mc/vfs/sfs.c

427 lines
9.3 KiB
C

/*
* Single File fileSystem
*
* Copyright 1998 Pavel Machek, distribute under GPL
*
* This defines whole class of filesystems which contain single file
* inside. It is somehow similar to extfs, except that extfs makes
* whole virtual trees and we do only single virtual files.
*
* If you want to gunzip something, you should open it with #ugz
* suffix, DON'T try to gunzip it yourself.
*
* Namespace: exports vfs_sfs_ops */
#include <config.h>
#include <errno.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include "utilvfs.h"
#include "vfs.h"
#include "local.h"
#include "../src/execute.h"
struct cachedfile {
char *name, *cache;
struct cachedfile *next;
};
static struct cachedfile *head;
static struct vfs_class vfs_sfs_ops;
#define MAXFS 32
static int sfs_no = 0;
static char *sfs_prefix[ MAXFS ];
static char *sfs_command[ MAXFS ];
static int sfs_flags[ MAXFS ];
#define F_1 1
#define F_2 2
#define F_NOLOCALCOPY 4
#define F_FULLMATCH 8
static int uptodate (char *name, char *cache)
{
return 1;
}
static int vfmake (struct vfs_class *me, char *name, char *cache)
{
char *inpath, *op;
int w;
char pad [10240];
char *s, *t = pad;
int was_percent = 0;
vfs_split (name, &inpath, &op);
if ((w = (*me->which) (me, op)) == -1)
vfs_die ("This cannot happen... Hopefully.\n");
if ((sfs_flags[w] & F_1) || (!strcmp (name, "/"))) ; else return -1;
/* if ((sfs_flags[w] & F_2) || (!inpath) || (!*inpath)); else return -1; */
if (!(sfs_flags[w] & F_NOLOCALCOPY)) {
s = mc_getlocalcopy (name);
if (!s)
return -1;
name = name_quote (s, 0);
g_free (s);
} else
name = name_quote (name, 0);
#define COPY_CHAR if (t-pad>sizeof(pad)) { g_free (name); return -1; } else *t++ = *s;
#define COPY_STRING(a) if ((t-pad)+strlen(a)>sizeof(pad)) { g_free (name); return -1; } else { strcpy (t, a); t+= strlen(a); }
for (s = sfs_command[w]; *s; s++) {
if (was_percent) {
char *ptr = NULL;
was_percent = 0;
switch (*s) {
case '1': ptr = name; break;
case '2': ptr = op + strlen (sfs_prefix[w]); break;
case '3': ptr = cache; break;
case '%': COPY_CHAR; continue;
}
COPY_STRING (ptr);
} else {
if (*s == '%')
was_percent = 1;
else
COPY_CHAR;
}
}
g_free (name);
open_error_pipe ();
if (my_system (EXECUTE_AS_SHELL, "/bin/sh", pad)) {
close_error_pipe (1, NULL);
return -1;
}
close_error_pipe (0, NULL);
return 0; /* OK */
}
static char *
redirect (struct vfs_class *me, char *name)
{
struct cachedfile *cur = head;
char *cache;
int handle;
while (cur) {
/* FIXME: when not uptodate, we might want to kill cache
* file immediately, not to wait until timeout. */
if ((!strcmp (name, cur->name))
&& (uptodate (cur->name, cur->cache))) {
vfs_stamp (&vfs_sfs_ops, cur);
return cur->cache;
}
cur = cur->next;
}
handle = mc_mkstemps (&cache, "sfs", NULL);
if (handle == -1) {
return "/SOMEONE_PLAYING_DIRTY_TMP_TRICKS_ON_US";
}
close (handle);
if (!vfmake (me, name, cache)) {
cur = g_new (struct cachedfile, 1);
cur->name = g_strdup (name);
cur->cache = cache;
cur->next = head;
head = cur;
vfs_add_noncurrent_stamps (&vfs_sfs_ops, (vfsid) head, NULL);
return cache;
}
unlink (cache);
g_free (cache);
return "/I_MUST_NOT_EXIST";
}
static void *
sfs_open (struct vfs_class *me, char *path, int flags, int mode)
{
int *sfs_info;
int fd;
path = redirect (me, path);
fd = open (path, NO_LINEAR(flags), mode);
if (fd == -1)
return 0;
sfs_info = g_new (int, 1);
*sfs_info = fd;
return sfs_info;
}
static int sfs_stat (struct vfs_class *me, char *path, struct stat *buf)
{
path = redirect (me, path);
return stat (path, buf);
}
static int sfs_lstat (struct vfs_class *me, char *path, struct stat *buf)
{
path = redirect (me, path);
#ifndef HAVE_STATLSTAT
return lstat (path, buf);
#else
return statlstat (path, buf);
#endif
}
static int sfs_chmod (struct vfs_class *me, char *path, int mode)
{
path = redirect (me, path);
return chmod (path, mode);
}
static int sfs_chown (struct vfs_class *me, char *path, int owner, int group)
{
path = redirect (me, path);
return chown (path, owner, group);
}
static int sfs_utime (struct vfs_class *me, char *path, struct utimbuf *times)
{
path = redirect (me, path);
return utime (path, times);
}
static int sfs_readlink (struct vfs_class *me, char *path, char *buf, int size)
{
path = redirect (me, path);
return readlink (path, buf, size);
}
static vfsid
sfs_getid (struct vfs_class *me, const char *path, struct vfs_stamping **parent)
{ /* FIXME: what should I do? */
struct vfs_class *v;
vfsid id;
struct vfs_stamping *par;
struct cachedfile *cur = head;
while (cur) {
if (!strcmp (path, cur->name))
break;
cur = cur->next;
}
*parent = NULL;
if (!cur)
return (vfsid) (-1);
{
char *path2 = g_strdup (path);
/* Strip suffix which led to this being sfs */
v = vfs_split (path2, NULL, NULL);
/* ... and learn whoever was the parent system */
v = vfs_split (path2, NULL, NULL);
id = (*v->getid) (v, path2, &par);
g_free (path2);
}
if (id != (vfsid) - 1) {
*parent = g_new (struct vfs_stamping, 1);
(*parent)->v = v;
(*parent)->id = id;
(*parent)->parent = par;
(*parent)->next = NULL;
}
return (vfsid) cur;
}
static void sfs_free (vfsid id)
{
struct cachedfile *which = (struct cachedfile *) id;
struct cachedfile *cur, *prev;
for (cur = head, prev = 0; cur && cur != which; prev = cur, cur = cur->next)
;
if (!cur)
vfs_die( "Free of thing which is unknown to me\n" );
unlink (cur->cache);
if (prev)
prev->next = cur->next;
else
head = cur->next;
g_free (cur->cache);
g_free (cur->name);
g_free (cur);
}
static void sfs_fill_names (struct vfs_class *me, void (*func)(char *))
{
struct cachedfile *cur = head;
while (cur){
(*func)(cur->name);
cur = cur->next;
}
}
static int sfs_nothingisopen (vfsid id)
{
/* FIXME: Investigate whether have to guard this like in
the other VFSs (see fd_usage in extfs) -- Norbert */
return 1;
}
static char *sfs_getlocalcopy (struct vfs_class *me, char *path)
{
path = redirect (me, path);
return g_strdup (path);
}
static int sfs_ungetlocalcopy (struct vfs_class *me, char *path, char *local, int has_changed)
{
g_free(local);
return 0;
}
static int sfs_init (struct vfs_class *me)
{
char *mc_sfsini;
FILE *cfg;
mc_sfsini = concat_dir_and_file (mc_home, "extfs" PATH_SEP_STR "sfs.ini");
cfg = fopen (mc_sfsini, "r");
if (!cfg){
fprintf (stderr, _("Warning: file %s not found\n"), mc_sfsini);
g_free (mc_sfsini);
return 0;
}
g_free (mc_sfsini);
sfs_no = 0;
while (sfs_no < MAXFS){
char key[256];
char *c, *semi = NULL, flags = 0;
if (!fgets (key, sizeof (key), cfg))
break;
if (*key == '#')
continue;
for (c = key; *c; c++)
if ((*c == ':') || (*c == '/')){
semi = c;
if (*c == '/'){
*c = 0;
flags |= F_FULLMATCH;
}
break;
}
if (!semi){
fprintf (stderr, _("Warning: Invalid line in %s:\n%s\n"),
"sfs.ini", key);
continue;
}
c = semi + 1;
while ((*c != ' ') && (*c != '\t')) {
switch (*c) {
case '1': flags |= F_1; break;
case '2': flags |= F_2; break;
case 'R': flags |= F_NOLOCALCOPY; break;
default:
fprintf (stderr, _("Warning: Invalid flag %c in %s:\n%s\n"),
*c, "sfs.ini", key);
}
c++;
}
c++;
*(semi+1) = 0;
if ((semi = strchr (c, '\n')))
*semi = 0;
sfs_prefix [sfs_no] = g_strdup (key);
sfs_command [sfs_no] = g_strdup (c);
sfs_flags [sfs_no] = flags;
sfs_no++;
}
fclose (cfg);
return 1;
}
static void
sfs_done (struct vfs_class *me)
{
int i;
for (i = 0; i < sfs_no; i++){
g_free (sfs_prefix [i]);
g_free (sfs_command [i]);
sfs_prefix [i] = sfs_command [i] = NULL;
}
sfs_no = 0;
}
static int
sfs_which (struct vfs_class *me, char *path)
{
int i;
for (i = 0; i < sfs_no; i++)
if (sfs_flags [i] & F_FULLMATCH) {
if (!strcmp (path, sfs_prefix [i]))
return i;
} else
if (!strncmp (path, sfs_prefix [i], strlen (sfs_prefix [i])))
return i;
return -1;
}
void
init_sfs (void)
{
vfs_sfs_ops.name = "sfs";
vfs_sfs_ops.init = sfs_init;
vfs_sfs_ops.done = sfs_done;
vfs_sfs_ops.fill_names = sfs_fill_names;
vfs_sfs_ops.which = sfs_which;
vfs_sfs_ops.open = sfs_open;
vfs_sfs_ops.close = local_close;
vfs_sfs_ops.read = local_read;
vfs_sfs_ops.stat = sfs_stat;
vfs_sfs_ops.lstat = sfs_lstat;
vfs_sfs_ops.fstat = local_fstat;
vfs_sfs_ops.chmod = sfs_chmod;
vfs_sfs_ops.chown = sfs_chown;
vfs_sfs_ops.utime = sfs_utime;
vfs_sfs_ops.readlink = sfs_readlink;
vfs_sfs_ops.ferrno = local_errno;
vfs_sfs_ops.lseek = local_lseek;
vfs_sfs_ops.getid = sfs_getid;
vfs_sfs_ops.nothingisopen = sfs_nothingisopen;
vfs_sfs_ops.free = sfs_free;
vfs_sfs_ops.getlocalcopy = sfs_getlocalcopy;
vfs_sfs_ops.ungetlocalcopy = sfs_ungetlocalcopy;
#ifdef HAVE_MMAP
vfs_sfs_ops.mmap = local_mmap;
vfs_sfs_ops.munmap = local_munmap;
#endif
vfs_register_class (&vfs_sfs_ops);
}