win32: revert special treatment of Unix-style absolute paths

Commit 605972390 (win32: handle Unix-style absolute paths for
executables) added special treatment of paths for executables
starting with a slash.  Such paths are absolute on Unix but are
relative to the current drive on Windows.  On reflection this
commit did more than necessary.  Later commits provided special
treatment only for paths starting with locations traditionally
used to contain binaries on Unix.  This is probably sufficient.

Problems introduced by commit 605972390 include:

- If the current drive isn't the system drive tab completion of a
  command starting with a slash confusingly references the system
  drive.

- Building busybox-w32 with w64devkit fails on drives other than
  the system drive.

Revert the changes introduced by commit 605972390.

This saves 192 bytes.

(GitHub issue #239)

2 files changed, 1 insertions, 4 deletions

diff --git a/libbb/executable.c b/libbb/executable.c
index 32b37f29d..770aedc0c 100644
--- a/libbb/executable.c
+++ b/libbb/executable.c
@@ -57,7 +57,7 @@ char* FAST_FUNC find_executable(const char *filename, char **PATHp)
                 );
 #if ENABLE_PLATFORM_MINGW32
                 {
-                        char *w = alloc_system_drive(p);
+                        char *w = alloc_ext_space(p);
                         ex = add_win32_extension(w) || file_is_executable(w);
                         free(p);
                         p = w;
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index c5d5808f5..b4950688e 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -972,9 +972,6 @@ static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type)
                 }
 
                 lpath = *paths[i] ? paths[i] : ".";
-#if ENABLE_PLATFORM_MINGW32
-                lpath = auto_string(alloc_system_drive(lpath));
-#endif
                 dir = opendir(lpath);
                 if (!dir)
                         continue; /* don't print an error */