I was in need of finding out what files were taking the most space on my hard disk so I wrote the following program to do it and I though I share it here in case others find it useful.
The code is pure STL C++ so it will also run on Mac and Linux if you want.
#include <chrono>
#include <filesystem>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <sstream>
// Create alias for std::filesystem
namespace fs = std::filesystem;
// Define the container used to store the stats. Extension, Size, Count
typedef std::map< std::string, std::pair< std::size_t, std::size_t > > StatsMap;
// Enum to make the code easier to read
enum Sizes : std::size_t {KiloByte = 0x3e8, MegaByte = 0xf4240, GigaByte = 0x3b9aca00 };
// Helper method to print a formatted size
std::string printSize(const std::size_t& size) {
std::stringstream ss;
if (size >= GigaByte) {
ss << (size / GigaByte) << 'G';
} else if (size >= MegaByte) {
ss << (size / MegaByte) << 'M';
} else if (size >= KiloByte) {
ss << size / KiloByte << 'K';
} else { ss << size << 'B';}
return ss.str();
}
// Method used to populate the map with the file stats
StatsMap getStats(const fs::path& path) {
StatsMap map;
try {
for (const auto& entry : fs::recursive_directory_iterator(path)) {
const fs::path p{ entry.path() };
const fs::file_status status{ fs::status(p) };
// If it's a dir ignore it and move on
if (fs::is_directory(status)) { continue; }
// If there's no file extension, ignore and move on
if (!p.extension().string().length()) { continue; }
// Get the information on the file
auto&[size_acc, count] = map[p.extension().string()];
// Add this files size to the entry for its extension
size_acc += fs::file_size(p);
// Increment the count of files the extension
count++;
}
} catch (fs::filesystem_error const fe) {
std::cout << "Oops! " << fe.what() << " in " << __func__ << std::endl;
}
return map;
}
// Main point of execution
int main(int argc, char ** argv) {
// See if there's a path on the command line, using . as a default
fs::path dir{ argc > 1 ? argv[1] : "." };
// Check the location actually exists
if (!fs::exists(dir)) {
std::cout << "Path at " << dir << "doesn't exist!" << std::endl;
} else {
try {
// Start the timer to see how long the operation takes
std::chrono::system_clock::time_point started{ std::chrono::system_clock::now() };
// Tell the user we're busy as it may take some time
std::cout << "Busy..." << std::endl;
// Fill the map with file stats
StatsMap map = getStats(dir);
// Iterate the map and print the information on the console.
for (const auto&[ext, stats] : map) {
const auto&[acc_size, count] = stats;
std::cout << std::setw(20) << std::left << ext << ": " << std::setw(7) << std::right << count << " files, size " << std::setw(7) << printSize(acc_size) << " avg " << printSize(acc_size / count) << " per file" << std::endl;
};
// Job done, how long did it take
std::chrono::milliseconds ms{ std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now() - started) };
std::cout << " Processing took " << ms.count() << "s with " << map.size() << " distinct extensions" << std::endl;
}
catch (std::exception const& e) {
std::cout << "Ouch " << e.what() << " in " << __func__ << std::endl;
}
}
}
Should you want to build this for yourself you first need to compile it using the command line:
cl /GA /Gz /EHsc /MD /favor:INTEL64 /Os /std:c++17 FileSizer.cpp
Once it’s compiled you need to link it to make an .exe from the .obj file produced above:
link /OUT:FileSizer.exe /MACHINE:X64 /SUBSYSTEM:CONSOLE FileSizer.obj
If you don’t have Visual Studio installed you can get it for free here:
Visual Studio Community Edition (Free)
or you can just install the free Microsoft SDK Toolchain from here:
Windows 10 SDK Toolchain
Once built its ready to run. Using a Windows Command prompt you can enter:
FileSizer
to process the current directory or you can provide a specific path on the command line, for example:
FileSizer ./MyStuff
When complete the output will be something like this:
…
.win32 : 1 files, size 887B avg 887B per file
.xaml : 2 files, size 2K avg 1K per file
.xdc : 4 files, size 37K avg 9K per file
.xlsm : 2 files, size 26K avg 13K per file
.xlsx : 2 files, size 15M avg 7M per file
.xml : 33 files, size 42K avg 1K per file
.xsd : 56 files, size 1M avg 22K per file
.y : 1 files, size 8K avg 8K per file
.yml : 11 files, size 37K avg 3K per file
.zip : 75 files, size 36M avg 491K per file
Processing took 7852s with 242 distinct extensions
Caveat:
The code will fail if it encounters an error such as Access Denied so it’s not recommended to run this from the root of C I'd suggest the best place to run from would be your home directory.
