Opening a directory with O_CREAT should return EISDIR (#23218)

So that the behavior matches the behavior on linux. This makes the test
pass on nodefs and noderawfs. This allows merging the test added in
#23137 into test_fcntl_open.c

Author: hoodmane

src/library_fs.js

@@ -426,8 +426,8 @@ FS.staticInit();
       if (FS.isLink(node.mode)) {
         return {{{ cDefs.ELOOP }}};
       } else if (FS.isDir(node.mode)) {
-        if (FS.flagsToPermissionString(flags) !== 'r' || // opening for write
-            (flags & {{{ cDefs.O_TRUNC }}})) { // TODO: check for O_SEARCH? (== search for dir only)
+        if (FS.flagsToPermissionString(flags) !== 'r' // opening for write
+            || (flags & ({{{ cDefs.O_TRUNC }}} | {{{ cDefs.O_CREAT }}}))) { // TODO: check for O_SEARCH? (== search for dir only)
           return {{{ cDefs.EISDIR }}};
         }
       }

system/lib/wasmfs/syscalls.cpp

@@ -520,7 +520,7 @@ static __wasi_fd_t doOpen(path::ParsedParent parsed,
     return -EEXIST;
   }
 
-  if (child->is<Directory>() && accessMode != O_RDONLY) {
+  if (child->is<Directory>() && (accessMode != O_RDONLY || (flags & O_CREAT))) {
     return -EISDIR;
   }
 

test/fcntl/test_fcntl_open.c

@@ -78,7 +78,7 @@ void test() {
       if ((flags & O_CREAT) && (flags & O_EXCL)) {
         assert(!success);
         assert(errno == EEXIST);
-      } else if ((flags & O_TRUNC) || i != 0 /*mode != O_RDONLY*/) {
+      } else if ((flags & O_TRUNC) || i != 0 /*mode != O_RDONLY*/ || (flags & O_CREAT)) {
         assert(!success);
         assert(errno == EISDIR);
       } else {

test/fcntl/test_fcntl_open.out

@@ -19,8 +19,8 @@ errno: 0
 st_mode: 0100000
 
 EXISTING FOLDER 0,1
-success: 1
-errno: 0
+success: 0
+errno: 31
 st_mode: 040000
 
 NON-EXISTING 0,1
@@ -139,8 +139,8 @@ errno: 0
 st_mode: 0100000
 
 EXISTING FOLDER 0,9
-success: 1
-errno: 0
+success: 0
+errno: 31
 st_mode: 040000
 
 NON-EXISTING 0,9
@@ -259,8 +259,8 @@ errno: 0
 st_mode: 0100000
 
 EXISTING FOLDER 0,17
-success: 1
-errno: 0
+success: 0
+errno: 31
 st_mode: 040000
 
 NON-EXISTING 0,17
@@ -379,8 +379,8 @@ errno: 0
 st_mode: 0100000
 
 EXISTING FOLDER 0,25
-success: 1
-errno: 0
+success: 0
+errno: 31
 st_mode: 040000
 
 NON-EXISTING 0,25

test/other/codesize/test_codesize_cxx_ctors1.gzsize

@@ -1 +1 @@
-8407
+8408

test/other/codesize/test_codesize_cxx_ctors2.gzsize

@@ -1 +1 @@
-8390
+8392

test/other/codesize/test_codesize_cxx_except.gzsize

@@ -1 +1 @@
-9411
+9413

test/other/codesize/test_codesize_cxx_except_wasm.gzsize

@@ -1 +1 @@
-8373
+8374

test/other/codesize/test_codesize_cxx_except_wasm_exnref.gzsize

@@ -1 +1 @@
-8373
+8374

test/other/codesize/test_codesize_cxx_lto.gzsize

@@ -1 +1 @@
-8404
+8406