Tesseract  3.02
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tesseract::CachedFile Class Reference

#include <cached_file.h>

List of all members.

Public Member Functions

 CachedFile (string file_name)
 ~CachedFile ()
int Read (void *read_buff, int bytes)
long Size ()
long Tell ()
bool eof ()

Detailed Description

Definition at line 33 of file cached_file.h.


Constructor & Destructor Documentation

tesseract::CachedFile::CachedFile ( string  file_name)
explicit

Definition at line 27 of file cached_file.cpp.

{
file_name_ = file_name;
buff_ = NULL;
buff_pos_ = 0;
buff_size_ = 0;
file_pos_ = 0;
file_size_ = 0;
fp_ = NULL;
}
tesseract::CachedFile::~CachedFile ( )

Definition at line 37 of file cached_file.cpp.

{
if (fp_ != NULL) {
fclose(fp_);
fp_ = NULL;
}
if (buff_ != NULL) {
delete []buff_;
buff_ = NULL;
}
}

Member Function Documentation

bool tesseract::CachedFile::eof ( )

Definition at line 142 of file cached_file.cpp.

{
if (fp_ == NULL && Open() == false) {
return true;
}
return (file_pos_ - buff_size_ + buff_pos_) >= file_size_;
}
int tesseract::CachedFile::Read ( void *  read_buff,
int  bytes 
)

Definition at line 82 of file cached_file.cpp.

{
int read_bytes = 0;
unsigned char *buff = (unsigned char *)read_buff;
// do we need to read beyond the buffer
if ((buff_pos_ + bytes) > buff_size_) {
// copy as much bytes from the current buffer if any
int copy_bytes = buff_size_ - buff_pos_;
if (copy_bytes > 0) {
memcpy(buff, buff_ + buff_pos_, copy_bytes);
buff += copy_bytes;
bytes -= copy_bytes;
read_bytes += copy_bytes;
}
// determine how much to read
buff_size_ = kCacheSize;
if ((file_pos_ + buff_size_) > file_size_) {
buff_size_ = static_cast<int>(file_size_ - file_pos_);
}
// EOF ?
if (buff_size_ <= 0 || bytes > buff_size_) {
return read_bytes;
}
// read the first chunck
if (fread(buff_, 1, buff_size_, fp_) != buff_size_) {
return read_bytes;
}
buff_pos_ = 0;
file_pos_ += buff_size_;
}
memcpy(buff, buff_ + buff_pos_, bytes);
read_bytes += bytes;
buff_pos_ += bytes;
return read_bytes;
}
long tesseract::CachedFile::Size ( )

Definition at line 126 of file cached_file.cpp.

{
if (fp_ == NULL && Open() == false) {
return 0;
}
return file_size_;
}
long tesseract::CachedFile::Tell ( )

Definition at line 134 of file cached_file.cpp.

{
if (fp_ == NULL && Open() == false) {
return 0;
}
return file_pos_ - buff_size_ + buff_pos_;
}

The documentation for this class was generated from the following files: