libabigail/include/abg-corpus.h
Jose E. Marchesi via Libabigail 8c22f5fdc9 Add support for the CTF debug format to libabigail.
CTF (C Type Format) is a lightweight debugging format that provides
information about C types and the association between functions and
data symbols and types.  It is designed to be very compact and
simple.  More can be learned about it at https://ctfstd.org.

This patch introduces support in libabigail to extract ABI information
from CTF stored in ELF files.

A few notes on this implementation:

- The implementation is complete in terms of CTF support.  Every CTF
  feature is processed and handled to generate libabigail IR.  This
  includes basic types, typedefs, pointer, array and struct types.
  The CTF record of data objects (variables) and functions are also
  used in order to generate the corresponding libabigail IR artifacts.

- The decoding of CTF data is done using the libctf library which is
  part of binutils.  In order to link with it, binutils shall be built
  with --enable-shared for libctf.so to become available.

- This initial implementation is aimed to simplicity.  We have not
  tried to resolve any and every corner case that may require special
  handling.  We have observed that the DWARF front-end (which is
  naturally way more complex as the scope is way bigger) is plagued
  with hacks to handle such situations.  However, for the CTF support
  we prefer to proceed in a simpler and more modest way: we will
  handle these problems if/when we find them.  The fact that CTF only
  supports C (currently) certainly helps there.

- Likewise, in this basic support we are not handling symbol
  suppressions or other goodies that libabigail provides.  We are new
  to libabigail and ABI analysis, and at this point we simply don't
  have a clear picture about what is most useful/relevant to support
  or not.  With the maintainer's blesssing, we will tackle that
  functionaly after this basic support is applied upstream.

- The implementation in abg-ctf-reader.{cc,h} is pretty much
  self-contained.  As a result there is some duplication in terms of
  ELF handling with the DWARF reader, but since that logic is very
  simple and can be easily implemented, we don't consider this to be a
  big deal (for now.)  Hopefully the maintainers agree.

- The libabigail tools assume that ELF means to always use DWARF to
  generate the ABI IR.  We added a new command-line option --ctf to
  the tools in order to make them to use the CTF debug info instead.
  We are definitely not sure whether this is the best user interface.
  In fact I would be suprised if it was ;)

- We added support for --ctf to both abilint and abidiff.   We are not
  sure whether it would make sense to add support for CTF to the other
  tools.  Feedback welcome.

- We are pondering about what to do in terms of testing.  We have
  cursory tested this implementation using abilint and abidiff.  We
  know we are generating IR corpus that seem to be ok.  It would be
  good however to be able to run the libabigail testsuites using CTF.
  However the testsuites may need some non-trivial changes in order to
  make this possible.  Let's talk about that :)

	* configure.ac: Check for libctf.
	* src/abg-ctf-reader.cc: New file.
	* include/abg-ctf-reader.h: Likewise.
	* src/Makefile.am (libabigail_la_SOURCES): Add abg-ctf-reader.cc
	conditionally.
	* include/Makefile.am (pkginclude_HEADERS): Add abg-ctf-reader.h
	conditionally.
	* tools/abilint.cc (struct options): New option `use_ctf'.
	(display_usage): Documentation for --ctf.
	(parse_command_line): Handle --ctf.
	(main): Honour --ctf.
	* tools/abidiff.cc (struct options): New option `use_ctf'.
	(display_usage): Documentation for --ctf.
	(parse_command_line): Handle --ctf.
	(main): Honour --ctf.
	* doc/manuals/abidiff.rst: Document --ctf.
	* doc/manuals/abilint.rst: Likewise.

Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Signed-off-by: Dodji Seketeli <dodji@redhat.com>
2021-11-02 12:43:14 +01:00

401 lines
8.2 KiB
C++

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
// -*- mode: C++ -*-
//
// Copyright (C) 2013-2020 Red Hat, Inc.
/// @file
#ifndef __ABG_CORPUS_H__
#define __ABG_CORPUS_H__
#include <abg-ir.h>
namespace abigail
{
namespace ir
{
/// This is the abstraction of a set of translation units (themselves
/// seen as bundles of unitary abi artefacts like types and decls)
/// bundled together as a corpus. A corpus is thus the Application
/// binary interface of a program, a library or just a set of modules
/// put together.
class corpus
{
public:
/// A convenience typedef for std::vector<string>.
typedef vector<string> strings_type;
/// Convenience typedef for std::vector<abigail::ir::function_decl*>
typedef vector<function_decl*> functions;
///Convenience typedef for std::vector<abigail::ir::var_decl*>
typedef vector<var_decl*> variables;
class exported_decls_builder;
/// Convenience typedef for shared_ptr<exported_decls_builder>.
typedef shared_ptr<exported_decls_builder> exported_decls_builder_sptr;
/// This abstracts where the corpus comes from. That is, either it
/// has been read from the native xml format, from DWARF or built
/// artificially using the library's API.
enum origin
{
ARTIFICIAL_ORIGIN = 0,
NATIVE_XML_ORIGIN,
DWARF_ORIGIN,
CTF_ORIGIN,
LINUX_KERNEL_BINARY_ORIGIN
};
private:
corpus();
void set_group(corpus_group*);
void init_format_version();
public:
struct priv;
std::unique_ptr<priv> priv_;
corpus(ir::environment*, const string& path= "");
virtual ~corpus();
const environment*
get_environment() const;
environment*
get_environment();
void
set_environment(environment*);
void
add(const translation_unit_sptr);
const translation_units&
get_translation_units() const;
const translation_unit_sptr
find_translation_unit(const string &path) const;
void
drop_translation_units();
type_maps&
get_types();
const type_maps&
get_types() const;
type_maps&
get_type_per_loc_map();
const type_maps&
get_type_per_loc_map() const;
virtual bool
recording_types_reachable_from_public_interface_supported();
void
record_type_as_reachable_from_public_interfaces(const type_base&);
bool
type_is_reachable_from_public_interfaces(const type_base&) const;
const vector<type_base_wptr>&
get_types_not_reachable_from_public_interfaces() const;
const corpus_group*
get_group() const;
corpus_group*
get_group();
origin
get_origin() const;
void
set_origin(origin);
string&
get_format_major_version_number() const;
void
set_format_major_version_number(const string&);
string&
get_format_minor_version_number() const;
void
set_format_minor_version_number(const string&);
string&
get_path() const;
void
set_path(const string&);
const vector<string>&
get_needed() const;
void
set_needed(const vector<string>&);
const string&
get_soname();
void
set_soname(const string&);
const string&
get_architecture_name() const;
void
set_architecture_name(const string&);
virtual bool
is_empty() const;
bool
operator==(const corpus&) const;
void
set_symtab(symtab_reader::symtab_sptr);
const symtab_reader::symtab_sptr&
get_symtab() const;
virtual const string_elf_symbols_map_type&
get_fun_symbol_map() const;
const string_elf_symbols_map_type&
get_undefined_fun_symbol_map() const;
virtual const elf_symbols&
get_sorted_fun_symbols() const;
const elf_symbols&
get_sorted_undefined_fun_symbols() const;
virtual const string_elf_symbols_map_type&
get_var_symbol_map() const;
const string_elf_symbols_map_type&
get_undefined_var_symbol_map() const;
virtual const elf_symbols&
get_sorted_var_symbols() const;
const elf_symbols&
get_sorted_undefined_var_symbols() const;
const elf_symbol_sptr
lookup_function_symbol(const string& n) const;
const elf_symbol_sptr
lookup_function_symbol(const string& symbol_name,
const elf_symbol::version& version) const;
const elf_symbol_sptr
lookup_function_symbol(const elf_symbol& symbol) const;
const elf_symbol_sptr
lookup_variable_symbol(const string& n) const;
const elf_symbol_sptr
lookup_variable_symbol(const string& symbol_name,
const elf_symbol::version& version) const;
const elf_symbol_sptr
lookup_variable_symbol(const elf_symbol& symbol) const;
virtual const functions&
get_functions() const;
const vector<function_decl*>*
lookup_functions(const string& id) const;
void
sort_functions();
virtual const variables&
get_variables() const;
void
sort_variables();
virtual const elf_symbols&
get_unreferenced_function_symbols() const;
virtual const elf_symbols&
get_unreferenced_variable_symbols() const;
vector<string>&
get_regex_patterns_of_fns_to_suppress();
const vector<string>&
get_regex_patterns_of_fns_to_suppress() const;
vector<string>&
get_regex_patterns_of_vars_to_suppress();
const vector<string>&
get_regex_patterns_of_vars_to_suppress() const;
vector<string>&
get_regex_patterns_of_fns_to_keep();
const vector<string>&
get_regex_patterns_of_fns_to_keep() const;
vector<string>&
get_sym_ids_of_fns_to_keep();
const vector<string>&
get_sym_ids_of_fns_to_keep() const;
vector<string>&
get_regex_patterns_of_vars_to_keep();
const vector<string>&
get_regex_patterns_of_vars_to_keep() const;
vector<string>&
get_sym_ids_of_vars_to_keep();
const vector<string>&
get_sym_ids_of_vars_to_keep() const;
void
maybe_drop_some_exported_decls();
exported_decls_builder_sptr
get_exported_decls_builder() const;
friend class type_base;
friend class corpus_group;
};// end class corpus.
/// Abstracts the building of the set of exported variables and
/// functions.
///
/// Given a function or variable, this type can decide if it belongs
/// to the list of exported functions and variables based on all the
/// parameters needed.
class corpus::exported_decls_builder
{
class priv;
std::unique_ptr<priv> priv_;
// Forbid default construction.
exported_decls_builder();
public:
friend class corpus;
exported_decls_builder(functions& fns,
variables& vars,
strings_type& fns_suppress_regexps,
strings_type& vars_suppress_regexps,
strings_type& fns_keep_regexps,
strings_type& vars_keep_regexps,
strings_type& sym_id_of_fns_to_keep,
strings_type& sym_id_of_vars_to_keep);
const functions&
exported_functions() const;
functions&
exported_functions();
const variables&
exported_variables() const;
variables&
exported_variables();
void
maybe_add_fn_to_exported_fns(function_decl*);
void
maybe_add_var_to_exported_vars(var_decl*);
}; //corpus::exported_decls_builder
/// Abstraction of a group of corpora.
///
/// A corpus group is a union of corpora. It provides a unified view
/// of a set of corpora. It lets you get the set of functions,
/// variables and symbols that are defined and exported by a set of
/// corpora.
class corpus_group : public corpus
{
struct priv;
std::unique_ptr<priv> priv_;
// Forbid copy
corpus_group(const corpus_group&);
public:
typedef vector<corpus_sptr> corpora_type;
corpus_group(ir::environment*, const string&);
virtual ~corpus_group();
void add_corpus(const corpus_sptr&);
const corpora_type&
get_corpora() const;
const corpus_sptr
get_main_corpus() const;
corpus_sptr
get_main_corpus();
virtual bool
is_empty() const;
virtual const corpus::functions&
get_functions() const;
virtual const corpus::variables&
get_variables() const;
virtual const string_elf_symbols_map_type&
get_var_symbol_map() const;
virtual const string_elf_symbols_map_type&
get_fun_symbol_map() const;
virtual const elf_symbols&
get_sorted_fun_symbols() const;
virtual const elf_symbols&
get_sorted_var_symbols() const;
virtual const elf_symbols&
get_unreferenced_function_symbols() const;
virtual const elf_symbols&
get_unreferenced_variable_symbols() const;
unordered_set<interned_string, hash_interned_string>*
get_public_types_pretty_representations();
virtual bool
recording_types_reachable_from_public_interface_supported();
bool
operator==(const corpus_group&) const;
}; // end class corpus_group
}// end namespace ir
}//end namespace abigail
#endif //__ABG_CORPUS_H__