path: root/e-util/e-path.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 8; tab-width: 8 -*- */
/* e-path.c
 *
 * Copyright (C) 2001 Ximian, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU 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.
 */

#include <config.h>

#include <sys/types.h>
#include <dirent.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
#include <glib.h>

#include "e-path.h"

#define SUBFOLDER_DIR_NAME     "subfolders"
#define SUBFOLDER_DIR_NAME_LEN 10

/**
 * e_path_to_physical:
 * @prefix: a prefix to prepend to the path, or %NULL
 * @path: the virtual path to convert to a filesystem path.
 *
 * This converts the "virtual" path @path into an expanded form that
 * allows a given name to refer to both a file and a directory. The
 * expanded path will have a "subfolders" directory inserted between
 * each path component. If the path ends with "/", the returned
 * physical path will end with "/subfolders"
 *
 * If @prefix is non-%NULL, it will be prepended to the returned path.
 *
 * Return value: the expanded path
 **/
char *
e_path_to_physical (const char *prefix, const char *vpath)
{
    const char *p, *newp;
    char *dp;
    char *ppath;
    int ppath_len;
    int prefix_len;

    while (*vpath == '/')
        vpath++;
    if (!prefix)
        prefix = "";

    /* Calculate the length of the real path. */
    ppath_len = strlen (vpath);
    ppath_len++;    /* For the ending zero.  */

    prefix_len = strlen (prefix);
    ppath_len += prefix_len;
    ppath_len++;    /* For the separating slash.  */

    /* Take account of the fact that we need to translate every
     * separator into `subfolders/'.
     */
    p = vpath;
    while (1) {
        newp = strchr (p, '/');
        if (newp == NULL)
            break;

        ppath_len += SUBFOLDER_DIR_NAME_LEN;
        ppath_len++; /* For the separating slash.  */

        /* Skip consecutive slashes.  */
        while (*newp == '/')
            newp++;

        p = newp;
    };

    ppath = g_malloc (ppath_len);
    dp = ppath;

    memcpy (dp, prefix, prefix_len);
    dp += prefix_len;
    *(dp++) = '/';

    /* Copy the mangled path.  */
    p = vpath;
    while (1) {
        newp = strchr (p, '/');
        if (newp == NULL) {
            strcpy (dp, p);
            break;
        }

        memcpy (dp, p, newp - p + 1); /* `+ 1' to copy the slash too.  */
        dp += newp - p + 1;

        memcpy (dp, SUBFOLDER_DIR_NAME, SUBFOLDER_DIR_NAME_LEN);
        dp += SUBFOLDER_DIR_NAME_LEN;

        *(dp++) = '/';

        /* Skip consecutive slashes.  */
        while (*newp == '/')
            newp++;

        p = newp;
    }

    return ppath;
}


static gboolean
find_folders_recursive (const char *physical_path, const char *path,
            EPathFindFoldersCallback callback, gpointer data)
{
    DIR *dir;
    char *subfolder_directory_path;
    gboolean ok;

    if (*path) {
        if (!callback (physical_path, path, data))
            return FALSE;

        subfolder_directory_path = g_strdup_printf ("%s/%s", physical_path, SUBFOLDER_DIR_NAME);
    } else {
        /* On the top level, we have no folders and,
         * consequently, no subfolder directory.
         */

        subfolder_directory_path = g_strdup (physical_path);
    }

    /* Now scan the subfolders and load them. */
    dir = opendir (subfolder_directory_path);
    if (dir == NULL) {
        g_free (subfolder_directory_path);
        return TRUE;
    }

    ok = TRUE;
    while (ok) {
        struct stat file_stat;
        struct dirent *dirent;
        char *file_path;
        char *new_path;

        dirent = readdir (dir);
        if (dirent == NULL)
            break;

        if (strcmp (dirent->d_name, ".") == 0 || strcmp (dirent->d_name, "..") == 0)
            continue;

        file_path = g_strdup_printf ("%s/%s", subfolder_directory_path,
                         dirent->d_name);

        if (stat (file_path, &file_stat) < 0 ||
            ! S_ISDIR (file_stat.st_mode)) {
            g_free (file_path);
            continue;
        }

        new_path = g_strdup_printf ("%s/%s", path, dirent->d_name);

        ok = find_folders_recursive (file_path, new_path, callback, data);

        g_free (file_path);
        g_free (new_path);
    }

    closedir (dir);
    g_free (subfolder_directory_path);

    return ok;
}

/**
 * e_path_find_folders:
 * @prefix: directory to start from
 * @callback: Callback to invoke on each folder
 * @data: Data for @callback
 *
 * Walks the folder tree starting at @prefix and calls @callback
 * on each folder.
 *
 * Return value: %TRUE on success, %FALSE if an error occurs at any point
 **/
gboolean
e_path_find_folders (const char *prefix,
             EPathFindFoldersCallback callback,
             gpointer data)
{
    return find_folders_recursive (prefix, "", callback, data);
}


/**
 * e_path_rmdir:
 * @prefix: a prefix to prepend to the path, or %NULL
 * @path: the virtual path to convert to a filesystem path.
 *
 * This removes the directory pointed to by @prefix and @path
 * and attempts to remove its parent "subfolders" directory too
 * if it's empty.
 *
 * Return value: -1 (with errno set) if it failed to rmdir the
 * specified directory. 0 otherwise, whether or not it removed
 * the parent directory.
 **/
int
e_path_rmdir (const char *prefix, const char *vpath)
{
    char *physical_path, *p;

    /* Remove the directory itself */
    physical_path = e_path_to_physical (prefix, vpath);
    if (rmdir (physical_path) == -1) {
        g_free (physical_path);
        return -1;
    }

    /* Attempt to remove its parent "subfolders" directory,
     * ignoring errors since it might not be empty.
     */

    p = strrchr (physical_path, '/');
    if (p[1] == '\0') {
        g_free (physical_path);
        return 0;
    }
    *p = '\0';
    p = strrchr (physical_path, '/');
    if (!p || strcmp (p + 1, SUBFOLDER_DIR_NAME) != 0) {
        g_free (physical_path);
        return 0;
    }

    rmdir (physical_path);
    g_free (physical_path);
    return 0;
}