From 288f6b199a8b1a60d4fb1f54ca7b883cdd5afca2 Mon Sep 17 00:00:00 2001 From: Aaron Merey Date: Mon, 28 Oct 2019 13:29:26 -0400 Subject: debuginfod 1/2: client side Introduce the debuginfod/ subdirectory, containing the client for a new debuginfo-over-http service, in shared-library and command-line forms. Two functions in libdwfl make calls into the client library to fetch elf/dwarf files by buildid, as a fallback. Instead of normal dynamic linking (thus pulling in a variety of curl dependencies), the libdwfl hooks use dlopen/dlsym. Server & tests coming in patch 2. Signed-off-by: Aaron Merey Signed-off-by: Frank Ch. Eigler --- ChangeLog | 6 + Makefile.am | 4 + config/Makefile.am | 4 +- config/libdebuginfod.pc.in | 12 + configure.ac | 23 +- debuginfod/ChangeLog | 9 + debuginfod/Makefile.am | 114 +++++++ debuginfod/debuginfod-client.c | 665 +++++++++++++++++++++++++++++++++++++++ debuginfod/debuginfod-find.c | 101 ++++++ debuginfod/debuginfod.h | 69 ++++ debuginfod/libdebuginfod.map | 7 + doc/Makefile.am | 10 +- doc/debuginfod-find.1 | 137 ++++++++ doc/debuginfod_find_debuginfo.3 | 182 +++++++++++ doc/debuginfod_find_executable.3 | 1 + doc/debuginfod_find_source.3 | 1 + libdw/ChangeLog | 4 + libdw/Makefile.am | 2 +- libdwfl/ChangeLog | 6 + libdwfl/Makefile.am | 3 +- libdwfl/dwfl_build_id_find_elf.c | 32 +- libdwfl/find-debuginfo.c | 31 +- m4/ChangeLog | 4 + m4/Makefile.am | 2 +- m4/ax_check_compile_flag.m4 | 74 +++++ m4/ax_cxx_compile_stdcxx.m4 | 556 ++++++++++++++++++++++++++++++++ 26 files changed, 2048 insertions(+), 11 deletions(-) create mode 100644 config/libdebuginfod.pc.in create mode 100644 debuginfod/ChangeLog create mode 100644 debuginfod/Makefile.am create mode 100644 debuginfod/debuginfod-client.c create mode 100644 debuginfod/debuginfod-find.c create mode 100644 debuginfod/debuginfod.h create mode 100644 debuginfod/libdebuginfod.map create mode 100644 doc/debuginfod-find.1 create mode 100644 doc/debuginfod_find_debuginfo.3 create mode 100644 doc/debuginfod_find_executable.3 create mode 100644 doc/debuginfod_find_source.3 create mode 100644 m4/ax_check_compile_flag.m4 create mode 100644 m4/ax_cxx_compile_stdcxx.m4 diff --git a/ChangeLog b/ChangeLog index 433a5f3c..9d1c05f4 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2019-10-28 Aaron Merey + + * debuginfod/: New directory for debuginfod code. + * Makefile.am (SUBDIRS): Recurse there. + * configure.ac (--enable-debuginfod): New flag & checks. + 2019-08-25 Jonathon Anderson * configure.ac: Add new --enable-valgrind-annotations diff --git a/Makefile.am b/Makefile.am index 52f64fc9..bd8926b5 100644 --- a/Makefile.am +++ b/Makefile.am @@ -29,6 +29,10 @@ pkginclude_HEADERS = version.h SUBDIRS = config m4 lib libelf libcpu backends libebl libdwelf libdwfl libdw \ libasm src po doc tests +if DEBUGINFOD +SUBDIRS += debuginfod +endif + EXTRA_DIST = elfutils.spec GPG-KEY NOTES CONTRIBUTING \ COPYING COPYING-GPLV2 COPYING-LGPLV3 diff --git a/config/Makefile.am b/config/Makefile.am index 9d292cee..10bd8d31 100644 --- a/config/Makefile.am +++ b/config/Makefile.am @@ -29,10 +29,10 @@ ## not, see . ## EXTRA_DIST = elfutils.spec.in known-dwarf.awk 10-default-yama-scope.conf - libelf.pc.in libdw.pc.in + libelf.pc.in libdw.pc.in libdebuginfod.pc.in pkgconfigdir = $(libdir)/pkgconfig -pkgconfig_DATA = libelf.pc libdw.pc +pkgconfig_DATA = libelf.pc libdw.pc libdebuginfod.pc if MAINTAINER_MODE $(srcdir)/elfutils.spec.in: $(top_srcdir)/NEWS diff --git a/config/libdebuginfod.pc.in b/config/libdebuginfod.pc.in new file mode 100644 index 00000000..46722a76 --- /dev/null +++ b/config/libdebuginfod.pc.in @@ -0,0 +1,12 @@ +prefix=@prefix@ +exec_prefix=@exec_prefix@ +libdir=@libdir@ +includedir=@includedir@ + +Name: debuginfod +Description: elfutils library to query debuginfo files from debuginfod servers +Version: @VERSION@ +URL: http://elfutils.org/ + +Libs: -L${libdir} -ldebuginfod +Cflags: -I${includedir} diff --git a/configure.ac b/configure.ac index 7fc3acb6..8a3ed3af 100644 --- a/configure.ac +++ b/configure.ac @@ -60,6 +60,8 @@ AC_CONFIG_FILES([m4/Makefile]) dnl The RPM spec file. We substitute a few values in the file. AC_CONFIG_FILES([elfutils.spec:config/elfutils.spec.in]) +dnl debuginfo-server client & server parts. +AC_CONFIG_FILES([debuginfod/Makefile]) AC_CANONICAL_HOST @@ -86,6 +88,8 @@ AS_IF([test "$use_locks" = yes], AH_TEMPLATE([USE_LOCKS], [Defined if libraries should be thread-safe.]) AC_PROG_CC +AC_PROG_CXX +AX_CXX_COMPILE_STDCXX(11, noext, optional) AC_PROG_RANLIB AC_PROG_YACC AM_PROG_LEX @@ -567,7 +571,7 @@ AM_CONDITIONAL(STANDALONE, false)dnl Used in tests/Makefile.am, which see. AC_CONFIG_FILES([tests/Makefile]) dnl pkgconfig files -AC_CONFIG_FILES([config/libelf.pc config/libdw.pc]) +AC_CONFIG_FILES([config/libelf.pc config/libdw.pc config/libdebuginfod.pc]) # Get the definitions necessary to create the Makefiles in the po # subdirectories. This is a small subset of the gettext rules. @@ -670,6 +674,22 @@ if test "$HAVE_BUNZIP2" = "no"; then AC_MSG_WARN([No bunzip2, needed to run make check]) fi +# Look for libmicrohttpd, libcurl, libarchive, sqlite for debuginfo server +# minimum versions as per rhel7. Single --enable-* option arranges to build +# both client libs and server process. + +PKG_PROG_PKG_CONFIG +AC_ARG_ENABLE([debuginfod], AC_HELP_STRING([--enable-debuginfod], [Build debuginfo server and client solib])) +AS_IF([test "x$enable_debuginfod" = "xyes"], [ + AC_DEFINE([ENABLE_DEBUGINFOD],[1],[Build debuginfo-server]) + PKG_CHECK_MODULES([libmicrohttpd],[libmicrohttpd >= 0.9.33]) + PKG_CHECK_MODULES([libcurl],[libcurl >= 7.29.0]) + PKG_CHECK_MODULES([sqlite3],[sqlite3 >= 3.7.17]) + PKG_CHECK_MODULES([libarchive],[libarchive >= 3.1.2]) +], [enable_debuginfod="no"]) +AM_CONDITIONAL([DEBUGINFOD],[test "x$enable_debuginfod" = "xyes"]) + + AC_OUTPUT AC_MSG_NOTICE([ @@ -699,6 +719,7 @@ AC_MSG_NOTICE([ Deterministic archives by default : ${default_ar_deterministic} Native language support : ${USE_NLS} Extra Valgrind annotations : ${use_vg_annotations} + Debuginfo client/server support : ${enable_debuginfod} EXTRA TEST FEATURES (used with make check) have bunzip2 installed (required) : ${HAVE_BUNZIP2} diff --git a/debuginfod/ChangeLog b/debuginfod/ChangeLog new file mode 100644 index 00000000..1a31cf6f --- /dev/null +++ b/debuginfod/ChangeLog @@ -0,0 +1,9 @@ +2019-10-28 Aaron Merey + + * debuginfod-client.c: New file: debuginfod client library. + * debuginfod.h: New file: header for same. + * libdebuginfod.map: New file: govern its solib exports. + * debuginfod-find.c: New file: command line frontend. + * debuginfod-find.1, debuginfod_find_source.3, + debuginfod_find_executable.3, debuginfod_find_debuginfo.3: + New man pages. diff --git a/debuginfod/Makefile.am b/debuginfod/Makefile.am new file mode 100644 index 00000000..a8ee4594 --- /dev/null +++ b/debuginfod/Makefile.am @@ -0,0 +1,114 @@ +## Makefile.am for libdebuginfod library subdirectory in elfutils. +## +## Process this file with automake to create Makefile.in +## +## Copyright (C) 2019 Red Hat, Inc. +## This file is part of elfutils. +## +## This file is free software; you can redistribute it and/or modify +## it under the terms of either +## +## * the GNU Lesser General Public License as published by the Free +## Software Foundation; either version 3 of the License, or (at +## your option) any later version +## +## or +## +## * the GNU General Public License as published by the Free +## Software Foundation; either version 2 of the License, or (at +## your option) any later version +## +## or both in parallel, as here. +## +## elfutils 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 copies of the GNU General Public License and +## the GNU Lesser General Public License along with this program. If +## not, see . +## +include $(top_srcdir)/config/eu.am +AM_CPPFLAGS += -I$(srcdir) -I$(srcdir)/../libelf -I$(srcdir)/../libebl \ + -I$(srcdir)/../libdw -I$(srcdir)/../libdwelf +VERSION = 1 + +# Disable eu- prefixing for artifacts (binaries & man pages) in this +# directory, since they do not conflict with binutils tools. +program_prefix= +program_transform_name = s,x,x, + +if BUILD_STATIC +libasm = ../libasm/libasm.a +libdw = ../libdw/libdw.a -lz $(zip_LIBS) $(libelf) $(libebl) -ldl +libelf = ../libelf/libelf.a -lz +libdebuginfod = ./libdebuginfod.a +else +libasm = ../libasm/libasm.so +libdw = ../libdw/libdw.so +libelf = ../libelf/libelf.so +libdebuginfod = ./libdebuginfod.so +endif +libebl = ../libebl/libebl.a +libeu = ../lib/libeu.a + +AM_LDFLAGS = -Wl,-rpath-link,../libelf:../libdw:. + +bin_PROGRAMS = debuginfod-find + +debuginfod_find_SOURCES = debuginfod-find.c +debuginfod_find_LDADD = $(libeu) $(libdebuginfod) + +noinst_LIBRARIES = libdebuginfod.a +noinst_LIBRARIES += libdebuginfod_pic.a + +libdebuginfod_a_SOURCES = debuginfod-client.c +libdebuginfod_pic_a_SOURCES = debuginfod-client.c +am_libdebuginfod_pic_a_OBJECTS = $(libdebuginfod_a_SOURCES:.c=.os) + +pkginclude_HEADERS = debuginfod.h + +libdebuginfod_so_LIBS = libdebuginfod_pic.a +libdebuginfod_so_LDLIBS = $(libcurl_LIBS) +libdebuginfod.so$(EXEEXT): $(srcdir)/libdebuginfod.map $(libdebuginfod_so_LIBS) + $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $@ \ + -Wl,--soname,$@.$(VERSION) \ + -Wl,--version-script,$<,--no-undefined \ + -Wl,--whole-archive $(libdebuginfod_so_LIBS) -Wl,--no-whole-archive \ + $(libdebuginfod_so_LDLIBS) + @$(textrel_check) + $(AM_V_at)ln -fs $@ $@.$(VERSION) + +install: install-am libdebuginfod.so + $(mkinstalldirs) $(DESTDIR)$(libdir) + $(INSTALL_PROGRAM) libdebuginfod.so $(DESTDIR)$(libdir)/libdebuginfod-$(PACKAGE_VERSION).so + ln -fs libdebuginfod-$(PACKAGE_VERSION).so $(DESTDIR)$(libdir)/libdebuginfod.so.$(VERSION) + ln -fs libdebuginfod.so.$(VERSION) $(DESTDIR)$(libdir)/libdebuginfod.so + +uninstall: uninstall-am + rm -f $(DESTDIR)$(libdir)/libdebuginfod-$(PACKAGE_VERSION).so + rm -f $(DESTDIR)$(libdir)/libdebuginfod.so.$(VERSION) + rm -f $(DESTDIR)$(libdir)/libdebuginfod.so + rmdir --ignore-fail-on-non-empty $(DESTDIR)$(includedir)/elfutils + +EXTRA_DIST = libdebuginfod.map +MOSTLYCLEANFILES = $(am_libdebuginfod_pic_a_OBJECTS) libdebuginfod.so.$(VERSION) +CLEANFILES += $(am_libdebuginfod_pic_a_OBJECTS) libdebuginfod.so + +# automake std-options override: arrange to pass LD_LIBRARY_PATH +installcheck-binPROGRAMS: $(bin_PROGRAMS) + bad=0; pid=$$$$; list="$(bin_PROGRAMS)"; for p in $$list; do \ + case ' $(AM_INSTALLCHECK_STD_OPTIONS_EXEMPT) ' in \ + *" $$p "* | *" $(srcdir)/$$p "*) continue;; \ + esac; \ + f=`echo "$$p" | \ + sed 's,^.*/,,;s/$(EXEEXT)$$//;$(transform);s/$$/$(EXEEXT)/'`; \ + for opt in --help --version; do \ + if LD_LIBRARY_PATH=$(DESTDIR)$(libdir) \ + $(DESTDIR)$(bindir)/$$f $$opt > c$${pid}_.out 2> c$${pid}_.err \ + && test -n "`cat c$${pid}_.out`" \ + && test -z "`cat c$${pid}_.err`"; then :; \ + else echo "$$f does not support $$opt" 1>&2; bad=1; fi; \ + done; \ + done; rm -f c$${pid}_.???; exit $$bad diff --git a/debuginfod/debuginfod-client.c b/debuginfod/debuginfod-client.c new file mode 100644 index 00000000..1aa9edac --- /dev/null +++ b/debuginfod/debuginfod-client.c @@ -0,0 +1,665 @@ +/* Retrieve ELF / DWARF / source files from the debuginfod. + Copyright (C) 2019 Red Hat, Inc. + This file is part of elfutils. + + This file is free software; you can redistribute it and/or modify + it under the terms of either + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils 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 copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see . */ + + +/* cargo-cult from libdwfl linux-kernel-modules.c */ +/* In case we have a bad fts we include this before config.h because it + can't handle _FILE_OFFSET_BITS. + Everything we need here is fine if its declarations just come first. + Also, include sys/types.h before fts. On some systems fts.h is not self + contained. */ +#ifdef BAD_FTS + #include + #include +#endif + +#include "config.h" +#include "debuginfod.h" +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* If fts.h is included before config.h, its indirect inclusions may not + give us the right LFS aliases of these functions, so map them manually. */ +#ifdef BAD_FTS + #ifdef _FILE_OFFSET_BITS + #define open open64 + #define fopen fopen64 + #endif +#else + #include + #include +#endif + + +/* The cache_clean_interval_s file within the debuginfod cache specifies + how frequently the cache should be cleaned. The file's st_mtime represents + the time of last cleaning. */ +static const char *cache_clean_interval_filename = "cache_clean_interval_s"; +static const time_t cache_clean_default_interval_s = 86400; /* 1 day */ + +/* The cache_max_unused_age_s file within the debuginfod cache specifies the + the maximum time since last access that a file will remain in the cache. */ +static const char *cache_max_unused_age_filename = "max_unused_age_s"; +static const time_t cache_default_max_unused_age_s = 604800; /* 1 week */ + +/* Location of the cache of files downloaded from debuginfods. + The default parent directory is $HOME, or '/' if $HOME doesn't exist. */ +static const char *cache_default_name = ".debuginfod_client_cache"; +static const char *cache_path_envvar = DEBUGINFOD_CACHE_PATH_ENV_VAR; + +/* URLs of debuginfods, separated by url_delim. + This env var must be set for debuginfod-client to run. */ +static const char *server_urls_envvar = DEBUGINFOD_URLS_ENV_VAR; +static const char *url_delim = " "; +static const char url_delim_char = ' '; + +/* Timeout for debuginfods, in seconds. + This env var must be set for debuginfod-client to run. */ +static const char *server_timeout_envvar = DEBUGINFOD_TIMEOUT_ENV_VAR; +static int server_timeout = 5; + +/* Data associated with a particular CURL easy handle. Passed to + the write callback. */ +struct handle_data +{ + /* Cache file to be written to in case query is successful. */ + int fd; + + /* URL queried by this handle. */ + char url[PATH_MAX]; + + /* This handle. */ + CURL *handle; + + /* Pointer to handle that should write to fd. Initially points to NULL, + then points to the first handle that begins writing the target file + to the cache. Used to ensure that a file is not downloaded from + multiple servers unnecessarily. */ + CURL **target_handle; +}; + +static size_t +debuginfod_write_callback (char *ptr, size_t size, size_t nmemb, void *data) +{ + ssize_t count = size * nmemb; + + struct handle_data *d = (struct handle_data*)data; + + /* Indicate to other handles that they can abort their transfer. */ + if (*d->target_handle == NULL) + *d->target_handle = d->handle; + + /* If this handle isn't the target handle, abort transfer. */ + if (*d->target_handle != d->handle) + return -1; + + return (size_t) write(d->fd, (void*)ptr, count); +} + +/* Create the cache and interval file if they do not already exist. + Return 0 if cache and config file are initialized, otherwise return + the appropriate error code. */ +static int +debuginfod_init_cache (char *cache_path, char *interval_path, char *maxage_path) +{ + struct stat st; + + /* If the cache and config file already exist then we are done. */ + if (stat(cache_path, &st) == 0 && stat(interval_path, &st) == 0) + return 0; + + /* Create the cache and config files as necessary. */ + if (stat(cache_path, &st) != 0 && mkdir(cache_path, 0777) < 0) + return -errno; + + int fd = -1; + + /* init cleaning interval config file. */ + fd = open(interval_path, O_CREAT | O_RDWR, 0666); + if (fd < 0) + return -errno; + + if (dprintf(fd, "%ld", cache_clean_default_interval_s) < 0) + return -errno; + + /* init max age config file. */ + if (stat(maxage_path, &st) != 0 + && (fd = open(maxage_path, O_CREAT | O_RDWR, 0666)) < 0) + return -errno; + + if (dprintf(fd, "%ld", cache_default_max_unused_age_s) < 0) + return -errno; + + return 0; +} + + +/* Delete any files that have been unmodied for a period + longer than $DEBUGINFOD_CACHE_CLEAN_INTERVAL_S. */ +static int +debuginfod_clean_cache(char *cache_path, char *interval_path, char *max_unused_path) +{ + struct stat st; + FILE *interval_file; + FILE *max_unused_file; + + if (stat(interval_path, &st) == -1) + { + /* Create new interval file. */ + interval_file = fopen(interval_path, "w"); + + if (interval_file == NULL) + return -errno; + + int rc = fprintf(interval_file, "%ld", cache_clean_default_interval_s); + fclose(interval_file); + + if (rc < 0) + return -errno; + } + + /* Check timestamp of interval file to see whether cleaning is necessary. */ + time_t clean_interval; + interval_file = fopen(interval_path, "r"); + if (fscanf(interval_file, "%ld", &clean_interval) != 1) + clean_interval = cache_clean_default_interval_s; + fclose(interval_file); + + if (time(NULL) - st.st_mtime < clean_interval) + /* Interval has not passed, skip cleaning. */ + return 0; + + /* Read max unused age value from config file. */ + time_t max_unused_age; + max_unused_file = fopen(max_unused_path, "r"); + if (max_unused_file) + { + if (fscanf(max_unused_file, "%ld", &max_unused_age) != 1) + max_unused_age = cache_default_max_unused_age_s; + fclose(max_unused_file); + } + else + max_unused_age = cache_default_max_unused_age_s; + + char * const dirs[] = { cache_path, NULL, }; + + FTS *fts = fts_open(dirs, 0, NULL); + if (fts == NULL) + return -errno; + + FTSENT *f; + while ((f = fts_read(fts)) != NULL) + { + switch (f->fts_info) + { + case FTS_F: + /* delete file if max_unused_age has been met or exceeded. */ + /* XXX consider extra effort to clean up old tmp files */ + if (time(NULL) - f->fts_statp->st_atime >= max_unused_age) + unlink (f->fts_path); + break; + + case FTS_DP: + /* Remove if empty. */ + (void) rmdir (f->fts_path); + break; + + default: + ; + } + } + fts_close(fts); + + /* Update timestamp representing when the cache was last cleaned. */ + utime (interval_path, NULL); + return 0; +} + + +#define MAX_BUILD_ID_BYTES 64 + + +/* Query each of the server URLs found in $DEBUGINFOD_URLS for the file + with the specified build-id, type (debuginfo, executable or source) + and filename. filename may be NULL. If found, return a file + descriptor for the target, otherwise return an error code. */ +static int +debuginfod_query_server (const unsigned char *build_id, + int build_id_len, + const char *type, + const char *filename, + char **path) +{ + char *urls_envvar; + char *server_urls; + char cache_path[PATH_MAX]; + char maxage_path[PATH_MAX*3]; /* These *3 multipliers are to shut up gcc -Wformat-truncation */ + char interval_path[PATH_MAX*4]; + char target_cache_dir[PATH_MAX*2]; + char target_cache_path[PATH_MAX*4]; + char target_cache_tmppath[PATH_MAX*5]; + char suffix[PATH_MAX*2]; + char build_id_bytes[MAX_BUILD_ID_BYTES * 2 + 1]; + + /* Copy lowercase hex representation of build_id into buf. */ + if ((build_id_len >= MAX_BUILD_ID_BYTES) || + (build_id_len == 0 && + sizeof(build_id_bytes) > MAX_BUILD_ID_BYTES*2 + 1)) + return -EINVAL; + if (build_id_len == 0) /* expect clean hexadecimal */ + strcpy (build_id_bytes, (const char *) build_id); + else + for (int i = 0; i < build_id_len; i++) + sprintf(build_id_bytes + (i * 2), "%02x", build_id[i]); + + if (filename != NULL) + { + if (filename[0] != '/') // must start with / + return -EINVAL; + + /* copy the filename to suffix, s,/,#,g */ + unsigned q = 0; + for (unsigned fi=0; q < PATH_MAX-1; fi++) + switch (filename[fi]) + { + case '\0': + suffix[q] = '\0'; + q = PATH_MAX-1; /* escape for loop too */ + break; + case '/': /* escape / to prevent dir escape */ + suffix[q++]='#'; + suffix[q++]='#'; + break; + case '#': /* escape # to prevent /# vs #/ collisions */ + suffix[q++]='#'; + suffix[q++]='_'; + break; + default: + suffix[q++]=filename[fi]; + } + suffix[q] = '\0'; + /* If the DWARF filenames are super long, this could exceed + PATH_MAX and truncate/collide. Oh well, that'll teach + them! */ + } + else + suffix[0] = '\0'; + + /* set paths needed to perform the query + + example format + cache_path: $HOME/.debuginfod_cache + target_cache_dir: $HOME/.debuginfod_cache/0123abcd + target_cache_path: $HOME/.debuginfod_cache/0123abcd/debuginfo + target_cache_path: $HOME/.debuginfod_cache/0123abcd/source#PATH#TO#SOURCE ? + */ + + if (getenv(cache_path_envvar)) + strcpy(cache_path, getenv(cache_path_envvar)); + else + { + if (getenv("HOME")) + sprintf(cache_path, "%s/%s", getenv("HOME"), cache_default_name); + else + sprintf(cache_path, "/%s", cache_default_name); + } + + /* avoid using snprintf here due to compiler warning. */ + snprintf(target_cache_dir, sizeof(target_cache_dir), "%s/%s", cache_path, build_id_bytes); + snprintf(target_cache_path, sizeof(target_cache_path), "%s/%s%s", target_cache_dir, type, suffix); + snprintf(target_cache_tmppath, sizeof(target_cache_tmppath), "%s.XXXXXX", target_cache_path); + + /* XXX combine these */ + snprintf(interval_path, sizeof(interval_path), "%s/%s", cache_path, cache_clean_interval_filename); + snprintf(maxage_path, sizeof(maxage_path), "%s/%s", cache_path, cache_max_unused_age_filename); + int rc = debuginfod_init_cache(cache_path, interval_path, maxage_path); + if (rc != 0) + goto out; + rc = debuginfod_clean_cache(cache_path, interval_path, maxage_path); + if (rc != 0) + goto out; + + /* If the target is already in the cache then we are done. */ + int fd = open (target_cache_path, O_RDONLY); + if (fd >= 0) + { + /* Success!!!! */ + if (path != NULL) + *path = strdup(target_cache_path); + return fd; + } + + + urls_envvar = getenv(server_urls_envvar); + if (urls_envvar == NULL || urls_envvar[0] == '\0') + { + rc = -ENOSYS; + goto out; + } + + if (getenv(server_timeout_envvar)) + server_timeout = atoi (getenv(server_timeout_envvar)); + + /* make a copy of the envvar so it can be safely modified. */ + server_urls = strdup(urls_envvar); + if (server_urls == NULL) + { + rc = -ENOMEM; + goto out; + } + /* thereafter, goto out0 on error*/ + + /* create target directory in cache if not found. */ + struct stat st; + if (stat(target_cache_dir, &st) == -1 && mkdir(target_cache_dir, 0700) < 0) + { + rc = -errno; + goto out0; + } + + /* NB: write to a temporary file first, to avoid race condition of + multiple clients checking the cache, while a partially-written or empty + file is in there, being written from libcurl. */ + fd = mkstemp (target_cache_tmppath); + if (fd < 0) + { + rc = -errno; + goto out0; + } + + /* Count number of URLs. */ + int num_urls = 0; + for (int i = 0; server_urls[i] != '\0'; i++) + if (server_urls[i] != url_delim_char + && (i == 0 || server_urls[i - 1] == url_delim_char)) + num_urls++; + + /* Tracks which handle should write to fd. Set to the first + handle that is ready to write the target file to the cache. */ + CURL *target_handle = NULL; + struct handle_data *data = malloc(sizeof(struct handle_data) * num_urls); + + /* Initalize handle_data with default values. */ + for (int i = 0; i < num_urls; i++) + { + data[i].handle = NULL; + data[i].fd = -1; + } + + CURLM *curlm = curl_multi_init(); + if (curlm == NULL) + { + rc = -ENETUNREACH; + goto out0; + } + /* thereafter, goto out1 on error. */ + + char *strtok_saveptr; + char *server_url = strtok_r(server_urls, url_delim, &strtok_saveptr); + + /* Initialize each handle. */ + for (int i = 0; i < num_urls && server_url != NULL; i++) + { + data[i].fd = fd; + data[i].target_handle = &target_handle; + data[i].handle = curl_easy_init(); + + if (data[i].handle == NULL) + { + rc = -ENETUNREACH; + goto out1; + } + + /* Build handle url. Tolerate both http://foo:999 and + http://foo:999/ forms */ + char *slashbuildid; + if (strlen(server_url) > 1 && server_url[strlen(server_url)-1] == '/') + slashbuildid = "buildid"; + else + slashbuildid = "/buildid"; + + if (filename) /* must start with / */ + snprintf(data[i].url, PATH_MAX, "%s%s/%s/%s%s", server_url, + slashbuildid, build_id_bytes, type, filename); + else + snprintf(data[i].url, PATH_MAX, "%s%s/%s/%s", server_url, + slashbuildid, build_id_bytes, type); + + curl_easy_setopt(data[i].handle, CURLOPT_URL, data[i].url); + curl_easy_setopt(data[i].handle, + CURLOPT_WRITEFUNCTION, + debuginfod_write_callback); + curl_easy_setopt(data[i].handle, CURLOPT_WRITEDATA, (void*)&data[i]); + curl_easy_setopt(data[i].handle, CURLOPT_TIMEOUT, (long) server_timeout); + curl_easy_setopt(data[i].handle, CURLOPT_FILETIME, (long) 1); + curl_easy_setopt(data[i].handle, CURLOPT_FOLLOWLOCATION, (long) 1); + curl_easy_setopt(data[i].handle, CURLOPT_FAILONERROR, (long) 1); + curl_easy_setopt(data[i].handle, CURLOPT_NOSIGNAL, (long) 1); + curl_easy_setopt(data[i].handle, CURLOPT_AUTOREFERER, (long) 1); + curl_easy_setopt(data[i].handle, CURLOPT_ACCEPT_ENCODING, ""); + curl_easy_setopt(data[i].handle, CURLOPT_USERAGENT, (void*) PACKAGE_STRING); + + curl_multi_add_handle(curlm, data[i].handle); + server_url = strtok_r(NULL, url_delim, &strtok_saveptr); + } + + /* Query servers in parallel. */ + int still_running; + do + { + CURLMcode curl_res; + + /* Wait 1 second, the minimum DEBUGINFOD_TIMEOUT. */ + curl_multi_wait(curlm, NULL, 0, 1000, NULL); + + /* If the target file has been found, abort the other queries. */ + if (target_handle != NULL) + for (int i = 0; i < num_urls; i++) + if (data[i].handle != target_handle) + curl_multi_remove_handle(curlm, data[i].handle); + + curl_res = curl_multi_perform(curlm, &still_running); + if (curl_res != CURLM_OK) + { + switch (curl_res) + { + case CURLM_CALL_MULTI_PERFORM: continue; + case CURLM_OUT_OF_MEMORY: rc = -ENOMEM; break; + default: rc = -ENETUNREACH; break; + } + goto out1; + } + } while (still_running); + + /* Check whether a query was successful. If so, assign its handle + to verified_handle. */ + int num_msg; + rc = -ENOENT; + CURL *verified_handle = NULL; + do + { + CURLMsg *msg; + + msg = curl_multi_info_read(curlm, &num_msg); + if (msg != NULL && msg->msg == CURLMSG_DONE) + { + if (msg->data.result != CURLE_OK) + { + /* Unsucessful query, determine error code. */ + switch (msg->data.result) + { + case CURLE_COULDNT_RESOLVE_HOST: rc = -EHOSTUNREACH; break; // no NXDOMAIN + case CURLE_URL_MALFORMAT: rc = -EINVAL; break; + case CURLE_COULDNT_CONNECT: rc = -ECONNREFUSED; break; + case CURLE_REMOTE_ACCESS_DENIED: rc = -EACCES; break; + case CURLE_WRITE_ERROR: rc = -EIO; break; + case CURLE_OUT_OF_MEMORY: rc = -ENOMEM; break; + case CURLE_TOO_MANY_REDIRECTS: rc = -EMLINK; break; + case CURLE_SEND_ERROR: rc = -ECONNRESET; break; + case CURLE_RECV_ERROR: rc = -ECONNRESET; break; + case CURLE_OPERATION_TIMEDOUT: rc = -ETIME; break; + default: rc = -ENOENT; break; + } + } + else + { + /* Query completed without an error. Confirm that the + response code is 200 and set verified_handle. */ + long resp_code = 500; + CURLcode curl_res; + + curl_res = curl_easy_getinfo(target_handle, + CURLINFO_RESPONSE_CODE, + &resp_code); + + if (curl_res == CURLE_OK + && resp_code == 200 + && msg->easy_handle != NULL) + { + verified_handle = msg->easy_handle; + break; + } + } + } + } while (num_msg > 0); + + if (verified_handle == NULL) + goto out1; + + /* we've got one!!!! */ + time_t mtime; + CURLcode curl_res = curl_easy_getinfo(verified_handle, CURLINFO_FILETIME, (void*) &mtime); + if (curl_res != CURLE_OK) + mtime = time(NULL); /* fall back to current time */ + + struct timeval tvs[2]; + tvs[0].tv_sec = tvs[1].tv_sec = mtime; + tvs[0].tv_usec = tvs[1].tv_usec = 0; + (void) futimes (fd, tvs); /* best effort */ + + /* rename tmp->real */ + rc = rename (target_cache_tmppath, target_cache_path); + if (rc < 0) + { + rc = -errno; + goto out1; + /* Perhaps we need not give up right away; could retry or something ... */ + } + + /* Success!!!! */ + for (int i = 0; i < num_urls; i++) + curl_easy_cleanup(data[i].handle); + + curl_multi_cleanup (curlm); + free (data); + free (server_urls); + /* don't close fd - we're returning it */ + /* don't unlink the tmppath; it's already been renamed. */ + if (path != NULL) + *path = strdup(target_cache_path); + + return fd; + +/* error exits */ + out1: + for (int i = 0; i < num_urls; i++) + curl_easy_cleanup(data[i].handle); + + curl_multi_cleanup(curlm); + unlink (target_cache_tmppath); + (void) rmdir (target_cache_dir); /* nop if not empty */ + free(data); + close (fd); + + out0: + free (server_urls); + + out: + return rc; +} + + +/* See debuginfod.h */ +int +debuginfod_find_debuginfo (const unsigned char *build_id, int build_id_len, + char **path) +{ + return debuginfod_query_server(build_id, build_id_len, + "debuginfo", NULL, path); +} + + +/* See debuginfod.h */ +int +debuginfod_find_executable(const unsigned char *build_id, int build_id_len, + char **path) +{ + return debuginfod_query_server(build_id, build_id_len, + "executable", NULL, path); +} + +/* See debuginfod.h */ +int debuginfod_find_source(const unsigned char *build_id, + int build_id_len, + const char *filename, + char **path) +{ + return debuginfod_query_server(build_id, build_id_len, + "source", filename, path); +} + + + +/* NB: these are thread-unsafe. */ +__attribute__((constructor)) attribute_hidden void libdebuginfod_ctor(void) +{ + curl_global_init(CURL_GLOBAL_DEFAULT); +} + +/* NB: this is very thread-unsafe: it breaks other threads that are still in libcurl */ +__attribute__((destructor)) attribute_hidden void libdebuginfod_dtor(void) +{ + /* ... so don't do this: */ + /* curl_global_cleanup(); */ +} diff --git a/debuginfod/debuginfod-find.c b/debuginfod/debuginfod-find.c new file mode 100644 index 00000000..ff47b807 --- /dev/null +++ b/debuginfod/debuginfod-find.c @@ -0,0 +1,101 @@ +/* Command-line frontend for retrieving ELF / DWARF / source files + from the debuginfod. + Copyright (C) 2019 Red Hat, Inc. + This file is part of elfutils. + + This file 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 of the License, or + (at your option) any later version. + + elfutils 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 copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see . */ + +#include "config.h" +#include "printversion.h" +#include "debuginfod.h" +#include +#include +#include +#include +#include + + +/* Name and version of program. */ +ARGP_PROGRAM_VERSION_HOOK_DEF = print_version; + +/* Bug report address. */ +ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT; + +/* Short description of program. */ +static const char doc[] = N_("Request debuginfo-related content " + "from debuginfods listed in $" DEBUGINFOD_URLS_ENV_VAR "."); + +/* Strings for arguments in help texts. */ +static const char args_doc[] = N_("debuginfo BUILDID\n" + "executable BUILDID\n" + "source BUILDID /FILENAME"); + +/* Data structure to communicate with argp functions. */ +static struct argp argp = + { + NULL, NULL, args_doc, doc, NULL, NULL, NULL + }; + + + +int +main(int argc, char** argv) +{ + int remaining; + (void) argp_parse (&argp, argc, argv, ARGP_IN_ORDER|ARGP_NO_ARGS, &remaining, NULL); + + if (argc < 2 || remaining+1 == argc) /* no arguments or at least two non-option words */ + { + argp_help (&argp, stderr, ARGP_HELP_USAGE, argv[0]); + return 1; + } + + int rc; + char *cache_name; + + /* Check whether FILETYPE is valid and call the appropriate + debuginfod_find_* function. If FILETYPE is "source" + then ensure a FILENAME was also supplied as an argument. */ + if (strcmp(argv[remaining], "debuginfo") == 0) + rc = debuginfod_find_debuginfo((unsigned char *)argv[remaining+1], 0, &cache_name); + else if (strcmp(argv[remaining], "executable") == 0) + rc = debuginfod_find_executable((unsigned char *)argv[remaining+1], 0, &cache_name); + else if (strcmp(argv[remaining], "source") == 0) + { + if (remaining+2 == argc || argv[3][0] != '/') + { + fprintf(stderr, "If FILETYPE is \"source\" then absolute /FILENAME must be given\n"); + return 1; + } + rc = debuginfod_find_source((unsigned char *)argv[remaining+1], 0, + argv[remaining+2], &cache_name); + } + else + { + argp_help (&argp, stderr, ARGP_HELP_USAGE, argv[0]); + return 1; + } + + if (rc < 0) + { + fprintf(stderr, "Server query failed: %s\n", strerror(-rc)); + return 1; + } + + printf("%s\n", cache_name); + + free (cache_name); + return 0; +} diff --git a/debuginfod/debuginfod.h b/debuginfod/debuginfod.h new file mode 100644 index 00000000..d2bb0c94 --- /dev/null +++ b/debuginfod/debuginfod.h @@ -0,0 +1,69 @@ +/* External declarations for the libdebuginfod client library. + Copyright (C) 2019 Red Hat, Inc. + This file is part of elfutils. + + This file is free software; you can redistribute it and/or modify + it under the terms of either + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at + your option) any later version + + or + + * the GNU General Public License as published by the Free + Software Foundation; either version 2 of the License, or (at + your option) any later version + + or both in parallel, as here. + + elfutils 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 copies of the GNU General Public License and + the GNU Lesser General Public License along with this program. If + not, see . */ + +#ifndef _DEBUGINFOD_CLIENT_H +#define _DEBUGINFOD_CLIENT_H 1 + +/* Names of environment variables that control the client logic. */ +#define DEBUGINFOD_URLS_ENV_VAR "DEBUGINFOD_URLS" +#define DEBUGINFOD_CACHE_PATH_ENV_VAR "DEBUGINFOD_CACHE_PATH" +#define DEBUGINFOD_TIMEOUT_ENV_VAR "DEBUGINFOD_TIMEOUT" + +#ifdef __cplusplus +extern "C" { +#endif + +/* Query the urls contained in $DEBUGINFOD_URLS for a file with + the specified type and build id. If build_id_len == 0, the + build_id is supplied as a lowercase hexadecimal string; otherwise + it is a binary blob of given legnth. + + If successful, return a file descriptor to the target, otherwise + return a posix error code. If successful, set *path to a + strdup'd copy of the name of the same file in the cache. + Caller must free() it later. */ + +int debuginfod_find_debuginfo (const unsigned char *build_id, + int build_id_len, + char **path); + +int debuginfod_find_executable (const unsigned char *build_id, + int build_id_len, + char **path); + +int debuginfod_find_source (const unsigned char *build_id, + int build_id_len, + const char *filename, + char **path); + +#ifdef __cplusplus +} +#endif + + +#endif /* _DEBUGINFOD_CLIENT_H */ diff --git a/debuginfod/libdebuginfod.map b/debuginfod/libdebuginfod.map new file mode 100644 index 00000000..4d3daf32 --- /dev/null +++ b/debuginfod/libdebuginfod.map @@ -0,0 +1,7 @@ +ELFUTILS_0 { }; +ELFUTILS_0.178 { + global: + debuginfod_find_debuginfo; + debuginfod_find_executable; + debuginfod_find_source; +} ELFUTILS_0; diff --git a/doc/Makefile.am b/doc/Makefile.am index d6f3eca8..23102604 100644 --- a/doc/Makefile.am +++ b/doc/Makefile.am @@ -1,7 +1,7 @@ ## Process this file with automake to create Makefile.in ## Configure input file for elfutils. ## -## Copyright (C) 1996-2001, 2002, 2005 Red Hat, Inc. +## Copyright (C) 1996-2001, 2002, 2005, 2019 Red Hat, Inc. ## This file is part of elfutils. ## ## This file is free software; you can redistribute it and/or modify @@ -19,3 +19,11 @@ EXTRA_DIST = COPYING-GFDL README dist_man1_MANS=readelf.1 elfclassify.1 notrans_dist_man3_MANS=elf_update.3 elf_getdata.3 elf_clone.3 elf_begin.3 + +notrans_dist_man1_MANS= + +if DEBUGINFOD +notrans_dist_man3_MANS += debuginfod_find_debuginfo.3 debuginfod_find_source.3 debuginfod_find_executable.3 +notrans_dist_man1_MANS += debuginfod-find.1 +endif + diff --git a/doc/debuginfod-find.1 b/doc/debuginfod-find.1 new file mode 100644 index 00000000..ab2f4d17 --- /dev/null +++ b/doc/debuginfod-find.1 @@ -0,0 +1,137 @@ +'\"! tbl | nroff \-man +'\" t macro stdmacro + +.de SAMPLE +.br +.RS 0 +.nf +.nh +.. +.de ESAMPLE +.hy +.fi +.RE +.. + +.TH DEBUGINFOD-FIND 1 +.SH NAME +debuginfod-find \- request debuginfo-related data + +.SH SYNOPSIS +.B debuginfod-find debuginfo \fIBUILDID\fP + +.B debuginfod-find executable \fIBUILDID\fP + +.B debuginfod-find source \fIBUILDID\fP \fI/FILENAME\fP + +.SH DESCRIPTION +\fBdebuginfod-find\fP queries one or more \fBdebuginfod\fP servers for +debuginfo-related data. In case of a match, it saves the the +requested file into a local cache, prints the file name to standard +output, and exits with a success status of 0. In case of any error, +it exits with a failure status and an error message to standard error. + +.\" Much of the following text is duplicated with debuginfod.8 + +The debuginfod system uses buildids to identify debuginfo-related data. +These are stored as binary notes in ELF/DWARF files, and are +represented as lowercase hexadecimal. For example, for a program +/bin/ls, look at the ELF note GNU_BUILD_ID: + +.SAMPLE +% readelf -n /bin/ls | grep -A4 build.id +Note section [ 4] '.note.gnu.buildid' of 36 bytes at offset 0x340: +Owner Data size Type +GNU 20 GNU_BUILD_ID +Build ID: 8713b9c3fb8a720137a4a08b325905c7aaf8429d +.ESAMPLE + +Then the hexadecimal BUILDID is simply: + +.SAMPLE +8713b9c3fb8a720137a4a08b325905c7aaf8429d +.ESAMPLE + +.SS debuginfo \fIBUILDID\fP + +If the given buildid is known to a server, this request will result +in a binary object that contains the customary \fB.*debug_*\fP +sections. This may be a split debuginfo file as created by +\fBstrip\fP, or it may be an original unstripped executable. + +.SS executable \fIBUILDID\fP + +If the given buildid is known to the server, this request will result +in a binary object that contains the normal executable segments. This +may be a executable stripped by \fBstrip\fP, or it may be an original +unstripped executable. \fBET_DYN\fP shared libraries are considered +to be a type of executable. + +.SS source \fIBUILDID\fP \fI/SOURCE/FILE\fP + +If the given buildid is known to the server, this request will result +in a binary object that contains the source file mentioned. The path +should be absolute. Relative path names commonly appear in the DWARF +file's source directory, but these paths are relative to +individual compilation unit AT_comp_dir paths, and yet an executable +is made up of multiple CUs. Therefore, to disambiguate, debuginfod +expects source queries to prefix relative path names with the CU +compilation-directory, followed by a mandatory "/". + +Note: the user should not elide \fB../\fP or \fB/./\fP or extraneous +\fB///\fP sorts of path components in the directory names, because if +this is how those names appear in the DWARF files, that is what +debuginfod needs to see too. + +For example: +.TS +l l. +#include source BUILDID /usr/include/stdio.h +/path/to/foo.c source BUILDID /path/to/foo.c +\../bar/foo.c AT_comp_dir=/zoo/ source BUILDID /zoo//../bar/foo.c +.TE + +.SH "SECURITY" + +debuginfod-find \fBdoes not\fP include any particular security +features. It trusts that the binaries returned by the debuginfod(s) +are accurate. Therefore, the list of servers should include only +trustworthy ones. If accessed across HTTP rather than HTTPS, the +network should be trustworthy. Authentication information through +the internal \fIlibcurl\fP library is not currently enabled, except +for the basic plaintext \%\fIhttp[s]://userid:password@hostname/\fP style. +(The debuginfod server does not perform authentication, but a front-end +proxy server could.) + +.SH "ENVIRONMENT VARIABLES" + +.TP 21 +.B DEBUGINFOD_URLS +This environment variable contains a list of URL prefixes for trusted +debuginfod instances. Alternate URL prefixes are separated by space. + +.TP 21 +.B DEBUGINFOD_TIMEOUT +This environment variable governs the timeout for each debuginfod HTTP +connection. A server that fails to respond within this many seconds +is skipped. The default is 5. + +.TP 21 +.B DEBUGINFOD_CACHE_PATH +This environment variable governs the location of the cache where +downloaded files are kept. It is cleaned periodically as this program +is reexecuted. Cache management parameters may be set by files under +this directory: see the \fBdebuginfod_find_debuginfo(3)\fP man page +for details. The default is $HOME/.debuginfod_client_cache. + +.SH "FILES" +.LP +.PD .1v +.TP 20 +.B $HOME/.debuginfod_client_cache +Default cache directory. +.PD + +.SH "SEE ALSO" +.I "debuginfod(8)" +.I "debuginfod_find_debuginfod(3)" diff --git a/doc/debuginfod_find_debuginfo.3 b/doc/debuginfod_find_debuginfo.3 new file mode 100644 index 00000000..e0923d8d --- /dev/null +++ b/doc/debuginfod_find_debuginfo.3 @@ -0,0 +1,182 @@ +'\"! tbl | nroff \-man +'\" t macro stdmacro + +.de SAMPLE +.br +.RS 0 +.nf +.nh +.. +.de ESAMPLE +.hy +.fi +.RE +.. + +.TH DEBUGINFOD_FIND_DEBUGINFO 3 +.SH NAME +debuginfod_find_debuginfo \- request debuginfo from debuginfod + +.SH SYNOPSIS +.nf +.B #include +.PP +.BI "debuginfod_find_debuginfo(const unsigned char *" build_id ", int " build_id_len ", char ** " path ");" +.BI "debuginfod_find_executable(const unsigned char *" build_id ", int " build_id_len ", char ** " path ");" +.BI "debuginfod_find_source(const unsigned char *" build_id ", int " build_id_len ", const char *" filename ", char ** " path ");" + +.SH DESCRIPTION +.BR debuginfod_find_debuginfo (), +.BR debuginfod_find_executable (), +and +.BR debuginfod_find_source () +query the debuginfod server URLs contained in +.BR $DEBUGINFOD_URLS +(see below) for the debuginfo, executable or source file with the +given \fIbuild_id\fP. \fIbuild_id\fP should be a pointer to either +a null-terminated, lowercase hex string or a binary blob. If +\fIbuild_id\fP is given as a hex string, \fIbuild_id_len\fP should +be 0. Otherwise \fIbuild_id_len\fP should be the number of bytes in +the binary blob. + +.BR debuginfod_find_source () +also requries a \fIfilename\fP in order to specify a particular +source file. \fIfilename\fP should be an absolute path that includes +the compilation directory of the CU associated with the source file. +Relative path names commonly appear in the DWARF file's source directory, +but these paths are relative to individual compilation unit AT_comp_dir +paths, and yet an executable is made up of multiple CUs. Therefore, to +disambiguate, debuginfod expects source queries to prefix relative path +names with the CU compilation-directory, followed by a mandatory "/". + +Note: the caller should not elide \fB../\fP or \fB/./\fP or extraneous +\fB///\fP sorts of path components in the directory names, because if +this is how those names appear in the DWARF files, that is what +debuginfod needs to see too. + +If \fIpath\fP is not NULL and the query is successful, \fIpath\fP is set +to the path of the file in the cache. The caller must \fBfree\fP() this value. + +The URLs in \fB$DEBUGINFOD_URLS\fP are queried in parallel. As soon as a +debuginfod server begins transfering the target file all of the connections +to the other servers are closed. + +.SH "CACHE" +If the query is successful, the \fBdebuginfod_find_*\fP() functions save +the target file to a local cache. The location of the cache is controlled +by the \fB$DEBUGINFOD_CACHE_PATH\fP environment variable (see below). +Cleaning of the cache is controlled by the \fIcache_clean_interval_s\fP +and \fImax_unused_age_s\fP files, which are found in the +\fB$DEBUGINFOD_CACHE_PATH\fP directory. \fIcache_clean_interval_s\fP controls +how frequently the cache is traversed for cleaning and \fImax_unused_age_s\fP +controls how long a file can go unused (fstat(2) atime) before it's +removed from the cache during cleaning. These files should contain only an +ASCII decimal integer representing the interval or max unused age in seconds. +The default is one day and one week, respectively. Values of zero mean "immediately". + +.SH "SECURITY" +.BR debuginfod_find_debuginfo (), +.BR debuginfod_find_executable (), +and +.BR debuginfod_find_source () +\fBdo not\fP include any particular security +features. They trust that the binaries returned by the debuginfod(s) +are accurate. Therefore, the list of servers should include only +trustworthy ones. If accessed across HTTP rather than HTTPS, the +network should be trustworthy. Passing user authentication information +through the internal \fIlibcurl\fP library is not currently enabled, except +for the basic plaintext \%\fIhttp[s]://userid:password@hostname/\fP style. +(The debuginfod server does not perform authentication, but a front-end +proxy server could.) + +.SH "ENVIRONMENT VARIABLES" + +.TP 21 +.B DEBUGINFOD_URLS +This environment variable contains a list of URL prefixes for trusted +debuginfod instances. Alternate URL prefixes are separated by space. + +.TP 21 +.B DEBUGINFOD_TIMEOUT +This environment variable governs the timeout for each debuginfod HTTP +connection. A server that fails to respond within this many seconds +is skipped. The default is 5. + +.TP 21 +.B DEBUGINFOD_CACHE_PATH +This environment variable governs the location of the cache where +downloaded files are kept. It is cleaned periodically as this +program is reexecuted. The default is $HOME/.debuginfod_client_cache. + +.SH "RETURN VALUE" +If the query is successful, these functions save the target file +to the client cache and return a file descriptor to that file. +Otherwise an error code is returned. + +.SH "ERRORS" +The following list is not comprehensive. Error codes may also +originate from calls to various C Library functions. + +.TP +.BR EACCESS +Denied access to resource located at the URL. + +.TP +.BR ECONNREFUSED +Unable to connect to remote host. + +.TP +.BR ECONNRESET +Unable to either send or recieve network data. + +.TP +.BR EHOSTUNREACH +Unable to resolve remote host. + +.TP +.BR EINVAL +One or more arguments are incorrectly formatted. \fIbuild_id\fP may +be too long (greater than 256 characters), \fIfilename\fP may not +be an absolute path or a debuginfod URL is malformed. + +.TP +.BR EIO +Unable to write data received from server to local file. + +.TP +.BR EMLINK +Too many HTTP redirects. + +.TP +.BR ENETUNREACH +Unable to initialize network connection. + +.TP +.BR ENOENT +Could not find the resource located at URL. Often this error code +indicates that a debuginfod server was successfully contacted but +the server could not find the target file. + +.TP +.BR ENOMEM +System is unable to allocate resources. + +.TP +.BR ENOSYS +\fB$DEBUGINFOD_URLS\fP is not defined. + +.TP +.BR ETIME +Query failed due to timeout. \fB$DEBUGINFOD_TIMEOUT\fP controls +the timeout duration. See debuginfod(8) for more information. + +.SH "FILES" +.LP +.PD .1v +.TP 20 +.B $HOME/.debuginfod_client_cache +Default cache directory. +.PD + +.SH "SEE ALSO" +.I "debuginfod(8)" diff --git a/doc/debuginfod_find_executable.3 b/doc/debuginfod_find_executable.3 new file mode 100644 index 00000000..16279936 --- /dev/null +++ b/doc/debuginfod_find_executable.3 @@ -0,0 +1 @@ +.so man3/debuginfod_find_debuginfo.3 diff --git a/doc/debuginfod_find_source.3 b/doc/debuginfod_find_source.3 new file mode 100644 index 00000000..16279936 --- /dev/null +++ b/doc/debuginfod_find_source.3 @@ -0,0 +1 @@ +.so man3/debuginfod_find_debuginfo.3 diff --git a/libdw/ChangeLog b/libdw/ChangeLog index 95ac28a7..59f33f9e 100644 --- a/libdw/ChangeLog +++ b/libdw/ChangeLog @@ -1,3 +1,7 @@ +2019-10-28 Aaron Merey + + * Makefile.am (libdw_so_LDLIBS): Add -ldl for libdebuginfod.so dlopen. + 2019-11-10 Mark Wielaard * libdwP.h (libdw_unalloc): New define. diff --git a/libdw/Makefile.am b/libdw/Makefile.am index ce793e90..33b5838d 100644 --- a/libdw/Makefile.am +++ b/libdw/Makefile.am @@ -109,7 +109,7 @@ libdw_so_LIBS = ../libebl/libebl_pic.a ../backends/libebl_backends_pic.a \ ../libcpu/libcpu_pic.a libdw_pic.a ../libdwelf/libdwelf_pic.a \ ../libdwfl/libdwfl_pic.a libdw_so_DEPS = ../lib/libeu.a ../libelf/libelf.so -libdw_so_LDLIBS = $(libdw_so_DEPS) -lz $(argp_LDADD) $(zip_LIBS) -pthread +libdw_so_LDLIBS = $(libdw_so_DEPS) -ldl -lz $(argp_LDADD) $(zip_LIBS) -pthread libdw_so_SOURCES = libdw.so$(EXEEXT): $(srcdir)/libdw.map $(libdw_so_LIBS) $(libdw_so_DEPS) $(AM_V_CCLD)$(LINK) $(dso_LDFLAGS) -o $@ \ diff --git a/libdwfl/ChangeLog b/libdwfl/ChangeLog index 07a1e8df..b8222189 100644 --- a/libdwfl/ChangeLog +++ b/libdwfl/ChangeLog @@ -1,3 +1,9 @@ +2019-10-28 Aaron Merey + + * dwfl_build_id_find_elf.c (dwfl_build_id_find_elf): Call debuginfod + client functions via dlopen to look for elf/dwarf files as fallback. + * find-debuginfo.c (dwfl_standard_find_debuginfo): Ditto. + 2019-10-07 Omar Sandoval * dwfl_frame.c (dwfl_getthreads): Get rid of unnecessary diff --git a/libdwfl/Makefile.am b/libdwfl/Makefile.am index 89ca92ed..29046e9e 100644 --- a/libdwfl/Makefile.am +++ b/libdwfl/Makefile.am @@ -31,7 +31,7 @@ ## include $(top_srcdir)/config/eu.am AM_CPPFLAGS += -I$(srcdir) -I$(srcdir)/../libelf -I$(srcdir)/../libebl \ - -I$(srcdir)/../libdw -I$(srcdir)/../libdwelf + -I$(srcdir)/../libdw -I$(srcdir)/../libdwelf -I$(srcdir)/../debuginfod VERSION = 1 noinst_LIBRARIES = libdwfl.a @@ -39,6 +39,7 @@ noinst_LIBRARIES += libdwfl_pic.a pkginclude_HEADERS = libdwfl.h + libdwfl_a_SOURCES = dwfl_begin.c dwfl_end.c dwfl_error.c dwfl_version.c \ dwfl_module.c dwfl_report_elf.c relocate.c \ dwfl_module_build_id.c dwfl_module_report_build_id.c \ diff --git a/libdwfl/dwfl_build_id_find_elf.c b/libdwfl/dwfl_build_id_find_elf.c index cc6c3f62..b775f50a 100644 --- a/libdwfl/dwfl_build_id_find_elf.c +++ b/libdwfl/dwfl_build_id_find_elf.c @@ -1,5 +1,5 @@ /* Find an ELF file for a module from its build ID. - Copyright (C) 2007-2010, 2014, 2015 Red Hat, Inc. + Copyright (C) 2007-2010, 2014, 2015, 2019 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -34,7 +34,9 @@ #include #include #include +#include #include "system.h" +#include "debuginfod.h" int @@ -187,7 +189,33 @@ dwfl_build_id_find_elf (Dwfl_Module *mod, free (*file_name); *file_name = NULL; } - else if (errno == 0 && mod->build_id_len > 0) + else { + /* NB: this is slightly thread-unsafe */ + static __typeof__ (debuginfod_find_executable) *fp_debuginfod_find_executable; + + if (fp_debuginfod_find_executable == NULL) + { + void *debuginfod_so = dlopen("libdebuginfod-" VERSION ".so", RTLD_LAZY); + if (debuginfod_so == NULL) + debuginfod_so = dlopen("libdebuginfod.so", RTLD_LAZY); + if (debuginfod_so != NULL) + fp_debuginfod_find_executable = dlsym (debuginfod_so, "debuginfod_find_executable"); + if (fp_debuginfod_find_executable == NULL) + fp_debuginfod_find_executable = (void *) -1; /* never try again */ + } + + if (fp_debuginfod_find_executable != NULL && fp_debuginfod_find_executable != (void *) -1) + { + /* If all else fails and a build-id is available, query the + debuginfo-server if enabled. */ + if (fd < 0 && mod->build_id_len > 0) + fd = (*fp_debuginfod_find_executable) (mod->build_id_bits, + mod->build_id_len, + NULL); + } + } + + if (fd < 0 && errno == 0 && mod->build_id_len > 0) /* Setting this with no file yet loaded is a marker that the build ID is authoritative even if we also know a putative *FILE_NAME. */ diff --git a/libdwfl/find-debuginfo.c b/libdwfl/find-debuginfo.c index 9267788d..ffc07f92 100644 --- a/libdwfl/find-debuginfo.c +++ b/libdwfl/find-debuginfo.c @@ -1,5 +1,5 @@ /* Standard find_debuginfo callback for libdwfl. - Copyright (C) 2005-2010, 2014, 2015 Red Hat, Inc. + Copyright (C) 2005-2010, 2014, 2015, 2019 Red Hat, Inc. This file is part of elfutils. This file is free software; you can redistribute it and/or modify @@ -31,9 +31,11 @@ #endif #include "libdwflP.h" +#include "debuginfod.h" #include #include #include +#include #include #include "system.h" @@ -359,7 +361,8 @@ dwfl_standard_find_debuginfo (Dwfl_Module *mod, other than just by finding nothing, that's all we do. */ const unsigned char *bits; GElf_Addr vaddr; - if (INTUSE(dwfl_module_build_id) (mod, &bits, &vaddr) > 0) + int bits_len; + if ((bits_len = INTUSE(dwfl_module_build_id) (mod, &bits, &vaddr)) > 0) { /* Dropping most arguments means we cannot rely on them in dwfl_build_id_find_debuginfo. But leave it that way since @@ -397,6 +400,30 @@ dwfl_standard_find_debuginfo (Dwfl_Module *mod, free (canon); } + { + /* NB: this is slightly thread-unsafe */ + static __typeof__ (debuginfod_find_debuginfo) *fp_debuginfod_find_debuginfo; + + if (fp_debuginfod_find_debuginfo == NULL) + { + void *debuginfod_so = dlopen("libdebuginfod-" VERSION ".so", RTLD_LAZY); + if (debuginfod_so == NULL) + debuginfod_so = dlopen("libdebuginfod.so", RTLD_LAZY); + if (debuginfod_so != NULL) + fp_debuginfod_find_debuginfo = dlsym (debuginfod_so, "debuginfod_find_debuginfo"); + if (fp_debuginfod_find_debuginfo == NULL) + fp_debuginfod_find_debuginfo = (void *) -1; /* never try again */ + } + + if (fp_debuginfod_find_debuginfo != NULL && fp_debuginfod_find_debuginfo != (void *) -1) + { + /* If all else fails and a build-id is available, query the + debuginfo-server if enabled. */ + if (fd < 0 && bits_len > 0) + fd = (*fp_debuginfod_find_debuginfo) (bits, bits_len, NULL); + } + } + return fd; } INTDEF (dwfl_standard_find_debuginfo) diff --git a/m4/ChangeLog b/m4/ChangeLog index 9ee06d75..8ab0ff39 100644 --- a/m4/ChangeLog +++ b/m4/ChangeLog @@ -1,3 +1,7 @@ +2019-10-28 Aaron Merey + + * ax_check_compile_flag.m4, ax_cxx_compile_stdcxx.m4: New files. + 2015-05-01 Mark Wielaard * zip.m4: Explicitly set with_ to no, if not yes. diff --git a/m4/Makefile.am b/m4/Makefile.am index 3b0e1145..ae7a5657 100644 --- a/m4/Makefile.am +++ b/m4/Makefile.am @@ -18,4 +18,4 @@ ## ##m4-files-begin -EXTRA_DIST = codeset.m4 gettext.m4 iconv.m4 lcmessage.m4 progtest.m4 zip.m4 +EXTRA_DIST = codeset.m4 gettext.m4 iconv.m4 lcmessage.m4 progtest.m4 zip.m4 ax_check_compile_flag.m4 ax_cxx_compile_stdcxx.m4 diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4 new file mode 100644 index 00000000..ca363971 --- /dev/null +++ b/m4/ax_check_compile_flag.m4 @@ -0,0 +1,74 @@ +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT]) +# +# DESCRIPTION +# +# Check whether the given FLAG works with the current language's compiler +# or gives an error. (Warnings, however, are ignored) +# +# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on +# success/failure. +# +# If EXTRA-FLAGS is defined, it is added to the current language's default +# flags (e.g. CFLAGS) when the check is done. The check is thus made with +# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to +# force the compiler to issue an error when a bad flag is given. +# +# INPUT gives an alternative input source to AC_COMPILE_IFELSE. +# +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this +# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG. +# +# LICENSE +# +# Copyright (c) 2008 Guido U. Draheim +# Copyright (c) 2011 Maarten Bosmans +# +# This program 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 of the License, 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. If not, see . +# +# As a special exception, the respective Autoconf Macro's copyright owner +# gives unlimited permission to copy, distribute and modify the configure +# scripts that are the output of Autoconf when processing the Macro. You +# need not follow the terms of the GNU General Public License when using +# or distributing such scripts, even though portions of the text of the +# Macro appear in them. The GNU General Public License (GPL) does govern +# all other use of the material that constitutes the Autoconf Macro. +# +# This special exception to the GPL applies to versions of the Autoconf +# Macro released by the Autoconf Archive. When you make and distribute a +# modified version of the Autoconf Macro, you may extend this special +# exception to the GPL to apply to your modified version as well. + +#serial 4 + +AC_DEFUN([AX_CHECK_COMPILE_FLAG], +[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl +AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [ + ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1" + AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], + [AS_VAR_SET(CACHEVAR,[yes])], + [AS_VAR_SET(CACHEVAR,[no])]) + _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags]) +AS_VAR_IF(CACHEVAR,yes, + [m4_default([$2], :)], + [m4_default([$3], :)]) +AS_VAR_POPDEF([CACHEVAR])dnl +])dnl AX_CHECK_COMPILE_FLAGS diff --git a/m4/ax_cxx_compile_stdcxx.m4 b/m4/ax_cxx_compile_stdcxx.m4 new file mode 100644 index 00000000..8adc7656 --- /dev/null +++ b/m4/ax_cxx_compile_stdcxx.m4 @@ -0,0 +1,556 @@ +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CXX_COMPILE_STDCXX(VERSION, [ext|noext], [mandatory|optional]) +# +# DESCRIPTION +# +# Check for baseline language coverage in the compiler for the specified +# version of the C++ standard. If necessary, add switches to CXX to +# enable support. VERSION may be '11' (for the C++11 standard) or '14' +# (for the C++14 standard). +# +# The second argument, if specified, indicates whether you insist on an +# extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g. +# -std=c++11). If neither is specified, you get whatever works, with +# preference for an extended mode. +# +# The third argument, if specified 'mandatory' or if left unspecified, +# indicates that baseline support for the specified C++ standard is +# required and that the macro should error out if no mode with that +# support is found. If specified 'optional', then configuration proceeds +# regardless, after defining HAVE_CXX${VERSION} if and only if a +# supporting mode is found. +# +# LICENSE +# +# Copyright (c) 2008 Benjamin Kosnik +# Copyright (c) 2012 Zack Weinberg +# Copyright (c) 2013 Roy Stogner +# Copyright (c) 2014, 2015 Google Inc.; contributed by Alexey Sokolov +# Copyright (c) 2015 Paul Norman +# Copyright (c) 2015 Moritz Klammler +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. This file is offered as-is, without any +# warranty. + +#serial 3 + +dnl This macro is based on the code from the AX_CXX_COMPILE_STDCXX_11 macro +dnl (serial version number 13). + +AC_DEFUN([AX_CXX_COMPILE_STDCXX], [dnl + m4_if([$1], [11], [], + [$1], [14], [], + [$1], [17], [m4_fatal([support for C++17 not yet implemented in AX_CXX_COMPILE_STDCXX])], + [m4_fatal([invalid first argument `$1' to AX_CXX_COMPILE_STDCXX])])dnl + m4_if([$2], [], [], + [$2], [ext], [], + [$2], [noext], [], + [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX])])dnl + m4_if([$3], [], [ax_cxx_compile_cxx$1_required=true], + [$3], [mandatory], [ax_cxx_compile_cxx$1_required=true], + [$3], [optional], [ax_cxx_compile_cxx$1_required=false], + [m4_fatal([invalid third argument `$3' to AX_CXX_COMPILE_STDCXX])]) + AC_LANG_PUSH([C++])dnl + ac_success=no + AC_CACHE_CHECK(whether $CXX supports C++$1 features by default, + ax_cv_cxx_compile_cxx$1, + [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], + [ax_cv_cxx_compile_cxx$1=yes], + [ax_cv_cxx_compile_cxx$1=no])]) + if test x$ax_cv_cxx_compile_cxx$1 = xyes; then + ac_success=yes + fi + + m4_if([$2], [noext], [], [dnl + if test x$ac_success = xno; then + for switch in -std=gnu++$1 -std=gnu++0x; do + cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch]) + AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch, + $cachevar, + [ac_save_CXX="$CXX" + CXX="$CXX $switch" + AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], + [eval $cachevar=yes], + [eval $cachevar=no]) + CXX="$ac_save_CXX"]) + if eval test x\$$cachevar = xyes; then + CXX="$CXX $switch" + ac_success=yes + break + fi + done + fi]) + + m4_if([$2], [ext], [], [dnl + if test x$ac_success = xno; then + dnl HP's aCC needs +std=c++11 according to: + dnl http://h21007.www2.hp.com/portal/download/files/unprot/aCxx/PDF_Release_Notes/769149-001.pdf + dnl Cray's crayCC needs "-h std=c++11" + for switch in -std=c++$1 -std=c++0x +std=c++$1 "-h std=c++$1"; do + cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx$1_$switch]) + AC_CACHE_CHECK(whether $CXX supports C++$1 features with $switch, + $cachevar, + [ac_save_CXX="$CXX" + CXX="$CXX $switch" + AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_testbody_$1])], + [eval $cachevar=yes], + [eval $cachevar=no]) + CXX="$ac_save_CXX"]) + if eval test x\$$cachevar = xyes; then + CXX="$CXX $switch" + ac_success=yes + break + fi + done + fi]) + AC_LANG_POP([C++]) + if test x$ax_cxx_compile_cxx$1_required = xtrue; then + if test x$ac_success = xno; then + AC_MSG_ERROR([*** A compiler with support for C++$1 language features is required.]) + fi + fi + if test x$ac_success = xno; then + HAVE_CXX$1=0 + AC_MSG_NOTICE([No compiler with C++$1 support was found]) + else + HAVE_CXX$1=1 + AC_DEFINE(HAVE_CXX$1,1, + [define if the compiler supports basic C++$1 syntax]) + fi + AC_SUBST(HAVE_CXX$1) +]) + + +dnl Test body for checking C++11 support + +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_11], + _AX_CXX_COMPILE_STDCXX_testbody_new_in_11 +) + + +dnl Test body for checking C++14 support + +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_14], + _AX_CXX_COMPILE_STDCXX_testbody_new_in_11 + _AX_CXX_COMPILE_STDCXX_testbody_new_in_14 +) + + +dnl Tests for new features in C++11 + +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_11], [[ + +// If the compiler admits that it is not ready for C++11, why torture it? +// Hopefully, this will speed up the test. + +#ifndef __cplusplus + +#error "This is not a C++ compiler" + +#elif __cplusplus < 201103L + +#error "This is not a C++11 compiler" + +#else + +namespace cxx11 +{ + + namespace test_static_assert + { + + template + struct check + { + static_assert(sizeof(int) <= sizeof(T), "not big enough"); + }; + + } + + namespace test_final_override + { + + struct Base + { + virtual void f() {} + }; + + struct Derived : public Base + { + virtual void f() override {} + }; + + } + + namespace test_double_right_angle_brackets + { + + template < typename T > + struct check {}; + + typedef check single_type; + typedef check> double_type; + typedef check>> triple_type; + typedef check>>> quadruple_type; + + } + + namespace test_decltype + { + + int + f() + { + int a = 1; + decltype(a) b = 2; + return a + b; + } + + } + + namespace test_type_deduction + { + + template < typename T1, typename T2 > + struct is_same + { + static const bool value = false; + }; + + template < typename T > + struct is_same + { + static const bool value = true; + }; + + template < typename T1, typename T2 > + auto + add(T1 a1, T2 a2) -> decltype(a1 + a2) + { + return a1 + a2; + } + + int + test(const int c, volatile int v) + { + static_assert(is_same::value == true, ""); + static_assert(is_same::value == false, ""); + static_assert(is_same::value == false, ""); + auto ac = c; + auto av = v; + auto sumi = ac + av + 'x'; + auto sumf = ac + av + 1.0; + static_assert(is_same::value == true, ""); + static_assert(is_same::value == true, ""); + static_assert(is_same::value == true, ""); + static_assert(is_same::value == false, ""); + static_assert(is_same::value == true, ""); + return (sumf > 0.0) ? sumi : add(c, v); + } + + } + + namespace test_noexcept + { + + int f() { return 0; } + int g() noexcept { return 0; } + + static_assert(noexcept(f()) == false, ""); + static_assert(noexcept(g()) == true, ""); + + } + + namespace test_constexpr + { + + template < typename CharT > + unsigned long constexpr + strlen_c_r(const CharT *const s, const unsigned long acc) noexcept + { + return *s ? strlen_c_r(s + 1, acc + 1) : acc; + } + + template < typename CharT > + unsigned long constexpr + strlen_c(const CharT *const s) noexcept + { + return strlen_c_r(s, 0UL); + } + + static_assert(strlen_c("") == 0UL, ""); + static_assert(strlen_c("1") == 1UL, ""); + static_assert(strlen_c("example") == 7UL, ""); + static_assert(strlen_c("another\0example") == 7UL, ""); + + } + + namespace test_rvalue_references + { + + template < int N > + struct answer + { + static constexpr int value = N; + }; + + answer<1> f(int&) { return answer<1>(); } + answer<2> f(const int&) { return answer<2>(); } + answer<3> f(int&&) { return answer<3>(); } + + void + test() + { + int i = 0; + const int c = 0; + static_assert(decltype(f(i))::value == 1, ""); + static_assert(decltype(f(c))::value == 2, ""); + static_assert(decltype(f(0))::value == 3, ""); + } + + } + + namespace test_uniform_initialization + { + + struct test + { + static const int zero {}; + static const int one {1}; + }; + + static_assert(test::zero == 0, ""); + static_assert(test::one == 1, ""); + + } + + namespace test_lambdas + { + + void + test1() + { + auto lambda1 = [](){}; + auto lambda2 = lambda1; + lambda1(); + lambda2(); + } + + int + test2() + { + auto a = [](int i, int j){ return i + j; }(1, 2); + auto b = []() -> int { return '0'; }(); + auto c = [=](){ return a + b; }(); + auto d = [&](){ return c; }(); + auto e = [a, &b](int x) mutable { + const auto identity = [](int y){ return y; }; + for (auto i = 0; i < a; ++i) + a += b--; + return x + identity(a + b); + }(0); + return a + b + c + d + e; + } + + int + test3() + { + const auto nullary = [](){ return 0; }; + const auto unary = [](int x){ return x; }; + using nullary_t = decltype(nullary); + using unary_t = decltype(unary); + const auto higher1st = [](nullary_t f){ return f(); }; + const auto higher2nd = [unary](nullary_t f1){ + return [unary, f1](unary_t f2){ return f2(unary(f1())); }; + }; + return higher1st(nullary) + higher2nd(nullary)(unary); + } + + } + + namespace test_variadic_templates + { + + template + struct sum; + + template + struct sum + { + static constexpr auto value = N0 + sum::value; + }; + + template <> + struct sum<> + { + static constexpr auto value = 0; + }; + + static_assert(sum<>::value == 0, ""); + static_assert(sum<1>::value == 1, ""); + static_assert(sum<23>::value == 23, ""); + static_assert(sum<1, 2>::value == 3, ""); + static_assert(sum<5, 5, 11>::value == 21, ""); + static_assert(sum<2, 3, 5, 7, 11, 13>::value == 41, ""); + + } + + // http://stackoverflow.com/questions/13728184/template-aliases-and-sfinae + // Clang 3.1 fails with headers of libstd++ 4.8.3 when using std::function + // because of this. + namespace test_template_alias_sfinae + { + + struct foo {}; + + template + using member = typename T::member_type; + + template + void func(...) {} + + template + void func(member*) {} + + void test(); + + void test() { func(0); } + + } + +} // namespace cxx11 + +#endif // __cplusplus >= 201103L + +]]) + + +dnl Tests for new features in C++14 + +m4_define([_AX_CXX_COMPILE_STDCXX_testbody_new_in_14], [[ + +// If the compiler admits that it is not ready for C++14, why torture it? +// Hopefully, this will speed up the test. + +#ifndef __cplusplus + +#error "This is not a C++ compiler" + +#elif __cplusplus < 201402L + +#error "This is not a C++14 compiler" + +#else + +namespace cxx14 +{ + + namespace test_polymorphic_lambdas + { + + int + test() + { + const auto lambda = [](auto&&... args){ + const auto istiny = [](auto x){ + return (sizeof(x) == 1UL) ? 1 : 0; + }; + const int aretiny[] = { istiny(args)... }; + return aretiny[0]; + }; + return lambda(1, 1L, 1.0f, '1'); + } + + } + + namespace test_binary_literals + { + + constexpr auto ivii = 0b0000000000101010; + static_assert(ivii == 42, "wrong value"); + + } + + namespace test_generalized_constexpr + { + + template < typename CharT > + constexpr unsigned long + strlen_c(const CharT *const s) noexcept + { + auto length = 0UL; + for (auto p = s; *p; ++p) + ++length; + return length; + } + + static_assert(strlen_c("") == 0UL, ""); + static_assert(strlen_c("x") == 1UL, ""); + static_assert(strlen_c("test") == 4UL, ""); + static_assert(strlen_c("another\0test") == 7UL, ""); + + } + + namespace test_lambda_init_capture + { + + int + test() + { + auto x = 0; + const auto lambda1 = [a = x](int b){ return a + b; }; + const auto lambda2 = [a = lambda1(x)](){ return a; }; + return lambda2(); + } + + } + + namespace test_digit_seperators + { + + constexpr auto ten_million = 100'000'000; + static_assert(ten_million == 100000000, ""); + + } + + namespace test_return_type_deduction + { + + auto f(int& x) { return x; } + decltype(auto) g(int& x) { return x; } + + template < typename T1, typename T2 > + struct is_same + { + static constexpr auto value = false; + }; + + template < typename T > + struct is_same + { + static constexpr auto value = true; + }; + + int + test() + { + auto x = 0; + static_assert(is_same::value, ""); + static_assert(is_same::value, ""); + return x; + } + + } + +} // namespace cxx14 + +#endif // __cplusplus >= 201402L + +]]) -- cgit v1.2.3