libzip example to create archive

ziptest.cc

// Copyright (c) 2018, Chris Lalancette
//
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// modification, are permitted provided that the following conditions are met:
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//      notice, this list of conditions and the following disclaimer.
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//    * Redistributions in binary form must reproduce the above copyright
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//      this software without specific prior written permission.
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// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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#include <iostream>
#include <string>

#include <dirent.h>
#include <sys/stat.h>
#include <errno.h>
#include <string.h>

#include <zip.h>

static bool is_dir(const std::string& dir)
{
  struct stat st;
  ::stat(dir.c_str(), &st);
  return S_ISDIR(st.st_mode);
}

static void walk_directory(const std::string& startdir, const std::string& inputdir, zip_t *zipper)
{
  DIR *dp = ::opendir(inputdir.c_str());
  if (dp == nullptr) {
    throw std::runtime_error("Failed to open input directory: " + std::string(::strerror(errno)));
  }

  struct dirent *dirp;
  while ((dirp = readdir(dp)) != NULL) {
    if (dirp->d_name != std::string(".") && dirp->d_name != std::string("..")) {
      std::string fullname = inputdir + "/" + dirp->d_name;
      if (is_dir(fullname)) {
        if (zip_dir_add(zipper, fullname.substr(startdir.length() + 1).c_str(), ZIP_FL_ENC_UTF_8) < 0) {
          throw std::runtime_error("Failed to add directory to zip: " + std::string(zip_strerror(zipper)));
        }
        walk_directory(startdir, fullname, zipper);
      } else {
        zip_source_t *source = zip_source_file(zipper, fullname.c_str(), 0, 0);
        if (source == nullptr) {
          throw std::runtime_error("Failed to add file to zip: " + std::string(zip_strerror(zipper)));
        }
        if (zip_file_add(zipper, fullname.substr(startdir.length() + 1).c_str(), source, ZIP_FL_ENC_UTF_8) < 0) {
          zip_source_free(source);
          throw std::runtime_error("Failed to add file to zip: " + std::string(zip_strerror(zipper)));
        }
      }
    }
  }
  ::closedir(dp);
}

static void zip_directory(const std::string& inputdir, const std::string& output_filename)
{
  int errorp;
  zip_t *zipper = zip_open(output_filename.c_str(), ZIP_CREATE | ZIP_EXCL, &errorp);
  if (zipper == nullptr) {
    zip_error_t ziperror;
    zip_error_init_with_code(&ziperror, errorp);
    throw std::runtime_error("Failed to open output file " + output_filename + ": " + zip_error_strerror(&ziperror));
  }

  try {
    walk_directory(inputdir, inputdir, zipper);
  } catch(...) {
    zip_close(zipper);
    throw;
  }

  zip_close(zipper);
}

int main(int argc, char *argv[])
{
  if (argc != 3) {
    fprintf(stderr, "Usage: %s <input_dir> <output_file>\n", argv[0]);
    return 1;
  }
  zip_directory(argv[1], argv[2]);

  return 0;
}

Why isn't something like this in the official docs? Or at least on the codes github source page...
Thanks! I will be using but this is a good start!

Great example! I was also wodering why this isn't part of the official docs, the examples there are just so bad.

You are, a pure hero! You saved my ass big time. Couldn't figure out a way to do it recursively and placeall files in their respective directories. your solution with the substraction of the string is just briljant! My man (or woman)!

Bad example, why not using std::filesystem? This directory walking looks ugly

Thanks for the example!

@clalancette Can you please provide a license for your code that I can use? I would like to give you credit for this major help. Thanks!

@clalancette Can you please provide a license for your code that I can use? I would like to give you credit for this major help. Thanks!

I went ahead and added a BSD license header to the code. Thanks for asking before using it!

For MacOS apps with App Sandbox, you need the write permission for the destination folder not just the destination file. It failed silently on MacOS Ventura when I only had the file permission without the folder permission.

thanks for these snippets