/* void _sys_msg(const char *s)
{
if ((stderr->_flag & _IOWRITE) && !_error_recursion)
{ _error_recursion = 1;
fprintf(stderr, "\n%s\n", s);
_error_recursion = 0;
}
else
{ _ttywrite((unsigned char *)"\n", 1, 0);
_ttywrite((unsigned char *)s, strlen(s), 0);
_ttywrite((unsigned char *)"\n", 1, 0);
}
}
*/
int _sys_read_(FILEHANDLE fh, unsigned char *buf, int len, int mode)
{
int n = _syscall3(SYS_read, (int)fh, (int)buf, (int)len);
if (n==-1) { /* error condition */
n=0;
}
n = len - n; /* number of bytes NOT read */
if (n!=0) n |= 0x80000000;
return n;
}
FILEHANDLE _sys_open(const char *filename, int openmode)
{ /* nasty magic number interface for openmode */
static int modtab[6] = { /* r = */ O_RDONLY,
/* r+ = */ O_RDWR,
/* w = */ O_WRONLY|O_CREAT|O_TRUNC,
/* w+ = */ O_RDWR |O_TRUNC|O_CREAT,
/* a = */ O_WRONLY|O_CREAT,
/* a+ = */ O_RDWR |O_CREAT|O_APPEND };
char *name = (char *)filename; /* yuk */
FILEHANDLE fh;
openmode = modtab[openmode >> 1]; /* forget the 'b'inary bit */
fh = _syscall3(SYS_open, (int)name, openmode, 0666);
if (fh<0) return NONHANDLE; /* not found */
return fh;
}
extern int system(const char *string)
{
int pid;
void (*s2)(int);
void (*s3)(int);
if ((pid = _vfork()) == 0) {
char *gv[4] = {"sh", "-c", (char*)0, (char*)0};
gv[2] = (char *)string;
_syscall3(SYS_execve, (int)"/bin/sh", (int)gv, (int)_environ);
_syscall1(SYS_exit,127); /* Should not get here!! */
}
s2 = signal(SIGINT, SIG_IGN);
s3 = signal(SIGQUIT, SIG_IGN);
while (1) {
int status;
int wp = _wait(&status);
if (wp == pid || wp == -1) {
signal(SIGINT,s2);
signal(SIGQUIT,s3);
return (wp == -1 ? -1 : status);
}
}
}
//从文件描述符fd中读取count个字节到buf
int32_t read(int32_t fd,void* buf,uint32_t count){
return _syscall3(SYS_READ,fd,buf,count);
}
//将buf中count个字符写入文件描述符fd中
uint32_t write(int32_t fd,const void* buf,uint32_t count){
return _syscall3(SYS_WRITE,fd,buf,count);
}
/* 设置文件偏移量 */
int32_t lseek(int32_t fd, int32_t offset, uint8_t whence) {
return _syscall3(SYS_LSEEK, fd, offset, whence);
}
