win32: code shrink detection of executables

Add a function, file_is_win32_exe(), to detect if a path refers
to an executable.  It tries adding extensions if necessary.

Use this in a number of places to replace common code of the form

   path = alloc_ext_space(cmd);
   if (add_win32_extension(path) || file_is_executable(path))

Saves 32-48 bytes.

1 files changed, 2 insertions, 1 deletions

diff --git a/include/mingw.h b/include/mingw.h
index e49483307..7e6109f2e 100644
--- a/include/mingw.h
+++ b/include/mingw.h
@@ -559,7 +559,9 @@ void init_codepage(void);
 int has_bat_suffix(const char *p);
 int has_exe_suffix(const char *p);
 int has_exe_suffix_or_dot(const char *name);
+char *alloc_ext_space(const char *path);
 int add_win32_extension(char *p);
+char *file_is_win32_exe(const char *name);
 
 char *bs_to_slash(char *p) FAST_FUNC;
 void slash_to_bs(char *p) FAST_FUNC;
@@ -578,7 +580,6 @@ int unc_root_len(const char *dir);
 int root_len(const char *path);
 const char *get_system_drive(void);
 const char *need_system_drive(const char *path);
-char *alloc_ext_space(const char *path);
 int chdir_system_drive(void);
 char *xabsolute_path(char *path);
 char *get_drive_cwd(const char *path, char *buffer, int size);