bshell: re-organise build into three separate components

bshell: the front-end binary
bshell.runtime: contains the parser, compiler, and classes needed to run bshell scripts
bshell.core: contains the builtin commandlets and aliases

bshell.runtime/compile/command.c

@@ -0,0 +1,74 @@
+#include "compile-node.h"
+
+enum bshell_status cmdcall_load(
+	struct compile_ctx *ctx,
+	struct compile_value *value)
+{
+	struct bshell_cmdcall_ast_node *cmdcall;
+	cmdcall = (struct bshell_cmdcall_ast_node *)value->v_node;
+	bshell_scriptblock_push_instruction(ctx->c_block, BSHELL_OPCODE_PEXEC, 1);
+	return BSHELL_SUCCESS;
+}
+
+enum bshell_status pipeline_load(
+	struct compile_ctx *ctx,
+	struct compile_value *value)
+{
+	struct bshell_pipeline_ast_node *pipeline;
+	pipeline = (struct bshell_pipeline_ast_node *)value->v_node;
+	size_t nr_items = fx_queue_length(&pipeline->n_stages);
+	bshell_scriptblock_push_instruction(
+		ctx->c_block,
+		BSHELL_OPCODE_PEXEC,
+		nr_items);
+	return BSHELL_SUCCESS;
+}
+
+static const struct compile_value_type cmdcall_type = {
+	.v_load = cmdcall_load,
+};
+
+static const struct compile_value_type pipeline_type = {
+	.v_load = pipeline_load,
+};
+
+struct compile_result compile_cmdcall(
+	struct compile_ctx *ctx,
+	struct bshell_ast_node *src)
+{
+	struct bshell_cmdcall_ast_node *cmdcall;
+	cmdcall = (struct bshell_cmdcall_ast_node *)src;
+	size_t nr_args = fx_queue_length(&cmdcall->n_args);
+	for (size_t i = 0; i < nr_args; i++) {
+		struct compile_value *arg = compile_pop_value(ctx);
+		compile_value_load(ctx, arg);
+		compile_value_destroy(arg);
+	}
+
+	bshell_scriptblock_push_instruction(
+		ctx->c_block,
+		BSHELL_OPCODE_LDCMD,
+		nr_args);
+
+	compile_push_value(ctx, &cmdcall_type, src);
+	return COMPILE_OK(0);
+}
+
+struct compile_result compile_pipeline(
+	struct compile_ctx *ctx,
+	struct bshell_ast_node *src)
+{
+	struct bshell_pipeline_ast_node *pipeline;
+	pipeline = (struct bshell_pipeline_ast_node *)src;
+	size_t nr_items = fx_queue_length(&pipeline->n_stages);
+	for (size_t i = 0; i < nr_items; i++) {
+		struct compile_value *item = compile_pop_value(ctx);
+		if (item->v_node->n_type != BSHELL_AST_CMDCALL) {
+			compile_value_load(ctx, item);
+		}
+		compile_value_destroy(item);
+	}
+
+	compile_push_value(ctx, &pipeline_type, src);
+	return COMPILE_OK(0);
+}