llvm/lib/TextAPI/Utils.cpp

   1 //===- Utils.cpp ----------------------------------------------------------===//
   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 // Implements utility functions for TextAPI Darwin operations.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "llvm/TextAPI/Utils.h"
  14 #include "llvm/ADT/StringExtras.h"
  15 #include "llvm/TextAPI/TextAPIError.h"
  16
  17 using namespace llvm;
  18 using namespace llvm::MachO;
  19
  20 void llvm::MachO::replace_extension(SmallVectorImpl<char> &Path,
  21                                     const Twine &Extension) {
  22   StringRef P(Path.begin(), Path.size());
  23   auto ParentPath = sys::path::parent_path(P);
  24   auto Filename = sys::path::filename(P);
  25
  26   if (!ParentPath.ends_with(Filename.str() + ".framework")) {
  27     sys::path::replace_extension(Path, Extension);
  28     return;
  29   }
  30   // Framework dylibs do not have a file extension, in those cases the new
  31   // extension is appended. e.g. given Path: "Foo.framework/Foo" and Extension:
  32   // "tbd", the result is "Foo.framework/Foo.tbd".
  33   SmallString<8> Storage;
  34   StringRef Ext = Extension.toStringRef(Storage);
  35
  36   // Append '.' if needed.
  37   if (!Ext.empty() && Ext[0] != '.')
  38     Path.push_back('.');
  39
  40   // Append extension.
  41   Path.append(Ext.begin(), Ext.end());
  42 }
  43
  44 std::error_code llvm::MachO::shouldSkipSymLink(const Twine &Path,
  45                                                bool &Result) {
  46   Result = false;
  47   SmallString<PATH_MAX> Storage;
  48   auto P = Path.toNullTerminatedStringRef(Storage);
  49   sys::fs::file_status Stat1;
  50   auto EC = sys::fs::status(P.data(), Stat1);
  51   if (EC == std::errc::too_many_symbolic_link_levels) {
  52     Result = true;
  53     return {};
  54   }
  55
  56   if (EC)
  57     return EC;
  58
  59   StringRef Parent = sys::path::parent_path(P);
  60   while (!Parent.empty()) {
  61     sys::fs::file_status Stat2;
  62     if (auto ec = sys::fs::status(Parent, Stat2))
  63       return ec;
  64
  65     if (sys::fs::equivalent(Stat1, Stat2)) {
  66       Result = true;
  67       return {};
  68     }
  69
  70     Parent = sys::path::parent_path(Parent);
  71   }
  72   return {};
  73 }
  74
  75 std::error_code
  76 llvm::MachO::make_relative(StringRef From, StringRef To,
  77                            SmallVectorImpl<char> &RelativePath) {
  78   SmallString<PATH_MAX> Src = From;
  79   SmallString<PATH_MAX> Dst = To;
  80   if (auto EC = sys::fs::make_absolute(Src))
  81     return EC;
  82
  83   if (auto EC = sys::fs::make_absolute(Dst))
  84     return EC;
  85
  86   SmallString<PATH_MAX> Result;
  87   Src = sys::path::parent_path(From);
  88   auto IT1 = sys::path::begin(Src), IT2 = sys::path::begin(Dst),
  89        IE1 = sys::path::end(Src), IE2 = sys::path::end(Dst);
  90   // Ignore the common part.
  91   for (; IT1 != IE1 && IT2 != IE2; ++IT1, ++IT2) {
  92     if (*IT1 != *IT2)
  93       break;
  94   }
  95
  96   for (; IT1 != IE1; ++IT1)
  97     sys::path::append(Result, "../");
  98
  99   for (; IT2 != IE2; ++IT2)
 100     sys::path::append(Result, *IT2);
 101
 102   if (Result.empty())
 103     Result = ".";
 104
 105   RelativePath.swap(Result);
 106
 107   return {};
 108 }
 109
 110 bool llvm::MachO::isPrivateLibrary(StringRef Path, bool IsSymLink) {
 111   // Remove the iOSSupport and DriverKit prefix to identify public locations.
 112   Path.consume_front(MACCATALYST_PREFIX_PATH);
 113   Path.consume_front(DRIVERKIT_PREFIX_PATH);
 114   // Also /Library/Apple prefix for ROSP.
 115   Path.consume_front("/Library/Apple");
 116
 117   if (Path.starts_with("/usr/local/lib"))
 118     return true;
 119
 120   if (Path.starts_with("/System/Library/PrivateFrameworks"))
 121     return true;
 122
 123   // Everything in /usr/lib/swift (including sub-directories) are considered
 124   // public.
 125   if (Path.consume_front("/usr/lib/swift/"))
 126     return false;
 127
 128   // Only libraries directly in /usr/lib are public. All other libraries in
 129   // sub-directories are private.
 130   if (Path.consume_front("/usr/lib/"))
 131     return Path.contains('/');
 132
 133   // "/System/Library/Frameworks/" is a public location.
 134   if (Path.starts_with("/System/Library/Frameworks/")) {
 135     StringRef Name, Rest;
 136     std::tie(Name, Rest) =
 137         Path.drop_front(sizeof("/System/Library/Frameworks")).split('.');
 138
 139     // Allow symlinks to top-level frameworks.
 140     if (IsSymLink && Rest == "framework")
 141       return false;
 142
 143     // Only top level framework are public.
 144     // /System/Library/Frameworks/Foo.framework/Foo ==> true
 145     // /System/Library/Frameworks/Foo.framework/Versions/A/Foo ==> true
 146     // /System/Library/Frameworks/Foo.framework/Resources/libBar.dylib ==> false
 147     // /System/Library/Frameworks/Foo.framework/Frameworks/Bar.framework/Bar
 148     // ==> false
 149     // /System/Library/Frameworks/Foo.framework/Frameworks/Xfoo.framework/XFoo
 150     // ==> false
 151     return !(Rest.starts_with("framework/") &&
 152              (Rest.ends_with(Name) || Rest.ends_with((Name + ".tbd").str()) ||
 153               (IsSymLink && Rest.ends_with("Current"))));
 154   }
 155   return false;
 156 }
 157
 158 static StringLiteral RegexMetachars = "()^$|+.[]\\{}";
 159
 160 llvm::Expected<Regex> llvm::MachO::createRegexFromGlob(StringRef Glob) {
 161   SmallString<128> RegexString("^");
 162   unsigned NumWildcards = 0;
 163   for (unsigned i = 0; i < Glob.size(); ++i) {
 164     char C = Glob[i];
 165     switch (C) {
 166     case '?':
 167       RegexString += '.';
 168       break;
 169     case '*': {
 170       const char *PrevChar = i > 0 ? Glob.data() + i - 1 : nullptr;
 171       NumWildcards = 1;
 172       ++i;
 173       while (i < Glob.size() && Glob[i] == '*') {
 174         ++NumWildcards;
 175         ++i;
 176       }
 177       const char *NextChar = i < Glob.size() ? Glob.data() + i : nullptr;
 178
 179       if ((NumWildcards > 1) && (PrevChar == nullptr || *PrevChar == '/') &&
 180           (NextChar == nullptr || *NextChar == '/')) {
 181         RegexString += "(([^/]*(/|$))*)";
 182       } else
 183         RegexString += "([^/]*)";
 184       break;
 185     }
 186     default:
 187       if (RegexMetachars.find(C) != StringRef::npos)
 188         RegexString.push_back('\\');
 189       RegexString.push_back(C);
 190     }
 191   }
 192   RegexString.push_back('$');
 193   if (NumWildcards == 0)
 194     return make_error<StringError>("not a glob", inconvertibleErrorCode());
 195
 196   llvm::Regex Rule = Regex(RegexString);
 197   std::string Error;
 198   if (!Rule.isValid(Error))
 199     return make_error<StringError>(Error, inconvertibleErrorCode());
 200
 201   return std::move(Rule);
 202 }
 203
 204 Expected<AliasMap>
 205 llvm::MachO::parseAliasList(std::unique_ptr<llvm::MemoryBuffer> &Buffer) {
 206   SmallVector<StringRef, 16> Lines;
 207   AliasMap Aliases;
 208   Buffer->getBuffer().split(Lines, "\n", /*MaxSplit=*/-1,
 209                             /*KeepEmpty=*/false);
 210   for (const StringRef Line : Lines) {
 211     StringRef L = Line.trim();
 212     if (L.empty())
 213       continue;
 214     // Skip comments.
 215     if (L.starts_with("#"))
 216       continue;
 217     StringRef Symbol, Remain, Alias;
 218     // Base symbol is seperated by whitespace.
 219     std::tie(Symbol, Remain) = getToken(L);
 220     // The Alias symbol ends before a comment or EOL.
 221     std::tie(Alias, Remain) = getToken(Remain, "#");
 222     Alias = Alias.trim();
 223     if (Alias.empty())
 224       return make_error<TextAPIError>(
 225           TextAPIError(TextAPIErrorCode::InvalidInputFormat,
 226                        ("missing alias for: " + Symbol).str()));
 227     SimpleSymbol AliasSym = parseSymbol(Alias);
 228     SimpleSymbol BaseSym = parseSymbol(Symbol);
 229     Aliases[{AliasSym.Name.str(), AliasSym.Kind}] = {BaseSym.Name.str(),
 230                                                      BaseSym.Kind};
 231   }
 232
 233   return Aliases;
 234 }