granicus.if.org Git - postgresql/blob - src/bin/pgevent/pgevent.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * pgevent.c
   4  *              Defines the entry point for pgevent dll.
   5  *              The DLL defines event source for backend
   6  *
   7  *
   8  * IDENTIFICATION
   9  *        src/bin/pgevent/pgevent.c
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14
  15 #include <windows.h>
  16 #include <olectl.h>
  17 #include <string.h>
  18 #include <stdio.h>
  19 #include <stdlib.h>
  20
  21 /* Global variables */
  22 HANDLE          g_module = NULL;        /* hModule of DLL */
  23
  24 /*
  25  * The event source is stored as a registry key.
  26  * The maximum length of a registry key is 255 characters.
  27  * http://msdn.microsoft.com/en-us/library/ms724872(v=vs.85).aspx
  28  */
  29 char            event_source[256] = "PostgreSQL";
  30
  31 /* Prototypes */
  32 HRESULT         DllInstall(BOOL bInstall, __in_opt LPCWSTR pszCmdLine);
  33 STDAPI          DllRegisterServer(void);
  34 STDAPI          DllUnregisterServer(void);
  35 BOOL WINAPI DllMain(HANDLE hModule, DWORD ul_reason_for_call, LPVOID lpReserved);
  36
  37 /*
  38  * DllInstall --- Passes the command line argument to DLL
  39  */
  40
  41 HRESULT
  42 DllInstall(BOOL bInstall,
  43                    __in_opt LPCWSTR pszCmdLine)
  44 {
  45         size_t          ret;
  46
  47         if (pszCmdLine && *pszCmdLine != '\0')
  48                 wcstombs_s(&ret, event_source, sizeof(event_source),
  49                                    pszCmdLine, sizeof(event_source));
  50
  51         /*
  52          * This is an ugly hack due to the strange behavior of "regsvr32 /i".
  53          *
  54          * When installing, regsvr32 calls DllRegisterServer before DllInstall.
  55          * When uninstalling (i.e. "regsvr32 /u /i"), on the other hand, regsvr32
  56          * calls DllInstall and then DllUnregisterServer as expected.
  57          *
  58          * This strange behavior forces us to specify -n (i.e. "regsvr32 /n /i").
  59          * Without -n, DllRegisterServer called before DllInstall would mistakenly
  60          * overwrite the default "PostgreSQL" event source registration.
  61          */
  62         if (bInstall)
  63                 DllRegisterServer();
  64         return S_OK;
  65 }
  66
  67 /*
  68  * DllRegisterServer --- Instructs DLL to create its registry entries
  69  */
  70
  71 STDAPI
  72 DllRegisterServer(void)
  73 {
  74         HKEY            key;
  75         DWORD           data;
  76         char            buffer[_MAX_PATH];
  77         char            key_name[400];
  78
  79         /* Set the name of DLL full path name. */
  80         if (!GetModuleFileName((HMODULE) g_module, buffer, sizeof(buffer)))
  81         {
  82                 MessageBox(NULL, "Could not retrieve DLL filename", "PostgreSQL error", MB_OK | MB_ICONSTOP);
  83                 return SELFREG_E_TYPELIB;
  84         }
  85
  86         /*
  87          * Add PostgreSQL source name as a subkey under the Application key in the
  88          * EventLog registry key.
  89          */
  90         _snprintf(key_name, sizeof(key_name),
  91                         "SYSTEM\\CurrentControlSet\\Services\\EventLog\\Application\\%s",
  92                           event_source);
  93         if (RegCreateKey(HKEY_LOCAL_MACHINE, key_name, &key))
  94         {
  95                 MessageBox(NULL, "Could not create the registry key.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
  96                 return SELFREG_E_TYPELIB;
  97         }
  98
  99         /* Add the name to the EventMessageFile subkey. */
 100         if (RegSetValueEx(key,
 101                                           "EventMessageFile",
 102                                           0,
 103                                           REG_EXPAND_SZ,
 104                                           (LPBYTE) buffer,
 105                                           strlen(buffer) + 1))
 106         {
 107                 MessageBox(NULL, "Could not set the event message file.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 108                 return SELFREG_E_TYPELIB;
 109         }
 110
 111         /* Set the supported event types in the TypesSupported subkey. */
 112         data = EVENTLOG_ERROR_TYPE | EVENTLOG_WARNING_TYPE | EVENTLOG_INFORMATION_TYPE;
 113
 114         if (RegSetValueEx(key,
 115                                           "TypesSupported",
 116                                           0,
 117                                           REG_DWORD,
 118                                           (LPBYTE) & data,
 119                                           sizeof(DWORD)))
 120         {
 121                 MessageBox(NULL, "Could not set the supported types.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 122                 return SELFREG_E_TYPELIB;
 123         }
 124
 125         RegCloseKey(key);
 126         return S_OK;
 127 }
 128
 129 /*
 130  * DllUnregisterServer --- Instructs DLL to remove only those entries created through DllRegisterServer
 131  */
 132
 133 STDAPI
 134 DllUnregisterServer(void)
 135 {
 136         char            key_name[400];
 137
 138         /*
 139          * Remove PostgreSQL source name as a subkey under the Application key in
 140          * the EventLog registry key.
 141          */
 142
 143         _snprintf(key_name, sizeof(key_name),
 144                         "SYSTEM\\CurrentControlSet\\Services\\EventLog\\Application\\%s",
 145                           event_source);
 146         if (RegDeleteKey(HKEY_LOCAL_MACHINE, key_name))
 147         {
 148                 MessageBox(NULL, "Could not delete the registry key.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 149                 return SELFREG_E_TYPELIB;
 150         }
 151         return S_OK;
 152 }
 153
 154 /*
 155  * DllMain --- is an optional entry point into a DLL.
 156  */
 157
 158 BOOL            WINAPI
 159 DllMain(HANDLE hModule,
 160                 DWORD ul_reason_for_call,
 161                 LPVOID lpReserved
 162 )
 163 {
 164         if (ul_reason_for_call == DLL_PROCESS_ATTACH)
 165                 g_module = hModule;
 166         return TRUE;
 167 }