binutils-gdb

Commit Graph

Author	SHA1	Message	Date
Nick Alcock	de07e349be	libctf: remove ctf_malloc, ctf_free and ctf_strdup These just get in the way of auditing for erroneous usage of strdup and add a huge irregular surface of "ctf_malloc or malloc? ctf_free or free? ctf_strdup or strdup?" ctf_malloc and ctf_free usage has not reliably matched up for many years, if ever, making the whole game pointless. Go back to malloc, free, and strdup like everyone else: while we're at it, fix a bunch of places where we weren't properly checking for OOM. This changes the interface of ctf_cuname_set and ctf_parent_name_set, which could strdup but could not return errors (like ENOMEM). New in v4. include/ * ctf-api.h (ctf_cuname_set): Can now fail, returning int. (ctf_parent_name_set): Likewise. libctf/ * ctf-impl.h (ctf_alloc): Remove. (ctf_free): Likewise. (ctf_strdup): Likewise. * ctf-subr.c (ctf_alloc): Remove. (ctf_free): Likewise. * ctf-util.c (ctf_strdup): Remove. * ctf-create.c (ctf_serialize): Use malloc, not ctf_alloc; free, not ctf_free; strdup, not ctf_strdup. (ctf_dtd_delete): Likewise. (ctf_dvd_delete): Likewise. (ctf_add_generic): Likewise. (ctf_add_function): Likewise. (ctf_add_enumerator): Likewise. (ctf_add_member_offset): Likewise. (ctf_add_variable): Likewise. (membadd): Likewise. (ctf_compress_write): Likewise. (ctf_write_mem): Likewise. * ctf-decl.c (ctf_decl_push): Likewise. (ctf_decl_fini): Likewise. (ctf_decl_sprintf): Likewise. Check for OOM. * ctf-dump.c (ctf_dump_append): Use malloc, not ctf_alloc; free, not ctf_free; strdup, not ctf_strdup. (ctf_dump_free): Likewise. (ctf_dump): Likewise. * ctf-open.c (upgrade_types_v1): Likewise. (init_types): Likewise. (ctf_file_close): Likewise. (ctf_bufopen_internal): Likewise. Check for OOM. (ctf_parent_name_set): Likewise: report the OOM to the caller. (ctf_cuname_set): Likewise. (ctf_import): Likewise. * ctf-string.c (ctf_str_purge_atom_refs): Use malloc, not ctf_alloc; free, not ctf_free; strdup, not ctf_strdup. (ctf_str_free_atom): Likewise. (ctf_str_create_atoms): Likewise. (ctf_str_add_ref_internal): Likewise. (ctf_str_remove_ref): Likewise. (ctf_str_write_strtab): Likewise.	7 years ago
Nick Alcock	99dc3ebdff	libctf: properly handle ctf_add_type of forwards and self-reffing structs The code to handle structures (and unions) that refer to themselves in ctf_add_type is extremely dodgy. It works by looking through the list of not-yet-committed types for a structure with the same name as the structure in question and assuming, if it finds it, that this must be a reference to the same type. This is a linear search that gets ever slower as the dictionary grows, requiring you to call ctf_update at intervals to keep performance tolerable: but if you do that, you run into the problem that if a forward declared before the ctf_update is changed to a structure afterwards, ctf_update explodes. The last commit fixed most of this: this commit can use it, adding a new ctf_add_processing hash that tracks source type IDs that are currently being processed and uses it to avoid infinite recursion rather than the dynamic type list: we split ctf_add_type into a ctf_add_type_internal, so that ctf_add_type itself can become a wrapper that empties out this being-processed hash once the entire recursive type addition is over. Structure additions themselves avoid adding their dependent types quite so much by checking the type mapping and avoiding re-adding types we already know we have added. We also add support for adding forwards to dictionaries that already contain the thing they are a forward to: we just silently return the original type. v4: return existing struct/union/enum types properly, rather than using an uninitialized variable: shrinks sizes of CTF sections back down to roughly where they were in v1/v2 of this patch series. v5: fix tabdamage. libctf/ * ctf-impl.h (ctf_file_t) <ctf_add_processing>: New. * ctf-open.c (ctf_file_close): Free it. * ctf-create.c (ctf_serialize): Adjust. (membcmp): When reporting a conflict due to an error, report the error. (ctf_add_type): Turn into a ctf_add_processing wrapper. Rename to... (ctf_add_type_internal): ... this. Hand back types we are already in the middle of adding immediately. Hand back structs/unions with the same number of members immediately. Do not walk the dynamic list. Call ctf_add_type_internal, not ctf_add_type. Handle forwards promoted to other types and the inverse case identically. Add structs to the mapping as soon as we intern them, before they gain any members.	7 years ago
Nick Alcock	676c3ecbad	libctf: avoid the need to ever use ctf_update The method of operation of libctf when the dictionary is writable has before now been that types that are added land in the dynamic type section, which is a linked list and hash of IDs -> dynamic type definitions (and, recently a hash of names): the DTDs are a bit of CTF representing the ctf_type_t and ad hoc C structures representing the vlen. Historically, libctf was unable to do anything with these types, not even look them up by ID, let alone by name: if you wanted to do that say if you were adding a type that depended on one you just added) you called ctf_update, which serializes all the DTDs into a CTF file and reopens it, copying its guts over the fp it's called with. The ctf_updated types are then frozen in amber and unchangeable: all lookups will return the types in the static portion in preference to the dynamic portion, and we will refuse to re-add things that already exist in the static portion (and, of late, in the dynamic portion too). The libctf machinery remembers the boundary between static and dynamic types and looks in the right portion for each type. Lots of things still don't quite work with dynamic types (e.g. getting their size), but enough works to do a bunch of additions and then a ctf_update, most of the time. Except it doesn't, because ctf_add_type finds it necessary to walk the full dynamic type definition list looking for types with matching names, so it gets slower and slower with every type you add: fixing this requires calling ctf_update periodically for no other reason than to avoid massively slowing things down. This is all clunky and very slow but kind of works, until you consider that it is in fact possible and indeed necessary to modify one sort of type after it has been added: forwards. These are necessarily promoted to structs, unions or enums, and when they do so their type ID does not change. So all of a sudden we are changing types that already exist in the static portion. ctf_update gets massively confused by this and allocates space enough for the forward (with no members), but then emits the new dynamic type (with all the members) into it. You get an assertion failure after that, if you're lucky, or a coredump. So this commit rejigs things a bit and arranges to exclusively use the dynamic type definitions in writable dictionaries, and the static type definitions in readable dictionaries: we don't at any time have a mixture of static and dynamic types, and you don't need to call ctf_update to make things "appear". The ctf_dtbyname hash I introduced a few months ago, which maps things like "struct foo" to DTDs, is removed, replaced instead by a change of type of the four dictionaries which track names. Rather than just being (unresizable) ctf_hash_t's populated only at ctf_bufopen time, they are now a ctf_names_t structure, which is a pair of ctf_hash_t and ctf_dynhash_t, with the ctf_hash_t portion being used in readonly dictionaries, and the ctf_dynhash_t being used in writable ones. The decision as to which to use is centralized in the new functions ctf_lookup_by_rawname (which takes a type kind) and ctf_lookup_by_rawhash, which it calls (which takes a ctf_names_t .) This change lets us switch from using static to dynamic name hashes on the fly across the entirety of libctf without complexifying anything: in fact, because we now centralize the knowledge about how to map from type kind to name hash, it actually simplifies things and lets us throw out quite a lot of now-unnecessary complexity, from ctf_dtnyname (replaced by the dynamic half of the name tables), through to ctf_dtnextid (now that a dictionary's static portion is never referenced if the dictionary is writable, we can just use ctf_typemax to indicate the maximum type: dynamic or non-dynamic does not matter, and we no longer need to track the boundary between the types). You can now ctf_rollback() as far as you like, even past a ctf_update or for that matter a full writeout; all the iteration functions work just as well on writable as on read-only dictionaries; ctf_add_type no longer needs expensive duplicated code to run over the dynamic types hunting for ones it might be interested in; and the linker no longer needs a hack to call ctf_update so that calling ctf_add_type is not impossibly expensive. There is still a bit more complexity: some new code paths in ctf-types.c need to know how to extract information from dynamic types. This complexity will go away again in a few months when libctf acquires a proper intermediate representation. You can still call ctf_update if you like (it's public API, after all), but its only effect now is to set the point to which ctf_discard rolls back. Obviously something* still needs to serialize the CTF file before writeout, and this job is done by ctf_serialize, which does everything ctf_update used to except set the counter used by ctf_discard. It is automatically called by the various functions that do CTF writeout: nobody else ever needs to call it. With this in place, forwards that are promoted to non-forwards no longer crash the link, even if it happens tens of thousands of types later. v5: fix tabdamage. libctf/ * ctf-impl.h (ctf_names_t): New. (ctf_lookup_t) <ctf_hash>: Now a ctf_names_t, not a ctf_hash_t. (ctf_file_t) <ctf_structs>: Likewise. <ctf_unions>: Likewise. <ctf_enums>: Likewise. <ctf_names>: Likewise. <ctf_lookups>: Improve comment. <ctf_ptrtab_len>: New. <ctf_prov_strtab>: New. <ctf_str_prov_offset>: New. <ctf_dtbyname>: Remove, redundant to the names hashes. <ctf_dtnextid>: Remove, redundant to ctf_typemax. (ctf_dtdef_t) <dtd_name>: Remove. <dtd_data>: Note that the ctt_name is now populated. (ctf_str_atom_t) <csa_offset>: This is now the strtab offset for internal strings too. <csa_external_offset>: New, the external strtab offset. (CTF_INDEX_TO_TYPEPTR): Handle the LCTF_RDWR case. (ctf_name_table): New declaration. (ctf_lookup_by_rawname): Likewise. (ctf_lookup_by_rawhash): Likewise. (ctf_set_ctl_hashes): Likewise. (ctf_serialize): Likewise. (ctf_dtd_insert): Adjust. (ctf_simple_open_internal): Likewise. (ctf_bufopen_internal): Likewise. (ctf_list_empty_p): Likewise. (ctf_str_remove_ref): Likewise. (ctf_str_add): Returns uint32_t now. (ctf_str_add_ref): Likewise. (ctf_str_add_external): Now returns a boolean (int). * ctf-string.c (ctf_strraw_explicit): Check the ctf_prov_strtab for strings in the appropriate range. (ctf_str_create_atoms): Create the ctf_prov_strtab. Detect OOM when adding the null string to the new strtab. (ctf_str_free_atoms): Destroy the ctf_prov_strtab. (ctf_str_add_ref_internal): Add make_provisional argument. If make_provisional, populate the offset and fill in the ctf_prov_strtab accordingly. (ctf_str_add): Return the offset, not the string. (ctf_str_add_ref): Likewise. (ctf_str_add_external): Return a success integer. (ctf_str_remove_ref): New, remove a single ref. (ctf_str_count_strtab): Do not count the initial null string's length or the existence or length of any unreferenced internal atoms. (ctf_str_populate_sorttab): Skip atoms with no refs. (ctf_str_write_strtab): Populate the nullstr earlier. Add one to the cts_len for the null string, since it is no longer done in ctf_str_count_strtab. Adjust for csa_external_offset rename. Populate the csa_offset for both internal and external cases. Flush the ctf_prov_strtab afterwards, and reset the ctf_str_prov_offset. * ctf-create.c (ctf_grow_ptrtab): New. (ctf_create): Call it. Initialize new fields rather than old ones. Tell ctf_bufopen_internal that this is a writable dictionary. Set the ctl hashes and data model. (ctf_update): Rename to... (ctf_serialize): ... this. Leave a compatibility function behind. Tell ctf_simple_open_internal that this is a writable dictionary. Pass the new fields along from the old dictionary. Drop ctf_dtnextid and ctf_dtbyname. Use ctf_strraw, not dtd_name. Do not zero out the DTD's ctt_name. (ctf_prefixed_name): Rename to... (ctf_name_table): ... this. No longer return a prefixed name: return the applicable name table instead. (ctf_dtd_insert): Use it, and use the right name table. Pass in the kind we're adding. Migrate away from dtd_name. (ctf_dtd_delete): Adjust similarly. Remove the ref to the deleted ctt_name. (ctf_dtd_lookup_type_by_name): Remove. (ctf_dynamic_type): Always return NULL on read-only dictionaries. No longer check ctf_dtnextid: check ctf_typemax instead. (ctf_snapshot): No longer use ctf_dtnextid: use ctf_typemax instead. (ctf_rollback): Likewise. No longer fail with ECTF_OVERROLLBACK. Use ctf_name_table and the right name table, and migrate away from dtd_name as in ctf_dtd_delete. (ctf_add_generic): Pass in the kind explicitly and pass it to ctf_dtd_insert. Use ctf_typemax, not ctf_dtnextid. Migrate away from dtd_name to using ctf_str_add_ref to populate the ctt_name. Grow the ptrtab if needed. (ctf_add_encoded): Pass in the kind. (ctf_add_slice): Likewise. (ctf_add_array): Likewise. (ctf_add_function): Likewise. (ctf_add_typedef): Likewise. (ctf_add_reftype): Likewise. Initialize the ctf_ptrtab, checking ctt_name rather than dtd_name. (ctf_add_struct_sized): Pass in the kind. Use ctf_lookup_by_rawname, not ctf_hash_lookup_type / ctf_dtd_lookup_type_by_name. (ctf_add_union_sized): Likewise. (ctf_add_enum): Likewise. (ctf_add_enum_encoded): Likewise. (ctf_add_forward): Likewise. (ctf_add_type): Likewise. (ctf_compress_write): Call ctf_serialize: adjust for ctf_size not being initialized until after the call. (ctf_write_mem): Likewise. (ctf_write): Likewise. * ctf-archive.c (arc_write_one_ctf): Likewise. * ctf-lookup.c (ctf_lookup_by_name): Use ctf_lookuup_by_rawhash, not ctf_hash_lookup_type. (ctf_lookup_by_id): No longer check the readonly types if the dictionary is writable. * ctf-open.c (init_types): Assert that this dictionary is not writable. Adjust to use the new name hashes, ctf_name_table, and ctf_ptrtab_len. GNU style fix for the final ptrtab scan. (ctf_bufopen_internal): New 'writable' parameter. Flip on LCTF_RDWR if set. Drop out early when dictionary is writable. Split the ctf_lookups initialization into... (ctf_set_cth_hashes): ... this new function. (ctf_simple_open_internal): Adjust. New 'writable' parameter. (ctf_simple_open): Adjust accordingly. (ctf_bufopen): Likewise. (ctf_file_close): Destroy the appropriate name hashes. No longer destroy ctf_dtbyname, which is gone. (ctf_getdatasect): Remove spurious "extern". * ctf-types.c (ctf_lookup_by_rawname): New, look up types in the specified name table, given a kind. (ctf_lookup_by_rawhash): Likewise, given a ctf_names_t . (ctf_member_iter): Add support for iterating over the dynamic type list. (ctf_enum_iter): Likewise. (ctf_variable_iter): Likewise. (ctf_type_rvisit): Likewise. (ctf_member_info): Add support for types in the dynamic type list. (ctf_enum_name): Likewise. (ctf_enum_value): Likewise. (ctf_func_type_info): Likewise. (ctf_func_type_args): Likewise. ctf-link.c (ctf_accumulate_archive_names): No longer call ctf_update. (ctf_link_write): Likewise. (ctf_link_intern_extern_string): Adjust for new ctf_str_add_external return value. (ctf_link_add_strtab): Likewise. * ctf-util.c (ctf_list_empty_p): New.	7 years ago
Nick Alcock	791915db42	libctf: handle nonrepresentable types at link time GCC can emit references to type 0 to indicate that this type is one that is not representable in the version of CTF it emits (for instance, version 3 cannot encode vector types). Type 0 is already used in the function section to indicate padding inserted to skip functions we do not want to encode the type of, so using zero in this way is a good extension of the format: but libctf reports such types as ECTF_BADID, which is indistinguishable from file corruption via links to truly nonexistent types with IDs like 0xDEADBEEF etc, which we really do want to stop for. In particular, this stops all traversals of types dead at this point, preventing us from even dumping CTF files containing unrepresentable types to see what's going on! So add a new error, ECTF_NONREPRESENTABLE, which is returned by recursive type resolution when a reference to a zero type is found. (No zero type is ever emitted into the CTF file by GCC, only references to one). We can't do much with types that are ultimately nonrepresentable, but we can do enough to keep functioning. Adjust ctf_add_type to ensure that top-level types of type zero and structure and union members of ultimate type zero are simply skipped without reporting an error, so we can copy structures and unions that contain nonrepresentable members (skipping them and leaving a hole where they would be, so no consumers downstream of the linker need to worry about this): adjust the dumper so that we dump members of nonrepresentable types in a simple form that indicates nonrepresentability rather than terminating the dump, and do not falsely assume all errors to be -ENOMEM: adjust the linker so that types that fail to get added are simply skipped, so that both nonrepresentable types and outright errors do not terminate the type addition, which could skip many valid types and cause further errors when variables of those types are added. In future, when we gain the ability to call back to the linker to report link-time type resolution errors, we should report failures to add all but nonrepresentable types. But we can't do that yet. v5: Fix tabdamage. include/ * ctf-api.h (ECTF_NONREPRESENTABLE): New. libctf/ * ctf-types.c (ctf_type_resolve): Return ECTF_NONREPRESENTABLE on type zero. * ctf-create.c (ctf_add_type): Detect and skip nonrepresentable members and types. (ctf_add_variable): Likewise for variables pointing to them. * ctf-link.c (ctf_link_one_type): Do not warn for nonrepresentable type link failure, but do warn for others. * ctf-dump.c (ctf_dump_format_type): Likewise. Do not assume all errors to be ENOMEM. (ctf_dump_member): Likewise. (ctf_dump_type): Likewise. (ctf_dump_header_strfield): Do not assume all errors to be ENOMEM. (ctf_dump_header_sectfield): Do not assume all errors to be ENOMEM. (ctf_dump_header): Likewise. (ctf_dump_label): likewise. (ctf_dump_objts): likewise. (ctf_dump_funcs): likewise. (ctf_dump_var): likewise. (ctf_dump_str): Likewise.	7 years ago
Nick Alcock	5de9eada3b	libctf: teach ctf_add_type how forwards work This machinery has been broken for as long as Solaris has existed. Forwards are meant to encode "struct foo;", "enum foo;" or "union foo;". Obviously these all exist in distinct namespaces, so forwards store the type kind they forward to in their ctt_type member (which makes conceptual sense if you squint at it). The addition machinery uses this to promote forwards to the appropriate type as needed. Unfortunately ctf_add_type does not: it checks the global namespace (which is always wrong), and so fails with a spurious conflict if you have, say, a typedef and then a forward comes along with the same name, even if it's a forward to something like a struct. (This was observed with <libio.h>, which has "struct _IO_FILE;" and also "typedef struct _IO_FILE _IO_FILE"). We should look at the recorded type kind and look in the appropriate namespace. We should also, when creating the forward in the new container, use that type kind, rather than just defaulting to CTF_K_STRUCT and hoping that what eventually comes along is a struct. This bug is as old as the first implementation of ctf_add_type in Solaris. But we also want a new feature for the linker, closely-related and touching the same code so we add it here: not only do we want a forward followed by a struct/union/enum to promote the forward, but we want want a struct/union/enum followed by a forward to act as a NOP and return the existing type, because when we're adding many files in succession to a target link, there will often be already-promoted forwards (in the shape of a struct/union/enum) that want to unify with duplicate forwards coming from other object files. v5: fix tabdamage. libctf/ * ctf-create.c (ctf_add_type): Look up and use the forwarded-to type kind. Allow forwards to unify with pre-existing structs/ unions/enums.	7 years ago
Nick Alcock	49ea9b450b	libctf: add CU-mapping machinery Once the deduplicator is capable of actually detecting conflicting types with the same name (i.e., not yet) we will place such conflicting types, and types that depend on them, into CTF dictionaries that are the child of the main dictionary we usually emit: currently, this will lead to the .ctf section becoming a CTF archive rather than a single dictionary, with the default-named archive member (_CTF_SECTION, or NULL) being the main shared dictionary with most of the types in it. By default, the sections are named after the compilation unit they come from (complete path and all), with the cuname field in the CTF header providing further evidence of the name without requiring the caller to engage in tiresome parsing. But some callers may not wish the mapping from input CU to output sub-dictionary to be purely CU-based. The machinery here allows this to be freely changed, in two ways: - callers can call ctf_link_add_cu_mapping to specify that a single input compilation unit should have its types placed in some other CU if they conflict: the CU will always be created, even if empty, so the consuming program can depend on its existence. You can map multiple input CUs to one output CU to force all their types to be merged together: if some of those types conflict, the behaviour is currently unspecified (the new deduplicator will specify it). - callers can call ctf_link_set_memb_name_changer to provide a function which is passed every CTF sub-dictionary name in turn (including _CTF_SECTION) and can return a new name, or NULL if no change is desired. The mapping from input to output names should not map two input names to the same output name: if this happens, the two are not merged but will result in an archive with two members with the same name (technically valid, but it's hard to access the second same-named member: you have to do an iteration over archive members). This is used by the kernel's ctfarchive machinery (not yet upstream) to encode CTF under member names like {module name}.ctf rather than .ctf.CU, but it is anticipated that other large projects may wish to have their own storage for CTF outside of .ctf sections and may wish to have new naming schemes that suit their special-purpose consumers. New in v3. v4: check for strdup failure. v5: fix tabdamage. include/ * ctf-api.h (ctf_link_add_cu_mapping): New. (ctf_link_memb_name_changer_f): New. (ctf_link_set_memb_name_changer): New. libctf/ * ctf-impl.h (ctf_file_t) <ctf_link_cu_mappping>: New. <ctf_link_memb_name_changer>: Likewise. <ctf_link_memb_name_changer_arg>: Likewise. * ctf-create.c (ctf_update): Update accordingly. * ctf-open.c (ctf_file_close): Likewise. * ctf-link.c (ctf_create_per_cu): Apply the cu mapping. (ctf_link_add_cu_mapping): New. (ctf_link_set_memb_name_changer): Likewise. (ctf_change_parent_name): New. (ctf_name_list_accum_cb_arg_t) <dynames>: New, storage for names allocated by the caller's ctf_link_memb_name_changer. <ndynames>: Likewise. (ctf_accumulate_archive_names): Call the ctf_link_memb_name_changer. (ctf_link_write): Likewise (for _CTF_SECTION only): also call ctf_change_parent_name. Free any resulting names.	7 years ago
Nick Alcock	886453cbbc	libctf: map from old to corresponding newly-added types in ctf_add_type This lets you call ctf_type_mapping (dest_fp, src_fp, src_type_id) and get told what type ID the corresponding type has in the target ctf_file_t. This works even if it was added by a recursive call, and because it is stored in the target ctf_file_t it works even if we had to add one type to multiple ctf_file_t's as part of conflicting type handling. We empty out this mapping after every archive is linked: because it maps input to output fps, and we only visit each input fp once, its contents are rendered entirely useless every time the source fp changes. v3: add several missing mapping additions. Add ctf_dynhash_empty, and empty after every input archive. v5: fix tabdamage. libctf/ * ctf-impl.h (ctf_file_t): New field ctf_link_type_mapping. (struct ctf_link_type_mapping_key): New. (ctf_hash_type_mapping_key): Likewise. (ctf_hash_eq_type_mapping_key): Likewise. (ctf_add_type_mapping): Likewise. (ctf_type_mapping): Likewise. (ctf_dynhash_empty): Likewise. * ctf-open.c (ctf_file_close): Update accordingly. * ctf-create.c (ctf_update): Likewise. (ctf_add_type): Populate the mapping. * ctf-hash.c (ctf_hash_type_mapping_key): Hash a type mapping key. (ctf_hash_eq_type_mapping_key): Check the key for equality. (ctf_dynhash_insert): Fix comment typo. (ctf_dynhash_empty): New. * ctf-link.c (ctf_add_type_mapping): New. (ctf_type_mapping): Likewise. (empty_link_type_mapping): New. (ctf_link_one_input_archive): Call it.	7 years ago
Nick Alcock	72c83edd92	libctf: add the ctf_link machinery This is the start of work on the core of the linking mechanism for CTF sections. This commit handles the type and string sections. The linker calls these functions in sequence: ctf_link_add_ctf: to add each CTF section in the input in turn to a newly-created ctf_file_t (which will appear in the output, and which itself will become the shared parent that contains types that all TUs have in common (in all link modes) and all types that do not have conflicting definitions between types (by default). Input files that are themselves products of ld -r are supported, though this is not heavily tested yet. ctf_link: called once all input files are added to merge the types in all the input containers into the output container, eliminating duplicates. ctf_link_add_strtab: called once the ELF string table is finalized and all its offsets are known, this calls a callback provided by the linker which returns the string content and offset of every string in the ELF strtab in turn: all these strings which appear in the input CTF strtab are eliminated from it in favour of the ELF strtab: equally, any strings that only appear in the input strtab will reappear in the internal CTF strtab of the output. ctf_link_shuffle_syms (not yet implemented): called once the ELF symtab is finalized, this calls a callback provided by the linker which returns information on every symbol in turn as a ctf_link_sym_t. This is then used to shuffle the function info and data object sections in the CTF section into symbol table order, eliminating the index sections which map those sections to symbol names before that point. Currently just returns ECTF_NOTYET. ctf_link_write: Returns a buffer containing either a serialized ctf_file_t (if there are no types with conflicting definitions in the object files in the link) or a ctf_archive_t containing a large ctf_file_t (the common types) and a bunch of small ones named after individual CUs in which conflicting types are found (containing the conflicting types, and all types that reference them). A threshold size above which compression takes place is passed as one parameter. (Currently, only gzip compression is supported, but I hope to add lzma as well.) Lifetime rules for this are simple: don't close the input CTF files until you've called ctf_link for the last time. We do not assume that symbols or strings passed in by the callback outlast the call to ctf_link_add_strtab or ctf_link_shuffle_syms. Right now, the duplicate elimination mechanism is the one already present as part of the ctf_add_type function, and is not particularly good: it misses numerous actual duplicates, and the conflicting-types detection hardly ever reports that types conflict, even when they do (one of them just tends to get silently dropped): it is also very slow. This will all be fixed in the next few weeks, but the fix hardly touches any of this code, and the linker does work without it, just not as well as it otherwise might. (And when no CTF section is present, there is no effect on performance, of course. So only people using a trunk GCC with not-yet-committed patches will even notice. By the time it gets upstream, things should be better.) v3: Fix error handling. v4: check for strdup failure. v5: fix tabdamage. include/ * ctf-api.h (struct ctf_link_sym): New, a symbol in flight to the libctf linking machinery. (CTF_LINK_SHARE_UNCONFLICTED): New. (CTF_LINK_SHARE_DUPLICATED): New. (ECTF_LINKADDEDLATE): New, replacing ECTF_UNUSED. (ECTF_NOTYET): New, a 'not yet implemented' message. (ctf_link_add_ctf): New, add an input file's CTF to the link. (ctf_link): New, merge the type and string sections. (ctf_link_strtab_string_f): New, callback for feeding strtab info. (ctf_link_iter_symbol_f): New, callback for feeding symtab info. (ctf_link_add_strtab): New, tell the CTF linker about the ELF strtab's strings. (ctf_link_shuffle_syms): New, ask the CTF linker to shuffle its symbols into symtab order. (ctf_link_write): New, ask the CTF linker to write the CTF out. libctf/ * ctf-link.c: New file, linking of the string and type sections. * Makefile.am (libctf_a_SOURCES): Add it. * Makefile.in: Regenerate. * ctf-impl.h (ctf_file_t): New fields ctf_link_inputs, ctf_link_outputs. * ctf-create.c (ctf_update): Update accordingly. * ctf-open.c (ctf_file_close): Likewise. * ctf-error.c (_ctf_errlist): Updated with new errors.	7 years ago
Nick Alcock	3dde2c915e	libctf: fix double-free on ctf_compress_write error path We were freeing the compressed data buffer twice if compression failed. v4: Fix commit message. v5: fix tabdamage. libctf/ * ctf-create.c (ctf_compress_write): Fix double-free.	7 years ago
Nick Alcock	5537f9b9a3	libctf: write CTF files to memory, and CTF archives to fds Before now, we've been able to write CTF files to gzFile descriptors or fds, and CTF archives to named files only. Make this a bit less irregular by allowing CTF archives to be written to fds with the new function ctf_arc_write_fd: also allow CTF files to be written to a new memory buffer via ctf_write_mem. (It would be nice to complete things by adding a new function to write CTF archives to memory, but this is too difficult to do given the short time the linker is expected to be writing them out: we will transition to a better format in format v4, though we will always support reading CTF archives that are stored in .ctf sections.) include/ * ctf-api.h (ctf_arc_write_fd): New. (ctf_write_mem): Likewise. (ctf_gzwrite): Spacing fix. libctf/ * ctf-archive.c (ctf_arc_write): Split off, and reimplement in terms of... (ctf_arc_write_fd): ... this new function. * ctf-create.c (ctf_write_mem): New.	7 years ago
Nick Alcock	d851ecd373	libctf: support getting strings from the ELF strtab The CTF file format has always supported "external strtabs", which internally are strtab offsets with their MSB on: such refs get their strings from the strtab passed in at CTF file open time: this is usually intended to be the ELF strtab, and that's what this implementation is meant to support, though in theory the external strtab could come from anywhere. This commit adds support for these external strings in the ctf-string.c strtab tracking layer. It's quite easy: we just add a field csa_offset to the atoms table that tracks all strings: this field tracks the offset of the string in the ELF strtab (with its MSB already on, courtesy of a new macro CTF_SET_STID), and adds a new function that sets the csa_offset to the specified offset (plus MSB). Then we just need to avoid writing out strings to the internal strtab if they have csa_offset set, and note that the internal strtab is shorter than it might otherwise be. (We could in theory save a little more time here by eschewing sorting such strings, since we never actually write the strings out anywhere, but that would mean storing them separately and it's just not worth the complexity cost until profiling shows it's worth doing.) We also have to go through a bit of extra effort at variable-sorting time. This was previously using direct references to the internal strtab: it couldn't use ctf_strptr or ctf_strraw because the new strtab is not yet ready to put in its usual field (in a ctf_file_t that hasn't even been allocated yet at this stage): but now we're using the external strtab, this will no longer do because it'll be looking things up in the wrong strtab, with disastrous results. Instead, pass the new internal strtab in to a new ctf_strraw_explicit function which is just like ctf_strraw except you can specify a ne winternal strtab to use. But even now that it is using a new internal strtab, this is not quite enough: it can't look up strings in the external strtab because ld hasn't written it out yet, and when it does will write it straight to disk. Instead, when we write the internal strtab, note all the offset -> string mappings that we have noted belong in the external strtab to a new "synthetic external strtab" dynhash, ctf_syn_ext_strtab, and look in there at ctf_strraw time if it is set. This uses minimal extra memory (because only strings in the external strtab that we actually use are stored, and even those come straight out of the atoms table), but let both variable sorting and name interning when ctf_bufopen is next called work fine. (This also means that we don't need to filter out spurious ECTF_STRTAB warnings from ctf_bufopen but can pass them back to the caller, once we wrap ctf_bufopen so that we have a new internal variant of ctf_bufopen etc that we can pass the synthetic external strtab to. That error has been filtered out since the days of Solaris libctf, which didn't try to handle the problem of getting external strtabs right at construction time at all.) v3: add the synthetic strtab and all associated machinery. v5: fix tabdamage. include/ * ctf.h (CTF_SET_STID): New. libctf/ * ctf-impl.h (ctf_str_atom_t) <csa_offset>: New field. (ctf_file_t) <ctf_syn_ext_strtab>: Likewise. (ctf_str_add_ref): Name the last arg. (ctf_str_add_external) New. (ctf_str_add_strraw_explicit): Likewise. (ctf_simple_open_internal): Likewise. (ctf_bufopen_internal): Likewise. * ctf-string.c (ctf_strraw_explicit): Split from... (ctf_strraw): ... here, with new support for ctf_syn_ext_strtab. (ctf_str_add_ref_internal): Return the atom, not the string. (ctf_str_add): Adjust accordingly. (ctf_str_add_ref): Likewise. Move up in the file. (ctf_str_add_external): New: update the csa_offset. (ctf_str_count_strtab): Only account for strings with no csa_offset in the internal strtab length. (ctf_str_write_strtab): If the csa_offset is set, update the string's refs without writing the string out, and update the ctf_syn_ext_strtab. Make OOM handling less ugly. * ctf-create.c (struct ctf_sort_var_arg_cb): New. (ctf_update): Handle failure to populate the strtab. Pass in the new ctf_sort_var arg. Adjust for ctf_syn_ext_strtab addition. Call ctf_simple_open_internal, not ctf_simple_open. (ctf_sort_var): Call ctf_strraw_explicit rather than looking up strings by hand. * ctf-hash.c (ctf_hash_insert_type): Likewise (but using ctf_strraw). Adjust to diagnose ECTF_STRTAB nonetheless. * ctf-open.c (init_types): No longer filter out ECTF_STRTAB. (ctf_file_close): Destroy the ctf_syn_ext_strtab. (ctf_simple_open): Rename to, and reimplement as a wrapper around... (ctf_simple_open_internal): ... this new function, which calls ctf_bufopen_internal. (ctf_bufopen): Rename to, and reimplement as a wrapper around... (ctf_bufopen_internal): ... this new function, which sets ctf_syn_ext_strtab.	7 years ago
Nick Alcock	fd55eae84d	libctf: allow the header to change between versions libctf supports dynamic upgrading of the type table as file format versions change, but before now has not supported changes to the CTF header. Doing this is complicated by the baroque storage method used: the CTF header is kept prepended to the rest of the CTF data, just as when read from the file, and written out from there, and is endian-flipped in place. This makes accessing it needlessly hard and makes it almost impossible to make the header larger if we add fields. The general storage machinery around the malloced ctf pointer (the 'ctf_base') is also overcomplicated: the pointer is sometimes malloced locally and sometimes assigned from a parameter, so freeing it requires checking to see if that parameter was used, needlessly coupling ctf_bufopen and ctf_file_close together. So split the header out into a new ctf_file_t.ctf_header, which is written out explicitly: squeeze it out of the CTF buffer whenever we reallocate it, and use ctf_file_t.ctf_buf to skip past the header when we do not need to reallocate (when no upgrading or endian-flipping is required). We now track whether the CTF base can be freed explicitly via a new ctf_dynbase pointer which is non-NULL only when freeing is possible. With all this done, we can upgrade the header on the fly and add new fields as desired, via a new upgrade_header function in ctf-open. As with other forms of upgrading, libctf upgrades older headers automatically to the latest supported version at open time. For a first use of this field, we add a new string field cth_cuname, and a corresponding setter/getter pair ctf_cuname_set and ctf_cuname: this is used by debuggers to determine whether a CTF section's types relate to a single compilation unit, or to all compilation units in the program. (Types with ambiguous definitions in different CUs have only one of these types placed in the top-level shared .ctf container: the rest are placed in much smaller per-CU containers, which have the shared container as their parent. Since CTF must be useful in the absence of DWARF, we store the names of the relevant CUs ourselves, so the debugger can look them up.) v5: fix tabdamage. include/ * ctf-api.h (ctf_cuname): New function. (ctf_cuname_set): Likewise. * ctf.h: Improve comment around upgrading, no longer implying that v2 is the target of upgrades (it is v3 now). (ctf_header_v2_t): New, old-format header for backward compatibility. (ctf_header_t): Add cth_cuname: this is the first of several header changes in format v3. libctf/ * ctf-impl.h (ctf_file_t): New fields ctf_header, ctf_dynbase, ctf_cuname, ctf_dyncuname: ctf_base and ctf_buf are no longer const. * ctf-open.c (ctf_set_base): Preserve the gap between ctf_buf and ctf_base: do not assume that it is always sizeof (ctf_header_t). Print out ctf_cuname: only print out ctf_parname if set. (ctf_free_base): Removed, ctf_base is no longer freed: free ctf_dynbase instead. (ctf_set_version): Fix spacing. (upgrade_header): New, in-place header upgrading. (upgrade_types): Rename to... (upgrade_types_v1): ... this. Free ctf_dynbase, not ctf_base. No longer track old and new headers separately. No longer allow for header sizes explicitly: squeeze the headers out on upgrade (they are preserved in fp->ctf_header). Set ctf_dynbase, ctf_base and ctf_buf explicitly. Use ctf_free, not ctf_free_base. (upgrade_types): New, also handle ctf_parmax updating. (flip_header): Flip ctf_cuname. (flip_types): Flip BUF explicitly rather than deriving BUF from BASE. (ctf_bufopen): Store the header in fp->ctf_header. Correct minimum required alignment of objtoff and funcoff. No longer store it in the ctf_buf unless that buf is derived unmodified from the input. Set ctf_dynbase where ctf_base is dynamically allocated. Drop locals that duplicate fields in ctf_file: move allocation of ctf_file further up instead. Call upgrade_header as needed. Move version-specific ctf_parmax initialization into upgrade_types. More concise error handling. (ctf_file_close): No longer test for null pointers before freeing. Free ctf_dyncuname, ctf_dynbase, and ctf_header. Do not call ctf_free_base. (ctf_cuname): New. (ctf_cuname_set): New. * ctf-create.c (ctf_update): Populate ctf_cuname. (ctf_gzwrite): Write out the header explicitly. Remove obsolescent comment. (ctf_write): Likewise. (ctf_compress_write): Get the header from ctf_header, not ctf_base. Fix the compression length: fp->ctf_size never counted the CTF header. Simplify the compress call accordingly.	7 years ago
Nick Alcock	f57cf0e3e3	libctf: fix spurious error when rolling back to the first snapshot The first ctf_snapshot called after CTF file creation yields a snapshot handle that always yields a spurious ECTF_OVERROLLBACK error ("Attempt to roll back past a ctf_update") on ctf_rollback(), even if ctf_update has never been called. The fix is to start with a ctf_snapshot value higher than the zero value that ctf_snapshot_lu ("last update CTF snapshot value") is initialized to. libctf/ * ctf-create.c (ctf_create): Fix off-by-one error.	7 years ago
Nick Alcock	f5e9c9bde0	libctf: deduplicate and sort the string table ctf.h states: > [...] the CTF string table does not contain any duplicated strings. Unfortunately this is entirely untrue: libctf has before now made no attempt whatsoever to deduplicate the string table. It computes the string table's length on the fly as it adds new strings to the dynamic CTF file, and ctf_update() just writes each string to the table and notes the current write position as it traverses the dynamic CTF file's data structures and builds the final CTF buffer. There is no global view of the strings and no deduplication. Fix this by erasing the ctf_dtvstrlen dead-reckoning length, and adding a new dynhash table ctf_str_atoms that maps unique strings to a list of references to those strings: a reference is a simple uint32_t * to some value somewhere in the under-construction CTF buffer that needs updating to note the string offset when the strtab is laid out. Adding a string is now a simple matter of calling ctf_str_add_ref(), which adds a new atom to the atoms table, if one doesn't already exist, and adding the location of the reference to this atom to the refs list attached to the atom: this works reliably as long as one takes care to only call ctf_str_add_ref() once the final location of the offset is known (so you can't call it on a temporary structure and then memcpy() that structure into place in the CTF buffer, because the ref will still point to the old location: ctf_update() changes accordingly). Generating the CTF string table is a matter of calling ctf_str_write_strtab(), which counts the length and number of elements in the atoms table using the ctf_dynhash_iter() function we just added, populating an array of pointers into the atoms table and sorting it into order (to help compressors), then traversing this table and emitting it, updating the refs to each atom as we go. The only complexity here is arranging to keep the null string at offset zero, since a lot of code in libctf depends on being able to leave strtab references at 0 to indicate 'no name'. Once the table is constructed and the refs updated, we know how long it is, so we can realloc() the partial CTF buffer we allocated earlier and can copy the table on to the end of it (and purge the refs because they're not needed any more and have been invalidated by the realloc() call in any case). The net effect of all this is a reduction in uncompressed strtab sizes of about 30% (perhaps a quarter to a half of all strings across the Linux kernel are eliminated as duplicates). Of course, duplicated strings are highly redundant, so the space saving after compression is only about 20%: when the other non-strtab sections are factored in, CTF sizes shrink by about 10%. No change in externally-visible API or file format (other than the reduction in pointless redundancy). libctf/ * ctf-impl.h: (struct ctf_strs_writable): New, non-const version of struct ctf_strs. (struct ctf_dtdef): Note that dtd_data.ctt_name is unpopulated. (struct ctf_str_atom): New, disambiguated single string. (struct ctf_str_atom_ref): New, points to some other location that references this string's offset. (struct ctf_file): New members ctf_str_atoms and ctf_str_num_refs. Remove member ctf_dtvstrlen: we no longer track the total strlen as we add strings. (ctf_str_create_atoms): Declare new function in ctf-string.c. (ctf_str_free_atoms): Likewise. (ctf_str_add): Likewise. (ctf_str_add_ref): Likewise. (ctf_str_purge_refs): Likewise. (ctf_str_write_strtab): Likewise. (ctf_realloc): Declare new function in ctf-util.c. * ctf-open.c (ctf_bufopen): Create the atoms table. (ctf_file_close): Destroy it. * ctf-create.c (ctf_update): Copy-and-free it on update. No longer special-case the position of the parname string. Construct the strtab by calling ctf_str_add_ref and ctf_str_write_strtab after the rest of each buffer element is constructed, not via open-coding: realloc the CTF buffer and append the strtab to it. No longer maintain ctf_dtvstrlen. Sort the variable entry table later, after strtab construction. (ctf_copy_membnames): Remove: integrated into ctf_copy_{s,l,e}members. (ctf_copy_smembers): Drop the string offset: call ctf_str_add_ref after buffer element construction instead. (ctf_copy_lmembers): Likewise. (ctf_copy_emembers): Likewise. (ctf_create): No longer maintain the ctf_dtvstrlen. (ctf_dtd_delete): Likewise. (ctf_dvd_delete): Likewise. (ctf_add_generic): Likewise. (ctf_add_enumerator): Likewise. (ctf_add_member_offset): Likewise. (ctf_add_variable): Likewise. (membadd): Likewise. * ctf-util.c (ctf_realloc): New, wrapper around realloc that aborts if there are active ctf_str_num_refs. (ctf_strraw): Move to ctf-string.c. (ctf_strptr): Likewise. * ctf-string.c: New file, strtab manipulation. * Makefile.am (libctf_a_SOURCES): Add it. * Makefile.in: Regenerate.	7 years ago
Nick Alcock	65365aa856	libctf: drop mmap()-based CTF data allocator This allocator has the ostensible benefit that it lets us mprotect() the memory used for CTF storage: but in exchange for this it adds considerable complexity, since we have to track allocation sizes ourselves for use at freeing time, note whether the data we are storing was ctf_data_alloc()ed or not so we know if we can safely mprotect() it... and while the mprotect()ing has found few bugs, it has been the cause of more than one due to errors in all this tracking leading to us mprotect()ing bits of the heap and stuff like that. We are about to start composing CTF buffers from pieces so that we can do usage-based optimizations on the strtab. This means we need realloc(), which needs nonportable mremap() and more tracking of the original allocation size, and the complexity and bureaucracy of all of this is just too high for its negligible benefits. Drop the whole thing and just use malloc() like everyone else. It knows better than we do when it is safe to use mmap() under the covers, anyway. While we're at it, don't leak the entire buffer if ctf_compress_write() fails to compress it. libctf/ * ctf-subr.c (_PAGESIZE): Remove. (ctf_data_alloc): Likewise. (ctf_data_free): Likewise. (ctf_data_protect): Likewise. * ctf-impl.h: Remove declarations. * ctf-create.c (ctf_update): No longer call ctf_data_protect: use ctf_free, not ctf_data_free. (ctf_compress_write): Use ctf_data_alloc, not ctf_alloc. Free the buffer again on compression error. * ctf-open.c (ctf_set_base): No longer track the size: call ctf_free, not ctf_data_free. (upgrade_types): Likewise. Call ctf_alloc, not ctf_data_alloc. (ctf_bufopen): Likewise. No longer call ctf_data_protect.	7 years ago
Nick Alcock	2486542803	libctf: handle errors on dynhash insertion better We were missing several cases where dynhash insertion might fail, likely due to OOM but possibly for other reasons. Pass the errors on. libctf/ * ctf-create.c (ctf_dtd_insert): Pass on error returns from ctf_dynhash_insert. (ctf_dvd_insert): Likewise. (ctf_add_generic): Likewise. (ctf_add_variable): Likewise. * ctf-impl.h: Adjust declarations.	7 years ago
Nick Alcock	62d8e3b731	libctf: eschew %zi format specifier Too many platforms don't support it, and we can always safely use %lu or %li anyway, because the only uses are in debugging output. libctf/ * ctf-archive.c (ctf_arc_write): Eschew %zi format specifier. (ctf_arc_open_by_offset): Likewise. * ctf-create.c (ctf_add_type): Likewise.	7 years ago
Tom Tromey	76fad99963	Use CHAR_BIT instead of NBBY in libctf On x86-64 Fedora 29, I tried to build a mingw-hosted gdb that targets ppc-linux. You can do this with: ../binutils-gdb/configure --host=i686-w64-mingw32 --target=ppc-linux \ --disable-{binutils,gas,gold,gprof,ld} The build failed with these errors in libctf: In file included from ../../binutils-gdb/libctf/ctf-create.c:20: ../../binutils-gdb/libctf/ctf-create.c: In function 'ctf_add_encoded': ../../binutils-gdb/libctf/ctf-create.c:803:59: error: 'NBBY' undeclared (first use in this function) dtd->dtd_data.ctt_size = clp2 (P2ROUNDUP (ep->cte_bits, NBBY) / NBBY); ^~~~ ../../binutils-gdb/libctf/ctf-impl.h:254:42: note: in definition of macro 'P2ROUNDUP' #define P2ROUNDUP(x, align) (-(-(x) & -(align))) ^~~~~ ../../binutils-gdb/libctf/ctf-create.c:803:59: note: each undeclared identifier is reported only once for each function it appears in dtd->dtd_data.ctt_size = clp2 (P2ROUNDUP (ep->cte_bits, NBBY) / NBBY); ^~~~ ../../binutils-gdb/libctf/ctf-impl.h:254:42: note: in definition of macro 'P2ROUNDUP' #define P2ROUNDUP(x, align) (-(-(x) & -(align))) ^~~~~ ../../binutils-gdb/libctf/ctf-create.c: In function 'ctf_add_slice': ../../binutils-gdb/libctf/ctf-create.c:862:59: error: 'NBBY' undeclared (first use in this function) dtd->dtd_data.ctt_size = clp2 (P2ROUNDUP (ep->cte_bits, NBBY) / NBBY); ^~~~ ../../binutils-gdb/libctf/ctf-impl.h:254:42: note: in definition of macro 'P2ROUNDUP' #define P2ROUNDUP(x, align) (-(-(x) & -(align))) ^~~~~ ../../binutils-gdb/libctf/ctf-create.c: In function 'ctf_add_member_offset': ../../binutils-gdb/libctf/ctf-create.c:1341:21: error: 'NBBY' undeclared (first use in this function) off += lsize * NBBY; ^~~~ ../../binutils-gdb/libctf/ctf-create.c: In function 'ctf_add_type': ../../binutils-gdb/libctf/ctf-create.c:1822:16: warning: unknown conversion type character 'z' in format [-Wformat=] ctf_dprintf ("Conflict for type %s against ID %lx: " ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../../binutils-gdb/libctf/ctf-create.c:1823:35: note: format string is defined here "union size differs, old %zi, new %zi\n", ^ ../../binutils-gdb/libctf/ctf-create.c:1822:16: warning: unknown conversion type character 'z' in format [-Wformat=] ctf_dprintf ("Conflict for type %s against ID %lx: " ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../../binutils-gdb/libctf/ctf-create.c:1823:44: note: format string is defined here "union size differs, old %zi, new %zi\n", ^ ../../binutils-gdb/libctf/ctf-create.c:1822:16: warning: too many arguments for format [-Wformat-extra-args] ctf_dprintf ("Conflict for type %s against ID %lx: " ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ This patch fixes the actual errors in here. I did not try to fix the printf warnings, though I think someone ought to. Ok? libctf/ChangeLog 2019-06-04 Tom Tromey <tromey@adacore.com> * ctf-create.c (ctf_add_encoded, ctf_add_slice) (ctf_add_member_offset): Use CHAR_BIT, not NBBY.	7 years ago
Nick Alcock	6b22174ff1	libctf: look for BSD versus GNU qsort_r signatures We cannot just look for any declaration of qsort_r, because some operating systems have a qsort_r that has a different prototype but which still has a pair of pointers in the right places (the last two args are interchanged): so use AC_LINK_IFELSE to check for both known variants of qsort_r(), and swap their args into a consistent order in a suitable inline function. (The code for this is taken almost unchanged from gnulib.) (Now we are not using AC_LIBOBJ any more, we can use a better name for the qsort_r replacement as well.) libctf/ * qsort_r.c: Rename to... * ctf-qsort_r.c: ... this. (_quicksort): Define to ctf_qsort_r. * ctf-decls.h (qsort_r): Remove. (ctf_qsort_r): Add. (struct ctf_qsort_arg): New, transport the real ARG and COMPAR. (ctf_qsort_compar_thunk): Rearrange the arguments to COMPAR. * Makefile.am (libctf_a_LIBADD): Remove. (libctf_a_SOURCES): New, add ctf-qsort_r.c. * ctf-archive.c (ctf_arc_write): Call ctf_qsort_r, not qsort_r. * ctf-create.c (ctf_update): Likewise. * configure.ac: Check for BSD versus GNU qsort_r signature. * Makefile.in: Regenerate. * config.h.in: Likewise. * configure: Likewise.	7 years ago
Jose E. Marchesi	a0486bac41	libctf: fix a number of build problems found on Solaris and NetBSD - Use of nonportable <endian.h> - Use of qsort_r - Use of zlib without appropriate magic to pull in the binutils zlib - Use of off64_t without checking (fixed by dropping the unused fields that need off64_t entirely) - signedness problems due to long being too short a type on 32-bit platforms: ctf_id_t is now 'unsigned long', and CTF_ERR must be used only for functions that return ctf_id_t - One lingering use of bzero() and of <sys/errno.h> All fixed, using code from gnulib where possible. Relatedly, set cts_size in a couple of places it was missed (string table and symbol table loading upon ctf_bfdopen()). binutils/ * objdump.c (make_ctfsect): Drop cts_type, cts_flags, and cts_offset. * readelf.c (shdr_to_ctf_sect): Likewise. include/ * ctf-api.h (ctf_sect_t): Drop cts_type, cts_flags, and cts_offset. (ctf_id_t): This is now an unsigned type. (CTF_ERR): Cast it to ctf_id_t. Note that it should only be used for ctf_id_t-returning functions. libctf/ * Makefile.am (ZLIB): New. (ZLIBINC): Likewise. (AM_CFLAGS): Use them. (libctf_a_LIBADD): New, for LIBOBJS. * configure.ac: Check for zlib, endian.h, and qsort_r. * ctf-endian.h: New, providing htole64 and le64toh. * swap.h: Code style fixes. (bswap_identity_64): New. * qsort_r.c: New, from gnulib (with one added #include). * ctf-decls.h: New, providing a conditional qsort_r declaration, and unconditional definitions of MIN and MAX. * ctf-impl.h: Use it. Do not use <sys/errno.h>. (ctf_set_errno): Now returns unsigned long. * ctf-util.c (ctf_set_errno): Adjust here too. * ctf-archive.c: Use ctf-endian.h. (ctf_arc_open_by_offset): Use memset, not bzero. Drop cts_type, cts_flags and cts_offset. (ctf_arc_write): Drop debugging dependent on the size of off_t. * ctf-create.c: Provide a definition of roundup if not defined. (ctf_create): Drop cts_type, cts_flags and cts_offset. (ctf_add_reftype): Do not check if type IDs are below zero. (ctf_add_slice): Likewise. (ctf_add_typedef): Likewise. (ctf_add_member_offset): Cast error-returning ssize_t's to size_t when known error-free. Drop CTF_ERR usage for functions returning int. (ctf_add_member_encoded): Drop CTF_ERR usage for functions returning int. (ctf_add_variable): Likewise. (enumcmp): Likewise. (enumadd): Likewise. (membcmp): Likewise. (ctf_add_type): Likewise. Cast error-returning ssize_t's to size_t when known error-free. * ctf-dump.c (ctf_is_slice): Drop CTF_ERR usage for functions returning int: use CTF_ERR for functions returning ctf_type_id. (ctf_dump_label): Likewise. (ctf_dump_objts): Likewise. * ctf-labels.c (ctf_label_topmost): Likewise. (ctf_label_iter): Likewise. (ctf_label_info): Likewise. * ctf-lookup.c (ctf_func_args): Likewise. * ctf-open.c (upgrade_types): Cast to size_t where appropriate. (ctf_bufopen): Likewise. Use zlib types as needed. * ctf-types.c (ctf_member_iter): Drop CTF_ERR usage for functions returning int. (ctf_enum_iter): Likewise. (ctf_type_size): Likewise. (ctf_type_align): Likewise. Cast to size_t where appropriate. (ctf_type_kind_unsliced): Likewise. (ctf_type_kind): Likewise. (ctf_type_encoding): Likewise. (ctf_member_info): Likewise. (ctf_array_info): Likewise. (ctf_enum_value): Likewise. (ctf_type_rvisit): Likewise. * ctf-open-bfd.c (ctf_bfdopen): Drop cts_type, cts_flags and cts_offset. (ctf_simple_open): Likewise. (ctf_bfdopen_ctfsect): Likewise. Set cts_size properly. * Makefile.in: Regenerate. * aclocal.m4: Likewise. * config.h: Likewise. * configure: Likewise.	7 years ago
Nick Alcock	c499eb6896	libctf: type copying ctf_add_type() allows you to copy types, and all the types they depend on, from one container to another (writable) container. This lets a program maintaining multiple distinct containers (not in a parent-child relationship) introduce types that depend on types in one container in another writable one, by copying the necessary types. libctf/ * ctf-create.c (enumcmp): New. (enumadd): Likewise. (membcmp): Likewise. (membadd): Likewise. (ctf_add_type): Likewise.	7 years ago
Nick Alcock	47d546f427	libctf: creation functions The CTF creation process looks roughly like (error handling elided): int err; ctf_file_t foo = ctf_create (&err); ctf_id_t type = ctf_add_THING (foo, ...); ctf_update (foo); ctf_write (...); Some ctf_add_THING functions accept other type IDs as arguments, depending on the type: cv-quals, pointers, and structure and union members all take other types as arguments. So do 'slices', which let you take an existing integral type and recast it as a type with a different bitness or offset within a byte, for bitfields. One class of THING is not a type: "variables", which are mappings of names (in the internal string table) to types. These are mostly useful when encoding variables that do not appear in a symbol table but which some external user has some other way to figure out the address of at runtime (dynamic symbol lookup or querying a VM interpreter or something). You can snapshot the creation process at any point: rolling back to a snapshot deletes all types and variables added since that point. You can make arbitrary type queries on the CTF container during the creation process, but you must call ctf_update() first, which translates the growing dynamic container into a static one (this uses the CTF opening machinery, added in a later commit), which is quite expensive. This function must also be called after adding types and before writing the container out. Because addition of types involves looking up existing types, we add a little of the type lookup machinery here, as well: only enough to look up types in dynamic containers under construction. libctf/ * ctf-create.c: New file. * ctf-lookup.c: New file. include/ * ctf-api.h (zlib.h): New include. (ctf_sect_t): New. (ctf_sect_names_t): Likewise. (ctf_encoding_t): Likewise. (ctf_membinfo_t): Likewise. (ctf_arinfo_t): Likewise. (ctf_funcinfo_t): Likewise. (ctf_lblinfo_t): Likewise. (ctf_snapshot_id_t): Likewise. (CTF_FUNC_VARARG): Likewise. (ctf_simple_open): Likewise. (ctf_bufopen): Likewise. (ctf_create): Likewise. (ctf_add_array): Likewise. (ctf_add_const): Likewise. (ctf_add_enum_encoded): Likewise. (ctf_add_enum): Likewise. (ctf_add_float): Likewise. (ctf_add_forward): Likewise. (ctf_add_function): Likewise. (ctf_add_integer): Likewise. (ctf_add_slice): Likewise. (ctf_add_pointer): Likewise. (ctf_add_type): Likewise. (ctf_add_typedef): Likewise. (ctf_add_restrict): Likewise. (ctf_add_struct): Likewise. (ctf_add_union): Likewise. (ctf_add_struct_sized): Likewise. (ctf_add_union_sized): Likewise. (ctf_add_volatile): Likewise. (ctf_add_enumerator): Likewise. (ctf_add_member): Likewise. (ctf_add_member_offset): Likewise. (ctf_add_member_encoded): Likewise. (ctf_add_variable): Likewise. (ctf_set_array): Likewise. (ctf_update): Likewise. (ctf_snapshot): Likewise. (ctf_rollback): Likewise. (ctf_discard): Likewise. (ctf_write): Likewise. (ctf_gzwrite): Likewise. (ctf_compress_write): Likewise.	7 years ago

22 Commits (e6b39f6f8e5418ba2a237ef16460c22b49833ca6)