binutils-gdb

Commit Graph

Author	SHA1	Message	Date
Nick Alcock	987cf30ad8	libctf, binutils: initial work towards libctf gettextization We gettextize under our package name, which we change to a more reasonable 'libctf'. Our internationalization support is mostly provided by ctf-intl.h, which is a copy of opcodes/opintl.h with the non-gettext_noop N_() expansion debracketed to avoid pedantic compiler warnings. The libctf error strings returned by ctf_errmsg are marked up for internationalization. (We also adjust binutils's Makefile a tiny bit to allow for the fact that libctf now uses functions from libintl.) binutils/ChangeLog 2020-08-27 Nick Alcock <nick.alcock@oracle.com> * Makefile.am (readelf_LDADD): Move $(LIBINTL) after $(LIBCTF_NOBFD). * Makefile.in: Regenerated. libctf/ChangeLog 2020-08-27 Nick Alcock <nick.alcock@oracle.com> * configure.ac: Adjust package name to simply 'libctf': arbitrarily declare this to be version 1.2.0. * Makefile.am (AM_CPPFLAGS): Add @INCINTL@. * Makefile.in: Regenerated. * configure: Regenerated. * ctf-intl.h: New file, lightly modified from opcodes/opintl.h. * ctf-impl.h: Include it. * ctf-error.r (_ctf_errlist_t): Mark strings as noop-translatable. (ctf_errmsg): Actually translate them.	6 years ago
Nick Alcock	e148b73013	libctf: drop error-prone ctf_strerror This utility function is almost useless (all it does is casts the result of a strerror) but has a seriously confusing name. Over and over again I have accidentally called it instead of ctf_errmsg, and hidden a time-bomb for myself in a hard-to-test error-handling path: since ctf_strerror is just a strerror wrapper, it cannot handle CTF errnos, unlike ctf_errmsg. It's astonishingly lucky that none of these errors have crept into any commits to date. Fuse it into ctf_errmsg and drop it. libctf/ * ctf-impl.h (ctf_strerror): Delete. * ctf-subr.c (ctf_strerror): Likewise. * ctf-error.c (ctf_errmsg): Stop using ctf_strerror: just use strerror directly.	6 years ago
Nick Alcock	7eea9d3bdb	libctf: restructure error handling to reduce relocations Jose Marchesi noted that the traditional-Unix error array in ctf-error.c introduces one reloc per error to initialize the array: 58 so far. We can reduce this to zero using an array of carefully-sized individual members which is used to construct a string table, that is then referenced by the lookup functions: but doing this automatically is a pain. Bruno Haible wrote suitable code years ago: I got permission to reuse it (Bruno says "... which I hereby put in the public domain"); I modified it a tiny bit (similarly to what Ulrich Drepper did in the dsohowto text, but I redid it from scratch), commented it up a bit, and shifted the error table into that form, migrating it into the new file ctf-error.h. This has the advantage that it spotted both typos in the text of the errors in the comments in ctf-api.h and typos in the error defines in the comments in ctf-error.c, and places where the two were simply not in sync. All are now fixed. One new constant exists in ctf-api.h: CTF_NERR, since the old method of working out the number of errors in ctf-error.c was no longer usable, and it seems that the number of CTF errors is something users might reasonably want as well. It should be pretty easy to keep up to date as new errors are introduced. include/ * ctf-api.h (ECTF_): Improve comments. (ECTF_NERR): New. libctf/ ctf-error.c: Include <stddef.h>, for offsetof. (_ctf_errlist): Migrate to... (_ctf_errlist_t): ... this. (_ctf_erridx): New, indexes into _ctf_errlist_t. (_ctf_nerr): Remove. (ctf_errmsg): Adjust accordingly. * Makefile.am (BUILT_SOURCES): Note... (ctf-error.h): ... this new rule. * Makefile.in: Regenerate. * mkerrors.sed: New, process ctf-api.h to generate ctf-error.h. * .gitignore: New, ignore ctf-error.h.	6 years ago
Alan Modra	b3adc24a07	Update year range in copyright notice of binutils files	6 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	eabb7154df	libctf: add linking of the variable section The compiler describes the name and type of all file-scope variables in this section. Merging it at link time requires using the type mapping added in the previous commit to determine the appropriate type for the variable in the output, given its type in the input: we check the shared container first, and if the type doesn't exist there, it must be a conflicted type in the per-CU child, and the variable should go there too. We also put the variable in the per-CU child if a variable with the same name but a different type already exists in the parent: we ignore any such conflict in the child because CTF cannot represent such things, nor can they happen unless a third-party linking program has overridden the mapping of CU to CTF archive member name (using machinery added in a later commit). v3: rewritten using an algorithm that actually works in the case of conflicting names. Some code motion from the next commit. Set the per-CU parent name. v4: check for strdup failure. v5: fix tabdamage. include/ * ctf-api.h (ECTF_INTERNAL): New. libctf/ * ctf-link.c (ctf_create_per_cu): New, refactored out of... (ctf_link_one_type): ... here, with parent-name setting added. (check_variable): New. (ctf_link_one_variable): Likewise. (ctf_link_one_input_archive_member): Call it. * ctf-error.c (_ctf_errlist): Updated with new errors.	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	12a0b67d28	libctf: introduce ctf_func_type_{info,args}, ctf_type_aname_raw The first two of these allow you to get function type info and args out of the types section give a type ID: astonishingly, this was missing from libctf before now: so even though types of kind CTF_K_FUNCTION were supported, you couldn't find out anything about them. (The existing ctf_func_info and ctf_func_args only allow you to get info about functions in the function section, i.e. given symbol table indexes, not type IDs.) The second of these allows you to get the raw undecorated name out of the CTF section (strdupped for safety) without traversing subtypes to build a full C identifier out of it. It's useful for things that are already tracking the type kind etc and just need an unadorned name. include/ * ctf-api.h (ECTF_NOTFUNC): Fix description. (ctf_func_type_info): New. (ctf_func_type_args): Likewise. libctf/ * ctf-types.c (ctf_type_aname_raw): New. (ctf_func_type_info): Likewise. (ctf_func_type_args): Likewise. * ctf-error.c (_ctf_errlist): Fix description.	7 years ago
Nick Alcock	479604f44f	libctf: error handling CTF functions return zero on success or an extended errno value which can be translated into a string via the functions in this commit. The errno numbers start at -CTF_BASE. libctf/ * ctf-error.c: New file. include/ * ctf-api.h (ctf_errno): New declaration. (ctf_errmsg): Likewise.	7 years ago

9 Commits (448ba6860ec7dff6f3df6945dd4f5880bd4e265a)