bzr push into mysql-6.0-falcon-team branch (vvaintroub:2831 to 2832)

[Vladislav Vaintroub]

 2832 Vladislav Vaintroub	2008-09-26
      (cherry-pick from 6.0-bugteam repo)
      Bug 35987 - crash report on windows doesn't resolve stack traces.
      The problem here is that symbols can not be loaded, because symbol
      path is not set and  default path does not include the directory
      where PDB is located.
            
      The problem is _not_ reproducible on the same machine where
      mysqld.exe is built - if PDB is not found in the symbol path,
      dbghelp would fallback to fully qualified PDB path as given in the
      executable header and on the build host this will succeed.
            
      The solution is to calculate symbol path and pass it to SymInitialize()
      call.
modified:
  mysys/stacktrace.c

 2831 Sergey Vojtovich	2008-09-25 [merge]
      Merge.
modified:
  mysql-test/r/information_schema.result
  mysql-test/suite/funcs_1/datadict/tables2.inc
  mysql-test/suite/funcs_1/r/is_columns_is.result
  mysql-test/suite/funcs_1/r/is_tables.result
  mysql-test/suite/funcs_1/r/is_tables_innodb.result
  mysql-test/suite/funcs_1/r/is_tables_is.result
  mysql-test/suite/funcs_1/r/is_tables_is_falcon.result
  mysql-test/suite/funcs_1/r/is_tables_memory.result
  mysql-test/suite/funcs_1/r/is_tables_myisam.result
  mysql-test/suite/funcs_1/r/is_tables_mysql.result
  mysql-test/suite/funcs_1/r/is_tables_ndb.result
  sql/sql_show.cc

=== modified file 'mysys/stacktrace.c'
--- a/mysys/stacktrace.c	2008-09-05 00:35:12 +0000
+++ b/mysys/stacktrace.c	2008-09-26 11:24:20 +0000
@@ -314,6 +314,7 @@ void my_write_core(int sig)
 #else /* __WIN__*/
 
 #include <dbghelp.h>
+#include <tlhelp32.h>
 
 /*
   Stack tracing on Windows is implemented using Debug Helper library(dbghelp.dll)
@@ -406,6 +407,68 @@ void my_set_exception_pointers(EXCEPTION
   exception_ptrs = ep;
 }
 
+
+/*
+  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;
+
+  path[0]= '\0';
+  /*
+    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;
+      char *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]= '.';
+        p= module_dir + 1;
+      }
+      *p++= ';';
+      *p= '\0';
+
+      if (!strstr(path, module_dir))
+      {
+        size_t dir_len = strlen(module_dir);
+        if (size > dir_len)
+        {
+          strncat(path, module_dir, size-1);
+          size -= dir_len;
+        }
+      }
+    }
+    CloseHandle(hSnap);
+  }
+
+  /* Add _NT_SYMBOL_PATH, if present. */
+  envvar= getenv("_NT_SYMBOL_PATH");
+  if(envvar && size)
+  {
+    strncat(path, envvar, size-1);
+  }
+}
+
+#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
@@ -422,6 +485,7 @@ void my_print_stacktrace(uchar* unused1,
   int     i;
   CONTEXT context;
   STACKFRAME64 frame={0};
+  static char symbol_path[MAX_SYMBOL_PATH];
 
   if(!exception_ptrs || !init_dbghelp_functions())
     return;
@@ -430,7 +494,8 @@ void my_print_stacktrace(uchar* unused1,
   context = *(exception_ptrs->ContextRecord);
   /*Initialize symbols.*/
   pSymSetOptions(SYMOPT_LOAD_LINES|SYMOPT_NO_PROMPTS|SYMOPT_DEFERRED_LOADS|SYMOPT_DEBUG);
-  pSymInitialize(hProcess,NULL,TRUE);
+  get_symbol_path(symbol_path, sizeof(symbol_path));
+  pSymInitialize(hProcess, symbol_path, TRUE);
 
   /*Prepare stackframe for the first StackWalk64 call*/
   frame.AddrFrame.Mode= frame.AddrPC.Mode= frame.AddrStack.Mode= AddrModeFlat;