support stack unwinding on assert via Unwind

Signed-off-by: Ivailo Monev <xakepa10@laimg.moc>

.travis.yml

@@ -13,7 +13,7 @@ services:
     - xvfb
 before_install:
     - sudo apt-get update -qq
-    - sudo apt-get install -qq ninja-build libpcre3-dev libssl-dev zlib1g-dev libc6-dev libpng-dev libjpeg-dev libtiff-dev libmng-dev libcups2-dev libfreetype6-dev libfontconfig1-dev libdbus-1-dev libicu-dev unixodbc-dev libpq-dev libpqtypes-dev libmysqld-dev libaio-dev libwrap0-dev liblz4-dev libsqlite3-dev xorg-dev
+    - sudo apt-get install -qq ninja-build libpcre3-dev libssl-dev zlib1g-dev libc6-dev libpng-dev libjpeg-dev libtiff-dev libmng-dev libcups2-dev libfreetype6-dev libfontconfig1-dev libdbus-1-dev libicu-dev unixodbc-dev libpq-dev libpqtypes-dev libmysqld-dev libaio-dev libwrap0-dev liblz4-dev libsqlite3-dev libunwind-dev xorg-dev
     - wget 'http://mirrors.kernel.org/ubuntu/pool/universe/libz/libzstd/libzstd1_1.3.1+dfsg-1~ubuntu0.16.04.1_amd64.deb'
     - wget 'http://mirrors.kernel.org/ubuntu/pool/universe/libz/libzstd/libzstd1-dev_1.3.1+dfsg-1~ubuntu0.16.04.1_amd64.deb'
     - sudo dpkg -i *.deb

CMakeLists.txt

@@ -60,6 +60,7 @@ if(NOT CMAKE_VERSION VERSION_LESS "3.3.0")
 endif()
 
 include(CheckIncludeFile)
+include(CheckIncludeFileCXX)
 include(CheckTypeSize)
 include(FeatureSummary)
 include(KatieMacros)
@@ -156,6 +157,9 @@ add_feature_info(resolv WITH_RESOLV "build resolv support")
 option(WITH_NSL "Build NSL support" ON)
 add_feature_info(nsl WITH_NSL "build NSL support")
 
+option(WITH_UNWIND "Build Unwind support" ON)
+add_feature_info(unwind WITH_UNWIND "build Unwind support")
+
 # optional features
 option(KATIE_TESTS "Build automatic tests" OFF)
 add_feature_info(tests KATIE_TESTS "build automatic tests")
@@ -203,6 +207,9 @@ if(KATIE_ALLINONE)
     add_definitions(-DQT_ALLINONE)
 endif()
 
+# for symbols mangling while unwinding in core component
+check_include_file_cxx(cxxabi.h HAVE_CXXABI)
+
 # for 3rd party source used in test component
 check_include_file(sys/time.h HAVE_SYS_TIME_H)
 
@@ -426,6 +433,14 @@ set_package_properties(MySQL PROPERTIES
     TYPE OPTIONAL
 )
 
+find_package(Unwind)
+set_package_properties(Unwind PROPERTIES
+    PURPOSE "Required for stack traces on assert"
+    DESCRIPTION "A (mostly) platform-independent unwind API"
+    URL "https://www.nongnu.org/libunwind/index.html"
+    TYPE OPTIONAL
+)
+
 if(KATIE_TESTS OR KATIE_BENCHMARKS)
     message(WARNING
         "\nUnless it is intentionall you should not enable testing, deploying tests builds"
@@ -494,6 +509,10 @@ if(NOT WITH_TIFF OR NOT TIFF_FOUND)
     katie_definition(-DQT_NO_IMAGEFORMAT_TIFF)
 endif()
 
+if(NOT WITH_UNWIND OR NOT UNWIND_FOUND OR NOT HAVE_CXXABI)
+    katie_definition(-DQT_NO_UNWIND)
+endif()
+
 # conditional features
 if(NOT WITH_ACCESSIBILITY)
     katie_definition(-DQT_NO_ACCESSIBILITY)

cmake/modules/FindUnwind.cmake

@@ -0,0 +1,44 @@
+# - Try to find Unwind
+# Once done this will define
+#
+#  UNWIND_FOUND - system has Unwind
+#  UNWIND_INCLUDES - the Unwind include directory
+#  UNWIND_LIBRARIES - the libraries needed to use Unwind
+#
+# Copyright (c) 2015-2019, Ivailo Monev, <xakepa10@gmail.com>
+#
+# Redistribution and use is allowed according to the terms of the BSD license.
+
+if(UNWIND_INCLUDES AND UNWIND_LIBRARIES)
+    set(UNWIND_FIND_QUIETLY TRUE)
+endif()
+
+if(NOT WIN32)
+    include(FindPkgConfig)
+    pkg_check_modules(PC_UNWIND QUIET libunwind)
+endif()
+
+find_path(UNWIND_INCLUDES
+    NAMES
+    libunwind.h
+    HINTS
+    $ENV{UNWINDDIR}/include
+    ${PC_UNWIND_INCLUDEDIR}
+    ${INCLUDE_INSTALL_DIR}
+)
+
+find_library(UNWIND_LIBRARIES
+    unwind
+    HINTS
+    $ENV{UNWINDDIR}/lib
+    ${PC_UNWIND_LIBDIR}
+    ${LIB_INSTALL_DIR}
+)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Unwind
+    VERSION_VAR PC_UNWIND_VERSION
+    REQUIRED_VARS UNWIND_LIBRARIES UNWIND_INCLUDES
+)
+
+mark_as_advanced(UNWIND_INCLUDES UNWIND_LIBRARIES)

package/archlinux/PKGBUILD

@@ -10,7 +10,7 @@ url='https://github.com/fluxer/katie'
 license=('LGPL' 'FDL' 'custom')
 depends=('openssl' 'zlib' 'cups' 'libice' 'libsm' 'pcre' 'libxcursor' 'icu'
         'libxext' 'libxfixes' 'libxi' 'libxinerama' 'libxrandr' 'libxrender'
-        'libx11' 'fontconfig' 'freetype2' 'libmng' 'zstd')
+        'libx11' 'fontconfig' 'freetype2' 'libmng' 'zstd' 'libunwind')
 makedepends=('cmake' 'git' 'postgresql' 'libmariadbclient' 'unixodbc' 'unifdef')
 optdepends=('postgresql-libs: PostgreSQL driver'
         'libmariadbclient: MariaDB driver'

package/debian/control

@@ -10,12 +10,13 @@ Build-Depends: debhelper (>= 9~), g++, libssl-dev, zlib1g-dev, libzstd-dev,
  libc6-dev, libpng-dev, libjpeg-dev, libtiff5-dev, libmng-dev, libcups2-dev,
  libfreetype6-dev, libfontconfig1-dev, libpcre3-dev, libdbus-1-dev,
  unixodbc-dev, libpq-dev, libpqtypes-dev, libmariadbclient-dev, libicu-dev,
- libmariadbd-dev, libaio-dev, libsqlite3-dev, xorg-dev, cmake, git
+ libmariadbd-dev, libaio-dev, libsqlite3-dev, xorg-dev, cmake, git,
+ libunwind-dev
 
 Package: katie-git
 Architecture: i386 amd64
 Depends: ${shlibs:Depends}, ${misc:Depends}, openssl, zlib1g, libzstd1, libc6,
  libpng16-16, libjpeg62-turbo, libtiffxx5, libmng1, libcups2, libfreetype6,
- libfontconfig1, libpcre3,  libdbus-1-3, libsqlite3-0, libicu63
+ libfontconfig1, libpcre3,  libdbus-1-3, libsqlite3-0, libicu63, libunwind8
 Recommends: unixodbc, libpq5, libmariadbclient, xorg
 Description: C++ toolkit derived from the Qt 4.8 framework

src/core/CMakeLists.txt

@@ -259,6 +259,15 @@ if(WITH_THREADS AND THREADS_FOUND)
     )
 endif()
 
+if(WITH_UNWIND AND UNWIND_FOUND AND HAVE_CXXABI)
+    set(EXTRA_CORE_LIBS
+        ${EXTRA_CORE_LIBS}
+        ${UNWIND_LIBRARIES}
+    )
+    include_directories(${UNWIND_INCLUDES})
+endif()
+     
+
 set(CORE_HEADERS
     ${CORE_HEADERS}
     ${CMAKE_CURRENT_SOURCE_DIR}/qcorecommon_p.h

src/core/global/qconfig.h.cmake

@@ -321,6 +321,7 @@
 #cmakedefine QT_NO_UNDOSTACK
 #cmakedefine QT_NO_UNDOVIEW
 #cmakedefine QT_NO_UNSETENV
+#cmakedefine QT_NO_UNWIND
 #cmakedefine QT_NO_URLINFO
 #cmakedefine QT_NO_URL_CAST_FROM_STRING
 #cmakedefine QT_NO_VALIDATOR

src/core/global/qglobal.cpp

@@ -56,6 +56,12 @@
 #  include <exception>
 #endif
 
+#ifndef QT_NO_UNWIND
+#  define UNW_LOCAL_ONLY
+#  include <libunwind.h>
+#  include <cxxabi.h>
+#endif
+
 QT_BEGIN_NAMESPACE
 
 
@@ -1352,11 +1358,42 @@ void qBadAlloc()
     QT_THROW(std::bad_alloc());
 }
 
+static inline void qt_print_backtrace()
+{
+#ifndef QT_NO_UNWIND
+    unw_cursor_t cursor;
+    unw_context_t context;
+
+    unw_getcontext(&context);
+    unw_init_local(&cursor, &context);
+
+    while (unw_step(&cursor) > 0) {
+        unw_word_t offset;
+        char sym[256];
+        if (unw_get_proc_name(&cursor, sym, sizeof(sym), &offset) == 0) {
+            int status;
+            char* demangled = abi::__cxa_demangle(sym, nullptr, nullptr, &status);
+            if (status == 0) {
+                printf(" %s\n", demangled);
+                free(demangled);
+            } else {
+                printf(" %s\n", sym);
+            }
+            
+            
+        } else {
+            printf("qt_print_backtrace: unable to obtain symbol name for this frame\n");
+        }
+    }
+#endif
+}
+
 /*
   The Q_ASSERT macro calls this function when the test fails.
 */
 void qt_assert(const char *assertion, const char *file, int line)
 {
+    qt_print_backtrace();
     qFatal("ASSERT: \"%s\" in file %s, line %d", assertion, file, line);
 }
 
@@ -1365,6 +1402,7 @@ void qt_assert(const char *assertion, const char *file, int line)
 */
 void qt_assert_x(const char *where, const char *what, const char *file, int line)
 {
+    qt_print_backtrace();
     qFatal("ASSERT failure in %s: \"%s\", file %s, line %d", where, what, file, line);
 }
 

src/tools/moc/CMakeLists.txt

@@ -39,6 +39,7 @@ set(BOOTSTRAP_DEFINITIONS
     -DQT_NO_COMPRESS
     -DQT_NO_EXCEPTIONS
     -DQT_NO_REGEXP
+    -DQT_NO_UNWIND
 )
 
 set(BOOTSTRAP_SOURCES