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, 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                    LPCWSTR pszCmdLine)
  44 {
  45         if (pszCmdLine && *pszCmdLine != '\0')
  46                 wcstombs(event_source, pszCmdLine, sizeof(event_source));
  47
  48         /*
  49          * This is an ugly hack due to the strange behavior of "regsvr32 /i".
  50          *
  51          * When installing, regsvr32 calls DllRegisterServer before DllInstall.
  52          * When uninstalling (i.e. "regsvr32 /u /i"), on the other hand, regsvr32
  53          * calls DllInstall and then DllUnregisterServer as expected.
  54          *
  55          * This strange behavior forces us to specify -n (i.e. "regsvr32 /n /i").
  56          * Without -n, DllRegisterServer called before DllInstall would mistakenly
  57          * overwrite the default "PostgreSQL" event source registration.
  58          */
  59         if (bInstall)
  60                 DllRegisterServer();
  61         return S_OK;
  62 }
  63
  64 /*
  65  * DllRegisterServer --- Instructs DLL to create its registry entries
  66  */
  67
  68 STDAPI
  69 DllRegisterServer(void)
  70 {
  71         HKEY            key;
  72         DWORD           data;
  73         char            buffer[_MAX_PATH];
  74         char            key_name[400];
  75
  76         /* Set the name of DLL full path name. */
  77         if (!GetModuleFileName((HMODULE) g_module, buffer, sizeof(buffer)))
  78         {
  79                 MessageBox(NULL, "Could not retrieve DLL filename", "PostgreSQL error", MB_OK | MB_ICONSTOP);
  80                 return SELFREG_E_TYPELIB;
  81         }
  82
  83         /*
  84          * Add PostgreSQL source name as a subkey under the Application key in the
  85          * EventLog registry key.
  86          */
  87         _snprintf(key_name, sizeof(key_name),
  88                         "SYSTEM\\CurrentControlSet\\Services\\EventLog\\Application\\%s",
  89                           event_source);
  90         if (RegCreateKey(HKEY_LOCAL_MACHINE, key_name, &key))
  91         {
  92                 MessageBox(NULL, "Could not create the registry key.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
  93                 return SELFREG_E_TYPELIB;
  94         }
  95
  96         /* Add the name to the EventMessageFile subkey. */
  97         if (RegSetValueEx(key,
  98                                           "EventMessageFile",
  99                                           0,
 100                                           REG_EXPAND_SZ,
 101                                           (LPBYTE) buffer,
 102                                           strlen(buffer) + 1))
 103         {
 104                 MessageBox(NULL, "Could not set the event message file.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 105                 return SELFREG_E_TYPELIB;
 106         }
 107
 108         /* Set the supported event types in the TypesSupported subkey. */
 109         data = EVENTLOG_ERROR_TYPE | EVENTLOG_WARNING_TYPE | EVENTLOG_INFORMATION_TYPE;
 110
 111         if (RegSetValueEx(key,
 112                                           "TypesSupported",
 113                                           0,
 114                                           REG_DWORD,
 115                                           (LPBYTE) &data,
 116                                           sizeof(DWORD)))
 117         {
 118                 MessageBox(NULL, "Could not set the supported types.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 119                 return SELFREG_E_TYPELIB;
 120         }
 121
 122         RegCloseKey(key);
 123         return S_OK;
 124 }
 125
 126 /*
 127  * DllUnregisterServer --- Instructs DLL to remove only those entries created through DllRegisterServer
 128  */
 129
 130 STDAPI
 131 DllUnregisterServer(void)
 132 {
 133         char            key_name[400];
 134
 135         /*
 136          * Remove PostgreSQL source name as a subkey under the Application key in
 137          * the EventLog registry key.
 138          */
 139
 140         _snprintf(key_name, sizeof(key_name),
 141                         "SYSTEM\\CurrentControlSet\\Services\\EventLog\\Application\\%s",
 142                           event_source);
 143         if (RegDeleteKey(HKEY_LOCAL_MACHINE, key_name))
 144         {
 145                 MessageBox(NULL, "Could not delete the registry key.", "PostgreSQL error", MB_OK | MB_ICONSTOP);
 146                 return SELFREG_E_TYPELIB;
 147         }
 148         return S_OK;
 149 }
 150
 151 /*
 152  * DllMain --- is an optional entry point into a DLL.
 153  */
 154
 155 BOOL            WINAPI
 156 DllMain(HANDLE hModule,
 157                 DWORD ul_reason_for_call,
 158                 LPVOID lpReserved
 159 )
 160 {
 161         if (ul_reason_for_call == DLL_PROCESS_ATTACH)
 162                 g_module = hModule;
 163         return TRUE;
 164 }