Bug 684429 - Unable to edit text: error message states "problems..."

This fix is entirely sick, so is our method of serializing units,
which we write out as (unit foo bar) instead of (unit "foo bar"). The
assumption that caused this shit was that a unit's "identifier" is
really an identifier in the C-ish sense, when in fact it's just a
random user entered string.

Here, we try to parse at least the default units shipped with gimp,
and we add code to parse (unit "foo bar") in order to be compatible
with future correct unit serializing.

libgimpconfig/gimpconfig-deserialize.c

@@ -88,6 +88,9 @@ static GTokenType  gimp_config_deserialize_value_array (GValue     *value,
                                                         GimpConfig *config,
                                                         GParamSpec *prop_spec,
                                                         GScanner   *scanner);
+static GTokenType  gimp_config_deserialize_unit        (GValue     *value,
+                                                        GParamSpec *prop_spec,
+                                                        GScanner   *scanner);
 static GTokenType  gimp_config_deserialize_any         (GValue     *value,
                                                         GParamSpec *prop_spec,
                                                         GScanner   *scanner);
@@ -356,6 +359,10 @@ gimp_config_deserialize_value (GValue     *value,
       return gimp_config_deserialize_value_array (value,
                                                   config, prop_spec, scanner);
     }
+  else if (prop_spec->value_type == GIMP_TYPE_UNIT)
+    {
+      return gimp_config_deserialize_unit (value, prop_spec, scanner);
+    }
 
   /*  This fallback will only work for value_types that
    *  can be transformed from a string value.
@@ -742,12 +749,98 @@ gimp_config_deserialize_value_array (GValue     *value,
   return G_TOKEN_RIGHT_PAREN;
 }
 
+/* This function is entirely sick, so is our method of serializing
+ * units, which we write out as (unit foo bar) instead of
+ * (unit "foo bar"). The assumption that caused this shit was that a
+ * unit's "identifier" is really an identifier in the C-ish sense,
+ * when in fact it's just a random user entered string.
+ *
+ * Here, we try to parse at least the default units shipped with gimp,
+ * and we add code to parse (unit "foo bar") in order to be compatible
+ * with future correct unit serializing.
+ */
+static GTokenType
+gimp_config_deserialize_unit (GValue     *value,
+                              GParamSpec *prop_spec,
+                              GScanner   *scanner)
+{
+  gchar      *old_cset_skip_characters;
+  gchar      *old_cset_identifier_first;
+  gchar      *old_cset_identifier_nth;
+  GString    *buffer;
+  GValue      src = G_VALUE_INIT;
+  GTokenType  token;
+
+  /* parse the next token *before* reconfiguring the scanner, so it
+   * skips whitespace first
+   */
+  token = g_scanner_peek_next_token (scanner);
+
+  if (token == G_TOKEN_STRING)
+    return gimp_config_deserialize_any (value, prop_spec, scanner);
+
+  old_cset_skip_characters  = scanner->config->cset_skip_characters;
+  old_cset_identifier_first = scanner->config->cset_identifier_first;
+  old_cset_identifier_nth   = scanner->config->cset_identifier_nth;
+
+  scanner->config->cset_skip_characters  = "";
+  scanner->config->cset_identifier_first = ( G_CSET_a_2_z G_CSET_A_2_Z "." );
+  scanner->config->cset_identifier_nth   = ( G_CSET_a_2_z G_CSET_A_2_Z
+                                             G_CSET_DIGITS "-_." );
+
+  buffer = g_string_new ("");
+
+  while (g_scanner_peek_next_token (scanner) != G_TOKEN_RIGHT_PAREN)
+    {
+      token = g_scanner_peek_next_token (scanner);
+
+      if (token == G_TOKEN_IDENTIFIER)
+        {
+          g_scanner_get_next_token (scanner);
+          g_string_append (buffer, scanner->value.v_identifier);
+        }
+      else if (token == G_TOKEN_CHAR)
+        {
+          g_scanner_get_next_token (scanner);
+          g_string_append_c (buffer, scanner->value.v_char);
+        }
+      else if (token == ' ')
+        {
+          g_scanner_get_next_token (scanner);
+          g_string_append_c (buffer, token);
+        }
+      else
+        {
+          token = G_TOKEN_IDENTIFIER;
+          goto cleanup;
+        }
+    }
+
+  g_value_init (&src, G_TYPE_STRING);
+  g_value_set_static_string (&src, buffer->str);
+  g_value_transform (&src, value);
+  g_value_unset (&src);
+
+  token = G_TOKEN_RIGHT_PAREN;
+
+ cleanup:
+
+  g_string_free (buffer, TRUE);
+
+  scanner->config->cset_skip_characters  = old_cset_skip_characters;
+  scanner->config->cset_identifier_first = old_cset_identifier_first;
+  scanner->config->cset_identifier_nth   = old_cset_identifier_nth;
+
+  return token;
+}
+
 static GTokenType
 gimp_config_deserialize_any (GValue     *value,
                              GParamSpec *prop_spec,
                              GScanner   *scanner)
 {
-  GValue src = { 0, };
+  GValue     src = G_VALUE_INIT;
+  GTokenType token;
 
   if (!g_value_type_transformable (G_TYPE_STRING, prop_spec->value_type))
     {
@@ -756,13 +849,23 @@ gimp_config_deserialize_any (GValue     *value,
       return G_TOKEN_NONE;
     }
 
-  if (g_scanner_peek_next_token (scanner) != G_TOKEN_IDENTIFIER)
+  token = g_scanner_peek_next_token (scanner);
+
+  if (token != G_TOKEN_IDENTIFIER &&
+      token != G_TOKEN_STRING)
+    {
       return G_TOKEN_IDENTIFIER;
+    }
 
   g_scanner_get_next_token (scanner);
 
   g_value_init (&src, G_TYPE_STRING);
+
+  if (token == G_TOKEN_IDENTIFIER)
     g_value_set_static_string (&src, scanner->value.v_identifier);
+  else
+    g_value_set_static_string (&src, scanner->value.v_string);
+
   g_value_transform (&src, value);
   g_value_unset (&src);