iread for T_DEV

O_RDWR, etc. create file

iread for T_DEV
939f9ede · kaashoek · 2601de00 · 939f9ede · 939f9ede · 939f9ede
--- a/fs.c
+++ b/fs.c
@@ -239,6 +239,12 @@ readi(struct inode *ip, void *xdst, uint off, uint n)
  uint target = n, n1;
  struct buf *bp;

+  if (ip->type == T_DEV) {
+    if (ip->major < 0 || ip->major >= NDEV || !devsw[ip->major].d_read)
+      return -1;
+    return devsw[ip->major].d_read (ip->minor, xdst, n);
+  }
+
  while(n > 0 && off < ip->size){
    bp = bread(ip->dev, bmap(ip, off / BSIZE));
    n1 = min(n, ip->size - off);
@@ -257,6 +263,8 @@ int
 writei(struct inode *ip, void *addr, uint n)
 {
  if (ip->type == T_DEV) {
+    if (ip->major < 0 || ip->major >= NDEV || !devsw[ip->major].d_write)
+      return -1;
    return devsw[ip->major].d_write (ip->minor, addr, n);
  } else {
    panic ("writei: unknown type\n");

--- a/fs.h
+++ b/fs.h
@@ -37,3 +37,7 @@ struct dirent {
  char name[DIRSIZ];
 };

+#define O_CREATE  0x200
+#define O_RDONLY  0x000
+#define O_WRONLY  0x001
+#define O_RDWR    0x002
--- a/ide.c
+++ b/ide.c
@@ -58,7 +58,7 @@ void
 ide_intr(void)
 {
  acquire(&ide_lock);
-  cprintf("cpu%d: ide_intr\n", cpu());
+  //  cprintf("cpu%d: ide_intr\n", cpu());
  wakeup(&request[tail]);
  release(&ide_lock);
  lapic_eoi();

--- a/syscall.c
+++ b/syscall.c
@@ -252,18 +252,28 @@ sys_open(void)
  uint arg0, arg1;
  int ufd;
  struct fd *fd;
+  struct inode *dp;
+  int l;

  if(fetcharg(0, &arg0) < 0 || fetcharg(1, &arg1) < 0)
    return -1;
-  if(checkstring(arg0) < 0)
+  if((l = checkstring(arg0)) < 0)
+    return -1;
+  if((ip = namei(cp->mem + arg0)) == 0) {
+    if (arg1 & O_CREATE) {
+      if (l >= DIRSIZ)
+	return -1;
+      dp = iget(rootdev, 1);  // XXX should parse name
+      if (dp->type != T_DIR) 
 	return -1;
-  if((ip = namei(cp->mem + arg0)) == 0)
+      if ((ip = mknod (dp, cp->mem + arg0, T_FILE, 0, 0)) == 0)
 	return -1;
+    } else return -1;
+  }
  if((fd = fd_alloc()) == 0){
    iput(ip);
    return -1;
  }
-
  if((ufd = fd_ualloc()) < 0){
    iput(ip);
    fd_close(fd);
@@ -272,9 +282,12 @@ sys_open(void)

  iunlock(ip);
  fd->type = FD_FILE;
-  if (arg1) {
+  if (arg1 & O_RDWR) {
    fd->readable = 1;
    fd->writeable = 1;
+  } else if (arg1 & O_WRONLY) {
+    fd->readable = 0;
+    fd->writeable = 1;
  } else {
    fd->readable = 1;
    fd->writeable = 0;
@@ -304,13 +317,9 @@ sys_mknod(void)
  if(l >= DIRSIZ)
    return -1;

-  dp = iget(rootdev, 1);
-
-  cprintf("root inode type: %d\n", dp->type);
-
+  dp = iget(rootdev, 1);    // XXX should parse name
  if (dp->type != T_DIR) 
    return -1;
-  
  nip = mknod (dp, cp->mem + arg0, (short) arg1, (short) arg2, 
 		   (short) arg3);


--- a/userfs.c
+++ b/userfs.c
@@ -20,7 +20,7 @@ main(void)
    puts ("mknod failed\n");
  else
    puts ("made a node\n");
-  fd = open("console", 1);
+  fd = open("console", O_WRONLY);
  if(fd >= 0){
    puts("open console ok\n");
  } else {
@@ -45,6 +45,14 @@ main(void)
  } else {
    puts("open doesnotexist failed\n");
  }
+
+  fd = open("doesnotexist", O_CREATE|O_RDWR);
+  if(fd >= 0){
+    puts("creat doesnotexist succeeded\n");
+  } else {
+    puts("error: creat doesnotexist failed!\n");
+  }
+  close(fd);
  //exec("echo", echo_args);
  exec("cat", cat_args);
  return 0;