add __WASI_FILETYPE_FIFO type

snapshot_preview2 added support for FIFO types. Prior to this,
FIFOs were treated as sockets and unknown files.

Refs: #59

Author: cjihrig

README.md

@@ -1859,6 +1859,10 @@ Possible values:
 
     The file refers to a symbolic link inode.
 
+- <a href="#filetype.fifo" name="filetype.fifo"></a>**`UVWASI_FILETYPE_FIFO`**
+
+    The file descriptor or file refers to a FIFO.
+
 ### <a href="#fstflags" name="fstflags"></a>`uvwasi_fstflags_t` (`uint16_t` bitfield)
 
 Which file time attributes to adjust.

include/wasi_types.h

@@ -141,6 +141,7 @@ typedef uint8_t uvwasi_filetype_t;
 #define UVWASI_FILETYPE_SOCKET_DGRAM     5
 #define UVWASI_FILETYPE_SOCKET_STREAM    6
 #define UVWASI_FILETYPE_SYMBOLIC_LINK    7
+#define UVWASI_FILETYPE_FIFO             8
 
 typedef uint16_t uvwasi_fstflags_t;              /* Bitfield */
 #define UVWASI_FILESTAT_SET_ATIM      (1 << 0)

src/uv_mapping.c

@@ -134,7 +134,7 @@ uvwasi_filetype_t uvwasi__stat_to_filetype(const uv_stat_t* stat) {
 
 #ifdef S_ISFIFO
   if (S_ISFIFO(mode))
-    return UVWASI_FILETYPE_SOCKET_STREAM;
+    return UVWASI_FILETYPE_FIFO;
 #endif /* S_ISFIFO */
 
 #ifdef S_ISBLK

src/uvwasi.c

@@ -1455,6 +1455,8 @@ uvwasi_errno_t uvwasi_fd_readdir(uvwasi_t* uvwasi,
           dirent.d_type = UVWASI_FILETYPE_BLOCK_DEVICE;
           break;
         case UV_DIRENT_FIFO:
+          dirent.d_type = UVWASI_FILETYPE_FIFO;
+          break;
         case UV_DIRENT_UNKNOWN:
         default:
           dirent.d_type = UVWASI_FILETYPE_UNKNOWN;

src/wasi_rights.c

@@ -45,6 +45,11 @@ uvwasi_errno_t uvwasi__get_rights(uv_file fd,
       *rights_inheriting = UVWASI__RIGHTS_BLOCK_DEVICE_INHERITING;
       break;
 
+    case UVWASI_FILETYPE_FIFO:
+      *rights_base = UVWASI__RIGHTS_FIFO_BASE;
+      *rights_inheriting = UVWASI__RIGHTS_FIFO_INHERITING;
+      break;
+
     default:
       *rights_base = 0;
       *rights_inheriting = 0;

src/wasi_rights.h

@@ -93,6 +93,13 @@
                                  UVWASI_RIGHT_POLL_FD_READWRITE)
 #define UVWASI__RIGHTS_TTY_INHERITING 0
 
+#define UVWASI__RIGHTS_FIFO_BASE (UVWASI_RIGHT_FD_READ |                      \
+                                  UVWASI_RIGHT_FD_FDSTAT_SET_FLAGS |          \
+                                  UVWASI_RIGHT_FD_WRITE |                     \
+                                  UVWASI_RIGHT_FD_FILESTAT_GET |              \
+                                  UVWASI_RIGHT_POLL_FD_READWRITE)
+#define UVWASI__RIGHTS_FIFO_INHERITING UVWASI__RIGHTS_ALL
+
 
 uvwasi_errno_t uvwasi__get_rights(uv_file fd,
                                   int flags,