diff options
Diffstat (limited to 'syscall.c')
| -rw-r--r-- | syscall.c | 536 |
1 files changed, 19 insertions, 517 deletions
@@ -81,523 +81,25 @@ putint(struct proc *p, uint addr, int x) return 0; } -int -sys_pipe(void) -{ - struct fd *rfd = 0, *wfd = 0; - int f1 = -1, f2 = -1; - struct proc *p = curproc[cpu()]; - uint fdp; - - if(pipe_alloc(&rfd, &wfd) < 0) - goto oops; - if((f1 = fd_ualloc()) < 0) - goto oops; - p->fds[f1] = rfd; - if((f2 = fd_ualloc()) < 0) - goto oops; - p->fds[f2] = wfd; - if(fetcharg(0, &fdp) < 0) - goto oops; - if(putint(p, fdp, f1) < 0) - goto oops; - if(putint(p, fdp+4, f2) < 0) - goto oops; - return 0; - - oops: - if(rfd) - fd_close(rfd); - if(wfd) - fd_close(wfd); - if(f1 >= 0) - p->fds[f1] = 0; - if(f2 >= 0) - p->fds[f2] = 0; - return -1; -} - -int -sys_write(void) -{ - int fd, n, ret; - uint addr; - struct proc *p = curproc[cpu()]; - - if(fetcharg(0, &fd) < 0 || fetcharg(1, &addr) < 0 || fetcharg(2, &n) < 0) - return -1; - if(fd < 0 || fd >= NOFILE) - return -1; - if(p->fds[fd] == 0) - return -1; - if(addr + n > p->sz) - return -1; - - ret = fd_write(p->fds[fd], p->mem + addr, n); - return ret; -} - -int -sys_read(void) -{ - int fd, n, ret; - uint addr; - struct proc *p = curproc[cpu()]; - - if(fetcharg(0, &fd) < 0 || fetcharg(1, &addr) < 0 || fetcharg(2, &n) < 0) - return -1; - if(fd < 0 || fd >= NOFILE) - return -1; - if(p->fds[fd] == 0) - return -1; - if(addr + n > p->sz) - return -1; - ret = fd_read(p->fds[fd], p->mem + addr, n); - return ret; -} - -int -sys_close(void) -{ - int fd; - struct proc *p = curproc[cpu()]; - - if(fetcharg(0, &fd) < 0) - return -1; - if(fd < 0 || fd >= NOFILE) - return -1; - if(p->fds[fd] == 0) - return -1; - fd_close(p->fds[fd]); - p->fds[fd] = 0; - return 0; -} - -int -sys_fork(void) -{ - struct proc *np; - - if((np = copyproc(curproc[cpu()])) == 0) - return -1; - np->state = RUNNABLE; - return np->pid; -} - -int -sys_exit(void) -{ - proc_exit(); - return 0; // not reached -} - -int -sys_wait(void) -{ - return proc_wait(); -} - -int -sys_kill(void) -{ - int pid; - - if(fetcharg(0, &pid) < 0) - return -1; - return proc_kill(pid); -} - -int -sys_open(void) -{ - struct proc *cp = curproc[cpu()]; - struct inode *ip, *dp; - uint arg0, arg1; - int ufd; - struct fd *fd; - int l; - char *last; - - if(fetcharg(0, &arg0) < 0 || fetcharg(1, &arg1) < 0) - return -1; - if((l = checkstring(arg0)) < 0) - return -1; - - if(arg1 & O_CREATE){ - dp = namei(cp->mem + arg0, NAMEI_CREATE, 0, &last, &ip); - if(dp){ - ip = mknod1(dp, last, T_FILE, 0, 0); - iput(dp); - if(ip == 0) - return -1; - } else if(ip == 0){ - return -1; - } else if(ip->type == T_DIR){ - iput(ip); - return -1; - } - } else { - ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0); - if(ip == 0) - return -1; - } - if(ip->type == T_DIR && ((arg1 & O_RDWR) || (arg1 & O_WRONLY))){ - iput(ip); - return -1; - } - - if((fd = fd_alloc()) == 0){ - iput(ip); - return -1; - } - if((ufd = fd_ualloc()) < 0){ - iput(ip); - fd_close(fd); - return -1; - } - - iunlock(ip); - fd->type = FD_FILE; - if(arg1 & O_RDWR) { - fd->readable = 1; - fd->writable = 1; - } else if(arg1 & O_WRONLY) { - fd->readable = 0; - fd->writable = 1; - } else { - fd->readable = 1; - fd->writable = 0; - } - fd->ip = ip; - fd->off = 0; - cp->fds[ufd] = fd; - - return ufd; -} - -int -sys_mknod(void) -{ - struct proc *cp = curproc[cpu()]; - struct inode *nip; - uint arg0, arg1, arg2, arg3; - int l; - - if(fetcharg(0, &arg0) < 0 || fetcharg(1, &arg1) < 0 || - fetcharg(2, &arg2) < 0 || fetcharg(3, &arg3) < 0) - return -1; - - if((l = checkstring(arg0)) < 0) - return -1; - - if(l >= DIRSIZ) - return -1; - - nip = mknod(cp->mem + arg0, (short) arg1, (short) arg2, (short) arg3); - if(nip) - iput(nip); - return (nip == 0) ? -1 : 0; -} - -int -sys_mkdir(void) -{ - struct proc *cp = curproc[cpu()]; - struct inode *nip; - struct inode *dp; - uint arg0; - int l; - struct dirent de; - char *last; - - if(fetcharg(0, &arg0) < 0) - return -1; - - if((l = checkstring(arg0)) < 0) - return -1; - - dp = namei(cp->mem + arg0, NAMEI_CREATE, 0, &last, 0); - if(dp == 0) - return -1; - - nip = mknod1(dp, last, T_DIR, 0, 0); - if(nip == 0){ - iput(dp); - return -1; - } - - dp->nlink += 1; - iupdate(dp); - - memset(de.name, '\0', DIRSIZ); - de.name[0] = '.'; - de.inum = nip->inum; - writei(nip, (char*) &de, 0, sizeof(de)); - - de.inum = dp->inum; - de.name[1] = '.'; - writei(nip, (char*) &de, sizeof(de), sizeof(de)); - - iput(dp); - iput(nip); - - return 0; -} - - -int -sys_chdir(void) -{ - struct proc *cp = curproc[cpu()]; - struct inode *ip; - uint arg0; - int l; - - if(fetcharg(0, &arg0) < 0) - return -1; - - if((l = checkstring(arg0)) < 0) - return -1; - - if((ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0)) == 0) - return -1; - - if(ip == cp->cwd) { - iput(ip); - return 0; - } - - if(ip->type != T_DIR) { - iput(ip); - return -1; - } - - idecref(cp->cwd); - cp->cwd = ip; - iunlock(cp->cwd); - return 0; -} - -int -sys_unlink(void) -{ - struct proc *cp = curproc[cpu()]; - uint arg0; - int r; - - if(fetcharg(0, &arg0) < 0) - return -1; - if(checkstring(arg0) < 0) - return -1; - r = unlink(cp->mem + arg0); - return r; -} - -int -sys_fstat(void) -{ - struct proc *cp = curproc[cpu()]; - uint fd, addr; - int r; - - if(fetcharg(0, &fd) < 0) - return -1; - if(fetcharg(1, &addr) < 0) - return -1; - if(fd < 0 || fd >= NOFILE) - return -1; - if(cp->fds[fd] == 0) - return -1; - if(addr + sizeof(struct stat) > cp->sz) - return -1; - r = fd_stat(cp->fds[fd], (struct stat*)(cp->mem + addr)); - return r; -} - -int -sys_dup(void) -{ - struct proc *cp = curproc[cpu()]; - uint fd, ufd1; - - if(fetcharg(0, &fd) < 0) - return -1; - if(fd < 0 || fd >= NOFILE) - return -1; - if(cp->fds[fd] == 0) - return -1; - if((ufd1 = fd_ualloc()) < 0) - return -1; - cp->fds[ufd1] = cp->fds[fd]; - fd_incref(cp->fds[ufd1]); - return ufd1; -} - -int -sys_link(void) -{ - struct proc *cp = curproc[cpu()]; - uint name1, name2; - int r; - - if(fetcharg(0, &name1) < 0 || checkstring(name1) < 0) - return -1; - if(fetcharg(1, &name2) < 0 || checkstring(name2) < 0) - return -1; - r = link(cp->mem + name1, cp->mem + name2); - return r; -} - -int -sys_getpid(void) -{ - struct proc *cp = curproc[cpu()]; - return cp->pid; -} - - -int -sys_sbrk(void) -{ - uint addr; - int n; - struct proc *cp = curproc[cpu()]; - - if(fetcharg(0, &n) < 0) - return -1; - if((addr = growproc(n)) == 0xffffffff) - return -1; - setupsegs(cp); - return addr; -} - -int -sys_exec(void) -{ - struct proc *cp = curproc[cpu()]; - uint arg0, arg1, sz=0, ap, sp, p1, p2; - int i, nargs, argbytes, len; - struct inode *ip; - struct elfhdr elf; - struct proghdr ph; - char *mem = 0; - - if(fetcharg(0, &arg0) < 0) - return -1; - if(fetcharg(1, &arg1) < 0) - return -1; - if(checkstring(arg0) < 0) - return -1; - ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0); - if(ip == 0) - return -1; - - if(readi(ip, (char*)&elf, 0, sizeof(elf)) < sizeof(elf)) - goto bad; - - if(elf.magic != ELF_MAGIC) - goto bad; - - sz = 0; - for(i = 0; i < elf.phnum; i++){ - if(readi(ip, (char*)&ph, elf.phoff + i * sizeof(ph), - sizeof(ph)) != sizeof(ph)) - goto bad; - if(ph.type != ELF_PROG_LOAD) - continue; - if(ph.memsz < ph.filesz) - goto bad; - sz += ph.memsz; - } - - sz += 4096 - (sz % 4096); - sz += 4096; - - mem = kalloc(sz); - if(mem == 0) - goto bad; - memset(mem, 0, sz); - - // arg1 is a pointer to an array of pointers to string. - nargs = 0; - argbytes = 0; - for(i = 0; ; i++){ - if(fetchint(cp, arg1 + 4*i, &ap) < 0) - goto bad; - if(ap == 0) - break; - len = checkstring(ap); - if(len < 0) - goto bad; - nargs++; - argbytes += len + 1; - } - - // argn\0 - // ... - // arg0\0 - // 0 - // ptr to argn - // ... - // 12: ptr to arg0 - // 8: argv (points to ptr to arg0) - // 4: argc - // 0: fake return pc - sp = sz - argbytes - (nargs+1)*4 - 4 - 4 - 4; - *(uint*)(mem + sp) = 0xffffffff; - *(uint*)(mem + sp + 4) = nargs; - *(uint*)(mem + sp + 8) = (uint)(sp + 12); - - p1 = sp + 12; - p2 = sp + 12 + (nargs + 1) * 4; - for(i = 0; i < nargs; i++){ - fetchint(cp, arg1 + 4*i, &ap); - len = checkstring(ap); - memmove(mem + p2, cp->mem + ap, len + 1); - *(uint*)(mem + p1) = p2; - p1 += 4; - p2 += len + 1; - } - *(uint*)(mem + p1) = 0; - - // commit to the new image. - kfree(cp->mem, cp->sz); - cp->sz = sz; - cp->mem = mem; - mem = 0; - - for(i = 0; i < elf.phnum; i++){ - if(readi(ip, (char*)&ph, elf.phoff + i * sizeof(ph), - sizeof(ph)) != sizeof(ph)) - goto bad2; - if(ph.type != ELF_PROG_LOAD) - continue; - if(ph.va + ph.memsz > sz) - goto bad2; - if(readi(ip, cp->mem + ph.va, ph.offset, ph.filesz) != ph.filesz) - goto bad2; - memset(cp->mem + ph.va + ph.filesz, 0, ph.memsz - ph.filesz); - } - - iput(ip); - - cp->tf->eip = elf.entry; - cp->tf->esp = sp; - setupsegs(cp); - - return 0; - - bad: - if(mem) - kfree(mem, sz); - iput(ip); - return -1; - - bad2: - iput(ip); - proc_exit(); - return 0; -} +extern int sys_chdir(void); +extern int sys_close(void); +extern int sys_dup(void); +extern int sys_exec(void); +extern int sys_exit(void); +extern int sys_fork(void); +extern int sys_fstat(void); +extern int sys_getpid(void); +extern int sys_kill(void); +extern int sys_link(void); +extern int sys_mkdir(void); +extern int sys_mknod(void); +extern int sys_open(void); +extern int sys_pipe(void); +extern int sys_read(void); +extern int sys_sbrk(void); +extern int sys_unlink(void); +extern int sys_wait(void); +extern int sys_write(void); void syscall(void) |