path: root/e-util/e-util.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/>  
 *
 *
 * Authors:
 *      Chris Lahey <clahey@ximian.com>
 *
 * Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
 *
 */

#include <config.h>

#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <ctype.h>
#include <math.h>
#include <string.h>
#include <locale.h>
#include <time.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <gio/gio.h>
#include <gtk/gtk.h>
#include <glib/gi18n.h>
#include <glib/gstdio.h>
#include <libgnome/gnome-init.h>

#ifdef G_OS_WIN32
#include <windows.h>
#endif

#include <libedataserver/e-data-server-util.h>
#include <libedataserver/e-categories.h>
#include "filter/filter-option.h"
#include "e-util.h"
#include "e-util-private.h"

/**
 * e_get_user_data_dir:
 *
 * Returns the base directory for Evolution-specific user data.
 * The string is owned by Evolution and must not be modified or freed.
 *
 * Returns: base directory for user data
 **/
const gchar *
e_get_user_data_dir (void)
{
    static gchar *dirname = NULL;

    if (G_UNLIKELY (dirname == NULL))
        dirname = g_build_filename (
            g_get_home_dir (), ".evolution", NULL);

    return dirname;
}

/**
 * e_get_accels_filename:
 *
 * Returns the name of the user data file containing custom keyboard
 * accelerator specifications.
 *
 * Returns: filename for accelerator specifications
 **/
const gchar *
e_get_accels_filename (void)
{
    static gchar *filename = NULL;

    if (G_UNLIKELY (filename == NULL))
        filename = g_build_filename (
            gnome_user_dir_get (),
            "accels", PACKAGE, NULL);

    return filename;
}

/**
 * e_show_uri:
 * @parent: a parent #GtkWindow or %NULL
 * @uri: the URI to show
 *
 * Launches the default application to show the given URI.  The URI must
 * be of a form understood by GIO.  If the URI cannot be shown, it presents
 * a dialog describing the error.  The dialog is set as transient to @parent
 * if @parent is non-%NULL.
 **/
void
e_show_uri (GtkWindow *parent,
            const gchar *uri)
{
    GtkWidget *dialog;
    GdkScreen *screen = NULL;
    GError *error = NULL;
    guint32 timestamp;

    g_return_if_fail (uri != NULL);

    timestamp = gtk_get_current_event_time ();

    if (parent != NULL)
        screen = gtk_widget_get_screen (GTK_WIDGET (parent));

    if (gtk_show_uri (screen, uri, timestamp, &error))
        return;

    dialog = gtk_message_dialog_new_with_markup (
        parent, GTK_DIALOG_DESTROY_WITH_PARENT,
        GTK_MESSAGE_ERROR, GTK_BUTTONS_OK,
        "<big><b>%s</b></big>",
        _("Could not open the link."));

    gtk_message_dialog_format_secondary_text (
        GTK_MESSAGE_DIALOG (dialog), "%s", error->message);

    gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);
    g_error_free (error);
}

/**
 * e_display_help:
 * @parent: a parent #GtkWindow or %NULL
 * @link_id: help section to present or %NULL
 *
 * Opens the user documentation to the section given by @link_id, or to the
 * table of contents if @link_id is %NULL.  If the user documentation cannot
 * be opened, it presents a dialog describing the error.  The dialog is set
 * as transient to @parent if @parent is non-%NULL.
 **/
void
e_display_help (GtkWindow *parent,
                const gchar *link_id)
{
    GString *uri;
    GtkWidget *dialog;
    GdkScreen *screen = NULL;
    GError *error = NULL;
    guint32 timestamp;

    uri = g_string_new ("ghelp:" PACKAGE);
    timestamp = gtk_get_current_event_time ();

    if (parent != NULL)
        screen = gtk_widget_get_screen (GTK_WIDGET (parent));

    if (link_id != NULL)
        g_string_append_printf (uri, "?%s", link_id);

    if (gtk_show_uri (screen, uri->str, timestamp, &error))
        goto exit;

    dialog = gtk_message_dialog_new_with_markup (
        parent, GTK_DIALOG_DESTROY_WITH_PARENT,
        GTK_MESSAGE_ERROR, GTK_BUTTONS_OK,
        "<big><b>%s</b></big>",
        _("Could not display help for Evolution."));

    gtk_message_dialog_format_secondary_text (
        GTK_MESSAGE_DIALOG (dialog), "%s", error->message);

    gtk_dialog_run (GTK_DIALOG (dialog));

    gtk_widget_destroy (dialog);
    g_error_free (error);

exit:
    g_string_free (uri, TRUE);
}

/**
 * e_str_without_underscores:
 * @s: the string to strip underscores from.
 *
 * Strips underscores from a string in the same way @gtk_label_new_with_mnemonis does.
 * The returned string should be freed.
 */
char *
e_str_without_underscores (const char *s)
{
    char *new_string;
    const char *sp;
    char *dp;

    new_string = g_malloc (strlen (s) + 1);

    dp = new_string;
    for (sp = s; *sp != '\0'; sp ++) {
        if (*sp != '_') {
            *dp = *sp;
            dp ++;
        } else if (sp[1] == '_') {
            /* Translate "__" in "_".  */
            *dp = '_';
            dp ++;
            sp ++;
        }
    }
    *dp = 0;

    return new_string;
}

gint
e_str_compare (gconstpointer x, gconstpointer y)
{
    if (x == NULL || y == NULL) {
        if (x == y)
            return 0;
        else
            return x ? -1 : 1;
    }

    return strcmp (x, y);
}

gint
e_str_case_compare (gconstpointer x, gconstpointer y)
{
    gchar *cx, *cy;
    gint res;

    if (x == NULL || y == NULL) {
        if (x == y)
            return 0;
        else
            return x ? -1 : 1;
    }

    cx = g_utf8_casefold (x, -1);
    cy = g_utf8_casefold (y, -1);

    res = g_utf8_collate (cx, cy);

    g_free (cx);
    g_free (cy);

    return res;
}

gint
e_collate_compare (gconstpointer x, gconstpointer y)
{
    if (x == NULL || y == NULL) {
        if (x == y)
            return 0;
        else
            return x ? -1 : 1;
    }

    return g_utf8_collate (x, y);
}

gint
e_int_compare (gconstpointer x, gconstpointer y)
{
    gint nx = GPOINTER_TO_INT (x);
    gint ny = GPOINTER_TO_INT (y);

    return (nx == ny) ? 0 : (nx < ny) ? -1 : 1;
}

gboolean
e_write_file_uri (const gchar *filename, const gchar *data)
{
    gboolean res;
    gsize length;
    GFile *file;
    GOutputStream *stream;
    GError *error = NULL;

    g_return_val_if_fail (filename != NULL, FALSE);
    g_return_val_if_fail (data != NULL, FALSE);

    length = strlen (data);

    /* if it is uri, then create file for uri, otherwise for path */
    if (strstr (filename, "://"))
        file = g_file_new_for_uri (filename);
    else
        file = g_file_new_for_path (filename);

    if (!file) {
        g_warning ("Couldn't save item");
        return FALSE;
    }

    stream = G_OUTPUT_STREAM (g_file_replace (file, NULL, FALSE, G_FILE_CREATE_NONE, NULL, &error));
    g_object_unref (file);

    if (!stream || error) {
        g_warning ("Couldn't save item%s%s", error ? ": " : "", error ? error->message : "");

        if (stream)
            g_object_unref (stream);

        if (error)
            g_error_free (error);

        return FALSE;
    }

    res = g_output_stream_write_all (stream, data, length, NULL, NULL, &error);

    if (error) {
        g_warning ("Couldn't save item: %s", error->message);
        g_clear_error (&error);
    }

    g_output_stream_close (stream, NULL, &error);
    g_object_unref (stream);

    if (error) {
        g_warning ("Couldn't close output stream: %s", error->message);
        g_error_free (error);
    }

    return res;
}

/* Include build marshalers */

#include "e-util-marshal.h"

static gint
epow10 (gint number)
{
    gint value = 1;

    while (number-- > 0)
        value *= 10;

    return value;
}

gchar *
e_format_number (gint number)
{
    GList *iterator, *list = NULL;
    struct lconv *locality;
    gint char_length = 0;
    gint group_count = 0;
    gchar *grouping;
    gint last_count = 3;
    gint divider;
    gchar *value;
    gchar *value_iterator;

    locality = localeconv();
    grouping = locality->grouping;
    while (number) {
        gchar *group;
        switch (*grouping) {
        default:
            last_count = *grouping;
            grouping++;
        case 0:
            divider = epow10(last_count);
            if (number >= divider) {
                group = g_strdup_printf("%0*d", last_count, number % divider);
            } else {
                group = g_strdup_printf("%d", number % divider);
            }
            number /= divider;
            break;
        case CHAR_MAX:
            group = g_strdup_printf("%d", number);
            number = 0;
            break;
        }
        char_length += strlen(group);
        list = g_list_prepend(list, group);
        group_count ++;
    }

    if (list) {
        value = g_new(gchar, 1 + char_length + (group_count - 1) * strlen(locality->thousands_sep));

        iterator = list;
        value_iterator = value;

        strcpy(value_iterator, iterator->data);
        value_iterator += strlen(iterator->data);
        for (iterator = iterator->next; iterator; iterator = iterator->next) {
            strcpy(value_iterator, locality->thousands_sep);
            value_iterator += strlen(locality->thousands_sep);

            strcpy(value_iterator, iterator->data);
            value_iterator += strlen(iterator->data);
        }
        g_list_foreach (list, (GFunc) g_free, NULL);
        g_list_free (list);
        return value;
    } else {
        return g_strdup("0");
    }
}

/* Perform a binary search for key in base which has nmemb elements
   of size bytes each.  The comparisons are done by (*compare)().  */
void
e_bsearch (gconstpointer key,
           gconstpointer base,
           gsize nmemb,
           gsize size,
       ESortCompareFunc compare,
           gpointer closure,
           gsize *start,
           gsize *end)
{
    gsize l, u, idx;
    gconstpointer p;
    gint comparison;
    if (!(start || end))
        return;

    l = 0;
    u = nmemb;
    while (l < u) {
        idx = (l + u) / 2;
        p = (((const gchar *) base) + (idx * size));
        comparison = (*compare) (key, p, closure);
        if (comparison < 0)
            u = idx;
        else if (comparison > 0)
            l = idx + 1;
        else {
            gsize lsave, usave;
            lsave = l;
            usave = u;
            if (start) {
                while (l < u) {
                    idx = (l + u) / 2;
                    p = (((const gchar *) base) + (idx * size));
                    comparison = (*compare) (key, p, closure);
                    if (comparison <= 0)
                        u = idx;
                    else
                        l = idx + 1;
                }
                *start = l;

                l = lsave;
                u = usave;
            }
            if (end) {
                while (l < u) {
                    idx = (l + u) / 2;
                    p = (((const gchar *) base) + (idx * size));
                    comparison = (*compare) (key, p, closure);
                    if (comparison < 0)
                        u = idx;
                    else
                        l = idx + 1;
                }
                *end = l;
            }
            return;
        }
    }

    if (start)
        *start = l;
    if (end)
        *end = l;
}

/**
 * Function to do a last minute fixup of the AM/PM stuff if the locale
 * and gettext haven't done it right. Most English speaking countries
 * except the USA use the 24 hour clock (UK, Australia etc). However
 * since they are English nobody bothers to write a language
 * translation (gettext) file. So the locale turns off the AM/PM, but
 * gettext does not turn on the 24 hour clock. Leaving a mess.
 *
 * This routine checks if AM/PM are defined in the locale, if not it
 * forces the use of the 24 hour clock.
 *
 * The function itself is a front end on strftime and takes exactly
 * the same arguments.
 *
 * TODO: Actually remove the '%p' from the fixed up string so that
 * there isn't a stray space.
 **/

gsize
e_strftime_fix_am_pm (gchar *str, gsize max, const gchar *fmt,
                      const struct tm *tm)
{
    gchar buf[10];
    gchar *sp;
    gchar *ffmt;
    gsize ret;

    if (strstr(fmt, "%p")==NULL && strstr(fmt, "%P")==NULL) {
        /* No AM/PM involved - can use the fmt string directly */
        ret=e_strftime(str, max, fmt, tm);
    } else {
        /* Get the AM/PM symbol from the locale */
        e_strftime (buf, 10, "%p", tm);

        if (buf[0]) {
            /**
             * AM/PM have been defined in the locale
             * so we can use the fmt string directly
             **/
            ret=e_strftime(str, max, fmt, tm);
        } else {
            /**
             * No AM/PM defined by locale
             * must change to 24 hour clock
             **/
            ffmt=g_strdup(fmt);
            for (sp=ffmt; (sp=strstr(sp, "%l")); sp++) {
                /**
                 * Maybe this should be 'k', but I have never
                 * seen a 24 clock actually use that format
                 **/
                sp[1]='H';
            }
            for (sp=ffmt; (sp=strstr(sp, "%I")); sp++) {
                sp[1]='H';
            }
            ret=e_strftime(str, max, ffmt, tm);
            g_free(ffmt);
        }
    }

    return(ret);
}

gsize
e_utf8_strftime_fix_am_pm (gchar *str, gsize max, const gchar *fmt,
                           const struct tm *tm)
{
    gsize sz, ret;
    gchar *locale_fmt, *buf;

    locale_fmt = g_locale_from_utf8(fmt, -1, NULL, &sz, NULL);
    if (!locale_fmt)
        return 0;

    ret = e_strftime_fix_am_pm(str, max, locale_fmt, tm);
    if (!ret) {
        g_free (locale_fmt);
        return 0;
    }

    buf = g_locale_to_utf8(str, ret, NULL, &sz, NULL);
    if (!buf) {
        g_free (locale_fmt);
        return 0;
    }

    if (sz >= max) {
        gchar *tmp = buf + max - 1;
        tmp = g_utf8_find_prev_char(buf, tmp);
        if (tmp)
            sz = tmp - buf;
        else
            sz = 0;
    }
    memcpy(str, buf, sz);
    str[sz] = '\0';
    g_free(locale_fmt);
    g_free(buf);
    return sz;
}

/**
 * e_get_month_name:
 * @month: month index
 * @abbreviated: if %TRUE, abbreviate the month name
 *
 * Returns the localized name for @month.  If @abbreviated is %TRUE,
 * returns the locale's abbreviated month name.
 *
 * Returns: localized month name
 **/
const gchar *
e_get_month_name (GDateMonth month,
                  gboolean abbreviated)
{
    /* Make the indices correspond to the enum values. */
    static const gchar *abbr_names[G_DATE_DECEMBER + 1];
    static const gchar *full_names[G_DATE_DECEMBER + 1];
    static gboolean first_time = TRUE;

    g_return_val_if_fail (month >= G_DATE_JANUARY, NULL);
    g_return_val_if_fail (month <= G_DATE_DECEMBER, NULL);

    if (G_UNLIKELY (first_time)) {
        gchar buffer[256];
        GDateMonth ii;
        GDate date;

        memset (abbr_names, 0, sizeof (abbr_names));
        memset (full_names, 0, sizeof (full_names));

        /* First Julian day was in January. */
        g_date_set_julian (&date, 1);

        for (ii = G_DATE_JANUARY; ii <= G_DATE_DECEMBER; ii++) {
            g_date_strftime (buffer, sizeof (buffer), "%b", &date);
            abbr_names[ii] = g_intern_string (buffer);
            g_date_strftime (buffer, sizeof (buffer), "%B", &date);
            full_names[ii] = g_intern_string (buffer);
            g_date_add_months (&date, 1);
        }

        first_time = FALSE;
    }

    return abbreviated ? abbr_names[month] : full_names[month];
}

/**
 * e_get_weekday_name:
 * @weekday: weekday index
 * @abbreviated: if %TRUE, abbreviate the weekday name
 *
 * Returns the localized name for @weekday.  If @abbreviated is %TRUE,
 * returns the locale's abbreviated weekday name.
 *
 * Returns: localized weekday name
 **/
const gchar *
e_get_weekday_name (GDateWeekday weekday,
                    gboolean abbreviated)
{
    /* Make the indices correspond to the enum values. */
    static const gchar *abbr_names[G_DATE_SUNDAY + 1];
    static const gchar *full_names[G_DATE_SUNDAY + 1];
    static gboolean first_time = TRUE;

    g_return_val_if_fail (weekday >= G_DATE_MONDAY, NULL);
    g_return_val_if_fail (weekday <= G_DATE_SUNDAY, NULL);

    if (G_UNLIKELY (first_time)) {
        gchar buffer[256];
        GDateWeekday ii;
        GDate date;

        memset (abbr_names, 0, sizeof (abbr_names));
        memset (full_names, 0, sizeof (full_names));

        /* First Julian day was a Monday. */
        g_date_set_julian (&date, 1);

        for (ii = G_DATE_MONDAY; ii <= G_DATE_SUNDAY; ii++) {
            g_date_strftime (buffer, sizeof (buffer), "%a", &date);
            abbr_names[ii] = g_intern_string (buffer);
            g_date_strftime (buffer, sizeof (buffer), "%A", &date);
            full_names[ii] = g_intern_string (buffer);
            g_date_add_days (&date, 1);
        }

        first_time = FALSE;
    }

    return abbreviated ? abbr_names[weekday] : full_names[weekday];
}

/**
 * e_flexible_strtod:
 * @nptr:    the string to convert to a numeric value.
 * @endptr:  if non-NULL, it returns the character after
 *           the last character used in the conversion.
 *
 * Converts a string to a gdouble value.  This function detects
 * strings either in the standard C locale or in the current locale.
 *
 * This function is typically used when reading configuration files or
 * other non-user input that should not be locale dependent, but may
 * have been in the past.  To handle input from the user you should
 * normally use the locale-sensitive system strtod function.
 *
 * To convert from a double to a string in a locale-insensitive way, use
 * @g_ascii_dtostr.
 *
 * Return value: the gdouble value.
 **/
gdouble
e_flexible_strtod (const gchar *nptr, gchar **endptr)
{
    gchar *fail_pos;
    gdouble val;
    struct lconv *locale_data;
    const gchar *decimal_point;
    gint decimal_point_len;
    const gchar *p, *decimal_point_pos;
    const gchar *end = NULL; /* Silence gcc */
    gchar *copy, *c;

    g_return_val_if_fail (nptr != NULL, 0);

    fail_pos = NULL;

    locale_data = localeconv ();
    decimal_point = locale_data->decimal_point;
    decimal_point_len = strlen (decimal_point);

    g_return_val_if_fail (decimal_point_len != 0, 0);

    decimal_point_pos = NULL;
    if (!strcmp (decimal_point, "."))
        return strtod (nptr, endptr);

    p = nptr;

    /* Skip leading space */
    while (isspace ((guchar)*p))
        p++;

    /* Skip leading optional sign */
    if (*p == '+' || *p == '-')
        p++;

    if (p[0] == '0' &&
        (p[1] == 'x' || p[1] == 'X')) {
        p += 2;
        /* HEX - find the (optional) decimal point */

        while (isxdigit ((guchar)*p))
            p++;

        if (*p == '.') {
            decimal_point_pos = p++;

            while (isxdigit ((guchar)*p))
                p++;

            if (*p == 'p' || *p == 'P')
                p++;
            if (*p == '+' || *p == '-')
                p++;
            while (isdigit ((guchar)*p))
                p++;
            end = p;
        } else if (strncmp (p, decimal_point, decimal_point_len) == 0) {
            return strtod (nptr, endptr);
        }
    } else {
        while (isdigit ((guchar)*p))
            p++;

        if (*p == '.') {
            decimal_point_pos = p++;

            while (isdigit ((guchar)*p))
                p++;

            if (*p == 'e' || *p == 'E')
                p++;
            if (*p == '+' || *p == '-')
                p++;
            while (isdigit ((guchar)*p))
                p++;
            end = p;
        } else if (strncmp (p, decimal_point, decimal_point_len) == 0) {
            return strtod (nptr, endptr);
        }
    }
    /* For the other cases, we need not convert the decimal point */

    if (!decimal_point_pos)
        return strtod (nptr, endptr);

    /* We need to convert the '.' to the locale specific decimal point */
    copy = g_malloc (end - nptr + 1 + decimal_point_len);

    c = copy;
    memcpy (c, nptr, decimal_point_pos - nptr);
    c += decimal_point_pos - nptr;
    memcpy (c, decimal_point, decimal_point_len);
    c += decimal_point_len;
    memcpy (c, decimal_point_pos + 1, end - (decimal_point_pos + 1));
    c += end - (decimal_point_pos + 1);
    *c = 0;

    val = strtod (copy, &fail_pos);

    if (fail_pos) {
        if (fail_pos > decimal_point_pos)
            fail_pos = (gchar *)nptr + (fail_pos - copy) - (decimal_point_len - 1);
        else
            fail_pos = (gchar *)nptr + (fail_pos - copy);
    }

    g_free (copy);

    if (endptr)
        *endptr = fail_pos;

    return val;
}

/**
 * e_ascii_dtostr:
 * @buffer: A buffer to place the resulting string in
 * @buf_len: The length of the buffer.
 * @format: The printf-style format to use for the
 *          code to use for converting.
 * @d: The double to convert
 *
 * Converts a double to a string, using the '.' as
 * decimal_point. To format the number you pass in
 * a printf-style formating string. Allowed conversion
 * specifiers are eEfFgG.
 *
 * If you want to generates enough precision that converting
 * the string back using @g_strtod gives the same machine-number
 * (on machines with IEEE compatible 64bit doubles) use the format
 * string "%.17g". If you do this it is guaranteed that the size
 * of the resulting string will never be larger than
 * @G_ASCII_DTOSTR_BUF_SIZE bytes.
 *
 * Return value: The pointer to the buffer with the converted string.
 **/
gchar *
e_ascii_dtostr (gchar *buffer, gint buf_len, const gchar *format, gdouble d)
{
    struct lconv *locale_data;
    const gchar *decimal_point;
    gint decimal_point_len;
    gchar *p;
    gint rest_len;
    gchar format_char;

    g_return_val_if_fail (buffer != NULL, NULL);
    g_return_val_if_fail (format[0] == '%', NULL);
    g_return_val_if_fail (strpbrk (format + 1, "'l%") == NULL, NULL);

    format_char = format[strlen (format) - 1];

    g_return_val_if_fail (format_char == 'e' || format_char == 'E' ||
                  format_char == 'f' || format_char == 'F' ||
                  format_char == 'g' || format_char == 'G',
                  NULL);

    if (format[0] != '%')
        return NULL;

    if (strpbrk (format + 1, "'l%"))
        return NULL;

    if (!(format_char == 'e' || format_char == 'E' ||
          format_char == 'f' || format_char == 'F' ||
          format_char == 'g' || format_char == 'G'))
        return NULL;


    g_snprintf (buffer, buf_len, format, d);

    locale_data = localeconv ();
    decimal_point = locale_data->decimal_point;
    decimal_point_len = strlen (decimal_point);

    g_return_val_if_fail (decimal_point_len != 0, NULL);

    if (strcmp (decimal_point, ".")) {
        p = buffer;

        if (*p == '+' || *p == '-')
            p++;

        while (isdigit ((guchar)*p))
            p++;

        if (strncmp (p, decimal_point, decimal_point_len) == 0) {
            *p = '.';
            p++;
            if (decimal_point_len > 1) {
                rest_len = strlen (p + (decimal_point_len-1));
                memmove (p, p + (decimal_point_len-1),
                     rest_len);
                p[rest_len] = 0;
            }
        }
    }

    return buffer;
}

gchar *
e_strdup_append_strings (gchar *first_string, ...)
{
    gchar *buffer;
    gchar *current;
    gint length;
    va_list args1;
    va_list args2;
    gchar *v_string;
    gint v_int;

    va_start (args1, first_string);
    G_VA_COPY (args2, args1);

    length = 0;

    v_string = first_string;
    while (v_string) {
        v_int = va_arg (args1, gint);
        if (v_int >= 0)
            length += v_int;
        else
            length += strlen (v_string);
        v_string = va_arg (args1, gchar *);
    }

    buffer  = g_new (gchar, length + 1);
    current = buffer;

    v_string = first_string;
    while (v_string) {
        v_int = va_arg (args2, gint);
        if (v_int < 0) {
            gint i;
            for (i = 0; v_string[i]; i++) {
                *(current++) = v_string[i];
            }
        } else {
            gint i;
            for (i = 0; v_string[i] && i < v_int; i++) {
                *(current++) = v_string[i];
            }
        }
        v_string = va_arg (args2, gchar *);
    }
    *(current++) = 0;

    va_end (args1);
    va_end (args2);

    return buffer;
}

cairo_font_options_t *
get_font_options (void)
{
    gchar *antialiasing, *hinting, *subpixel_order;
    GConfClient *gconf = gconf_client_get_default ();
    cairo_font_options_t *font_options = cairo_font_options_create ();

    /* Antialiasing */
    antialiasing = gconf_client_get_string (gconf,
            "/desktop/gnome/font_rendering/antialiasing", NULL);
    if (antialiasing == NULL)
        cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_DEFAULT);
    else {
        if (strcmp (antialiasing, "grayscale") == 0)
            cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_GRAY);
        else if (strcmp (antialiasing, "rgba") == 0)
            cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_SUBPIXEL);
        else if (strcmp (antialiasing, "none") == 0)
            cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_NONE);
        else
            cairo_font_options_set_antialias (font_options, CAIRO_ANTIALIAS_DEFAULT);
    }
    hinting = gconf_client_get_string (gconf,
            "/desktop/gnome/font_rendering/hinting", NULL);
    if (hinting == NULL)
        cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_DEFAULT);
    else {
        if (strcmp (hinting, "full") == 0)
            cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_FULL);
        else if (strcmp (hinting, "medium") == 0)
            cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_MEDIUM);
        else if (strcmp (hinting, "slight") == 0)
            cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_SLIGHT);
        else if (strcmp (hinting, "none") == 0)
            cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_NONE);
        else
            cairo_font_options_set_hint_style (font_options, CAIRO_HINT_STYLE_DEFAULT);
    }
    subpixel_order = gconf_client_get_string (gconf,
            "/desktop/gnome/font_rendering/rgba_order", NULL);
    if (subpixel_order == NULL)
        cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_DEFAULT);
    else {
        if (strcmp (subpixel_order, "rgb") == 0)
            cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_RGB);
        else if (strcmp (subpixel_order, "bgr") == 0)
            cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_BGR);
        else if (strcmp (subpixel_order, "vrgb") == 0)
            cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_VRGB);
        else if (strcmp (subpixel_order, "vbgr") == 0)
            cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_VBGR);
        else
            cairo_font_options_set_subpixel_order (font_options, CAIRO_SUBPIXEL_ORDER_DEFAULT);
    }
    g_free (antialiasing);
    g_free (hinting);
    g_free (subpixel_order);
    g_object_unref (gconf);
    return font_options;
}

/**
 * e_file_update_save_path:
 * @uri: URI to store
 * @free: If TRUE, free uri
 *
 * Save the save_dir path for evolution.  If free is TRUE, uri gets freed when
 * done.  Genearally, this should be called with the output of
 * gtk_file_chooser_get_current_folder_uri()  The URI must be a path URI, not a
 * file URI.
 **/
void
e_file_update_save_path (gchar *uri, gboolean free)
{
    GConfClient *gconf = gconf_client_get_default();
    GError *error = NULL;

    gconf_client_set_string(gconf, "/apps/evolution/mail/save_dir", uri, &error);
    if (error != NULL) {
        g_warning("%s (%s) %s", G_STRLOC, G_STRFUNC, error->message);
        g_clear_error(&error);
    }
    g_object_unref(gconf);
    if (free)
        g_free(uri);
}

/**
 * e_file_get_save_path:
 *
 * Return the save_dir path for evolution.  If there isn't a save_dir, returns
 * the users home directory.  Returns an allocated URI that should be freed by
 * the caller.
 **/
gchar *
e_file_get_save_path (void)
{
    GConfClient *gconf = gconf_client_get_default();
    GError *error = NULL;
    gchar *uri;

    uri = gconf_client_get_string(gconf, "/apps/evolution/mail/save_dir", &error);
    if (error != NULL) {
        g_warning("%s (%s) %s", G_STRLOC, G_STRFUNC, error->message);
        g_clear_error(&error);
    }
    g_object_unref(gconf);

    if (uri == NULL) {
        GFile *file;

        file = g_file_new_for_path (g_get_home_dir ());
        if (file) {
            uri = g_file_get_uri (file);
            g_object_unref (file);
        }
    }

    return (uri);
}

/* Evolution Locks for crash recovery */

#define LOCK_FILE ".running"

static const gchar *
get_lock_filename (void)
{
    static gchar *filename = NULL;

    if (G_UNLIKELY (filename == NULL))
        filename = g_build_filename (e_get_user_data_dir (), LOCK_FILE, NULL);

    return filename;
}

gboolean
e_file_lock_create ()
{
    const char *fname = get_lock_filename ();
    gboolean status = FALSE;

    int fd = g_creat (fname, S_IRUSR|S_IWUSR);
    if (fd == -1){
        g_warning ("Lock file '%s' creation failed, error %d\n", fname, errno);
    } else {
        status = TRUE;
        close (fd);
    }

    return status;
}

void
e_file_lock_destroy ()
{
    const char *fname = get_lock_filename ();

    if (g_unlink (fname) == -1){
        g_warning ("Lock destroy: failed to unlink file '%s'!",fname);
    }
}

gboolean 
e_file_lock_exists ()
{
    const char *fname = get_lock_filename ();

    return g_file_test (fname, G_FILE_TEST_EXISTS);
}

/**
 * e_util_guess_mime_type:
 * @filename: it's a local file name, or URI.
 * @localfile: set to TRUE if can check the local file content, FALSE to check only based on the filename itself.
 * Returns: NULL or newly allocated string with a mime_type of the given file. Free with g_free.
 *
 * Guesses mime_type for the given filename.
 **/
char *
e_util_guess_mime_type (const char *filename, gboolean localfile)
{
    char *mime_type = NULL;

    g_return_val_if_fail (filename != NULL, NULL);

    if (localfile) {
        GFile *file;

        if (strstr (filename, "://"))
            file = g_file_new_for_uri (filename);
        else
            file = g_file_new_for_path (filename);

        if (file) {
            GFileInfo *fi;

            fi = g_file_query_info (file, G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE, G_FILE_QUERY_INFO_NONE, NULL, NULL);
            if (fi) {
                mime_type = g_content_type_get_mime_type (g_file_info_get_content_type (fi));
    
                g_object_unref (fi);
            }

            g_object_unref (file);
        }
    }

    if (!mime_type) {
        /* file doesn't exists locally, thus guess based on the filename */
        gboolean uncertain = FALSE;
        gchar *content_type;

        content_type = g_content_type_guess (filename, NULL, 0, &uncertain);
        if (content_type) {
            mime_type = g_content_type_get_mime_type (content_type);
            g_free (content_type);
        }
    }

    return mime_type;
}

/**
 * e_util_filename_to_uri:
 * @filename: local file name.
 * Returns: either newly allocated string or NULL. Free with g_free.
 *
 * Converts local file name to URI.
 **/
char *
e_util_filename_to_uri (const char *filename)
{
    GFile *file;
    char *uri = NULL;

    g_return_val_if_fail (filename != NULL, NULL);

    file = g_file_new_for_path (filename);

    if (file) {
        uri = g_file_get_uri (file);
        g_object_unref (file);
    }

    return uri;
}

/**
 * e_util_uri_to_filename:
 * @uri: uri.
 * Returns: either newly allocated string or NULL. Free with g_free.
 *
 * Converts URI to local file name. NULL indicates no such local file name exists.
 **/
char *
e_util_uri_to_filename (const char *uri)
{
    GFile *file;
    char *filename = NULL;

    g_return_val_if_fail (uri != NULL, NULL);

    file = g_file_new_for_uri (uri);

    if (file) {
        filename = g_file_get_path (file);
        g_object_unref (file);
    }

    return filename;
}

/**
 * e_util_read_file:
 * @filename: File name to read.
 * @filename_is_uri: Whether the file name is URI, if not, then it's a local path.
 * @buffer: Read content or the file. Should not be NULL. Returned value should be freed with g_free.
 * @read: Number of actually read bytes. Should not be NULL.
 * @error: Here will be returned an error from reading operations. Can be NULL. Not every time is set when returned FALSE.
 * Returns: Whether was reading successful or not.
 *
 * Reads synchronously content of the file, to which is pointed either by path or by URI.
 * Mount point should be already mounted when calling this function.
 **/
gboolean
e_util_read_file (const char *filename, gboolean filename_is_uri, char **buffer, gsize *read, GError **error)
{
    GFile *file;
    GFileInfo *info;
    GError *err = NULL;
    gboolean res = FALSE;

    g_return_val_if_fail (filename != NULL, FALSE);
    g_return_val_if_fail (buffer != NULL, FALSE);
    g_return_val_if_fail (read != NULL, FALSE);

    *buffer = NULL;
    *read = 0;

    if (filename_is_uri)
        file = g_file_new_for_uri (filename);
    else
        file = g_file_new_for_path (filename);

    g_return_val_if_fail (file != NULL, FALSE);

    info = g_file_query_info (file, G_FILE_ATTRIBUTE_STANDARD_SIZE, G_FILE_QUERY_INFO_NONE, NULL, &err);

    if (!err && info) {
        guint64 sz;
        char *buff;

        sz = g_file_info_get_attribute_uint64 (info, G_FILE_ATTRIBUTE_STANDARD_SIZE);
        buff = g_malloc (sizeof (char) * sz);

        if (buff) {
            GInputStream *stream;

            stream = G_INPUT_STREAM (g_file_read (file, NULL, &err));

            if (!err && stream) {
                res = g_input_stream_read_all (stream, buff, sz, read, NULL, &err);

                if (err)
                    res = FALSE;
                
                if (res)
                    *buffer = buff;
                else
                    g_free (buff);
            }

            if (stream)
                g_object_unref (stream);
        }
    }

    if (info)
        g_object_unref (info);

    g_object_unref (file);

    if (err) {
        if (error)
            *error = err;
        else
            g_error_free (err);
    }

    return res;
}

GSList *
e_util_get_category_filter_options (void)
{
    GSList *res = NULL;
    GList *clist, *l;

    clist = e_categories_get_list ();
    for (l = clist; l; l = l->next) {
        const char *cname = l->data;
        struct _filter_option *fo = g_new0 (struct _filter_option, 1);

        fo->title = g_strdup (cname);
        fo->value = g_strdup (cname);
        res = g_slist_prepend (res, fo);
    }

    g_list_free (clist);

    return g_slist_reverse (res);
}