Add documentation, archive_sys FFI

* Add doxygen documentation generator into build
* Create archive_sys low-level abstraction over libarchive

doc/meson.build

@@ -0,0 +1,34 @@
+doxygen = find_program('doxygen', required : false)
+
+if not doxygen.found()
+  error('MESON_SKIP_TEST doxygen not found.')
+endif
+
+cdata = configuration_data()
+cdata.set('VERSION', meson.project_version())
+
+if find_program('dot', required : false).found()
+  cdata.set('HAVE_DOT', 'YES')
+else
+  cdata.set('HAVE_DOT', 'NO')
+endif
+
+cdata.set('PROJECT_NAME', meson.project_name())
+cdata.set('PROJECT_SRCDIR', join_paths(meson.current_source_dir(),'..','src',meson.project_name()))
+cdata.set('PROJECT_DOCDIR', meson.current_source_dir())
+cdata.set('PROJECT_TESTDIR', join_paths(meson.current_source_dir(),'..','test'))
+
+doxyfile = configure_file(input: 'Doxyfile.in',
+                          output: 'Doxyfile',
+                          configuration: cdata,
+                          install: false)
+
+datadir = join_paths(get_option('datadir'), 'doc','xwim')
+
+html_target = custom_target('doc',
+			    build_always_stale : not meson.is_subproject(),
+                            input: doxyfile,
+                            output: 'html',
+                            command: [doxygen, doxyfile],
+                            install: not meson.is_subproject(),
+                            install_dir: datadir)

meson.build

@@ -1,2 +1,6 @@
-project('xwim', 'cpp', default_options : ['cpp_std=c++17'])
+project('xwim', 'cpp',
+        version: '0.1',
+        default_options: ['cpp_std=c++17'])
+
 subdir('src')
+subdir('doc')

src/archive.cpp

@@ -11,28 +11,17 @@ namespace logger = spdlog;
 #include <iostream>
 #include <stdexcept>
 
+#include "archive_sys.hpp"
 #include "archive.hpp"
 #include "spec.hpp"
 
 namespace xwim {
 
-static archive_entry* _archive_next_entry(archive* archive) {
-  int r;  // libarchive error handling
-  archive_entry* entry;
-  logger::trace("Listing next archive entry");
-  r = archive_read_next_header(archive, &entry);
-  if (r != ARCHIVE_OK)
-    throw(ArchiveException{"Could not list archive", archive});
-
-  logger::trace("Got archive header");
-  return entry;
-}
-
 static void _spec_is_root_filename(ArchiveSpec* spec,
-                                   archive_entry* entry,
+                                   ArchiveEntrySys& entry,
                                    std::filesystem::path* filepath) {
-  std::filesystem::path entry_path{archive_entry_pathname(entry)};
-  std::filesystem::path norm_stem = filepath->filename();
+  auto entry_path = entry.path();
+  auto norm_stem = filepath->filename();
 
   while (norm_stem.has_extension())
     norm_stem = norm_stem.stem();
@@ -48,28 +37,30 @@ static void _spec_is_root_filename(ArchiveSpec* spec,
   logger::debug("\t-> Archive stem: {}", norm_stem.string());
 }
 
-static void _spec_is_root_dir(ArchiveSpec* spec, archive_entry* entry) {
-  if (S_ISDIR(archive_entry_filetype(entry))) {
+static void _spec_is_root_dir(ArchiveSpec* spec, ArchiveEntrySys& entry) {
+  if (entry.is_directory()) {
     logger::debug("Archive root is directory");
     spec->is_root_dir = true;
   } else {
     logger::debug("Archive root is not a directory");
     spec->is_root_dir = false;
   }
-  logger::debug("\t-> Archive mode_t: {0:o}", archive_entry_filetype(entry));
+  logger::debug("\t-> Archive mode_t: {0:o}", entry.file_type());
 }
 
 static void _spec_has_single_root(ArchiveSpec* spec,
-                                  archive_entry* first_entry,
-                                  archive* archive) {
-  std::filesystem::path first_entry_root =
-      *(std::filesystem::path{archive_entry_pathname(first_entry)}.begin());
+                                  ArchiveEntrySys& first_entry,
+                                  ArchiveReaderSys& archive_reader) {
+  std::filesystem::path first_entry_root = *(first_entry.path().begin());
   logger::trace("Testing roots");
 
   spec->has_single_root = true;
-  archive_entry* entry;
-  while (archive_read_next_header(archive, &entry) == ARCHIVE_OK) {
-    std::filesystem::path next_entry{archive_entry_pathname(entry)};
+
+  while (true) {
+    ArchiveEntrySys& entry = archive_reader.next();
+    if(entry.is_empty()) break;
+
+    auto next_entry = entry.path();
     logger::trace("Path: {}, Root: {}", next_entry.string(),
                   next_entry.begin()->string());
 
@@ -83,25 +74,12 @@ static void _spec_has_single_root(ArchiveSpec* spec,
       break;
     }
   }
+
   if (spec->has_single_root)
     logger::debug("Archive has single root: {}", first_entry_root.string());
 }
 
-Archive::Archive(std::filesystem::path path) : path{path} {
-  int r;  // libarchive error handling
-
-  logger::trace("Setting up archive reader");
-  this->xwim_archive = archive_read_new();
-  archive_read_support_filter_all(this->xwim_archive);
-  archive_read_support_format_all(this->xwim_archive);
-
-  logger::trace("Reading archive at {}", path.c_str());
-  r = archive_read_open_filename(this->xwim_archive, path.c_str(), 10240);
-  if (r != ARCHIVE_OK)
-    throw ArchiveException{"Could not open archive file", this->xwim_archive};
-
-  logger::trace("Archive read succesfully");
-}
+Archive::Archive(std::filesystem::path path) : path{path} {}
 
 Archive::~Archive() {
   archive_read_free(this->xwim_archive);
@@ -110,39 +88,38 @@ Archive::~Archive() {
 ArchiveSpec Archive::check() {
   logger::trace("Creating archive spec for {}", this->path.string());
 
+  ArchiveReaderSys archive_reader {this->path};
+
   ArchiveSpec archive_spec;
 
-  archive_entry* first_entry = _archive_next_entry(this->xwim_archive);
-  if (first_entry == nullptr) {  // archive is empty
+  ArchiveEntrySys& first_entry = archive_reader.next();
+
+  if (first_entry.is_empty()) {  // archive is empty
     logger::debug("Archive is empty");
     return {false, false, false};
   }
 
-  logger::trace("Found archive entry {}", archive_entry_pathname(first_entry));
+  logger::trace("Found archive entry {}", first_entry.path_name());
 
   _spec_is_root_filename(&archive_spec, first_entry, &this->path);
   _spec_is_root_dir(&archive_spec, first_entry);
-  _spec_has_single_root(&archive_spec, first_entry, this->xwim_archive);
+  _spec_has_single_root(&archive_spec, first_entry, archive_reader);
 
   return archive_spec;
 }
 
-static void _extract_make_dir(ExtractSpec extract_spec,
-                              archive* archive) {
-  if (extract_spec.make_dir) {
-    try {
-      logger::trace("Creating directory {}", extract_spec.dirname.string());
-      std::filesystem::create_directories(extract_spec.dirname);
-    } catch (std::filesystem::filesystem_error& err) {
-      throw ArchiveException{err.what(), archive};
-    } catch (std::bad_alloc& err) {
-      throw ArchiveException{err.what(), archive};
-    }
-  }
-}
-
 void Archive::extract(ExtractSpec extract_spec) {
-  _extract_make_dir(extract_spec, this->xwim_archive);
+  ArchiveExtractorSys extractor;
+
+  if(extract_spec.make_dir) {
+    logger::trace("Creating extract directory {}", extract_spec.dirname.string());
+    extractor = ArchiveExtractorSys{extract_spec.dirname};
+  } else {
+    extractor = ArchiveExtractorSys{};
+  }
+
+  ArchiveReaderSys reader{this->path};
+  extractor.extract_all(reader);
 }
 
 }  // namespace xwim

src/archive_sys.cpp

@@ -0,0 +1,125 @@
+#include <archive_entry.h>
+#include <spdlog/spdlog.h>
+namespace logger = spdlog;
+
+#include "archive_sys.hpp"
+
+#include <archive.h>
+#include <filesystem>
+#include <memory>
+
+bool xwim::ArchiveEntrySys::is_empty() {
+  return (this->ae.get() == nullptr);
+}
+
+std::string xwim::ArchiveEntrySys::path_name() {
+  return archive_entry_pathname(this->ae.get());
+}
+
+std::filesystem::path xwim::ArchiveEntrySys::path() {
+  return std::filesystem::path{this->path_name()};
+}
+
+mode_t xwim::ArchiveEntrySys::file_type() {
+  return archive_entry_filetype(this->ae.get());
+}
+
+bool xwim::ArchiveEntrySys::is_directory() {
+  return S_ISDIR(this->file_type());
+}
+
+xwim::ArchiveReaderSys::ArchiveReaderSys(std::filesystem::path& path) {
+  int r;  // libarchive error handling
+
+  logger::trace("Setting up archive reader");
+  this->ar = archive_read_new();
+  archive_read_support_filter_all(this->ar);
+  archive_read_support_format_all(this->ar);
+
+  logger::trace("Reading archive at {}", path.c_str());
+  r = archive_read_open_filename(this->ar, path.c_str(), 10240);
+  if (r != ARCHIVE_OK)
+    throw ArchiveSysException{"Could not open archive file", this->ar};
+
+  logger::trace("Archive read succesfully");
+}
+
+xwim::ArchiveReaderSys::~ArchiveReaderSys() {
+  archive_free(this->ar);
+}
+
+xwim::ArchiveEntrySys& xwim::ArchiveReaderSys::next() {
+  int r;  // libarchive error handling
+  logger::trace("Listing next archive entry");
+  archive_entry* ae;
+  r = archive_read_next_header(this->ar, &ae);
+  if (r != ARCHIVE_OK)
+    throw(ArchiveSysException{"Could not list archive", this->ar});
+
+  this->cur_entry = xwim::ArchiveEntrySys { ae };
+
+
+  logger::trace("Got archive header");
+
+  return this->cur_entry;
+}
+
+xwim::ArchiveEntrySys& xwim::ArchiveReaderSys::cur() {
+  return this->cur_entry;
+}
+
+xwim::ArchiveExtractorSys::ArchiveExtractorSys(std::filesystem::path& root) {
+    std::filesystem::create_directories(root);
+    std::filesystem::current_path(root);
+
+    this->writer = archive_write_disk_new();
+    archive_write_disk_set_standard_lookup(this->writer);
+}
+
+xwim::ArchiveExtractorSys::ArchiveExtractorSys() {
+  this->writer = archive_write_disk_new();
+  archive_write_disk_set_standard_lookup(this->writer);
+}
+
+void xwim::ArchiveExtractorSys::extract_all(xwim::ArchiveReaderSys& reader) {
+  for(;;) {
+    ArchiveEntrySys& entry = reader.next();
+
+    if(entry.is_empty()) break;
+
+    this->extract(reader, entry);
+  }
+}
+
+static int copy_data(struct archive* ar, struct archive* aw) {
+  int r;
+  const void* buff;
+  size_t size;
+  int64_t offset;
+
+  for (;;) {
+    r = archive_read_data_block(ar, &buff, &size, &offset);
+    if (r == ARCHIVE_EOF)
+      return (ARCHIVE_OK);
+    if (r != ARCHIVE_OK) {
+      return (r);
+    }
+    r = archive_write_data_block(aw, buff, size, offset);
+    if (r != ARCHIVE_OK) {
+      return (r);
+    }
+  }
+}
+
+void xwim::ArchiveExtractorSys::extract(xwim::ArchiveReaderSys& reader, xwim::ArchiveEntrySys& entry) {
+  int r;
+  r = archive_write_header(this->writer, entry.ae.get());
+  if (r != ARCHIVE_OK) {
+    throw(ArchiveSysException("Could not extract entry", reader.ar));
+  }
+
+  r = copy_data(reader.ar, this->writer);
+  if (r != ARCHIVE_OK) {
+    throw(ArchiveSysException("Could not extract entry", reader.ar));
+  }
+}

src/archive_sys.hpp

@@ -0,0 +1,99 @@
+#pragma once
+
+#include <archive.h>
+
+#include <filesystem>
+#include <memory>
+
+namespace xwim {
+
+class ArchiveEntrySys {
+ private:
+  std::function<void (archive_entry*)> ae_deleter = [](archive_entry* ae) { archive_entry_free(ae); };
+  std::unique_ptr<archive_entry, decltype(ae_deleter)> ae;
+  friend class ArchiveExtractorSys;
+
+ public:
+  ArchiveEntrySys(std::unique_ptr<archive_entry> entry)
+    : ae{ std::unique_ptr<archive_entry, decltype(ae_deleter)>{entry.release(), ae_deleter} }
+  {}
+  ArchiveEntrySys()
+    : ae{ std::unique_ptr<archive_entry, decltype(ae_deleter)>{nullptr, ae_deleter} }
+  {}
+  ArchiveEntrySys(archive_entry* entry)
+    : ae{ std::unique_ptr<archive_entry, decltype(ae_deleter)>{entry, ae_deleter} }
+  {}
+
+  bool is_empty();
+  std::string path_name();
+  std::filesystem::path path();
+  mode_t file_type();
+  bool is_directory();
+};
+
+/** A reader for archive files
+ *
+ * Shim for `libarchive`. Iterates through
+ * entries of an archive with `next()`
+ */
+class ArchiveReaderSys {
+ private:
+  archive* ar;
+  ArchiveEntrySys cur_entry;
+  friend class ArchiveExtractorSys;
+
+ public:
+  ArchiveReaderSys(std::filesystem::path& path);
+  ~ArchiveReaderSys();
+
+  /** Returns the next archive entry
+   *
+   * @return archive_entry or nullptr if end of archive reached
+   */
+  ArchiveEntrySys& next();
+
+  /** Returns the current archive entry
+   *
+   * @return archive_entry or nullptr if current entry at end of archive
+   */
+  ArchiveEntrySys& cur();
+};
+
+/** A extractor for archive files
+ *
+ * Shim for `libarchive`.
+ */
+class ArchiveExtractorSys {
+private:
+  archive* writer;
+public:
+  ArchiveExtractorSys(std::filesystem::path& root);
+  ArchiveExtractorSys();
+
+  void extract(ArchiveReaderSys& reader, ArchiveEntrySys& entry);
+  void extract_all(ArchiveReaderSys& reader);
+
+  void extract_header(ArchiveEntrySys& entry);
+  void extract_data();
+};
+
+class ArchiveSysException : public std::exception {
+ private:
+  std::string _what;
+
+ public:
+  ArchiveSysException(std::string what, archive* archive) {
+    if (archive_error_string(archive)) {
+      _what = fmt::format("{}: {}", what, archive_error_string(archive));
+    } else {
+      _what = fmt::format("{}", what);
+    }
+  }
+  ArchiveSysException(std::string what) {
+      _what = fmt::format("{}", what);
+  }
+
+  virtual const char* what() const noexcept { return this->_what.c_str(); }
+};
+
+}  // namespace xwim

src/meson.build

@@ -1,6 +1,9 @@
-src = ['main.cpp', 'archive.cpp']
+src = ['main.cpp',
+       'archive.cpp',
+       'archive_sys.cpp']
 inc = ['archive.hpp',
-       'spec.hpp']
+       'spec.hpp',
+       'archive_sys.hpp']
 
 libs = [dependency('libarchive', required: true),
         dependency('fmt', required: true),