Add error code to zip::exception.

src/main.cpp

@@ -18,6 +18,7 @@
 #include "fs-compat.hpp"
 #include "options.hpp"
 #include "search.hpp"
+#include "zip.hpp"
 
 #include <boost/locale/generator.hpp>
 #include <boost/locale/message.hpp>
@@ -145,7 +146,7 @@ int main(int argc, char *argv[])
                     std::lock_guard<std::mutex> guard(mutex_matches_all);
                     matches_all.emplace_back(matches);
                 }
-                catch (const std::exception &e)
+                catch (const zip::exception &e)
                 {
                     cerr << translate("ERROR: ") << e.what() << '\n';
                     cerr << format(translate("Error while searching {0:s}.")

src/zip.cpp

@@ -26,6 +26,8 @@
 
 #include <cstdlib>
 #include <cstring>
+#include <fstream>
+#include <stdexcept>
 #include <string>
 #include <vector>
 
@@ -92,6 +94,18 @@ std::string read_file(const fs::path &filepath, std::string_view entry_path)
 
 struct archive *open_file(const fs::path &filepath)
 {
+    std::ifstream file{filepath};
+    if (!file.good())
+    {
+        exception e{format(translate("Could not open {0:s}: "
+                                     "Permission denied.")
+                               .str(),
+                           filepath.string())};
+        e.code = 2;
+        throw exception{e};
+    }
+    file.close();
+
     auto *zipfile{archive_read_new()};
     archive_read_support_filter_all(zipfile);
     archive_read_support_format_zip(zipfile);
@@ -101,8 +115,10 @@ struct archive *open_file(const fs::path &filepath)
     {
         close_file(zipfile, filepath);
 
-        throw exception{format(translate("Could not open {0:s}.").str(),
+        exception e{format(translate("Could not open {0:s}.").str(),
                            filepath.string())};
+        e.code = 1;
+        throw exception{e};
     }
 
     return zipfile;

src/zip.hpp

@@ -21,6 +21,7 @@
 
 #include <archive.h>
 
+#include <cstdint>
 #include <stdexcept>
 #include <string>
 #include <string_view>
@@ -47,6 +48,8 @@ class exception : public std::runtime_error
 {
 public:
     using std::runtime_error::runtime_error;
+
+    std::uint8_t code{0};
 };
 
 } // namespace epubgrep::zip