/* * 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. */ #define _ERRNO_H #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 _stdio_init(void); extern void weak_function _stdio_term(void); extern int *weak_const_function __errno_location (void); extern int *weak_const_function __h_errno_location (void); #else extern void _stdio_init(void); extern void _stdio_term(void); extern int *__errno_location (void); extern int *__h_errno_location (void); #endif /* * 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; /* * Now for our main routine. */ void __uClibc_main(int argc, char **argv, char **envp) { /* * Initialize the global variable __environ. */ __environ = envp; #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 (_stdio_init) _stdio_init(); /* * 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. */ if (__errno_location) *(__errno_location()) = 0; /* Set h_errno to 0 as well */ if (__h_errno_location) *(__h_errno_location()) = 0; /* * Finally, invoke application's main and then exit. */ exit(main(argc, argv, envp)); } #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_term * 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, _stdio_init); weak_alias(__uClibc_empty_func, _stdio_term); #endif #endif