ncurses 6.4 - patch 20240323

[ncurses.git] / ncurses / tinfo / lib_setup.c

diff --git a/ncurses/tinfo/lib_setup.c b/ncurses/tinfo/lib_setup.c
index f50c1cf16176028e511dcaaec21557fa7b5247ef..e62aad794b557683de3bc08bb4318bcbdd78d0eb 100644 (file)
--- a/ncurses/tinfo/lib_setup.c
+++ b/ncurses/tinfo/lib_setup.c
@@ -49,7 +49,7 @@
 #include <locale.h>
 #endif
 
-MODULE_ID("$Id: lib_setup.c,v 1.232 2024/03/02 19:42:13 tom Exp $")
+MODULE_ID("$Id: lib_setup.c,v 1.233 2024/03/16 23:39:28 tom Exp $")
 
 /****************************************************************************
  *
@@ -332,7 +332,9 @@ get_position(TERMINAL *termp, int fd, int *row, int *col)
        int y, x;
        char buf[20];
        char *s;
-       char ignore;
+       char cc;
+       const char *skipped;
+       int scanned;
 
        s = memset(buf, '\0', sizeof(buf));
        do {
@@ -343,15 +345,19 @@ get_position(TERMINAL *termp, int fd, int *row, int *col)
            s += got;
            *s = '\0';
        } while (strchr(buf, 'R') == NULL && (size_t) (s + 1 - buf) < sizeof(buf));
-       T(("response %s", _nc_visbuf(buf)));
-       if (sscanf(skip_csi(buf), "%d;%d%c", &y, &x, &ignore) != 2
-           || (ignore != 'R' && ignore != ';')) {
+       T(("CPR response %s", _nc_visbuf(buf)));
+       skipped = skip_csi(buf);
+       cc = '\0';
+       if (skipped != buf
+           && *skipped != '\0'
+           && (scanned = sscanf(skip_csi(buf), "%d;%d%c", &y, &x, &cc)) == 3
+           && (cc == 'R')) {
            *row = y;
            *col = x;
            result = TRUE;
        }
     }
-    T(("get_position %d,%d", *row, *col));
+    T(("get_position %s %d,%d", result ? "OK" : "ERR", *row, *col));
     return result;
 }
 
@@ -371,23 +377,40 @@ set_position(TERMINAL *termp, int fd, int row, int col)
 
 /*
  * This is a little more complicated than one might expect, because we do this
- * before setting up the terminal modes, etc.
+ * before setting up the terminal modes, etc., and cannot use the timeout or
+ * buffering functions.
+ *
+ * We check if the terminal description has the ECMA-48 CPR (cursor position
+ * report) in u7 and the response in u6.  The two variations of is_expected()
+ * cover the termcap style and terminfo style, and are equivalent as far as we
+ * are concerned.  For analyzing the response, we wait (a short time) for 'R'
+ * to be echoed, and then check if we received two integers in the response.
+ *
+ * In principle, this could run on "any" ECMA-48 terminal, but in practice,
+ * there is a scenario using GNU screen where it uses ncurses with a partially
+ * configured pseudo-terminal, and the CPR response goes to the wrong place.
+ * So we do a simple check to exclude pseudo-terminals.
  */
 static void
 _nc_check_screensize(TERMINAL *termp, int *linep, int *colp)
 {
-    int fd = fileno(stderr);
+    int fd = termp->Filedes;
     TTY saved;
+    const char *name;
 
     if (NC_ISATTY(fd)
+       && (name = ttyname(fd)) != NULL
+       && strncmp(name, "/dev/pts/", 9)
        && VALID_STRING(cursor_address)
        && is_expected(user7, "6n")
-       && is_expected(user6, "%i%d;%dR")
+       && (is_expected(user6, "%i%d;%dR") ||
+           is_expected(user6, "%i%p1%d;%p2%dR"))
        && GET_TTY(fd, &saved) == OK) {
        int current_y = -1, current_x = -1;
        int updated_y = -1, updated_x = -1;
        TTY alter = saved;
 
+       T(("checking screensize of %s", name));
        alter.c_lflag &= (unsigned) ~(ECHO | ICANON | ISIG | IEXTEN);
        alter.c_iflag &= (unsigned) ~(IXON | BRKINT | PARMRK);
        alter.c_cc[VMIN] = 0;
@@ -445,6 +468,7 @@ _nc_get_screensize(SCREEN *sp,
     bool useEnv = _nc_prescreen.use_env;
     bool useTioctl = _nc_prescreen.use_tioctl;
 
+    T((T_CALLED("_nc_get_screensize (%p)"), sp));
 #ifdef EXP_WIN32_DRIVER
     /* If we are here, then Windows console is used in terminfo mode.
        We need to figure out the size using the console API
@@ -466,6 +490,7 @@ _nc_get_screensize(SCREEN *sp,
     }
 #endif
 
+    T(("useEnv:%d useTioctl:%d", useEnv, useTioctl));
     if (useEnv || useTioctl) {
 #ifdef __EMX__
        {
@@ -565,6 +590,7 @@ _nc_get_screensize(SCREEN *sp,
     TABSIZE = my_tabsize;
 #endif
     T(("TABSIZE = %d", TABSIZE));
+    returnVoid;
 #endif /* USE_TERM_DRIVER */
 }