win32: code shrink Unix-style path handling

Replace auto_add_system_drive() with alloc_system_drive() which
leaves space for a possible filename extension.  This makes it
possible to drop alloc_win32_extension() and auto_win32_extension().

Saves 144 bytes.

1 files changed, 14 insertions, 13 deletions

diff --git a/shell/ash.c b/shell/ash.c
index abefba074..7967872f7 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -8784,15 +8784,19 @@ static void shellexec(char *prog, char **argv, const char *path, int idx)
                          */
                         goto try_PATH;
                 }
+                e = errno;
 #if ENABLE_PLATFORM_MINGW32 && ENABLE_FEATURE_SH_STANDALONE
-                if (strcmp(oldprog, prog) != 0 && unix_path(oldprog)) {
-                        if ((applet_no = find_applet_by_name(bb_basename(oldprog))) >= 0)
-                                tryexec(applet_no, bb_basename(oldprog), argv, envp);
-                        else
-                                errno = ENOENT;
+                if (unix_path(oldprog)) {
+                        const char *name = bb_basename(oldprog);
+                        if ((applet_no = find_applet_by_name(name)) >= 0) {
+                                tryexec(applet_no, name, argv, envp);
+                                e = errno;
+                        }
+                        else {
+                                e = ENOENT;
+                        }
                 }
 #endif
-                e = errno;
         } else {
  try_PATH:
                 e = ENOENT;
@@ -14318,16 +14322,13 @@ find_command(char *name, struct cmdentry *entry, int act, const char *path)
 #else /* ENABLE_PLATFORM_MINGW32 */
         /* If name contains a slash or drive prefix, don't use PATH or hash table */
         if (has_path(name)) {
-# if ENABLE_FEATURE_SH_STANDALONE
-                char *oldname = name;
-# endif
-                name = stack_add_system_drive(name);
+                fullname = stack_add_system_drive(name);
                 entry->u.index = -1;
                 if (act & DO_ABS) {
-                        if (!add_win32_extension(name) && stat(name, &statb) < 0) {
+                        if (!add_win32_extension(fullname) && stat(fullname, &statb) < 0) {
 # if ENABLE_FEATURE_SH_STANDALONE
-                                if (unix_path(oldname) &&
-                                                find_applet_by_name(bb_basename(oldname)) >= 0) {
+                                if (unix_path(name) &&
+                                                find_applet_by_name(bb_basename(name)) >= 0) {
                                         entry->cmdtype = CMDNORMAL;
                                         entry->u.index = INT_MIN;
                                         return;