1 files changed, 62 insertions, 11 deletions
diff --git a/contrib/llvm-project/llvm/lib/Support/AutoConvert.cpp b/contrib/llvm-project/llvm/lib/Support/AutoConvert.cpp
index 4fb7e242c348..8170e553ac6e 100644
--- a/contrib/llvm-project/llvm/lib/Support/AutoConvert.cpp
+++ b/contrib/llvm-project/llvm/lib/Support/AutoConvert.cpp
@@ -14,21 +14,36 @@
 #ifdef __MVS__
 
 #include "llvm/Support/AutoConvert.h"
+#include <cassert>
 #include <fcntl.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
-std::error_code llvm::disableAutoConversion(int FD) {
+static int savedStdHandleAutoConversionMode[3] = {-1, -1, -1};
+
+int disableAutoConversion(int FD) {
   static const struct f_cnvrt Convert = {
-      SETCVTOFF,        // cvtcmd
-      0,                // pccsid
-      (short)FT_BINARY, // fccsid
+      SETCVTOFF, // cvtcmd
+      0,         // pccsid
+      0,         // fccsid
   };
-  if (fcntl(FD, F_CONTROL_CVT, &Convert) == -1)
-    return std::error_code(errno, std::generic_category());
-  return std::error_code();
+
+  return fcntl(FD, F_CONTROL_CVT, &Convert);
 }
 
-std::error_code llvm::enableAutoConversion(int FD) {
+int restoreStdHandleAutoConversion(int FD) {
+  assert(FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO);
+  if (savedStdHandleAutoConversionMode[FD] == -1)
+    return 0;
+  struct f_cnvrt Cvt = {
+      savedStdHandleAutoConversionMode[FD], // cvtcmd
+      0,                                    // pccsid
+      0,                                    // fccsid
+  };
+  return (fcntl(FD, F_CONTROL_CVT, &Cvt));
+}
+
+int enableAutoConversion(int FD) {
   struct f_cnvrt Query = {
       QUERYCVT, // cvtcmd
       0,        // pccsid
@@ -36,17 +51,53 @@ std::error_code llvm::enableAutoConversion(int FD) {
   };
 
   if (fcntl(FD, F_CONTROL_CVT, &Query) == -1)
-    return std::error_code(errno, std::generic_category());
+    return -1;
+
+  // We don't need conversion for UTF-8 tagged files.
+  // TODO: Remove the assumption of ISO8859-1 = UTF-8 here when we fully resolve
+  // problems related to UTF-8 tagged source files.
+  // When the pccsid is not ISO8859-1, autoconversion is still needed.
+  if (Query.pccsid == CCSID_ISO8859_1 &&
+      (Query.fccsid == CCSID_UTF_8 || Query.fccsid == CCSID_ISO8859_1))
+    return 0;
+
+  // Save the state of std handles before we make changes to it.
+  if ((FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO) &&
+      savedStdHandleAutoConversionMode[FD] == -1)
+    savedStdHandleAutoConversionMode[FD] = Query.cvtcmd;
+
+  if (FD == STDOUT_FILENO || FD == STDERR_FILENO)
+    Query.cvtcmd = SETCVTON;
+  else
+    Query.cvtcmd = SETCVTALL;
 
-  Query.cvtcmd = SETCVTALL;
   Query.pccsid =
       (FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO)
           ? 0
           : CCSID_UTF_8;
   // Assume untagged files to be IBM-1047 encoded.
   Query.fccsid = (Query.fccsid == FT_UNTAGGED) ? CCSID_IBM_1047 : Query.fccsid;
-  if (fcntl(FD, F_CONTROL_CVT, &Query) == -1)
+  return fcntl(FD, F_CONTROL_CVT, &Query);
+}
+
+std::error_code llvm::disableAutoConversion(int FD) {
+  if (::disableAutoConversion(FD) == -1)
+    return std::error_code(errno, std::generic_category());
+
+  return std::error_code();
+}
+
+std::error_code llvm::enableAutoConversion(int FD) {
+  if (::enableAutoConversion(FD) == -1)
     return std::error_code(errno, std::generic_category());
+
+  return std::error_code();
+}
+
+std::error_code llvm::restoreStdHandleAutoConversion(int FD) {
+  if (::restoreStdHandleAutoConversion(FD) == -1)
+    return std::error_code(errno, std::generic_category());
+
   return std::error_code();
 }