New function that parses a string as a double either in the C locale or

2001-10-06  Christopher James Lahey  <clahey@ximian.com>

	* gal/util/e-util.c, gal/util/e-util.h (e_flexible_strtod): New
	function that parses a string as a double either in the C locale
	or the current locale.
	(e_ascii_dtostr): New function that saves a double as a string as
	it would be saved in the C locale.

	* gal/util/e-xml-utils.c
	(e_xml_get_double_prop_by_name_with_default): Use
	e_flexible_strtod here.
	(e_xml_set_double_prop_by_name): Use e_ascii_dtostr here.

svn path=/trunk/; revision=13479

3 files changed, 368 insertions, 130 deletions

diff --git a/e-util/e-util.c b/e-util/e-util.c
index d3479a6661..345fd39bf4 100644
--- a/e-util/e-util.c
+++ b/e-util/e-util.c
@@ -1178,3 +1178,227 @@ size_t e_strftime_fix_am_pm(char *s, size_t max, const char *fmt, const struct t
 	return(ret);
 }
 
+/**
+ * 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 char *decimal_point;
+	int decimal_point_len;
+	const char *p, *decimal_point_pos;
+	const char *end = NULL; /* Silence gcc */
+	char *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_assert (decimal_point_len != 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 = (char *)nptr + (fail_pos - copy) - (decimal_point_len - 1);
+		else
+			fail_pos = (char *)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 char *decimal_point;
+	int decimal_point_len;
+	gchar *p;
+	int 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_assert (decimal_point_len != 0);
+
+	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;
+}
diff --git a/e-util/e-util.h b/e-util/e-util.h
index 179a2c2788..e9eb07ffa8 100644
--- a/e-util/e-util.h
+++ b/e-util/e-util.h
@@ -68,155 +68,169 @@ typedef enum {
 	E_FOCUS_START,
 	E_FOCUS_END
 } EFocus;
-int       g_str_compare                                                    (const void       *x,
-									    const void       *y);
-int       g_int_compare                                                    (const void       *x,
-									    const void       *y);
-char     *e_strdup_strip                                                   (const char       *string);
-
-void      e_free_object_list                                               (GList            *list);
-void      e_free_object_slist                                              (GSList           *list);
-void      e_free_string_list                                               (GList            *list);
-void      e_free_string_slist                                              (GSList           *list);
-
-char     *e_read_file                                                      (const char       *filename);
-int       e_write_file                                                     (const char       *filename,
-									    const char       *data,
-									    int               flags);
-int       e_mkdir_hier                                                     (const char       *path,
-									    mode_t            mode);
+int       g_str_compare                                                    (const void        *x,
+									    const void        *y);
+int       g_int_compare                                                    (const void        *x,
+									    const void        *y);
+char     *e_strdup_strip                                                   (const char        *string);
+void      e_free_object_list                                               (GList             *list);
+void      e_free_object_slist                                              (GSList            *list);
+void      e_free_string_list                                               (GList             *list);
+void      e_free_string_slist                                              (GSList            *list);
+char     *e_read_file                                                      (const char        *filename);
+int       e_write_file                                                     (const char        *filename,
+									    const char        *data,
+									    int                flags);
+int       e_mkdir_hier                                                     (const char        *path,
+									    mode_t             mode);
 
 gchar   **e_strsplit                                                	   (const gchar      *string,
 								    	    const gchar      *delimiter,
 								    	    gint              max_tokens);
-gchar    *e_strstrcase                                                     (const gchar      *haystack,
-									    const gchar      *needle);
-void      e_filename_make_safe                                             (gchar            *string);
-gchar    *e_format_number                                                  (gint              number);
-gchar    *e_format_number_float                                            (gfloat            number);
-gboolean  e_create_directory                                               (gchar            *directory);
+gchar    *e_strstrcase                                                     (const gchar       *haystack,
+									    const gchar       *needle);
+void      e_filename_make_safe                                             (gchar             *string);
+gchar    *e_format_number                                                  (gint               number);
+gchar    *e_format_number_float                                            (gfloat             number);
+gboolean  e_create_directory                                               (gchar             *directory);
 
 
 typedef int (*ESortCompareFunc) (const void *first,
 				 const void *second,
 				 gpointer    closure);
-void      e_sort                                                           (void             *base,
-									    size_t            nmemb,
-									    size_t            size,
-									    ESortCompareFunc  compare,
-									    gpointer          closure);
-void      e_bsearch                                                        (const void       *key,
-									    const void       *base,
-									    size_t            nmemb,
-									    size_t            size,
-									    ESortCompareFunc  compare,
-									    gpointer          closure,
-									    size_t           *start,
-									    size_t           *end);
-size_t    e_strftime_fix_am_pm                                             (char             *s,
-									    size_t            max,
-									    const char       *fmt,
-									    const struct tm  *tm);
-void      e_marshal_INT__INT_INT_POINTER                                   (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__INT_POINTER_INT_POINTER                           (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_NONE__OBJECT_DOUBLE_DOUBLE_BOOL                        (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_DOUBLE__OBJECT_DOUBLE_DOUBLE_BOOL                      (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_BOOL__OBJECT_DOUBLE_DOUBLE_BOOL                        (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_sort                                                           (void              *base,
+									    size_t             nmemb,
+									    size_t             size,
+									    ESortCompareFunc   compare,
+									    gpointer           closure);
+void      e_bsearch                                                        (const void        *key,
+									    const void        *base,
+									    size_t             nmemb,
+									    size_t             size,
+									    ESortCompareFunc   compare,
+									    gpointer           closure,
+									    size_t            *start,
+									    size_t            *end);
+size_t    e_strftime_fix_am_pm                                             (char              *s,
+									    size_t             max,
+									    const char        *fmt,
+									    const struct tm   *tm);
+
+
+/* String to/from double conversion functions */
+gdouble   e_flexible_strtod                                                (const gchar       *nptr,
+									    gchar            **endptr);
+/* 29 bytes should enough for all possible values that
+ * g_ascii_dtostr can produce with the %.17g format.
+ * Then add 10 for good measure */
+#define E_ASCII_DTOSTR_BUF_SIZE (29 + 10)
+gchar    *e_ascii_dtostr                                                   (gchar             *buffer,
+									    gint               buf_len,
+									    const gchar       *format,
+									    gdouble            d);
+
+
+/* Marshallers */
+void      e_marshal_INT__INT_INT_POINTER                                   (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__INT_POINTER_INT_POINTER                           (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_NONE__OBJECT_DOUBLE_DOUBLE_BOOL                        (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_DOUBLE__OBJECT_DOUBLE_DOUBLE_BOOL                      (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_BOOL__OBJECT_DOUBLE_DOUBLE_BOOL                        (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_INT_POINTER_POINTER_UINT_UINT e_marshal_NONE__INT_INT_POINTER_POINTER_INT_INT
-void      e_marshal_NONE__INT_INT_POINTER_POINTER_INT_INT                  (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_INT_POINTER_POINTER_INT_INT                  (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_POINTER_INT_POINTER_POINTER_UINT_UINT e_marshal_NONE__INT_POINTER_INT_POINTER_POINTER_INT_INT
-void      e_marshal_NONE__INT_POINTER_INT_POINTER_POINTER_INT_INT          (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_POINTER_INT_POINTER_POINTER_INT_INT          (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_INT_POINTER_UINT e_marshal_NONE__INT_INT_POINTER_INT
-void      e_marshal_NONE__INT_INT_POINTER_INT                              (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_INT_POINTER_INT                              (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_POINTER_INT_POINTER_UINT e_marshal_NONE__INT_POINTER_INT_POINTER_INT
-void      e_marshal_NONE__INT_POINTER_INT_POINTER_INT                      (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_POINTER_INT_POINTER_INT                      (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_BOOL__INT_INT_POINTER_INT_INT_UINT e_marshal_BOOL__INT_INT_POINTER_INT_INT_INT
-void      e_marshal_BOOL__INT_INT_POINTER_INT_INT_INT                      (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_BOOL__INT_INT_POINTER_INT_INT_INT                      (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_BOOL__INT_POINTER_INT_POINTER_INT_INT_UINT e_marshal_BOOL__INT_POINTER_INT_POINTER_INT_INT_INT
-void      e_marshal_BOOL__INT_POINTER_INT_POINTER_INT_INT_INT              (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_BOOL__INT_POINTER_INT_POINTER_INT_INT_INT              (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_INT_POINTER_INT_INT_POINTER_UINT_UINT e_marshal_NONE__INT_INT_POINTER_INT_INT_POINTER_INT_INT
-void      e_marshal_NONE__INT_INT_POINTER_INT_INT_POINTER_INT_INT          (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_INT_POINTER_INT_INT_POINTER_INT_INT          (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 #define e_marshal_NONE__INT_POINTER_INT_POINTER_INT_INT_POINTER_UINT_UINT e_marshal_NONE__INT_POINTER_INT_POINTER_INT_INT_POINTER_INT_INT
-void      e_marshal_NONE__INT_POINTER_INT_POINTER_INT_INT_POINTER_INT_INT  (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_NONE__POINTER_POINTER_INT                              (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_NONE__INT_POINTER_INT_POINTER                          (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__POINTER_POINTER                                   (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__POINTER_POINTER_POINTER                           (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__POINTER_POINTER_POINTER_POINTER                   (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__POINTER_POINTER_POINTER_POINTER_POINTER           (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_NONE__POINTER_INT_INT_INT                              (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
-void      e_marshal_INT__OBJECT_POINTER                                    (GtkObject        *object,
-									    GtkSignalFunc     func,
-									    gpointer          func_data,
-									    GtkArg           *args);
+void      e_marshal_NONE__INT_POINTER_INT_POINTER_INT_INT_POINTER_INT_INT  (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_NONE__POINTER_POINTER_INT                              (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_NONE__INT_POINTER_INT_POINTER                          (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__POINTER_POINTER                                   (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__POINTER_POINTER_POINTER                           (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__POINTER_POINTER_POINTER_POINTER                   (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__POINTER_POINTER_POINTER_POINTER_POINTER           (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_NONE__POINTER_INT_INT_INT                              (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
+void      e_marshal_INT__OBJECT_POINTER                                    (GtkObject         *object,
+									    GtkSignalFunc      func,
+									    gpointer           func_data,
+									    GtkArg            *args);
 
 
 #ifdef __cplusplus
diff --git a/e-util/e-xml-utils.c b/e-util/e-xml-utils.c
index 1285b5ce75..6ff68c5904 100644
--- a/e-util/e-xml-utils.c
+++ b/e-util/e-xml-utils.c
@@ -30,6 +30,7 @@
 #include <gnome-xml/parser.h>
 #include <gnome-xml/xmlmemory.h>
 #include "gal/util/e-i18n.h"
+#include "gal/util/e-util.h"
 
 xmlNode *
 e_xml_get_child_by_name (const xmlNode *parent, const xmlChar *child_name)
@@ -329,7 +330,7 @@ e_xml_get_double_prop_by_name_with_default (const xmlNode *parent, const xmlChar
 
 	prop = xmlGetProp ((xmlNode *) parent, prop_name);
 	if (prop != NULL) {
-		(void) sscanf (prop, "%lf", &ret_val);
+		ret_val = e_flexible_strtod (prop, NULL);
 		xmlFree (prop);
 	}
 	return ret_val;
@@ -338,18 +339,17 @@ e_xml_get_double_prop_by_name_with_default (const xmlNode *parent, const xmlChar
 void
 e_xml_set_double_prop_by_name(xmlNode *parent, const xmlChar *prop_name, gdouble value)
 {
-	gchar *valuestr;
+	char buffer[E_ASCII_DTOSTR_BUF_SIZE];
 
 	g_return_if_fail (parent != NULL);
 	g_return_if_fail (prop_name != NULL);
 
 	if (fabs (value) < 1e9 && fabs (value) > 1e-5) {
-		valuestr = g_strdup_printf ("%f", value);
+		e_ascii_dtostr (buffer, sizeof (buffer), "%.17f", value);
 	} else {
-		valuestr = g_strdup_printf ("%.*g", DBL_DIG, value);
+		e_ascii_dtostr (buffer, sizeof (buffer), "%.17g", value);
 	}
-	xmlSetProp (parent, prop_name, valuestr);
-	g_free (valuestr);
+	xmlSetProp (parent, prop_name, buffer);
 }
 
 gchar *