evolution/libevolution-utils/evolution-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:
 *		Srinivasa Ragavan <sragavan@gnome.org>
 *
 * Copyright (C) 2012 Intel Corporation (www.intel.com)
 *
 */

#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 "evolution-util.h"

/**
 * 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.
 *
 * Returns: 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.
 *
 * Returns: 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;
}

/**
 * e_builder_get_widget:
 * @builder: a #GtkBuilder
 * @widget_name: name of a widget in @builder
 *
 * Gets the widget named @widget_name.  Note that this function does not
 * increment the reference count of the returned widget.  If @widget_name
 * could not be found in the @builder<!-- -->'s object tree, a run-time
 * warning is emitted since this usually indicates a programming error.
 *
 * This is a convenience function to work around the awkwardness of
 * #GtkBuilder returning #GObject pointers, when the vast majority of
 * the time you want a #GtkWidget pointer.
 *
 * If you need something from @builder other than a #GtkWidget, or you
 * want to test for the existence of some widget name without incurring
 * a run-time warning, use gtk_builder_get_object().
 *
 * Returns: the widget named @widget_name, or %NULL
 **/
GtkWidget *
e_builder_get_widget (GtkBuilder *builder,
                      const gchar *widget_name)
{
	GObject *object;

	g_return_val_if_fail (GTK_IS_BUILDER (builder), NULL);
	g_return_val_if_fail (widget_name != NULL, NULL);

	object = gtk_builder_get_object (builder, widget_name);
	if (object == NULL) {
		g_warning ("Could not find widget '%s'", widget_name);
		return NULL;
	}

	return GTK_WIDGET (object);
}

/**
 * e_load_ui_builder_definition:
 * @builder: a #GtkBuilder
 * @basename: basename of the UI definition file
 *
 * Loads a UI definition into @builder from Evolution's UI directory.
 * Failure here is fatal, since the application can't function without
 * its UI definitions.
 **/
void
e_load_ui_builder_definition (GtkBuilder *builder,
                              const gchar *basename)
{
	gchar *filename;
	GError *error = NULL;

	g_return_if_fail (GTK_IS_BUILDER (builder));
	g_return_if_fail (basename != NULL);

	filename = g_build_filename (EVOLUTION_UIDIR, basename, NULL);
	gtk_builder_add_from_file (builder, filename, &error);
	g_free (filename);

	if (error != NULL) {
		g_error ("%s: %s", basename, error->message);
		g_assert_not_reached ();
	}
}