136 lines · cpp
1//===- AutoConvert.cpp - Auto conversion between ASCII/EBCDIC -------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file contains functions used for auto conversion between10// ASCII/EBCDIC codepages specific to z/OS.11//12//===----------------------------------------------------------------------===//13 14#ifdef __MVS__15 16#include "llvm/Support/AutoConvert.h"17#include <cassert>18#include <fcntl.h>19#include <sys/stat.h>20#include <unistd.h>21 22using namespace llvm;23 24static int savedStdHandleAutoConversionMode[3] = {-1, -1, -1};25 26int disablezOSAutoConversion(int FD) {27 static const struct f_cnvrt Convert = {28 SETCVTOFF, // cvtcmd29 0, // pccsid30 0, // fccsid31 };32 33 return fcntl(FD, F_CONTROL_CVT, &Convert);34}35 36int restorezOSStdHandleAutoConversion(int FD) {37 assert(FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO);38 if (savedStdHandleAutoConversionMode[FD] == -1)39 return 0;40 struct f_cnvrt Cvt = {41 savedStdHandleAutoConversionMode[FD], // cvtcmd42 0, // pccsid43 0, // fccsid44 };45 return (fcntl(FD, F_CONTROL_CVT, &Cvt));46}47 48int enablezOSAutoConversion(int FD) {49 struct f_cnvrt Query = {50 QUERYCVT, // cvtcmd51 0, // pccsid52 0, // fccsid53 };54 55 if (fcntl(FD, F_CONTROL_CVT, &Query) == -1)56 return -1;57 58 // We don't need conversion for UTF-8 tagged files.59 // TODO: Remove the assumption of ISO8859-1 = UTF-8 here when we fully resolve60 // problems related to UTF-8 tagged source files.61 // When the pccsid is not ISO8859-1, autoconversion is still needed.62 if (Query.pccsid == CCSID_ISO8859_1 &&63 (Query.fccsid == CCSID_UTF_8 || Query.fccsid == CCSID_ISO8859_1))64 return 0;65 66 // Save the state of std handles before we make changes to it.67 if ((FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO) &&68 savedStdHandleAutoConversionMode[FD] == -1)69 savedStdHandleAutoConversionMode[FD] = Query.cvtcmd;70 71 if (FD == STDOUT_FILENO || FD == STDERR_FILENO)72 Query.cvtcmd = SETCVTON;73 else74 Query.cvtcmd = SETCVTALL;75 76 Query.pccsid =77 (FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO)78 ? 079 : CCSID_UTF_8;80 // Assume untagged files to be IBM-1047 encoded.81 Query.fccsid = (Query.fccsid == FT_UNTAGGED) ? CCSID_IBM_1047 : Query.fccsid;82 return fcntl(FD, F_CONTROL_CVT, &Query);83}84 85std::error_code llvm::setzOSFileTag(int FD, int CCSID, bool Text) {86 assert((!Text || (CCSID != FT_UNTAGGED && CCSID != FT_BINARY)) &&87 "FT_UNTAGGED and FT_BINARY are not allowed for text files");88 struct file_tag Tag;89 Tag.ft_ccsid = CCSID;90 Tag.ft_txtflag = Text;91 Tag.ft_deferred = 0;92 Tag.ft_rsvflags = 0;93 94 if (fcntl(FD, F_SETTAG, &Tag) == -1)95 return errnoAsErrorCode();96 return std::error_code();97}98 99ErrorOr<__ccsid_t> llvm::getzOSFileTag(const Twine &FileName, const int FD) {100 // If we have a file descriptor, use it to find out file tagging. Otherwise we101 // need to use stat() with the file path.102 if (FD != -1) {103 struct f_cnvrt Query = {104 QUERYCVT, // cvtcmd105 0, // pccsid106 0, // fccsid107 };108 if (fcntl(FD, F_CONTROL_CVT, &Query) == -1)109 return std::error_code(errno, std::generic_category());110 return Query.fccsid;111 }112 struct stat Attr;113 if (stat(FileName.str().c_str(), &Attr) == -1)114 return std::error_code(errno, std::generic_category());115 return Attr.st_tag.ft_ccsid;116}117 118ErrorOr<bool> llvm::needzOSConversion(const Twine &FileName, const int FD) {119 ErrorOr<__ccsid_t> Ccsid = getzOSFileTag(FileName, FD);120 if (std::error_code EC = Ccsid.getError())121 return EC;122 // We don't need conversion for UTF-8 tagged files or binary files.123 // TODO: Remove the assumption of ISO8859-1 = UTF-8 here when we fully resolve124 // problems related to UTF-8 tagged source files.125 switch (*Ccsid) {126 case CCSID_UTF_8:127 case CCSID_ISO8859_1:128 case FT_BINARY:129 return false;130 default:131 return true;132 }133}134 135#endif //__MVS__136