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2020-07-22libctf, create: member names of "" and NULL should be the sameNick Alcock2-0/+8
This matters for the case of unnamed bitfields, whose names are the null string. These are special in that they are the only members whose "names" are allowed to be duplicated in a single struct, but we were only handling this for the case where name == NULL. Translate "" to NULL to help callers. libctf/ * ctf-create.c (ctf_add_member_offset): Support names of "" as if they were the null pointer.
2020-07-22libctf, open: drop unnecessary historical wart around forwardsNick Alcock2-9/+8
When opening, we consider a forward with a kind above the maximum allowable set of kinds and a forward of kind CTF_K_UNKNOWN to be a forward to a struct. Whatever CTF version it was that produced forwards with no associated kind, it predates anything we can read: remove this wart. libctf/ * ctf-open.c (init_types): Remove typeless CTF_K_FORWARD special-casing.
2020-07-22libctf, types: allow ctf_type_reference of dynamic slicesNick Alcock2-3/+16
One spot was missed when we rejigged ctf_update into ctf_serialize and allowed all operations on dynamic containers: ctf_type_reference of slices. A dynamic slice's vlen state is stored in the dtu_slice member, so fetch it from there. libctf/ * ctf-types.c (ctf_type_reference): Add support for dynamic slices.
2020-07-22libctf, create: add explicit casts for variables' and slices' typesNick Alcock2-2/+7
This is technically unnecessary -- the compiler is quite capable of doing the range reduction for us -- but it does mean that all assignments of a ctf_id_t to its final uint32_t representation now have appropriate explicit casts. libctf/ * ctf-create.c (ctf_serialize): Add cast. (ctf_add_slice): Likewise.
2020-07-22libctf, create: do not corrupt function types' arglists at insertion timeNick Alcock4-14/+27
ctf_add_function assumes that function types' arglists are of type ctf_id_t. Since they are CTF IDs, they are 32 bits wide, a uint32_t: unfortunately ctf_id_t is a forward-compatible user-facing 64 bits wide, and should never ever reach the CTF storage level. All the CTF code other than ctf_add_function correctly assumes that function arglists outside dynamic containers are 32 bits wide, so the serialization machinery ends up cutting off half the arglist, corrupting all args but the first (a good sign is a bunch of args of ID 0, the unimplemented type, popping up). Fix this by copying the arglist into place item by item, casting it properly, at the same time as we validate the arg types. Fix the type of the dtu_argv in the dynamic container and drop the now-unnecessary cast in the serializer. libctf/ * ctf-impl.h (ctf_dtdef_t) <dtu_argv>: Fix type. * ctf-create.c (ctf_add_function): Check for unimplemented type and populate at the same time. Populate one-by-one, not via memcpy. (ctf_serialize): Remove unnecessary cast. * ctf-types.c (ctf_func_type_info): Likewise. (ctf_func_type_args): Likewise. Fix comment typo.
2020-07-22libctf, create: support addition of references to the unimplemented typeNick Alcock2-8/+44
The deduplicating linker adds types from the linker inputs to the output via the same API everyone else does, so it's important that we can emit everything that the compiler wants us to. Unfortunately, the compiler may represent the unimplemented type (used for compiler constructs that CTF cannot currently encode) as type zero or as a type of kind CTF_K_UNKNOWN, and we don't allow the addition of types that cite the former. Adding this support adds a tiny bit of extra complexity: additions of structure members immediately following a member of the unimplemented type must be via ctf_add_member_offset or ctf_add_member_encoded, since we have no idea how big members of the unimplemented type are. (Attempts to do otherwise return -ECTF_NONREPRESENTABLE, like other attempts to do forbidden things with the unimplemented type.) Even slices of the unimplemented type are permitted: this is the only case in which you can slice a type that terminates in a non-integral type, on the grounds that it was likely integral in the source code, it's just that we can't represent that sort of integral type properly yet. libctf/ * ctf-create.c (ctf_add_reftype): Support refs to type zero. (ctf_add_array): Support array contents of type zero. (ctf_add_function): Support arguments and return types of type zero. (ctf_add_typedef): Support typedefs to type zero. (ctf_add_member_offset): Support members of type zero, unless added at unspecified (naturally-aligned) offset.
2020-07-22libctf: restructure error handling to reduce relocationsNick Alcock6-62/+100
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.
2020-07-22include, libctf: typo fixesNick Alcock2-1/+5
include/ * ctf-api.h: Fix typos in comments. libctf/ * ctf-impl.h: Fix typos in comments.
2020-07-22Fix problems in CTF handling code exposed by the Coverity static analysis tool.Nick Clifton2-13/+11
readelf * readelf.c (parse_args): Silence potential warnings about a memory resource leak when allocating space for ctf option values. (dump_section_as_ctf): Fix typo checking dump_ctf_strtab_name variable. libctf * ctf-archive.c (ctf_arc_write): Avoid calling close twice on the same file descriptor.
2020-07-04Add markers for binutils 2.35 branchNick Clifton1-0/+4
2020-06-26libctf: support platforms with separate libintlNick Alcock6-2/+112
We were not using the right configure machinery to spot libintl on platforms where it was required, leading to the spurious failure of various configure tests (e.g. for things like ELF support in BFD). libctf/ * aclocal.m4: Add config/gettext-sister.m4: Shuffle into alphabetical order. * configure.ac: Add ZW_GNU_GETTEXT_SISTER_DIR. * config.h.in: Regenerated. * Makefile.in: Likewise. * configure: Likewise.
2020-06-26libctf: add some missing #includes.Nick Alcock3-0/+7
Causes warnings on (at least) recent FreeBSD. libctf/ * ctf-create.c: Include <unistd.h>. * ctf-open-bfd.c: Likewise.
2020-06-26libctf, elfcpp, gold: do not assume that <byteswap.h> contains bswap_*Nick Alcock5-8/+68
At least one C library (uclibc-ng) defines some of these only when the compiler is GCC. We might as well test for all three cases and handle any of them being missing. Very similar code exists in libctf and split between elfcpp and gold: fix both. (Also sync up elfcpp with a change made to libctf swap.h a few months ago: since there is no out-of-line definition of the bswap replacements, they should be declared static inline, not just inline, to prevent the linker generating out-of-line references to them.) PR libctf/25120 libctf/ * configure.ac: Check for bswap_16, bswap_32, and bswap_64 decls. * swap.h (bswap_16): Do not assume that presence of <byteswap.h> means this is declared. (bswap_32): Likewise. (bswap_64): Likewise. (bswap_identity_64): Remove, unused. * configure: Regenerated. * config.h.in: Likewise. gold/ * configure.ac: Check for bswap_16, bswap_32, and bswap_64 decls. * configure: Regenerated. * config.h.in: Likewise. elfcpp/ * elfcpp_swap.h (bswap_16): Do not assume that presence of <byteswap.h> means this is declared. Make static inline, matching recent change to libctf, since there is no non-inline definition of these functions. (bswap_32): Likewise. (bswap_64): Likewise.
2020-06-26libctf: work with compilers not supporting GNU C attributesNick Alcock2-0/+15
The obvious fallback __attribute__ stanza was missing. Thanks to Harald van Dijk. PR 25120 libctf/ * ctf-impl.h (_libctf_printflike_): Add non-GNU-C fallback. (_libctf_unlikely_): Likewise. (_libctf_unused): Likewise. (_libctf_malloc_): Likewise.
2020-06-26libctf: avoid nonportable __thread in CTF archive handlingNick Alcock2-9/+15
This keeps archive searching threadsafe using the new bsearch_r that was just added to libiberty. PR25120 libctf/ * ctf-archive.c (search_nametbl): No longer global: declare... (ctf_arc_open_by_name_internal): ... here. Use bsearch_r. (search_modent_by_name): Take and use ARG for the nametbl.
2020-06-26libctf, binutils: support CTF archives like objdumpNick Alcock5-75/+88
objdump and readelf have one major CTF-related behavioural difference: objdump can read .ctf sections that contain CTF archives and extract and dump their members, while readelf cannot. Since the linker often emits CTF archives, this means that readelf intermittently and (from the user's perspective) randomly fails to read CTF in files that ld emits, with a confusing error message wrongly claiming that the CTF content is corrupt. This is purely because the archive-opening code in libctf was needlessly tangled up with the BFD code, so readelf couldn't use it. Here, we disentangle it, moving ctf_new_archive_internal from ctf-open-bfd.c into ctf-archive.c and merging it with the helper function in ctf-archive.c it was already using. We add a new public API function ctf_arc_bufopen, that looks very like ctf_bufopen but returns an archive given suitable section data rather than a ctf_file_t: the archive is a ctf_archive_t, so it can be called on raw CTF dictionaries (with no archive present) and will return a single-member synthetic "archive". There is a tiny lifetime tweak here: before now, the archive code could assume that the symbol section in the ctf_archive_internal wrapper structure was always owned by BFD if it was present and should always be freed: now, the caller can pass one in via ctf_arc_bufopen, wihch has the usual lifetime rules for such sections (caller frees): so we add an extra field to track whether this is an internal call from ctf-open-bfd, in which case we still free the symbol section. include/ * ctf-api.h (ctf_arc_bufopen): New. libctf/ * ctf-impl.h (ctf_new_archive_internal): Declare. (ctf_arc_bufopen): Remove. (ctf_archive_internal) <ctfi_free_symsect>: New. * ctf-archive.c (ctf_arc_close): Use it. (ctf_arc_bufopen): Fuse into... (ctf_new_archive_internal): ... this, moved across from... * ctf-open-bfd.c: ... here. (ctf_bfdopen_ctfsect): Use ctf_arc_bufopen. * libctf.ver: Add it. binutils/ * readelf.c (dump_section_as_ctf): Support .ctf archives using ctf_arc_bufopen. Automatically load the .ctf member of such archives as the parent of all other members, unless specifically overridden via --ctf-parent. Split out dumping code into... (dump_ctf_archive_member): ... here, as in objdump, and call it once per archive member. (dump_ctf_indent_lines): Code style fix.
2020-06-26libctf: create: forwards are always in the namespace of their referentNick Alcock2-2/+14
The C namespace a forward is located in is always the same as the namespace of the corresponding complete type: 'struct foo' is in the struct namespace and does not collide with, say, 'union foo'. libctf allowed for this in many places, but inconsistently: in particular, forward *addition* never allowed for this, and was interning forwards in the default namespace, which is always wrong, since you can only forward structs, unions and enums, all of which are in their own namespaces in C. Forward removal needs corresponding adjustment to remove the names form the right namespace, as does ctf_rollback. libctf/ * ctf-create.c (ctf_add_forward): Intern in the right namespace. (ctf_dtd_delete): Remove correspondingly. (ctf_rollback): Likewise.
2020-06-26libctf: create: ctf_add_type should hand back already-added non-SoUsNick Alcock2-6/+15
When we add a type from a dictionary and then try to add it again, we should hand it back unchanged unless it is a structure, union or enum with a different number of members. That's what the comment says we do. Instead, we hand it back unchanged *only* if it is a structure, union or enum with the same number of members: non-structs, unions and enums are unconditionally added. This causes extreme type bloating and (in conjunction with the bug fixed by the next commit) can easily lead to the same type being mistakenly added to a dictionary more than once (which, for forwards, was not banned and led to dictionary corruption). libctf/ * ctf-create.c (ctf_add_type_internal): Hand back existing types unchanged.
2020-06-26libctf: create: don't add forwards if the type added already existsNick Alcock2-1/+9
This is what ctf_add_forward is documented to do, but it's not what it actually does: the code is quite happy to add forwards that duplicate existing structs, etc. This is obviously wrong and breaks both the nondeduplicating linker and the upcoming deduplicator, as well as allowing ordinary callers of ctf_add_type to corrupt the dictionary by just adding the same root- visible forward more than once. libctf/ * ctf-create.c (ctf_add_forward): Don't add forwards to types that already exist.
2020-06-26libctf: create: non-root-visible types should not appear in name tablesNick Alcock4-17/+53
We were accidentally interning newly-added and newly-opened non-root-visible types into name tables, and removing names from name tables when such types were removed. This is very wrong: the whole point of non-root-visible types is they do not go in name tables and cannot be looked up by name. This bug made non-root-visible types basically identical to root-visible types, right back to the earliest days of libctf in the Solaris era. libctf/ * ctf-open.c (init_types): Only intern root-visible types. * ctf-create.c (ctf_dtd_insert): Likewise. (ctf_dtd_delete): Only remove root-visible types. (ctf_rollback): Likewise. (ctf_add_generic): Adjust. (ctf_add_struct_sized): Adjust comment. (ctf_add_union_sized): Likewise. (ctf_add_enum): Likewise. * ctf-impl.h (ctf_dtd_insert): Adjust prototype.
2020-03-11libctf: Mark bswap_identity_64 inline function as static.John Baldwin2-1/+5
This is similar to cbbbc402e059ee345cb781d3ceb757ae1cc679ee and fixes a link error with duplicately defined symbols on FreeBSD. libctf/ChangeLog: * swap.h (bswap_identity_64): Make static.
2020-01-18Add markers for 2.34 branch to the NEWS files and ChangeLogs.Nick Clifton1-0/+4
2020-01-05Fix libctf ChangeLog date in most recent entry.Joel Brobecker1-1/+1
2020-01-05libctf: Add configure check for asprintf (for MinGW)Eli Zaretskii4-2/+72
This commit fixes a compilation warning when compiling libctf on MinGW: libctf/ctf-dump.c:118:8: warning: implicit declaration of function 'asprintf'; did you mean 'vasprintf'? [-Wimplicit-function-declaration] if (asprintf (&bit, " %lx: [slice 0x%x:0x%x]", ^~~~~~~~ vasprintf MinGW doesn't provide that function, so we depend on the one provided by libiberty. However, the declaration is guarded by HAVE_DECL_ASPRINTF, which we do not have in libctf's config.h. libctf/ChangeLog: PR binutils/25155: * configure.ac: Add AC_CHECK_DECLS([asprintf]). * configure, config.h.in: Regenerate.
2020-01-01Re: Update year range in copyright notice of binutils filesAlan Modra1-0/+4
Add the ChangeLog entry.
2020-01-01Update year range in copyright notice of binutils filesAlan Modra26-29/+29
2019-10-16libctf: mark swap.h inline functions as staticSimon Marchi2-3/+7
When building binutils with mingw-w64, I get the following errors: make[4]: Entering directory '/home/simark/build/binutils-gdb-mingw/binutils' /bin/sh ./libtool --tag=CC --mode=link ccache x86_64-w64-mingw32-gcc -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Wstack-usage=262144 -Wno-format -Werror -I/home/simark/src/binutils-gdb/binutils/../zlib -g3 -O0 -D__USE_MINGW_ACCESS -Wl,--stack,12582912 -o objdump.exe objdump.o dwarf.o prdbg.o rddbg.o debug.o stabs.o rdcoff.o bucomm.o version.o filemode.o elfcomm.o ../opcodes/libopcodes.la ../libctf/libctf.la ../bfd/libbfd.la ../libiberty/libiberty.a -lintl libtool: link: ccache x86_64-w64-mingw32-gcc -W -Wall -Wstrict-prototypes -Wmissing-prototypes -Wshadow -Wstack-usage=262144 -Wno-format -Werror -I/home/simark/src/binutils-gdb/binutils/../zlib -g3 -O0 -D__USE_MINGW_ACCESS -Wl,--stack -Wl,12582912 -o .libs/objdump.exe objdump.o dwarf.o prdbg.o rddbg.o debug.o stabs.o rdcoff.o bucomm.o version.o filemode.o elfcomm.o ../opcodes/.libs/libopcodes.a ../libctf/.libs/libctf.a -L/home/simark/build/binutils-gdb-mingw/zlib ../bfd/.libs/libbfd.a -lz ../libiberty/libiberty.a -lintl /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open.o): in function `flip_header': /home/simark/src/binutils-gdb/libctf/ctf-open.c:964: undefined reference to `bswap_16' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:967: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:968: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:969: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:970: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:971: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open.o):/home/simark/src/binutils-gdb/libctf/ctf-open.c:972: more undefined references to `bswap_32' follow /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open.o): in function `flip_types': /home/simark/src/binutils-gdb/libctf/ctf-open.c:1112: undefined reference to `bswap_16' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1113: undefined reference to `bswap_16' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1132: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1133: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1134: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1135: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: /home/simark/src/binutils-gdb/libctf/ctf-open.c:1144: undefined reference to `bswap_32' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open.o):/home/simark/src/binutils-gdb/libctf/ctf-open.c:1145: more undefined references to `bswap_32' follow /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open.o): in function `ctf_bufopen_internal': /home/simark/src/binutils-gdb/libctf/ctf-open.c:1342: undefined reference to `bswap_16' /usr/lib/gcc/x86_64-w64-mingw32/9.2.0/../../../../x86_64-w64-mingw32/bin/ld: ../libctf/.libs/libctf.a(ctf-open-bfd.o): in function `ctf_fdopen': /home/simark/src/binutils-gdb/libctf/ctf-open-bfd.c:268: undefined reference to `bswap_16' Apparently [1], if we have a function with `inline` but not `static`, there should be a compilation unit defining the symbol too. Alternatively, making those functions `static` fixes that. [1] https://stackoverflow.com/questions/16245521/c99-inline-function-in-c-file/16254679#16254679 libctf/ChangeLog: * swap.h (bswap_16, bswap_32, bswap_64): Make static. Change-Id: I8fd12aedf6c90f9b7418af948e5e0bae0c32eead
2019-10-03libctf: fix tabdamageNick Alcock3-3/+8
A little tabdamage predating the linker patch series has crept in. New in v5. libctf/ * ctf-open.c (ctf_bufopen_internal): Fix tabdamage. * ctf-types.c (ctf_type_lname): Likewise.
2019-10-03libctf: fix refcount leak in ctf_importNick Alcock2-0/+7
Calling ctf_import (fp, NULL) to cancel out a pre-existing import leaked the refcnt increment on the parent, so it could never be freed. New in v4. libctf/ * ctf-open.c (ctf_import): Do not leak a ctf_file_t ref on every ctf_import after the first for a given file.
2019-10-03libctf: make ctf_dump not crash on OOMNick Alcock4-23/+61
ctf_dump calls ctf_str_append extensively but never checks to see if it returns NULL (on OOM). If it ever does, we truncate the string we are appending to and leak it! Instead, create a variant of ctf_str_append that returns the *original string* on OOM, and use it in ctf-dump. It is far better to omit a tiny piece of a dump on OOM than to omit a bigger piece, and it is also better to do this in what is after all purely debugging code than it is to uglify ctf-dump.c with huge numbers of checks for the out-of-memory case. Slightly truncated debugging output is better than no debugging output at all and an out-of-memory message. New in v4. libctf/ * ctf-impl.h (ctf_str_append_noerr): Declare. * ctf-util.c (ctf_str_append_noerr): Define in terms of ctf_str_append. * ctf-dump.c (str_append): New, call it. (ctf_dump_format_type): Use str_append, not ctf_str_append. (ctf_dump_label): Likewise. (ctf_dump_objts): Likewise. (ctf_dump_funcs): Likewise. (ctf_dump_var): Likewise. (ctf_dump_member): Likewise. (ctf_dump_type): Likewise. (ctf_dump): Likewise.
2019-10-03libctf: remove ctf_malloc, ctf_free and ctf_strdupNick Alcock9-117/+156
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.
2019-10-03libctf: get the encoding of non-ints/fps in the dynamic space rightNick Alcock2-1/+26
If you call ctf_type_encoding() on a slice, you are meant to get the encoding of the slice with the format of the underlying type. If you call it on a non-int, non-fp, non-slice, you're meant to get the error ECTF_INTNOTFP. None of this was implemented for types in the dynamic space (which, now, is *all* types in writable containers). Instead, we were always returning the encoding as if it were a float, which for all other types consulted the wrong part of a discriminated union and returned garbage. (Curiously, existing users were more disturbed by the lack of an error in the non-int/fp/slice case than they were about getting garbage back.) libctf/ * ctf-types.c (ctf_type_encoding): Fix the dynamic case to work right for non-int/fps.
2019-10-03libctf: allow ctf_type_lname of a null pointer.Nick Alcock2-1/+7
The code was meant to handle this, but accidentally dereferenced the null pointer before checking it for nullity. v5: fix tabdamage. libctf/ * ctf-types.c (ctf_type_name): Don't strlen a potentially- null pointer.
2019-10-03libctf: properly handle ctf_add_type of forwards and self-reffing structsNick Alcock4-85/+134
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.
2019-10-03libctf: avoid the need to ever use ctf_updateNick Alcock10-422/+896
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.
2019-10-03libctf: handle nonrepresentable types at link timeNick Alcock6-27/+130
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.
2019-10-03libctf: installable libctf as a shared libraryNick Alcock8-82/+8150
This lets other programs read and write CTF-format data. Two versioned shared libraries are created: libctf.so and libctf-nobfd.so. They contain identical content except that libctf-nobfd.so contains no references to libbfd and does not implement ctf_open, ctf_fdopen, ctf_bfdopen or ctf_bfdopen_ctfsect, so it can be used by programs that cannot use BFD, like readelf. The soname major version is presently .0 until the linker API stabilizes, when it will flip to .1 and hopefully never change again. New in v3. v4: libtoolize and turn into a pair of shared libraries. Drop --enable-install-ctf: now controlled by --enable-shared and --enable-install-libbfd, like everything else. v5: Add ../bfd to ACLOCAL_AMFLAGS and AC_CONFIG_MACRO_DIR. Fix tabdamage. * Makefile.def (host_modules): libctf is no longer no_install. * Makefile.in: Regenerated. libctf/ * configure.ac (AC_DISABLE_SHARED): New, like opcodes/. (LT_INIT): Likewise. (AM_INSTALL_LIBBFD): Likewise. (dlopen): Note why this is necessary in a comment. (SHARED_LIBADD): Initialize for possibly-PIC libiberty: derived from opcodes/. (SHARED_LDFLAGS): Likewise. (BFD_LIBADD): Likewise, for libbfd. (BFD_DEPENDENCIES): Likewise. (VERSION_FLAGS): Initialize, using a version script if ld supports one, or libtool -export-symbols-regex otherwise. (AC_CONFIG_MACRO_DIR): Add ../BFD. * Makefile.am (ACLOCAL_AMFLAGS): Likewise. (INCDIR): New. (AM_CPPFLAGS): Use $(srcdir), not $(top_srcdir). (noinst_LIBRARIES): Replace with... [INSTALL_LIBBFD] (lib_LTLIBRARIES): This, or... [!INSTALL_LIBBFD] (noinst_LTLIBRARIES): ... this, mentioning new libctf-nobfd.la as well. [INSTALL_LIBCTF] (include_HEADERS): Add the CTF headers. [!INSTALL_LIBCTF] (include_HEADERS): New, empty. (libctf_a_SOURCES): Rename to... (libctf_nobfd_la_SOURCES): ... this, all of libctf other than ctf-open-bfd.c. (libctf_la_SOURCES): Now derived from libctf_nobfd_la_SOURCES, with ctf-open-bfd.c added. (libctf_nobfd_la_LIBADD): New, using @SHARED_LIBADD@. (libctf_la_LIBADD): New, using @BFD_LIBADD@ as well. (libctf_la_DEPENDENCIES): New, using @BFD_DEPENDENCIES@. * Makefile.am [INSTALL_LIBCTF]: Use it. * aclocal.m4: Add ../bfd/acinclude.m4, ../config/acx.m4, and the libtool macros. * libctf.ver: New, everything is version LIBCTF_1.0 currently (even the unstable components). * Makefile.in: Regenerated. * config.h.in: Likewise. * configure: Likewise. binutils/ * Makefile.am (LIBCTF): Mention the .la file. (LIBCTF_NOBFD): New. (readelf_DEPENDENCIES): Use it. (readelf_LDADD): Likewise. * Makefile.in: Regenerated. ld/ * configure.ac (TESTCTFLIB): Set to the .so or .a, like TESTBFDLIB. * Makefile.am (TESTCTFLIB): Use it. (LIBCTF): Use the .la file. (check-DEJAGNU): Use it. * Makefile.in: Regenerated. * configure: Likewise. include/ * ctf-api.h: Note the instability of the ctf_link interfaces.
2019-10-03libctf: actually close bfds we have openedNick Alcock3-1/+8
When we do a ctf_fdopen, we open things via bfd_fdopenr and set up a hook to close the bfd again... but then we never actually call that hook from anywhere, so we eventually leak every bfd we open. Fix this by calling the hook (if set) in ctf_arc_close. New in v3. libctf/ * ctf-archive.c (ctf_arc_close): Call ctfi_bfd_close if set. * ctf-open-bfd.c (ctf_bfdclose): Fix comment.
2019-10-03libctf: bfd-open: mark the bfd as cacheableNick Alcock2-0/+5
Without this, the FD is only closed when the CTF file is, leading to running out of fds on (e.g.) very large links. New in v3. libctf/ * ctf-open-bfd.c (ctf_fdopen): Call bfd_set_cacheable.
2019-10-03libctf: get rid of a disruptive public include of <sys/param.h>Nick Alcock2-0/+5
This hoary old header defines things like MAX that users of libctf might perfectly reasonably define themselves. The CTF headers do not need it: move it into libctf/ctf-impl.h instead. include/ * ctf-api.h (includes): No longer include <sys/param.h>. libctf/ * ctf-impl.h (includes): Include <sys/param.h> here.
2019-10-03libctf: eschew C99 for loop initial declarationsNick Alcock2-7/+21
We shouldn't use these, since binutils doesn't require a C99-capable compiler yet. New in v3. v5: fix tabdamage. libctf/ * ctf-open.c (flip_lbls): Eschew for-loop initial declarations. (flip_objts): Likewise. (flip_vars): Likewise. (flip_types): Likewise.
2019-10-03libctf: don't leak hash keys or values on value replacementNick Alcock2-4/+22
When a ctf_dynhash_insert() finds a slot already existing, it should call the key and value free functions on the existing key and value and move the passed-in key into place, so that the lifetime rules for hash keys are always the same no matter whether the key existed or not but neither are the keys or values leaked. New in v3. v5: fix tabdamage. libctf/ * ctf-hash.c (ctf_hashtab_insert): Pass in the key and value freeing functions: if set, free the key and value if the slot already exists. Always reassign the key. (ctf_dynhash_insert): Adjust call appropriately. (ctf_hash_insert_type): Likewise.
2019-10-03libctf: teach ctf_add_type how forwards workNick Alcock2-14/+35
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.
2019-10-03libctf: add CU-mapping machineryNick Alcock5-4/+194
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.
2019-10-03libctf: add linking of the variable sectionNick Alcock3-25/+145
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.
2019-10-03libctf: map from old to corresponding newly-added types in ctf_add_typeNick Alcock6-4/+202
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.
2019-10-03libctf: add the ctf_link machineryNick Alcock8-14/+564
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.
2019-10-03libctf: dump: check the right error values when dumping functionsNick Alcock2-1/+6
We weren't correctly detecting when there were no functions to dump in the function info table, because we were checking for ECTF_NOTYPEDAT, which means there are no *data objects* to dump. Adjust accordingly. libctf/ * ctf-dump.c (ctf_dump_funcs): Check the right error value.
2019-10-03libctf: dump: support non-root type dumpingNick Alcock2-12/+36
Use the recently-added ctf_type_iter_all function to iterate over non-root types, too, indicating them via {....} surrounding the type description in the dump. libctf/ * ctf-dump.c (ctf_dump): Use ctf_type_iter_all to dump types, not ctf_type_iter. (ctf_dump_type): Pass down the flag from ctf_type_iter_all. (ctf_dump_format_type): Add non-root-type { } notation. Add root flag to prototype. (ctf_dump_label): Adjust accordingly. (ctf_dump_objts): Likewise. (ctf_dump_var): Likewise.
2019-10-03libctf: fix double-free on ctf_compress_write error pathNick Alcock2-1/+4
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.