Initial support for event engines

1 files changed, 101 insertions, 0 deletions

diff --git a/pcilib/plugin.c b/pcilib/plugin.c
new file mode 100644
index 0000000..663bb27
--- /dev/null
+++ b/pcilib/plugin.c
@@ -0,0 +1,101 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <dlfcn.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "model.h"
+#include "pci.h"
+#include "config.h"
+
+void *pcilib_plugin_load(const char *name) {
+    void *plug;
+    char *fullname;
+    const char *path;
+
+    path = getenv("PCILIB_PLUGIN_DIR");
+    if (!path) path = PCILIB_PLUGIN_DIR;
+
+    fullname = malloc(strlen(path) + strlen(name) + 2);
+    if (!fullname) return NULL;
+
+    sprintf(fullname, "%s/%s", path, name);
+
+    plug = dlopen(fullname, RTLD_LAZY|RTLD_LOCAL);
+    free(fullname);
+
+    return plug;
+}
+
+void pcilib_plugin_close(void *plug) {
+    if (plug) 
+	dlclose(plug);
+
+}
+
+void *pcilib_plugin_get_symbol(void *plug, const char *symbol) {
+    if ((!plug)||(!symbol)) return NULL;
+    return dlsym(plug, symbol);
+}
+
+const pcilib_model_description_t *pcilib_get_plugin_model(pcilib_t *pcilib, void *plug, unsigned short vendor_id, unsigned short device_id, const char *model) {
+    void *get_model;
+
+    if (!plug) return NULL;
+
+    get_model = dlsym(plug, "pcilib_get_event_model");
+    if (!get_model) return NULL;
+
+    return ((const pcilib_model_description_t *(*)(pcilib_t *pcilib, unsigned short vendor_id, unsigned short device_id, const char *model))get_model)(pcilib, vendor_id, device_id, model);
+}
+
+const pcilib_model_description_t *pcilib_find_plugin_model(pcilib_t *pcilib, unsigned short vendor_id, unsigned short device_id, const char *model) {
+    DIR *dir;
+    const char *path;
+    struct dirent *entry;
+
+    void *plugin;
+    const pcilib_model_description_t *model_info = NULL;
+
+
+    path = getenv("PCILIB_PLUGIN_DIR");
+    if (!path) path = PCILIB_PLUGIN_DIR;
+
+    if (model) {
+	plugin = pcilib_plugin_load(model);
+	if (plugin) {
+	    model_info = pcilib_get_plugin_model(pcilib, plugin, vendor_id, device_id, model);
+	    if (model_info) {
+		pcilib->event_plugin = plugin;
+		return model_info;
+	    }
+	    pcilib_plugin_close(plugin);
+	}
+    }
+
+    dir = opendir(path);
+    if (!dir) return NULL;
+
+    while ((entry = readdir(dir))) {
+	const char *suffix = strstr(entry->d_name, ".so");
+	if ((!suffix)||(strlen(suffix) != 3)) continue;
+
+	if ((model)&&(!strcmp(entry->d_name, model))) 
+	    continue;
+
+	plugin = pcilib_plugin_load(entry->d_name);
+	if (plugin) {
+	    model_info = pcilib_get_plugin_model(pcilib, plugin, vendor_id, device_id, model);
+	    if (model_info) {
+		pcilib->event_plugin = plugin;
+		break;
+	    }
+	    pcilib_plugin_close(plugin);
+	}
+    }
+
+    closedir(dir);
+    return model_info;
+}