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-rw-r--r--mysys/stacktrace.c735
1 files changed, 735 insertions, 0 deletions
diff --git a/mysys/stacktrace.c b/mysys/stacktrace.c
new file mode 100644
index 00000000..5718b2e7
--- /dev/null
+++ b/mysys/stacktrace.c
@@ -0,0 +1,735 @@
+/*
+ Copyright (c) 2001, 2011, Oracle and/or its affiliates
+ Copyright (c) 2020, MariaDB Corporation.
+
+ 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; version 2 of the License.
+
+ 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, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
+
+#include "mysys_priv.h"
+#include <my_stacktrace.h>
+
+#ifndef __WIN__
+#include <signal.h>
+#include <m_string.h>
+#ifdef HAVE_STACKTRACE
+#include <unistd.h>
+#include <strings.h>
+
+#ifdef __linux__
+#include <ctype.h> /* isprint */
+#include <sys/syscall.h> /* SYS_gettid */
+#endif
+
+#if HAVE_EXECINFO_H
+#include <execinfo.h>
+#endif
+
+/**
+ Default handler for printing stacktrace
+*/
+
+static sig_handler default_handle_fatal_signal(int sig)
+{
+ my_safe_printf_stderr("%s: Got signal %d. Attempting backtrace\n",
+ my_progname_short, sig);
+ my_print_stacktrace(0,0,1);
+#ifndef __WIN__
+ signal(sig, SIG_DFL);
+ kill(getpid(), sig);
+#endif /* __WIN__ */
+ return;
+}
+
+
+/**
+ Initialize priting off stacktrace at signal
+*/
+
+void my_setup_stacktrace(void)
+{
+ struct sigaction sa;
+ sa.sa_flags = SA_RESETHAND | SA_NODEFER;
+ sigemptyset(&sa.sa_mask);
+ sa.sa_handler= default_handle_fatal_signal;
+ sigaction(SIGSEGV, &sa, NULL);
+ sigaction(SIGABRT, &sa, NULL);
+#ifdef SIGBUS
+ sigaction(SIGBUS, &sa, NULL);
+#endif
+ sigaction(SIGILL, &sa, NULL);
+ sigaction(SIGFPE, &sa, NULL);
+}
+
+
+/*
+ Attempt to print a char * pointer as a string.
+
+ SYNOPSIS
+ Prints either until the end of string ('\0'), or max_len characters have
+ been printed.
+
+ RETURN VALUE
+ 0 Pointer was within the heap address space.
+ The string was printed fully, or until the end of the heap address space.
+ 1 Pointer is outside the heap address space. Printed as invalid.
+
+ NOTE
+ On some systems, we can have valid pointers outside the heap address space.
+ This is through the use of mmap inside malloc calls. When this function
+ returns 1, it does not mean 100% that the pointer is corrupted.
+*/
+
+int my_safe_print_str(const char* val, size_t max_len)
+{
+ const char *orig_val= val;
+ if (!val)
+ {
+ my_safe_printf_stderr("%s", "(null)");
+ return 1;
+ }
+
+ for (; max_len; --max_len)
+ {
+ if (my_write_stderr((val++), 1) != 1)
+ {
+ if ((errno == EFAULT) &&(val == orig_val + 1))
+ {
+ // We can not read the address from very beginning
+ my_safe_printf_stderr("Can't access address %p", orig_val);
+ }
+ break;
+ }
+ }
+ my_safe_printf_stderr("%s", "\n");
+
+ return 0;
+}
+
+#if defined(HAVE_PRINTSTACK)
+
+/* Use Solaris' symbolic stack trace routine. */
+#include <ucontext.h>
+
+void my_print_stacktrace(uchar* stack_bottom __attribute__((unused)),
+ ulong thread_stack __attribute__((unused)),
+ my_bool silent)
+{
+ if (printstack(fileno(stderr)) == -1)
+ my_safe_printf_stderr("%s",
+ "Error when traversing the stack, stack appears corrupt.\n");
+ else if (!silent)
+ my_safe_printf_stderr("%s",
+ "Please read "
+ "http://dev.mysql.com/doc/refman/5.1/en/resolve-stack-dump.html\n"
+ "and follow instructions on how to resolve the stack trace.\n"
+ "Resolved stack trace is much more helpful in diagnosing the\n"
+ "problem, so please do resolve it\n");
+}
+
+#elif HAVE_BACKTRACE && (HAVE_BACKTRACE_SYMBOLS || HAVE_BACKTRACE_SYMBOLS_FD)
+
+#if BACKTRACE_DEMANGLE
+
+char __attribute__ ((weak)) *
+my_demangle(const char *mangled_name __attribute__((unused)),
+ int *status __attribute__((unused)))
+{
+ return NULL;
+}
+
+static void my_demangle_symbols(char **addrs, int n)
+{
+ int status, i;
+ char *begin, *end, *demangled;
+
+ for (i= 0; i < n; i++)
+ {
+ demangled= NULL;
+ begin= strchr(addrs[i], '(');
+ end= begin ? strchr(begin, '+') : NULL;
+
+ if (begin && end)
+ {
+ *begin++= *end++= '\0';
+ demangled= my_demangle(begin, &status);
+ if (!demangled || status)
+ {
+ demangled= NULL;
+ begin[-1]= '(';
+ end[-1]= '+';
+ }
+ }
+
+ if (demangled)
+ my_safe_printf_stderr("%s(%s+%s\n", addrs[i], demangled, end);
+ else
+ my_safe_printf_stderr("%s\n", addrs[i]);
+ }
+}
+
+#endif /* BACKTRACE_DEMANGLE */
+
+#if HAVE_MY_ADDR_RESOLVE
+static int print_with_addr_resolve(void **addrs, int n)
+{
+ int i;
+ const char *err;
+
+ if ((err= my_addr_resolve_init()))
+ {
+ my_safe_printf_stderr("(my_addr_resolve failure: %s)\n", err);
+ return 0;
+ }
+
+ for (i= 0; i < n; i++)
+ {
+ my_addr_loc loc;
+ if (my_addr_resolve(addrs[i], &loc))
+ backtrace_symbols_fd(addrs+i, 1, fileno(stderr));
+ else
+ my_safe_printf_stderr("%s:%u(%s)[%p]\n",
+ loc.file, loc.line, loc.func, addrs[i]);
+ }
+ return 1;
+}
+#endif
+
+void my_print_stacktrace(uchar* stack_bottom, ulong thread_stack,
+ my_bool silent __attribute__((unused)))
+{
+ void *addrs[128];
+ char **strings __attribute__((unused)) = NULL;
+ int n = backtrace(addrs, array_elements(addrs));
+ my_safe_printf_stderr("stack_bottom = %p thread_stack 0x%lx\n",
+ stack_bottom, thread_stack);
+#if HAVE_MY_ADDR_RESOLVE
+ if (print_with_addr_resolve(addrs, n))
+ return;
+#endif
+#if BACKTRACE_DEMANGLE
+ if ((strings= backtrace_symbols(addrs, n)))
+ {
+ my_demangle_symbols(strings, n);
+ free(strings);
+ return;
+ }
+#endif
+#if HAVE_BACKTRACE_SYMBOLS_FD
+ backtrace_symbols_fd(addrs, n, fileno(stderr));
+#endif
+}
+
+#elif defined(TARGET_OS_LINUX)
+
+#ifdef __i386__
+#define SIGRETURN_FRAME_OFFSET 17
+#endif
+
+#ifdef __x86_64__
+#define SIGRETURN_FRAME_OFFSET 23
+#endif
+
+#if defined(__alpha__) && defined(__GNUC__)
+/*
+ The only way to backtrace without a symbol table on alpha
+ is to find stq fp,N(sp), and the first byte
+ of the instruction opcode will give us the value of N. From this
+ we can find where the old value of fp is stored
+*/
+
+#define MAX_INSTR_IN_FUNC 10000
+
+inline uchar** find_prev_fp(uint32* pc, uchar** fp)
+{
+ int i;
+ for (i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
+ {
+ uchar* p = (uchar*)pc;
+ if (p[2] == 222 && p[3] == 35)
+ {
+ return (uchar**)((uchar*)fp - *(short int*)p);
+ }
+ }
+ return 0;
+}
+
+inline uint32* find_prev_pc(uint32* pc, uchar** fp)
+{
+ int i;
+ for (i = 0; i < MAX_INSTR_IN_FUNC; ++i,--pc)
+ {
+ char* p = (char*)pc;
+ if (p[1] == 0 && p[2] == 94 && p[3] == -73)
+ {
+ uint32* prev_pc = (uint32*)*((fp+p[0]/sizeof(fp)));
+ return prev_pc;
+ }
+ }
+ return 0;
+}
+#endif /* defined(__alpha__) && defined(__GNUC__) */
+
+void my_print_stacktrace(uchar* stack_bottom, ulong thread_stack,
+ my_bool silent)
+{
+ uchar** UNINIT_VAR(fp);
+ uint frame_count = 0, sigreturn_frame_count;
+#if defined(__alpha__) && defined(__GNUC__)
+ uint32* pc;
+#endif
+
+
+#ifdef __i386__
+ __asm __volatile__ ("movl %%ebp,%0"
+ :"=r"(fp)
+ :"r"(fp));
+#endif
+#ifdef __x86_64__
+ __asm __volatile__ ("movq %%rbp,%0"
+ :"=r"(fp)
+ :"r"(fp));
+#endif
+#if defined(__alpha__) && defined(__GNUC__)
+ __asm __volatile__ ("mov $30,%0"
+ :"=r"(fp)
+ :"r"(fp));
+#endif
+ if (!fp)
+ {
+ my_safe_printf_stderr("%s",
+ "frame pointer is NULL, did you compile with\n"
+ "-fomit-frame-pointer? Aborting backtrace!\n");
+ return;
+ }
+
+ if (!stack_bottom || (uchar*) stack_bottom > (uchar*) &fp)
+ {
+ ulong tmp= MY_MIN(0x10000,thread_stack);
+ /* Assume that the stack starts at the previous even 65K */
+ stack_bottom= (uchar*) (((ulong) &fp + tmp) & ~(ulong) 0xFFFF);
+ my_safe_printf_stderr("Cannot determine thread, fp=%p, "
+ "backtrace may not be correct.\n", fp);
+ }
+ if (fp > (uchar**) stack_bottom ||
+ fp < (uchar**) stack_bottom - thread_stack)
+ {
+ my_safe_printf_stderr("Bogus stack limit or frame pointer, "
+ "fp=%p, stack_bottom=%p, thread_stack=%ld, "
+ "aborting backtrace.\n",
+ fp, stack_bottom, thread_stack);
+ return;
+ }
+
+ my_safe_printf_stderr("%s",
+ "Stack range sanity check OK, backtrace follows:\n");
+#if defined(__alpha__) && defined(__GNUC__)
+ my_safe_printf_stderr("%s",
+ "Warning: Alpha stacks are difficult -"
+ "will be taking some wild guesses, stack trace may be incorrect or "
+ "terminate abruptly\n");
+
+ /* On Alpha, we need to get pc */
+ __asm __volatile__ ("bsr %0, do_next; do_next: "
+ :"=r"(pc)
+ :"r"(pc));
+#endif /* __alpha__ */
+
+ /* We are 1 frame above signal frame with NPTL */
+ sigreturn_frame_count = 1;
+
+ while (fp < (uchar**) stack_bottom)
+ {
+#if defined(__i386__) || defined(__x86_64__)
+ uchar** new_fp = (uchar**)*fp;
+ my_safe_printf_stderr("%p\n",
+ frame_count == sigreturn_frame_count ?
+ *(fp + SIGRETURN_FRAME_OFFSET) : *(fp + 1));
+#endif /* defined(__386__) || defined(__x86_64__) */
+
+#if defined(__alpha__) && defined(__GNUC__)
+ uchar** new_fp = find_prev_fp(pc, fp);
+ if (frame_count == sigreturn_frame_count - 1)
+ {
+ new_fp += 90;
+ }
+
+ if (fp && pc)
+ {
+ pc = find_prev_pc(pc, fp);
+ if (pc)
+ my_safe_printf_stderr("%p\n", pc);
+ else
+ {
+ my_safe_printf_stderr("%s",
+ "Not smart enough to deal with the rest of this stack\n");
+ goto end;
+ }
+ }
+ else
+ {
+ my_safe_printf_stderr("%s",
+ "Not smart enough to deal with the rest of this stack\n");
+ goto end;
+ }
+#endif /* defined(__alpha__) && defined(__GNUC__) */
+ if (new_fp <= fp )
+ {
+ my_safe_printf_stderr("New value of fp=%p failed sanity check, "
+ "terminating stack trace!\n", new_fp);
+ goto end;
+ }
+ fp = new_fp;
+ ++frame_count;
+ }
+ my_safe_printf_stderr("%s",
+ "Stack trace seems successful - bottom reached\n");
+
+end:
+ if (!silent)
+ my_safe_printf_stderr("%s",
+ "Please read "
+ "http://dev.mysql.com/doc/refman/5.1/en/resolve-stack-dump.html\n"
+ "and follow instructions on how to resolve the stack trace.\n"
+ "Resolved stack trace is much more helpful in diagnosing the\n"
+ "problem, so please do resolve it\n");
+}
+#endif /* TARGET_OS_LINUX */
+#endif /* HAVE_STACKTRACE */
+
+/* Produce a core for the thread */
+void my_write_core(int sig)
+{
+#ifdef HAVE_gcov
+ extern void __gcov_flush(void);
+#endif
+ signal(sig, SIG_DFL);
+#ifdef HAVE_gcov
+ /*
+ For GCOV build, crashing will prevent the writing of code coverage
+ information from this process, causing gcov output to be incomplete.
+ So we force the writing of coverage information here before terminating.
+ */
+ __gcov_flush();
+#endif
+ pthread_kill(pthread_self(), sig);
+#if defined(P_MYID) && !defined(SCO)
+ /* On Solaris, the above kill is not enough */
+ sigsend(P_PID,P_MYID,sig);
+#endif
+}
+
+#else /* __WIN__*/
+
+#ifdef _MSC_VER
+/* Silence warning in OS header dbghelp.h */
+#pragma warning(push)
+#pragma warning(disable : 4091)
+#endif
+
+#include <dbghelp.h>
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+#include <tlhelp32.h>
+#include <my_sys.h>
+#if _MSC_VER
+#pragma comment(lib, "dbghelp")
+#endif
+
+static EXCEPTION_POINTERS *exception_ptrs;
+
+#define MODULE64_SIZE_WINXP 576
+#define STACKWALK_MAX_FRAMES 64
+
+void my_set_exception_pointers(EXCEPTION_POINTERS *ep)
+{
+ exception_ptrs = ep;
+}
+
+/*
+ Appends directory to symbol path.
+*/
+static void add_to_symbol_path(char *path, size_t path_buffer_size,
+ char *dir, size_t dir_buffer_size)
+{
+ strcat_s(dir, dir_buffer_size, ";");
+ if (!strstr(path, dir))
+ {
+ strcat_s(path, path_buffer_size, dir);
+ }
+}
+
+/*
+ Get symbol path - semicolon-separated list of directories to search
+ for debug symbols. We expect PDB in the same directory as
+ corresponding exe or dll, so the path is build from directories of
+ the loaded modules. If environment variable _NT_SYMBOL_PATH is set,
+ it's value appended to the symbol search path
+*/
+static void get_symbol_path(char *path, size_t size)
+{
+ HANDLE hSnap;
+ char *envvar;
+ char *p;
+#ifndef DBUG_OFF
+ static char pdb_debug_dir[MAX_PATH + 7];
+#endif
+
+ path[0]= '\0';
+
+#ifndef DBUG_OFF
+ /*
+ Add "debug" subdirectory of the application directory, sometimes PDB will
+ placed here by installation.
+ */
+ GetModuleFileName(NULL, pdb_debug_dir, MAX_PATH);
+ p= strrchr(pdb_debug_dir, '\\');
+ if(p)
+ {
+ *p= 0;
+ strcat_s(pdb_debug_dir, sizeof(pdb_debug_dir), "\\debug;");
+ add_to_symbol_path(path, size, pdb_debug_dir, sizeof(pdb_debug_dir));
+ }
+#endif
+
+ /*
+ Enumerate all modules, and add their directories to the path.
+ Avoid duplicate entries.
+ */
+ hSnap= CreateToolhelp32Snapshot(TH32CS_SNAPMODULE, GetCurrentProcessId());
+ if (hSnap != INVALID_HANDLE_VALUE)
+ {
+ BOOL ret;
+ MODULEENTRY32 mod;
+ mod.dwSize= sizeof(MODULEENTRY32);
+ for (ret= Module32First(hSnap, &mod); ret; ret= Module32Next(hSnap, &mod))
+ {
+ char *module_dir= mod.szExePath;
+ p= strrchr(module_dir,'\\');
+ if (!p)
+ {
+ /*
+ Path separator was not found. Not known to happen, if ever happens,
+ will indicate current directory.
+ */
+ module_dir[0]= '.';
+ module_dir[1]= '\0';
+ }
+ else
+ {
+ *p= '\0';
+ }
+ add_to_symbol_path(path, size, module_dir,sizeof(mod.szExePath));
+ }
+ CloseHandle(hSnap);
+ }
+
+
+ /* Add _NT_SYMBOL_PATH, if present. */
+ envvar= getenv("_NT_SYMBOL_PATH");
+ if(envvar)
+ {
+ strcat_s(path, size, envvar);
+ }
+}
+
+#define MAX_SYMBOL_PATH 32768
+
+/* Platform SDK in VS2003 does not have definition for SYMOPT_NO_PROMPTS*/
+#ifndef SYMOPT_NO_PROMPTS
+#define SYMOPT_NO_PROMPTS 0
+#endif
+
+void my_print_stacktrace(uchar* unused1, ulong unused2, my_bool silent)
+{
+ HANDLE hProcess= GetCurrentProcess();
+ HANDLE hThread= GetCurrentThread();
+ static IMAGEHLP_MODULE64 module= {sizeof(module)};
+ static IMAGEHLP_SYMBOL64_PACKAGE package;
+ DWORD64 addr;
+ DWORD machine;
+ int i;
+ CONTEXT context;
+ STACKFRAME64 frame={0};
+ static char symbol_path[MAX_SYMBOL_PATH];
+
+ if(!exception_ptrs)
+ return;
+
+ /* Copy context, as stackwalking on original will unwind the stack */
+ context = *(exception_ptrs->ContextRecord);
+ /*Initialize symbols.*/
+ SymSetOptions(SYMOPT_LOAD_LINES|SYMOPT_NO_PROMPTS|SYMOPT_DEFERRED_LOADS|SYMOPT_DEBUG);
+ get_symbol_path(symbol_path, sizeof(symbol_path));
+ SymInitialize(hProcess, symbol_path, TRUE);
+
+ /*Prepare stackframe for the first StackWalk64 call*/
+ frame.AddrFrame.Mode= frame.AddrPC.Mode= frame.AddrStack.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
+ /*There is currently no need to support IA64*/
+#pragma error ("unsupported architecture")
+#endif
+
+ package.sym.SizeOfStruct= sizeof(package.sym);
+ package.sym.MaxNameLength= sizeof(package.name);
+
+ /*Walk the stack, output useful information*/
+ for(i= 0; i< STACKWALK_MAX_FRAMES;i++)
+ {
+ DWORD64 function_offset= 0;
+ DWORD line_offset= 0;
+ IMAGEHLP_LINE64 line= {sizeof(line)};
+ BOOL have_module= FALSE;
+ BOOL have_symbol= FALSE;
+ BOOL have_source= FALSE;
+
+ if(!StackWalk64(machine, hProcess, hThread, &frame, &context, 0, 0, 0 ,0))
+ break;
+ addr= frame.AddrPC.Offset;
+
+ have_module= SymGetModuleInfo64(hProcess,addr,&module);
+#ifdef _M_IX86
+ if(!have_module)
+ {
+ /*
+ ModuleInfo structure has been "compatibly" extended in
+ releases after XP, and its size was increased. To make XP
+ dbghelp.dll function happy, pretend passing the old structure.
+ */
+ module.SizeOfStruct= MODULE64_SIZE_WINXP;
+ have_module= SymGetModuleInfo64(hProcess, addr, &module);
+ }
+#endif
+
+ have_symbol= SymGetSymFromAddr64(hProcess, addr, &function_offset,
+ &(package.sym));
+ have_source= SymGetLineFromAddr64(hProcess, addr, &line_offset, &line);
+
+ if(have_module)
+ {
+ const char *base_image_name= my_basename(module.ImageName);
+ my_safe_printf_stderr("%s!", base_image_name);
+ }
+ if(have_symbol)
+ my_safe_printf_stderr("%s()", package.sym.Name);
+
+ else if(have_module)
+ my_safe_printf_stderr("%s", "???");
+
+ if(have_source)
+ {
+ const char *base_file_name= my_basename(line.FileName);
+ my_safe_printf_stderr("[%s:%lu]",
+ base_file_name, line.LineNumber);
+ }
+ my_safe_printf_stderr("%s", "\n");
+ }
+}
+
+
+/*
+ Write dump. The dump is created in current directory,
+ file name is constructed from executable name plus
+ ".dmp" extension
+*/
+void my_write_core(int unused)
+{
+ char path[MAX_PATH];
+ char dump_fname[MAX_PATH]= "core.dmp";
+ MINIDUMP_EXCEPTION_INFORMATION info;
+ HANDLE hFile;
+
+ if(!exception_ptrs)
+ return;
+
+ info.ExceptionPointers= exception_ptrs;
+ info.ClientPointers= FALSE;
+ info.ThreadId= GetCurrentThreadId();
+
+ if(GetModuleFileName(NULL, path, sizeof(path)))
+ {
+ _splitpath(path, NULL, NULL,dump_fname,NULL);
+ strcat_s(dump_fname, sizeof(dump_fname), ".dmp");
+ }
+
+ hFile= CreateFile(dump_fname, GENERIC_WRITE, 0, 0, CREATE_ALWAYS,
+ FILE_ATTRIBUTE_NORMAL, 0);
+ if(hFile)
+ {
+ /* Create minidump */
+ if(MiniDumpWriteDump(GetCurrentProcess(), GetCurrentProcessId(),
+ hFile, MiniDumpNormal, &info, 0, 0))
+ {
+ my_safe_printf_stderr("Minidump written to %s\n",
+ _fullpath(path, dump_fname, sizeof(path)) ?
+ path : dump_fname);
+ }
+ else
+ {
+ my_safe_printf_stderr("MiniDumpWriteDump() failed, last error %u\n",
+ (uint) GetLastError());
+ }
+ CloseHandle(hFile);
+ }
+ else
+ {
+ my_safe_printf_stderr("CreateFile(%s) failed, last error %u\n",
+ dump_fname, (uint) GetLastError());
+ }
+}
+
+
+int my_safe_print_str(const char *val, size_t len)
+{
+ __try
+ {
+ my_write_stderr(val, len);
+ }
+ __except(EXCEPTION_EXECUTE_HANDLER)
+ {
+ my_safe_printf_stderr("%s", "is an invalid string pointer");
+ }
+ return 0;
+}
+#endif /*__WIN__*/
+
+
+size_t my_write_stderr(const void *buf, size_t count)
+{
+ return (size_t) write(fileno(stderr), buf, (uint)count);
+}
+
+
+size_t my_safe_printf_stderr(const char* fmt, ...)
+{
+ char to[512];
+ size_t result;
+ va_list args;
+ va_start(args,fmt);
+ result= my_vsnprintf(to, sizeof(to), fmt, args);
+ va_end(args);
+ my_write_stderr(to, result);
+ return result;
+}