opendir(3): on success, don't clobber errno

The opendir(3) function was setting errno to ENOTDIR even
when the directory existed and was opened successfully. This
caused git to falsely detect an error.

This change moves the errno assignment into the failure code
block. It also adds a test to test24 to check for errno
changing when opendir(3) returns success.

diff --git a/lib/libc/posix/_opendir.c b/lib/libc/posix/_opendir.c
index 8ede6e60dc71bb842150b5072cb4b539db0e6277..efae29fb152ebf40a13b6b0745bc9b0cc17d7843 100644 (file)
--- a/lib/libc/posix/_opendir.c
+++ b/lib/libc/posix/_opendir.c
@@ -32,12 +32,13 @@ DIR *opendir(const char *name)
 
        /* Check the type again, mark close-on-exec, get a buffer. */
        if (fstat(d, &st) < 0
-               || (errno= ENOTDIR, !S_ISDIR(st.st_mode))
+               || !S_ISDIR(st.st_mode)
                || (f= fcntl(d, F_GETFD)) < 0
                || fcntl(d, F_SETFD, f | FD_CLOEXEC) < 0
                || (dp= (DIR *) malloc(sizeof(*dp))) == nil
        ) {
                int err= errno;
+               if (!S_ISDIR(st.st_mode)) err= ENOTDIR;
                (void) close(d);
                errno= err;
                return nil;

diff --git a/test/test24.c b/test/test24.c
index 44546a906634ff651641a08d5402937ffbf62b08..4b153cabff20beb21e15e96cd47163f7ff7f7802 100644 (file)
--- a/test/test24.c
+++ b/test/test24.c
@@ -73,18 +73,20 @@ void test24a()
 
   if ((fd = dup(0)) != 3) e(1);        /* dup stdin */
   close(fd);                   /* free the fd again */
+  errno= 0;
   dirp = opendir("/");         /* open "/" */
   if (dirp == ((DIR *) NULL)) e(2);    /* has to succseed */
-  if ((fd = dup(0)) <= 2) e(3);        /* dup stdin */
+  if (errno != 0) e(3);        /* success implies errno didn't change */
+  if ((fd = dup(0)) <= 2) e(4);        /* dup stdin */
   if (fd > 3) {                        /* if opendir() uses fd 3 */
        flags = fcntl(3, F_GETFD);      /* get fd fags of 3 */
-       if (!(flags & FD_CLOEXEC)) e(4);        /* it should be closed on */
+       if (!(flags & FD_CLOEXEC)) e(5);        /* it should be closed on */
   }                            /* exec..() calls */
   close(fd);                   /* free the fd again */
   ret = closedir(dirp);                /* close, we don't need it */
-  if (ret == -1) e(5);         /* closedir () unsucces full */
-  if (ret != 0) e(6);          /* should be 0 or -1 */
-  if ((fd = dup(0)) != 3) e(7);        /* see if next fd is same */
+  if (ret == -1) e(6);         /* closedir () unsucces full */
+  if (ret != 0) e(7);          /* should be 0 or -1 */
+  if ((fd = dup(0)) != 3) e(8);        /* see if next fd is same */
   close(fd);                   /* free the fd again */
 
   System("rm -rf foo; mkdir foo");
@@ -93,71 +95,71 @@ void test24a()
   System("rm f[24]");          /* creat `holes' in entrys */
   Chdir("..");
 
-  if ((dirp = opendir("foo")) == ((DIR *) NULL)) e(8); /* open foo */
+  if ((dirp = opendir("foo")) == ((DIR *) NULL)) e(9); /* open foo */
   chk_dir(dirp);               /* test if foo's ok */
   for (j = 0; j < 10; j++) {
        errno = j * 47 % 7;     /* there should */
-       if (readdir(dirp) != DIRENT0) e(9);     /* be nomore dir */
-       if (errno != j * 47 % 7) e(10); /* entrys */
+       if (readdir(dirp) != DIRENT0) e(10);    /* be nomore dir */
+       if (errno != j * 47 % 7) e(11); /* entrys */
   }
   rewinddir(dirp);             /* rewind foo */
   chk_dir(dirp);               /* test foosok */
   for (j = 0; j < 10; j++) {
        errno = j * 23 % 7;     /* there should */
-       if (readdir(dirp) != DIRENT0) e(11);    /* be nomore dir */
-       if (errno != j * 23 % 7) e(12); /* entrys */
+       if (readdir(dirp) != DIRENT0) e(12);    /* be nomore dir */
+       if (errno != j * 23 % 7) e(13); /* entrys */
   }
-  if ((fd4 = creat("foo/f4", 0666)) <= 2) e(13);       /* Open a file. */
+  if ((fd4 = creat("foo/f4", 0666)) <= 2) e(14);       /* Open a file. */
   System("rm foo/f4");         /* Kill entry. */
   rewinddir(dirp);             /* Rewind foo. */
-  if ((fd3 = open("foo/f3", O_WRONLY)) <= 2) e(14);    /* Open more files. */
-  if ((fd5 = open("foo/f5", O_WRONLY)) <= 2) e(15);
-  if (write(fd3, "Hello", 6) != 6) e(16);
-  if (write(fd4, "Hello", 6) != 6) e(17);      /* write some data */
-  if (close(fd5) != 0) e(18);
+  if ((fd3 = open("foo/f3", O_WRONLY)) <= 2) e(15);    /* Open more files. */
+  if ((fd5 = open("foo/f5", O_WRONLY)) <= 2) e(16);
+  if (write(fd3, "Hello", 6) != 6) e(17);
+  if (write(fd4, "Hello", 6) != 6) e(18);      /* write some data */
+  if (close(fd5) != 0) e(19);
   chk_dir(dirp);
   for (j = 0; j < 10; j++) {
        errno = j * 101 % 7;    /* there should */
-       if (readdir(dirp) != DIRENT0) e(19);    /* be nomore dir */
-       if (errno != j * 101 % 7) e(20);        /* entrys */
+       if (readdir(dirp) != DIRENT0) e(20);    /* be nomore dir */
+       if (errno != j * 101 % 7) e(21);        /* entrys */
   }
-  if (close(fd4) != 0) e(21);  /* shouldn't matter */
-  if (close(fd3) != 0) e(22);  /* when we do this */
-  if (closedir(dirp) != 0) e(23);      /* close foo again */
+  if (close(fd4) != 0) e(22);  /* shouldn't matter */
+  if (close(fd3) != 0) e(23);  /* when we do this */
+  if (closedir(dirp) != 0) e(24);      /* close foo again */
 
   Chdir("foo");
-  if ((dirp = opendir(".//")) == ((DIR *) NULL)) e(24);        /* open foo again */
+  if ((dirp = opendir(".//")) == ((DIR *) NULL)) e(25);        /* open foo again */
   Chdir("..");
   chk_dir(dirp);               /* foosok? */
   for (j = 0; j < 10; j++) {
        errno = (j * 101) % 7;  /* there should */
-       if (readdir(dirp) != DIRENT0) e(25);    /* be nomore dir */
-       if (errno != (j * 101) % 7) e(26);      /* entrys */
+       if (readdir(dirp) != DIRENT0) e(26);    /* be nomore dir */
+       if (errno != (j * 101) % 7) e(27);      /* entrys */
   }
 
-  if (closedir(dirp) != 0) e(27);      /* It should be closable */
+  if (closedir(dirp) != 0) e(28);      /* It should be closable */
 
   stat("foo", &st1);           /* get stat */
   time(&time1);
   while (time1 >= time((time_t *)0))
        ;
-  if ((dirp = opendir("foo")) == ((DIR *) NULL)) e(28);        /* open, */
-  if (readdir(dirp) == DIRENT0) e(29); /* read and */
+  if ((dirp = opendir("foo")) == ((DIR *) NULL)) e(29);        /* open, */
+  if (readdir(dirp) == DIRENT0) e(30); /* read and */
   stat("foo", &st2);           /* get new stat */
-  if (st1.st_atime > st2.st_atime) e(30);      /* st_atime check */
+  if (st1.st_atime > st2.st_atime) e(31);      /* st_atime check */
 
   switch (fork()) {
       case -1: printf("Can't fork\n"); break;
       case 0:
        rewinddir(dirp);        /* rewind childs dirp */
-       if (readdir(dirp) == DIRENT0) e(31);    /* read should be ok */
-       if (closedir(dirp) != 0) e(32); /* close child'd foo */
+       if (readdir(dirp) == DIRENT0) e(32);    /* read should be ok */
+       if (closedir(dirp) != 0) e(33); /* close child'd foo */
        exit(0);                /* 0 stops here */
       default:
-       if (wait(&stat_loc) == -1) e(33);       /* PARENT wait()'s */
+       if (wait(&stat_loc) == -1) e(34);       /* PARENT wait()'s */
        break;
   }
-  if (closedir(dirp) != 0) e(34);      /* close parent's foo */
+  if (closedir(dirp) != 0) e(35);      /* close parent's foo */
 }
 
 void test24b()