Fix warnings

This change fixes Cosmopolitan so it has fewer opinions about compiler
warnings. The whole repository had to be cleaned up to be buildable in
-Werror -Wall mode. This lets us benefit from things like strict const
checking. Some actual bugs might have been caught too.

libc/sock/accept-nt.c

@@ -46,7 +46,7 @@ struct AcceptExBuffer {
 textwindows int sys_accept_nt(struct Fd *fd, struct sockaddr_storage *addr,
                               int accept4_flags) {
   int64_t handle;
-  int rc, client, oflags;
+  int client, oflags;
   uint32_t bytes_received;
   uint32_t completion_flags;
   struct AcceptExBuffer buffer;

libc/sock/inet_ntop.c

@@ -32,8 +32,8 @@
  */
 const char *inet_ntop(int af, const void *src, char *dst, uint32_t size) {
   char *p;
-  unsigned char *ip;
   int i, t, a, b, c, d;
+  const unsigned char *ip;
   p = dst;
   if (!size) return dst;
   if ((ip = src)) {

libc/sock/inet_pton.c

@@ -46,7 +46,7 @@ static int inet_pton_inet6_impl(const char *src, uint8_t *dst) {
   unsigned digitsLeft = 32;
   bool zeroFound = false;
   uint16_t currentSet = 0;
-  while (c = *src++) {
+  while ((c = *src++)) {
     if (digitsLeft == 0) {
       return 0;
     }

libc/sock/kntwsadata.c

@@ -37,7 +37,7 @@
 struct NtWsaData kNtWsaData;
 
 static textwindows void WinSockCleanup(void) {
-  int i, rc;
+  int rc;
   (void)rc;
   rc = WSACleanup();
   NTTRACE("WSACleanup() → %d% lm", rc);

libc/sock/nointernet.c

@@ -284,7 +284,6 @@ static int WaitForTrace(int main) {
 int nointernet(void) {
   int ws, act, main;
   sigset_t set, old;
-  char path[PATH_MAX];
   struct sock_fprog prog = {.filter = kInetBpf, .len = ARRAYLEN(kInetBpf)};
 
   // seccomp bpf and ptrace are pretty much just linux for now.

libc/sock/pselect.c

@@ -60,7 +60,6 @@
 int pselect(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
             const struct timespec *timeout, const sigset_t *sigmask) {
   int rc;
-  sigset_t oldmask;
   struct timeval tv, *tvp;
   struct timespec ts, *tsp;
   struct {
@@ -89,7 +88,8 @@ int pselect(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
     ss.n = 8;
     rc = sys_pselect(nfds, readfds, writefds, exceptfds, tsp, &ss);
   } else if (!IsWindows()) {
-    rc = sys_pselect(nfds, readfds, writefds, exceptfds, timeout, sigmask);
+    rc = sys_pselect(nfds, readfds, writefds, exceptfds,
+                     (struct timespec *)timeout, sigmask);
   } else {
     if (timeout) {
       tv.tv_sec = timeout->tv_sec;

libc/sock/recv.c

@@ -42,7 +42,7 @@
  * @restartable (unless SO_RCVTIMEO)
  */
 ssize_t recv(int fd, void *buf, size_t size, int flags) {
-  ssize_t rc, got;
+  ssize_t rc;
   BEGIN_CANCELLATION_POINT;
 
   if (IsAsan() && !__asan_is_valid(buf, size)) {

libc/sock/send.c

@@ -54,12 +54,12 @@ ssize_t send(int fd, const void *buf, size_t size, int flags) {
     rc = sys_sendto(fd, buf, size, flags, 0, 0);
   } else if (__isfdopen(fd)) {
     if (__isfdkind(fd, kFdSocket)) {
-      rc = sys_send_nt(fd, (struct iovec[]){{buf, size}}, 1, flags);
+      rc = sys_send_nt(fd, (struct iovec[]){{(void *)buf, size}}, 1, flags);
     } else if (__isfdkind(fd, kFdFile)) {
       if (flags) {
         rc = einval();
       } else {
-        rc = sys_write_nt(fd, (struct iovec[]){{buf, size}}, 1, -1);
+        rc = sys_write_nt(fd, (struct iovec[]){{(void *)buf, size}}, 1, -1);
       }
     } else {
       rc = enotsock();

libc/sock/sendfile.c

@@ -43,7 +43,6 @@
 // sendfile() isn't specified as raising eintr
 static textwindows int SendfileBlock(int64_t handle,
                                      struct NtOverlapped *overlapped) {
-  int rc;
   uint32_t i, got, flags = 0;
   if (WSAGetLastError() != kNtErrorIoPending &&
       WSAGetLastError() != WSAEINPROGRESS) {

libc/sock/sendto.c

@@ -74,15 +74,15 @@ ssize_t sendto(int fd, const void *buf, size_t size, int flags,
     }
   } else if (__isfdopen(fd)) {
     if (__isfdkind(fd, kFdSocket)) {
-      rc = sys_sendto_nt(fd, (struct iovec[]){{buf, size}}, 1, flags, opt_addr,
-                         addrsize);
+      rc = sys_sendto_nt(fd, (struct iovec[]){{(void *)buf, size}}, 1, flags,
+                         opt_addr, addrsize);
     } else if (__isfdkind(fd, kFdFile)) {
       if (flags) {
         rc = einval();
       } else if (opt_addr) {
         rc = eisconn();
       } else {
-        rc = sys_write_nt(fd, (struct iovec[]){{buf, size}}, 1, -1);
+        rc = sys_write_nt(fd, (struct iovec[]){{(void *)buf, size}}, 1, -1);
       }
     } else {
       rc = enotsock();

libc/sock/setsockopt-nt.c

@@ -34,9 +34,9 @@ __msabi extern typeof(__sys_setsockopt_nt) *const __imp_setsockopt;
 textwindows int sys_setsockopt_nt(struct Fd *fd, int level, int optname,
                                   const void *optval, uint32_t optlen) {
   int64_t ms, micros;
-  struct timeval *tv;
-  struct linger *linger;
   struct SockFd *sockfd;
+  const struct timeval *tv;
+  const struct linger *linger;
   union {
     uint32_t millis;
     struct linger_nt linger;

libc/sock/sockdebug.c

@@ -32,7 +32,6 @@ const char *(DescribeSockaddr)(char buf[128], const struct sockaddr *sa,
                                size_t sasize) {
   int e;
   size_t n;
-  uint16_t port;
   char *p, ip[72];
   e = errno;
   stpcpy(buf, "NULL");

libc/sock/socketpair-nt.c

@@ -33,8 +33,8 @@
 
 textwindows int sys_socketpair_nt(int family, int type, int proto, int sv[2]) {
   uint32_t mode;
+  int64_t hpipe, h1;
   char16_t pipename[64];
-  int64_t hpipe, h1, h2;
   int rc, reader, writer, oflags;
 
   // Supports only AF_UNIX

libc/sock/syslog.c

@@ -19,7 +19,6 @@
 #include "libc/sock/syslog.h"
 #include "libc/calls/blockcancel.internal.h"
 #include "libc/calls/calls.h"
-#include "libc/stdio/dprintf.h"
 #include "libc/calls/struct/timespec.h"
 #include "libc/calls/weirdtypes.h"
 #include "libc/dce.h"
@@ -32,6 +31,7 @@
 #include "libc/nt/runtime.h"
 #include "libc/sock/sock.h"
 #include "libc/sock/struct/sockaddr.h"
+#include "libc/stdio/dprintf.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/af.h"
@@ -261,7 +261,6 @@ int setlogmask(int maskpri) {
  * @asyncsignalsafe
  */
 void openlog(const char *ident, int opt, int facility) {
-  size_t n;
   BLOCK_CANCELLATIONS;
   if (log_facility == -1) __initlog();
   if (!ident) ident = firstnonnull(program_invocation_short_name, "unknown");

libc/sock/wsablock.c

@@ -43,8 +43,8 @@ static textwindows void __wsablock_abort(int64_t handle,
 
 textwindows int __wsablock(struct Fd *fd, struct NtOverlapped *overlapped,
                            uint32_t *flags, int sigops, uint32_t timeout) {
+  int abort_errno;
   uint32_t i, got;
-  int rc, abort_errno;
   if (WSAGetLastError() != kNtErrorIoPending) {
     // our i/o operation never happened because it failed
     return __winsockerr();