From 57cefb5932f5a757d2164021344c3a3ab4a24b85 Mon Sep 17 00:00:00 2001 From: Mathieu Duponchelle Date: Fri, 25 Jan 2019 02:36:18 +0100 Subject: [PATCH] gstinfo: add Windows stacktraces support This uses the DbgHelp library if available --- gst/gstinfo.c | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++++- meson.build | 13 +++---- meson_options.txt | 1 + 3 files changed, 111 insertions(+), 7 deletions(-) diff --git a/gst/gstinfo.c b/gst/gstinfo.c index 2dcf04d..f3ae152 100644 --- a/gst/gstinfo.c +++ b/gst/gstinfo.c @@ -155,6 +155,12 @@ static char *gst_info_printf_pointer_extension_func (const char *format, #define BT_BUF_SIZE 100 #endif /* HAVE_BACKTRACE */ +#ifdef HAVE_DBGHELP +#include +#include +#include +#endif /* HAVE_DBGHELP */ + extern gboolean gst_is_initialized (void); /* we want these symbols exported even if debug is disabled, to maintain @@ -2763,6 +2769,98 @@ generate_backtrace_trace (void) #define generate_backtrace_trace() NULL #endif /* HAVE_BACKTRACE */ +#ifdef HAVE_DBGHELP +static void +dbghelp_initialize_symbols (HANDLE process) +{ + static gsize initialization_value = 0; + + if (g_once_init_enter (&initialization_value)) { + GST_INFO ("Initializing Windows symbol handler"); + SymSetOptions (SYMOPT_LOAD_LINES); + SymInitialize (process, NULL, TRUE); + GST_INFO ("Initialized Windows symbol handler"); + + g_once_init_leave (&initialization_value, 1); + } +} + +static gchar * +generate_dbghelp_trace (void) +{ + HANDLE process = GetCurrentProcess (); + HANDLE thread = GetCurrentThread (); + IMAGEHLP_MODULE64 module_info; + DWORD machine; + CONTEXT context; + STACKFRAME64 frame = { 0 }; + PVOID save_context; + GString *trace = g_string_new (NULL); + + dbghelp_initialize_symbols (process); + + memset (&context, 0, sizeof (CONTEXT)); + context.ContextFlags = CONTEXT_FULL; + + RtlCaptureContext (&context); + + frame.AddrPC.Mode = AddrModeFlat; + frame.AddrStack.Mode = AddrModeFlat; + frame.AddrFrame.Mode = AddrModeFlat; + +#if (defined _M_IX86) + machine = IMAGE_FILE_MACHINE_I386; + frame.AddrFrame.Offset = context.Ebp; + frame.AddrPC.Offset = context.Eip; + frame.AddrStack.Offset = context.Esp; +#elif (defined _M_X64) + machine = IMAGE_FILE_MACHINE_AMD64; + frame.AddrFrame.Offset = context.Rbp; + frame.AddrPC.Offset = context.Rip; + frame.AddrStack.Offset = context.Rsp; +#else + goto done; +#endif + + module_info.SizeOfStruct = sizeof (module_info); + save_context = (machine == IMAGE_FILE_MACHINE_I386) ? NULL : &context; + + while (TRUE) { + char buffer[sizeof (SYMBOL_INFO) + MAX_SYM_NAME * sizeof (TCHAR)]; + PSYMBOL_INFO symbol = (PSYMBOL_INFO) buffer; + IMAGEHLP_LINE64 line; + DWORD displacement = 0; + + symbol->SizeOfStruct = sizeof (SYMBOL_INFO); + symbol->MaxNameLen = MAX_SYM_NAME; + + line.SizeOfStruct = sizeof (line); + + if (!StackWalk64 (machine, process, thread, &frame, save_context, 0, + SymFunctionTableAccess64, SymGetModuleBase64, 0)) + break; + + if (SymFromAddr (process, frame.AddrPC.Offset, 0, symbol)) + g_string_append_printf (trace, "%s ", symbol->Name); + else + g_string_append (trace, "?? "); + + if (SymGetLineFromAddr64 (process, frame.AddrPC.Offset, &displacement, + &line)) + g_string_append_printf (trace, "(%s:%u)", line.FileName, line.LineNumber); + else if (SymGetModuleInfo64 (process, frame.AddrPC.Offset, &module_info)) + g_string_append_printf (trace, "(%s)", module_info.ImageName); + else + g_string_append_printf (trace, "(%s)", "??"); + + g_string_append (trace, "\n"); + } + +done: + return g_string_free (trace, FALSE); +} +#endif /* HAVE_DBGHELP */ + /** * gst_debug_get_stack_trace: * @flags: A set of #GstStackTraceFlags to determine how the stack @@ -2788,6 +2886,10 @@ gst_debug_get_stack_trace (GstStackTraceFlags flags) trace = generate_unwind_trace (flags); #endif /* HAVE_UNWIND */ +#ifdef HAVE_DBGHELP + trace = generate_dbghelp_trace (); +#endif + if (trace) return trace; else if (have_backtrace) @@ -2799,7 +2901,7 @@ gst_debug_get_stack_trace (GstStackTraceFlags flags) /** * gst_debug_print_stack_trace: * - * If libunwind or glibc backtrace are present + * If libunwind, glibc backtrace or DbgHelp are present * a stack trace is printed. */ void diff --git a/meson.build b/meson.build index 6622049..f1d54ca 100644 --- a/meson.build +++ b/meson.build @@ -348,7 +348,8 @@ endif backtrace_deps = [] unwind_dep = dependency('libunwind', required : get_option('libunwind')) dw_dep = dependency('libdw', required: get_option('libdw')) -backtrace_deps = [unwind_dep, dw_dep] +dbghelp_dep = dependency('DbgHelp', required : get_option('dbghelp')) +backtrace_deps = [unwind_dep, dw_dep, dbghelp_dep] if unwind_dep.found() cdata.set('HAVE_UNWIND', 1) if dw_dep.found() @@ -356,12 +357,12 @@ if unwind_dep.found() else message('Support for backtraces is partial only.') endif +elif cc.has_function('backtrace') + cdata.set('HAVE_BACKTRACE', 1) +elif dbghelp_dep.found() + cdata.set('HAVE_DBGHELP', 1) else - if cc.has_function('backtrace') - cdata.set('HAVE_BACKTRACE', 1) - else - message('NO backtraces support.') - endif + message('NO backtraces support.') endif if cc.has_header('execinfo.h') diff --git a/meson_options.txt b/meson_options.txt index 50445af..e7ff7ba 100644 --- a/meson_options.txt +++ b/meson_options.txt @@ -21,6 +21,7 @@ option('memory-alignment', type: 'combo', option('check', type : 'feature', value : 'auto', description : 'Build unit test libraries') option('libunwind', type : 'feature', value : 'auto', description : 'Use libunwind to generate backtraces') option('libdw', type : 'feature', value : 'auto', description : 'Use libdw to generate better backtraces from libunwind') +option('dbghelp', type : 'feature', value : 'auto', description : 'Use dbghelp to generate backtraces') option('bash-completion', type : 'feature', value : 'auto', description : 'Install bash completion files') # Common feature options -- 2.7.4