Bug 27232 - fedabipkgdiff fails on gawk from Fedora 33

When running fedabipkgdiff on the gawk-5.1.0-2.fc33.aarch64.rpm
package we get this error message:

    Error encountered while running fedabipkgdiff with error message:

That is not a very useful error message to say the least.

The issue is that abipkgdiff returns with an "unknown error" which is
due to the fact that the gawk package contains a directory that is
owned by root.  As abipkgdiff tries to write temporary files into that
directory, it fails to do so.

The patch now writes the temporary ABIXML file into a sub-directory
that is not owned the package where we should have write privileges.

It also improves error reporting.

	* tools/abipkgdiff.cc (options::pkg{1,2}): Add new data members to
	store the packages to compare and have them available for the
	various functions that may need them down the road.
	(package::create_abi_file_path): Add new function.
	(compare_to_self): Use the new package::create_abi_file_path to
	create the path to the ABI file in a directory not owned by the
	package.  That should increase our chances of having the rights to
	write that one.  Make sure to emit error message when the
	comparison against self fails.
	({compare_task, self_compare_task}::perform): During the process
	of comparison if an internal error happens, report it.  Cleanup
	the existing reporting a little bit.
	(pkg_extraction_task::perform): Fix comment.
	* tests/data/test-diff-pkg/libxfce4ui-devel-4.12.1-8.fc27.ppc64-self-report-0.txt:
	Adjust.

Signed-off-by: Dodji Seketeli <dodji@redhat.com>

tests/data/test-diff-pkg/libxfce4ui-devel-4.12.1-8.fc27.ppc64-self-report-0.txt

@@ -1,4 +1,4 @@
 abipkgdiff: Could not find alternate debug info file: ../../../../.dwz/libxfce4ui-4.12.1-8.fc27.ppc64
-==== Error happened during processing of libxfce4uiglade.so: ====
+==== Error happened during processing of 'libxfce4uiglade.so' ====
 could not find alternate debug info
-==== End of error for libxfce4uiglade.so ====
+==== End of error for 'libxfce4uiglade.so' ====

tools/abipkgdiff.cc

@@ -152,6 +152,10 @@ using abigail::xml_writer::create_write_context;
 using abigail::xml_writer::write_context_sptr;
 using abigail::xml_writer::write_corpus;
 
+class package;
+
+/// Convenience typedef for a shared pointer to a @ref package.
+typedef shared_ptr<package> package_sptr;
 
 /// The options passed to the current program.
 class options
@@ -202,6 +206,8 @@ public:
   vector<string> suppression_paths;
   vector<string> kabi_whitelist_paths;
   suppressions_type kabi_suppressions;
+  package_sptr  pkg1;
+  package_sptr  pkg2;
 
   options(const string& program_name)
     : prog_name(program_name),
@@ -302,11 +308,6 @@ struct abi_diff
   }
 };
 
-class package;
-
-/// Convenience typedef for a shared pointer to a @ref package.
-typedef shared_ptr<package> package_sptr;
-
 /// Abstracts a package.
 class package
 {
@@ -649,6 +650,34 @@ public:
     sorted_strings_common_prefix(elf_file_paths(), common_paths_prefix());
   }
 
+  /// Create the path of an ABI file to be associated with a given
+  /// binary.
+  ///
+  /// @param elf_file_path the path to the binary to consider.
+  ///
+  /// @param abi_file_path the resulting ABI file path.  This is set
+  /// iff the function return true.
+  ///
+  /// @return true if the ABI file path could be constructed and the
+  /// directory tree containing it could be created.  In that case,
+  /// the resulting ABI file path is set to the @p abi_file_path
+  /// output parameter.
+  bool
+  create_abi_file_path(const string &elf_file_path,
+		       string &abi_file_path) const
+  {
+    string abi_path, dir, parent;
+    if (!abigail::tools_utils::string_suffix(elf_file_path,
+					     extracted_dir_path(),
+					     abi_path))
+      return false;
+    abi_path = extracted_dir_path() + "/abixml" + abi_path + ".abi";
+    if (!abigail::tools_utils::ensure_parent_dir_created(abi_path))
+      return false;
+    abi_file_path = abi_path;
+    return true;
+  }
+
   /// Erase the content of the temporary extraction directory that has
   /// been populated by the @ref extract_package() function;
   ///
@@ -1547,10 +1576,16 @@ compare_to_self(const elf_file& elf,
   corpus_sptr reread_corp;
   string abi_file_path;
   {
-    abi_file_path = elf.path + ".abi";
+    if (!opts.pkg1->create_abi_file_path(elf.path, abi_file_path))
+      {
+	if (opts.verbose)
+	  emit_prefix("abipkgdiff", cerr)
+	    << "Could not create the directory tree to store the abi for '"
+	    << elf.path
+	    << "'\n";
+      }
     ofstream of(abi_file_path.c_str(), std::ios_base::trunc);
 
-
     {
       const abigail::xml_writer::write_context_sptr c =
 	abigail::xml_writer::create_write_context(env.get(), of);
@@ -1645,6 +1680,7 @@ compare_to_self(const elf_file& elf,
       << "Comparison against self "
       << (s == abigail::tools_utils::ABIDIFF_OK ? "SUCCEEDED" : "FAILED")
       << '\n';
+
   return s;
 }
 
@@ -1887,8 +1923,8 @@ public:
   {}
 
   /// The job performed by the current task, which is to extract its
-  /// packages in sequence.  This is job is to be performed in
-  /// parallel with other jobs of other tasks.
+  /// packages in sequence.  This job is to be performed in parallel
+  /// with other jobs of other tasks.
   virtual void
   perform()
   {
@@ -1996,19 +2032,16 @@ public:
       {
 	string diagnostic =
 	  abigail::dwarf_reader::status_to_diagnostic_string(detailed_status);
+	if (diagnostic.empty())
+	  diagnostic =
+	    "Unknown error.  Please run the tool again with --verbose\n";
 
-	if (!diagnostic.empty())
-	  {
-	    string name = args->elf1.name;
-
-	    pretty_output +=
-	      "==== Error happened during processing of " + name + ": ====\n";
-
-	    pretty_output += diagnostic;
-
-	    pretty_output +=
-	      "==== End of error for " + name + " ====\n";
-	  }
+	string name = args->elf1.name;
+	pretty_output +=
+	  "==== Error happened during processing of '" + name + "' ====\n";
+	pretty_output += diagnostic;
+	pretty_output +=
+	  "==== End of error for '" + name + "' ====\n";
       }
   }
 }; // end class compare_task
@@ -2066,18 +2099,17 @@ public:
 	string diagnostic =
 	  abigail::dwarf_reader::status_to_diagnostic_string(detailed_status);
 
-	if (!diagnostic.empty())
-	  {
-	    string name = args->elf1.name;
+	if (diagnostic.empty())
+	  diagnostic =
+	    "Unknown error.  Please run the tool again with --verbose\n";
 
-	    pretty_output +=
-	      "==== Error happened during self check of " + name + ": ====\n";
+	string name = args->elf1.name;
+	pretty_output +=
+	  "==== Error happened during self check of '" + name + "' ====\n";
+	pretty_output += diagnostic;
+	pretty_output +=
+	  "==== SELF CHECK FAILED for '" + name + "' ====\n";
 
-	    pretty_output += diagnostic;
-
-	    pretty_output +=
-	      "==== SELF CHECK FAILED for " + name + " ====\n";
-	  }
       }
   }
 }; // end class self_compare
@@ -3430,6 +3462,8 @@ main(int argc, char* argv[])
   package_sptr first_package(new package(opts.package1, "package1"));
 
   package_sptr second_package(new package(opts.package2, "package2"));
+  opts.pkg1 = first_package;
+  opts.pkg2 = second_package;
 
   for (vector<string>::const_iterator p = opts.debug_packages1.begin();
        p != opts.debug_packages1.end();