Fix full_url() and make email_user report correctly

Changelog.md

@@ -6,6 +6,8 @@ This file holds the changelog for Pepperminty Wiki. This is the master list of t
 ## Fixed
  - [Security] Made the site secret generator cryptographically secure. If you created your wiki before this change, you might want to change your site secret in `peppermint.json` to something more secure with a site like [random.org](https://www.random.org/).
      - The PHP function `openssl_pseudo_random_bytes()` was being used before, but [apparently that's not cryptographically secure](https://paragonie.com/blog/2015/07/how-safely-generate-random-strings-and-integers-in-php).
+ - [Module API] Fix `full_url()` logic
+ - [Module API] Mak  `email_user()` correctly return email sending failures
 
 ## Changed
  - Password hashing has been overhauled! A totally new-and-different system is being used now, so you'll need to rehash all your passwords.

core.php

@@ -169,6 +169,7 @@ function url_origin( $s = false, $use_forwarded_host = false )
  */
 function full_url( $s = false, $use_forwarded_host = false )
 {
+	if($s == false) $s = $_SERVER;
     return url_origin( $s, $use_forwarded_host ) . $s['REQUEST_URI'];
 }
 
@@ -662,6 +663,15 @@ function render_editor($editorName)
 	return "<span class='editor'>&#9998; $editorName</span>";
 }
 
+/**
+ * Saves the settings file back to peppermint.json.
+ * @return bool Whether the settings were saved successfully.
+ */
+function save_settings() {
+	global $paths, $settings;
+	file_put_contents($paths->settings_file, json_encode($settings, JSON_PRETTY_PRINT)) !== false;
+}
+
 /**
  * Saves the currently logged in user's data back to peppermint.json.
  * @package core
@@ -675,9 +685,8 @@ function save_userdata()
 		return false;
 	
 	$settings->users->{$env->user} = $env->user_data;
-	file_put_contents($paths->settings_file, json_encode($settings, JSON_PRETTY_PRINT));
 	
-	return true;
+	return save_settings();
 }
 
 /**
@@ -733,8 +742,7 @@ function email_user($username, $subject, $body)
 	foreach($headers as $header => $value)
 		$compiled_headers .= "$header: $value\r\n";
 	
-	mail($settings->users->{$username}->emailAddress, $subject, $body, $compiled_headers, "-t");
-	return true;
+	return mail($settings->users->{$username}->emailAddress, $subject, $body, $compiled_headers, "-t");
 }
 /**
  * Sends a plain text email to a list of users, replacing {username} with each user's name.