libc.h

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// MIT License
//
// Copyright (c) 2026 Christian Spoo
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
 
#ifndef _USER_LIBC_H_
#define _USER_LIBC_H_
 
typedef unsigned long  size_t;
typedef long           ssize_t;
typedef long           pid_t;
 
/* Syscall wrappers implemented in syscall.asm */
ssize_t write(int fd, const void *buf, size_t count);
ssize_t read(int fd, void *buf, size_t count);
int     open(const char *path);   /* O_RDONLY, no flags needed for kernel */
int     close(int fd);
void    exit(int code) __attribute__((noreturn));
pid_t   fork(void);
int     exec(const char *path);   /* simplified: no argv -- shell passes command name only */
 
/* wait() wraps _libc_wait because 'wait' is a reserved mnemonic in NASM */
pid_t   _libc_wait(int *status);
static inline pid_t wait(int *status) { return _libc_wait(status); }
 
/* waitpid(): wait for specific child pid.  Use this instead of wait() to avoid
 * passing a status pointer where the kernel expects a child TID. */
pid_t   waitpid(pid_t pid, int *status, int options);
 
#endif /* _USER_LIBC_H_ */