missing use_terminfo_vars() calls in ncurses-5.1-20001007

[Todd C. Miller]

This adds a few missing use_terminfo_vars() and fixes up _nc_tgetent().
Previously, _nc_cgetset() would still get called on cp so the
simplest thing is to set cp to NULL if !use_terminfo_vars().
This also makes the code a bit easier to read (IMO).  Additionally,
I added checks for a NUL HOME environment variable out of sheer,
raging paranoia.

Personally, I don't like reading .termcap from the cwd since it
could be hostile as well but I have not changed that here.  The
same does not seem to be true of the .terminfo dir.

 - todd

--- read_termcap.c.DIST Sat Oct  7 21:17:34 2000
+++ read_termcap.c      Sun Oct  8 16:35:35 2000
@@ -783,7 +783,7 @@
     pvec = pathvec;
     tbuf = bp;
     p = pathbuf;
-    cp = getenv("TERMCAP");
+    cp = use_terminfo_vars() ? getenv("TERMCAP") : NULL;
 
     /*
      * TERMCAP can have one of two things in it.  It can be the name of a file
@@ -795,23 +795,22 @@
      * "$HOME/.termcap /etc/termcap" if no TERMPATH exists.
      */
     _nc_str_init(&desc, pathbuf, sizeof(pathbuf));
-    if (!is_pathname(cp)) {    /* no TERMCAP or it holds an entry */
-       if (use_terminfo_vars()
-        && (termpath = getenv("TERMPATH")) != 0) {
+    if (cp == NULL) {
+       _nc_safe_strcpy(&desc, "/etc/termcap /usr/share/misc/termcap");
+    } else if (!is_pathname(cp)) {     /* TERMCAP holds an entry */
+       if ((termpath = getenv("TERMPATH")) != 0) {
            _nc_safe_strcat(&desc, termpath);
        } else {
-           if (use_terminfo_vars()) {
-               char temp[PBUFSIZ];
-               temp[0] = 0;
-               if ((home = getenv("HOME")) != 0
-                && strchr(home, ' ') == 0
-                && strlen(home) < sizeof(temp) - 10) { /* setup path */
-                   sprintf(temp, "%s/", home); /* $HOME first */
-               }
-               /* if no $HOME look in current directory */
-               strcat(temp, ".termcap");
-               _nc_safe_strcat(&desc, temp);
+           char temp[PBUFSIZ];
+           temp[0] = 0;
+           if ((home = getenv("HOME")) != 0  && *home != '\0'
+            && strchr(home, ' ') == 0
+            && strlen(home) < sizeof(temp) - 10) {     /* setup path */
+               sprintf(temp, "%s/", home);     /* $HOME first */
            }
+           /* if no $HOME look in current directory */
+           strcat(temp, ".termcap");
+           _nc_safe_strcat(&desc, temp);
            _nc_safe_strcat(&desc, " /etc/termcap");
            _nc_safe_strcat(&desc, " /usr/share/misc/termcap");
        }
@@ -930,7 +929,7 @@
     static char *source;
     static int lineno;
 
-    if ((p = getenv("TERMCAP")) != 0
+    if (use_terminfo_vars() && (p = getenv("TERMCAP")) != 0
        && !is_pathname(p) && _nc_name_match(p, tn, "|:")) {
        /* TERMCAP holds a termcap entry */
        strncpy(tc, p, sizeof(tc) - 1);
@@ -980,7 +979,7 @@
     char pathbuf[PATH_MAX];
 
     termpaths[filecount] = 0;
-    if ((tc = getenv("TERMCAP")) != 0) {
+    if (use_terminfo_vars() && (tc = getenv("TERMCAP")) != 0) {
        if (is_pathname(tc)) {  /* interpret as a filename */
            ADD_TC(tc, 0);
        } else if (_nc_name_match(tc, tn, "|:")) {      /* treat as a 
capability file */
@@ -1013,7 +1012,7 @@
 
 #define PRIVATE_CAP "%s/.termcap"
 
-       if ((h = getenv("HOME")) != NULL
+       if ((h = getenv("HOME")) != NULL && *h != '\0'
            && (strlen(h) + sizeof(PRIVATE_CAP)) < PATH_MAX) {
            /* user's .termcap, if any, should override it */
            (void) strcpy(envhome, h);
--- read_entry.c.DIST   Sat Oct  7 21:17:34 2000
+++ read_entry.c        Sun Oct  8 16:23:53 2000
@@ -79,7 +79,7 @@
        if (path != 0) {
            result = path;
            have_tic_directory = TRUE;
-       } else if (!have_tic_directory) {
+       } else if (!have_tic_directory && use_terminfo_vars()) {
            char *envp;
            if ((envp = getenv("TERMINFO")) != 0)
                return _nc_tic_dir(envp);