From 6dd02a5d6e421e2cbe901de8103e5f2dab38ade7 Mon Sep 17 00:00:00 2001
From: Jesse McDonald <nybble41@gmail.com>
Date: Mon, 12 Apr 2010 14:08:34 -0500
Subject: [PATCH] Stop reading at EOF, and signal an error when EOF occurs
 inside a string.

---
 reader.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

diff --git a/reader.c b/reader.c
index 8a5e8b3..6d83803 100644
--- a/reader.c
+++ b/reader.c
@@ -489,6 +489,8 @@ static value_t read_string(reader_state_t *state)
     bool skip_ws = false;
     char ch;
 
+    release_assert(state->ch != EOF);
+
     if ((buffer_size - length) < 1)
     {
       release_assert(buffer_size <= INT32_MAX / 3);
@@ -551,7 +553,10 @@ static value_t read_string(reader_state_t *state)
         /* Treats everything that follows on the same line as a comment,
          * and additionally skips leading whitespace on the next line. */
         while (state->ch != '\n')
+        {
+          release_assert(state->ch != EOF);
           next_char(state);
+        }
         skip_ws = true;
         break;
       case '\\': ch = '\\'; next_char(state); break;
@@ -870,16 +875,19 @@ static void tree_replace(value_t *in, value_t oldval, value_t newval)
 
 static void next_char(reader_state_t *state)
 {
-  state->ch = fgetc(state->file);
+  if (state->ch != EOF)
+  {
+    state->ch = fgetc(state->file);
 
-  if (state->ch == '\n')
-  {
-    ++state->line;
-    state->column = 0;
-  }
-  else
-  {
-    ++state->column;
+    if (state->ch == '\n')
+    {
+      ++state->line;
+      state->column = 0;
+    }
+    else
+    {
+      ++state->column;
+    }
   }
 }