2 files changed, 101 insertions, 7 deletions

diff --git a/include/parse.h b/include/parse.h
index d3cee83..8cc4985 100644
--- a/include/parse.h
+++ b/include/parse.h
@@ -49,6 +49,7 @@ struct ast_const_global {
 
 struct ast_path {
 	const char **segments;
+	int len, cap;
 };
 
 struct ast_import {
@@ -71,14 +72,11 @@ struct ast_toplevel {
 	} decl;
 };
 
-struct ast_subunit {
-	struct ast_import *imports;
-	struct ast_toplevel tops[];
-};
-
 struct ast_unit {
-	struct ast_subunit *root;
-	struct ast_subunit imports[];
+	struct ast_import *imports;
+	struct ast_toplevel *tops;
+	int impsz, implen;
+	int topsz, toplen;
 };
 
 void parse(struct lexer *lexer, struct ast_unit *ast);
diff --git a/src/parse.c b/src/parse.c
index 406752d..a047424 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -1 +1,97 @@
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdnoreturn.h>
 #include "parse.h"
+#include "util.h"
+
+static noreturn void
+error(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vfprintf(stderr, fmt, ap);
+	va_end(ap);
+
+	fprintf(stderr, "\n");
+	exit(EXIT_PARSE);
+}
+
+static void
+append(struct ast_path *path, const char *name)
+{
+	if (path->len >= path->cap) {
+		path->cap *= 2;
+		size_t sz = sizeof(const char *) * path->cap;
+		path->segments = must_realloc(path->segments, sz);
+	}
+
+	path->segments[path->len++] = name;
+}
+
+static bool
+parse_path(struct lexer *lexer, struct ast_path *out)
+{
+	struct token name;
+
+	if (lex(lexer, &name) != T_NAME) {
+		error("syntax error: expected path");
+	}
+
+	out->segments = must_calloc(1, sizeof(const char *));
+	out->segments[0] = name.info.str;
+	out->len = 1;
+	out->cap = 1;
+
+	while (match(lexer, T_MODDELIM)) {
+		if (lex(lexer, &name) != T_NAME) {
+			error("syntax error: expected name");
+		}
+		append(out, name.info.str);
+	}
+
+	return true;
+}
+
+static bool
+parse_import(struct lexer *lexer, struct ast_import *out)
+{
+	if (!match(lexer, T_IMPORT)) {
+		return false;
+	}
+
+	if (!parse_path(lexer, &out->path)) {
+		error("syntax error: expected import path");
+	}
+
+	struct token token;
+	if (lex(lexer, &token) == T_NAME) {
+		out->name = token.info.str;
+	} else {
+		unlex(lexer, &token);
+		out->name = out->path.segments[out->path.len - 1];
+	}
+
+	if (!match(lexer, T_SEMICOLON)) {
+		error("syntax error: expected semicolon");
+	}
+
+	return true;
+}
+
+void
+parse(struct lexer *lexer, struct ast_unit *ast)
+{
+	ast->imports = must_calloc(1, sizeof(struct ast_import));
+	ast->impsz = 1;
+	ast->implen = 0;
+
+	struct ast_import import;
+	while (parse_import(lexer, &import)) {
+		if (ast->implen >= ast->impsz) {
+			ast->impsz *= 2;
+			size_t sz = sizeof(struct ast_import) * ast->impsz;
+			ast->imports = must_realloc(ast->imports, sz);
+		}
+		ast->imports[ast->implen++] = import;
+	}
+}