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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file contains functions used for auto conversion between 10 // ASCII/EBCDIC codepages specific to z/OS. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifdef __MVS__ 15 16 #include "llvm/Support/AutoConvert.h" 17 #include "llvm/Support/Error.h" 18 #include <cassert> 19 #include <fcntl.h> 20 #include <sys/stat.h> 21 #include <unistd.h> 22 23 using namespace llvm; 24 25 static int savedStdHandleAutoConversionMode[3] = {-1, -1, -1}; 26 27 int disablezOSAutoConversion(int FD) { 28 static const struct f_cnvrt Convert = { 29 SETCVTOFF, // cvtcmd 30 0, // pccsid 31 0, // fccsid 32 }; 33 34 return fcntl(FD, F_CONTROL_CVT, &Convert); 35 } 36 37 int restorezOSStdHandleAutoConversion(int FD) { 38 assert(FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO); 39 if (savedStdHandleAutoConversionMode[FD] == -1) 40 return 0; 41 struct f_cnvrt Cvt = { 42 savedStdHandleAutoConversionMode[FD], // cvtcmd 43 0, // pccsid 44 0, // fccsid 45 }; 46 return (fcntl(FD, F_CONTROL_CVT, &Cvt)); 47 } 48 49 int enablezOSAutoConversion(int FD) { 50 struct f_cnvrt Query = { 51 QUERYCVT, // cvtcmd 52 0, // pccsid 53 0, // fccsid 54 }; 55 56 if (fcntl(FD, F_CONTROL_CVT, &Query) == -1) 57 return -1; 58 59 // We don't need conversion for UTF-8 tagged files. 60 // TODO: Remove the assumption of ISO8859-1 = UTF-8 here when we fully resolve 61 // problems related to UTF-8 tagged source files. 62 // When the pccsid is not ISO8859-1, autoconversion is still needed. 63 if (Query.pccsid == CCSID_ISO8859_1 && 64 (Query.fccsid == CCSID_UTF_8 || Query.fccsid == CCSID_ISO8859_1)) 65 return 0; 66 67 // Save the state of std handles before we make changes to it. 68 if ((FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO) && 69 savedStdHandleAutoConversionMode[FD] == -1) 70 savedStdHandleAutoConversionMode[FD] = Query.cvtcmd; 71 72 if (FD == STDOUT_FILENO || FD == STDERR_FILENO) 73 Query.cvtcmd = SETCVTON; 74 else 75 Query.cvtcmd = SETCVTALL; 76 77 Query.pccsid = 78 (FD == STDIN_FILENO || FD == STDOUT_FILENO || FD == STDERR_FILENO) 79 ? 0 80 : CCSID_UTF_8; 81 // Assume untagged files to be IBM-1047 encoded. 82 Query.fccsid = (Query.fccsid == FT_UNTAGGED) ? CCSID_IBM_1047 : Query.fccsid; 83 return fcntl(FD, F_CONTROL_CVT, &Query); 84 } 85 86 std::error_code llvm::disablezOSAutoConversion(int FD) { 87 if (::disablezOSAutoConversion(FD) == -1) 88 return errnoAsErrorCode(); 89 90 return std::error_code(); 91 } 92 93 std::error_code llvm::enablezOSAutoConversion(int FD) { 94 if (::enablezOSAutoConversion(FD) == -1) 95 return errnoAsErrorCode(); 96 97 return std::error_code(); 98 } 99 100 std::error_code llvm::restorezOSStdHandleAutoConversion(int FD) { 101 if (::restorezOSStdHandleAutoConversion(FD) == -1) 102 return errnoAsErrorCode(); 103 104 return std::error_code(); 105 } 106 107 std::error_code llvm::setzOSFileTag(int FD, int CCSID, bool Text) { 108 assert((!Text || (CCSID != FT_UNTAGGED && CCSID != FT_BINARY)) && 109 "FT_UNTAGGED and FT_BINARY are not allowed for text files"); 110 struct file_tag Tag; 111 Tag.ft_ccsid = CCSID; 112 Tag.ft_txtflag = Text; 113 Tag.ft_deferred = 0; 114 Tag.ft_rsvflags = 0; 115 116 if (fcntl(FD, F_SETTAG, &Tag) == -1) 117 return errnoAsErrorCode(); 118 return std::error_code(); 119 } 120 121 ErrorOr<__ccsid_t> llvm::getzOSFileTag(const char *FileName, const int FD) { 122 // If we have a file descriptor, use it to find out file tagging. Otherwise we 123 // need to use stat() with the file path. 124 if (FD != -1) { 125 struct f_cnvrt Query = { 126 QUERYCVT, // cvtcmd 127 0, // pccsid 128 0, // fccsid 129 }; 130 if (fcntl(FD, F_CONTROL_CVT, &Query) == -1) 131 return std::error_code(errno, std::generic_category()); 132 return Query.fccsid; 133 } 134 struct stat Attr; 135 if (stat(FileName, &Attr) == -1) 136 return std::error_code(errno, std::generic_category()); 137 return Attr.st_tag.ft_ccsid; 138 } 139 140 ErrorOr<bool> llvm::needzOSConversion(const char *FileName, const int FD) { 141 ErrorOr<__ccsid_t> Ccsid = getzOSFileTag(FileName, FD); 142 if (std::error_code EC = Ccsid.getError()) 143 return EC; 144 // We don't need conversion for UTF-8 tagged files or binary files. 145 // TODO: Remove the assumption of ISO8859-1 = UTF-8 here when we fully resolve 146 // problems related to UTF-8 tagged source files. 147 switch (*Ccsid) { 148 case CCSID_UTF_8: 149 case CCSID_ISO8859_1: 150 case FT_BINARY: 151 return false; 152 default: 153 return true; 154 } 155 } 156 157 #endif //__MVS__ 158