RLIMIT_NOFILE >= 4096 when on TCL9 support

graphics/grMain.c

@@ -457,8 +457,15 @@ grFgets(str, n, stream, name)
     twentySecs.tv_sec = 20;
     twentySecs.tv_usec = 0;
 
+    const int fd = fileno(stream);
+    ASSERT(fd >= 0 && fd < FD_SETSIZE, "fd>=0&&fd<FD_SETSIZE");
+    if (fd < 0 || fd >= FD_SETSIZE)
+    {
+	TxError("WARNING: grFgets(fd=%d) called with fd out of range 0..%d\n", fd, FD_SETSIZE-1);
+	return NULL; /* allowing things to continue is UB */
+    }
     FD_ZERO(&fn);
-    FD_SET(fileno(stream), &fn);
+    FD_SET(fd, &fn);
     newstr = str;
     n--;
     if (n < 0) return (char *) NULL;
@@ -470,13 +477,13 @@ grFgets(str, n, stream, name)
         int sel;
 
 	f = fn;
-	sel = select(TX_MAX_OPEN_FILES, &f, (fd_set *) NULL, (fd_set *) NULL, &threeSec);
+	sel = select(fd + 1, &f, (fd_set *) NULL, (fd_set *) NULL, &threeSec);
 	if  (sel == 0)
 	{
 	    TxError("The %s is responding slowly, or not at all.\n", name);
 	    TxError("I'll wait for 20 seconds and then give up.\n");
 	    f = fn;
-	    sel = select(TX_MAX_OPEN_FILES, &f, (fd_set *) NULL,
+	    sel = select(fd + 1, &f, (fd_set *) NULL,
 			(fd_set *) NULL, &twentySecs);
 	    if (sel == 0)
 	    {

scripts/configure

@@ -4893,6 +4893,30 @@ fi
 done
 
 
+for ac_func in getrlimit
+do :
+  ac_fn_c_check_func "$LINENO" "getrlimit" "ac_cv_func_getrlimit"
+if test "x$ac_cv_func_getrlimit" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_GETRLIMIT 1
+_ACEOF
+
+fi
+done
+
+
+for ac_func in setrlimit
+do :
+  ac_fn_c_check_func "$LINENO" "setrlimit" "ac_cv_func_setrlimit"
+if test "x$ac_cv_func_setrlimit" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_SETRLIMIT 1
+_ACEOF
+
+fi
+done
+
+
 ac_fn_c_check_func "$LINENO" "vfork" "ac_cv_func_vfork"
 if test "x$ac_cv_func_vfork" = xyes; then :
 
@@ -4964,6 +4988,19 @@ fi
 done
 
 
+for ac_header in sys/resource.h
+do :
+  ac_fn_c_check_header_mongrel "$LINENO" "sys/resource.h" "ac_cv_header_sys_resource_h" "$ac_includes_default"
+if test "x$ac_cv_header_sys_resource_h" = xyes; then :
+  cat >>confdefs.h <<_ACEOF
+#define HAVE_SYS_RESOURCE_H 1
+_ACEOF
+
+fi
+
+done
+
+
 for ac_header in sys/time.h
 do :
   ac_fn_c_check_header_mongrel "$LINENO" "sys/time.h" "ac_cv_header_sys_time_h" "$ac_includes_default"

scripts/configure.in

@@ -132,6 +132,12 @@ AC_HEADER_STDC
 dnl Need either setenv or putenv
 AC_CHECK_FUNCS(setenv putenv)
 
+dnl Check for getrlimit
+AC_CHECK_FUNCS(getrlimit)
+
+dnl Check for setrlimit
+AC_CHECK_FUNCS(setrlimit)
+
 dnl Check for vfork
 AC_CHECK_FUNC(vfork)
 
@@ -150,6 +156,9 @@ AC_CHECK_HEADERS(param.h)
 dnl Check for <paths.h>
 AC_CHECK_HEADERS(paths.h)
 
+dnl Check for <sys/resource.h>
+AC_CHECK_HEADERS(sys/resource.h)
+
 dnl Check for <sys/time.h>
 AC_CHECK_HEADERS(sys/time.h)
 

sim/SimRsim.c

@@ -650,6 +650,13 @@ SimFillBuffer(buffHead, pLastChar, charCount)
     FD_ZERO(&exceptfds);
 #endif  /* SYSV */
 
+    ASSERT(pipeIn >= 0 && pipeIn < FD_SETSIZE, "pipeIn>=0&&pipeIn<FD_SETSIZE");
+    if (pipeIn < 0 || pipeIn >= FD_SETSIZE)
+    {
+        TxError("WARNING: SimFillBuffer(fd=%d) called with fd out of range 0..%d\n", pipeIn, FD_SETSIZE-1);
+        return -1; /* allowing things to continue is UB */
+    }
+
     nfd = pipeIn + 1;
 
 try_again:

tcltk/tclmagic.c

@@ -25,6 +25,9 @@
 #include <signal.h>
 #include <string.h>
 #include <errno.h>
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
 
 #include "tcltk/tclmagic.h"
 #include "utils/main.h"
@@ -530,6 +533,61 @@ MakeWindowCommand(char *wname, MagWindow *mw)
     freeMagic(tclcmdstr);
 }
 
+#ifdef HAVE_SETRLIMIT
+static int
+process_rlimit_nofile_ensure(rlim_t nofile)
+{
+    struct rlimit rlim;
+    int err = getrlimit(RLIMIT_NOFILE, &rlim);
+    if (err < 0)
+	return err;
+    rlim_t rlim_cur = rlim.rlim_cur;
+    /* nofile != RLIM_INFINITY && rlim.rlim_max != RLIM_INFINITY */
+    if (nofile > rlim.rlim_max && nofile != rlim.rlim_max)
+	return -1;
+    if (rlim.rlim_cur < nofile || nofile == RLIM_INFINITY)
+    {
+	rlim.rlim_cur = nofile;
+	err = setrlimit(RLIMIT_NOFILE, &rlim);
+    }
+    if (err != 0)
+	TxPrintf("WARNING: process_rlimit_nofile_ensure(%lu) = %d (%d) [rlim_cur=%lu rlim_max=%lu]\n", nofile, err, errno, rlim_cur, rlim.rlim_max);
+    return err;
+}
+#endif /* HAVE_SETRLIMIT */
+
+/* this function encapsulates the default policy on startup */
+static int
+process_rlimit_startup_check(void)
+{
+#ifdef HAVE_GETRLIMIT
+ #if TCL_MAJOR_VERSION < 9
+    /* TCL8 has select() support and no support for poll/epoll for the main event loop */
+    struct rlimit rlim;
+    int err = getrlimit(RLIMIT_NOFILE, &rlim);
+    if (err < 0)
+	return err;
+    if (rlim.rlim_cur > FD_SETSIZE)
+    {
+	TxPrintf("WARNING: RLIMIT_NOFILE is above %d and Tcl_Version<9 this may cause runtime issues [rlim_cur=%lu]\n", FD_SETSIZE, rlim.rlim_cur);
+	return -1;
+    }
+    return 0;
+ #else
+  #ifdef HAVE_SETRLIMIT
+    /* TCL9 has poll/epoll support for the main event loop,
+     * ifdef due to rlim_t type availbility
+     */
+    return process_rlimit_nofile_ensure(4096);
+  #else
+    return -1;
+  #endif /* HAVE_SETRLIMIT */
+ #endif /* TCL_MAJOR_VERSION < 9 */
+#else
+    return -1;
+#endif /* HAVE_GETRLIMIT */
+}
+
 /*------------------------------------------------------*/
 /* Main startup procedure				*/
 /*------------------------------------------------------*/
@@ -588,6 +646,8 @@ _magic_initialize(ClientData clientData,
 	TxPrintf("Using the terminal as the console.\n");
     TxFlushOut();
 
+    process_rlimit_startup_check();
+
     if (mainInitAfterArgs() != 0) goto magicfatal;
 
     /* Registration of commands is performed after calling the	*/

textio/textio.h

@@ -110,6 +110,4 @@ extern void TxInit(void);
 extern void TxInitReadline(void);
 #endif
 
-#define   TX_MAX_OPEN_FILES       20
-
 #endif /* _TEXTIO_H */