From 502decd6209511a7c7e897bf86cc458aeca6de7f Mon Sep 17 00:00:00 2001
From: cjihrig <cjihrig@gmail.com>
Date: Sun, 25 Feb 2018 17:42:19 -0500
Subject: [PATCH] win: update uv_os_homedir() to use uv_os_getenv()

This commit refactors uv_os_homedir() to to use uv_os_getenv()
to retrieve the USERPROFILE environment variable. This removes
a fair amount of duplicated code, while introducing the following
changes:

1. The function no longer returns UV_EIO when USERPROFILE is
   longer than MAX_PATH. This can be reinstated by adding a
   check for r == 0 && *size >= MAX_PATH.
2. The USERPROFILE string is now a char*, meaning that it must
   be converted from utf8 to utf16 by uv_os_getenv().

Refs: https://github.com/libuv/libuv/pull/1760
PR-URL: https://github.com/libuv/libuv/pull/1761
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>
---
 src/win/util.c | 50 +++++++-------------------------------------------
 1 file changed, 7 insertions(+), 43 deletions(-)

diff --git a/src/win/util.c b/src/win/util.c
index 3100bc23..3c1d9bed 100644
--- a/src/win/util.c
+++ b/src/win/util.c
@@ -1148,53 +1148,17 @@ int uv_getrusage(uv_rusage_t *uv_rusage) {
 
 int uv_os_homedir(char* buffer, size_t* size) {
   uv_passwd_t pwd;
-  wchar_t path[MAX_PATH];
-  DWORD bufsize;
   size_t len;
   int r;
 
-  if (buffer == NULL || size == NULL || *size == 0)
-    return UV_EINVAL;
+  /* Check if the USERPROFILE environment variable is set first. The task of
+     performing input validation on buffer and size is taken care of by
+     uv_os_getenv(). */
+  r = uv_os_getenv("USERPROFILE", buffer, size);
 
-  /* Check if the USERPROFILE environment variable is set first */
-  len = GetEnvironmentVariableW(L"USERPROFILE", path, MAX_PATH);
-
-  if (len == 0) {
-    r = GetLastError();
-
-    /* Don't return an error if USERPROFILE was not found */
-    if (r != ERROR_ENVVAR_NOT_FOUND)
-      return uv_translate_sys_error(r);
-  } else if (len > MAX_PATH) {
-    /* This should not be possible */
-    return UV_EIO;
-  } else {
-    /* Check how much space we need */
-    bufsize = WideCharToMultiByte(CP_UTF8, 0, path, -1, NULL, 0, NULL, NULL);
-
-    if (bufsize == 0) {
-      return uv_translate_sys_error(GetLastError());
-    } else if (bufsize > *size) {
-      *size = bufsize;
-      return UV_ENOBUFS;
-    }
-
-    /* Convert to UTF-8 */
-    bufsize = WideCharToMultiByte(CP_UTF8,
-                                  0,
-                                  path,
-                                  -1,
-                                  buffer,
-                                  *size,
-                                  NULL,
-                                  NULL);
-
-    if (bufsize == 0)
-      return uv_translate_sys_error(GetLastError());
-
-    *size = bufsize - 1;
-    return 0;
-  }
+  /* Don't return an error if USERPROFILE was not found. */
+  if (r != UV_ENOENT)
+    return r;
 
   /* USERPROFILE is not set, so call uv__getpwuid_r() */
   r = uv__getpwuid_r(&pwd);