libgimpcolor, app: gimp_color_parse_(css|hex|name)() renamed with _substring() suffix.

New functions with the same name as these functions are created, except without
the length argument (i.e. it's equivalent to calling these with -1).

The reason for this is that using strings with a length variant which may be
negative to switch to NUL-terminated strings are not bindable. At least in our
case, when testing in Python, the input string ended up as corrupted garbage and
GObject Introspection docs warns about such interfaces:

> In particular, avoid functions taking a const char * with a signed length that
> can be set to a negative value to let the function compute the string length
> in bytes. These functions are hard to bind, and require manual overrides.

(see: https://gi.readthedocs.io/en/latest/writingbindableapis.html#strings)

So instead, I create a simple version which runs on NUL-terminated strings only
and which is bound, whereas unbinding the generic length-version (making it
C-only, or maybe usable in some other bindings which ignore the (skip)
annotation; apparently some do this).

app/core/gimpgradient-load.c

@@ -504,7 +504,7 @@ svg_parse_gradient_stop_style_prop (SvgStop     *stop,
   if (strcmp (name, "stop-color") == 0)
     {
       g_clear_object (&stop->color);
-      stop->color = gimp_color_parse_css (value, -1);
+      stop->color = gimp_color_parse_css (value);
     }
   else if (strcmp (name, "stop-opacity") == 0)
     {

app/core/gimppalette-load.c

@@ -1313,7 +1313,7 @@ gimp_palette_load_css (GimpContext   *context,
               GeglColor *color;
               gchar     *word = g_match_info_fetch_named (matches, "param");
 
-              color = gimp_color_parse_css (word, -1);
+              color = gimp_color_parse_css (word);
               if (color)
                 {
                   if (! gimp_palette_find_entry (palette, color, NULL))

app/widgets/gimppanedbox.c

@@ -366,7 +366,7 @@ gimp_paned_box_drop_indicator_draw (GtkWidget *widget,
   gdouble       rgba[4];
   gsize         i;
 
-  color = gimp_color_parse_hex (DROP_HIGHLIGHT_COLOR, -1);
+  color = gimp_color_parse_hex (DROP_HIGHLIGHT_COLOR);
   gegl_color_get_pixel (color, babl_format ("R'G'B'A double"), rgba);
 
   for (i = 0; i < G_N_ELEMENTS (paned_box->p->dnd_highlights); i++)

libgimpcolor/gimpcolor-parse.c

@@ -207,13 +207,65 @@ static const ColorEntry named_colors[] =
 
 /**
  * gimp_color_parse_css:
+ * @css: (type utf8): a string describing a color in CSS notation
+ *
+ * Attempts to parse a string describing an sRGB color in CSS notation. This can
+ * be either a numerical representation (`rgb(255,0,0)` or `rgb(100%,0%,0%)`)
+ * or a hexadecimal notation as parsed by [func@color_parse_hex] (`##ff0000`) or
+ * a color name as parsed by [func@color_parse_css] (`red`).
+ *
+ * Additionally the `rgba()`, `hsl()` and `hsla()` functions are supported too.
+ *
+ * Returns: (transfer full): a newly allocated [class@Gegl.Color] if @css was
+ *                           parsed successfully, %NULL otherwise
+ **/
+GeglColor *
+gimp_color_parse_css (const gchar *css)
+{
+  return gimp_color_parse_css_substring (css, -1);
+}
+
+/**
+ * gimp_color_parse_hex:
+ * @hex: (type utf8): a string describing a color in hexadecimal notation
+ *
+ * Attempts to parse a string describing a sRGB color in hexadecimal
+ * notation (optionally prefixed with a '#').
+ *
+ * Returns: (transfer full): a newly allocated color representing @hex.
+ **/
+GeglColor *
+gimp_color_parse_hex (const gchar *hex)
+{
+  return gimp_color_parse_hex_substring (hex, -1);
+}
+
+/**
+ * gimp_color_parse_name:
+ * @name: (type utf8): a color name (in UTF-8 encoding)
+ *
+ * Attempts to parse a color name. This function accepts [SVG 1.1 color
+ * keywords](https://www.w3.org/TR/SVG11/types.html#ColorKeywords).
+ *
+ * Returns: (transfer full): a sRGB color as defined in "4.4. Recognized color
+ *          keyword names" list of SVG 1.1 specification, if @name was parsed
+ *          successfully, %NULL otherwise
+ **/
+GeglColor *
+gimp_color_parse_name (const gchar *name)
+{
+  return gimp_color_parse_name_substring (name, -1);
+}
+
+/**
+ * gimp_color_parse_css_substring: (skip)
  * @css: (array length=len): a string describing a color in CSS notation
  * @len: the length of @css, in bytes. or -1 if @css is nul-terminated
  *
  * Attempts to parse a string describing an sRGB color in CSS notation. This can
- * be either a numerical representation (`rgb(255,0,0)` or `rgb(100%,0%,0%)`)
+ * be either a numerical representation (`rgb(255,0,0)` or `rgb(100%,0%,0%)`) or
- * or a hexadecimal notation as parsed by gimp_color_parse_hex()
+ * a hexadecimal notation as parsed by [func@color_parse_hex] (`##ff0000`) or a
- * (`##ff0000`) or a color name as parsed by gimp_color_parse_name() (`red`).
+ * color name as parsed by [func@color_parse_name] (`red`).
  *
  * Additionally the `rgba()`, `hsl()` and `hsla()` functions are supported too.
  *
@@ -223,8 +275,8 @@ static const ColorEntry named_colors[] =
  * Since: 2.2
  **/
 GeglColor *
-gimp_color_parse_css (const gchar *css,
+gimp_color_parse_css_substring (const gchar *css,
-                      gint         len)
+                                gint         len)
 {
   gchar     *tmp;
   GeglColor *color;
@@ -244,7 +296,7 @@ gimp_color_parse_css (const gchar *css,
 }
 
 /**
- * gimp_color_parse_hex:
+ * gimp_color_parse_hex_substring: (skip)
  * @hex: (array length=len): a string describing a color in hexadecimal notation
  * @len: the length of @hex, in bytes. or -1 if @hex is nul-terminated
  *
@@ -258,8 +310,8 @@ gimp_color_parse_css (const gchar *css,
  * Since: 2.2
  **/
 GeglColor *
-gimp_color_parse_hex (const gchar *hex,
+gimp_color_parse_hex_substring (const gchar *hex,
-                      gint         len)
+                                gint         len)
 {
   GeglColor *result;
   gchar     *tmp;
@@ -276,7 +328,7 @@ gimp_color_parse_hex (const gchar *hex,
 }
 
 /**
- * gimp_color_parse_name:
+ * gimp_color_parse_name_substring: (skip)
  * @name: (array length=len): a color name (in UTF-8 encoding)
  * @len:  the length of @name, in bytes. or -1 if @name is nul-terminated
  *
@@ -290,8 +342,8 @@ gimp_color_parse_hex (const gchar *hex,
  * Since: 2.2
  **/
 GeglColor *
-gimp_color_parse_name (const gchar *name,
+gimp_color_parse_name_substring (const gchar *name,
-                       gint         len)
+                                 gint         len)
 {
   gchar     *tmp;
   GeglColor *result;

libgimpcolor/gimpcolor.def

@@ -33,8 +33,11 @@ EXPORTS
 	gimp_color_managed_simulation_intent_changed
 	gimp_color_managed_simulation_profile_changed
 	gimp_color_parse_css
+	gimp_color_parse_css_substring
 	gimp_color_parse_hex
+	gimp_color_parse_hex_substring
 	gimp_color_parse_name
+	gimp_color_parse_name_substring
 	gimp_color_profile_get_copyright
 	gimp_color_profile_get_description
 	gimp_color_profile_get_format

libgimpcolor/gimpcolor.h

@@ -53,11 +53,15 @@ void        gimp_color_set_alpha                 (GeglColor   *color,
 gboolean    gimp_color_is_perceptually_identical (GeglColor   *color1,
                                                   GeglColor   *color2);
 
-GeglColor * gimp_color_parse_css                 (const gchar *css,
+GeglColor * gimp_color_parse_css                 (const gchar *css);
+GeglColor * gimp_color_parse_hex                 (const gchar *hex);
+GeglColor * gimp_color_parse_name                (const gchar *name);
+
+GeglColor * gimp_color_parse_css_substring       (const gchar *css,
                                                   gint         len);
-GeglColor * gimp_color_parse_hex                 (const gchar *hex,
+GeglColor * gimp_color_parse_hex_substring       (const gchar *hex,
                                                   gint         len);
-GeglColor * gimp_color_parse_name                (const gchar *name,
+GeglColor * gimp_color_parse_name_substring      (const gchar *name,
                                                   gint         len);
 
 gboolean    gimp_color_is_out_of_self_gamut      (GeglColor   *color);

libgimpwidgets/gimpcolorhexentry.c

@@ -320,8 +320,8 @@ gimp_color_hex_entry_events (GtkWidget *widget,
             gsize      len   = strlen (text);
 
             if (len > 0 &&
-                ((color = gimp_color_parse_hex (text, len)) ||
+                ((color = gimp_color_parse_hex_substring (text, len)) ||
-                 (color = gimp_color_parse_name (text, -1))))
+                 (color = gimp_color_parse_name (text))))
               {
                 gimp_color_hex_entry_set_color (entry, color);
                 g_object_unref (color);
@@ -355,7 +355,7 @@ gimp_color_hex_entry_matched (GtkEntryCompletion *completion,
                       COLUMN_NAME, &name,
                       -1);
 
-  if ((color = gimp_color_parse_name (name, -1)))
+  if ((color = gimp_color_parse_name (name)))
     gimp_color_hex_entry_set_color (entry, color);
 
   g_free (name);

plug-ins/script-fu/libscriptfu/script-fu-color.c

@@ -109,7 +109,7 @@ sf_color_arg_set_default_by_name (SFArg *arg,
 
   /* Create a default value for the old-style interface.
    */
-  if (! (color = gimp_color_parse_css (name_of_default, -1)))
+  if (! (color = gimp_color_parse_css (name_of_default)))
     {
       result = FALSE;
     }
@@ -178,5 +178,5 @@ sf_color_get_repr_from_gegl_color (GeglColor *color)
 GeglColor *
 sf_color_get_color_from_name (gchar *color_name)
 {
-  return gimp_color_parse_css (color_name, -1);
+  return gimp_color_parse_css (color_name);
 }