Merge topic '16607-error-out-on-non-seekable-input-files'

ded616bd cmListFileLexer: bail out on seek-errors

3 files changed, 14 insertions, 2 deletions

diff --git a/Source/cmListFileCache.cxx b/Source/cmListFileCache.cxx
index b1cd889..23b666e 100644
--- a/Source/cmListFileCache.cxx
+++ b/Source/cmListFileCache.cxx
@@ -80,6 +80,13 @@ bool cmListFileParser::ParseFile()
     return false;
   }
 
+  if (bom == cmListFileLexer_BOM_Broken) {
+    cmListFileLexer_SetFileName(this->Lexer, CM_NULLPTR, CM_NULLPTR);
+    this->IssueFileOpenError("Error while reading Byte-Order-Mark. "
+                             "File not seekable?");
+    return false;
+  }
+
   // Verify the Byte-Order-Mark, if any.
   if (bom != cmListFileLexer_BOM_None && bom != cmListFileLexer_BOM_UTF8) {
     cmListFileLexer_SetFileName(this->Lexer, CM_NULLPTR, CM_NULLPTR);
diff --git a/Source/cmListFileLexer.c b/Source/cmListFileLexer.c
index 56559f6..44d0894 100644
--- a/Source/cmListFileLexer.c
+++ b/Source/cmListFileLexer.c
@@ -2559,11 +2559,15 @@ static cmListFileLexer_BOM cmListFileLexer_ReadBOM(FILE* f)
       if (fread(b, 1, 2, f) == 2 && b[0] == 0 && b[1] == 0) {
         return cmListFileLexer_BOM_UTF32LE;
       }
-      fsetpos(f, &p);
+      if (fsetpos(f, &p) != 0) {
+        return cmListFileLexer_BOM_Broken;
+      }
       return cmListFileLexer_BOM_UTF16LE;
     }
   }
-  rewind(f);
+  if (fseek(f, 0, SEEK_SET) != 0) {
+    return cmListFileLexer_BOM_Broken;
+  }
   return cmListFileLexer_BOM_None;
 }
 
diff --git a/Source/cmListFileLexer.h b/Source/cmListFileLexer.h
index c9fb6da..f243010a 100644
--- a/Source/cmListFileLexer.h
+++ b/Source/cmListFileLexer.h
@@ -32,6 +32,7 @@ struct cmListFileLexer_Token_s
 enum cmListFileLexer_BOM_e
 {
   cmListFileLexer_BOM_None,
+  cmListFileLexer_BOM_Broken,
   cmListFileLexer_BOM_UTF8,
   cmListFileLexer_BOM_UTF16BE,
   cmListFileLexer_BOM_UTF16LE,