gecko-dev/xpcom/io/nsLocalFileCommon.cpp

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsIServiceManager.h"

#include "nsLocalFile.h" // includes platform-specific headers

#include "nsString.h"
#include "nsCOMPtr.h"
#include "nsReadableUtils.h"
#include "nsPrintfCString.h"
#include "nsCRT.h"
#include "nsNativeCharsetUtils.h"
#include "nsUTF8Utils.h"

#ifdef XP_WIN
#include <string.h>
#endif


void NS_StartupLocalFile()
{
  nsLocalFile::GlobalInit();
}

void NS_ShutdownLocalFile()
{
  nsLocalFile::GlobalShutdown();
}

#if !defined(MOZ_WIDGET_COCOA) && !defined(XP_WIN)
NS_IMETHODIMP
nsLocalFile::InitWithFile(nsIFile *aFile)
{
  if (NS_WARN_IF(!aFile))
    return NS_ERROR_INVALID_ARG;

  nsAutoCString path;
  aFile->GetNativePath(path);
  if (path.IsEmpty())
    return NS_ERROR_INVALID_ARG;
  return InitWithNativePath(path);
}
#endif

#define kMaxFilenameLength 255
#define kMaxExtensionLength 100
#define kMaxSequenceNumberLength 5 // "-9999"
// requirement: kMaxExtensionLength < kMaxFilenameLength - kMaxSequenceNumberLength

NS_IMETHODIMP
nsLocalFile::CreateUnique(uint32_t type, uint32_t attributes)
{
  nsresult rv;
  bool longName;

#ifdef XP_WIN
  nsAutoString pathName, leafName, rootName, suffix;
  rv = GetPath(pathName);
#else
  nsAutoCString pathName, leafName, rootName, suffix;
  rv = GetNativePath(pathName);
#endif
  if (NS_FAILED(rv))
    return rv;

  longName = (pathName.Length() + kMaxSequenceNumberLength >
              kMaxFilenameLength);
  if (!longName)
  {
    rv = Create(type, attributes);
    if (rv != NS_ERROR_FILE_ALREADY_EXISTS)
      return rv;
  }

#ifdef XP_WIN
  rv = GetLeafName(leafName);
  if (NS_FAILED(rv))
    return rv;

  const int32_t lastDot = leafName.RFindChar(char16_t('.'));
#else
  rv = GetNativeLeafName(leafName);
  if (NS_FAILED(rv))
    return rv;

  const int32_t lastDot = leafName.RFindChar('.');
#endif

  if (lastDot == kNotFound)
  {
    rootName = leafName;
  }
  else
  {
    suffix = Substring(leafName, lastDot);      // include '.'
    rootName = Substring(leafName, 0, lastDot); // strip suffix and dot
  }

  if (longName)
  {
    int32_t maxRootLength = (kMaxFilenameLength -
                             (pathName.Length() - leafName.Length()) -
                             suffix.Length() - kMaxSequenceNumberLength);

    // We cannot create an item inside a directory whose name is too long.
    // Also, ensure that at least one character remains after we truncate
    // the root name, as we don't want to end up with an empty leaf name.
    if (maxRootLength < 2)
      return NS_ERROR_FILE_UNRECOGNIZED_PATH;

#ifdef XP_WIN
    // ensure that we don't cut the name in mid-UTF16-character
    rootName.SetLength(NS_IS_LOW_SURROGATE(rootName[maxRootLength]) ?
                       maxRootLength - 1 : maxRootLength);
    SetLeafName(rootName + suffix);
#else
    if (NS_IsNativeUTF8())
    {
      // ensure that we don't cut the name in mid-UTF8-character
      // (assume the name is valid UTF8 to begin with)
      while (UTF8traits::isInSeq(rootName[maxRootLength]))
        --maxRootLength;

      // Another check to avoid ending up with an empty leaf name.
      if (maxRootLength == 0 && suffix.IsEmpty())
        return NS_ERROR_FILE_UNRECOGNIZED_PATH;
    }

    rootName.SetLength(maxRootLength);
    SetNativeLeafName(rootName + suffix);
#endif
    nsresult rv = Create(type, attributes);
    if (rv != NS_ERROR_FILE_ALREADY_EXISTS)
      return rv;
  }

  for (int indx = 1; indx < 10000; indx++)
  {
    // start with "Picture-1.jpg" after "Picture.jpg" exists
#ifdef XP_WIN
    SetLeafName(rootName +
                NS_ConvertASCIItoUTF16(nsPrintfCString("-%d", indx)) +
                suffix);
#else
    SetNativeLeafName(rootName + nsPrintfCString("-%d", indx) + suffix);
#endif
    rv = Create(type, attributes);
    if (NS_SUCCEEDED(rv) || rv != NS_ERROR_FILE_ALREADY_EXISTS)
      return rv;
  }

  // The disk is full, sort of
  return NS_ERROR_FILE_TOO_BIG;
}

#if defined(XP_WIN)
static const char16_t kPathSeparatorChar       = '\\';
#elif defined(XP_UNIX)
static const char16_t kPathSeparatorChar       = '/';
#else
#error Need to define file path separator for your platform
#endif

static int32_t SplitPath(char16_t *path, char16_t **nodeArray, int32_t arrayLen)
{
  if (*path == 0)
    return 0;

  char16_t **nodePtr = nodeArray;
  if (*path == kPathSeparatorChar)
    path++;
  *nodePtr++ = path;

  for (char16_t *cp = path; *cp != 0; cp++) {
    if (*cp == kPathSeparatorChar) {
      *cp++ = 0;
      if (*cp == 0)
        break;
      if (nodePtr - nodeArray >= arrayLen)
        return -1;
      *nodePtr++ = cp;
    }
  }
  return nodePtr - nodeArray;
}


NS_IMETHODIMP
nsLocalFile::GetRelativeDescriptor(nsIFile *fromFile, nsACString& _retval)
{
  if (NS_WARN_IF(!fromFile))
    return NS_ERROR_INVALID_ARG;
  const int32_t kMaxNodesInPath = 32;

  //
  // _retval will be UTF-8 encoded
  //

  nsresult rv;
  _retval.Truncate(0);

  nsAutoString thisPath, fromPath;
  char16_t *thisNodes[kMaxNodesInPath], *fromNodes[kMaxNodesInPath];
  int32_t  thisNodeCnt, fromNodeCnt, nodeIndex;

  rv = GetPath(thisPath);
  if (NS_FAILED(rv))
    return rv;
  rv = fromFile->GetPath(fromPath);
  if (NS_FAILED(rv))
    return rv;

  // get raw pointer to mutable string buffer
  char16_t *thisPathPtr; thisPath.BeginWriting(thisPathPtr);
  char16_t *fromPathPtr; fromPath.BeginWriting(fromPathPtr);

  thisNodeCnt = SplitPath(thisPathPtr, thisNodes, kMaxNodesInPath);
  fromNodeCnt = SplitPath(fromPathPtr, fromNodes, kMaxNodesInPath);
  if (thisNodeCnt < 0 || fromNodeCnt < 0)
    return NS_ERROR_FAILURE;

  for (nodeIndex = 0; nodeIndex < thisNodeCnt && nodeIndex < fromNodeCnt; ++nodeIndex) {
#ifdef XP_WIN
    if (_wcsicmp(char16ptr_t(thisNodes[nodeIndex]), char16ptr_t(fromNodes[nodeIndex])))
      break;
#else
    if (nsCRT::strcmp(thisNodes[nodeIndex], fromNodes[nodeIndex]))
      break;
#endif
  }

  int32_t branchIndex = nodeIndex;
  for (nodeIndex = branchIndex; nodeIndex < fromNodeCnt; nodeIndex++)
    _retval.AppendLiteral("../");
  for (nodeIndex = branchIndex; nodeIndex < thisNodeCnt; nodeIndex++) {
    NS_ConvertUTF16toUTF8 nodeStr(thisNodes[nodeIndex]);
    _retval.Append(nodeStr);
    if (nodeIndex + 1 < thisNodeCnt)
      _retval.Append('/');
  }

  return NS_OK;
}

NS_IMETHODIMP
nsLocalFile::SetRelativeDescriptor(nsIFile *fromFile, const nsACString& relativeDesc)
{
  NS_NAMED_LITERAL_CSTRING(kParentDirStr, "../");

  nsCOMPtr<nsIFile> targetFile;
  nsresult rv = fromFile->Clone(getter_AddRefs(targetFile));
  if (NS_FAILED(rv))
    return rv;

  //
  // relativeDesc is UTF-8 encoded
  //

  nsCString::const_iterator strBegin, strEnd;
  relativeDesc.BeginReading(strBegin);
  relativeDesc.EndReading(strEnd);

  nsCString::const_iterator nodeBegin(strBegin), nodeEnd(strEnd);
  nsCString::const_iterator pos(strBegin);

  nsCOMPtr<nsIFile> parentDir;
  while (FindInReadable(kParentDirStr, nodeBegin, nodeEnd)) {
    rv = targetFile->GetParent(getter_AddRefs(parentDir));
    if (NS_FAILED(rv))
      return rv;
    if (!parentDir)
      return NS_ERROR_FILE_UNRECOGNIZED_PATH;
    targetFile = parentDir;

    nodeBegin = nodeEnd;
    pos = nodeEnd;
    nodeEnd = strEnd;
  }

  nodeBegin = nodeEnd = pos;
  while (nodeEnd != strEnd) {
    FindCharInReadable('/', nodeEnd, strEnd);
    targetFile->Append(NS_ConvertUTF8toUTF16(Substring(nodeBegin, nodeEnd)));
    if (nodeEnd != strEnd) // If there's more left in the string, inc over the '/' nodeEnd is on.
      ++nodeEnd;
    nodeBegin = nodeEnd;
  }

  return InitWithFile(targetFile);
}