the ES command (send Scintilla message) now supports passing both wParam and lParam as null-terminated strings

* Being able to embed null bytes into the lParam string is
  practically useless - there aren't any messages where this is useful
  and where there are no native SciTECO counterparts - so this case is now catched
  and the null-byte separates wParam from lParam.
* wParam can be the empty string, but it is not supported to pass wParam as a
  string and lParam as the empty string.
  If the second string argument ends in ^@, lParam is popped from the stack instead.
* This is a temporary workaround until we can properly parse the Scintilla.iface and
  generate more elegant per-message wrappers.
* It in particular unlocks the SCI_SETREPRESENTATION and SCI_SETPROPERTY messages.
  The former allows us to write a special hex-editor macro which sets hexadecimal
  character representations, while the latter allows you to set lexer properties.
* The C-based lexers ("cpp" in Lexilla) can now take preprocessor definitions into account.
  This is disabled by default, unless you set lexer.c.defines before opening a file.
  You can also set it interactively and re-set the lexer. For instance:
  ^U[lexer.c.defines]NDEBUG$ M[lexer.set.c]

6 files changed, 44 insertions, 18 deletions

diff --git a/lib/lexers/c.tes b/lib/lexers/c.tes
index c0acea2..0f2b68d 100644
--- a/lib/lexers/c.tes
+++ b/lib/lexers/c.tes
diff --git a/lib/lexers/cpp.tes b/lib/lexers/cpp.tes
index 0f6a01a..7ac177f 100644
--- a/lib/lexers/cpp.tes
+++ b/lib/lexers/cpp.tes
diff --git a/lib/lexers/devicetree.tes b/lib/lexers/devicetree.tes
index 7551458..da6d876 100644
--- a/lib/lexers/devicetree.tes
+++ b/lib/lexers/devicetree.tes
diff --git a/lib/lexers/sciteco.tes b/lib/lexers/sciteco.tes
index ec023d7..7ca9c70 100644
--- a/lib/lexers/sciteco.tes
+++ b/lib/lexers/sciteco.tes
diff --git a/src/lexer.c b/src/lexer.c
index 1124b99..84ddcc3 100644
--- a/src/lexer.c
+++ b/src/lexer.c
@@ -133,9 +133,9 @@ teco_lexer_step(teco_view_t *view, teco_machine_main_t *machine,
 		 * The curly braces will be styled like regular commands.
 		 *
 		 * FIXME: This will not work with nested macro definitions.
-		 * FIXME: This cannot currently be disabled since SCI_SETPROPERTY
-		 * cannot be accessed with ES.
-		 * We could only map it to an ED flag.
+		 * FIXME: This cannot currently be disabled, not even with SCI_SETPROPERTY.
+		 * We could only map it to an ED flag or
+		 * rewrite the lexer against the ILexer5 interface, which requires C++.
 		 */
 		if ((escape_char == '{' || machine->expectstring.machine.escape_char == '{') &&
 		    teco_view_ssm(view, SCI_GETPROPERTYINT, (uptr_t)"lexer.sciteco.macrodef", TRUE))
diff --git a/src/symbols.c b/src/symbols.c
index 32a33da..66edd90 100644
--- a/src/symbols.c
+++ b/src/symbols.c
@@ -243,11 +243,6 @@ teco_state_scintilla_symbols_done(teco_machine_main_t *ctx, const teco_string_t
 			return NULL;
 		ctx->scintilla.iMessage = value;
 	}
-	if (!ctx->scintilla.wParam) {
-		if (!teco_expressions_pop_num_calc(&value, 0, error))
-			return NULL;
-		ctx->scintilla.wParam = value;
-	}
 
 	return &teco_state_scintilla_lparam;
 }
@@ -259,8 +254,11 @@ gboolean teco_state_scintilla_symbols_insert_completion(teco_machine_main_t *ctx
                                                         GError **error);
 
 /*$ ES scintilla message
- * -- Send Scintilla message
- * [lParam,][wParam,][message]ES[message][,wParam]$[lParam]$ -> result
+ * [lParam,][wParam,][message]ES$ -> result -- Send Scintilla message
+ * [lParam,][wParam]ES[message]$$ -> result
+ * [lParam]ES[message][,wParam]$$ -> result
+ * [wParam]ES[message]$[lParam]$ -> result
+ * [lParam]ES[message]$[wParam]^@[lParam]$ -> result
  *
  * Send Scintilla message with code specified by
  * <message>, <wParam> and <lParam>.
@@ -273,9 +271,15 @@ gboolean teco_state_scintilla_symbols_insert_completion(teco_machine_main_t *ctx
  * It is automatically null-terminated.
  * If the second string argument is empty, <lParam> is popped
  * from the stack instead.
+ * If the second string argument contains a null-byte (\fB^@\fP),
+ * both <wParam> and <lParam> are passed as null-terminated
+ * string pointers to Scintilla.
+ * If the second string ends in a null-byte, <lParam> is still
+ * popped from the stack.
  * Parameters popped from the stack may be omitted, in which
  * case 0 is implied.
- * The message's return value is pushed onto the stack.
+ * The message's return value is always pushed onto the stack
+ * (0 if the message has no documented return values).
  *
  * All messages defined by Scintilla (as C macros in Scintilla.h)
  * can be used by passing their name as a string to ES
@@ -283,7 +287,8 @@ gboolean teco_state_scintilla_symbols_insert_completion(teco_machine_main_t *ctx
  * The \(lqSCI_\(rq prefix may be omitted and message symbols
  * are case-insensitive.
  * Only the Lexilla style names (SCE_...)
- * may be used symbolically with the ES command as <wParam>.
+ * may be used symbolically with the ES command as <wParam> in
+ * the first string argument.
  * In interactive mode, symbols may be auto-completed by
  * pressing Tab.
  * String-building characters are by default interpreted
@@ -299,7 +304,7 @@ gboolean teco_state_scintilla_symbols_insert_completion(teco_machine_main_t *ctx
  * (shared library or DLL) is expected,
  * that implements the Lexilla protocol.
  * The \(lq.so\(rq or \(lq.dll\(rq extension is optional.
- * The concrete lexer name is the remaining of the string after
+ * The concrete lexer name is the remainder of the string after
  * the null-byte.
  * This allows you to use lexers from external lexer libraries
  * like Scintillua.
@@ -318,6 +323,8 @@ gboolean teco_state_scintilla_symbols_insert_completion(teco_machine_main_t *ctx
  * .BR Warning :
  * Almost all Scintilla messages may be dispatched using
  * this command.
+ * If called wrongly, you can easily crash the editor.
+ * Therefore it is not recommended to invoke ES interactively.
  * \*(ST does not keep track of the editor state changes
  * performed by these commands and cannot undo them.
  * You should never use it to change the editor state
@@ -458,12 +465,31 @@ teco_state_scintilla_lparam_done(teco_machine_main_t *ctx, const teco_string_t *
 			return NULL;
 	} else if (str->len > 0) {
 		/*
-		 * NOTE: There may even be messages that read strings
-		 * with embedded nulls.
+		 * Theoretically, Scintilla could use null bytes from the string specified.
+		 * This could only be the case for messages where the string length is
+		 * passed in wParam. In practice however, there are no such messages,
+		 * we would possible want to call.
+		 * Therefore we pass the first null-terminated string as wParam,
+		 * which unlocks useful messages like
+		 * SCI_SETREPRESENTATIONS and SCI_SETPROPERTY.
 		 */
-		lParam = (sptr_t)str->data;
-	} else {
-		teco_int_t v;
+		const gchar *p = memchr(str->data, '\0', str->len);
+		if (p) {
+			ctx->scintilla.wParam = (uptr_t)str->data;
+			if (str->len > p - str->data + 1)
+				lParam = (sptr_t)(p+1);
+		} else {
+			lParam = (sptr_t)str->data;
+		}
+	}
+
+	teco_int_t v;
+	if (!ctx->scintilla.wParam) {
+		if (!teco_expressions_pop_num_calc(&v, 0, error))
+			return NULL;
+		ctx->scintilla.wParam = v;
+	}
+	if (!lParam) {
 		if (!teco_expressions_pop_num_calc(&v, 0, error))
 			return NULL;
 		lParam = v;