vis: add infrastructure for user specified operators

4 files changed, 35 insertions, 5 deletions

diff --git a/vis-core.h b/vis-core.h
index f182e2a..9cc26f3 100644
--- a/vis-core.h
+++ b/vis-core.h
@@ -37,7 +37,7 @@ struct Mode {
 	bool visual;                        /* whether text selection is possible in this mode */
 };
 
-typedef struct {
+struct OperatorContext {
 	int count;        /* how many times should the command be executed? */
 	Register *reg;    /* always non-NULL, set to a default register */
 	Filerange range;  /* which part of the file should be affected by the operator */
@@ -45,12 +45,14 @@ typedef struct {
 	size_t newpos;    /* new position after motion or EPOS if none given */
 	bool linewise;    /* should the changes always affect whole lines? */
 	const Arg *arg;   /* arbitrary arguments */
-} OperatorContext;
+	void *context;    /* used by user-registered operators */
+};
 
 typedef struct {
 	/* operator logic, returns new cursor position, if EPOS is
 	 * the cursor is disposed (except if it is the primary one) */
-	size_t (*func)(Vis*, Text*, OperatorContext*);
+	VisOperatorFunction *func;
+	void *context;
 } Operator;
 
 typedef struct { /* Motion implementation, takes a cursor postion and returns a new one */
@@ -200,6 +202,7 @@ struct Vis {
 	Array actions_user;                  /* dynamically allocated editor actions */
 	lua_State *lua;                      /* lua context used for syntax highligthing */
 	VisEvent *event;
+	Array operators;
 	Array motions;
 	Array textobjects;
 	Array bindings;
diff --git a/vis-operators.c b/vis-operators.c
index 8038a2d..494774c 100644
--- a/vis-operators.c
+++ b/vis-operators.c
@@ -245,6 +245,18 @@ static size_t op_filter(Vis *vis, Text *txt, OperatorContext *c) {
 	return text_size(txt) + 1; /* do not change cursor position, would destroy selection */
 }
 
+int vis_operator_register(Vis *vis, VisOperatorFunction *func, void *context) {
+	Operator *op = calloc(1, sizeof *op);
+	if (!op)
+		return -1;
+	op->func = func;
+	op->context = context;
+	if (array_add_ptr(&vis->operators, op))
+		return VIS_OP_LAST + array_length(&vis->operators) - 1;
+	free(op);
+	return -1;
+}
+
 bool vis_operator(Vis *vis, enum VisOperator id, ...) {
 	va_list ap;
 	va_start(ap, id);
@@ -292,9 +304,16 @@ bool vis_operator(Vis *vis, enum VisOperator id, ...) {
 	default:
 		break;
 	}
-	if (id >= LENGTH(vis_operators))
+
+	const Operator *op = NULL;
+	if (id < LENGTH(vis_operators))
+		op = &vis_operators[id];
+	else
+		op = array_get_ptr(&vis->operators, id - VIS_OP_LAST);
+
+	if (!op)
 		goto err;
-	const Operator *op = &vis_operators[id];
+
 	if (vis->mode->visual) {
 		vis->action.op = op;
 		vis_do(vis);
diff --git a/vis.c b/vis.c
index 4c93872..06546ab 100644
--- a/vis.c
+++ b/vis.c
@@ -676,6 +676,7 @@ Vis *vis_new(Ui *ui, VisEvent *event) {
 	vis->change_colors = true;
 	vis->registers[VIS_REG_BLACKHOLE].type = REGISTER_BLACKHOLE;
 	vis->registers[VIS_REG_CLIPBOARD].type = REGISTER_CLIPBOARD;
+	array_init(&vis->operators);
 	array_init(&vis->motions);
 	array_init(&vis->textobjects);
 	array_init(&vis->bindings);
@@ -745,6 +746,7 @@ void vis_free(Vis *vis) {
 	buffer_release(&vis->input_queue);
 	for (int i = 0; i < VIS_MODE_INVALID; i++)
 		map_free(vis_modes[i].bindings);
+	array_release_full(&vis->operators);
 	array_release_full(&vis->motions);
 	array_release_full(&vis->textobjects);
 	while (array_length(&vis->bindings))
@@ -852,6 +854,7 @@ void vis_do(Vis *vis) {
 			.reg = reg,
 			.linewise = linewise,
 			.arg = &a->arg,
+			.context = a->op ? a->op->context : NULL,
 		};
 
 		bool err = false;
diff --git a/vis.h b/vis.h
index 913a503..6c6e0fe 100644
--- a/vis.h
+++ b/vis.h
@@ -224,6 +224,7 @@ enum VisOperator {
 	VIS_OP_PUT_AFTER_END,
 	VIS_OP_PUT_BEFORE,
 	VIS_OP_PUT_BEFORE_END,
+	VIS_OP_LAST, /* has to be last enum member */
 };
 
 /* set operator to execute, has immediate effect if
@@ -242,6 +243,10 @@ enum VisOperator {
  */
 bool vis_operator(Vis*, enum VisOperator, ...);
 
+typedef struct OperatorContext OperatorContext;
+typedef size_t (VisOperatorFunction)(Vis*, Text*, OperatorContext*);
+int vis_operator_register(Vis*, VisOperatorFunction*, void *context);
+
 enum VisMotion {
 	VIS_MOVE_LINE_DOWN,
 	VIS_MOVE_LINE_UP,