Make improvements

- Improved async signal safety of read() particularly for longjmp()
- Started adding cancel cleanup handlers for locks / etc on Windows
- Make /dev/tty work better particularly for uses like `foo | less`
- Eagerly read console input into a linked list, so poll can signal
- Fix some libc definitional bugs, which configure scripts detected

test/libc/calls/read_test.c

@@ -17,6 +17,7 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/assert.h"
+#include "libc/atomic.h"
 #include "libc/calls/calls.h"
 #include "libc/calls/cp.internal.h"
 #include "libc/calls/internal.h"
@@ -26,12 +27,14 @@
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/dce.h"
 #include "libc/errno.h"
+#include "libc/runtime/runtime.h"
 #include "libc/sock/internal.h"
 #include "libc/sysv/consts/nr.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/testlib/ezbench.h"
 #include "libc/testlib/testlib.h"
+#include "libc/thread/thread.h"
 
 void SetUpOnce(void) {
   testlib_enable_tmp_setup_teardown();
@@ -82,6 +85,57 @@ TEST(read_directory, eisdir) {
   ASSERT_SYS(0, 0, close(3));
 }
 
+int fds[2];
+jmp_buf jb;
+pthread_t th;
+atomic_bool isdone;
+
+void *GenerateSignals(void *arg) {
+  while (!isdone) {
+    usleep(123);
+    pthread_kill(th, SIGINT);
+  }
+  return 0;
+}
+
+void *GenerateData(void *arg) {
+  for (;;) {
+    usleep(223);
+    int rc = write(fds[1], "hi", 2);
+    if (rc == -1 && errno == EPIPE) break;
+    ASSERT_EQ(2, rc);
+  }
+  return 0;
+}
+
+void OnSig(int sig) {
+  char buf[8];
+  ASSERT_SYS(0, 2, read(fds[0], buf, 8));
+  longjmp(jb, 1);
+}
+
+TEST(read, whatEmacsDoes) {
+  pthread_t sigth;
+  sighandler_t sh1 = signal(SIGINT, SIG_IGN);
+  sighandler_t sh2 = signal(SIGPIPE, SIG_IGN);
+  ASSERT_SYS(0, 0, pipe(fds));
+  ASSERT_EQ(0, pthread_create(&th, 0, GenerateData, 0));
+  ASSERT_EQ(0, pthread_create(&sigth, 0, GenerateSignals, 0));
+  for (int i = 0; i < 100; ++i) {
+    if (!setjmp(jb)) {
+      char buf[8];
+      ASSERT_GE(read(fds[0], buf, 8), 2);
+    }
+  }
+  isdone = true;
+  ASSERT_SYS(0, 0, close(fds[0]));
+  ASSERT_EQ(0, pthread_join(sigth, 0));
+  ASSERT_EQ(0, pthread_join(th, 0));
+  ASSERT_SYS(0, 0, close(fds[1]));
+  signal(SIGPIPE, sh2);
+  signal(SIGINT, sh1);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 
 BENCH(read, bench) {

test/libc/runtime/getdosargv_test.c

@@ -25,11 +25,6 @@
 #include "libc/testlib/testlib.h"
 
 void SetUpOnce(void) {
-  if (!IsWindows()) {
-    // TODO(jart): mock out that win32 i/o call
-    tinyprint(2, program_invocation_name, ": skipping on non-windows\n", NULL);
-    exit(0);
-  }
   testlib_enable_tmp_setup_teardown();
 }
 
@@ -197,16 +192,3 @@ TEST(GetDosArgv, cmdToil) {
   free(argv);
   free(buf);
 }
-
-TEST(GetDosArgv, canonicalizesCurrentDirectoryCommandPath) {
-  size_t max = 4;
-  size_t size = ARG_MAX / 2;
-  char *buf = malloc(size * sizeof(char));
-  char **argv = malloc(max * sizeof(char *));
-  ASSERT_SYS(0, 0, touch("emacs.com", 0755));
-  EXPECT_EQ(1, GetDosArgv(u"emacs.com", buf, size, argv, max));
-  EXPECT_STREQ(".\\emacs.com", argv[0]);
-  EXPECT_EQ(NULL, argv[1]);
-  free(argv);
-  free(buf);
-}

test/libc/thread/pthread_cancel_test.c

@@ -32,6 +32,7 @@
 #include "libc/thread/thread2.h"
 
 int pfds[2];
+atomic_bool ready;
 pthread_cond_t cv;
 pthread_mutex_t mu;
 atomic_int gotcleanup;
@@ -72,6 +73,7 @@ TEST(pthread_cancel, self_deferred_waitsForCancellationPoint) {
 
 void *Worker(void *arg) {
   char buf[8];
+  ready = true;
   pthread_cleanup_push(OnCleanup, 0);
   read(pfds[0], buf, sizeof(buf));
   pthread_cleanup_pop(0);
@@ -91,11 +93,12 @@ TEST(pthread_cancel, synchronous) {
   ASSERT_SYS(0, 0, close(pfds[0]));
 }
 
-TEST(pthread_cancel, synchronous_delayed) {
+TEST(pthread_cancel, synchronous_deferred) {
   void *rc;
   pthread_t th;
   ASSERT_SYS(0, 0, pipe(pfds));
   ASSERT_EQ(0, pthread_create(&th, 0, Worker, 0));
+  while (!ready) pthread_yield();
   ASSERT_SYS(0, 0, usleep(10));
   EXPECT_EQ(0, pthread_cancel(th));
   EXPECT_EQ(0, pthread_join(th, &rc));