Added support for early and late calls to Vstr wrappers.

That is, prevent a SIGSEGV if Vstr wrappers are called before printf_hook_t
is initialized and after it is destroyed.

diff --git a/src/libstrongswan/printf_hook.c b/src/libstrongswan/printf_hook.c
index 9c1757b9c9148d849edc6a33b9fc343b39f5a008..4d4cef829f223c2a4a845769980bdb9e5759be97 100644 (file)
--- a/src/libstrongswan/printf_hook.c
+++ b/src/libstrongswan/printf_hook.c
@@ -132,6 +132,14 @@ static int custom_arginfo(const struct printf_info *info, size_t n, int *argtype
 #include <errno.h>
 #include <unistd.h> /* for STDOUT_FILENO */
 
+/**
+ * These are used below, whenever the public wrapper functions are called before
+ * initialization or after destruction.
+ */
+#undef vprintf
+#undef vfprintf
+#undef vsnprintf
+
 /**
  * Vstr custom format specifier callback function.
  */
@@ -177,13 +185,16 @@ static void vstr_fmt_add_handler(Vstr_conf *conf, printf_hook_handler_t *handler
        switch(handler->numargs)
        {
                case 1:
-                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0], VSTR_TYPE_FMT_END);
+                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+                                                VSTR_TYPE_FMT_END);
                        break;
                case 2:
-                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0], at[1], VSTR_TYPE_FMT_END);
+                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+                                                at[1], VSTR_TYPE_FMT_END);
                        break;
                case 3:
-                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0], at[1], at[2], VSTR_TYPE_FMT_END);
+                       vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+                                                at[1], at[2], VSTR_TYPE_FMT_END);
                        break;
        }
 }
@@ -193,7 +204,7 @@ static void vstr_fmt_add_handler(Vstr_conf *conf, printf_hook_handler_t *handler
  */
 #include <threading/thread_value.h>
 
-static thread_value_t *vstr_conf;
+static thread_value_t *vstr_conf = NULL;
 
 static Vstr_conf *create_vstr_conf()
 {
@@ -216,12 +227,15 @@ static Vstr_conf *create_vstr_conf()
 
 static inline Vstr_conf *get_vstr_conf()
 {
-       Vstr_conf *conf;
-       conf = (Vstr_conf*)vstr_conf->get(vstr_conf);
-       if (!conf)
+       Vstr_conf *conf = NULL;
+       if (vstr_conf)
        {
-               conf = create_vstr_conf();
-               vstr_conf->set(vstr_conf, conf);
+               conf = (Vstr_conf*)vstr_conf->get(vstr_conf);
+               if (!conf)
+               {
+                       conf = create_vstr_conf();
+                       vstr_conf->set(vstr_conf, conf);
+               }
        }
        return conf;
 }
@@ -274,11 +288,11 @@ int vstr_wrapper_asprintf(char **str, const char *format, ...)
        va_end(args);
        return written;
 }
-static inline int vstr_wrapper_vprintf_internal(int fd, const char *format,
+static inline int vstr_wrapper_vprintf_internal(Vstr_conf *conf, int fd,
+                                                                                               const char *format,
                                                                                                va_list args)
 {
        int written;
-       Vstr_conf *conf = get_vstr_conf();
        Vstr_base *s = vstr_make_base(conf);
        vstr_add_vfmt(s, 0, format, args);
        written = s->len;
@@ -298,24 +312,39 @@ static inline int vstr_wrapper_vprintf_internal(int fd, const char *format,
 }
 int vstr_wrapper_vprintf(const char *format, va_list args)
 {
-       return vstr_wrapper_vprintf_internal(STDOUT_FILENO, format, args);
+       Vstr_conf *conf = get_vstr_conf();
+       if (conf)
+       {
+               return vstr_wrapper_vprintf_internal(conf, STDOUT_FILENO, format, args);
+       }
+       return vprintf(format, args);
 }
 int vstr_wrapper_vfprintf(FILE *stream, const char *format, va_list args)
 {
-       return vstr_wrapper_vprintf_internal(fileno(stream), format, args);
+       Vstr_conf *conf = get_vstr_conf();
+       if (conf)
+       {
+               return vstr_wrapper_vprintf_internal(conf, fileno(stream), format,
+                                                                                        args);
+       }
+       return vfprintf(stream, format, args);
 }
 static inline int vstr_wrapper_vsnprintf_internal(char *str, size_t size,
                                                                                                  const char *format,
                                                                                                  va_list args)
 {
-       int written;
        Vstr_conf *conf = get_vstr_conf();
-       Vstr_base *s = vstr_make_base(conf);
-       vstr_add_vfmt(s, 0, format, args);
-       written = s->len;
-       vstr_export_cstr_buf(s, 1, s->len, str, (size > 0) ? size : s->len + 1);
-       vstr_free_base(s);
-       return written;
+       if (conf)
+       {
+               int written;
+               Vstr_base *s = vstr_make_base(conf);
+               vstr_add_vfmt(s, 0, format, args);
+               written = s->len;
+               vstr_export_cstr_buf(s, 1, s->len, str, (size > 0) ? size : s->len + 1);
+               vstr_free_base(s);
+               return written;
+       }
+       return vsnprintf(str, size, format, args);
 }
 int vstr_wrapper_vsprintf(char *str, const char *format, va_list args)
 {
@@ -346,7 +375,6 @@ int vstr_wrapper_vasprintf(char **str, const char *format, va_list args)
        }
        return written;
 }
-
 #endif
 
 /**
@@ -437,6 +465,7 @@ static void destroy(private_printf_hook_t *this)
 #ifdef USE_VSTR
        /* freeing the Vstr_conf of the main thread */
        vstr_conf->destroy(vstr_conf);
+       vstr_conf = NULL;
        vstr_free_conf(conf);
        vstr_exit();
 #endif