Added basic support for wasm32-emscripten target

lib/std/c/emscripten.zig

@@ -1,3 +1,169 @@
+const std = @import("../std.zig");
+const maxInt = std.math.maxInt;
+const emscripten = std.os.emscripten;
+
+pub const AF = emscripten.AF;
+pub const AT = emscripten.AT;
+pub const CLOCK = emscripten.CLOCK;
+pub const CPU_COUNT = emscripten.CPU_COUNT;
+pub const E = emscripten.E;
+pub const F = emscripten.F;
+pub const FD_CLOEXEC = emscripten.FD_CLOEXEC;
+pub const F_OK = emscripten.F_OK;
+pub const Flock = emscripten.Flock;
+pub const IFNAMESIZE = emscripten.IFNAMESIZE;
+pub const IOV_MAX = emscripten.IOV_MAX;
+pub const IPPROTO = emscripten.IPPROTO;
+pub const LOCK = emscripten.LOCK;
+pub const MADV = emscripten.MADV;
+pub const MAP = struct {
+    pub usingnamespace emscripten.MAP;
+    /// Only used by libc to communicate failure.
+    pub const FAILED = @as(*anyopaque, @ptrFromInt(maxInt(usize)));
+};
+pub const MSF = emscripten.MSF;
+pub const MSG = emscripten.MSG;
+pub const NAME_MAX = emscripten.NAME_MAX;
+pub const O = emscripten.O;
+pub const PATH_MAX = emscripten.PATH_MAX;
+pub const POLL = emscripten.POLL;
+pub const PROT = emscripten.PROT;
+pub const REG = emscripten.REG;
+pub const RLIM = emscripten.RLIM;
+pub const R_OK = emscripten.R_OK;
+pub const S = emscripten.S;
+pub const SA = emscripten.SA;
+pub const SEEK = emscripten.SEEK;
+pub const SHUT = emscripten.SHUT;
+pub const SIG = emscripten.SIG;
+pub const SIOCGIFINDEX = emscripten.SIOCGIFINDEX;
+pub const SO = emscripten.SO;
+pub const SOCK = emscripten.SOCK;
+pub const SOL = emscripten.SOL;
+pub const STDERR_FILENO = emscripten.STDERR_FILENO;
+pub const STDIN_FILENO = emscripten.STDIN_FILENO;
+pub const STDOUT_FILENO = emscripten.STDOUT_FILENO;
+pub const Sigaction = emscripten.Sigaction;
+pub const TCP = emscripten.TCP;
+pub const TCSA = emscripten.TCSA;
+pub const W = emscripten.W;
+pub const W_OK = emscripten.W_OK;
+pub const X_OK = emscripten.X_OK;
+pub const addrinfo = emscripten.addrinfo;
+pub const blkcnt_t = emscripten.blkcnt_t;
+pub const blksize_t = emscripten.blksize_t;
+pub const clock_t = emscripten.clock_t;
+pub const cpu_set_t = emscripten.cpu_set_t;
+pub const dev_t = emscripten.dev_t;
+pub const dl_phdr_info = emscripten.dl_phdr_info;
+pub const empty_sigset = emscripten.empty_sigset;
+pub const fd_t = emscripten.fd_t;
+pub const gid_t = emscripten.gid_t;
+pub const ifreq = emscripten.ifreq;
+pub const ino_t = emscripten.ino_t;
+pub const mcontext_t = emscripten.mcontext_t;
+pub const mode_t = emscripten.mode_t;
+pub const msghdr = emscripten.msghdr;
+pub const msghdr_const = emscripten.msghdr_const;
+pub const nfds_t = emscripten.nfds_t;
+pub const nlink_t = emscripten.nlink_t;
+pub const off_t = emscripten.off_t;
+pub const pid_t = emscripten.pid_t;
+pub const pollfd = emscripten.pollfd;
+pub const rlim_t = emscripten.rlim_t;
+pub const rlimit = emscripten.rlimit;
+pub const rlimit_resource = emscripten.rlimit_resource;
+pub const rusage = emscripten.rusage;
+pub const siginfo_t = emscripten.siginfo_t;
+pub const sigset_t = emscripten.sigset_t;
+pub const sockaddr = emscripten.sockaddr;
+pub const socklen_t = emscripten.socklen_t;
+pub const stack_t = emscripten.stack_t;
+pub const tcflag_t = emscripten.tcflag_t;
+pub const termios = emscripten.termios;
+pub const time_t = emscripten.time_t;
+pub const timespec = emscripten.timespec;
+pub const timeval = emscripten.timeval;
+pub const timezone = emscripten.timezone;
+pub const ucontext_t = emscripten.ucontext_t;
+pub const uid_t = emscripten.uid_t;
+pub const utsname = emscripten.utsname;
+
+pub const _errno = struct {
+    extern "c" fn __errno_location() *c_int;
+}.__errno_location;
+
+pub const Stat = emscripten.Stat;
+
+pub const AI = struct {
+    pub const PASSIVE = 0x01;
+    pub const CANONNAME = 0x02;
+    pub const NUMERICHOST = 0x04;
+    pub const V4MAPPED = 0x08;
+    pub const ALL = 0x10;
+    pub const ADDRCONFIG = 0x20;
+    pub const NUMERICSERV = 0x400;
+};
+
+pub const NI = struct {
+    pub const NUMERICHOST = 0x01;
+    pub const NUMERICSERV = 0x02;
+    pub const NOFQDN = 0x04;
+    pub const NAMEREQD = 0x08;
+    pub const DGRAM = 0x10;
+    pub const NUMERICSCOPE = 0x100;
+    pub const MAXHOST = 255;
+    pub const MAXSERV = 32;
+};
+
+pub const EAI = enum(c_int) {
+    BADFLAGS = -1,
+    NONAME = -2,
+    AGAIN = -3,
+    FAIL = -4,
+    FAMILY = -6,
+    SOCKTYPE = -7,
+    SERVICE = -8,
+    MEMORY = -10,
+    SYSTEM = -11,
+    OVERFLOW = -12,
+
+    NODATA = -5,
+    ADDRFAMILY = -9,
+    INPROGRESS = -100,
+    CANCELED = -101,
+    NOTCANCELED = -102,
+    ALLDONE = -103,
+    INTR = -104,
+    IDN_ENCODE = -105,
+
+    _,
+};
+
+pub const fopen64 = std.c.fopen;
+pub const fstat64 = std.c.fstat;
+pub const fstatat64 = std.c.fstatat;
+pub const ftruncate64 = std.c.ftruncate;
+pub const getrlimit64 = std.c.getrlimit;
+pub const lseek64 = std.c.lseek;
+pub const mmap64 = std.c.mmap;
+pub const open64 = std.c.open;
+pub const openat64 = std.c.openat;
+pub const pread64 = std.c.pread;
+pub const preadv64 = std.c.preadv;
+pub const pwrite64 = std.c.pwrite;
+pub const pwritev64 = std.c.pwritev;
+pub const setrlimit64 = std.c.setrlimit;
+
+pub extern "c" fn sigaltstack(ss: ?*stack_t, old_ss: ?*stack_t) c_int;
+pub extern "c" fn pipe2(fds: *[2]fd_t, flags: u32) c_int;
+pub extern "c" fn getentropy(buffer: [*]u8, size: usize) c_int;
+
+pub const pthread_attr_t = extern struct {
+    __size: [56]u8,
+    __align: c_long,
+};
+
 pub const pthread_mutex_t = extern struct {
     size: [__SIZEOF_PTHREAD_MUTEX_T]u8 align(4) = [_]u8{0} ** __SIZEOF_PTHREAD_MUTEX_T,
 };
@@ -7,5 +173,30 @@ pub const pthread_cond_t = extern struct {
 pub const pthread_rwlock_t = extern struct {
     size: [32]u8 align(4) = [_]u8{0} ** 32,
 };
+
 const __SIZEOF_PTHREAD_COND_T = 48;
-const __SIZEOF_PTHREAD_MUTEX_T = 28;
+const __SIZEOF_PTHREAD_MUTEX_T = 24;
+
+pub const pthread_key_t = c_uint;
+pub const sem_t = extern struct {
+    __size: [__SIZEOF_SEM_T]u8 align(@alignOf(usize)),
+};
+
+const __SIZEOF_SEM_T = 4 * @sizeOf(usize);
+
+pub const RTLD = struct {
+    pub const LAZY = 1;
+    pub const NOW = 2;
+    pub const NOLOAD = 4;
+    pub const NODELETE = 4096;
+    pub const GLOBAL = 256;
+    pub const LOCAL = 0;
+};
+
+pub const dirent = struct {
+    d_ino: c_uint,
+    d_off: c_uint,
+    d_reclen: c_ushort,
+    d_type: u8,
+    d_name: [256]u8,
+};

lib/std/os.zig

@@ -37,6 +37,7 @@ pub const linux = @import("os/linux.zig");
 pub const plan9 = @import("os/plan9.zig");
 pub const uefi = @import("os/uefi.zig");
 pub const wasi = @import("os/wasi.zig");
+pub const emscripten = @import("os/emscripten.zig");
 pub const windows = @import("os/windows.zig");
 
 comptime {
@@ -508,6 +509,13 @@ pub fn getrandom(buffer: []u8) GetRandomError!void {
         }
         return;
     }
+    if (builtin.os.tag == .emscripten) {
+        const err = std.c.getErrno(std.c.getentropy(buffer.ptr, buffer.len));
+        switch (err) {
+            .SUCCESS => return,
+            else => return unexpectedErrno(err),
+        }
+    }
     switch (builtin.os.tag) {
         .netbsd, .openbsd, .macos, .ios, .tvos, .watchos => {
             system.arc4random_buf(buffer.ptr, buffer.len);