buffer, sizeof (buffer))) > 0) {
if (write (fdout, buffer, i) != i)
goto fail;
}
if (i == -1)
goto fail;
i = mc_close (fdin);
fdin = -1;
if (i == -1)
goto fail;
if (close (fdout) == -1) {
fdout = -1;
goto fail;
}
if (mc_stat (filename, &mystat) != -1) {
chmod (tmp, mystat.st_mode);
}
return tmp;
fail:
if (fdout != -1)
close (fdout);
if (fdin != -1)
mc_close (fdin);
g_free (tmp);
return NULL;
}
char *
mc_getlocalcopy (const char *pathname)
{
char *result;
char *path = vfs_canon (pathname);
struct vfs_class *vfs = vfs_get_class (path);
result = vfs->getlocalcopy ? (*vfs->getlocalcopy)(vfs, path) :
mc_def_getlocalcopy (vfs, path);
g_free (path);
if (!result)
errno = ferrno (vfs);
return result;
}
static int
mc_def_ungetlocalcopy (struct vfs_class *vfs, const char *filename,
const char *local, int has_changed)
{
int fdin = -1, fdout = -1, i;
if (has_changed) {
char buffer[8192];
if (!vfs->write)
goto failed;
fdin = open (local, O_RDONLY);
if (fdin == -1)
goto failed;
fdout = mc_open (filename, O_WRONLY | O_TRUNC);
if (fdout == -1)
goto failed;
while ((i = read (fdin, buffer, sizeof (buffer))) > 0) {
if (mc_write (fdout, buffer, i) != i)
goto failed;
}
if (i == -1)
goto failed;
if (close (fdin) == -1) {
fdin = -1;
goto failed;
}
fdin = -1;
if (mc_close (fdout) == -1) {
fdout = -1;
goto failed;
}
}
unlink (local);
return 0;
failed:
message (1, _("Changes to file lost"), "%s", filename);
if (fdout != -1)
mc_close (fdout);
if (fdin != -1)
close (fdin);
unlink (local);
return -1;
}
int
mc_ungetlocalcopy (const char *pathname, const char *local, int has_changed)
{
int return_value = 0;
char *path = vfs_canon (pathname);
struct vfs_class *vfs = vfs_get_class (path);
return_value = vfs->ungetlocalcopy ?
(*vfs->ungetlocalcopy)(vfs, path, local, has_changed) :
mc_def_ungetlocalcopy (vfs, path, local, has_changed);
g_free (path);
return return_value;
}
void
vfs_init (void)
{
/* localfs needs to be the first one */
init_localfs();
/* fallback value for vfs_get_class() */
localfs_class = vfs_list;
init_extfs ();
init_sfs ();
init_tarfs ();
init_cpiofs ();
#ifdef USE_EXT2FSLIB
init_undelfs ();
#endif /* USE_EXT2FSLIB */
#ifdef USE_NETCODE
tcp_init();
init_ftpfs ();
init_fish ();
#ifdef WITH_SMBFS
init_smbfs ();
#endif /* WITH_SMBFS */
#ifdef WITH_MCFS
init_mcfs ();
#endif /* WITH_MCFS */
#endif /* USE_NETCODE */
vfs_setup_wd ();
}
void
vfs_shut (void)
{
struct vfs_class *vfs;
vfs_gc_done ();
g_free (current_dir);
for (vfs = vfs_list; vfs; vfs = vfs->next)
if (vfs->done)
(*vfs->done) (vfs);
g_slist_free (vfs_openfiles);
}
/*
* These ones grab information from the VFS
* and handles them to an upper layer
*/
void
vfs_fill_names (fill_names_f func)
{
struct vfs_class *vfs;
for (vfs=vfs_list; vfs; vfs=vfs->next)
if (vfs->fill_names)
(*vfs->fill_names) (vfs, func);
}
/*
* Returns vfs path corresponding to given url. If passed string is
* not recognized as url, g_strdup(url) is returned.
*/
char *
vfs_translate_url (const char *url)
{
if (strncmp (url, "ftp://", 6) == 0)
return g_strconcat ("/#ftp:", url + 6, (char *) NULL);
else if (strncmp (url, "a:", 2) == 0)
return g_strdup ("/#a");
else
return g_strdup (url);
}
int vfs_file_is_local (const char *filename)
{
return vfs_file_class_flags (filename) & VFSF_LOCAL;
}