Don't call pgwin32_message_to_UTF16() without CurrentMemoryContext.

PostgreSQL running as a Windows service crashed upon calling
write_stderr() before MemoryContextInit().  This fix completes work
started in 5735efee15540765315aa8c1a230575e756037f7.  Messages this
early contain only ASCII bytes; if we removed the CurrentMemoryContext
requirement, the ensuing conversions would have no effect.  Back-patch
to 9.3 (all supported versions).

Takayuki Tsunakawa, reviewed by Michael Paquier.

Discussion: https://postgr.es/m/0A3221C70F24FB45833433255569204D1F80CC73@G01JPEXMBYT05

diff --git a/src/backend/utils/error/elog.c b/src/backend/utils/error/elog.c
index eace0ac10005401c4fecc279f74a353eda3f6f70..7e977e8b18b35a388251f0649ba58fc82fb2a615 100644 (file)
--- a/src/backend/utils/error/elog.c
+++ b/src/backend/utils/error/elog.c
@@ -2117,10 +2117,15 @@ write_eventlog(int level, const char *line, int len)
         * try to convert the message to UTF16 and write it with ReportEventW().
         * Fall back on ReportEventA() if conversion failed.
         *
+        * Since we palloc the structure required for conversion, also fall
+        * through to writing unconverted if we have not yet set up
+        * CurrentMemoryContext.
+        *
         * Also verify that we are not on our way into error recursion trouble due
         * to error messages thrown deep inside pgwin32_message_to_UTF16().
         */
        if (!in_error_recursion_trouble() &&
+               CurrentMemoryContext != NULL &&
                GetMessageEncoding() != GetACPEncoding())
        {
                utf16 = pgwin32_message_to_UTF16(line, len, NULL);

diff --git a/src/backend/utils/mb/mbutils.c b/src/backend/utils/mb/mbutils.c
index 7f1c881cceec7a5fc451a49b550375dc7b54b6b4..4dcb833d83636f4fcded154e76775c4b4f30e3bd 100644 (file)
--- a/src/backend/utils/mb/mbutils.c
+++ b/src/backend/utils/mb/mbutils.c
@@ -1049,8 +1049,10 @@ GetMessageEncoding(void)
 
 #ifdef WIN32
 /*
- * Result is palloc'ed null-terminated utf16 string. The character length
- * is also passed to utf16len if not null. Returns NULL iff failed.
+ * Convert from MessageEncoding to a palloc'ed, null-terminated utf16
+ * string. The character length is also passed to utf16len if not
+ * null. Returns NULL iff failed. Before MessageEncoding initialization, "str"
+ * should be ASCII-only; this will function as though MessageEncoding is UTF8.
  */
 WCHAR *
 pgwin32_message_to_UTF16(const char *str, int len, int *utf16len)