From 7f77e6f4f20c6369426b47cf83d950d2875c2ea8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jan=20Kr=C3=BCger?= <jk@jk.gs>
Date: Thu, 26 May 2011 09:02:36 +0200
Subject: [PATCH] Suppress non-critical PHP errors

The previous code contained various pieces that PHP usually executes
without complaints, but on some PHP installations it emits warnings.
This adds more checks that pretty much do what PHP would do anyway, but
without generating any errors.
---
 gen.php   | 7 ++++---
 get.php   | 2 +-
 index.php | 2 +-
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/gen.php b/gen.php
index 104a34f..4f77c77 100644
--- a/gen.php
+++ b/gen.php
@@ -1,8 +1,8 @@
 <?php
 
-$type = $_POST['type'];
-$def = $_POST['def'];
-$private = $_POST['private'] ? 1 : 0;
+$type = isset($_POST['type']) ? $_POST['type'] : NULL;
+$def = isset($_POST['def']) ? $_POST['def'] : NULL;
+$private = isset($_POST['private']) ? ($_POST['private'] ? 1 : 0) : 0;
 
 if ($type != 'graph' && $type != 'digraph')
 	die("Nuh-uh. Use one of the checkboxes.");
@@ -20,6 +20,7 @@ function get_one($q)
 {
 	$res = mysql_query($q);
 	if (!$res) die("Failed to get stuff from database. Sorry!");
+	if (mysql_num_rows($res) == 0) return NULL;
 	return mysql_result($res, 0);
 }
 function id_shorten($id)
diff --git a/get.php b/get.php
index a145d08..fd6ba39 100644
--- a/get.php
+++ b/get.php
@@ -16,7 +16,7 @@ function id_lengthen($id)
 	return $res;
 }
 
-$id = $_GET['id'];
+$id = isset($_GET['id']) ? $_GET['id'] : NULL;
 if (!$id) die("No ID given.");
 if (strlen($id) == 40)
 	$q = "graph_code = '".mysql_real_escape_string($id)."'";
diff --git a/index.php b/index.php
index c53307d..0f8b3e0 100644
--- a/index.php
+++ b/index.php
@@ -17,7 +17,7 @@
 <p>Definition (without the surrounding <code>[di]graph {}</code> thing): (<a
 href="http://en.wikipedia.org/wiki/DOT_language">syntax</a>, <a
 href="index.php?example=1">example</a>)<br>
-<textarea name="def" rows="20" cols="50"><?php if ($_GET['example']):
+<textarea name="def" rows="20" cols="50"><?php if (isset($_GET['example']) && $_GET['example']):
 ?>Sleep -&gt; Work [label="zombie"]
 Work -&gt; TV [label="zombie"]
 TV -&gt; Sleep [label="zombie"]