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#include <qpdf/Pl_Flate.hh>
#include <qpdf/Pl_StdioFile.hh>
#include <qpdf/Pl_Count.hh>
#include <iostream>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
FILE* safe_fopen(char const* filename, char const* mode)
{
FILE* result = fopen(filename, mode);
if (result == 0)
{
std::cerr << "fopen " << filename << " failed: " << strerror(errno)
<< std::endl;
exit(2);
}
return result;
}
void run(char const* filename)
{
std::string n1 = std::string(filename) + ".1";
std::string n2 = std::string(filename) + ".2";
std::string n3 = std::string(filename) + ".3";
FILE* o1 = safe_fopen(n1.c_str(), "wb");
FILE* o2 = safe_fopen(n2.c_str(), "wb");
FILE* o3 = safe_fopen(n3.c_str(), "wb");
Pipeline* out1 = new Pl_StdioFile("o1", o1);
Pipeline* out2 = new Pl_StdioFile("o2", o2);
Pipeline* out3 = new Pl_StdioFile("o3", o3);
// Compress the file
Pipeline* def1 = new Pl_Flate("def1", out1, Pl_Flate::a_deflate);
// Decompress the file
Pipeline* inf2 = new Pl_Flate("inf2", out2, Pl_Flate::a_inflate);
// Count bytes written to o3
Pl_Count* count3 = new Pl_Count("count3", out3);
// Do both simultaneously
Pipeline* inf3 = new Pl_Flate("inf3", count3, Pl_Flate::a_inflate);
Pipeline* def3 = new Pl_Flate("def3", inf3, Pl_Flate::a_deflate);
FILE* in1 = safe_fopen(filename, "rb");
unsigned char buf[1024];
size_t len;
while ((len = fread(buf, 1, sizeof(buf), in1)) > 0)
{
// Write to the compression pipeline
def1->write(buf, len);
// Write to the both pipeline
def3->write(buf, len);
}
def1->finish();
delete def1;
delete out1;
fclose(o1);
def3->finish();
std::cout << "bytes written to o3: " << count3->getCount() << std::endl;
delete def3;
delete inf3;
delete count3;
delete out3;
fclose(o3);
// Now read the compressed data and write to the output uncompress pipeline
FILE* in2 = safe_fopen(n1.c_str(), "rb");
while ((len = fread(buf, 1, sizeof(buf), in2)) > 0)
{
inf2->write(buf, len);
}
inf2->finish();
delete inf2;
delete out2;
fclose(o2);
// At this point, filename, filename.2, and filename.3 should have
// identical contents. filename.1 should be a compressed version.
std::cout << "done" << std::endl;
}
int main(int argc, char* argv[])
{
if (argc != 2)
{
std::cerr << "Usage: pipeline filename" << std::endl;
exit(2);
}
char* filename = argv[1];
try
{
run(filename);
}
catch (std::exception& e)
{
std::cout << e.what() << std::endl;
}
return 0;
}
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