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#define __LIBRARY__
#include <unistd.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <asm/segment.h>
#include <sys/stat.h>
#include <fcntl.h>
#define BUF_MAX 4096
#define DIRBUF 8192
#define NAME_MAX 14
struct dirent {
long d_ino;
off_t d_off;
unsigned short d_reclen;
char d_name[NAME_MAX+1];
};
/*参数count指定该缓冲区的大小*/
int sys_getdents(unsigned int fd,struct linux_dirent *dirp,unsigned int count)
{
if(!count)return -1;/*count is zero*/
if(fd>=NR_OPEN)return -EINVAL;/*fd is over range*/
struct file *file;
struct m_inode * inode;
int ret;
struct buffer_head *hd;
struct dir_entry *de;
struct dirent * temp;
char * buf;
int desize,ldsize,i,ldi;
file=current->filp[fd];
if(!file)return ENOTDIR;/*the file is not exist or not file*/
ldsize = sizeof(struct dirent);
desize = sizeof(struct dir_entry);
inode = file ->f_inode;
temp = (struct dirent *)malloc(ldsize);/* //the inter veriable */
buf = (char*)malloc(ldsize);
/*get the inode's bread*/
hd = bread(inode->i_dev , inode->i_zone[0]);
ldi=0;
ret=0;
for (;ret<inode->i_size;ret += desize){
if (ldi >= count-ldsize)
break; /* full */
de = (struct dir_entry *)(hd->b_data + ret);/* de is set to the current dir_entry */
if (!de -> inode )/* to skip if there is no data in de */
continue;
/*To write, copying current dirent, */
temp->d_ino = de->inode;
temp->d_off = 0;
temp->d_reclen = ldsize;
strcpy(temp->d_name,de->name);
/* by put_fs_byte to write back data to the usr */
memcpy(buf, temp, ldsize);
for (i=0;i < ldsize;i++){
put_fs_byte(*(buf+i), ((char*)dirp)+i+ldi);
}
/* memcpy(temp, buf, ldsize); */
ldi += ldsize;
}
return ldi;
}
int do_execve2(unsigned long * eip,long tmp,char * filename,
char ** argv, char ** envp)
{
struct m_inode * inode;
struct buffer_head * bh;
struct exec ex;
unsigned long page[MAX_ARG_PAGES];
int i,argc,envc;
int e_uid, e_gid;
int retval;
int sh_bang = 0;
unsigned long p=PAGE_SIZE*MAX_ARG_PAGES-4;
if ((0xffff & eip[1]) != 0x000f)
panic("execve called from supervisor mode");
for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */
page[i]=0;
if (!(inode=namei(filename))) /* get executables inode */
return -ENOENT;
argc = count(argv);
envc = count(envp);
restart_interp:
if (!S_ISREG(inode->i_mode)) { /* must be regular file */
retval = -EACCES;
goto exec_error2;
}
i = inode->i_mode;
e_uid = (i & S_ISUID) ? inode->i_uid : current->euid;
e_gid = (i & S_ISGID) ? inode->i_gid : current->egid;
if (current->euid == inode->i_uid)
i >>= 6;
else if (current->egid == inode->i_gid)
i >>= 3;
if (!(i & 1) &&
!((inode->i_mode & 0111) && suser())) {
retval = -ENOEXEC;
goto exec_error2;
}
if (!(bh = bread(inode->i_dev,inode->i_zone[0]))) {
retval = -EACCES;
goto exec_error2;
}
ex = *((struct exec *) bh->b_data); /* read exec-header */
if ((bh->b_data[0] == '#') && (bh->b_data[1] == '!') && (!sh_bang)) {
/*
* This section does the #! interpretation.
* Sorta complicated, but hopefully it will work. -TYT
*/
char buf[1023], *cp, *interp, *i_name, *i_arg;
unsigned long old_fs;
strncpy(buf, bh->b_data+2, 1022);
brelse(bh);
iput(inode);
buf[1022] = '\0';
if (cp = strchr(buf, '\n')) {
*cp = '\0';
for (cp = buf; (*cp == ' ') || (*cp == '\t'); cp++);
}
if (!cp || *cp == '\0') {
retval = -ENOEXEC; /* No interpreter name found */
goto exec_error1;
}
interp = i_name = cp;
i_arg = 0;
for ( ; *cp && (*cp != ' ') && (*cp != '\t'); cp++) {
if (*cp == '/')
i_name = cp+1;
}
if (*cp) {
*cp++ = '\0';
i_arg = cp;
}
/*
* OK, we've parsed out the interpreter name and
* (optional) argument.
*/
if (sh_bang++ == 0) {
p = copy_strings(envc, envp, page, p, 0);
p = copy_strings(--argc, argv+1, page, p, 0);
}
/*
* Splice in (1) the interpreter's name for argv[0]
* (2) (optional) argument to interpreter
* (3) filename of shell script
*
* This is done in reverse order, because of how the
* user environment and arguments are stored.
*/
p = copy_strings(1, &filename, page, p, 1);
argc++;
if (i_arg) {
p = copy_strings(1, &i_arg, page, p, 2);
argc++;
}
p = copy_strings(1, &i_name, page, p, 2);
argc++;
if (!p) {
retval = -ENOMEM;
goto exec_error1;
}
/*
* OK, now restart the process with the interpreter's inode.
*/
old_fs = get_fs();
set_fs(get_ds());
if (!(inode=namei(interp))) { /* get executables inode */
set_fs(old_fs);
retval = -ENOENT;
goto exec_error1;
}
set_fs(old_fs);
goto restart_interp;
}
brelse(bh);
if (N_MAGIC(ex) != ZMAGIC || ex.a_trsize || ex.a_drsize ||
ex.a_text+ex.a_data+ex.a_bss>0x3000000 ||
inode->i_size < ex.a_text+ex.a_data+ex.a_syms+N_TXTOFF(ex)) {
retval = -ENOEXEC;
goto exec_error2;
}
if (N_TXTOFF(ex) != BLOCK_SIZE) {
printk("%s: N_TXTOFF != BLOCK_SIZE. See a.out.h.", filename);
retval = -ENOEXEC;
goto exec_error2;
}
if (!sh_bang) {
p = copy_strings(envc,envp,page,p,0);
p = copy_strings(argc,argv,page,p,0);
if (!p) {
retval = -ENOMEM;
goto exec_error2;
}
}
/* OK, This is the point of no return */
if (current->executable)
iput(current->executable);
current->executable = inode;
for (i=0 ; i<32 ; i++)
current->sigaction[i].sa_handler = NULL;
for (i=0 ; i<NR_OPEN ; i++)
if ((current->close_on_exec>>i)&1)
sys_close(i);
current->close_on_exec = 0;
free_page_tables(get_base(current->ldt[1]),get_limit(0x0f));
free_page_tables(get_base(current->ldt[2]),get_limit(0x17));
/*we should rewrite here*/
/**/
if (last_task_used_math == current)
last_task_used_math = NULL;
current->used_math = 0;
p += change_ldt(ex.a_text,page)-MAX_ARG_PAGES*PAGE_SIZE;
p = (unsigned long) create_tables((char *)p,argc,envc);
current->brk = ex.a_bss +
(current->end_data = ex.a_data +
(current->end_code = ex.a_text));
current->start_stack = p & 0xfffff000;
current->euid = e_uid;
current->egid = e_gid;
i = ex.a_text+ex.a_data;
while (i&0xfff)
put_fs_byte(0,(char *) (i++));
eip[0] = ex.a_entry; /* eip, magic happens :-) */
eip[3] = p; /* stack pointer */
return 0;
exec_error2:
iput(inode);
exec_error1:
for (i=0 ; i<MAX_ARG_PAGES ; i++)
free_page(page[i]);
return(retval);
}
int sys_sleep(unsigned int seconds)
{
sys_signal(SIGALRM,SIG_IGN);
sys_alarm(seconds);
if(sys_pause()!=-1)
{
/* printk("sleep\n");*/
return 0;
}
/*printk("do not sleep\n");*/
return -1;
}
/*just full the sys_call_table[89]*/
int sys_something()
{
return 0;
}
/*find the father inode constantly*/
long sys_getcwd(char *buf,size_t size)
{
return 0;
}