sysv execve add zipos support. Add Linux zipos APE execve by leaking fd

libc/calls/execve-sysv.c

@@ -25,14 +25,18 @@
 #include "libc/errno.h"
 #include "libc/intrin/bits.h"
 #include "libc/intrin/safemacros.internal.h"
+#include "libc/intrin/weaken.h"
 #include "libc/mem/alloca.h"
 #include "libc/paths.h"
 #include "libc/runtime/runtime.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/at.h"
+#include "libc/sysv/consts/f.h"
+#include "libc/sysv/consts/fd.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/sysv/consts/ok.h"
 #include "libc/sysv/errfuns.h"
+#include "libc/zipos/zipos.internal.h"
 
 static bool CanExecute(const char *path) {
   return !sys_faccessat(AT_FDCWD, path, X_OK, 0);
@@ -71,16 +75,42 @@ static const char *Join(const char *a, const char *b, char buf[PATH_MAX]) {
 
 int sys_execve(const char *prog, char *const argv[], char *const envp[]) {
   size_t i;
-  int e, rc;
-  char *buf;
+  int e, rc, fd, flags;
+  char *buf, *newprog;
   char **shargs;
   const char *ape;
+  struct ZiposUri uri;
+  if (_weaken(__zipos_parseuri)(prog, &uri) != -1) {
+    if (IsLinux()) {
+      newprog = alloca(PATH_MAX);
+      fd = _weaken(__zipos_uri_to_mem_file)(&uri, newprog);
+      prog = newprog;
+    } else if (IsFreebsd()) {
+      if ((fd = _weaken(__zipos_uri_to_mem_file)(&uri, NULL)) != -1) {
+        return sys_fexecve(fd, argv, envp);
+      }
+    } else {
+      return enosys();
+    }
+    if (fd == -1) {
+      return -1;
+    }
+  } else {
+    fd = -1;
+  }
   e = errno;
   __sys_execve(prog, argv, envp);
   if (errno == ENOEXEC) {
     for (i = 0; argv[i];) ++i;
     buf = alloca(PATH_MAX);
     shargs = alloca((i + 4) * sizeof(char *));
+    if (fd != -1) {
+      flags = fcntl(fd, F_GETFD);
+      if (flags != -1) {
+        fcntl(fd, F_SETFD, flags & (~FD_CLOEXEC));
+        flags = fcntl(fd, F_GETFD);
+      }
+    }
     if (IsApeBinary(prog) &&
         (CanExecute((ape = "/usr/bin/ape")) ||
          CanExecute((ape = Join(firstnonnull(getenv("TMPDIR"),

test/libc/calls/execve_test.c

@@ -17,6 +17,8 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/dce.h"
+#include "libc/errno.h"
 #include "libc/fmt/conv.h"
 #include "libc/fmt/itoa.h"
 #include "libc/runtime/runtime.h"
@@ -58,3 +60,27 @@ TEST(execve, testArgPassing) {
     EXITS(0);
   }
 }
+
+TEST(execve, ziposELF) {
+  if (!IsLinux() && !IsFreebsd()) {
+    EXPECT_SYS(ENOSYS, -1,
+               execve("/zip/life.elf", (char *const[]){0}, (char *const[]){0}));
+    return;
+  }
+  SPAWN(fork);
+  execve("/zip/life.elf", (char *const[]){0}, (char *const[]){0});
+  notpossible;
+  EXITS(42);
+}
+
+TEST(execve, ziposAPE) {
+  if (!IsLinux()) {
+    EXPECT_EQ(-1, execve("/zip/life-nomod.com", (char *const[]){0},
+                         (char *const[]){0}));
+    return;
+  }
+  SPAWN(fork);
+  execve("/zip/life-nomod.com", (char *const[]){0}, (char *const[]){0});
+  notpossible;
+  EXITS(42);
+}