Re: [PATCH] libtool on cygwin [1/4]: cygwin doesn't use LoadLibrary

[Gary V. Vaughan]

Charles Wilson wrote:
> Gary V. Vaughan wrote:
>
> > Charles Wilson wrote:
> >
> > > -#ifdef __WINDOWS__
> > > +#if defined(__WINDOWS__) || defined(__CYGWIN__)
> >
> >
> >
> > > -#  ifdef __WINDOWS__
> > > +#  if defined(__WINDOWS__) && !defined(__CYGWIN__)
> >
> >
> >
> > Huh?  Is __WINDOWS__ (or WIN32 or _WIN32) defined on cygwin, or not?  
> > If it is, the first change is unneccessary, otherwise the second 
> > change is bogus.
>
>
> It depends.  Most recent cygwin compilers (< 2yrs old?) do not define 
> WIN32 or related symbols.  But older ones did.
>
> So, for recent compilers, the first change is necessary but the second 
> one is not; for older compilers the second change is required by the 
> first one is not.
>
> Welcome to my world.

Shudder! :-)  Okay, I'm applying this patch, which relies on my earlier 
28-gary-canonicalise-__WINDOWS__.patch for the sake of your sanity.

Can you check that I didn't break anything please?  The intention is to leave 
the LoadLibrary loader on cygwin, but only use it if the dlopen loader fails 
for some reason (or the programmer wishes to force LoadLibrary), so you should 
still see dlopen being used.

Cheers,
        Gary.
--
  ())_.  Gary V. Vaughan    gary@(lilith.warpmail.net|gnu.org)
  ( '/   Research Scientist http://www.oranda.demon.co.uk       ,_())____
  / )=   GNU Hacker         http://www.gnu.org/software/libtool  \'      `&
`(_~)_   Tech' Author       http://sources.redhat.com/autobook   =`---d__/

Index: ChangeLog
from  Charles Wilson  <address@hidden>,
        Gary V. Vaughan  <address@hidden>

        * libltdl/ltdl.c (LT_USE_POSIX_DIRENT): Factored out.
        (LT_USE_WINDOWS_DIRENT_EMULATION): Move to after include "ltdl.h",
        as they are affected by __WINDOWS__ definition.
        (LT_READTEXT_MODE): Use textmode to read .la files.
        (lt_dlinit): Use LoadLibrary loader as a fallback on cygwin.

Index: libltdl/ltdl.c
===================================================================
RCS file: /cvsroot/libtool/libtool/libltdl/ltdl.c,v
retrieving revision 1.181
diff -u -p -u -r1.181 ltdl.c
--- libltdl/ltdl.c      7 Oct 2003 22:29:05 -0000       1.181
+++ libltdl/ltdl.c      6 Nov 2003 13:42:34 -0000
@@ -67,55 +67,6 @@ Foundation, Inc., 59 Temple Place, Suite
 #  include <errno.h>
 #endif
 
-
-#ifndef __WINDOWS__
-#  ifdef __WIN32__
-#    define __WINDOWS__
-#  endif
-#endif
-
-
-#undef LT_USE_POSIX_DIRENT
-#ifdef HAVE_CLOSEDIR
-#  ifdef HAVE_OPENDIR
-#    ifdef HAVE_READDIR
-#      ifdef HAVE_DIRENT_H
-#        define LT_USE_POSIX_DIRENT
-#      endif /* HAVE_DIRENT_H */
-#    endif /* HAVE_READDIR */
-#  endif /* HAVE_OPENDIR */
-#endif /* HAVE_CLOSEDIR */
-
-
-#undef LT_USE_WINDOWS_DIRENT_EMULATION
-#ifndef LT_USE_POSIX_DIRENT
-#  ifdef __WINDOWS__
-#    define LT_USE_WINDOWS_DIRENT_EMULATION
-#  endif /* __WINDOWS__ */
-#endif /* LT_USE_POSIX_DIRENT */
-
-
-#ifdef LT_USE_POSIX_DIRENT
-#  include <dirent.h>
-#  define LT_D_NAMLEN(dirent) (strlen((dirent)->d_name))
-#else
-#  ifdef LT_USE_WINDOWS_DIRENT_EMULATION
-#    define LT_D_NAMLEN(dirent) (strlen((dirent)->d_name))
-#  else
-#    define dirent direct
-#    define LT_D_NAMLEN(dirent) ((dirent)->d_namlen)
-#    if HAVE_SYS_NDIR_H
-#      include <sys/ndir.h>
-#    endif
-#    if HAVE_SYS_DIR_H
-#      include <sys/dir.h>
-#    endif
-#    if HAVE_NDIR_H
-#      include <ndir.h>
-#    endif
-#  endif
-#endif
-
 #if HAVE_ARGZ_H
 #  include <argz.h>
 #endif
@@ -128,6 +79,31 @@ Foundation, Inc., 59 Temple Place, Suite
 
 #include "ltdl.h"
 
+#if defined(HAVE_CLOSEDIR) && defined(HAVE_OPENDIR) && defined(HAVE_READDIR) 
&& defined(HAVE_DIRENT_H)
+/* We have a fully operational dirent subsystem.  */
+# include <dirent.h>
+# define LT_D_NAMLEN(dirent) (strlen((dirent)->d_name))
+
+#elif !defined(__WINDOWS__)
+/* We are not on windows, so we can get the same functionality from the
+   `direct' API.  */
+# define dirent direct
+# define LT_D_NAMLEN(dirent) ((dirent)->d_namlen)
+# if HAVE_SYS_NDIR_H
+#   include <sys/ndir.h>
+# endif
+# if HAVE_SYS_DIR_H
+#   include <sys/dir.h>
+# endif
+# if HAVE_NDIR_H
+#   include <ndir.h>
+# endif
+
+#else  /* __WINDOWS__ */
+/* Use some wrapper code to emulate dirent on windows..  */
+# define LT_USE_WINDOWS_DIRENT_EMULATION
+#endif
+
 #if WITH_DMALLOC
 #  include <dmalloc.h>
 #endif
@@ -146,34 +122,12 @@ Foundation, Inc., 59 Temple Place, Suite
 
 /* fopen() mode flags for reading a text file */
 #undef LT_READTEXT_MODE
-#ifdef __WINDOWS__
+#if defined(__WINDOWS__) || defined(__CYGWIN__)
 #  define LT_READTEXT_MODE "rt"
 #else
 #  define LT_READTEXT_MODE "r"
 #endif
 
-#ifdef LT_USE_WINDOWS_DIRENT_EMULATION
-
-#include <windows.h>
-
-#define dirent lt_dirent
-#define DIR lt_DIR
-
-struct dirent
-{
-  char d_name[2048];
-  int  d_namlen;
-};
-
-typedef struct _DIR
-{
-  HANDLE hSearch;
-  WIN32_FIND_DATA Win32FindData;
-  BOOL firsttime;
-  struct dirent file_info;
-} DIR;
-
-#endif /* LT_USE_WINDOWS_DIRENT_EMULATION */
 
 
 /* --- MANIFEST CONSTANTS --- */
@@ -427,17 +381,37 @@ memmove (dest, src, size)
 
 #endif /* !HAVE_MEMMOVE */
 
-#ifdef LT_USE_WINDOWS_DIRENT_EMULATION
+# if LT_USE_WINDOWS_DIRENT_EMULATION
+
+# include <windows.h>
+
+# define LT_D_NAMLEN(dirent) (strlen((dirent)->d_name))
+# define dirent lt_dirent
+# define DIR lt_DIR
+
+struct dirent
+{
+  char d_name[2048];
+  int  d_namlen;
+};
+
+typedef struct _DIR
+{
+  HANDLE hSearch;
+  WIN32_FIND_DATA Win32FindData;
+  BOOL firsttime;
+  struct dirent file_info;
+} DIR;
 
 static void closedir LT_PARAMS((DIR *entry));
 
 static void
-closedir(entry)
-  DIR *entry;
+closedir (entry)
+    DIR *entry;
 {
-  assert(entry != (DIR *) NULL);
-  FindClose(entry->hSearch);
-  lt_dlfree((lt_ptr)entry);
+  assert (entry != (DIR *) NULL);
+  FindClose (entry->hSearch);
+  lt_dlfree ((lt_ptr) entry);
 }
 
 
@@ -445,58 +419,65 @@ static DIR * opendir LT_PARAMS((const ch
 
 static DIR*
 opendir (path)
-  const char *path;
+    const char *path;
 {
   char file_specification[LT_FILENAME_MAX];
   DIR *entry;
 
-  assert(path != (char *) NULL);
-  (void) strncpy(file_specification,path,LT_FILENAME_MAX-1);
-  (void) strcat(file_specification,"\\");
-  entry = LT_DLMALLOC (DIR,sizeof(DIR));
+  assert (path != (char *) NULL);
+  (void) strncpy (file_specification, path, LT_FILENAME_MAX-1);
+  (void) strcat (file_specification, "\\");
+  entry = LT_DLMALLOC (DIR, sizeof(DIR));
   if (entry != (DIR *) 0)
     {
       entry->firsttime = TRUE;
-      entry->hSearch = FindFirstFile(file_specification,&entry->Win32FindData);
+      entry->hSearch = FindFirstFile (file_specification,
+                                     &entry->Win32FindData);
     }
+
   if (entry->hSearch == INVALID_HANDLE_VALUE)
     {
-      (void) strcat(file_specification,"\\*.*");
-      entry->hSearch = FindFirstFile(file_specification,&entry->Win32FindData);
+      (void) strcat (file_specification, "\\*.*");
+      entry->hSearch = FindFirstFile (file_specification,
+                                     &entry->Win32FindData);
       if (entry->hSearch == INVALID_HANDLE_VALUE)
         {
           LT_DLFREE (entry);
           return (DIR *) 0;
         }
     }
-  return(entry);
+
+  return entry;
 }
 
 
 static struct dirent *readdir LT_PARAMS((DIR *entry));
 
-static struct dirent *readdir(entry)
-  DIR *entry;
+static struct dirent *
+readdir (entry)
+    DIR *entry;
 {
-  int
-    status;
+  int status;
 
   if (entry == (DIR *) 0)
-    return((struct dirent *) 0);
+    return (struct dirent *) 0;
+
   if (!entry->firsttime)
     {
-      status = FindNextFile(entry->hSearch,&entry->Win32FindData);
+      status = FindNextFile (entry->hSearch, &entry->Win32FindData);
       if (status == 0)
-        return((struct dirent *) 0);
+        return (struct dirent *) 0;
     }
+
   entry->firsttime = FALSE;
-  (void) strncpy(entry->file_info.d_name,entry->Win32FindData.cFileName,
-    LT_FILENAME_MAX-1);
-  entry->file_info.d_namlen = strlen(entry->file_info.d_name);
-  return(&entry->file_info);
+  (void) strncpy (entry->file_info.d_name, entry->Win32FindData.cFileName,
+                 LT_FILENAME_MAX - 1);
+  entry->file_info.d_namlen = strlen (entry->file_info.d_name);
+
+  return &entry->file_info;
 }
+#endif /* !LT_USE_WINDOWS_DIRENT_EMULATION */
 
-#endif /* LT_USE_WINDOWS_DIRENT_EMULATION */
 
 /* According to Alexandre Oliva <address@hidden>,
     ``realloc is not entirely portable''
@@ -1290,7 +1271,7 @@ static struct lt_user_dlloader sys_shl =
 
 /* --- LOADLIBRARY() INTERFACE LOADER --- */
 
-#ifdef __WINDOWS__
+#if defined(__WINDOWS__) || defined(__CYGWIN__)
 
 /* dynamic linking for Win32 */
 
@@ -2202,14 +2183,14 @@ lt_dlinit ()
       handles = 0;
       user_search_path = 0; /* empty search path */
 
+#if defined(__WINDOWS__) || defined(__CYGWIN__)
+      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_wll, "dlopen");
+#endif
 #if HAVE_LIBDL
       errors += lt_dlloader_add (lt_dlloader_next (0), &sys_dl, "dlopen");
 #endif
 #if HAVE_SHL_LOAD
       errors += lt_dlloader_add (lt_dlloader_next (0), &sys_shl, "dlopen");
-#endif
-#ifdef __WINDOWS__
-      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_wll, "dlopen");
 #endif
 #ifdef __BEOS__
       errors += lt_dlloader_add (lt_dlloader_next (0), &sys_bedl, "dlopen");