mkdir check error from mknod

chdir return -1 if target not a dir

mkdir check error from mknod
a6c28c97 · rtm · a84585de · a6c28c97 · a6c28c97 · a6c28c97
--- a/Notes
+++ b/Notes
@@ -114,17 +114,10 @@ why does shell often ignore first line of input?

 test: one process unlinks a file while another links to it
 test: one process opens a file while another deletes it
-test: mkdir. deadlock d/.. vs ../d
-test: sub-sub directories. mkdir("d1/d2")
+test: mkdir. deadlock d/.. vs ../d, two processes.
 test: dup() shared fd->off
-test: indirect blocks. files and directories.
 test: sbrk
 test: does echo foo > x truncate x?
-test: does create/mkdir/link extract last component correctly?
-      does namei insist that all the intermediate directories exist?
-test: creat/link/mkdir w/ / in name
-test: try to create dir ents when intermediate dir doesn't exist
-      or is a file, not a dir   

 make proc[0] runnable
 cpu early tss and gdt

--- a/fstests.c
+++ b/fstests.c
@@ -450,6 +450,19 @@ subdir()
    exit();
  }

+  if(chdir("dd") != 0){
+    puts("chdir dd failed\n");
+    exit();
+  }
+  if(chdir("dd/../../dd") != 0){
+    puts("chdir dd/../../dd failed\n");
+    exit();
+  }
+  if(chdir("./..") != 0){
+    puts("chdir ./.. failed\n");
+    exit();
+  }
+
  fd = open("dd/dd/ffff", 0);
  if(fd < 0){
    puts("open dd/dd/ffff failed\n");
@@ -506,6 +519,14 @@ subdir()
    puts("unlink dd/ff/ff succeeded!\n");
    exit();
  }
+  if(chdir("dd/ff") == 0){
+    puts("chdir dd/ff succeeded!\n");
+    exit();
+  }
+  if(chdir("dd/xx") == 0){
+    puts("chdir dd/xx succeeded!\n");
+    exit();
+  }

  if(unlink("dd/dd/ffff") != 0){
    puts("unlink dd/dd/ff failed\n");
@@ -522,11 +543,66 @@ subdir()
  puts("subdir ok\n");
 }

+void
+bigfile()
+{
+  int fd, i, total, cc;
+
+  unlink("bigfile");
+  fd = open("bigfile", O_CREATE | O_RDWR);
+  if(fd < 0){
+    puts("cannot create bigfile");
+    exit();
+  }
+  for(i = 0; i < 20; i++){
+    memset(buf, i, 600);
+    if(write(fd, buf, 600) != 600){
+      puts("write bigfile failed\n");
+      exit();
+    }
+  }
+  close(fd);
+  
+  fd = open("bigfile", 0);
+  if(fd < 0){
+    puts("cannot open bigfile\n");
+    exit();
+  }
+  total = 0;
+  for(i = 0; ; i++){
+    cc = read(fd, buf, 300);
+    if(cc < 0){
+      puts("read bigfile failed\n");
+      exit();
+    }
+    if(cc == 0)
+      break;
+    if(cc != 300){
+      puts("short read bigfile\n");
+      exit();
+    }
+    if(buf[0] != i/2 || buf[299] != i/2){
+      puts("read bigfile wrong data\n");
+      exit();
+    }
+    total += cc;
+  }
+  close(fd);
+  if(total != 20*600){
+    puts("read bigfile wrong total\n");
+    exit();
+  }
+  unlink("bigfile");
+
+  puts("bigfile ok\n");
+}
+
 int
 main(int argc, char *argv[])
 {
  puts("fstests starting\n");

+  bigfile();
  subdir();
  // bigdir(); // slow
  concreate();

--- a/syscall.c
+++ b/syscall.c
@@ -320,6 +320,8 @@ sys_mkdir(void)
    return -1;

  nip = mknod (cp->mem + arg0, T_DIR, 0, 0);
+  if(nip == 0)
+    return -1;
  
  memset (de.name, '\0', DIRSIZ);
  de.name[0] = '.';
@@ -364,7 +366,7 @@ sys_chdir(void)

  if (ip->type != T_DIR) {
    iput(ip);
-    return 0;
+    return -1;
  }

  idecref(cp->cwd);