Files
calcurse-edge/src/note.c
Lukas Fleischer 8d71923d4f Add a garbage collector for note files
Now that we use hashes to identify notes, a garbage collector comes in
handy. We search for note files that aren't referenced anywhere. Such
files might come up if a note, that isn't connected with any other item,
is edited.

Huge parts of this code are very hackish due to our data structure
layout and the way our hash table implementation works.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>
2011-10-05 12:25:47 +02:00

236 lines
5.7 KiB
C

/*
* Calcurse - text-based organizer
*
* Copyright (c) 2004-2011 calcurse Development Team <misc@calcurse.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* - 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 COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 COPYRIGHT
* OWNER OR CONTRIBUTORS 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.
*
* Send your feedback or comments to : misc@calcurse.org
* Calcurse home page : http://calcurse.org
*
*/
#include <unistd.h>
#include <dirent.h>
#include "calcurse.h"
#include "sha1.h"
struct note_gc_hash {
char *hash;
char buf[MAX_NOTESIZ + 1];
HTABLE_ENTRY (note_gc_hash);
};
/* Edit a note with an external editor. */
void
edit_note (char **note, char *editor)
{
char tmppath[BUFSIZ];
char *tmpext;
char notepath[BUFSIZ];
char *sha1 = mem_malloc (SHA1_DIGESTLEN * 2 + 1);
FILE *fp;
strncpy (tmppath, get_tempdir (), BUFSIZ);
strncat (tmppath, "/calcurse-note.", BUFSIZ);
if ((tmpext = new_tempfile (tmppath, TMPEXTSIZ)) == NULL)
return;
strncat (tmppath, tmpext, BUFSIZ);
mem_free (tmpext);
if (*note != NULL)
{
snprintf (notepath, BUFSIZ, "%s%s", path_notes, *note);
io_file_cp (notepath, tmppath);
}
wins_launch_external (tmppath, editor);
if (io_file_is_empty (tmppath) > 0)
erase_note (note);
else if ((fp = fopen (tmppath, "r")))
{
sha1_stream (fp, sha1);
fclose (fp);
*note = sha1;
snprintf (notepath, BUFSIZ, "%s%s", path_notes, *note);
io_file_cp (tmppath, notepath);
}
unlink (tmppath);
}
/* View a note in an external pager. */
void
view_note (char *note, char *pager)
{
char fullname[BUFSIZ];
if (note == NULL)
return;
(void)snprintf (fullname, BUFSIZ, "%s%s", path_notes, note);
wins_launch_external (fullname, pager);
}
/* Erase a note previously attached to an item. */
void
erase_note (char **note)
{
if (*note == NULL)
return;
mem_free (*note);
*note = NULL;
}
/* Read a serialized note file name from a stream and deserialize it. */
void
note_read (char *buffer, FILE *fp)
{
int i;
for (i = 0; i < MAX_NOTESIZ; i++)
{
buffer[i] = getc (fp);
if (buffer[i] == ' ')
{
buffer[i] = '\0';
return;
}
}
while (getc (fp) != ' ');
buffer[MAX_NOTESIZ] = '\0';
}
static void
note_gc_extract_key (struct note_gc_hash *data, char **key, int *len)
{
*key = data->hash;
*len = strlen (data->hash);
}
static int
note_gc_cmp (struct note_gc_hash *a, struct note_gc_hash *b)
{
return strcmp (a->hash, b->hash);
}
/* Spot and unlink unused note files. */
void
note_gc (void)
{
HTABLE_HEAD (htp, NOTE_GC_HSIZE, note_gc_hash) gc_htable =
HTABLE_INITIALIZER (&gc_htable);
struct note_gc_hash *hp;
DIR *dirp;
struct dirent *dp;
llist_item_t *i;
struct note_gc_hash tmph;
char notepath[BUFSIZ];
if (!(dirp = opendir (path_notes)))
return;
/* Insert all note file names into a hash table. */
HTABLE_GENERATE (htp, note_gc_hash, note_gc_extract_key, note_gc_cmp);
do
{
if ((dp = readdir (dirp)) && *(dp->d_name) != '.')
{
hp = mem_malloc (sizeof (struct note_gc_hash));
strncpy (hp->buf, dp->d_name, MAX_NOTESIZ + 1);
hp->hash = hp->buf;
HTABLE_INSERT (htp, &gc_htable, hp);
}
}
while (dp);
closedir (dirp);
/* Remove hashes that are actually in use. */
LLIST_TS_FOREACH (&alist_p, i)
{
struct apoint *apt = LLIST_GET_DATA (i);
if (apt->note)
{
tmph.hash = apt->note;
free (HTABLE_REMOVE (htp, &gc_htable, &tmph));
}
}
LLIST_FOREACH (&eventlist, i)
{
struct event *ev = LLIST_GET_DATA (i);
if (ev->note)
{
tmph.hash = ev->note;
free (HTABLE_REMOVE (htp, &gc_htable, &tmph));
}
}
LLIST_TS_FOREACH (&recur_alist_p, i)
{
struct recur_apoint *rapt = LLIST_GET_DATA (i);
if (rapt->note)
{
tmph.hash = rapt->note;
free (HTABLE_REMOVE (htp, &gc_htable, &tmph));
}
}
LLIST_FOREACH (&recur_elist, i)
{
struct recur_event *rev = LLIST_GET_DATA (i);
if (rev->note)
{
tmph.hash = rev->note;
free (HTABLE_REMOVE (htp, &gc_htable, &tmph));
}
}
LLIST_FOREACH (&todolist, i)
{
struct todo *todo = LLIST_GET_DATA (i);
if (todo->note)
{
tmph.hash = todo->note;
free (HTABLE_REMOVE (htp, &gc_htable, &tmph));
}
}
/* Unlink unused note files. */
HTABLE_FOREACH (hp, htp, &gc_htable)
{
snprintf (notepath, BUFSIZ, "%s%s", path_notes, hp->hash);
unlink (notepath);
}
}