/* 7zFile.c -- File IO

 2009-11-24 : Igor Pavlov : Public domain */

 
 #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
 }
 
 
 /* ---------- 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;
 }