diff options
Diffstat (limited to 'sys')
| -rw-r--r-- | sys/kern/kern_syscalls.c | 94 | ||||
| -rw-r--r-- | sys/sys/sysent.h | 34 |
2 files changed, 126 insertions, 2 deletions
diff --git a/sys/kern/kern_syscalls.c b/sys/kern/kern_syscalls.c new file mode 100644 index 0000000..e8dc83b --- /dev/null +++ b/sys/kern/kern_syscalls.c @@ -0,0 +1,94 @@ +/*- + * Copyright (c) 1999 Assar Westerlund + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $Id: kern_syscalls.c,v 1.1 1999/01/03 06:00:55 root Exp root $ + */ + +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/malloc.h> +#include <sys/sysproto.h> +#include <sys/sysent.h> +#include <sys/syscall.h> +#include <sys/module.h> +#include <sys/linker.h> +#include <sys/proc.h> + +int +syscall_register(int *offset, struct sysent *new_sysent, + struct sysent *old_sysent) +{ + if (*offset == NO_SYSCALL) { + int i; + + for (i = 1; i < SYS_MAXSYSCALL; ++i) + if (sysent[i].sy_call == (sy_call_t *)lkmnosys) + break; + if (i == SYS_MAXSYSCALL) + return ENFILE; + *offset = i; + } else if (*offset < 0 || *offset >= SYS_MAXSYSCALL) + return EINVAL; + else if (sysent[*offset].sy_call != (sy_call_t *)lkmnosys) + return EEXIST; + + *old_sysent = sysent[*offset]; + sysent[*offset] = *new_sysent; + return 0; +} + +int +syscall_deregister(int *offset, struct sysent *old_sysent) +{ + if (*offset) + sysent[*offset] = *old_sysent; + return 0; +} + +int +syscall_module_handler(struct module *mod, int what, void *arg) +{ + struct syscall_module_data *data = (struct syscall_module_data*)arg; + int error; + + switch (what) { + case MOD_LOAD : + error = syscall_register(data->offset, data->new_sysent, + &data->old_sysent); + if (error) + return error; + break; + case MOD_UNLOAD : + error = syscall_deregister(data->offset, &data->old_sysent); + if (error) + return error; + break; + } + if (data->chainevh) + return data->chainevh(mod, what, data->chainarg); + else + return 0; +} diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h index 114fe35..9bfc978 100644 --- a/sys/sys/sysent.h +++ b/sys/sys/sysent.h @@ -30,7 +30,7 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * $Id: sysent.h,v 1.18 1998/06/07 17:13:03 dfr Exp $ + * $Id: sysent.h,v 1.19 1998/09/14 05:36:51 jdp Exp $ */ #ifndef _SYS_SYSENT_H_ @@ -76,6 +76,36 @@ struct sysentvec { #ifdef KERNEL extern struct sysentvec aout_sysvec; extern struct sysent sysent[]; -#endif + +#define NO_SYSCALL (-1) + +struct module; + +struct syscall_module_data { + int (*chainevh)(struct module *, int, void *); /* next handler */ + void *chainarg; /* arg for next event handler */ + int *offset; /* offset into sysent */ + struct sysent *new_sysent; /* new sysent */ + struct sysent old_sysent; /* old sysent */ +}; + +#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg) \ +static struct syscall_module_data name##_syscall_mod = { \ + evh, arg, offset, new_sysent \ +}; \ + \ +static moduledata_t name##_mod = { \ + #name, \ + syscall_module_handler, \ + &name##_syscall_mod \ +}; \ +DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE) + +int syscall_register __P((int *offset, struct sysent *new_sysent, + struct sysent *old_sysent)); +int syscall_deregister __P((int *offset, struct sysent *old_sysent)); +int syscall_module_handler __P((struct module *mod, int what, void *arg)); + +#endif /* KERNEL */ #endif /* !_SYS_SYSENT_H_ */ |
