From 7ee786388ae0d6f8c8cea7bf012cc11fdb5b534a Mon Sep 17 00:00:00 2001
From: Yuta Saito <kateinoigakukun@gmail.com>
Date: Sun, 16 Jan 2022 01:18:49 +0900
Subject: [PATCH] [wasm] wasm/missing.{c,h}: add missing libc stubs for
 wasi-libc

---
 configure.ac           |  23 +++++
 include/ruby/missing.h | 113 +++++++++++++++++++++++
 io.c                   |   1 +
 missing/flock.c        |   7 ++
 wasm/GNUmakefile.in    |   1 +
 wasm/missing.c         | 199 +++++++++++++++++++++++++++++++++++++++++
 6 files changed, 344 insertions(+)
 create mode 100644 wasm/missing.c

diff --git a/configure.ac b/configure.ac
index c08889c803..f6f88901bd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1232,6 +1232,9 @@ main()
 		RUBY_APPEND_OPTIONS(CFLAGS, -D_WASI_EMULATED_SIGNAL -D_WASI_EMULATED_MMAN -D_WASI_EMULATED_GETPID -D_WASI_EMULATED_PROCESS_CLOCKS)
 		RUBY_APPEND_OPTIONS(CPPFLAGS, -D_WASI_EMULATED_SIGNAL -D_WASI_EMULATED_MMAN -D_WASI_EMULATED_GETPID -D_WASI_EMULATED_PROCESS_CLOCKS)
 		POSTLINK="\$(WASMOPT) --asyncify \$(wasmoptflags) --pass-arg=asyncify-ignore-imports -o \$@ \$@${POSTLINK:+; $POSTLINK}"
+		# wasi-libc's sys/socket.h is not compatible with -std=gnu99,
+		# so re-declare shutdown in include/ruby/missing.h
+		ac_cv_func_shutdown=no
 		]
 [	LIBS="-lm $LIBS"])
 : ${ORIG_LIBS=$LIBS}
@@ -1294,6 +1297,7 @@ AC_CHECK_HEADERS(sanitizer/asan_interface.h)
 AC_CHECK_HEADERS(sanitizer/msan_interface.h)
 AC_CHECK_HEADERS(setjmpex.h)
 AC_CHECK_HEADERS(stdalign.h)
+AC_CHECK_HEADERS(stdio.h)
 AC_CHECK_HEADERS(sys/attr.h)
 AC_CHECK_HEADERS(sys/eventfd.h)
 AC_CHECK_HEADERS(sys/fcntl.h)
@@ -1967,6 +1971,8 @@ AC_CHECK_FUNCS(_longjmp)		# used for AC_ARG_WITH(setjmp-type)
 test x$ac_cv_func__longjmp = xno && ac_cv_func__setjmp=no
 AC_CHECK_FUNCS(arc4random_buf)
 AC_CHECK_FUNCS(atan2l atan2f)
+AC_CHECK_FUNCS(chmod)
+AC_CHECK_FUNCS(chown)
 AC_CHECK_FUNCS(chroot)
 AC_CHECK_FUNCS(chsize)
 AC_CHECK_FUNCS(clock_gettime)
@@ -1982,6 +1988,9 @@ AC_CHECK_FUNCS(dup3)
 AC_CHECK_FUNCS(eaccess)
 AC_CHECK_FUNCS(endgrent)
 AC_CHECK_FUNCS(eventfd)
+AC_CHECK_FUNCS(execl)
+AC_CHECK_FUNCS(execle)
+AC_CHECK_FUNCS(execve)
 AC_CHECK_FUNCS(explicit_memset)
 AC_CHECK_FUNCS(fcopyfile)
 AC_CHECK_FUNCS(fchmod)
@@ -1997,7 +2006,10 @@ AC_CHECK_FUNCS(ftruncate)
 AC_CHECK_FUNCS(ftruncate64)		# used for Win32 platform
 AC_CHECK_FUNCS(getattrlist)
 AC_CHECK_FUNCS(getcwd)
+AC_CHECK_FUNCS(getegid)
 AC_CHECK_FUNCS(getentropy)
+AC_CHECK_FUNCS(geteuid)
+AC_CHECK_FUNCS(getgid)
 AC_CHECK_FUNCS(getgidx)
 AC_CHECK_FUNCS(getgrnam)
 AC_CHECK_FUNCS(getgrnam_r)
@@ -2006,6 +2018,7 @@ AC_CHECK_FUNCS(getlogin)
 AC_CHECK_FUNCS(getlogin_r)
 AC_CHECK_FUNCS(getpgid)
 AC_CHECK_FUNCS(getpgrp)
+AC_CHECK_FUNCS(getppid)
 AC_CHECK_FUNCS(getpriority)
 AC_CHECK_FUNCS(getpwnam)
 AC_CHECK_FUNCS(getpwnam_r)
@@ -2017,6 +2030,7 @@ AC_CHECK_FUNCS(getresuid)
 AC_CHECK_FUNCS(getrlimit)
 AC_CHECK_FUNCS(getsid)
 AC_CHECK_FUNCS(gettimeofday)		# for making ac_cv_func_gettimeofday
+AC_CHECK_FUNCS(getuid)
 AC_CHECK_FUNCS(getuidx)
 AC_CHECK_FUNCS(gmtime_r)
 AC_CHECK_FUNCS(grantpt)
@@ -2024,6 +2038,7 @@ AC_CHECK_FUNCS(initgroups)
 AC_CHECK_FUNCS(ioctl)
 AC_CHECK_FUNCS(isfinite)
 AC_CHECK_FUNCS(issetugid)
+AC_CHECK_FUNCS(kill)
 AC_CHECK_FUNCS(killpg)
 AC_CHECK_FUNCS(lchmod)
 AC_CHECK_FUNCS(lchown)
@@ -2047,9 +2062,13 @@ AC_CHECK_FUNCS(mktime)
 AC_CHECK_FUNCS(mmap)
 AC_CHECK_FUNCS(mremap)
 AC_CHECK_FUNCS(openat)
+AC_CHECK_FUNCS(pclose)
+AC_CHECK_FUNCS(pipe)
 AC_CHECK_FUNCS(pipe2)
 AC_CHECK_FUNCS(poll)
+AC_CHECK_FUNCS(popen)
 AC_CHECK_FUNCS(posix_fadvise)
+AC_CHECK_FUNCS(posix_madvise)
 AC_CHECK_FUNCS(posix_memalign)
 AC_CHECK_FUNCS(ppoll)
 AC_CHECK_FUNCS(pread)
@@ -2088,12 +2107,15 @@ AC_CHECK_FUNCS(spawnv)
 AC_CHECK_FUNCS(symlink)
 AC_CHECK_FUNCS(syscall)
 AC_CHECK_FUNCS(sysconf)
+AC_CHECK_FUNCS(system)
 AC_CHECK_FUNCS(tanh)
 AC_CHECK_FUNCS(telldir)
 AC_CHECK_FUNCS(timegm)
 AC_CHECK_FUNCS(times)
 AC_CHECK_FUNCS(truncate)
 AC_CHECK_FUNCS(truncate64)		# used for Win32
+AC_CHECK_FUNCS(tzset)
+AC_CHECK_FUNCS(umask)
 AC_CHECK_FUNCS(unsetenv)
 AC_CHECK_FUNCS(utimensat)
 AC_CHECK_FUNCS(utimes)
@@ -3807,6 +3829,7 @@ AS_CASE(["$target_os"],
 	],
     [wasi*], [
         FIRSTMAKEFILE=GNUmakefile:wasm/GNUmakefile.in
+        AC_LIBOBJ([wasm/missing])
         AC_LIBOBJ([wasm/runtime])
         AC_LIBOBJ([wasm/fiber])
         AC_LIBOBJ([wasm/machine])
diff --git a/include/ruby/missing.h b/include/ruby/missing.h
index 1e97e294f1..aea6c9088d 100644
--- a/include/ruby/missing.h
+++ b/include/ruby/missing.h
@@ -33,6 +33,18 @@
 # include <sys/time.h>
 #endif
 
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#ifdef HAVE_STDIO_H
+# include <stdio.h>
+#endif
+
 #ifdef HAVE_IEEEFP_H
 # include <ieeefp.h>
 #endif
@@ -224,6 +236,107 @@ RUBY_EXTERN void setproctitle(const char *fmt, ...);
 RUBY_EXTERN void explicit_bzero(void *b, size_t len);
 #endif
 
+#ifndef HAVE_TZSET
+RUBY_EXTERN void tzset(void);
+#endif
+
+#ifndef HAVE_POSIX_MADVISE
+RUBY_EXTERN int posix_madvise(void *, size_t, int);
+#endif
+
+#ifndef HAVE_GETEUID
+RUBY_EXTERN rb_uid_t geteuid(void);
+#endif
+
+#ifndef HAVE_GETUID
+RUBY_EXTERN rb_uid_t getuid(void);
+#endif
+
+#ifndef HAVE_GETEGID
+RUBY_EXTERN rb_gid_t getegid(void);
+#endif
+
+#ifndef HAVE_GETGID
+RUBY_EXTERN rb_gid_t getgid(void);
+#endif
+
+#ifndef HAVE_GETLOGIN
+RUBY_EXTERN char *getlogin(void);
+#endif
+
+#ifndef HAVE_GETPPID
+RUBY_EXTERN rb_pid_t getppid(void);
+#endif
+
+#ifndef HAVE_UMASK
+RUBY_EXTERN rb_mode_t umask(rb_mode_t);
+#endif
+
+#ifndef HAVE_CHMOD
+RUBY_EXTERN int chmod(const char *, rb_mode_t);
+#endif
+
+#ifndef HAVE_CHOWN
+RUBY_EXTERN int chown(const char *, rb_uid_t, rb_gid_t);
+#endif
+
+#ifndef HAVE_PCLOSE
+RUBY_EXTERN int pclose(FILE *);
+#endif
+
+#ifndef HAVE_POPEN
+RUBY_EXTERN FILE *popen(const char *, const char *);
+#endif
+
+#ifndef HAVE_PIPE
+RUBY_EXTERN int pipe(int [2]);
+#endif
+
+#ifndef HAVE_DUP
+RUBY_EXTERN int dup(int);
+#endif
+
+#ifndef HAVE_DUP2
+RUBY_EXTERN int dup2(int, int);
+#endif
+
+#ifndef HAVE_KILL
+RUBY_EXTERN int kill(rb_pid_t, int);
+#endif
+
+#ifndef HAVE_EXECL
+RUBY_EXTERN int execl(const char *, const char *, ...);
+#endif
+
+#ifndef HAVE_EXECLE
+RUBY_EXTERN int execle(const char *, const char *, ...);
+#endif
+
+#ifndef HAVE_EXECV
+RUBY_EXTERN int execv(const char *, char *const []);
+#endif
+
+#ifndef HAVE_EXECVE
+RUBY_EXTERN int execve(const char *, char *const [], char *const []);
+#endif
+
+#ifndef HAVE_SHUTDOWN
+RUBY_EXTERN int shutdown(int, int);
+#endif
+
+#ifndef HAVE_SYSTEM
+RUBY_EXTERN int system(const char *);
+#endif
+
+#ifndef WNOHANG
+# define WNOHANG 0
+#endif
+
+#ifndef HAVE_WAITPID
+# define HAVE_WAITPID 1
+RUBY_EXTERN rb_pid_t waitpid(rb_pid_t, int *, int);
+#endif
+
 RBIMPL_SYMBOL_EXPORT_END()
 
 #endif /* RUBY_MISSING_H */
diff --git a/io.c b/io.c
index 237bb9becc..e278f25cad 100644
--- a/io.c
+++ b/io.c
@@ -133,6 +133,7 @@
 #include "internal/variable.h"
 #include "ruby/io.h"
 #include "ruby/io/buffer.h"
+#include "ruby/missing.h"
 #include "ruby/thread.h"
 #include "ruby/util.h"
 #include "ruby_atomic.h"
diff --git a/missing/flock.c b/missing/flock.c
index c0b3f80601..9daf1c38cc 100644
--- a/missing/flock.c
+++ b/missing/flock.c
@@ -2,6 +2,13 @@
 #include "ruby/ruby.h"
 
 #if defined _WIN32
+#elif defined __wasi__
+#include <errno.h>
+
+int flock(int fd, int operation) {
+  errno = EINVAL;
+  return -1;
+}
 #elif defined HAVE_FCNTL && defined HAVE_FCNTL_H
 
 /* These are the flock() constants.  Since this systems doesn't have
diff --git a/wasm/GNUmakefile.in b/wasm/GNUmakefile.in
index b3b427e023..4328dec9c6 100644
--- a/wasm/GNUmakefile.in
+++ b/wasm/GNUmakefile.in
@@ -8,6 +8,7 @@ wasmoptflags = @wasmoptflags@
 
 WASM_OBJS  = $(wasmdir)/machine_core.o $(wasmdir)/machine.o $(wasmdir)/setjmp.o $(wasmdir)/setjmp_core.o $(wasmdir)/fiber.o $(wasmdir)/runtime.o
 
+wasm/missing.$(OBJEXT): $(wasmdir)/missing.c $(PLATFORM_D)
 wasm/fiber.$(OBJEXT): $(wasmdir)/fiber.c $(wasmdir)/fiber.h $(wasmdir)/asyncify.h $(PLATFORM_D)
 wasm/machine.$(OBJEXT): $(wasmdir)/machine.c $(srcdir)/wasm/machine.h $(wasmdir)/asyncify.h $(PLATFORM_D)
 wasm/setjmp.$(OBJEXT): $(wasmdir)/setjmp.c $(wasmdir)/setjmp.h $(wasmdir)/machine.h $(wasmdir)/asyncify.h $(PLATFORM_D)
diff --git a/wasm/missing.c b/wasm/missing.c
new file mode 100644
index 0000000000..5bbf988642
--- /dev/null
+++ b/wasm/missing.c
@@ -0,0 +1,199 @@
+#include <errno.h>
+#include <sys/types.h>
+#include "ruby/missing.h"
+
+// Produce weak symbols for missing functions to replace them with actual ones if exists.
+#define WASM_MISSING_LIBC_FUNC __attribute__((weak))
+
+WASM_MISSING_LIBC_FUNC
+int
+chmod(const char *pathname, rb_mode_t mode)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+chown(const char *pathname, rb_uid_t owner, rb_gid_t group)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+dup(int oldfd)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+dup2(int oldfd, int newfd)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+execl(const char *path, const char *arg, ...)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+execle(const char *path, const char *arg, ...)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+execv(const char *path, char *const argv[])
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+execve(const char *filename, char *const argv[], char *const envp[])
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_uid_t
+geteuid(void)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_uid_t
+getuid(void)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_pid_t
+getppid(void)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_gid_t
+getegid(void)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_gid_t
+getgid(void)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+char *
+getlogin(void)
+{
+    errno = ENOTSUP;
+    return NULL;
+}
+
+WASM_MISSING_LIBC_FUNC
+rb_mode_t
+umask(rb_mode_t mask)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+mprotect(const void *addr, size_t len, int prot)
+{
+    return 0;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+pclose(FILE *stream)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+FILE *
+popen(const char *command, const char *type)
+{
+    errno = ENOTSUP;
+    return NULL;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+pipe(int pipefd[2])
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+posix_madvise(void *addr, size_t len, int advice)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+kill(rb_pid_t pid, int sig)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+
+WASM_MISSING_LIBC_FUNC
+void
+tzset(void)
+{
+    return;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+shutdown(int s, int how)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+int
+system(const char *command)
+{
+    errno = ENOTSUP;
+    return -1;
+}
+
+WASM_MISSING_LIBC_FUNC
+pid_t
+waitpid(pid_t pid, int *wstatus, int options)
+{
+    errno = ENOTSUP;
+    return -1;
+}