mds-kbdc: misc

Signed-off-by: Mattias Andrée <maandree@operamail.com>

4 files changed, 454 insertions, 342 deletions

diff --git a/src/mds-kbdc/builtin-functions.c b/src/mds-kbdc/builtin-functions.c
new file mode 100644
index 0000000..cfac8ac
--- /dev/null
+++ b/src/mds-kbdc/builtin-functions.c
@@ -0,0 +1,336 @@
+/**
+ * mds — A micro-display server
+ * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "builtin-functions.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+
+
+/**
+ * Define useful data for built-in function with 2 parameters
+ */
+#define define_2						\
+  const char32_t* restrict a = *args++;				\
+  const char32_t* restrict b = *args++;				\
+  size_t an = string_length(a);					\
+  size_t bn = string_length(b);					\
+  size_t i, n = an > bn ? an : bn;				\
+  char32_t* restrict rc = malloc((n + 1) * sizeof(char32_t));	\
+  if (rc == NULL)						\
+    return NULL;						\
+  rc[n] = -1
+
+/**
+ * Define useful data for built-in function with 1 parameter
+ */
+#define define_1						\
+  const char32_t* restrict a = *args++;				\
+  size_t i, n = string_length(a);				\
+  char32_t* restrict rc = malloc((n + 1) * sizeof(char32_t));	\
+  if (rc == NULL)						\
+    return NULL;						\
+  rc[n] = -1
+
+
+/**
+ * Definition of the built-in function add/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_add_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] + b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function sub/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_sub_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] - b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function mul/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_mul_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] * b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function div/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_div_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] / b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function mod/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_mod_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] % b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function rsh/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_rsh_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] << b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function lsh/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_lsh_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] >> b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function or/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_or_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] | b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function and/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_and_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] & b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function xor/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_xor_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] ^ b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function not/1
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_not_1(const char32_t** restrict args)
+{
+  define_1;
+  for (i = 0; i < n; i++)
+    rc[i] = !a[i];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function equals/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_equals_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] == b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function greater/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_greater_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] > b[i % bn];
+  return rc;
+}
+
+
+/**
+ * Definition of the built-in function less/2
+ * 
+ * @param   args  The arguments passed to the function
+ * @return        The return value of the function, `NULL` on error
+ */
+static char32_t* builtin_function_less_2(const char32_t** restrict args)
+{
+  define_2;
+  for (i = 0; i < n; i++)
+    rc[i] = a[i % an] < b[i % bn];
+  return rc;
+}
+
+
+/* static char32_t* builtin_function_set_3(const char32_t** restrict args);  (variable index value) */
+/* static char32_t* builtin_function_get_2(const char32_t** restrict args);  (variable index) */
+
+
+#undef define_1
+#undef define_2
+
+
+/**
+ * Check whether a function is a builtin function
+ * 
+ * @param   name       The name of the function
+ * @param   arg_count  The number of arguments to pass to the function
+ * @return             Whether the described function is a builtin function
+ */
+int builtin_function_defined(const char* restrict name, size_t arg_count)
+{
+  size_t i;
+  static const char* const BUILTIN_FUNCTIONS_2[] =
+    {
+      "add", "sub", "mul", "div", "mod", "rsh", "lsh", "or",
+      "and", "xor", "equals", "greater", "less", "get", NULL
+    };
+  
+  if (arg_count == 3)
+    return !strcmp(name, "set");
+  else if (arg_count == 1)
+    return !strcmp(name, "not");
+  else if (arg_count == 2)
+    for (i = 0; BUILTIN_FUNCTIONS_2[i]; i++)
+      if (!strcmp(name, BUILTIN_FUNCTIONS_2[i]))
+	return 1;
+  
+  return 0;
+}
+
+
+/**
+ * Invoke a builtin function
+ * 
+ * @param   name       The name of the function
+ * @param   arg_count  The number of arguments to pass to the function
+ * @param   args       The arguments to pass
+ * @return             The return value of the function, `NULL` on error
+ */
+char32_t* builtin_function_invoke(const char* restrict name, size_t arg_count, const char32_t** restrict args)
+{
+  if (arg_count == 3)
+    if (!strcmp(name, "set"))
+      return NULL; /* TODO builtin_function_set_3(args) */
+  
+  if (arg_count == 1)
+    if (!strcmp(name, "not"))
+      return builtin_function_not_1(args);
+  
+  if (arg_count != 2)
+    return NULL;
+  
+  if (!strcmp(name, "add"))      return builtin_function_add_2(args);
+  if (!strcmp(name, "sub"))      return builtin_function_sub_2(args);
+  if (!strcmp(name, "mul"))      return builtin_function_mul_2(args);
+  if (!strcmp(name, "div"))      return builtin_function_div_2(args);
+  if (!strcmp(name, "mod"))      return builtin_function_mod_2(args);
+  if (!strcmp(name, "rsh"))      return builtin_function_rsh_2(args);
+  if (!strcmp(name, "lsh"))      return builtin_function_lsh_2(args);
+  if (!strcmp(name, "or"))       return builtin_function_or_2(args);
+  if (!strcmp(name, "and"))      return builtin_function_and_2(args);
+  if (!strcmp(name, "xor"))      return builtin_function_xor_2(args);
+  if (!strcmp(name, "equals"))   return builtin_function_equals_2(args);
+  if (!strcmp(name, "greater"))  return builtin_function_greater_2(args);
+  if (!strcmp(name, "less"))     return builtin_function_less_2(args);
+  if (!strcmp(name, "get"))      return NULL; /* TODO builtin_function_get_2(args) */
+  
+  return NULL;
+}
+
diff --git a/src/mds-kbdc/functions.h b/src/mds-kbdc/builtin-functions.h
index 158c0b1..ebe3935 100644
--- a/src/mds-kbdc/functions.h
+++ b/src/mds-kbdc/builtin-functions.h
@@ -15,8 +15,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#ifndef MDS_MDS_KBDC_FUNCTIONS_H
-#define MDS_MDS_KBDC_FUNCTIONS_H
+#ifndef MDS_MDS_KBDC_BUILTIN_FUNCTIONS_H
+#define MDS_MDS_KBDC_BUILTIN_FUNCTIONS_H
 
 
 #include "string.h"
@@ -25,26 +25,26 @@
 #include <stdarg.h>
 
 
+
 /**
- * Check whether a function is defined.
+ * Check whether a function is a builtin function
  * 
- * @param   name       The name of the function.
- * @param   arg_count  The number of arguments to pass to the function.
- * @return             Whether the function is defined for the selected number of arguments.
+ * @param   name       The name of the function
+ * @param   arg_count  The number of arguments to pass to the function
+ * @return             Whether the described function is a builtin function
  */
-int function_check_defined(const char32_t* restrict name, size_t arg_count) __attribute__((nonnull));
+int builtin_function_defined(const char* restrict name, size_t arg_count) __attribute__((pure));
 
 /**
- * Invoke a function defined in the keyboard layout source code, or that is builtin.
+ * Invoke a builtin function
  * 
- * @param   name           The name of the function.
- * @param   arg_count      The number of arguments to pass to the function.
- * @param   ...:char32_t*  The arguments to pass, do not end with a sentinel.
- * @return                 The return value of the function, `NULL` on error.
+ * @param   name       The name of the function
+ * @param   arg_count  The number of arguments to pass to the function
+ * @param   args       The arguments to pass
+ * @return             The return value of the function, `NULL` on error
  */
-char32_t* function_invoke(const char32_t* restrict name, size_t arg_count, ...) __attribute__((nonnull));
+char32_t* builtin_function_invoke(const char* restrict name, size_t arg_count, const char32_t** restrict args);
 
-/* TODO define functions, check if function is built in */
 
 
 #endif
diff --git a/src/mds-kbdc/compile-layout.c b/src/mds-kbdc/compile-layout.c
index d6df226..e677c23 100644
--- a/src/mds-kbdc/compile-layout.c
+++ b/src/mds-kbdc/compile-layout.c
@@ -19,6 +19,7 @@
 /* TODO add call stack */
 
 #include "include-stack.h"
+#include "builtin-functions.h"
 #include "string.h"
 
 #include <stdlib.h>
@@ -150,8 +151,15 @@ static int pop_stack(void)
   return 0; /* TODO */
 }
 
-static int get_macro_lax(const char* restrict macro_name,
-			 const mds_kbdc_tree_macro_t** restrict macro,
+static int set_macro(const mds_kbdc_tree_macro_t* restrict macro,
+		     mds_kbdc_include_stack_t* macro_include_stack)
+{
+  (void) macro;
+  (void) macro_include_stack;
+  return 0; /* TODO */
+}
+
+static int get_macro_lax(const char* restrict macro_name, const mds_kbdc_tree_macro_t** restrict macro,
 			 mds_kbdc_include_stack_t** restrict macro_include_stack)
 {
   (void) macro_name;
@@ -174,6 +182,7 @@ static int get_macro(const mds_kbdc_tree_macro_call_t* restrict macro_call,
 }
 
 
+
 /**
  * Compile an include-statement
  * 
@@ -604,26 +613,11 @@ static int check_function_calls(const mds_kbdc_tree_t* restrict tree)
       t (check_function_calls(tree->if_.otherwise));
       break;
       
-    case C(LET):
-      t (check_function_calls(tree->let.value));
-      break;
-      
-    case C(ARRAY):
-      t (check_function_calls(tree->array.elements));
-      break;
-      
-    case C(KEYS):
-      t (check_function_calls_in_keys(&(tree->keys)));
-      break;
-      
-    case C(STRING):
-      t (check_function_calls_in_string(&(tree->string)));
-      break;
-      
-    case C(MAP):
-      t (check_function_calls(tree->map.sequence));
-      break;
-      
+    case C(LET):     t (check_function_calls(tree->let.value));            break;
+    case C(ARRAY):   t (check_function_calls(tree->array.elements));       break;
+    case C(KEYS):    t (check_function_calls_in_keys(&(tree->keys)));      break;
+    case C(STRING):  t (check_function_calls_in_string(&(tree->string)));  break;
+    case C(MAP):     t (check_function_calls(tree->map.sequence));         break;
     default:
       break;
     }
@@ -691,11 +685,37 @@ static int check_name_suffix(struct mds_kbdc_tree_callable* restrict tree)
 static int compile_function(mds_kbdc_tree_function_t* restrict tree)
 {
 #define t(expr)  fail_if ((r = (expr), r < 0));  if (r)  tree->processed = PROCESS_LEVEL
-  int r;
+  const mds_kbdc_tree_function_t* function;
+  mds_kbdc_include_stack_t* function_include_stack;
+  mds_kbdc_include_stack_t* our_include_stack = NULL;
+  char* suffixless;
+  char* suffix_start;
+  size_t arg_count;
+  int r, saved_errno;
   
   t (check_name_suffix((struct mds_kbdc_tree_callable*)tree));
   
-  /* TODO check for redefinition */
+  suffixless = strdup(tree->name);
+  fail_if (suffixless == NULL);
+  suffix_start = strchr(suffixless, '/');
+  *suffix_start++ = '\0';
+  arg_count = (size_t)atoll(suffix_start);
+  
+  if (builtin_function_defined(suffixless, arg_count))
+    {
+      NEW_ERROR(tree, ERROR, "function ‘%s’ is already defined as a builtin function", tree->name);
+      return 0;
+    }
+  /* TODO check for redefinition */ function = NULL, function_include_stack = NULL;
+  if (function)
+    {
+      NEW_ERROR(tree, ERROR, "function ‘%s’ is already defined", tree->name);
+      fail_if (mds_kbdc_include_stack_restore(function_include_stack));
+      NEW_ERROR(function, NOTE, "previously defined here");
+      fail_if (mds_kbdc_include_stack_restore(our_include_stack));
+      mds_kbdc_include_stack_free(our_include_stack);
+      return 0;
+    }
   
   t (check_marco_calls(tree->inner));
   t (check_function_calls(tree->inner));
@@ -703,8 +723,9 @@ static int compile_function(mds_kbdc_tree_function_t* restrict tree)
   /* TODO add definition */
   
   return 0;
- pfail:
-  return -1;
+  FAIL_BEGIN;
+  mds_kbdc_include_stack_free(our_include_stack);
+  FAIL_END;
 #undef t
 }
 
@@ -723,13 +744,14 @@ static int compile_macro(mds_kbdc_tree_macro_t* restrict tree)
   mds_kbdc_include_stack_t* our_include_stack = NULL;
   int r, saved_errno;
   
+  fail_if ((our_include_stack = mds_kbdc_include_stack_save(), our_include_stack == NULL));
+  
   t (check_name_suffix((struct mds_kbdc_tree_callable*)tree));
   
   t (get_macro_lax(tree->name, &macro, &macro_include_stack));
   if (macro)
     {
       NEW_ERROR(tree, ERROR, "macro ‘%s’ is already defined", tree->name);
-      fail_if ((our_include_stack = mds_kbdc_include_stack_save(), our_include_stack == NULL));
       fail_if (mds_kbdc_include_stack_restore(macro_include_stack));
       NEW_ERROR(macro, NOTE, "previously defined here");
       fail_if (mds_kbdc_include_stack_restore(our_include_stack));
@@ -740,7 +762,7 @@ static int compile_macro(mds_kbdc_tree_macro_t* restrict tree)
   t (check_marco_calls(tree->inner));
   t (check_function_calls(tree->inner));
   
-  /* TODO add definition */
+  t (set_macro(tree, our_include_stack));
   
   return 0;
   FAIL_BEGIN;
@@ -967,6 +989,38 @@ static int compile_array(mds_kbdc_tree_array_t* restrict tree)
 
 
 /**
+ * Check that a chain of strings and key-combinations
+ * does not contain NULL characters
+ * 
+ * @param   tree  The tree to check
+ * @return        Zero on success, -1 on error, 1 if any of
+ *                the elements contain a NULL character
+ */
+static int check_nonnul(mds_kbdc_tree_t* restrict tree)
+{
+  const char* restrict string;
+  int rc = 0;
+ again:
+  if (tree == NULL)
+    return rc;
+  
+  for (string = tree->string.string; *string; string++)
+    if ((string[0] == (char)0xC0) && (string[1] == (char)0x80))
+      {
+	NEW_ERROR(tree, ERROR, "NULL characters are not allowed in mappings");
+	tree->processed = PROCESS_LEVEL;
+	rc = 1;
+	break;
+      }
+  
+  tree = tree->next;
+  goto again;
+ pfail:
+   return -1;
+}
+
+
+/**
  * Compile a mapping- or value-statement
  * 
  * @param   tree  The tree to compile
@@ -980,17 +1034,32 @@ static int compile_map(mds_kbdc_tree_map_t* restrict tree)
   int saved_errno;
   
   fail_if ((seq = mds_kbdc_tree_dup(tree->sequence), seq = NULL));
-  fail_if ((res = mds_kbdc_tree_dup(tree->result),   res = NULL));
-  
   fail_if ((bad |= evaluate_element(seq), bad < 0));
-  fail_if ((bad |= evaluate_element(res), bad < 0));
-  if (bad)
-    return 0;
   
-  /* TODO */
+  if (tree->result)
+    {
+      fail_if ((res = mds_kbdc_tree_dup(tree->result), res = NULL));
+      fail_if ((bad |= evaluate_element(res), bad < 0));
+    }
   
-  /* NUL-characters (0xC0 0x80) is only allowed in value-statements */
+  if (bad)
+    goto done;
   
+  if (tree->result)
+    {
+      fail_if ((bad |= check_nonnul(seq), bad < 0));
+      fail_if ((bad |= check_nonnul(res), bad < 0));
+      if (bad)
+	goto done;
+      
+      /* TODO */
+    }
+  else
+    {
+      /* TODO */
+    }
+  
+ done:
   mds_kbdc_tree_free(seq);
   mds_kbdc_tree_free(res);
   return 0;
diff --git a/src/mds-kbdc/functions.c b/src/mds-kbdc/functions.c
deleted file mode 100644
index 33fa70d..0000000
--- a/src/mds-kbdc/functions.c
+++ /dev/null
@@ -1,293 +0,0 @@
-/**
- * mds — A micro-display server
- * Copyright © 2014  Mattias Andrée (maandree@member.fsf.org)
- * 
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- * 
- * 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 General Public License for more details.
- * 
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#include "functions.h"
-
-#include <stdlib.h>
-
-
-
-/**
- * Define useful data for built-in function with 2 parameters.
- */
-#define define_2						\
-  const char32_t* restrict a = va_arg(args, const char32_t*);	\
-  const char32_t* restrict b = va_arg(args, const char32_t*);	\
-  size_t an = string_length(a);					\
-  size_t bn = string_length(b);					\
-  size_t i, n = an > bn ? an : bn;				\
-  char32_t* restrict rc = malloc((n + 1) * sizeof(char32_t));	\
-  if (rc == NULL)						\
-    return NULL;						\
-  rc[n] = -1
-
-/**
- * Define useful data for built-in function with 1 parameter.
- */
-#define define_1						\
-  const char32_t* restrict a = va_arg(args, const char32_t*);	\
-  size_t i, n = string_length(a);				\
-  char32_t* restrict rc = malloc((n + 1) * sizeof(char32_t));	\
-  if (rc == NULL)						\
-    return NULL;						\
-  rc[n] = -1
-
-
-/**
- * Definition of the built-in function add/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_add_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] + b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function sub/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_sub_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] - b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function mul/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_mul_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] * b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function div/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_div_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] / b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function mod/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_mod_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] % b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function rsh/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_rsh_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] << b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function lsh/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_lsh_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] >> b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function or/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_or_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] | b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function and/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_and_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] & b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function xor/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_xor_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] ^ b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function not/1.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_not_1(va_list args)
-{
-  define_1;
-  for (i = 0; i < n; i++)
-    rc[i] = !a[i];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function equals/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_equals_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] == b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function greater/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_greater_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] > b[i % bn];
-  return rc;
-}
-
-
-/**
- * Definition of the built-in function less/2.
- * 
- * @param   args  The arguments passed to the function.
- * @return        The return value of the function, `NULL` on error.
- */
-static char32_t* function_builtin_less_2(va_list args)
-{
-  define_2;
-  for (i = 0; i < n; i++)
-    rc[i] = a[i % an] < b[i % bn];
-  return rc;
-}
-
-
-/* static char32_t* function_builtin_set_3(va_list args);  (variable index value) */
-/* static char32_t* function_builtin_get_2(va_list args);  (variable index) */
-
-
-#undef define_1
-#undef define_2
-
-
-/**
- * Check whether a function is defined.
- * 
- * @param   name       The name of the function.
- * @param   arg_count  The number of arguments to pass to the function.
- * @return             Whether the function is defined for the selected number of arguments.
- */
-int function_check_defined(const char32_t* restrict name, size_t arg_count)
-{
-  return 0; /* TODO */
-}
-
-
-/**
- * Invoke a function defined in the keyboard layout source code, or that is builtin.
- * 
- * @param   name           The name of the function.
- * @param   arg_count      The number of arguments to pass to the function.
- * @param   ...:char32_t*  The arguments to pass, do not end with a sentinel.
- * @return                 The return value of the function, `NULL` on error.
- */
-char32_t* function_invoke(const char32_t* restrict name, size_t arg_count, ...)
-{
-  return NULL; /* TODO */
-}
-