Add a minimal read_line implementationv0.1

2 files changed, 42 insertions, 3 deletions

diff --git a/src/bootstrap/main.c b/src/bootstrap/main.c
index b5fd821..662831e 100755
--- a/src/bootstrap/main.c
+++ b/src/bootstrap/main.c
@@ -4,6 +4,7 @@
 #include <stdlib.h>
 
 #include "string_view.c"
+#include "read_line.c"
 
 void
 process_source(const StringView *source) {
@@ -14,11 +15,17 @@ process_source(const StringView *source) {
 
 void
 run_repl(void) {
-    printf("BDL REPL (Press Ctrl-C to exit)\n");
+    printf("BDL REPL (Press Ctrl-D or Ctrl-C to exit)\n");
     while (true) {
         printf(REPL_PROMPT);
-        getchar();
-        process_source(NULL);
+        StringView sv = read_line();
+        if (sv.start == NULL) {
+            return;
+        }
+        process_source(&sv);
+        if (sv.n != 0) {
+            printf("\n");
+        }
     }
 }
 
diff --git a/src/bootstrap/read_line.c b/src/bootstrap/read_line.c
new file mode 100644
index 0000000..7612d05
--- /dev/null
+++ b/src/bootstrap/read_line.c
@@ -0,0 +1,32 @@
+#define RL_BUF_SIZE 1024
+static char readline_buf[RL_BUF_SIZE];
+
+StringView
+read_line(void) {
+    // Clear buffer.
+    for (size_t i = 0; i < RL_BUF_SIZE; i++) {
+        readline_buf[i] = 0;
+    }
+
+    // Barebones readline implementation.
+    size_t n = 0;
+    char c;
+    while ((c = getchar()) != '\n') {
+        if (c == '\b') {
+            readline_buf[n] = '\0';
+            n--;
+        } else if (c == EOF || c == '\0') {
+            return (StringView){ .start = NULL, .n = 0 };
+        } else if ((c >= ' ' && c <= '~') && n < RL_BUF_SIZE) {
+            readline_buf[n] = c;
+            n++;
+        }
+    }
+
+    StringView sv = (StringView){
+        .start = (char *)&readline_buf,
+        .n = n,
+    };
+    return sv;
+}
+