// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

#include "platform/globals.h"
#if defined(TARGET_OS_FUCHSIA)

#include "bin/directory.h"

#include <errno.h>  // NOLINT
#include <stdlib.h>  // NOLINT
#include <string.h>  // NOLINT
#include <sys/stat.h>  // NOLINT
#include <unistd.h>  // NOLINT

#include "bin/dartutils.h"
#include "bin/file.h"
#include "bin/platform.h"
#include "platform/signal_blocker.h"

namespace dart {
namespace bin {

PathBuffer::PathBuffer() : length_(0) {
  data_ = calloc(PATH_MAX + 1, sizeof(char));  // NOLINT
}


PathBuffer::~PathBuffer() {
  free(data_);
}


bool PathBuffer::AddW(const wchar_t* name) {
  UNREACHABLE();
  return false;
}


char* PathBuffer::AsString() const {
  return reinterpret_cast<char*>(data_);
}


wchar_t* PathBuffer::AsStringW() const {
  UNREACHABLE();
  return NULL;
}


const char* PathBuffer::AsScopedString() const {
  return DartUtils::ScopedCopyCString(AsString());
}


bool PathBuffer::Add(const char* name) {
  const intptr_t name_length = strnlen(name, PATH_MAX + 1);
  if (name_length == 0) {
    errno = EINVAL;
    return false;
  }
  char* data = AsString();
  int written = snprintf(data + length_,
                         PATH_MAX - length_,
                         "%s",
                         name);
  data[PATH_MAX] = '\0';
  if ((written <= (PATH_MAX - length_)) &&
      (written > 0) &&
      (static_cast<size_t>(written) == strnlen(name, PATH_MAX + 1))) {
    length_ += written;
    return true;
  } else {
    errno = ENAMETOOLONG;
    return false;
  }
}


void PathBuffer::Reset(intptr_t new_length) {
  length_ = new_length;
  AsString()[length_] = '\0';
}


ListType DirectoryListingEntry::Next(DirectoryListing* listing) {
  UNIMPLEMENTED();
  return kListError;
}


DirectoryListingEntry::~DirectoryListingEntry() {
  UNIMPLEMENTED();
}


void DirectoryListingEntry::ResetLink() {
  UNIMPLEMENTED();
}


Directory::ExistsResult Directory::Exists(const char* dir_name) {
  struct stat entry_info;
  int success = NO_RETRY_EXPECTED(stat(dir_name, &entry_info));
  if (success == 0) {
    if (S_ISDIR(entry_info.st_mode)) {
      return EXISTS;
    } else {
      return DOES_NOT_EXIST;
    }
  } else {
    if ((errno == EACCES) ||
        (errno == EBADF) ||
        (errno == EFAULT) ||
        (errno == ENOMEM) ||
        (errno == EOVERFLOW)) {
      // Search permissions denied for one of the directories in the
      // path or a low level error occured. We do not know if the
      // directory exists.
      return UNKNOWN;
    }
    ASSERT((errno == ELOOP) ||
           (errno == ENAMETOOLONG) ||
           (errno == ENOENT) ||
           (errno == ENOTDIR));
    return DOES_NOT_EXIST;
  }
}


char* Directory::CurrentNoScope() {
  return getcwd(NULL, 0);
}


const char* Directory::Current() {
  char buffer[PATH_MAX];
  if (getcwd(buffer, PATH_MAX) == NULL) {
    return NULL;
  }
  return DartUtils::ScopedCopyCString(buffer);
}


bool Directory::SetCurrent(const char* path) {
  return (NO_RETRY_EXPECTED(chdir(path)) == 0);
}


bool Directory::Create(const char* dir_name) {
  // Create the directory with the permissions specified by the
  // process umask.
  int result = NO_RETRY_EXPECTED(mkdir(dir_name, 0777));
  // If the directory already exists, treat it as a success.
  if ((result == -1) && (errno == EEXIST)) {
    return (Exists(dir_name) == EXISTS);
  }
  return (result == 0);
}


const char* Directory::SystemTemp() {
  PathBuffer path;
  const char* temp_dir = getenv("TMPDIR");
  if (temp_dir == NULL) {
    temp_dir = getenv("TMP");
  }
  if (temp_dir == NULL) {
    temp_dir = "/tmp";
  }
  if (!path.Add(temp_dir)) {
    return NULL;
  }

  // Remove any trailing slash.
  char* result = path.AsString();
  int length = strlen(result);
  if ((length > 1) && (result[length - 1] == '/')) {
    result[length - 1] = '\0';
  }
  return path.AsScopedString();
}


const char* Directory::CreateTemp(const char* prefix) {
  // Returns a new, unused directory name, adding characters to the end
  // of prefix.  Creates the directory with the permissions specified
  // by the process umask.
  // The return value is Dart_ScopeAllocated.
  PathBuffer path;
  if (!path.Add(prefix)) {
    return NULL;
  }
  if (!path.Add("XXXXXX")) {
    // Pattern has overflowed.
    return NULL;
  }
  char* result;
  do {
    result = mkdtemp(path.AsString());
  } while ((result == NULL) && (errno == EINTR));
  if (result == NULL) {
    return NULL;
  }
  return path.AsScopedString();
}


bool Directory::Delete(const char* dir_name, bool recursive) {
  if (!recursive) {
    if ((File::GetType(dir_name, false) == File::kIsLink) &&
        (File::GetType(dir_name, true) == File::kIsDirectory)) {
      return NO_RETRY_EXPECTED(unlink(dir_name)) == 0;
    }
    return NO_RETRY_EXPECTED(rmdir(dir_name)) == 0;
  } else {
    UNIMPLEMENTED();
    return false;
  }
}


bool Directory::Rename(const char* path, const char* new_path) {
  ExistsResult exists = Exists(path);
  if (exists != EXISTS) {
    return false;
  }
  return (NO_RETRY_EXPECTED(rename(path, new_path)) == 0);
}

}  // namespace bin
}  // namespace dart

#endif  // defined(TARGET_OS_LINUX)