now that we got rid of global variables, we can split the operations into their own file

This commit is contained in:
josch
2014-12-02 07:34:07 +01:00
parent 58e8e89771
commit 04dd1bcc71
4 changed files with 359 additions and 282 deletions

View File

@@ -30,80 +30,21 @@
#include <errno.h>
#include <sys/stat.h>
#include <bits/fcntl-linux.h>
#include <fuse/fuse_common.h>
#include <pwd.h>
#include <wordexp.h>
#include <stdint.h>
#include <fcntl.h>
#include <stdbool.h>
#include "../mfapi/mfconn.h"
#include "../mfapi/apicalls.h"
#include "hashtbl.h"
#include "operations.h"
#include "../utils/strings.h"
/* what you can safely assume about requests to your filesystem
*
* from: http://sourceforge.net/p/fuse/wiki/FuseInvariants/
*
* There are a number of assumptions that one can safely make when
* implementing a filesystem using fuse. This page should be completed with a
* set of such assumptions.
*
* - All requests are absolute, i.e. all paths begin with "/" and include the
* complete path to a file or a directory. Symlinks, "." and ".." are
* already resolved.
*
* - For every request you can get except for "Getattr()", "Read()" and
* "Write()", usually for every path argument (both source and destination
* for link and rename, but only the source for symlink), you will get a
* "Getattr()" request just before the callback.
*
* For example, suppose I store file names of files in a filesystem also into a
* database. To keep data in sync, I would like, for each filesystem operation
* that succeeds, to check if the file exists on the database. I just do this in
* the "Getattr()" call, since all other calls will be preceded by a getattr.
*
* - The value of the "st_dev" attribute in the "Getattr()" call are ignored
* by fuse and an appropriate anomynous device number is inserted instead.
*
* - The arguments for every request are already verified as much as
* possible. This means that, for example "readdir()" is only called with
* an existing directory name, "Readlink()" is only called with an existing
* symlink, "Symlink()" is only called if there isn't already another
* object with the requested linkname, "read()" and "Write()" are only
* called if the file has been opened with the correct flags.
*
* - The VFS also takes care of avoiding race conditions:
*
* - while "Unlink()" is running on a specific file, it cannot be interrupted
* by a "Chmod()", "Link()" or "Open()" call from a different thread on the
* same file.
*
* - while "Rmdir()" is running, no files can be created in the directory
* that "Rmdir()" is acting on.
*
* - If a request returns invalid values (e.g. in the structure returned by
* "Getattr()" or in the link target returned by "Symlink()") or if a
* request appears to have failed (e.g. if a "Create()" request succeds but
* a subsequent "Getattr()" (that fuse calls automatically) ndicates that
* no regular file has been created), the syscall returns EIO to the
* caller.
*/
enum {
KEY_HELP,
KEY_VERSION,
};
struct mediafirefs_context_private {
mfconn *conn;
folder_tree *tree;
char *configfile;
char *dircache;
char *filecache;
};
struct mediafirefs_user_options {
char *username;
char *password;
@@ -113,227 +54,6 @@ struct mediafirefs_user_options {
char *api_key;
};
struct mediafirefs_openfile {
int fd;
};
static void usage(const char *progname)
{
fprintf(stderr, "Usage %s [options] mountpoint\n"
"\n"
"general options:\n"
" -o opt[,opt...] mount options\n"
" -h, --help show this help\n"
" -V, --version show version information\n"
"\n"
"MediaFire FS options:\n"
" -o, --username str username\n"
" -p, --password str password\n"
" -c, --config file configuration file\n"
" --server domain server domain\n"
" -i, --app-id id App ID\n"
" -k, --api-key key API Key\n"
"\n"
"Notice that long options are separated from their arguments by\n"
"a space and not an equal sign.\n" "\n", progname);
}
static int mediafirefs_getattr(const char *path, struct stat *stbuf)
{
/*
* since getattr is called before every other call (except for getattr,
* read and write) wee only call folder_tree_update in the getattr call
* and not the others
*
* FIXME: only call folder_tree_update if it has not been called for a set
* amount of time
*/
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
folder_tree_update(ctx->tree, ctx->conn);
return folder_tree_getattr(ctx->tree, ctx->conn, path, stbuf);
}
static int mediafirefs_readdir(const char *path, void *buf,
fuse_fill_dir_t filldir, off_t offset,
struct fuse_file_info *info)
{
(void)offset;
(void)info;
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
return folder_tree_readdir(ctx->tree, ctx->conn, path, buf, filldir);
}
static void mediafirefs_destroy()
{
FILE *fd;
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
fprintf(stderr, "storing hashtable\n");
fd = fopen(ctx->dircache, "w+");
if (fd == NULL) {
fprintf(stderr, "cannot open %s for writing\n", ctx->dircache);
return;
}
folder_tree_store(ctx->tree, fd);
fclose(fd);
folder_tree_destroy(ctx->tree);
mfconn_destroy(ctx->conn);
}
static int mediafirefs_mkdir(const char *path, mode_t mode)
{
(void)mode;
char *dirname;
int retval;
char *basename;
const char *key;
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
/* we don't need to check whether the path already existed because the
* getattr call made before this one takes care of that
*/
/* before calling the remote function we check locally */
dirname = strdup(path);
/* remove possible trailing slash */
if (dirname[strlen(dirname) - 1] == '/') {
dirname[strlen(dirname) - 1] = '\0';
}
/* split into dirname and basename */
basename = strrchr(dirname, '/');
if (basename == NULL) {
fprintf(stderr, "cannot find slash\n");
return -ENOENT;
}
/* replace the slash by a terminating zero */
basename[0] = '\0';
/* basename points to the string after the last slash */
basename++;
/* check if the dirname is of zero length now. If yes, then the directory
* is to be created in the root */
if (dirname[0] == '\0') {
key = NULL;
} else {
key = folder_tree_path_get_key(ctx->tree, ctx->conn, dirname);
}
retval = mfconn_api_folder_create(ctx->conn, key, basename);
mfconn_update_secret_key(ctx->conn);
if (retval != 0) {
fprintf(stderr, "mfconn_api_folder_create unsuccessful\n");
// FIXME: find better errno in this case
return -EAGAIN;
}
free(dirname);
folder_tree_update(ctx->tree, ctx->conn);
return 0;
}
static int mediafirefs_rmdir(const char *path)
{
const char *key;
int retval;
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
/* no need to check
* - if path is directory
* - if directory is empty
* - if directory is root
*
* because getattr was called before and already made sure
*/
key = folder_tree_path_get_key(ctx->tree, ctx->conn, path);
if (key == NULL) {
fprintf(stderr, "key is NULL\n");
return -ENOENT;
}
retval = mfconn_api_folder_delete(ctx->conn, key);
mfconn_update_secret_key(ctx->conn);
if (retval != 0) {
fprintf(stderr, "mfconn_api_folder_create unsuccessful\n");
// FIXME: find better errno in this case
return -EAGAIN;
}
/* retrieve remote changes to not get out of sync */
folder_tree_update(ctx->tree, ctx->conn);
return 0;
}
static int mediafirefs_open(const char *path, struct fuse_file_info *file_info)
{
int fd;
struct mediafirefs_openfile *openfile;
struct mediafirefs_context_private *ctx;
ctx = fuse_get_context()->private_data;
if ((file_info->flags & O_ACCMODE) != O_RDONLY) {
fprintf(stderr, "can only open read-only");
return -EACCES;
}
fd = folder_tree_open_file(ctx->tree, ctx->conn, path);
if (fd < 0) {
fprintf(stderr, "folder_tree_file_open unsuccessful\n");
return fd;
}
openfile = malloc(sizeof(struct mediafirefs_openfile));
openfile->fd = fd;
file_info->fh = (uint64_t) openfile;
return 0;
}
static int mediafirefs_read(const char *path, char *buf, size_t size,
off_t offset, struct fuse_file_info *file_info)
{
(void)path;
return pread(((struct mediafirefs_openfile *)file_info->fh)->fd, buf, size,
offset);
}
static int mediafirefs_release(const char *path,
struct fuse_file_info *file_info)
{
(void)path;
struct mediafirefs_openfile *openfile =
(struct mediafirefs_openfile *)file_info->fh;
close(openfile->fd);
free(openfile);
return 0;
}
static struct fuse_operations mediafirefs_oper = {
.getattr = mediafirefs_getattr,
.readdir = mediafirefs_readdir,
@@ -358,6 +78,27 @@ static struct fuse_operations mediafirefs_oper = {
.write = mediafirefs_write,*/
};
static void usage(const char *progname)
{
fprintf(stderr, "Usage %s [options] mountpoint\n"
"\n"
"general options:\n"
" -o opt[,opt...] mount options\n"
" -h, --help show this help\n"
" -V, --version show version information\n"
"\n"
"MediaFire FS options:\n"
" -o, --username str username\n"
" -p, --password str password\n"
" -c, --config file configuration file\n"
" --server domain server domain\n"
" -i, --app-id id App ID\n"
" -k, --api-key key API Key\n"
"\n"
"Notice that long options are separated from their arguments by\n"
"a space and not an equal sign.\n" "\n", progname);
}
static int
mediafirefs_opt_proc(void *data, const char *arg, int key,
struct fuse_args *outargs)