Rewrite filesystem code (WIP)

This patch redoes the filesystem code from the FAT driver up to the
clipboard code in onplay.c.

Not every aspect of this is finished therefore it is still "WIP". I
don't wish to do too much at once (haha!). What is left to do is get
dircache back in the sim and find an implementation for the dircache
indicies in the tagcache and playlist code or do something else that
has the same benefit. Leaving these out for now does not make anything
unusable. All the basics are done.

Phone app code should probably get vetted (and app path handling
just plain rewritten as environment expansions); the SDL app and
Android run well.

Main things addressed:
1) Thread safety: There is none right now in the trunk code. Most of
what currently works is luck when multiple threads are involved or
multiple descriptors to the same file are open.

2) POSIX compliance: Many of the functions behave nothing like their
counterparts on a host system. This leads to inconsistent code or very
different behavior from native to hosted. One huge offender was
rename(). Going point by point would fill a book.

3) Actual running RAM usage: Many targets will use less RAM and less
stack space (some more RAM because I upped the number of cache buffers
for large memory). There's very little memory lying fallow in rarely-used
areas (see 'Key core changes' below). Also, all targets may open the same
number of directory streams whereas before those with less than 8MB RAM
were limited to 8, not 12 implying those targets will save slightly
less.

4) Performance: The test_disk plugin shows markedly improved performance,
particularly in the area of (uncached) directory scanning, due partly to
more optimal directory reading and to a better sector cache algorithm.
Uncached times tend to be better while there is a bit of a slowdown in
dircache due to it being a bit heavier of an implementation. It's not
noticeable by a human as far as I can say.

Key core changes:
1) Files and directories share core code and data structures.

2) The filesystem code knows which descriptors refer to same file.
This ensures that changes from one stream are appropriately reflected
in every open descriptor for that file (fileobj_mgr.c).

3) File and directory cache buffers are borrowed from the main sector
cache. This means that when they are not in use by a file, they are not
wasted, but used for the cache. Most of the time, only a few of them
are needed. It also means that adding more file and directory handles
is less expensive. All one must do in ensure a large enough cache to
borrow from.

4) Relative path components are supported and the namespace is unified.
It does not support full relative paths to an implied current directory;
what is does support is use of "." and "..". Adding the former would
not be very difficult. The namespace is unified in the sense that
volumes may be specified several times along with relative parts, e.g.:
"/<0>/foo/../../<1>/bar" :<=> "/<1>/bar".

5) Stack usage is down due to sharing of data, static allocation and
less duplication of strings on the stack. This requires more
serialization than I would like but since the number of threads is
limited to a low number, the tradoff in favor of the stack seems
reasonable.

6) Separates and heirarchicalizes (sic) the SIM and APP filesystem
code. SIM path and volume handling is just like the target. Some
aspects of the APP file code get more straightforward (e.g. no path
hashing is needed).

Dircache:
Deserves its own section. Dircache is new but pays homage to the old.
The old one was not compatible and so it, since it got redone, does
all the stuff it always should have done such as:

1) It may be update and used at any time during the build process.
No longer has one to wait for it to finish building to do basic file
management (create, remove, rename, etc.).

2) It does not need to be either fully scanned or completely disabled;
it can be incomplete (i.e. overfilled, missing paths), still be
of benefit and be correct.

3) Handles mounting and dismounting of individual volumes which means
a full rebuild is not needed just because you pop a new SD card in the
slot. Now, because it reuses its freed entry data, may rebuild only
that volume.

4) Much more fundamental to the file code. When it is built, it is
the keeper of the master file list whether enabled or not ("disabled"
is just a state of the cache). Its must always to ready to be started
and bind all streams opened prior to being enabled.

5) Maintains any short filenames in OEM format which means that it does
not need to be rebuilt when changing the default codepage.

Miscellaneous Compatibility:
1) Update any other code that would otherwise not work such as the
hotswap mounting code in various card drivers.

2) File management: Clipboard needed updating because of the behavioral
changes. Still needs a little more work on some finer points.

3) Remove now-obsolete functionality such as the mutex's "no preempt"
flag (which was only for the prior FAT driver).

4) struct dirinfo uses time_t rather than raw FAT directory entry
time fields. I plan to follow up on genericizing everything there
(i.e. no FAT attributes).

5) unicode.c needed some redoing so that the file code does not try
try to load codepages during a scan, which is actually a problem with
the current code. The default codepage, if any is required, is now
kept in RAM separarately (bufalloced) from codepages specified to
iso_decode() (which must not be bufalloced because the conversion
may be done by playback threads).

Brings with it some additional reusable core code:
1) Revised file functions: Reusable code that does things such as
safe path concatenation and parsing without buffer limitations or
data duplication. Variants that copy or alter the input path may be
based off these.

To do:
1) Put dircache functionality back in the sim. Treating it internally
as a different kind of file system seems the best approach at this
time.

2) Restore use of dircache indexes in the playlist and database or
something effectively the same. Since the cache doesn't have to be
complete in order to be used, not getting a hit on the cache doesn't
unambiguously say if the path exists or not.

Change-Id: Ia30f3082a136253e3a0eae0784e3091d138915c8
Reviewed-on: http://gerrit.rockbox.org/566
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Tested: Michael Sevakis <jethead71@rockbox.org>

1 files changed, 517 insertions, 327 deletions

diff --git a/apps/onplay.c b/apps/onplay.c
index 7c5f517090..091680e949 100644
--- a/apps/onplay.c
+++ b/apps/onplay.c
@@ -62,16 +62,13 @@
 #include "statusbar-skinned.h"
 #include "pitchscreen.h"
 #include "viewport.h"
-#include "filefuncs.h"
+#include "pathfuncs.h"
 #include "shortcuts.h"
 
 static int context;
-static const char* selected_file = NULL;
+static const char *selected_file = NULL;
 static int selected_file_attr = 0;
 static int onplay_result = ONPLAY_OK;
-static char clipboard_selection[MAX_PATH];
-static int clipboard_selection_attr = 0;
-static bool clipboard_is_copy = false;
 
 /* redefine MAKE_MENU so the MENU_EXITAFTERTHISMENU flag can be added easily */
 #define MAKE_ONPLAYMENU( name, str, callback, icon, ... )               \
@@ -82,6 +79,63 @@ static bool clipboard_is_copy = false;
          MENU_ITEM_COUNT(sizeof( name##_)/sizeof(*name##_)),            \
             { (void*)name##_},{.callback_and_desc = & name##__}};
 
+/* Used for directory move, copy and delete */
+struct dirrecurse_params
+{
+    char path[MAX_PATH];    /* Buffer for full path */
+    size_t append;          /* Append position in 'path' for stack push */
+};
+
+enum clipboard_op_flags
+{
+    PASTE_CUT       = 0x00, /* Is a move (cut) operation (default) */
+    PASTE_COPY      = 0x01, /* Is a copy operation */
+    PASTE_OVERWRITE = 0x02, /* Overwrite destination */
+    PASTE_EXDEV     = 0x04, /* Actually copy/move across volumes */
+};
+
+/* result codec of various onplay operations */
+enum onplay_result_code
+{
+    /* Anything < 0 is failure */
+    OPRC_SUCCESS   = 0,     /* All operations completed successfully */
+    OPRC_NOOP      = 1,     /* Operation didn't need to do anything */
+    OPRC_CANCELLED = 2,     /* Operation was cancelled by user */
+    OPRC_NOOVERWRT = 3,
+};
+
+static struct clipboard
+{
+    char path[MAX_PATH];    /* Clipped file's path */
+    unsigned int attr;      /* Clipped file's attributes */
+    unsigned int flags;     /* Operation type flags */
+} clipboard;
+
+/* Empty the clipboard */
+static void clipboard_clear_selection(struct clipboard *clip)
+{
+    clip->path[0] = '\0';
+    clip->attr    = 0;
+    clip->flags   = 0;
+}
+
+/* Store the selection in the clipboard */
+static bool clipboard_clip(struct clipboard *clip, const char *path,
+                           unsigned int attr, unsigned int flags)
+{
+    /* if it fits it clips */
+    if (strlcpy(clip->path, path, sizeof (clip->path))
+            < sizeof (clip->path)) {
+        clip->attr = attr;
+        clip->flags = flags;
+        return true;
+    }
+    else {
+        clipboard_clear_selection(clip);
+        return false;
+    }
+}
+
 /* ----------------------------------------------------------------------- */
 /* Displays the bookmark menu options for the user to decide.  This is an  */
 /* interface function.                                                     */
@@ -492,438 +546,578 @@ static void draw_slider(void)
 #define draw_slider()
 #endif
 
-/* helper function to remove a non-empty directory */
-static int remove_dir(char* dirname, int len)
+static void clear_display(bool update)
 {
-    int result = 0;
-    DIR* dir;
-    int dirlen = strlen(dirname);
+    struct viewport vp;
 
-    dir = opendir(dirname);
-    if (!dir)
+    FOR_NB_SCREENS(i)
+    {
+        struct screen * screen = &screens[i];
+        viewport_set_defaults(&vp, screen->screen_type);
+        screen->set_viewport(&vp);
+        screen->clear_viewport();
+        if (update) {
+            screen->update_viewport();
+        }
+        screen->set_viewport(NULL);
+    }
+}
+
+static void splash_path(const char *path)
+{
+    clear_display(false);
+    path_basename(path, &path);
+    splash(0, path);
+    draw_slider();
+}
+
+/* Splashes the path and checks the keys */
+static bool poll_cancel_action(const char *path)
+{
+    splash_path(path);
+    return ACTION_STD_CANCEL == get_action(CONTEXT_STD, TIMEOUT_NOBLOCK);
+}
+
+static int confirm_overwrite(void)
+{
+    static const char *lines[] = { ID2P(LANG_REALLY_OVERWRITE) };
+    static const struct text_message message = { lines, 1 };
+    return gui_syncyesno_run(&message, NULL, NULL);
+}
+
+static int confirm_delete(const char *file)
+{
+    const char *lines[] = { ID2P(LANG_REALLY_DELETE), file };
+    const char *yes_lines[] = { ID2P(LANG_DELETING), file };
+    const struct text_message message = { lines, 2 };
+    const struct text_message yes_message = { yes_lines, 2 };
+    return gui_syncyesno_run(&message, &yes_message, NULL);
+}
+
+static bool check_new_name(const char *basename)
+{
+    /* at least prevent escapes out of the base directory from keyboard-
+       entered filenames; the file code should reject other invalidities */
+    return *basename != '\0' && !strchr(basename, PATH_SEPCH) &&
+           !is_dotdir_name(basename);
+}
+
+static void splash_cancelled(void)
+{
+    clear_display(true);
+    splash(HZ, ID2P(LANG_CANCEL));
+}
+
+static void splash_failed(int lang_what)
+{
+    cond_talk_ids_fq(lang_what, LANG_FAILED);
+    clear_display(true);
+    splashf(HZ*2, "%s %s", str(lang_what), str(LANG_FAILED));
+}
+
+/* helper function to remove a non-empty directory */
+static int remove_dir(struct dirrecurse_params *parm)
+{
+    DIR *dir = opendir(parm->path);
+    if (!dir) {
         return -1; /* open error */
+    }
 
-    while(true)
-    {
-        struct dirent* entry;
-        /* walk through the directory content */
-        entry = readdir(dir);
-        if (!entry)
+    size_t append = parm->append;
+    int rc = OPRC_SUCCESS;
+
+    /* walk through the directory content */
+    while (rc == OPRC_SUCCESS) {
+        errno = 0; /* distinguish failure from eod */
+        struct dirent *entry = readdir(dir);
+        if (!entry) {
+            if (errno) {
+                rc = -1;
+            }
             break;
+        }
+
         struct dirinfo info = dir_get_info(dir, entry);
-        dirname[dirlen] ='\0';
-        /* inform the user which dir we're deleting */
-        splash(0, dirname);
+        if ((info.attribute & ATTR_DIRECTORY) &&
+            is_dotdir_name(entry->d_name)) {
+            continue; /* skip these */
+        }
 
         /* append name to current directory */
-        snprintf(dirname+dirlen, len-dirlen, "/%s", entry->d_name);
-        if (info.attribute & ATTR_DIRECTORY)
-        {   /* remove a subdirectory */
-            if (!strcmp((char *)entry->d_name, ".") ||
-                !strcmp((char *)entry->d_name, ".."))
-                continue; /* skip these */
-
-            result = remove_dir(dirname, len); /* recursion */
-            if (result)
-                break; /* or better continue, delete what we can? */
-        }
-        else
-        {   /* remove a file */
-            draw_slider();
-            result = remove(dirname);
+        parm->append = append + path_append(&parm->path[append],
+                                            PA_SEP_HARD, entry->d_name,
+                                            sizeof (parm->path) - append);
+        if (parm->append >= sizeof (parm->path)) {
+            rc = -1;
+            break; /* no space left in buffer */
         }
-        if(ACTION_STD_CANCEL == get_action(CONTEXT_STD,TIMEOUT_NOBLOCK))
-        {
-            splash(HZ, ID2P(LANG_CANCEL));
-            result = -1;
-            break;
+
+        if (info.attribute & ATTR_DIRECTORY) {
+            /* remove a subdirectory */
+            rc = remove_dir(parm);
+        } else {
+            /* remove a file */
+            if (poll_cancel_action(parm->path)) {
+                rc = OPRC_CANCELLED;
+                break;
+            }
+
+            rc = remove(parm->path);
         }
+
+        /* Remove basename we added above */
+        parm->path[append] = '\0';
     }
-    closedir(dir);
 
-    if (!result)
-    {   /* remove the now empty directory */
-        dirname[dirlen] = '\0'; /* terminate to original length */
+    closedir(dir);
 
-        result = rmdir(dirname);
+    if (rc == 0) {
+        /* remove the now empty directory */
+        if (poll_cancel_action(parm->path)) {
+            rc = OPRC_CANCELLED;
+        } else {
+            rc = rmdir(parm->path);
+        }
     }
 
-    return result;
+    return rc;
 }
 
-
 /* share code for file and directory deletion, saves space */
-static bool delete_file_dir(void)
+static int delete_file_dir(void)
 {
-    char file_to_delete[MAX_PATH];
-    strcpy(file_to_delete, selected_file);
+    if (confirm_delete(selected_file) != YESNO_YES) {
+        return 1;
+    }
 
-    const char *lines[]={
-        ID2P(LANG_REALLY_DELETE),
-        file_to_delete
-    };
-    const char *yes_lines[]={
-        ID2P(LANG_DELETING),
-        file_to_delete
-    };
+    clear_display(true);
+    splash(HZ/2, str(LANG_DELETING));
 
-    const struct text_message message={lines, 2};
-    const struct text_message yes_message={yes_lines, 2};
+    int rc = -1;
 
-    if(gui_syncyesno_run(&message, &yes_message, NULL)!=YESNO_YES)
-        return false;
+    if (selected_file_attr & ATTR_DIRECTORY) { /* true if directory */
+        struct dirrecurse_params parm;
+        parm.append = strlcpy(parm.path, selected_file, sizeof (parm.path));
 
-    splash(0, str(LANG_DELETING));
+        if (parm.append < sizeof (parm.path)) {
+            cpu_boost(true);
+            rc = remove_dir(&parm);
+            cpu_boost(false);
+        }
+    } else {
+        rc = remove(selected_file);
+    }
 
-    int res;
-    if (selected_file_attr & ATTR_DIRECTORY) /* true if directory */
-    {
-        char pathname[MAX_PATH]; /* space to go deep */
-        cpu_boost(true);
-        strlcpy(pathname, file_to_delete, sizeof(pathname));
-        res = remove_dir(pathname, sizeof(pathname));
-        cpu_boost(false);
+    if (rc < OPRC_SUCCESS) {
+        splash_failed(LANG_DELETE);
+    } else if (rc == OPRC_CANCELLED) {
+        splash_cancelled();
     }
-    else
-        res = remove(file_to_delete);
 
-    if (!res)
+    if (rc != OPRC_NOOP) {
+        /* Could have failed after some but not all needed changes; reload */
         onplay_result = ONPLAY_RELOAD_DIR;
+    }
 
-    return (res == 0);
+    return 1;
 }
 
-static bool rename_file(void)
+static int rename_file(void)
 {
+    int rc = -1;
     char newname[MAX_PATH];
-    char* ptr = strrchr(selected_file, '/') + 1;
-    int pathlen = (ptr - selected_file);
-    strlcpy(newname, selected_file, sizeof(newname));
-    if (!kbd_input(newname + pathlen, (sizeof newname)-pathlen)) {
-        if (!strlen(newname + pathlen) ||
-            (rename(selected_file, newname) < 0)) {
-            cond_talk_ids_fq(LANG_RENAME, LANG_FAILED);
-            splashf(HZ*2, "%s %s", str(LANG_RENAME), str(LANG_FAILED));
+    const char *oldbase, *selection = selected_file;
+
+    path_basename(selection, &oldbase);
+    size_t pathlen = oldbase - selection;
+    char *newbase = newname + pathlen;
+
+    if (strlcpy(newname, selection, sizeof (newname)) >= sizeof (newname)) {
+        /* Too long */
+    } else if (kbd_input(newbase, sizeof (newname) - pathlen) < 0) {
+        rc = OPRC_CANCELLED;
+    } else if (!strcmp(oldbase, newbase)) {
+        rc = OPRC_NOOP; /* No change at all */
+    } else if (check_new_name(newbase)) {
+        switch (relate(selection, newname))
+        {
+        case RELATE_DIFFERENT:
+            if (file_exists(newname)) {
+                break; /* don't overwrite */
+            }
+            /* Fall-through */
+        case RELATE_SAME:
+            rc = rename(selection, newname);
+            break;
+        case RELATE_PREFIX:
+        default:
+            break;
         }
-        else
-            onplay_result = ONPLAY_RELOAD_DIR;
     }
 
-    return false;
+    if (rc < OPRC_SUCCESS) {
+        splash_failed(LANG_RENAME);
+    } else if (rc == OPRC_CANCELLED) {
+        /* splash_cancelled(); kbd_input() splashes it */
+    } else if (rc == OPRC_SUCCESS) {
+        onplay_result = ONPLAY_RELOAD_DIR;
+    }
+
+    return 1;
 }
 
-static bool create_dir(void)
+static int create_dir(void)
 {
+    int rc = -1;
     char dirname[MAX_PATH];
-    char *cwd;
-    int rc;
-    int pathlen;
-
-    cwd = getcwd(NULL, 0);
-    memset(dirname, 0, sizeof dirname);
-
-    snprintf(dirname, sizeof dirname, "%s/", cwd[1] ? cwd : "");
-
-    pathlen = strlen(dirname);
-    rc = kbd_input(dirname + pathlen, (sizeof dirname)-pathlen);
-    if (rc < 0)
-        return false;
+    size_t pathlen = path_append(dirname, getcwd(NULL, 0), PA_SEP_HARD,
+                                 sizeof (dirname));
+    char *basename = dirname + pathlen;
+
+    if (pathlen >= sizeof (dirname)) {
+        /* Too long */
+    } else if (kbd_input(basename, sizeof (dirname) - pathlen) < 0) {
+        rc = OPRC_CANCELLED;
+    } else if (check_new_name(basename)) {
+        rc = mkdir(dirname);
+    }
 
-    rc = mkdir(dirname);
-    if (rc < 0) {
-        cond_talk_ids_fq(LANG_CREATE_DIR, LANG_FAILED);
-        splashf(HZ, (unsigned char *)"%s %s", str(LANG_CREATE_DIR),
-                                              str(LANG_FAILED));
-    } else {
+    if (rc < OPRC_SUCCESS) {
+        splash_failed(LANG_CREATE_DIR);
+    } else if (rc == OPRC_CANCELLED) {
+        /* splash_cancelled(); kbd_input() splashes it */
+    } else if (rc == OPRC_SUCCESS) {
         onplay_result = ONPLAY_RELOAD_DIR;
     }
 
-    return true;
+    return 1;
 }
 
-/* Store the current selection in the clipboard */
-static bool clipboard_clip(bool copy)
+/* Paste a file */
+static int clipboard_pastefile(const char *src, const char *target,
+                               unsigned int flags)
 {
-    clipboard_selection[0] = 0;
-    strlcpy(clipboard_selection, selected_file, sizeof(clipboard_selection));
-    clipboard_selection_attr = selected_file_attr;
-    clipboard_is_copy = copy;
-
-    return true;
-}
+    int rc = -1;
+
+    while (!(flags & (PASTE_COPY | PASTE_EXDEV))) {
+        if ((flags & PASTE_OVERWRITE) || !file_exists(target)) {
+            /* Rename and possibly overwrite the file */
+            if (poll_cancel_action(src)) {
+                rc = OPRC_CANCELLED;
+            } else {
+                rc = rename(src, target);
+            }
 
-static bool clipboard_cut(void)
-{
-    return clipboard_clip(false);
-}
+        #ifdef HAVE_MULTIVOLUME
+            if (rc < 0 && errno == EXDEV) {
+                /* Failed because cross volume rename doesn't work; force
+                   a move instead */
+                flags |= PASTE_EXDEV;
+                break;
+            }
+        #endif /* HAVE_MULTIVOLUME */
+        }
 
-static bool clipboard_copy(void)
-{
-    return clipboard_clip(true);
-}
+        return rc;
+    }
 
-/* Paste a file to a new directory. Will overwrite always. */
-static bool clipboard_pastefile(const char *src, const char *target, bool copy)
-{
-    int src_fd, target_fd;
+    /* See if we can get the plugin buffer for the file copy buffer */
     size_t buffersize;
-    ssize_t size, bytesread, byteswritten;
-    char *buffer;
-    bool result = false;
-
-    if (copy) {
-        /* See if we can get the plugin buffer for the file copy buffer */
-        buffer = (char *) plugin_get_buffer(&buffersize);
-        if (buffer == NULL || buffersize < 512) {
-            /* Not large enough, try for a disk sector worth of stack
-               instead */
-            buffersize = 512;
-            buffer = (char *) __builtin_alloca(buffersize);
-        }
+    char *buffer = (char *) plugin_get_buffer(&buffersize);
+    if (buffer == NULL || buffersize < 512) {
+        /* Not large enough, try for a disk sector worth of stack
+           instead */
+        buffersize = 512;
+        buffer = (char *)alloca(buffersize);
+    }
 
-        if (buffer == NULL) {
-            return false;
-        }
+    if (buffer == NULL) {
+        return -1;
+    }
 
-        buffersize &= ~0x1ff;  /* Round buffer size to multiple of sector
-                                  size */
+    buffersize &= ~0x1ff;  /* Round buffer size to multiple of sector
+                              size */
 
-        src_fd = open(src, O_RDONLY);
+    int src_fd = open(src, O_RDONLY);
+    if (src_fd >= 0) {
+        int oflag = O_WRONLY|O_CREAT;
 
-        if (src_fd >= 0) {
-            target_fd = creat(target, 0666);
+        if (!(flags & PASTE_OVERWRITE)) {
+            oflag |= O_EXCL;
+        }
 
-            if (target_fd >= 0) {
-                result = true;
+        int target_fd = open(target, oflag, 0666);
+        if (target_fd >= 0) {
+            off_t total_size = 0;
+            off_t next_cancel_test = 0; /* No excessive button polling */
 
-                size = filesize(src_fd);
+            rc = OPRC_SUCCESS;
 
-                if (size == -1) {
-                    result = false;
+            while (rc == OPRC_SUCCESS) {
+                if (total_size >= next_cancel_test) {
+                    next_cancel_test = total_size + 0x10000;
+                    if (poll_cancel_action(src)) {
+                       rc = OPRC_CANCELLED;
+                       break;
+                    }
                 }
 
-                while(size > 0) {
-                    bytesread = read(src_fd, buffer, buffersize);
-
-                    if (bytesread == -1) {
-                        result = false;
-                        break;
+                ssize_t bytesread = read(src_fd, buffer, buffersize);
+                if (bytesread <= 0) {
+                    if (bytesread < 0) {
+                        rc = -1;
                     }
+                    /* else eof on buffer boundary; nothing to write */
+                    break;
+                }
 
-                    size -= bytesread;
-
-                    while(bytesread > 0) {
-                        byteswritten = write(target_fd, buffer, bytesread);
-
-                        if (byteswritten < 0) {
-                            result = false;
-                            size = 0;
-                            break;
-                        }
-
-                        bytesread -= byteswritten;
-                        draw_slider();
-                    }
+                ssize_t byteswritten = write(target_fd, buffer, bytesread);
+                if (byteswritten < bytesread) {
+                    /* Some I/O error */
+                    rc = -1;
+                    break;
                 }
 
-                close(target_fd);
+                total_size += byteswritten;
 
-                /* Copy failed. Cleanup. */
-                if (!result) {
-                    remove(target);
+                if (bytesread < (ssize_t)buffersize) {
+                    /* EOF with trailing bytes */
+                    break;
                 }
             }
 
-            close(src_fd);
-        }
-    } else {
-        result = rename(src, target) == 0;
-#ifdef HAVE_MULTIVOLUME
-        if (!result) {
-            if (errno == EXDEV) {
-                /* Failed because cross volume rename doesn't work. Copy
-                   instead */
-                result = clipboard_pastefile(src, target, true);
-
-                if (result) {
-                    result = remove(src) == 0;
-                }
+            if (rc == OPRC_SUCCESS) {
+                /* If overwriting, set the correct length if original was
+                   longer */
+                rc = ftruncate(target_fd, total_size);
+            }
+
+            close(target_fd);
+
+            if (rc != OPRC_SUCCESS) {
+                /* Copy failed. Cleanup. */
+                remove(target);
             }
         }
-#endif
+
+        close(src_fd);
     }
 
-    return result;
+    if (rc == OPRC_SUCCESS && !(flags & PASTE_COPY)) {
+        /* Remove the source file */
+        rc = remove(src);
+    }
+
+    return rc;
 }
 
-/* Paste a directory to a new location. Designed to be called by
-   clipboard_paste */
-static bool clipboard_pastedirectory(char *src, int srclen, char *target,
-                                     int targetlen, bool copy)
+/* Paste a directory */
+static int clipboard_pastedirectory(struct dirrecurse_params *src,
+                                    struct dirrecurse_params *target,
+                                    unsigned int flags)
 {
-    DIR *srcdir;
-    int srcdirlen = strlen(src);
-    int targetdirlen = strlen(target);
-    bool result = true;
-
-    if (!file_exists(target)) {
-        if (!copy) {
-            /* Just move the directory */
-            result = rename(src, target) == 0;
+    int rc = -1;
+
+    while (!(flags & (PASTE_COPY | PASTE_EXDEV))) {
+        if ((flags & PASTE_OVERWRITE) || !file_exists(target->path)) {
+            /* Just try to move the directory */
+            if (poll_cancel_action(src->path)) {
+                rc = OPRC_CANCELLED;
+            } else {
+                rc = rename(src->path, target->path);
+            }
 
-#ifdef HAVE_MULTIVOLUME
-            if (!result && errno == EXDEV) {
-                /* Try a copy as we're going across devices */
-                result = clipboard_pastedirectory(src, srclen, target,
-                    targetlen, true);
-
-                /* If it worked, remove the source directory */
-                if (result) {
-                    remove_dir(src, srclen);
+            if (rc < 0) {
+                int errnum = errno;
+                if (errnum == ENOTEMPTY && (flags & PASTE_OVERWRITE)) {
+                    /* Directory is not empty thus rename() will not do a quick
+                       overwrite */
+                    break;
                 }
+            #ifdef HAVE_MULTIVOLUME
+                else if (errnum == EXDEV) {
+                    /* Failed because cross volume rename doesn't work; force
+                       a move instead */
+                    flags |= PASTE_EXDEV;
+                    break;
+                }                
+            #endif /* HAVE_MULTIVOLUME */
             }
-#endif
-            return result;
-        } else {
-            /* Make a directory to copy things to */
-            result = mkdir(target) == 0;
         }
-    }
 
-    /* Check if something went wrong already */
-    if (!result) {
-        return result;
+        return rc;
     }
 
-    srcdir = opendir(src);
-    if (!srcdir) {
-        return false;
+    DIR *srcdir = opendir(src->path);
+
+    if (srcdir) {
+        /* Make a directory to copy things to */
+        rc = mkdir(target->path);
+        if (rc < 0 && errno == EEXIST && (flags & PASTE_OVERWRITE)) {
+            /* Exists and overwrite was approved */
+            rc = OPRC_SUCCESS;
+        }
     }
 
-    /* This loop will exit as soon as there's a problem */
-    while(result)
-    {
-        struct dirent* entry;
-        /* walk through the directory content */
-        entry = readdir(srcdir);
-        if (!entry)
+    size_t srcap = src->append, targetap = target->append;
+
+    /* Walk through the directory content; this loop will exit as soon as
+       there's a problem */
+    while (rc == OPRC_SUCCESS) {
+        errno = 0; /* Distinguish failure from eod */
+        struct dirent *entry = readdir(srcdir);
+        if (!entry) {
+            if (errno) {
+                rc = -1;
+            }
             break;
+        }
 
         struct dirinfo info = dir_get_info(srcdir, entry);
-        /* append name to current directory */
-        snprintf(src+srcdirlen, srclen-srcdirlen, "/%s", entry->d_name);
-        snprintf(target+targetdirlen, targetlen-targetdirlen, "/%s",
-            entry->d_name);
+        if ((info.attribute & ATTR_DIRECTORY) &&
+            is_dotdir_name(entry->d_name)) {
+            continue; /* Skip these */
+        }
 
-        DEBUGF("Copy %s to %s\n", src, target);
+        /* Append names to current directories */
+        src->append = srcap +
+            path_append(&src->path[srcap], PA_SEP_HARD, entry->d_name,
+                        sizeof(src->path) - srcap);
 
-        if (info.attribute & ATTR_DIRECTORY)
-        {   /* copy/move a subdirectory */
-            if (!strcmp((char *)entry->d_name, ".") ||
-                !strcmp((char *)entry->d_name, ".."))
-                continue; /* skip these */
+        target->append = targetap +
+            path_append(&target->path[targetap], PA_SEP_HARD, entry->d_name,
+                        sizeof (target->path) - targetap);
 
-            result = clipboard_pastedirectory(src, srclen, target, targetlen,
-                copy); /* recursion */
+        if (src->append >= sizeof (src->path) ||
+            target->append >= sizeof (target->path)) {
+            rc = -1; /* No space left in buffer */
+            break;
         }
-        else
-        {   /* copy/move a file */
-            draw_slider();
-            result = clipboard_pastefile(src, target, copy);
+
+        if (poll_cancel_action(src->path)) {
+            rc = OPRC_CANCELLED;
+            break;
+        }
+ 
+        DEBUGF("Copy %s to %s\n", src->path, target->path);
+
+        if (info.attribute & ATTR_DIRECTORY) {
+            /* Copy/move a subdirectory */
+            rc = clipboard_pastedirectory(src, target, flags); /* recursion */
+        } else {
+            /* Copy/move a file */
+            rc = clipboard_pastefile(src->path, target->path, flags);
         }
+
+        /* Remove basenames we added above */
+        src->path[srcap] = target->path[targetap] = '\0';
+    }
+
+    if (rc == OPRC_SUCCESS && !(flags & PASTE_COPY)) {
+        /* Remove the now empty directory */
+        rc = rmdir(src->path);
     }
 
     closedir(srcdir);
+    return rc;
+}
 
-    if (result) {
-        src[srcdirlen] = '\0'; /* terminate to original length */
-        target[targetdirlen] = '\0'; /* terminate to original length */
-    }
+static bool clipboard_cut(void)
+{
+    return clipboard_clip(&clipboard, selected_file, selected_file_attr,
+                          PASTE_CUT);
+}
 
-    return result;
+static bool clipboard_copy(void)
+{
+    return clipboard_clip(&clipboard, selected_file, selected_file_attr,
+                          PASTE_COPY);
 }
 
 /* Paste the clipboard to the current directory */
-static bool clipboard_paste(void)
+static int clipboard_paste(void)
 {
-    char target[MAX_PATH];
-    char *cwd, *nameptr;
-    bool success;
+    if (!clipboard.path[0])
+        return 1;
 
-    static const char *lines[]={ID2P(LANG_REALLY_OVERWRITE)};
-    static const struct text_message message={lines, 1};
+    int rc = -1;
 
-    /* Get the name of the current directory */
-    cwd = getcwd(NULL, 0);
+    struct dirrecurse_params src, target;
+    unsigned int flags = clipboard.flags;
 
     /* Figure out the name of the selection */
-    nameptr = strrchr(clipboard_selection, '/');
+    const char *nameptr;
+    path_basename(clipboard.path, &nameptr);
 
     /* Final target is current directory plus name of selection  */
-    snprintf(target, sizeof(target), "%s%s", cwd[1] ? cwd : "", nameptr);
-
-    /* If the target existed but they choose not to overwite, exit */
-    if (file_exists(target) &&
-        (gui_syncyesno_run(&message, NULL, NULL) == YESNO_NO)) {
-        return false;
-    }
+    target.append = path_append(target.path, getcwd(NULL, 0),
+                                nameptr, sizeof (target.path));
 
-    if (clipboard_is_copy) {
-        splash(0, ID2P(LANG_COPYING));
-    }
-    else
+    switch (target.append < sizeof (target.path) ?
+                relate(clipboard.path, target.path) : -1)
     {
-        splash(0, ID2P(LANG_MOVING));
-    }
+    case RELATE_SAME:
+        rc = OPRC_NOOP;
+        break;
+
+    case RELATE_DIFFERENT:
+        if (file_exists(target.path)) {
+            /* If user chooses not to overwrite, cancel */
+            if (confirm_overwrite() == YESNO_NO) {
+                rc = OPRC_NOOVERWRT;
+                break;
+            }
 
-    /* Now figure out what we're doing */
-    cpu_boost(true);
-    if (clipboard_selection_attr & ATTR_DIRECTORY) {
-        /* Recursion. Set up external stack */
-        char srcpath[MAX_PATH];
-        char targetpath[MAX_PATH];
-        if (!strncmp(clipboard_selection, target, strlen(clipboard_selection)))
-        {
-            /* Do not allow the user to paste a directory into a dir they are
-               copying */
-            success = 0;
+            flags |= PASTE_OVERWRITE;
         }
-        else
-        {
-            strlcpy(srcpath, clipboard_selection, sizeof(srcpath));
-            strlcpy(targetpath, target, sizeof(targetpath));
 
-            success = clipboard_pastedirectory(srcpath, sizeof(srcpath),
-                             target, sizeof(targetpath), clipboard_is_copy);
+        clear_display(true);
+        splash(HZ/2, (flags & PASTE_COPY) ? ID2P(LANG_COPYING) :
+                                            ID2P(LANG_MOVING));
 
-            if (success && !clipboard_is_copy)
-            {
-                strlcpy(srcpath, clipboard_selection, sizeof(srcpath));
-                remove_dir(srcpath, sizeof(srcpath));
+        /* Now figure out what we're doing */
+        cpu_boost(true);
+
+        if (clipboard.attr & ATTR_DIRECTORY) {
+            /* Copy or move a subdirectory */
+            src.append = strlcpy(src.path, clipboard.path,
+                                 sizeof (src.path));
+            if (src.append < sizeof (src.path)) {
+                rc = clipboard_pastedirectory(&src, &target, flags);
             }
+        } else {
+            /* Copy or move a file */
+            rc = clipboard_pastefile(clipboard.path, target.path, flags);
         }
-    } else {
-        success = clipboard_pastefile(clipboard_selection, target,
-            clipboard_is_copy);
+
+        cpu_boost(false);
+        break;
+
+    case RELATE_PREFIX:
+    default: /* Some other relation / failure */
+        break;
     }
-    cpu_boost(false);
 
-    /* Did it work? */
-    if (success) {
-        /* Reset everything */
-        clipboard_selection[0] = 0;
-        clipboard_selection_attr = 0;
-        clipboard_is_copy = false;
+    clear_display(true);
 
-        /* Force reload of the current directory */
+    switch (rc)
+    {
+    case OPRC_CANCELLED:
+        splash_cancelled();
+    case OPRC_SUCCESS:
         onplay_result = ONPLAY_RELOAD_DIR;
-    } else {
-        cond_talk_ids_fq(LANG_PASTE, LANG_FAILED);
-        splashf(HZ, (unsigned char *)"%s %s", str(LANG_PASTE),
-                                              str(LANG_FAILED));
+    case OPRC_NOOP:
+        clipboard_clear_selection(&clipboard);
+    case OPRC_NOOVERWRT:
+        break;
+    default:
+        if (rc < OPRC_SUCCESS) {
+            splash_failed(LANG_PASTE);
+            onplay_result = ONPLAY_RELOAD_DIR;
+        }
     }
 
-    return true;
+    return 1;
 }
 
 #ifdef HAVE_TAGCACHE
@@ -1094,15 +1288,12 @@ static int clipboard_callback(int action,const struct menu_item_ex *this_item)
     {
         case ACTION_REQUEST_MENUITEM:
 #ifdef HAVE_MULTIVOLUME
-            if ((selected_file_attr & FAT_ATTR_VOLUME) &&
-                (this_item == &rename_file_item ||
-                 this_item == &delete_dir_item ||
-                 this_item == &clipboard_cut_item) )
-                return ACTION_EXIT_MENUITEM;
             /* no rename+delete for volumes */
             if ((selected_file_attr & ATTR_VOLUME) &&
-                 (this_item == &delete_file_item ||
-                  this_item == &list_viewers_item))
+                (this_item == &rename_file_item ||
+                 this_item == &delete_dir_item ||
+                 this_item == &clipboard_cut_item ||
+                 this_item == &list_viewers_item))
                 return ACTION_EXIT_MENUITEM;
 #endif
 #ifdef HAVE_TAGCACHE
@@ -1117,7 +1308,7 @@ static int clipboard_callback(int action,const struct menu_item_ex *this_item)
 #endif
             if (this_item == &clipboard_paste_item)
             {  /* visible if there is something to paste */
-                return (clipboard_selection[0] != 0) ?
+                return (clipboard.path[0] != 0) ?
                                     action : ACTION_EXIT_MENUITEM;
             }
             else if (this_item == &create_dir_item)
@@ -1232,8 +1423,7 @@ static bool delete_item(void)
 {
 #ifdef HAVE_MULTIVOLUME
     /* no delete for volumes */
-    if ((selected_file_attr & FAT_ATTR_VOLUME) ||
-        (selected_file_attr & ATTR_VOLUME))
+    if (selected_file_attr & ATTR_VOLUME)
         return false;
 #endif
     return delete_file_dir();