binutils-gdb/libctf/swap.h

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libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
/* Interface to byteswapping functions.
Copyright (C) 2006-2023 Free Software Foundation, Inc.
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
This file is part of libctf.
libctf is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not see
<http://www.gnu.org/licenses/>. */
#ifndef _CTF_SWAP_H
#define _CTF_SWAP_H
#include "config.h"
#include <stdint.h>
libctf, include: support foreign-endianness symtabs with CTF The CTF symbol lookup machinery added recently has one deficit: it assumes the symtab is in the machine's native endianness. This is always true when the linker is writing out symtabs (because cross linkers byteswap symbols only after libctf has been called on them), but may be untrue in the cross case when the linker or another tool (objdump, etc) is reading them. Unfortunately the easy way to model this to the caller, as an endianness field in the ctf_sect_t, is precluded because doing so would change the size of the ctf_sect_t, which would be an ABI break. So, instead, allow the endianness of the symtab to be set after open time, by calling one of the two new API functions ctf_symsect_endianness (for ctf_dict_t's) or ctf_arc_symsect_endianness (for entire ctf_archive_t's). libctf calls these functions automatically for objects opened via any of the BFD-aware mechanisms (ctf_bfdopen, ctf_bfdopen_ctfsect, ctf_fdopen, ctf_open, or ctf_arc_open), but the various mechanisms that just take raw ctf_sect_t's will assume the symtab is in native endianness and need a later call to ctf_*symsect_endianness to adjust it if needed. (This call is basically free if the endianness is actually native: it only costs anything if the symtab endianness was previously guessed wrong, and there is a symtab, and we are using it directly rather than using symtab indexing.) Obviously, calling ctf_lookup_by_symbol or ctf_symbol_next before the symtab endianness is correctly set will probably give wrong answers -- but you can set it at any time as long as it is before then. include/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h: Style nit: remove () on function names in comments. (ctf_sect_t): Mention endianness concerns. (ctf_symsect_endianness): New declaration. (ctf_arc_symsect_endianness): Likewise. libctf/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dict_t) <ctf_symtab_little_endian>: New. (struct ctf_archive_internal) <ctfi_symsect_little_endian>: Likewise. * ctf-create.c (ctf_serialize): Adjust for new field. * ctf-open.c (init_symtab): Note the semantics of repeated calls. (ctf_symsect_endianness): New. (ctf_bufopen_internal): Set ctf_symtab_little_endian suitably for the native endianness. (_Static_assert): Moved... (swap_thing): ... with this... * swap.h: ... to here. * ctf-util.c (ctf_elf32_to_link_sym): Use it, byteswapping the Elf32_Sym if the ctf_symtab_little_endian demands it. (ctf_elf64_to_link_sym): Likewise swap the Elf64_Sym if needed. * ctf-archive.c (ctf_arc_symsect_endianness): New, set the endianness of the symtab used by the dicts in an archive. (ctf_archive_iter_internal): Initialize to unknown (assumed native, do not call ctf_symsect_endianness). (ctf_dict_open_by_offset): Call ctf_symsect_endianness if need be. (ctf_dict_open_internal): Propagate the endianness down. (ctf_dict_open_sections): Likewise. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Get the endianness from the struct bfd and pass it down to the archive. * libctf.ver: Add ctf_symsect_endianness and ctf_arc_symsect_endianness.
2020-11-24 05:17:44 +08:00
#include <assert.h>
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
#ifdef HAVE_BYTESWAP_H
#include <byteswap.h>
#endif /* defined(HAVE_BYTESWAP_H) */
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
/* Provide our own versions of the byteswap functions. */
#if !HAVE_DECL_BSWAP_16
libctf: mark swap.h inline functions as static 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
2019-10-16 23:11:28 +08:00
static inline uint16_t
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.
2019-05-31 17:10:51 +08:00
bswap_16 (uint16_t v)
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
{
return ((v >> 8) & 0xff) | ((v & 0xff) << 8);
}
#endif /* !HAVE_DECL_BSWAP16 */
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
#if !HAVE_DECL_BSWAP_32
libctf: mark swap.h inline functions as static 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
2019-10-16 23:11:28 +08:00
static inline uint32_t
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.
2019-05-31 17:10:51 +08:00
bswap_32 (uint32_t v)
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
{
return ( ((v & 0xff000000) >> 24)
| ((v & 0x00ff0000) >> 8)
| ((v & 0x0000ff00) << 8)
| ((v & 0x000000ff) << 24));
}
#endif /* !HAVE_DECL_BSWAP32 */
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
#if !HAVE_DECL_BSWAP_64
libctf: mark swap.h inline functions as static 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
2019-10-16 23:11:28 +08:00
static inline uint64_t
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.
2019-05-31 17:10:51 +08:00
bswap_64 (uint64_t v)
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
{
return ( ((v & 0xff00000000000000ULL) >> 56)
| ((v & 0x00ff000000000000ULL) >> 40)
| ((v & 0x0000ff0000000000ULL) >> 24)
| ((v & 0x000000ff00000000ULL) >> 8)
| ((v & 0x00000000ff000000ULL) << 8)
| ((v & 0x0000000000ff0000ULL) << 24)
| ((v & 0x000000000000ff00ULL) << 40)
| ((v & 0x00000000000000ffULL) << 56));
}
#endif /* !HAVE_DECL_BSWAP64 */
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
libctf, include: support foreign-endianness symtabs with CTF The CTF symbol lookup machinery added recently has one deficit: it assumes the symtab is in the machine's native endianness. This is always true when the linker is writing out symtabs (because cross linkers byteswap symbols only after libctf has been called on them), but may be untrue in the cross case when the linker or another tool (objdump, etc) is reading them. Unfortunately the easy way to model this to the caller, as an endianness field in the ctf_sect_t, is precluded because doing so would change the size of the ctf_sect_t, which would be an ABI break. So, instead, allow the endianness of the symtab to be set after open time, by calling one of the two new API functions ctf_symsect_endianness (for ctf_dict_t's) or ctf_arc_symsect_endianness (for entire ctf_archive_t's). libctf calls these functions automatically for objects opened via any of the BFD-aware mechanisms (ctf_bfdopen, ctf_bfdopen_ctfsect, ctf_fdopen, ctf_open, or ctf_arc_open), but the various mechanisms that just take raw ctf_sect_t's will assume the symtab is in native endianness and need a later call to ctf_*symsect_endianness to adjust it if needed. (This call is basically free if the endianness is actually native: it only costs anything if the symtab endianness was previously guessed wrong, and there is a symtab, and we are using it directly rather than using symtab indexing.) Obviously, calling ctf_lookup_by_symbol or ctf_symbol_next before the symtab endianness is correctly set will probably give wrong answers -- but you can set it at any time as long as it is before then. include/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h: Style nit: remove () on function names in comments. (ctf_sect_t): Mention endianness concerns. (ctf_symsect_endianness): New declaration. (ctf_arc_symsect_endianness): Likewise. libctf/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dict_t) <ctf_symtab_little_endian>: New. (struct ctf_archive_internal) <ctfi_symsect_little_endian>: Likewise. * ctf-create.c (ctf_serialize): Adjust for new field. * ctf-open.c (init_symtab): Note the semantics of repeated calls. (ctf_symsect_endianness): New. (ctf_bufopen_internal): Set ctf_symtab_little_endian suitably for the native endianness. (_Static_assert): Moved... (swap_thing): ... with this... * swap.h: ... to here. * ctf-util.c (ctf_elf32_to_link_sym): Use it, byteswapping the Elf32_Sym if the ctf_symtab_little_endian demands it. (ctf_elf64_to_link_sym): Likewise swap the Elf64_Sym if needed. * ctf-archive.c (ctf_arc_symsect_endianness): New, set the endianness of the symtab used by the dicts in an archive. (ctf_archive_iter_internal): Initialize to unknown (assumed native, do not call ctf_symsect_endianness). (ctf_dict_open_by_offset): Call ctf_symsect_endianness if need be. (ctf_dict_open_internal): Propagate the endianness down. (ctf_dict_open_sections): Likewise. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Get the endianness from the struct bfd and pass it down to the archive. * libctf.ver: Add ctf_symsect_endianness and ctf_arc_symsect_endianness.
2020-11-24 05:17:44 +08:00
/* < C11? define away static assertions. */
#if !defined (__STDC_VERSION__) || __STDC_VERSION__ < 201112L
#define _Static_assert(cond, err)
#endif
/* Swap the endianness of something. */
#define swap_thing(x) \
do \
{ \
_Static_assert (sizeof (x) == 1 || (sizeof (x) % 2 == 0 \
&& sizeof (x) <= 8), \
"Invalid size, update endianness code"); \
switch (sizeof (x)) { \
case 2: x = bswap_16 (x); break; \
case 4: x = bswap_32 (x); break; \
case 8: x = bswap_64 (x); break; \
case 1: /* Nothing needs doing */ \
break; \
} \
libctf, include: support foreign-endianness symtabs with CTF The CTF symbol lookup machinery added recently has one deficit: it assumes the symtab is in the machine's native endianness. This is always true when the linker is writing out symtabs (because cross linkers byteswap symbols only after libctf has been called on them), but may be untrue in the cross case when the linker or another tool (objdump, etc) is reading them. Unfortunately the easy way to model this to the caller, as an endianness field in the ctf_sect_t, is precluded because doing so would change the size of the ctf_sect_t, which would be an ABI break. So, instead, allow the endianness of the symtab to be set after open time, by calling one of the two new API functions ctf_symsect_endianness (for ctf_dict_t's) or ctf_arc_symsect_endianness (for entire ctf_archive_t's). libctf calls these functions automatically for objects opened via any of the BFD-aware mechanisms (ctf_bfdopen, ctf_bfdopen_ctfsect, ctf_fdopen, ctf_open, or ctf_arc_open), but the various mechanisms that just take raw ctf_sect_t's will assume the symtab is in native endianness and need a later call to ctf_*symsect_endianness to adjust it if needed. (This call is basically free if the endianness is actually native: it only costs anything if the symtab endianness was previously guessed wrong, and there is a symtab, and we are using it directly rather than using symtab indexing.) Obviously, calling ctf_lookup_by_symbol or ctf_symbol_next before the symtab endianness is correctly set will probably give wrong answers -- but you can set it at any time as long as it is before then. include/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h: Style nit: remove () on function names in comments. (ctf_sect_t): Mention endianness concerns. (ctf_symsect_endianness): New declaration. (ctf_arc_symsect_endianness): Likewise. libctf/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dict_t) <ctf_symtab_little_endian>: New. (struct ctf_archive_internal) <ctfi_symsect_little_endian>: Likewise. * ctf-create.c (ctf_serialize): Adjust for new field. * ctf-open.c (init_symtab): Note the semantics of repeated calls. (ctf_symsect_endianness): New. (ctf_bufopen_internal): Set ctf_symtab_little_endian suitably for the native endianness. (_Static_assert): Moved... (swap_thing): ... with this... * swap.h: ... to here. * ctf-util.c (ctf_elf32_to_link_sym): Use it, byteswapping the Elf32_Sym if the ctf_symtab_little_endian demands it. (ctf_elf64_to_link_sym): Likewise swap the Elf64_Sym if needed. * ctf-archive.c (ctf_arc_symsect_endianness): New, set the endianness of the symtab used by the dicts in an archive. (ctf_archive_iter_internal): Initialize to unknown (assumed native, do not call ctf_symsect_endianness). (ctf_dict_open_by_offset): Call ctf_symsect_endianness if need be. (ctf_dict_open_internal): Propagate the endianness down. (ctf_dict_open_sections): Likewise. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Get the endianness from the struct bfd and pass it down to the archive. * libctf.ver: Add ctf_symsect_endianness and ctf_arc_symsect_endianness.
2020-11-24 05:17:44 +08:00
} \
while (0);
libctf, include: support foreign-endianness symtabs with CTF The CTF symbol lookup machinery added recently has one deficit: it assumes the symtab is in the machine's native endianness. This is always true when the linker is writing out symtabs (because cross linkers byteswap symbols only after libctf has been called on them), but may be untrue in the cross case when the linker or another tool (objdump, etc) is reading them. Unfortunately the easy way to model this to the caller, as an endianness field in the ctf_sect_t, is precluded because doing so would change the size of the ctf_sect_t, which would be an ABI break. So, instead, allow the endianness of the symtab to be set after open time, by calling one of the two new API functions ctf_symsect_endianness (for ctf_dict_t's) or ctf_arc_symsect_endianness (for entire ctf_archive_t's). libctf calls these functions automatically for objects opened via any of the BFD-aware mechanisms (ctf_bfdopen, ctf_bfdopen_ctfsect, ctf_fdopen, ctf_open, or ctf_arc_open), but the various mechanisms that just take raw ctf_sect_t's will assume the symtab is in native endianness and need a later call to ctf_*symsect_endianness to adjust it if needed. (This call is basically free if the endianness is actually native: it only costs anything if the symtab endianness was previously guessed wrong, and there is a symtab, and we are using it directly rather than using symtab indexing.) Obviously, calling ctf_lookup_by_symbol or ctf_symbol_next before the symtab endianness is correctly set will probably give wrong answers -- but you can set it at any time as long as it is before then. include/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-api.h: Style nit: remove () on function names in comments. (ctf_sect_t): Mention endianness concerns. (ctf_symsect_endianness): New declaration. (ctf_arc_symsect_endianness): Likewise. libctf/ChangeLog 2020-11-23 Nick Alcock <nick.alcock@oracle.com> * ctf-impl.h (ctf_dict_t) <ctf_symtab_little_endian>: New. (struct ctf_archive_internal) <ctfi_symsect_little_endian>: Likewise. * ctf-create.c (ctf_serialize): Adjust for new field. * ctf-open.c (init_symtab): Note the semantics of repeated calls. (ctf_symsect_endianness): New. (ctf_bufopen_internal): Set ctf_symtab_little_endian suitably for the native endianness. (_Static_assert): Moved... (swap_thing): ... with this... * swap.h: ... to here. * ctf-util.c (ctf_elf32_to_link_sym): Use it, byteswapping the Elf32_Sym if the ctf_symtab_little_endian demands it. (ctf_elf64_to_link_sym): Likewise swap the Elf64_Sym if needed. * ctf-archive.c (ctf_arc_symsect_endianness): New, set the endianness of the symtab used by the dicts in an archive. (ctf_archive_iter_internal): Initialize to unknown (assumed native, do not call ctf_symsect_endianness). (ctf_dict_open_by_offset): Call ctf_symsect_endianness if need be. (ctf_dict_open_internal): Propagate the endianness down. (ctf_dict_open_sections): Likewise. * ctf-open-bfd.c (ctf_bfdopen_ctfsect): Get the endianness from the struct bfd and pass it down to the archive. * libctf.ver: Add ctf_symsect_endianness and ctf_arc_symsect_endianness.
2020-11-24 05:17:44 +08:00
libctf: opening This fills in the other half of the opening/creation puzzle: opening of already-existing CTF files. Such files are always read-only: if you want to add to a CTF file opened with one of the opening functions in this file, use ctf_add_type(), in a later commit, to copy appropriate types into a newly ctf_create()d, writable container. The lowest-level opening functions are in here: ctf_bufopen(), which takes ctf_sect_t structures akin to ELF section headers, and ctf_simple_open(), which can be used if you don't have an entire ELF section header to work from. Both will malloc() new space for the buffers only if necessary, will mmap() directly from the file if requested, and will mprotect() it afterwards to prevent accidental corruption of the types. These functions are also used by ctf_update() when converting types in a writable container into read-only types that can be looked up using the lookup functions (in later commits). The files are always of the native endianness of the system that created them: at read time, the endianness of the header magic number is used to determine whether or not the file needs byte-swapping, and the entire thing is aggressively byte-swapped. The agggressive nature of this swapping avoids complicating the rest of the code with endianness conversions, while the native endianness introduces no byte-swapping overhead in the common case. (The endianness-independence code is also much newer than everything else in this file, and deserves closer scrutiny.) The accessors at the top of the file are there to transparently support older versions of the CTF file format, allowing translation from older formats that have different sizes for the structures in ctf.h: currently, these older formats are intermingled with the newer ones in ctf.h: they will probably migrate to a compatibility header in time, to ease readability. The ctf_set_base() function is split out for the same reason: when conversion code to a newer format is written, it would need to malloc() new storage for the entire ctf_file_t if a file format change causes it to grow, and for that we need ctf_set_base() to be a separate function. One pair of linked data structures supported by this file has no creation code in libctf yet: the data and function object sections read by init_symtab(). These will probably arrive soon, when the linker comes to need them. (init_symtab() has hardly been changed since 2009, but if any code in libctf has rotted over time, this will.) A few simple accessors are also present that can even be called on read-only containers because they don't actually modify them, since the relevant things are not stored in the container but merely change its operation: ctf_setmodel(), which lets you specify whether a container is LP64 or not (used to statically determine the sizes of a few types), ctf_import(), which is the only way to associate a parent container with a child container, and ctf_setspecific(), which lets the caller associate an arbitrary pointer with the CTF container for any use. If the user doesn't call these functions correctly, libctf will misbehave: this is particularly important for ctf_import(), since a container built against a given parent container will not be able to resolve types that depend on types in the parent unless it is ctf_import()ed with a parent container with the same set of types at the same IDs, or a superset. Possible future extensions (also noted in the ctf-hash.c file) include storing a count of things so that we don't need to do one pass over the CTF file counting everything, and computing a perfect hash at CTF creation time in some compact form, storing it in the CTF file, and using it to hash things so we don't need to do a second pass over the entire CTF file to set up the hashes used to go from names to type IDs. (There are multiple such hashes, one for each C type namespace: types, enums, structs, and unions.) libctf/ * ctf-open.c: New file. * swap.h: Likewise. include/ * ctf-api.h (ctf_file_close): New declaration. (ctf_getdatasect): Likewise. (ctf_parent_file): Likewise. (ctf_parent_name): Likewise. (ctf_parent_name_set): Likewise. (ctf_import): Likewise. (ctf_setmodel): Likewise. (ctf_getmodel): Likewise. (ctf_setspecific): Likewise. (ctf_getspecific): Likewise.
2019-04-24 17:17:13 +08:00
#endif /* !defined(_CTF_SWAP_H) */