/* * Manuel Novoa III Feb 2001 * * __uClibc_main is the routine to be called by all the arch-specific * versions of crt0.S in uClibc. * * It is meant to handle any special initialization needed by the library * such as setting the global variable(s) __environ (environ) and * initializing the stdio package. Using weak symbols, the latter is * avoided in the static library case. */ #include #include #include /* * Prototypes. */ extern int main(int argc, char **argv, char **envp); void __uClibc_main(int argc, char **argv, char **envp) __attribute__ ((__noreturn__)); #ifdef HAVE_ELF weak_alias(__environ, environ); extern void weak_function __init_stdio(void); extern void weak_function __stdio_close_all(void); extern void weak_function __pthread_initialize_minimal (void); #else extern void __init_stdio(void); extern void __stdio_close_all(void); extern void __pthread_initialize_minimal (void); #endif typedef void (*vfuncp) (void); vfuncp __uClibc_cleanup = __stdio_close_all; /* * Now for our main routine. */ void __uClibc_main(int argc, char **argv, char **envp) { /* * Initialize the global variable __environ. */ __environ = envp; /* Initialize the thread library at least a bit so at least * errno will be properly setup */ if (__pthread_initialize_minimal) __pthread_initialize_minimal (); #if 0 /* Some security at this point. Prevent starting a SUID binary * where the standard file descriptors are not opened. We have * to do this only for statically linked applications since * otherwise the dynamic loader did the work already. */ if (__builtin_expect (__libc_enable_secure, 0)) __libc_check_standard_fds (); #endif /* * Initialize stdio here. In the static library case, this will * be bypassed if not needed because of the weak alias above. */ if (__init_stdio) __init_stdio(); /* * Note: It is possible that any initialization done above could * have resulted in errno being set nonzero, so set it to 0 before * we call main. */ __set_errno(0); /* * Finally, invoke application's main and then exit. */ exit(main(argc, argv, envp)); } /* * Declare the __environ global variable and create a weak alias environ. * Note: Apparently we must initialize __environ for the weak environ * symbol to be included. */ char **__environ = 0; #ifndef HAVE_ELF /* * Define an empty function and use it as a weak alias for the stdio * initialization routine. That way we don't pull in all the stdio * code unless we need to. Similarly, do the same for __stdio_close_all * so as not to include atexit unnecessarily. * * NOTE!!! This is only true for the _static_ case!!! */ weak_alias(__environ, environ); #if 0 void __uClibc_empty_func(void) { } weak_alias(__uClibc_empty_func, __init_stdio); weak_alias(__uClibc_empty_func, __stdio_close_all); #endif #endif