6 files changed, 114 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 473682d..c895ba7 100644
--- a/Makefile
+++ b/Makefile
@@ -4,12 +4,12 @@ EXT = -std=gnu99
 CFLAGS = -g -Wall # -O2
 INCLUDES = -I. -I/usr/local/include
 
-LIBS = -L. -lparsevent
+LIBS = -L. -lparsevent -ldl
 
 %.o: %.c
         $(CC) -c $(CFLAGS) $(EXT) $(INCLUDES) $< -o $@
 
-TARGETS = libparsevent.a trace-cmd
+TARGETS = libparsevent.a trace-cmd test_plugin
 
 all: $(TARGETS)
 
@@ -35,6 +35,12 @@ libparsevent.so: $(LIB_OBJS)
 libparsevent.a: $(LIB_OBJS)
         $(RM) $@;  $(AR) rcs $@ $^
 
+test_plugin.o: test_plugin.c parse-events.h
+        $(CC) -c $(CFLAGS) -fPIC -o $@ $<
+
+test_plugin: test_plugin.o
+        $(CC) -shared -nostartfiles -o $@ $<
+
 .PHONY: force
 force:
 
diff --git a/parse-events.h b/parse-events.h
index 2f950dd..ceffef2 100644
--- a/parse-events.h
+++ b/parse-events.h
@@ -45,6 +45,11 @@ extern int trace_seq_do_printf(struct trace_seq *s);
 
 /* ----------------------- pevent ----------------------- */
 
+typedef int (*pevent_plugin_load_func)(void);
+#define PEVENT_PLUGIN_LOADER pevent_plugin_loader
+#define MAKE_STR(x) #x
+#define PEVENT_PLUGIN_LOADER_NAME MAKE_STR(pevent_plugin_loader)
+
 #define NSECS_PER_SEC           1000000000ULL
 #define NSECS_PER_USEC          1000ULL
 
diff --git a/test_plugin.c b/test_plugin.c
new file mode 100644
index 0000000..fd62c27
--- /dev/null
+++ b/test_plugin.c
@@ -0,0 +1,11 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "parse-events.h"
+
+int PEVENT_PLUGIN_LOADER(void)
+{
+        printf("HELLO WORLD!!!\n");
+        return 0;
+}
diff --git a/trace-cmd.h b/trace-cmd.h
index 369e796..1a33d04 100644
--- a/trace-cmd.h
+++ b/trace-cmd.h
@@ -20,6 +20,8 @@ void parse_cmdlines(char *file, int size);
 void parse_proc_kallsyms(char *file, unsigned int size);
 void parse_ftrace_printk(char *file, unsigned int size);
 
+int trace_load_plugins(void);
+
 enum {
         RINGBUF_TYPE_PADDING            = 29,
         RINGBUF_TYPE_TIME_EXTEND        = 30,
diff --git a/trace-read.c b/trace-read.c
index 1c62c4b..3f76833 100644
--- a/trace-read.c
+++ b/trace-read.c
@@ -735,6 +735,8 @@ int read_trace_files(void)
         read_proc_kallsyms();
         read_ftrace_printk();
 
+        trace_load_plugins();
+
         return 0;
 }
 
diff --git a/trace-util.c b/trace-util.c
index 1ff5d5f..b60b680 100644
--- a/trace-util.c
+++ b/trace-util.c
@@ -2,10 +2,17 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <dirent.h>
 #include <ctype.h>
 #include <errno.h>
+#include <dlfcn.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 
 #include "parse-events.h"
+#include "trace-cmd.h"
+
+#define PLUGIN_DIR ".trace-cmd/plugins"
 
 void parse_cmdlines(char *file, int size __unused)
 {
@@ -73,3 +80,82 @@ void parse_ftrace_printk(char *file, unsigned int size __unused)
                 line = strtok_r(NULL, "\n", &next);
         }
 }
+
+static int load_plugin(const char *path, const char *file)
+{
+        char *plugin;
+        void *handle;
+        pevent_plugin_load_func func;
+        int ret;
+
+        plugin = malloc_or_die(strlen(path) + strlen(file) + 2);
+
+        strcpy(plugin, path);
+        strcat(plugin, "/");
+        strcat(plugin, file);
+
+        handle = dlopen(plugin, RTLD_NOW);
+        if (!handle) {
+                warning("cound not load plugin '%s'", plugin);
+                return -1;
+        }
+
+        func = dlsym(handle, PEVENT_PLUGIN_LOADER_NAME);
+        if (!func) {
+                warning("cound not find func '%s' in plugin '%s'",
+                        PEVENT_PLUGIN_LOADER_NAME, plugin);
+                return -1;
+        }
+
+        ret = func();
+
+        /* dlclose ?? */
+        return ret;
+}
+
+int trace_load_plugins(void)
+{
+        struct dirent *dent;
+        struct stat st;
+        DIR *dir;
+        char *home;
+        char *path;
+        int ret;
+
+
+        home = getenv("HOME");
+
+        if (!home)
+                return -1;
+
+        path = malloc_or_die(strlen(home) + strlen(PLUGIN_DIR) + 2);
+
+        strcpy(path, home);
+        strcat(path, "/");
+        strcat(path, PLUGIN_DIR);
+
+        ret = stat(path, &st);
+        if (ret < 0)
+                goto fail;
+
+        if (!S_ISDIR(st.st_mode))
+                goto fail;
+
+        dir = opendir(path);
+        if (!dir)
+                goto fail;
+
+        while ((dent = readdir(dir))) {
+                const char *name = dent->d_name;
+
+                if (strcmp(name, ".") == 0 ||
+                    strcmp(name, "..") == 0)
+                        continue;
+
+                load_plugin(path, name);
+        }
+
+ fail:
+        free(path);
+        return -1;
+}