freetdm: print stack trace in sample ftdmload app

diff --git a/libs/freetdm/sample/dso/ftdmload.c b/libs/freetdm/sample/dso/ftdmload.c
index 9d313b382d903ea0c47cb341cf79dee528dc9665..5b150d67ed8a8646e576adf7652304d7f0d85bb8 100644 (file)
--- a/libs/freetdm/sample/dso/ftdmload.c
+++ b/libs/freetdm/sample/dso/ftdmload.c
@@ -1,7 +1,10 @@
+#define _GNU_SOURCE
 #include <stdio.h>
 #include <stdlib.h>
 #include <freetdm.h>
 #include <ftdm_dso.h>
+#include <dlfcn.h>
+#include <execinfo.h>
 
 #define ARRLEN(obj) (sizeof(obj)/sizeof(obj[0]))
 
@@ -12,6 +15,65 @@ struct dso_entry {
 
 struct dso_entry loaded[10];
 
+static void *(*real_dlopen)(const char *filename, int flag) = NULL;
+static int (*real_dlclose)(void *handle) = NULL;
+
+static void print_stack()
+{
+       void *stacktrace[100];
+       char **symbols;
+       int size;
+       int i;
+       size = backtrace(stacktrace, ARRLEN(stacktrace));
+       symbols = backtrace_symbols(stacktrace, size);
+       if (!symbols) {
+               return;
+       }
+       for (i = 0; i < size; i++) {
+               ftdm_log(FTDM_LOG_DEBUG, "%s\n", symbols[i]);
+       }
+       free(symbols);
+}
+
+void *dlopen(const char *filename, int flag)
+{
+       char *msg = NULL;
+       void *handle = NULL;
+       print_stack();
+       if (real_dlopen == NULL) {
+               dlerror();
+               real_dlopen = dlsym(RTLD_NEXT, "dlopen");
+               if ((msg = dlerror()) != NULL) {
+                       fprintf(stderr, "dlsym failed: %s\n", msg);
+                       exit(1);
+               }
+               fprintf(stderr, "Real dlopen at addr %p\n", real_dlopen);
+       }
+       handle = real_dlopen(filename, flag);
+       if (!handle) {
+               return NULL;
+       }
+       ftdm_log(FTDM_LOG_NOTICE, "Loaded %s with handle %p\n", filename, handle);
+       return handle;
+}
+
+int dlclose(void *handle)
+{
+       char *msg = NULL;
+       print_stack();
+       if (real_dlclose == NULL) {
+               dlerror();
+               real_dlclose = dlsym(RTLD_NEXT, "dlclose");
+               if ((msg = dlerror()) != NULL) {
+                       fprintf(stderr, "dlsym failed: %s\n", msg);
+                       exit(1);
+               }
+               fprintf(stderr, "Real dlclose at addr %p\n", real_dlclose);
+       }
+       ftdm_log(FTDM_LOG_NOTICE, "Unloading %p\n", handle);
+       return real_dlclose(handle);
+}
+
 int load(char *name)
 {
        char path[255];