/* 7zFile.c -- File IO

2017-04-03 : Igor Pavlov : Public domain */

#include "Precomp.h"

#include "7zFile.h"

#ifndef USE_WINDOWS_FILE

#ifndef UNDER_CE

#include <errno.h>

#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 = NULL;

  #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 != 0) ? 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 != NULL)

  {

    int res = fclose(p->file);

    if (res != 0)

      return res;

    p->file = NULL;

  }

  #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(const ISeqInStream *pp, void *buf, size_t *size)

{

  CFileSeqInStream *p = CONTAINER_FROM_VTBL(pp, CFileSeqInStream, vt);

  return File_Read(&p->file, buf, size) == 0 ? SZ_OK : SZ_ERROR_READ;

}

void FileSeqInStream_CreateVTable(CFileSeqInStream *p)

{

  p->vt.Read = FileSeqInStream_Read;

}

/* ---------- FileInStream ---------- */

static SRes FileInStream_Read(const ISeekInStream *pp, void *buf, size_t *size)

{

  CFileInStream *p = CONTAINER_FROM_VTBL(pp, CFileInStream, vt);

  return (File_Read(&p->file, buf, size) == 0) ? SZ_OK : SZ_ERROR_READ;

}

static SRes FileInStream_Seek(const ISeekInStream *pp, Int64 *pos, ESzSeek origin)

{

  CFileInStream *p = CONTAINER_FROM_VTBL(pp, CFileInStream, vt);

  return File_Seek(&p->file, pos, origin);

}

void FileInStream_CreateVTable(CFileInStream *p)

{

  p->vt.Read = FileInStream_Read;

  p->vt.Seek = FileInStream_Seek;

}

/* ---------- FileOutStream ---------- */

static size_t FileOutStream_Write(const ISeqOutStream *pp, const void *data, size_t size)

{

  CFileOutStream *p = CONTAINER_FROM_VTBL(pp, CFileOutStream, vt);

  File_Write(&p->file, data, &size);

  return size;

}

void FileOutStream_CreateVTable(CFileOutStream *p)

{

  p->vt.Write = FileOutStream_Write;

}