Re-enable/fix non-argv[0] exe name tests (#1046)

Author: mrdomino

test/libc/calls/getprogramexecutablename_test.c

@@ -17,28 +17,55 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/metalfile.internal.h"
 #include "libc/dce.h"
 #include "libc/limits.h"
 #include "libc/runtime/runtime.h"
+#include "libc/serialize.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/o.h"
+#include "libc/sysv/consts/ok.h"
 #include "libc/testlib/ezbench.h"
 #include "libc/testlib/subprocess.h"
 #include "libc/testlib/testlib.h"
 
 static char *self;
+static bool skiptests;
 
 void SetUpOnce(void) {
   self = GetProgramExecutableName();
   testlib_enable_tmp_setup_teardown();
+  if (IsMetal()) {
+    skiptests = true;
+  } else if (IsOpenbsd() || (IsXnu() && !IsXnuSilicon())) {
+    ASSERT_STRNE(self, "");
+    ASSERT_SYS(0, 3, open(self, O_RDONLY));
+    char buf[8];
+    ASSERT_SYS(0, 8, pread(3, buf, 8, 0));
+    ASSERT_SYS(0, 0, close(3));
+    if (READ64LE(buf) != READ64LE("MZqFpD='") &&
+        READ64LE(buf) != READ64LE("jartsr='") &&
+        READ64LE(buf) != READ64LE("APEDBG='")) {
+      fprintf(stderr,
+              "we appear to be running as an assimilated binary on OpenBSD or "
+              "x86_64 XNU;\nGetProgramExecutableName is unreliable here\n");
+      skiptests = true;
+    }
+  }
 }
 
 __attribute__((__constructor__)) static void Child(int argc, char *argv[]) {
   if (argc >= 2 && !strcmp(argv[1], "Child")) {
     if (strcmp(argv[2], GetProgramExecutableName())) {
       exit(123);
     }
+    if (!IsXnuSilicon()) exit(0);
+    /* TODO(mrdomino): argv[0] tests only pass on XnuSilicon right now because
+                       __sys_execve fails there, so the ape loader is used.
+                       the correct check is "we have been invoked either as an
+                       assimilated binary or via the ape loader, and not via a
+                       raw __sys_execve." */
     if (strcmp(argv[3], argv[0])) {
       exit(124);
     }
@@ -47,34 +74,33 @@ __attribute__((__constructor__)) static void Child(int argc, char *argv[]) {
 }
 
 TEST(GetProgramExecutableName, ofThisFile) {
-  EXPECT_EQ('/', *self);
-  EXPECT_TRUE(!!strstr(self, "getprogramexecutablename_test"));
+  if (IsMetal()) {
+    EXPECT_STREQ(self, APE_COM_NAME);
+  } else {
+    EXPECT_EQ('/', *self);
+    EXPECT_TRUE(!!strstr(self, "getprogramexecutablename_test"));
+    EXPECT_SYS(0, 0, access(self, X_OK));
+  }
 }
 
-/* TODO(mrdomino): these tests only pass on XnuSilicon right now because
-                   __sys_execve fails there, so the ape loader is used.
-                   the correct check here is "we have been invoked either
-                   as an assimilated binary or via the ape loader, and not
-                   via a raw __sys_execve." */
-
 TEST(GetProgramExecutableName, nullEnv) {
-  if (!IsXnuSilicon()) return;
+  if (skiptests) return;
   SPAWN(fork);
   execve(self, (char *[]){self, "Child", self, self, 0}, (char *[]){0});
   abort();
   EXITS(0);
 }
 
 TEST(GetProramExecutableName, weirdArgv0NullEnv) {
-  if (!IsXnuSilicon()) return;
+  if (skiptests) return;
   SPAWN(fork);
   execve(self, (char *[]){"hello", "Child", self, "hello", 0}, (char *[]){0});
   abort();
   EXITS(0);
 }
 
 TEST(GetProgramExecutableName, weirdArgv0CosmoVar) {
-  if (!IsXnuSilicon()) return;
+  if (skiptests) return;
   char buf[32 + PATH_MAX];
   stpcpy(stpcpy(buf, "COSMOPOLITAN_PROGRAM_EXECUTABLE="), self);
   SPAWN(fork);
@@ -85,7 +111,7 @@ TEST(GetProgramExecutableName, weirdArgv0CosmoVar) {
 }
 
 TEST(GetProgramExecutableName, weirdArgv0WrongCosmoVar) {
-  if (!IsXnuSilicon()) return;
+  if (skiptests) return;
   char *bad = "COSMOPOLITAN_PROGRAM_EXECUTABLE=hi";
   SPAWN(fork);
   execve(self, (char *[]){"hello", "Child", self, "hello", 0},
@@ -95,7 +121,7 @@ TEST(GetProgramExecutableName, weirdArgv0WrongCosmoVar) {
 }
 
 TEST(GetProgramExecutableName, movedSelf) {
-  if (!IsXnuSilicon()) return;
+  if (skiptests) return;
   char buf[BUFSIZ];
   ASSERT_SYS(0, 3, open(GetProgramExecutableName(), O_RDONLY));
   ASSERT_SYS(0, 4, creat("test", 0755));