From b9c806b9e3631d76b8ceaa6208497aba60c75f83 Mon Sep 17 00:00:00 2001
From: Noel Grandin <noel.grandin@collabora.co.uk>
Date: Thu, 14 Apr 2022 18:52:19 +0200
Subject: [PATCH] address potential find/rfind failures

in the conversion in
    commit 74957c7d2f3697fbf2b6f4d6a31c61d5d7df039b
    Author: Noel Grandin <noel.grandin@collabora.co.uk>
    Date:   Wed Apr 13 13:54:22 2022 +0200
    use more string_view in l10ntools

where the prior code might have been relying on the -1 returned by
indexOf and lastIndexOd

Change-Id: Ief5dedccbaf4e14e5f59aa3c2f7481ff0bb7e2e8
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/133027
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
---
 l10ntools/source/merge.cxx | 13 +++++++++----
 l10ntools/source/po.cxx    |  5 ++++-
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/l10ntools/source/merge.cxx b/l10ntools/source/merge.cxx
index 8a6964c61fa4..588cb73d8614 100644
--- a/l10ntools/source/merge.cxx
+++ b/l10ntools/source/merge.cxx
@@ -34,10 +34,15 @@ namespace
 {
     OString lcl_NormalizeFilename(std::string_view rFilename)
     {
-        return OString(rFilename.substr(
-            std::max(
-                rFilename.rfind( '\\' ),
-                rFilename.rfind( '/' ))+1));
+        size_t idx1 = rFilename.rfind( '\\' );
+        size_t idx2 = rFilename.rfind( '/' );
+        if (idx1 == std::string_view::npos && idx2 == std::string_view::npos)
+            return OString(rFilename);
+        if (idx1 == std::string_view::npos)
+            idx1 = 0;
+        if (idx2 == std::string_view::npos)
+            idx2 = 0;
+        return OString(rFilename.substr(std::max(idx1, idx2)+1));
     };
 
     bool lcl_ReadPoChecked(
diff --git a/l10ntools/source/po.cxx b/l10ntools/source/po.cxx
index b93126838c99..62d09e1e7407 100644
--- a/l10ntools/source/po.cxx
+++ b/l10ntools/source/po.cxx
@@ -257,7 +257,10 @@ PoEntry::PoEntry(
         throw WRONGHELPTEXT;
 
     m_pGenPo.reset( new GenPoEntry() );
-    OString sReference(rSourceFile.substr(rSourceFile.rfind('/')+1));
+    size_t idx = rSourceFile.rfind('/');
+    if (idx == std::string_view::npos)
+        idx = 0;
+    OString sReference(rSourceFile.substr(idx+1));
     m_pGenPo->setReference(sReference);
 
     OString sMsgCtxt =