Imported Upstream version 93u+upstream

1 files changed, 183 insertions, 0 deletions

diff --git a/src/lib/libdll/dll_lib.c b/src/lib/libdll/dll_lib.c
new file mode 100644
index 0000000..29e4cd8
--- /dev/null
+++ b/src/lib/libdll/dll_lib.c
@@ -0,0 +1,183 @@
+/***********************************************************************
+*                                                                      *
+*               This software is part of the ast package               *
+*          Copyright (c) 1997-2011 AT&T Intellectual Property          *
+*                      and is licensed under the                       *
+*                 Eclipse Public License, Version 1.0                  *
+*                    by AT&T Intellectual Property                     *
+*                                                                      *
+*                A copy of the License is available at                 *
+*          http://www.eclipse.org/org/documents/epl-v10.html           *
+*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
+*                                                                      *
+*              Information and Software Systems Research               *
+*                            AT&T Research                             *
+*                           Florham Park NJ                            *
+*                                                                      *
+*                 Glenn Fowler <gsf@research.att.com>                  *
+*                                                                      *
+***********************************************************************/
+#pragma prototyped
+/*
+ * Glenn Fowler
+ * AT&T Research
+ */
+
+#include "dlllib.h"
+
+typedef void* (*Dll_lib_f)(const char*, void*, const char*);
+
+typedef struct Dll_lib_s
+{
+	struct Dll_lib_s*	next;
+	Dll_lib_f		libf;
+	char*			path;
+	char			base[1];
+} Dll_lib_t;
+
+/*
+ * split <name,base,type,opts> from name into names
+ */
+
+Dllnames_t*
+dllnames(const char* id, const char* name, Dllnames_t* names)
+{
+	char*	s;
+	char*	t;
+	char*	b;
+	char*	e;
+	size_t	n;
+
+	n = strlen(id);
+	if (strneq(name, id, n) && (streq(name + n, "_s") || streq(name + n, "_t")))
+		return 0;
+	if (!names)
+	{
+		s = fmtbuf(sizeof(Dllnames_t*) + sizeof(names) - 1);
+		if (n = (s - (char*)0) % sizeof(names))
+			s += sizeof(names) - n;
+		names = (Dllnames_t*)s;
+	}
+
+	/*
+	 * determine the base name
+	 */
+
+	if ((s = strrchr(name, '/')) || (s = strrchr(name, '\\')))
+		s++;
+	else
+		s = (char*)name;
+	if (strneq(s, "lib", 3))
+		s += 3;
+	b = names->base = names->data;
+	e = b + sizeof(names->data) - 1;
+	t = s;
+	while (b < e && *t && *t != '.' && *t != '-' && *t != ':')
+		*b++ = *t++;
+	*b++ = 0;
+
+	/*
+	 * determine the optional type
+	 */
+
+	if (t = strrchr(s, ':'))
+	{
+		names->name = b;
+		while (b < e && s < t)
+			*b++ = *s++;
+		*b++ = 0;
+		names->type = b;
+		while (b < e && *++t)
+			*b++ = *t;
+		*b++ = 0;
+	}
+	else
+	{
+		names->name = (char*)name;
+		names->type = 0;
+	}
+	*(names->path = b) = 0;
+	names->opts = 0;
+	names->id = (char*)id;
+	return names;
+}
+
+/*
+ * return method pointer for <id,version> in names
+ */
+
+void*
+dll_lib(Dllnames_t* names, unsigned long version, Dllerror_f errorf, void* disc)
+{
+	void*			dll;
+	Dll_lib_t*		lib;
+	Dll_lib_f		libf;
+	int			n;
+	char			sym[64];
+
+	static Dll_lib_t*	loaded;
+
+	if (!names)
+		return 0;
+
+	/*
+	 * check if plugin already loaded
+	 */
+
+	for (lib = loaded; lib; lib = lib->next)
+		if (streq(names->base, lib->base))
+		{
+			libf = lib->libf;
+			goto init;
+		}
+
+	/*
+	 * load
+	 */
+
+	if (!(dll = dllplugin(names->id, names->name, NiL, version, NiL, RTLD_LAZY, names->path, names->data + sizeof(names->data) - names->path)) && (streq(names->name, names->base) || !(dll = dllplugin(names->id, names->base, NiL, version, NiL, RTLD_LAZY, names->path, names->data + sizeof(names->data) - names->path))))
+	{
+		if (errorf)
+			(*errorf)(NiL, disc, 2, "%s: library not found", names->name);
+		return 0;
+	}
+
+	/*
+	 * init
+	 */
+
+	sfsprintf(sym, sizeof(sym), "%s_lib", names->id);
+	if (!(libf = (Dll_lib_f)dlllook(dll, sym)))
+	{
+		if (errorf)
+			(*errorf)(NiL, disc, 2, "%s: %s: initialization function not found in library", names->path, sym);
+		return 0;
+	}
+
+	/*
+	 * add to the loaded list
+	 */
+
+	if (lib = newof(0, Dll_lib_t, 1, (n = strlen(names->base)) + strlen(names->path) + 1))
+	{
+		lib->libf = libf;
+		strcpy(lib->base, names->base);
+		strcpy(lib->path = lib->base + n + 1, names->path);
+		lib->next = loaded;
+		loaded = lib;
+	}
+ init:
+	return (*libf)(names->path, disc, names->type);
+}
+
+/*
+ * return method pointer for <id,name,version>
+ */
+
+void*
+dllmeth(const char* id, const char* name, unsigned long version)
+{
+	Dllnames_t	names;
+
+	return dll_lib(dllnames(id, name, &names), version, 0, 0);
+}