syscalls.c

它通过提供glibc兼容使得应用程序移植到较小的c 库时相当得容易. 它能够应用到带虚拟存储的Linux和uClinux上.在大多数带MMU部件的平台上为使它更加紧凑,它也能够编译成共享库.uClib

int setgid(gid_t gid)
{
	return(__syscall_setgid(gid));
}
#endif

//#define __NR_getgid           47
#ifdef L_getgid
#include <unistd.h>
#if defined (__alpha__)
#define __NR_getgid     __NR_getxgid
#endif
_syscall0(gid_t, getgid);
#endif

//#define __NR_signal           48

//#define __NR_geteuid          49
#ifdef	L_geteuid
#include <unistd.h>
#	ifdef	__NR_geteuid
	_syscall0(uid_t, geteuid);
#	else
	uid_t geteuid(void)
	{
		return (getuid());
	}
#	endif
#endif

//#define __NR_getegid          50
#ifdef	L_getegid
#include <unistd.h>
#	ifdef	__NR_getegid
	_syscall0(gid_t, getegid);
#	else
	gid_t getegid(void)
	{
		return (getgid());
	}
#	endif
#endif

//#define __NR_acct             51
#ifdef L_acct
#include <unistd.h>
_syscall1(int, acct, const char *, filename);
#endif

//#define __NR_umount2          52
#ifdef L_umount2
#	ifdef __NR_umount2 /* Old kernels don't have umount2 */ 
#		include <sys/mount.h>
		_syscall2(int, umount2, const char *, special_file, int, flags);
#	else
		int umount2(const char * special_file, int flags)
		{
			__set_errno(ENOSYS);
			return -1;
		}
#	endif
#endif

//#define __NR_lock             53

//#define __NR_ioctl            54
#ifdef L___syscall_ioctl
#include <stdarg.h>
#include <sys/ioctl.h>
#define __NR___syscall_ioctl __NR_ioctl
extern int __syscall_ioctl(int fd, int request, void *arg);
_syscall3(int, __syscall_ioctl, int, fd, int, request, void *, arg);
#if !defined (__powerpc__)
#include "ioctl.c"
/* Also see ioctl.c and powerpc/ioctl.c */
#endif
#endif

//#define __NR_fcntl            55
#ifdef L__fcntl
#include <stdarg.h>
#include <fcntl.h>
#define __NR__fcntl __NR_fcntl
extern int _fcntl(int fd, int cmd, long arg);

_syscall3(int, _fcntl, int, fd, int, cmd, long, arg);

int __libc_fcntl(int fd, int command, ...)
{
	long arg;
	va_list list;

	va_start(list, command);
	arg = va_arg(list, long);

	va_end(list);
	return _fcntl(fd, command, arg);
}
weak_alias(__libc_fcntl, fcntl)
#endif

//#define __NR_mpx              56

//#define __NR_setpgid          57
#ifdef L___syscall_setpgid
#include <unistd.h>
#define __NR___syscall_setpgid __NR_setpgid
static inline
_syscall2(int, __syscall_setpgid, __kernel_pid_t, pid, __kernel_pid_t, pgid);
int setpgid(pid_t pid, pid_t pgid)
{
	return(__syscall_setpgid(pid, pgid));
}
#endif

//#define __NR_ulimit           58

//#define __NR_oldolduname      59

//#define __NR_umask            60
#ifdef L___syscall_umask
#include <sys/stat.h>
#define __NR___syscall_umask __NR_umask
static inline 
_syscall1(__kernel_mode_t, __syscall_umask, __kernel_mode_t, mask);
mode_t umask(mode_t mask)
{
	return(__syscall_umask(mask));
}
#endif

//#define __NR_chroot           61
#ifdef L_chroot
#include <unistd.h>
_syscall1(int, chroot, const char *, path);
#endif

//#define __NR_ustat            62

//#define __NR_dup2             63
#ifdef L_dup2
#include <unistd.h>
_syscall2(int, dup2, int, oldfd, int, newfd);
#endif

//#define __NR_getppid          64
#ifdef	L_getppid
#	include <unistd.h>
#	ifdef	__NR_getppid
	_syscall0(pid_t, getppid);
#	else
	pid_t getppid(void)
	{
		return (getpid());
	}
#	endif
#endif

//#define __NR_getpgrp          65
#ifdef L_getpgrp
#include <unistd.h>
_syscall0(pid_t, getpgrp);
#endif

//#define __NR_setsid           66
#ifdef L_setsid
#include <unistd.h>
_syscall0(pid_t, setsid);
#endif

//#define __NR_sigaction        67
#ifndef __NR_rt_sigaction
#ifdef L___syscall_sigaction
#define __NR___syscall_sigaction __NR_sigaction
#include <signal.h>
#undef sigaction
_syscall3(int, __syscall_sigaction, int, signum, const struct sigaction *, act,
		  struct sigaction *, oldact);
#endif
#endif

//#define __NR_sgetmask         68

//#define __NR_ssetmask         69

//#define __NR_setreuid         70
#ifdef L___syscall_setreuid
#include <unistd.h>
#define __NR___syscall_setreuid __NR_setreuid
static inline
_syscall2(int, __syscall_setreuid, __kernel_uid_t, ruid, __kernel_uid_t, euid);
int setreuid(uid_t ruid, uid_t euid)
{
	return(__syscall_setreuid(ruid, euid));
}
#endif

//#define __NR_setregid         71
#ifdef L___syscall_setregid
#include <unistd.h>
#define __NR___syscall_setregid __NR_setregid
static inline
_syscall2(int, __syscall_setregid, __kernel_gid_t, rgid, __kernel_gid_t, egid);
int setregid(gid_t rgid, gid_t egid)
{
	return(__syscall_setregid(rgid, egid));
}
#endif

//#define __NR_sigsuspend       72
#ifndef __NR_rt_sigsuspend
#define __NR___sigsuspend __NR_sigsuspend
#ifdef L___sigsuspend
#include <signal.h>
#undef sigsuspend
_syscall3(int, __sigsuspend, int, a, unsigned long int, b, unsigned long int, c);

int sigsuspend (const sigset_t *set)
{
	return __sigsuspend(0, 0, set->__val[0]);
}
#endif
#endif

//#define __NR_sigpending       73
#ifndef __NR_rt_sigpending
#ifdef L_sigpending
#include <signal.h>
#undef sigpending
_syscall1(int, sigpending, sigset_t *, set);
#endif
#endif

//#define __NR_sethostname      74
#ifdef L_sethostname
#include <unistd.h>
_syscall2(int, sethostname, const char *, name, size_t, len);
#endif

//#define __NR_setrlimit        75
#ifndef __NR_ugetrlimit
/* Only wrap setrlimit if the new ugetrlimit is not present */ 
#ifdef L___setrlimit
#define __NR___setrlimit __NR_setrlimit
#include <unistd.h>
#include <sys/resource.h>
#define RMIN(x, y) ((x) < (y) ? (x) : (y))
_syscall2(int, __setrlimit, int, resource, const struct rlimit *, rlim);
int setrlimit (__rlimit_resource_t resource, const struct rlimit *rlimits)
{
	struct rlimit rlimits_small;
	/* We might have to correct the limits values.  Since the old values
	 * were signed the new values might be too large.  */
	rlimits_small.rlim_cur = RMIN ((unsigned long int) rlimits->rlim_cur,
				       RLIM_INFINITY >> 1);
	rlimits_small.rlim_max = RMIN ((unsigned long int) rlimits->rlim_max,
				       RLIM_INFINITY >> 1);
	return(__setrlimit(resource, &rlimits_small));
}
#undef RMIN
#endif
#else /* We don't need to wrap setrlimit */
#ifdef L_setrlimit
#include <unistd.h>
struct rlimit;
_syscall2(int, setrlimit, unsigned int, resource, const struct rlimit *, rlim);
#endif
#endif /* __NR_setrlimit */

//#define __NR_getrlimit        76
#ifdef L___getrlimit
/* Only include the old getrlimit if the new one (ugetrlimit) is not around */ 
#ifndef __NR_ugetrlimit
#define __NR___getrlimit __NR_getrlimit
#include <unistd.h>
#include <sys/resource.h>
_syscall2(int, __getrlimit, int, resource, struct rlimit *, rlim);
int getrlimit (__rlimit_resource_t resource, struct rlimit *rlimits)
{
	int result;
	result = __getrlimit(resource, rlimits);

	if (result == -1)
		return result;

	/* We might have to correct the limits values.  Since the old values
	 * were signed the infinity value is too small.  */
	if (rlimits->rlim_cur == RLIM_INFINITY >> 1)
		rlimits->rlim_cur = RLIM_INFINITY;
	if (rlimits->rlim_max == RLIM_INFINITY >> 1)
		rlimits->rlim_max = RLIM_INFINITY;
	return result;
}
#endif
#endif /* __NR_getrlimit */

//#define __NR_getrusage        77
#ifdef L_getrusage
#include <unistd.h>
#include <wait.h>
_syscall2(int, getrusage, int, who, struct rusage *, usage);
#endif

//#define __NR_gettimeofday     78
#ifdef L_gettimeofday
#include <sys/time.h>
_syscall2(int, gettimeofday, struct timeval *, tv, struct timezone *, tz);
#endif

//#define __NR_settimeofday     79
#ifdef L_settimeofday
#include <sys/time.h>
_syscall2(int, settimeofday, const struct timeval *, tv,
		  const struct timezone *, tz);
#endif

//#define __NR_getgroups        80
#ifdef L___syscall_getgroups
#include <unistd.h>
#define __NR___syscall_getgroups __NR_getgroups
static inline
_syscall2(int, __syscall_getgroups, int, size, __kernel_gid_t *, list);
#define MIN(a,b) (((a)<(b))?(a):(b))
int getgroups(int n, gid_t *groups)
{
	if (unlikely(n < 0)) {
		__set_errno(EINVAL);
		return -1;
	} else {
		int i, ngids;
		__kernel_gid_t kernel_groups[n = MIN(n, sysconf(_SC_NGROUPS_MAX))];
		ngids = __syscall_getgroups(n, kernel_groups);
		if (n != 0 && ngids > 0) {
			for (i = 0; i < ngids; i++) {
				(groups)[i] = kernel_groups[i];
			}
		}
		return ngids;
	}
}
#endif

//#define __NR_setgroups        81
#ifdef L___syscall_setgroups
#include <unistd.h>
#include <grp.h>
#define __NR___syscall_setgroups __NR_setgroups
static inline
_syscall2(int, __syscall_setgroups, size_t, size, const __kernel_gid_t *, list);
int setgroups (size_t n, const gid_t *groups)
{
	if (n > (size_t)sysconf(_SC_NGROUPS_MAX)) {
		__set_errno (EINVAL);
		return -1;
	} else {
		size_t i;
		__kernel_gid_t kernel_groups[n];
		for (i = 0; i < n; i++) {
			kernel_groups[i] = (groups)[i];
			if (groups[i] != (gid_t) ((__kernel_gid_t)groups[i])) {
				__set_errno (EINVAL);
				return -1;
			}
		}
		return(__syscall_setgroups(n, kernel_groups));
	}
}
#endif

//#define __NR_select           82
#ifdef L_select
//Used as a fallback if _newselect isn't available...
#ifndef __NR__newselect
#include <unistd.h>
extern int select(int n, fd_set *readfds, fd_set *writefds, 
		fd_set *exceptfds, struct timeval *timeout);
_syscall5(int, select, int, n, fd_set *, readfds, fd_set *, writefds,
		fd_set *, exceptfds, struct timeval *, timeout);
#endif
#endif

//#define __NR_symlink          83
#ifdef L_symlink
#include <unistd.h>
_syscall2(int, symlink, const char *, oldpath, const char *, newpath);
#endif

//#define __NR_oldlstat         84

//#define __NR_readlink         85
#ifdef L_readlink
#include <unistd.h>
_syscall3(int, readlink, const char *, path, char *, buf, size_t, bufsiz);
#endif

//#define __NR_uselib           86
#ifdef L_uselib
#include <unistd.h>
_syscall1(int, uselib, const char *, library);
#endif

//#define __NR_swapon           87
#ifdef L_swapon
#include <sys/swap.h>
_syscall2(int, swapon, const char *, path, int, swapflags);
#endif

//#define __NR_reboot           88
#ifdef L__reboot
#define __NR__reboot __NR_reboot
extern int _reboot(int magic, int magic2, int flag);

_syscall3(int, _reboot, int, magic, int, magic2, int, flag);

int reboot(int flag)
{
	return (_reboot((int) 0xfee1dead, 672274793, flag));
}
#endif

//#define __NR_readdir          89

//#define __NR_mmap             90
#ifdef L__mmap
#define __NR__mmap __NR_mmap
#include <unistd.h>
#include <sys/mman.h>
extern __ptr_t _mmap(unsigned long *buffer);

_syscall1(__ptr_t, _mmap, unsigned long *, buffer);

__ptr_t mmap(__ptr_t addr, size_t len, int prot,
			 int flags, int fd, __off_t offset)
{
	unsigned long buffer[6];

	buffer[0] = (unsigned long) addr;
	buffer[1] = (unsigned long) len;
	buffer[2] = (unsigned long) prot;
	buffer[3] = (unsigned long) flags;
	buffer[4] = (unsigned long) fd;
	buffer[5] = (unsigned long) offset;
	return (__ptr_t) _mmap(buffer);
}
#endif

//#define __NR_munmap           91
#ifdef L_munmap
#include <unistd.h>
#include <sys/mman.h>
_syscall2(int, munmap, void *, start, size_t, length);
#endif

//#define __NR_truncate         92
#ifdef L_truncate
#include <unistd.h>
_syscall2(int, truncate, const char *, path, __off_t, length);
#endif

//#define __NR_ftruncate        93
#ifdef L_ftruncate
#include <unistd.h>
_syscall2(int, ftruncate, int, fd, __off_t, length);
#endif

//#define __NR_fchmod           94
#ifdef L___syscall_fchmod
#include <sys/stat.h>
#define __NR___syscall_fchmod __NR_fchmod
static inline 
_syscall2(int, __syscall_fchmod, int, fildes, __kernel_mode_t, mode);
int fchmod(int fildes, mode_t mode)
{
	return(__syscall_fchmod(fildes, mode));
}
#endif

//#define __NR_fchown           95
#ifdef L___syscall_fchown
#include <unistd.h>
#define __NR___syscall_fchown __NR_fchown
static inline
_syscall3(int, __syscall_fchown, int, fd, __kernel_uid_t, owner, __kernel_gid_t, group);
int fchown(int fd, uid_t owner, gid_t group)
{
	return(__syscall_fchown(fd, owner, group));
}
#endif

//#define __NR_getpriority      96
#ifdef L___syscall_getpriority
#include <sys/resource.h>
#define __NR___syscall_getpriority __NR_getpriority
_syscall2(int, __syscall_getpriority, __priority_which_t, which, id_t, who);
/* The return value of __syscall_getpriority is biased by this value
 * to avoid returning negative values.  */
#define PZERO 20
int getpriority (enum __priority_which which, id_t who)
{
	int res;

	res = __syscall_getpriority(which, who);
	if (res >= 0)
		res = PZERO - res;
	return res;
}
#endif

//#define __NR_setpriority      97
#ifdef L_setpriority
#include <sys/resource.h>