* dlfcn.cc (dlerror): Only report load errors once per error.

2 files changed, 160 insertions, 0 deletions

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index fc3bfcb8150..8a29585ddfa 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,5 +1,9 @@
 2003-01-31  Christopher Faylor  <cgf@redhat.com>
 
+	* dlfcn.cc (dlerror): Only report load errors once per error.
+
+2003-01-31  Christopher Faylor  <cgf@redhat.com>
+
 	* fhandler_serial.cc (fhandler_serial::open): Avoid extraneous setting
 	of res.
 
diff --git a/winsup/cygwin/dlfcn.cc b/winsup/cygwin/dlfcn.cc
new file mode 100644
index 00000000000..b03f685fc6a
--- /dev/null
+++ b/winsup/cygwin/dlfcn.cc
@@ -0,0 +1,156 @@
+/* dlfcn.cc
+
+   Copyright 1998, 2000, 2001 Red Hat, Inc.
+
+This file is part of Cygwin.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+#include "winsup.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <ctype.h>
+#include "security.h"
+#include "fhandler.h"
+#include "perprocess.h"
+#include "path.h"
+#include "thread.h"
+#include "dlfcn.h"
+#include "dll_init.h"
+#include "cygerrno.h"
+
+#define _dl_error _reent_winsup ()->_dl_error
+#define _dl_buffer _reent_winsup ()->_dl_buffer
+
+static void __stdcall
+set_dl_error (const char *str)
+{
+  __small_sprintf (_dl_buffer, "%s: %E", str);
+  _dl_error = 1;
+}
+
+/* Look for an executable file given the name and the environment
+   variable to use for searching (eg., PATH); returns the full
+   pathname (static buffer) if found or NULL if not. */
+inline const char * __stdcall
+check_path_access (const char *mywinenv, const char *name, path_conv& buf)
+{
+  return find_exec (name, buf, mywinenv, FE_NNF | FE_NATIVE | FE_CWD);
+}
+
+/* Search LD_LIBRARY_PATH for dll, if it exists.
+   Return Windows version of given path. */
+static const char * __stdcall
+get_full_path_of_dll (const char* str, char *name)
+{
+  int len = strlen (str);
+
+  /* empty string or too long to be legal win32 pathname? */
+  if (len == 0 || len >= MAX_PATH - 1)
+    return str;		/* Yes.  Let caller deal with it. */
+
+  const char *ret;
+
+  strcpy (name, str);	/* Put it somewhere where we can manipulate it. */
+
+  /* Add extension if necessary */
+  if (str[len - 1] != '.')
+    {
+      /* Add .dll only if no extension provided. */
+      const char *p = strrchr (str, '.');
+      if (!p || strpbrk (p, "\\/"))
+	strcat (name, ".dll");
+    }
+
+  path_conv real_filename;
+
+  if (isabspath (name) ||
+      (ret = check_path_access ("LD_LIBRARY_PATH=", name, real_filename)) == NULL)
+    real_filename.check (name);	/* Convert */
+
+  if (!real_filename.error)
+    ret = strcpy (name, real_filename);
+  else
+    {
+      set_errno (real_filename.error);
+      ret = NULL;
+    }
+
+  return ret;
+}
+
+void *
+dlopen (const char *name, int)
+{
+  SetResourceLock (LOCK_DLL_LIST, READ_LOCK | WRITE_LOCK, "dlopen");
+
+  void *ret;
+
+  if (name == NULL)
+    ret = (void *) GetModuleHandle (NULL); /* handle for the current module */
+  else
+    {
+      char buf[MAX_PATH];
+      /* handle for the named library */
+      const char *fullpath = get_full_path_of_dll (name, buf);
+      if (!fullpath)
+	ret = NULL;
+      else
+	{
+	  ret = (void *) LoadLibrary (fullpath);
+	  if (ret == NULL)
+	    __seterrno ();
+	}
+    }
+
+  if (!ret)
+    set_dl_error ("dlopen");
+  debug_printf ("ret %p", ret);
+
+  ReleaseResourceLock (LOCK_DLL_LIST, READ_LOCK | WRITE_LOCK, "dlopen");
+  return ret;
+}
+
+void *
+dlsym (void *handle, const char *name)
+{
+  void *ret = (void *) GetProcAddress ((HMODULE) handle, name);
+  if (!ret)
+    set_dl_error ("dlsym");
+  debug_printf ("ret %p", ret);
+  return ret;
+}
+
+int
+dlclose (void *handle)
+{
+  SetResourceLock (LOCK_DLL_LIST, READ_LOCK | WRITE_LOCK, "dlclose");
+
+  int ret = -1;
+  void *temphandle = (void *) GetModuleHandle (NULL);
+  if (temphandle == handle || FreeLibrary ((HMODULE) handle))
+    ret = 0;
+  if (ret)
+    set_dl_error ("dlclose");
+  CloseHandle ((HMODULE) temphandle);
+
+  ReleaseResourceLock (LOCK_DLL_LIST, READ_LOCK | WRITE_LOCK, "dlclose");
+  return ret;
+}
+
+char *
+dlerror ()
+{
+  char *res;
+  if (!_dl_error)
+    res = NULL;
+  else
+    {
+      _dl_error = 0;
+      res = _dl_buffer;
+    }
+  return res;
+}