7zFile.cc

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/* 7zFile.c -- File IO
2009-11-24 : Igor Pavlov : Public domain */
 
#include "7zFile.h"
 
#ifndef USE_WINDOWS_FILE
 
#ifndef UNDER_CE
#include <cerrno>
#endif
 
#else
 
/*
   ReadFile and WriteFile functions in Windows have BUG:
   If you Read or Write 64MB or more (probably min_failure_size = 64MB - 32KB + 1)
   from/to Network file, it returns ERROR_NO_SYSTEM_RESOURCES
   (Insufficient system resources exist to complete the requested service).
   Probably in some version of Windows there are problems with other sizes:
   for 32 MB (maybe also for 16 MB).
   And message can be "Network connection was lost"
*/
 
#define kChunkSizeMax (1 << 22)
 
#endif
 
void File_Construct(CSzFile *p) {
#ifdef USE_WINDOWS_FILE
  p->handle = INVALID_HANDLE_VALUE;
#else
  p->file = nullptr;
#endif
}
 
#if !defined(UNDER_CE) || !defined(USE_WINDOWS_FILE)
static WRes File_Open(CSzFile *p, const char *name, int writeMode) {
#ifdef USE_WINDOWS_FILE
  p->handle = CreateFileA(name,
                          writeMode ? GENERIC_WRITE : GENERIC_READ,
                          FILE_SHARE_READ,
                          NULL,
                          writeMode ? CREATE_ALWAYS : OPEN_EXISTING,
                          FILE_ATTRIBUTE_NORMAL,
                          NULL);
  return (p->handle != INVALID_HANDLE_VALUE) ? 0 : GetLastError();
#else
  p->file = fopen(name, writeMode ? "wb+" : "rb");
  return (p->file != nullptr) ? 0 :
#ifdef UNDER_CE
                              2; /* ENOENT */
#else
                              errno;
#endif
#endif
}
 
WRes InFile_Open(CSzFile *p, const char *name) { return File_Open(p, name, 0); }
WRes OutFile_Open(CSzFile *p, const char *name) { return File_Open(p, name, 1); }
#endif
 
#ifdef USE_WINDOWS_FILE
static WRes File_OpenW(CSzFile *p, const WCHAR *name, int writeMode) {
  p->handle = CreateFileW(name,
                          writeMode ? GENERIC_WRITE : GENERIC_READ,
                          FILE_SHARE_READ,
                          NULL,
                          writeMode ? CREATE_ALWAYS : OPEN_EXISTING,
                          FILE_ATTRIBUTE_NORMAL,
                          NULL);
  return (p->handle != INVALID_HANDLE_VALUE) ? 0 : GetLastError();
}
WRes InFile_OpenW(CSzFile *p, const WCHAR *name) { return File_OpenW(p, name, 0); }
WRes OutFile_OpenW(CSzFile *p, const WCHAR *name) { return File_OpenW(p, name, 1); }
#endif
 
WRes File_Close(CSzFile *p) {
#ifdef USE_WINDOWS_FILE
  if (p->handle != INVALID_HANDLE_VALUE) {
    if (!CloseHandle(p->handle))
      return GetLastError();
    p->handle = INVALID_HANDLE_VALUE;
  }
#else
  if (p->file != nullptr) {
    int res = fclose(p->file);
    if (res != 0)
      return res;
    p->file = nullptr;
  }
#endif
  return 0;
}
 
WRes File_Read(CSzFile *p, void *data, size_t *size) {
  size_t originalSize = *size;
  if (originalSize == 0)
    return 0;
 
#ifdef USE_WINDOWS_FILE
 
  *size = 0;
  do {
    DWORD curSize = (originalSize > kChunkSizeMax) ? kChunkSizeMax : (DWORD)originalSize;
    DWORD processed = 0;
    BOOL res = ReadFile(p->handle, data, curSize, &processed, NULL);
    data = (void *)((Byte *)data + processed);
    originalSize -= processed;
    *size += processed;
    if (!res)
      return GetLastError();
    if (processed == 0)
      break;
  } while (originalSize > 0);
  return 0;
 
#else
 
  *size = fread(data, 1, originalSize, p->file);
  if (*size == originalSize)
    return 0;
  return ferror(p->file);
 
#endif
}
 
WRes File_Write(CSzFile *p, const void *data, size_t *size) {
  size_t originalSize = *size;
  if (originalSize == 0)
    return 0;
 
#ifdef USE_WINDOWS_FILE
 
  *size = 0;
  do {
    DWORD curSize = (originalSize > kChunkSizeMax) ? kChunkSizeMax : (DWORD)originalSize;
    DWORD processed = 0;
    BOOL res = WriteFile(p->handle, data, curSize, &processed, NULL);
    data = (void *)((Byte *)data + processed);
    originalSize -= processed;
    *size += processed;
    if (!res)
      return GetLastError();
    if (processed == 0)
      break;
  } while (originalSize > 0);
  return 0;
 
#else
 
  *size = fwrite(data, 1, originalSize, p->file);
  if (*size == originalSize)
    return 0;
  return ferror(p->file);
 
#endif
}
 
WRes File_Seek(CSzFile *p, Int64 *pos, ESzSeek origin) {
#ifdef USE_WINDOWS_FILE
 
  LARGE_INTEGER value;
  DWORD moveMethod;
  value.LowPart = (DWORD)*pos;
  value.HighPart = (LONG)((UInt64)*pos >> 16 >> 16); /* for case when UInt64 is 32-bit only */
  switch (origin) {
    case SZ_SEEK_SET:
      moveMethod = FILE_BEGIN;
      break;
    case SZ_SEEK_CUR:
      moveMethod = FILE_CURRENT;
      break;
    case SZ_SEEK_END:
      moveMethod = FILE_END;
      break;
    default:
      return ERROR_INVALID_PARAMETER;
  }
  value.LowPart = SetFilePointer(p->handle, value.LowPart, &value.HighPart, moveMethod);
  if (value.LowPart == 0xFFFFFFFF) {
    WRes res = GetLastError();
    if (res != NO_ERROR)
      return res;
  }
  *pos = ((Int64)value.HighPart << 32) | value.LowPart;
  return 0;
 
#else
 
  int moveMethod;
  int res;
  switch (origin) {
    case SZ_SEEK_SET:
      moveMethod = SEEK_SET;
      break;
    case SZ_SEEK_CUR:
      moveMethod = SEEK_CUR;
      break;
    case SZ_SEEK_END:
      moveMethod = SEEK_END;
      break;
    default:
      return 1;
  }
  res = fseek(p->file, (long)*pos, moveMethod);
  *pos = ftell(p->file);
  return res;
 
#endif
}
 
WRes File_GetLength(CSzFile *p, UInt64 *length) {
#ifdef USE_WINDOWS_FILE
 
  DWORD sizeHigh;
  DWORD sizeLow = GetFileSize(p->handle, &sizeHigh);
  if (sizeLow == 0xFFFFFFFF) {
    DWORD res = GetLastError();
    if (res != NO_ERROR)
      return res;
  }
  *length = (((UInt64)sizeHigh) << 32) + sizeLow;
  return 0;
 
#else
 
  long pos = ftell(p->file);
  int res = fseek(p->file, 0, SEEK_END);
  *length = ftell(p->file);
  fseek(p->file, pos, SEEK_SET);
  return res;
 
#endif
}
 
/* ---------- FileSeqInStream ---------- */
 
static SRes FileSeqInStream_Read(void *pp, void *buf, size_t *size) {
  CFileSeqInStream *p = (CFileSeqInStream *)pp;
  return File_Read(&p->file, buf, size) == 0 ? SZ_OK : SZ_ERROR_READ;
}
 
void FileSeqInStream_CreateVTable(CFileSeqInStream *p) { p->s.Read = FileSeqInStream_Read; }
 
/* ---------- FileInStream ---------- */
 
static SRes FileInStream_Read(void *pp, void *buf, size_t *size) {
  CFileInStream *p = (CFileInStream *)pp;
  return (File_Read(&p->file, buf, size) == 0) ? SZ_OK : SZ_ERROR_READ;
}
 
static SRes FileInStream_Seek(void *pp, Int64 *pos, ESzSeek origin) {
  CFileInStream *p = (CFileInStream *)pp;
  return File_Seek(&p->file, pos, origin);
}
 
void FileInStream_CreateVTable(CFileInStream *p) {
  p->s.Read = FileInStream_Read;
  p->s.Seek = FileInStream_Seek;
}
 
/* ---------- FileOutStream ---------- */
 
static size_t FileOutStream_Write(void *pp, const void *data, size_t size) {
  CFileOutStream *p = (CFileOutStream *)pp;
  File_Write(&p->file, data, &size);
  return size;
}
 
void FileOutStream_CreateVTable(CFileOutStream *p) { p->s.Write = FileOutStream_Write; }