From 757c91e2de250b69f27843b01ab9b8c7deb5a045 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Sat, 9 Mar 2019 15:47:28 +0000
Subject: [PATCH] Extra ptrlen function, ptrlen_endswith().

Identical to ptrlen_startswith(), only the other way round.
---
 misc.h  |  1 +
 utils.c | 14 ++++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/misc.h b/misc.h
index f2919af3..25ac6d15 100644
--- a/misc.h
+++ b/misc.h
@@ -169,6 +169,7 @@ bool ptrlen_eq_string(ptrlen pl, const char *str);
 bool ptrlen_eq_ptrlen(ptrlen pl1, ptrlen pl2);
 int ptrlen_strcmp(ptrlen pl1, ptrlen pl2);
 bool ptrlen_startswith(ptrlen whole, ptrlen prefix, ptrlen *tail);
+bool ptrlen_endswith(ptrlen whole, ptrlen suffix, ptrlen *tail);
 char *mkstr(ptrlen pl);
 int string_length_for_printf(size_t);
 /* Derive two printf arguments from a ptrlen, suitable for "%.*s" */
diff --git a/utils.c b/utils.c
index a85a5d29..96024d2f 100644
--- a/utils.c
+++ b/utils.c
@@ -924,6 +924,20 @@ bool ptrlen_startswith(ptrlen whole, ptrlen prefix, ptrlen *tail)
     return false;
 }
 
+bool ptrlen_endswith(ptrlen whole, ptrlen suffix, ptrlen *tail)
+{
+    if (whole.len >= suffix.len &&
+        !memcmp((char *)whole.ptr + (whole.len - suffix.len),
+                suffix.ptr, suffix.len)) {
+        if (tail) {
+            tail->ptr = whole.ptr;
+            tail->len = whole.len - suffix.len;
+        }
+        return true;
+    }
+    return false;
+}
+
 char *mkstr(ptrlen pl)
 {
     char *p = snewn(pl.len + 1, char);