[PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Stephanos Ioannidis]

`HOME` is not a default valid environment variable on Windows.

`USERPROFILE` environment variable should be used to resolve the user
home directory path.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
---
 gdb/auto-load.c            |  4 ++++
 gdb/gdbsupport/pathstuff.c |  4 ++++
 gdb/main.c                 |  4 ++++
 gdb/windows-nat.c          |  4 ++++
 gnulib/import/glob.c       | 22 ++--------------------
 5 files changed, 18 insertions(+), 20 deletions(-)

diff --git a/gdb/auto-load.c b/gdb/auto-load.c
index 5a9f47f078..7f88967b82 100644
--- a/gdb/auto-load.c
+++ b/gdb/auto-load.c
@@ -499,6 +499,10 @@ file_is_auto_load_safe (const char *filename, const char *debug_fmt, ...)
   if (!advice_printed)
     {
       const char *homedir = getenv ("HOME");
+#ifdef _WIN32
+      if (homedir == NULL)
+	homedir = getenv ("USERPROFILE");
+#endif
 
       if (homedir == NULL)
 	homedir = "$HOME";
diff --git a/gdb/gdbsupport/pathstuff.c b/gdb/gdbsupport/pathstuff.c
index f9882a2635..a90587103c 100644
--- a/gdb/gdbsupport/pathstuff.c
+++ b/gdb/gdbsupport/pathstuff.c
@@ -231,6 +231,10 @@ get_standard_cache_dir ()
 #endif
 
   const char *home = getenv ("HOME");
+#ifdef _WIN32
+  if (home == NULL)
+    home = getenv ("USERPROFILE");
+#endif
   if (home != NULL)
     {
       /* Make sure the path is absolute and tilde-expanded.  */
diff --git a/gdb/main.c b/gdb/main.c
index 66a9e6a6d2..2a7228f20c 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -300,6 +300,10 @@ get_init_files (std::vector<std::string> *system_gdbinit,
 	}
 
       const char *homedir = getenv ("HOME");
+#ifdef _WIN32
+      if (homedir == NULL)
+        homedir = getenv ("USERPROFILE");
+#endif
 
       /* If the .gdbinit file in the current directory is the same as
 	 the $HOME/.gdbinit file, it should not be sourced.  homebuf
diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index 31a5cabfb3..e60298ff60 100644
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -3201,6 +3201,10 @@ _initialize_check_for_gdb_ini (void)
     return;
 
   homedir = getenv ("HOME");
+#ifdef _WIN32
+  if (homedir == NULL)
+    homedir = getenv ("USERPROFILE");
+#endif
   if (homedir)
     {
       char *p;
diff --git a/gnulib/import/glob.c b/gnulib/import/glob.c
index 416d210b63..eea1189e05 100644
--- a/gnulib/import/glob.c
+++ b/gnulib/import/glob.c
@@ -663,27 +663,9 @@ glob (const char *pattern, int flags, int (*errfunc) (const char *, int),
           if (home_dir == NULL || home_dir[0] == '\0')
             home_dir = "SYS:";
 # else
-#  ifdef WINDOWS32
-          /* Windows NT defines HOMEDRIVE and HOMEPATH.  But give preference
-             to HOME, because the user can change HOME.  */
+#  ifdef _WIN32
           if (home_dir == NULL || home_dir[0] == '\0')
-            {
-              const char *home_drive = getenv ("HOMEDRIVE");
-              const char *home_path = getenv ("HOMEPATH");
-
-              if (home_drive != NULL && home_path != NULL)
-                {
-                  size_t home_drive_len = strlen (home_drive);
-                  size_t home_path_len = strlen (home_path);
-                  char *mem = alloca (home_drive_len + home_path_len + 1);
-
-                  memcpy (mem, home_drive, home_drive_len);
-                  memcpy (mem + home_drive_len, home_path, home_path_len + 1);
-                  home_dir = mem;
-                }
-              else
-                home_dir = "c:/users/default"; /* poor default */
-            }
+            home_dir = getenv ("USERPROFILE");
 #  else
           if (home_dir == NULL || home_dir[0] == '\0')
             {
-- 
2.26.2

Re: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Eli Zaretskii]

> From: Stephanos Ioannidis <root@stephanos.io>
> Date: Tue,  2 Jun 2020 12:49:42 +0900
> Cc: Stephanos Ioannidis <root@stephanos.io>
> 
> `HOME` is not a default valid environment variable on Windows.
> 
> `USERPROFILE` environment variable should be used to resolve the user
> home directory path.

AFAIU, putting files in USERPROFILE is against MS platform
recommendations.  See

  https://docs.microsoft.com/en-us/windows/win32/shell/csidl

Under CSIDL_PROFILE, it says:

  Applications should not create files or folders at this level; they
  should put their data under the locations referred to by
  CSIDL_APPDATA or CSIDL_LOCAL_APPDATA.

Thanks.

RE: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Stephanos Ioannidis]

Thanks for the feedback.

> AFAIU, putting files in USERPROFILE is against MS platform recommendations.

From what I can see, I do not think that is necessarily the case.

%USERPROFILE% points to the user-specific home directory on Windows (i.e. $HOME equivalent), which is one of the following:

 * Windows XP or earlier:   C:\Documents and Settings\username
 * Windows Vista and later: C:\Users\username

Many modern Windows programs, including the ones from Microsoft, make use of %USERPROFILE% as the place to store various user-specific data; for example, the following is what I have under %USERPROFILE% on my Windows machine:

====
C:\Users\assem>dir .*
 Volume in drive C is Windows
 Volume Serial Number is 6A91-6C3C

 Directory of C:\Users\assem

05/24/2020  09:29 PM    <DIR>          .
05/24/2020  09:29 PM    <DIR>          ..
12/25/2019  11:51 AM    <DIR>          .android
06/23/2019  02:36 AM    <DIR>          .AndroidStudio3.4
05/30/2020  03:05 PM             2,570 .bash_history
09/29/2019  12:21 AM    <DIR>          .cache
01/01/2020  12:17 PM    <DIR>          .dotnet
09/20/2019  02:05 PM    <DIR>          .eclipse
09/16/2019  08:44 PM    <DIR>          .ghidra
05/23/2020  04:26 PM               145 .gitconfig
11/19/2019  09:45 AM    <DIR>          .gradle
11/19/2019  09:45 AM    <DIR>          .idea
08/27/2019  07:58 PM    <DIR>          .jssc
11/24/2019  12:07 AM    <DIR>          .mcc
11/23/2019  11:57 PM    <DIR>          .mchp_packs
06/22/2019  03:13 PM    <DIR>          .mplabcomm
06/17/2019  08:09 PM    <DIR>          .nuget
06/17/2019  05:06 PM    <DIR>          .oracle_jre_usage
09/20/2019  02:05 PM    <DIR>          .p2
10/06/2019  02:55 PM    <DIR>          .ssh
12/09/2019  12:47 AM    <DIR>          .templateengine
05/24/2020  09:29 PM            17,012 .viminfo
06/17/2019  02:47 PM    <DIR>          .vscode
               3 File(s)         19,727 bytes
              20 Dir(s)  523,199,340,544 bytes free
====

In fact, I can see that gnulib itself already uses %HOMEDRIVE%%HOMEPATH (identical to %USERPROFILE%) in place of $HOME for Windows.

-----Original Message-----
From: Eli Zaretskii <eliz@gnu.org> 
Sent: Wednesday, June 3, 2020 12:15 AM
To: Stephanos Ioannidis <root@stephanos.io>
Cc: gdb-patches@sourceware.org
Subject: Re: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

> From: Stephanos Ioannidis <root@stephanos.io>
> Date: Tue,  2 Jun 2020 12:49:42 +0900
> Cc: Stephanos Ioannidis <root@stephanos.io>
> 
> `HOME` is not a default valid environment variable on Windows.
> 
> `USERPROFILE` environment variable should be used to resolve the user 
> home directory path.

AFAIU, putting files in USERPROFILE is against MS platform recommendations.  See

  https://docs.microsoft.com/en-us/windows/win32/shell/csidl

Under CSIDL_PROFILE, it says:

  Applications should not create files or folders at this level; they
  should put their data under the locations referred to by
  CSIDL_APPDATA or CSIDL_LOCAL_APPDATA.

Thanks.

Re: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Eli Zaretskii]

> From: Stephanos Ioannidis <root@stephanos.io>
> CC: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
> Date: Tue, 2 Jun 2020 15:49:03 +0000
> 
> > AFAIU, putting files in USERPROFILE is against MS platform recommendations.
> 
> >From what I can see, I do not think that is necessarily the case.
> 
> %USERPROFILE% points to the user-specific home directory on Windows (i.e. $HOME equivalent), which is one of the following:
> 
>  * Windows XP or earlier:   C:\Documents and Settings\username
>  * Windows Vista and later: C:\Users\username
> 
> Many modern Windows programs, including the ones from Microsoft, make use of %USERPROFILE% as the place to store various user-specific data; for example, the following is what I have under %USERPROFILE% on my Windows machine:

The fact that many programs violate these recommendations doesn't yet
mean those recommendations are null and void, nor that GDB should join
the club.  Emacs, for example, didn't join that club.

Anyway, that's my opinion; if others don't mind putting our files
directly under USERPROFILE, they can override me.

Re: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Christian Biesinger]

On Mon, Jun 1, 2020 at 10:50 PM Stephanos Ioannidis <root@stephanos.io> wrote:
> --- a/gdb/auto-load.c
> +++ b/gdb/auto-load.c
> @@ -499,6 +499,10 @@ file_is_auto_load_safe (const char *filename, const char *debug_fmt, ...)
>    if (!advice_printed)
>      {
>        const char *homedir = getenv ("HOME");
> +#ifdef _WIN32
> +      if (homedir == NULL)
> +       homedir = getenv ("USERPROFILE");
> +#endif

You're adding this in a lot of places; probably better to add a helper
function in gdbsupport to return the home/userprofile directory?

> diff --git a/gnulib/import/glob.c b/gnulib/import/glob.c
> index 416d210b63..eea1189e05 100644
> --- a/gnulib/import/glob.c
> +++ b/gnulib/import/glob.c

Gnulib is maintained elsewhere, please send patches to
bug-gnulib@gnu.org. If the change is also needed in GDB, it is best to
wait for Gnulib to add the patch and then use gnulib/update-gnulib.sh.
Though it's also possible to add a local patch.

Christian

Re: [PATCH] Use USERPROFILE environment variable to resolve home path on Windows

[Tom Tromey]

>>>>> "Christian" == Christian Biesinger via Gdb-patches <gdb-patches@sourceware.org> writes:

Christian> On Mon, Jun 1, 2020 at 10:50 PM Stephanos Ioannidis <root@stephanos.io> wrote:
>> --- a/gdb/auto-load.c
>> +++ b/gdb/auto-load.c
>> @@ -499,6 +499,10 @@ file_is_auto_load_safe (const char *filename, const char *debug_fmt, ...)
>> if (!advice_printed)
>> {
>> const char *homedir = getenv ("HOME");
>> +#ifdef _WIN32
>> +      if (homedir == NULL)
>> +       homedir = getenv ("USERPROFILE");
>> +#endif

Christian> You're adding this in a lot of places; probably better to add a helper
Christian> function in gdbsupport to return the home/userprofile directory?

Agreed; there's also a use of $HOME in gdbsupport, so presumably this
would have to be fixed as well anyway.

Tom