Use snprintf instead of wsprintf, and use getenv("APPDATA") instead of

SHGetFolderPath.

This removes the direct dependency on shell32.dll and user32.dll, which
eats a lot of "desktop heap" for each backend that's started. The
desktop heap is a very limited resource, causing backends to no
longer start once it's been exhausted.

We still have indirect depdendencies on user32.dll through third party
libraries, but those can't easily be removed.

Dave Page

3 files changed, 11 insertions, 7 deletions

diff --git a/src/backend/port/win32/signal.c b/src/backend/port/win32/signal.c
index 9c48df3114..91bc957919 100644
--- a/src/backend/port/win32/signal.c
+++ b/src/backend/port/win32/signal.c
@@ -178,7 +178,7 @@ pgwin32_create_signal_listener(pid_t pid)
 	char		pipename[128];
 	HANDLE		pipe;
 
-	wsprintf(pipename, "\\\\.\\pipe\\pgsignal_%d", (int) pid);
+	snprintf(pipename, sizeof(pipename), "\\\\.\\pipe\\pgsignal_%u", (int) pid);
 
 	pipe = CreateNamedPipe(pipename, PIPE_ACCESS_DUPLEX,
 					   PIPE_TYPE_MESSAGE | PIPE_READMODE_MESSAGE | PIPE_WAIT,
@@ -251,7 +251,7 @@ pg_signal_thread(LPVOID param)
 	char		pipename[128];
 	HANDLE		pipe = pgwin32_initial_signal_pipe;
 
-	wsprintf(pipename, "\\\\.\\pipe\\pgsignal_%d", GetCurrentProcessId());
+	snprintf(pipename, sizeof(pipename), "\\\\.\\pipe\\pgsignal_%u", GetCurrentProcessId());
 
 	for (;;)
 	{
diff --git a/src/port/kill.c b/src/port/kill.c
index 30f3b8e5fb..907f5e8c6f 100644
--- a/src/port/kill.c
+++ b/src/port/kill.c
@@ -38,7 +38,7 @@ pgkill(int pid, int sig)
 		errno = EINVAL;
 		return -1;
 	}
-	wsprintf(pipename, "\\\\.\\pipe\\pgsignal_%i", pid);
+	snprintf(pipename, sizeof(pipename), "\\\\.\\pipe\\pgsignal_%u", pid);
 	if (!CallNamedPipe(pipename, &sigData, 1, &sigRet, 1, &bytes, 1000))
 	{
 		if (GetLastError() == ERROR_FILE_NOT_FOUND)
diff --git a/src/port/path.c b/src/port/path.c
index ba4be40008..acc3cdc260 100644
--- a/src/port/path.c
+++ b/src/port/path.c
@@ -628,10 +628,14 @@ get_home_path(char *ret_path)
 	strlcpy(ret_path, pwd->pw_dir, MAXPGPATH);
 	return true;
 #else
-	char		tmppath[MAX_PATH];
-
-	ZeroMemory(tmppath, sizeof(tmppath));
-	if (SHGetFolderPath(NULL, CSIDL_APPDATA, NULL, 0, tmppath) != S_OK)
+	char		*tmppath;
+
+    /*
+     * Note: We use getenv here because the more modern SHGetSpecialFolderPath()
+     * will force us to link with shell32.lib which eats valuable desktop heap.
+     */
+    tmppath = getenv("APPDATA");
+	if (!tmppath)
 		return false;
 	snprintf(ret_path, MAXPGPATH, "%s/postgresql", tmppath);
 	return true;