add more documentation

1 files changed, 24 insertions, 7 deletions

diff --git a/src/main.c b/src/main.c
index 884a198..cbf7f34 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,5 +1,6 @@
 #include <builtins.h>
 #include <dlfcn.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stem.h>
@@ -13,17 +14,38 @@ extern array_t *EVAL_STACK;
 extern ht_t *OBJ_TABLE;
 extern ht_t *FLIT;
 
+/*! prints usage then exits */
 void usage() {
   printf("Usage: stem [-hv] [file]\n");
   exit(1);
 }
 
+/*! prints version and exits */
 void version() {
   printf("Author: Preston Pan, MIT License 2023\n");
   printf("stem, version 1.2 alpha\n");
   exit(0);
 }
 
+/*! frees all global variables */
+void global_free() {
+  free(PARSER->source);
+  ht_free(WORD_TABLE, value_free);
+  ht_free(FLIT, func_free);
+  ht_free(OBJ_TABLE, custom_free);
+  array_free(STACK);
+  free(PARSER);
+  array_free(EVAL_STACK);
+}
+
+/*! handles SIGINT signal; frees memory before exit */
+void sigint_handler(int signum) {
+  signal(SIGINT, sigint_handler);
+  global_free();
+  fflush(stdout);
+  exit(1);
+}
+
 int main(int argc, char **argv) {
   value_t *v;
   size_t len;
@@ -59,6 +81,7 @@ int main(int argc, char **argv) {
   OBJ_TABLE = init_ht(500);
 
   add_funcs();
+  signal(SIGINT, sigint_handler);
 
   /* parse and eval loop */
   while (1) {
@@ -69,12 +92,6 @@ int main(int argc, char **argv) {
   }
 
   /* Free all global variables */
-  free(PARSER->source);
-  ht_free(WORD_TABLE, value_free);
-  ht_free(FLIT, func_free);
-  ht_free(OBJ_TABLE, custom_free);
-  array_free(STACK);
-  free(PARSER);
-  array_free(EVAL_STACK);
+  global_free();
   return 0;
 }