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

/*
 * e-signature-utils.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) version 3.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with the program; if not, see <http://www.gnu.org/licenses/>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 */

#include "e-signature-utils.h"

#include <errno.h>
#include <camel/camel.h>
#include <glib/gstdio.h>
#include <gconf/gconf-client.h>

#ifndef G_OS_WIN32
#include <sys/wait.h>
#endif

#include "e-util/e-util.h"

static ESignatureList *global_signature_list;

ESignatureList *
e_get_signature_list (void)
{
    if (G_UNLIKELY (global_signature_list == NULL)) {
        GConfClient *client;

        client = gconf_client_get_default ();
        global_signature_list = e_signature_list_new (client);
        g_object_unref (client);
    }

    g_return_val_if_fail (global_signature_list != NULL, NULL);

    return global_signature_list;
}

ESignature *
e_get_signature_by_name (const gchar *name)
{
    ESignatureList *signature_list;
    const ESignature *signature;
    e_signature_find_t find;

    g_return_val_if_fail (name != NULL, NULL);

    find = E_SIGNATURE_FIND_NAME;
    signature_list = e_get_signature_list ();
    signature = e_signature_list_find (signature_list, find, name);

    /* XXX ESignatureList misuses const. */
    return (ESignature *) signature;
}

ESignature *
e_get_signature_by_uid (const gchar *uid)
{
    ESignatureList *signature_list;
    const ESignature *signature;
    e_signature_find_t find;

    g_return_val_if_fail (uid != NULL, NULL);

    find = E_SIGNATURE_FIND_UID;
    signature_list = e_get_signature_list ();
    signature = e_signature_list_find (signature_list, find, uid);

    /* XXX ESignatureList misuses const. */
    return (ESignature *) signature;
}

gchar *
e_create_signature_file (GError **error)
{
    const gchar *data_dir;
    gchar basename[32];
    gchar *filename;
    gchar *pathname;
    gint32 ii;

    data_dir = e_get_user_data_dir ();
    pathname = g_build_filename (data_dir, "signatures", NULL);
    filename = NULL;

    if (g_mkdir_with_parents (pathname, 0700) < 0) {
        g_set_error (
            error, G_FILE_ERROR,
            g_file_error_from_errno (errno),
            "%s: %s", pathname, g_strerror (errno));
        g_free (pathname);
        return NULL;
    }

    for (ii = 0; ii < G_MAXINT32; ii++) {

        g_snprintf (
            basename, sizeof (basename),
            "signature-%" G_GINT32_FORMAT, ii);

        g_free (filename);
        filename = g_build_filename (pathname, basename, NULL);

        if (!g_file_test (filename, G_FILE_TEST_EXISTS)) {
            gint fd;

            fd = g_creat (filename, 0600);
            if (fd >= 0) {
                close (fd);
                break;
            }

            /* If we failed once we're probably going
             * to continue failing, so just give up. */
            g_set_error (
                error, G_FILE_ERROR,
                g_file_error_from_errno (errno),
                "%s: %s", filename, g_strerror (errno));
            g_free (filename);
            filename = NULL;
            break;
        }
    }

    /* If there are actually G_MAXINT32 signature files, the
     * most recent signature file we be overwritten.  Sorry. */

    return filename;
}

gchar *
e_read_signature_file (ESignature *signature,
                       gboolean convert_to_html,
                       GError **error)
{
    CamelStream *input_stream;
    CamelStream *output_stream;
    GByteArray *buffer;
    const gchar *filename;
    gboolean is_html;
    gchar *content;
    gsize length;
    gint fd;

    g_return_val_if_fail (E_IS_SIGNATURE (signature), NULL);

    filename = e_signature_get_filename (signature);
    is_html = e_signature_get_is_html (signature);

    fd = g_open (filename, O_RDONLY, 0);
    if (fd < 0) {
        g_set_error (
            error, G_FILE_ERROR,
            g_file_error_from_errno (errno),
            "%s: %s", filename, g_strerror (errno));
        return NULL;
    }

    input_stream = camel_stream_fs_new_with_fd (fd);

    if (!is_html && convert_to_html) {
        CamelStream *filtered_stream;
        CamelMimeFilter *filter;
        gint32 flags;

        filtered_stream =
            camel_stream_filter_new (input_stream);
        camel_object_unref (input_stream);

        flags =
            CAMEL_MIME_FILTER_TOHTML_PRESERVE_8BIT |
            CAMEL_MIME_FILTER_TOHTML_CONVERT_URLS |
            CAMEL_MIME_FILTER_TOHTML_CONVERT_ADDRESSES |
            CAMEL_MIME_FILTER_TOHTML_CONVERT_SPACES;
        filter = camel_mime_filter_tohtml_new (flags, 0);
        camel_stream_filter_add (
            CAMEL_STREAM_FILTER (filtered_stream), filter);
        camel_object_unref (filter);

        input_stream = filtered_stream;
    }

    buffer = g_byte_array_new ();
    output_stream = camel_stream_mem_new ();
    camel_stream_mem_set_byte_array (
        CAMEL_STREAM_MEM (output_stream), buffer);
    camel_stream_write_to_stream (input_stream, output_stream);
    camel_object_unref (output_stream);
    camel_object_unref (input_stream);

    /* Make sure the buffer is nul-terminated. */
    length = (gsize) buffer->len;
    g_byte_array_append (buffer, (guint8 *) "", 1);
    content = (gchar *) g_byte_array_free (buffer, FALSE);

    /* Signatures are saved as UTF-8, but we still need to check that
     * the signature is valid UTF-8 because the user may be opening
     * a signature file that is in his/her locale character set.  If
     * it's not in UTF-8 then try converting from the current locale. */
    if (!g_utf8_validate (content, length, NULL)) {
        gchar *utf8;

        utf8 = g_locale_to_utf8 (content, length, NULL, NULL, error);
        g_free (content);
        content = utf8;
    }

    return content;
}

gchar *
e_run_signature_script (const gchar *filename)
{
    /* FIXME Make this cross-platform, prefer GLib functions over
     *       POSIX, and report errors via GError instead of dumping
     *       messages to the terminal where users won't see them. */

#ifndef G_OS_WIN32
    gint in_fds[2];
    pid_t pid;

    g_return_val_if_fail (filename != NULL, NULL);

    if (pipe (in_fds) == -1) {
        g_warning (
            "Failed to create pipe to '%s': %s",
            filename, g_strerror (errno));
        return NULL;
    }

    pid = fork ();

    /* Child Process */
    if (pid == 0) {
        gint maxfd, ii;

        close (in_fds[0]);
        if (dup2 (in_fds[1], STDOUT_FILENO) < 0)
            _exit (255);
        close (in_fds[1]);

        setsid ();

        maxfd = sysconf (_SC_OPEN_MAX);
        for (ii = 3; ii < maxfd; ii++) {
            if (ii == STDIN_FILENO)
                continue;
            if (ii == STDOUT_FILENO)
                continue;
            if (ii == STDERR_FILENO)
                continue;
            fcntl (ii, F_SETFD, FD_CLOEXEC);
        }

        execlp ("/bin/sh", "/bin/sh", "-c", filename, NULL);

        g_warning (
            "Could not execute '%s': %s",
            filename, g_strerror (errno));

        _exit (255);

    /* Parent Process */
    } else if (pid > 0) {
        CamelStream *output_stream;
        CamelStream *input_stream;
        GByteArray *buffer;
        gchar *content;
        gsize length;
        gint result;
        gint status;

        close (in_fds[1]);

        buffer = g_byte_array_new ();
        output_stream = camel_stream_mem_new ();
        camel_stream_mem_set_byte_array (
            CAMEL_STREAM_MEM (output_stream), buffer);

        input_stream = camel_stream_fs_new_with_fd (in_fds[0]);
        camel_stream_write_to_stream (input_stream, output_stream);
        camel_object_unref (input_stream);

        camel_object_unref (output_stream);

        /* Make sure the buffer is nul-terminated. */
        length = (gsize) buffer->len;
        g_byte_array_append (buffer, (guchar *) "", 1);
        content = (gchar *) g_byte_array_free (buffer, FALSE);

        /* Signature scripts are supposed to generate UTF-8 content,
         * but because users are known to never read the manual, we
         * try to do our best if the content isn't valid UTF-8 by
         * assuming that the content is in the user's locale
         * character set. */
        if (!g_utf8_validate (content, length, NULL)) {
            gchar *utf8;

            /* XXX Should pass a GError here. */
            utf8 = g_locale_to_utf8 (
                content, length, NULL, NULL, NULL);
            g_free (content);
            content = utf8;
        }

        /* Wait for the script process to terminate. */
        result = waitpid (pid, &status, 0);

        if (result == -1 && errno == EINTR) {
            /* Child process is hanging... */
            kill (pid, SIGTERM);
            sleep (1);
            result = waitpid (pid, &status, WNOHANG);
            if (result == 0) {
                /* ...still hanging, set phasers to KILL. */
                kill (pid, SIGKILL);
                sleep (1);
                waitpid (pid, &status, WNOHANG);
            }
        }

        return content;

    /* Forking Failed */
    } else {
        g_warning (
            "Failed to create child process '%s': %s",
            filename, g_strerror (errno));
        close (in_fds[0]);
        close (in_fds[1]);
    }
#endif

    return NULL;
}