//===- Strings.cpp -------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include "lld/Common/Strings.h"
#include "lld/Common/ErrorHandler.h"
#include "lld/Common/LLVM.h"
#include "llvm/Demangle/Demangle.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/GlobPattern.h"
#include <algorithm>
#include <mutex>
#include <vector>

using namespace llvm;
using namespace lld;

// Returns the demangled C++ symbol name for name.
std::string lld::demangleItanium(StringRef name) {
  // demangleItanium() can be called for all symbols. Only demangle C++ symbols,
  // to avoid getting unexpected result for a C symbol that happens to match a
  // mangled type name such as "Pi" (which would demangle to "int*").
  if (!name.startswith("_Z") && !name.startswith("__Z") &&
      !name.startswith("___Z") && !name.startswith("____Z"))
    return std::string(name);

  return demangle(std::string(name));
}

SingleStringMatcher::SingleStringMatcher(StringRef Pattern) {
  if (Pattern.size() > 2 && Pattern.startswith("\"") &&
      Pattern.endswith("\"")) {
    ExactMatch = true;
    ExactPattern = Pattern.substr(1, Pattern.size() - 2);
  } else {
    Expected<GlobPattern> Glob = GlobPattern::create(Pattern);
    if (!Glob) {
      error(toString(Glob.takeError()));
      return;
    }
    ExactMatch = false;
    GlobPatternMatcher = *Glob;
  }
}

bool SingleStringMatcher::match(StringRef s) const {
  return ExactMatch ? (ExactPattern == s) : GlobPatternMatcher.match(s);
}

bool StringMatcher::match(StringRef s) const {
  for (const SingleStringMatcher &pat : patterns)
    if (pat.match(s))
      return true;
  return false;
}

// Converts a hex string (e.g. "deadbeef") to a vector.
std::vector<uint8_t> lld::parseHex(StringRef s) {
  std::vector<uint8_t> hex;
  while (!s.empty()) {
    StringRef b = s.substr(0, 2);
    s = s.substr(2);
    uint8_t h;
    if (!to_integer(b, h, 16)) {
      error("not a hexadecimal value: " + b);
      return {};
    }
    hex.push_back(h);
  }
  return hex;
}

// Returns true if S is valid as a C language identifier.
bool lld::isValidCIdentifier(StringRef s) {
  return !s.empty() && (isAlpha(s[0]) || s[0] == '_') &&
         std::all_of(s.begin() + 1, s.end(),
                     [](char c) { return c == '_' || isAlnum(c); });
}

// Write the contents of the a buffer to a file
void lld::saveBuffer(StringRef buffer, const Twine &path) {
  std::error_code ec;
  raw_fd_ostream os(path.str(), ec, sys::fs::OpenFlags::OF_None);
  if (ec)
    error("cannot create " + path + ": " + ec.message());
  os << buffer;
}