Make improvements

- Expand redbean UNIX module
- Expand redbean documentation
- Ensure Lua copyright is embedded in binary
- Increase the PATH_MAX limit especially on NT
- Use column major sorting for linenoise completions
- Fix some suboptimalities in redbean's new UNIX API
- Figured out right flags for Multics newline in raw mode

libc/runtime/mprotect.greg.c

@@ -16,26 +16,16 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/bits/asmflag.h"
 #include "libc/bits/likely.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/strace.internal.h"
 #include "libc/dce.h"
-#include "libc/errno.h"
 #include "libc/intrin/describeflags.internal.h"
-#include "libc/macros.internal.h"
-#include "libc/nt/memory.h"
-#include "libc/nt/thunk/msabi.h"
-#include "libc/runtime/directmap.internal.h"
-#include "libc/runtime/memtrack.internal.h"
-#include "libc/sysv/consts/nr.h"
+#include "libc/runtime/internal.h"
+#include "libc/runtime/runtime.h"
 #include "libc/sysv/consts/prot.h"
 #include "libc/sysv/errfuns.h"
 
-__msabi extern typeof(VirtualProtect) *const __imp_VirtualProtect;
-
-#define ADDR(x) ((char *)((int64_t)((uint64_t)(x) << 32) >> 16))
-
 /**
  * Modifies restrictions on virtual memory address range.
  *
@@ -44,12 +34,8 @@ __msabi extern typeof(VirtualProtect) *const __imp_VirtualProtect;
  * @return 0 on success, or -1 w/ errno
  * @see mmap()
  */
-noasan noubsan privileged int mprotect(void *addr, size_t size, int prot) {
-  bool cf;
+privileged int mprotect(void *addr, size_t size, int prot) {
   int64_t rc;
-  unsigned i;
-  uint32_t op;
-  char *a, *b, *x, *y, *p;
   if (SupportsWindows() && (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC |
                                      PROT_GROWSDOWN | PROT_GROWSUP))) {
     rc = einval();  // unix checks prot before checking size
@@ -58,48 +44,9 @@ noasan noubsan privileged int mprotect(void *addr, size_t size, int prot) {
   } else if (UNLIKELY((intptr_t)addr & 4095)) {
     rc = einval();
   } else if (!IsWindows()) {
-    asm volatile(CFLAG_ASM("clc\n\tsyscall")
-                 : CFLAG_CONSTRAINT(cf), "=a"(rc)
-                 : "1"(__NR_mprotect), "D"(addr), "S"(size), "d"(prot)
-                 : "rcx", "r11", "memory", "cc");
-    if (cf) {
-      errno = rc;
-      rc = -1;
-    } else if (rc > -4096ul) {
-      errno = -rc;
-      rc = -1;
-    }
+    rc = sys_mprotect(addr, size, prot);
   } else {
-    rc = 0;
-    p = addr;
-    i = FindMemoryInterval(&_mmi, (intptr_t)p >> 16);
-    if (i == _mmi.i || (!i && p + size <= ADDR(_mmi.p[0].x))) {
-      // memory isn't in memtrack
-      // let's just trust the user then
-      // it's probably part of the executable
-      if (!VirtualProtect(addr, size, __prot2nt(prot, false), &op)) {
-        rc = -1;
-      }
-    } else {
-      // memory is in memtrack, so use memtrack, to do dimensioning
-      // we unfortunately must do something similar to this for cow
-      for (; i < _mmi.i; ++i) {
-        x = ADDR(_mmi.p[i].x);
-        y = x + _mmi.p[i].size;
-        if ((x <= p && p < y) || (x < p + size && p + size <= y) ||
-            (p < x && y < p + size)) {
-          a = MIN(MAX(p, x), y);
-          b = MAX(MIN(p + size, y), x);
-          if (!VirtualProtect(a, b - a, __prot2nt(prot, _mmi.p[i].iscow),
-                              &op)) {
-            rc = -1;
-            break;
-          }
-        } else {
-          break;
-        }
-      }
-    }
+    rc = sys_mprotect_nt(addr, size, prot);
   }
   STRACE("mprotect(%p, %'zu, %s) → %d% m", addr, size, DescribeProtFlags(prot),
          rc);