Refine win32env.c cosmetics.

Replace use of plain 0 as a null pointer constant.  In comments, update
terminology and lessen redundancy.  Back-patch to 9.2 (all supported
versions) for the convenience of back-patching the next two commits.

Christian Ullrich and Noah Misch, reviewed (in earlier versions) by
Michael Paquier.
This commit is contained in:
Noah Misch 2016-12-03 15:46:35 -05:00
parent 19fcc0058e
commit a9d9208c15
1 changed files with 21 additions and 29 deletions

View File

@ -1,9 +1,8 @@
/*-------------------------------------------------------------------------
*
* win32env.c
* putenv() and unsetenv() for win32, that updates both process
* environment and the cached versions in (potentially multiple)
* MSVCRT.
* putenv() and unsetenv() for win32, which update both process environment
* and caches in (potentially multiple) C run-time library (CRT) versions.
*
* Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
@ -24,17 +23,10 @@ pgwin32_putenv(const char *envval)
char *cp;
/*
* Each version of MSVCRT has its own _putenv() call in the runtime
* library.
*
* mingw always uses MSVCRT.DLL, but if we are in a Visual C++
* environment, attempt to update the environment in all MSVCRT modules
* that are currently loaded, to work properly with any third party
* libraries linked against a different MSVCRT but still relying on
* environment variables.
*
* Also separately update the system environment that gets inherited by
* subprocesses.
* Each CRT has its own _putenv() symbol and copy of the environment.
* Update the environment in each CRT module currently loaded, so every
* third-party library sees this change regardless of the CRT it links
* against.
*/
#ifdef _MSC_VER
typedef int (_cdecl * PUTENVPROC) (const char *);
@ -46,34 +38,34 @@ pgwin32_putenv(const char *envval)
} rtmodules[] =
{
{
"msvcrt", 0, NULL
}, /* Visual Studio 6.0 / mingw */
"msvcrt", NULL, NULL
}, /* Visual Studio 6.0 / MinGW */
{
"msvcr70", 0, NULL
"msvcr70", NULL, NULL
}, /* Visual Studio 2002 */
{
"msvcr71", 0, NULL
"msvcr71", NULL, NULL
}, /* Visual Studio 2003 */
{
"msvcr80", 0, NULL
"msvcr80", NULL, NULL
}, /* Visual Studio 2005 */
{
"msvcr90", 0, NULL
"msvcr90", NULL, NULL
}, /* Visual Studio 2008 */
{
"msvcr100", 0, NULL
"msvcr100", NULL, NULL
}, /* Visual Studio 2010 */
{
"msvcr110", 0, NULL
"msvcr110", NULL, NULL
}, /* Visual Studio 2012 */
{
"msvcr120", 0, NULL
"msvcr120", NULL, NULL
}, /* Visual Studio 2013 */
{
"ucrtbase", 0, NULL
"ucrtbase", NULL, NULL
}, /* Visual Studio 2015 and later */
{
NULL, 0, NULL
NULL, NULL, NULL
}
};
int i;
@ -82,7 +74,7 @@ pgwin32_putenv(const char *envval)
{
if (rtmodules[i].putenvFunc == NULL)
{
if (rtmodules[i].hmodule == 0)
if (rtmodules[i].hmodule == NULL)
{
/* Not attempted before, so try to find this DLL */
rtmodules[i].hmodule = GetModuleHandle(rtmodules[i].modulename);
@ -121,8 +113,8 @@ pgwin32_putenv(const char *envval)
#endif /* _MSC_VER */
/*
* Update the process environment - to make modifications visible to child
* processes.
* Update process environment, making this change visible to child
* processes and to CRTs initializing in the future.
*
* Need a copy of the string so we can modify it.
*/
@ -142,7 +134,7 @@ pgwin32_putenv(const char *envval)
/*
* Only call SetEnvironmentVariable() when we are adding a variable,
* not when removing it. Calling it on both crashes on at least
* certain versions of MingW.
* certain versions of MinGW.
*/
if (!SetEnvironmentVariable(envcpy, cp))
{