[PATCH olang v1 1/3] scope: create scope data structure

[Johnny Richard <johnny@johnnyrichard.com>]

Signed-off-by: Johnny Richard <johnny@johnnyrichard.com>
---
 src/scope.c | 101 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/scope.h |  54 ++++++++++++++++++++++++++++
 2 files changed, 155 insertions(+)
 create mode 100644 src/scope.c
 create mode 100644 src/scope.h

diff --git a/src/scope.c b/src/scope.c
new file mode 100644
index 0000000..3271856
--- /dev/null
+++ b/src/scope.c
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2024 olang maintainers
+ *
+ * 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 <https://www.gnu.org/licenses/>.
+ */
+#include <assert.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "scope.h"
+
+scope_t *
+scope_new(arena_t *arena)
+{
+    assert(arena);
+    scope_t *scope = (scope_t *)arena_alloc(arena, sizeof(scope_t));
+    if (scope == NULL) {
+        fprintf(stderr, "[FATAL] Out of memory: scope_new: %s\n", strerror(errno));
+        exit(EXIT_FAILURE);
+    }
+    scope->arena = arena;
+    scope->symbols = map_new(arena);
+    return scope;
+}
+
+symbol_t *
+symbol_new(arena_t *arena, string_view_t id)
+{
+    assert(arena);
+    symbol_t *symbol = (symbol_t *)arena_alloc(arena, sizeof(symbol_t));
+    if (symbol == NULL) {
+        fprintf(stderr, "[FATAL] Out of memory: symbol_new: %s\n", strerror(errno));
+        exit(EXIT_FAILURE);
+    }
+    symbol->id = id;
+    return symbol;
+}
+
+symbol_t *
+scope_lookup(scope_t *scope, string_view_t id)
+{
+    assert(scope);
+    while (scope != NULL) {
+
+        char cstr_id[id.size + 1];
+        cstr_id[id.size] = 0;
+        memcpy(cstr_id, id.chars, id.size);
+
+        symbol_t *symbol = (symbol_t *)map_get(scope->symbols, cstr_id);
+        if (symbol != NULL) {
+            return symbol;
+        }
+        scope = scope->parent;
+    }
+    return NULL;
+}
+
+void
+scope_insert(scope_t *scope, symbol_t *symbol)
+{
+    assert(scope);
+    assert(symbol);
+
+    char id[symbol->id.size + 1];
+    id[symbol->id.size] = 0;
+    memcpy(id, symbol->id.chars, symbol->id.size);
+
+    map_put(scope->symbols, id, symbol);
+}
+
+scope_t *
+scope_push(scope_t *scope)
+{
+    assert(scope);
+
+    scope_t *child = scope_new(scope->arena);
+    child->parent = scope;
+
+    return child;
+}
+
+scope_t *
+scope_pop(scope_t *scope)
+{
+    assert(scope);
+    assert(scope->parent);
+    return scope->parent;
+}
diff --git a/src/scope.h b/src/scope.h
new file mode 100644
index 0000000..ddb0cd0
--- /dev/null
+++ b/src/scope.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2024 olang maintainers
+ *
+ * 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 <https://www.gnu.org/licenses/>.
+ */
+#ifndef SCOPE_H
+#define SCOPE_H
+
+#include "arena.h"
+#include "map.h"
+#include "string_view.h"
+
+typedef struct symbol
+{
+    string_view_t id;
+} symbol_t;
+
+typedef struct scope
+{
+    struct scope *parent;
+    arena_t *arena;
+    map_t *symbols;
+} scope_t;
+
+scope_t *
+scope_new(arena_t *arena);
+
+symbol_t *
+symbol_new(arena_t *arena, string_view_t id);
+
+symbol_t *
+scope_lookup(scope_t *scope, string_view_t id);
+
+void
+scope_insert(scope_t *scope, symbol_t *symbol);
+
+scope_t *
+scope_push(scope_t *scope);
+
+scope_t *
+scope_pop(scope_t *scope);
+
+#endif /* SCOPE_H */
-- 
2.46.0