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/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
/*
* C Run Time support for NOLIBC
* Copyright (C) 2023 Zhangjin Wu <falcon@tinylab.org>
*/
#ifndef _NOLIBC_CRT_H
#define _NOLIBC_CRT_H
char **environ __attribute__((weak));
const unsigned long *_auxv __attribute__((weak));
static void exit(int);
void _start_c(long *sp)
{
long argc;
char **argv;
char **envp;
const unsigned long *auxv;
/* silence potential warning: conflicting types for 'main' */
int _nolibc_main(int, char **, char **) __asm__ ("main");
/*
* sp : argc <-- argument count, required by main()
* argv: argv[0] <-- argument vector, required by main()
* argv[1]
* ...
* argv[argc-1]
* null
* environ: environ[0] <-- environment variables, required by main() and getenv()
* environ[1]
* ...
* null
* _auxv: _auxv[0] <-- auxiliary vector, required by getauxval()
* _auxv[1]
* ...
* null
*/
/* assign argc and argv */
argc = *sp;
argv = (void *)(sp + 1);
/* find environ */
environ = envp = argv + argc + 1;
/* find _auxv */
for (auxv = (void *)envp; *auxv++;)
;
_auxv = auxv;
/* go to application */
exit(_nolibc_main(argc, argv, envp));
}
#endif /* _NOLIBC_CRT_H */
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