openrc/src/rc-plugin.c
2007-04-19 14:41:10 +00:00

118 lines
2.2 KiB
C

/*
librc-plugin.c
Simple plugin handler
Copyright 2007 Gentoo Foundation
Released under the GPLv2
*/
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "einfo.h"
#include "rc.h"
#include "rc-misc.h"
#include "rc-plugin.h"
#include "strlist.h"
typedef struct plugin
{
char *name;
void *handle;
int (*hook) (rc_hook_t hook, const char *name);
struct plugin *next;
} plugin_t;
static plugin_t *plugins = NULL;
void rc_plugin_load (void)
{
char **files;
char *file;
int i;
plugin_t *plugin = plugins;
/* Ensure some sanity here */
rc_plugin_unload ();
if (! rc_exists (RC_PLUGINDIR))
return;
files = rc_ls_dir (NULL, RC_PLUGINDIR, 0);
STRLIST_FOREACH (files, file, i) {
char *p = rc_strcatpaths (RC_PLUGINDIR, file, NULL);
/*
* We load the use RTLD_NOW so that we know it works
* as if we have any unknown symbols when we run then the
* program bails out in rc_plugin_run which is very very bad.
*/
void *h = dlopen (p, RTLD_NOW);
char *func;
void *f;
int len;
if (! h) {
eerror ("dlopen: %s", dlerror ());
free (p);
continue;
}
func = file;
file = strsep (&func, ".");
len = strlen (file) + 7;
func = rc_xmalloc (sizeof (char *) * len);
snprintf (func, len, "_%s_hook", file);
f = dlsym (h, func);
if (! f) {
eerror ("`%s' does not expose the symbol `%s'", p, func);
dlclose (h);
} else {
if (plugin) {
plugin->next = rc_xmalloc (sizeof (plugin_t));
plugin = plugin->next;
} else
plugin = plugins = rc_xmalloc (sizeof (plugin_t));
memset (plugin, 0, sizeof (plugin_t));
plugin->name = strdup (file);
plugin->handle = h;
plugin->hook = f;
}
free (func);
free (p);
}
rc_strlist_free (files);
}
void rc_plugin_run (rc_hook_t hook, const char *value)
{
plugin_t *plugin = plugins;
while (plugin) {
if (plugin->hook)
plugin->hook (hook, value);
plugin = plugin->next;
}
}
void rc_plugin_unload (void)
{
plugin_t *plugin = plugins;
plugin_t *next;
while (plugin) {
next = plugin->next;
dlclose (plugin->handle);
free (plugin->name);
free (plugin);
plugin = next;
}
plugins = NULL;
}