* Hook output functions (like printf(3)) with LD_PRELOAD to color stderr (or
* other file descriptors).
*
- * Copyright (C) 2013-2014 Simon Ruderich
+ * Copyright (C) 2013-2018 Simon Ruderich
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* isn't allowed to perform any memory-modifications before the exec()
* (except the pid_t result variable of vfork()).
*
- * As some programs don't adhere to the standard (e.g. the "child" closes
- * or dups a descriptor before the exec()) and this breaks our tracking of
- * file descriptors (e.g. it gets closed in the parent as well), we just
- * fork() instead. This is in compliance with the POSIX standard and as
- * most systems use copy-on-write anyway not a performance issue. */
+ * As we have to store changes to the file descriptors in memory (e.g. the
+ * "child" closes or dups a descriptor before the exec()) and this
+ * modifies the parent as well due to the semantics of vfork() - thus
+ * breaking the requirements of vfork(), we just use fork instead(). This
+ * is in compliance with the POSIX standard and as most systems use
+ * copy-on-write anyway not a performance issue. */
return fork();
}
#endif
HOOK_FUNC_DEF3(int, execve, char const *, filename, char * const *, argv, char * const *, env) {
DLSYM_FUNCTION(real_execve, "execve");
+ char * const fake_env[] = {NULL};
+ if (env == NULL) {
+ env = fake_env;
+ }
+
/* Count environment variables. */
size_t count = 0;
char * const *x = env;