Coverity CID#287601 Resource leak

This should fix another theoretical file descriptor leak. As with the
previous change it is unclear this can actually happen. But better safe
than sorry and this should eliminate a lint warning.

Author: krader1961

src/cmd/ksh93/sh/path.c

@@ -696,7 +696,7 @@ static_fn bool pwdinfpath(void) {
 //
 Pathcomp_t *path_absolute(Shell_t *shp, const char *name, Pathcomp_t *pp) {
     int isfun;
-    int f = -1;
+    int fd = -1;
     int noexec = 0;
     Pathcomp_t *oldpp;
     Namval_t *np;
@@ -813,18 +813,21 @@ Pathcomp_t *path_absolute(Shell_t *shp, const char *name, Pathcomp_t *pp) {
         }
         shp->bltin_dir = NULL;
         sh_stats(STAT_PATHS);
-        f = can_execute(shp, stkptr(shp->stk, PATH_OFFSET), isfun);
-        if (isfun && f >= 0 && (cp = strrchr(name, '.'))) {
+        fd = can_execute(shp, stkptr(shp->stk, PATH_OFFSET), isfun);
+        if (isfun && fd >= 0 && (cp = strrchr(name, '.'))) {
             *cp = 0;
-            if (nv_open(name, sh_subfuntree(shp, 1), NV_NOARRAY | NV_IDENT | NV_NOSCOPE)) f = -1;
+            if (nv_open(name, sh_subfuntree(shp, 1), NV_NOARRAY | NV_IDENT | NV_NOSCOPE)) {
+                sh_close(fd);
+                fd = -1;
+            }
             *cp = '.';
         }
-        if (isfun && f >= 0) {
+        if (isfun && fd >= 0) {
             nv_onattr(nv_open(name, sh_subfuntree(shp, 1), NV_NOARRAY | NV_IDENT | NV_NOSCOPE),
                       NV_LTOU | NV_FUNCTION);
-            funload(shp, f, name);
+            funload(shp, fd, name);
             return NULL;
-        } else if (f >= 0 && (oldpp->flags & PATH_STD_DIR)) {
+        } else if (fd >= 0 && (oldpp->flags & PATH_STD_DIR)) {
             int n = stktell(shp->stk);
             sfputr(shp->stk, "/bin/", -1);
             sfputr(shp->stk, name, 0);
@@ -837,16 +840,23 @@ Pathcomp_t *path_absolute(Shell_t *shp, const char *name, Pathcomp_t *pp) {
                 nv_setattr(np, nvflags);
             }
         }
-        if (!pp || f >= 0) break;
+        if (!pp || fd >= 0) break;
         if (errno != ENOENT) noexec = errno;
         // It's not clear this can actually happen but Coverity Scan says it is possible.
-        if (f != -1) sh_close(f);
+        // No unit test causes this condition to be true.
+        if (fd != -1) {
+            sh_close(fd);
+            fd = -1;
+        }
     }
 
-    if (f < 0) {
+    if (fd == -1) {
         shp->path_err = (noexec ? noexec : ENOENT);
         return NULL;
     }
+
+    // If we reach this point fd must be stdin (i.e., zero) since we intend to read the file.
+    assert(fd == 0);
     sfputc(shp->stk, 0);
     return oldpp;
 }

src/cmd/ksh93/tests/types.sh

@@ -574,8 +574,9 @@ unset z
 u_t -a x | read z
 [[ $z == unset ]]  && log_error 'unset discipline called on type creation'
 
-{ z=$($SHELL 2> /dev/null 'typeset -T foo; typeset -T') ;} 2> /dev/null
-[[ $z == 'typeset -T foo' ]] || log_error '"typeset -T foo; typeset -T" failed'
+expect='typeset -T foo'
+{ actual=$($SHELL 'typeset -T foo; typeset -T') ;}
+[[ $actual == $expect ]] || log_error '"typeset -T foo; typeset -T" failed' "$expect" "$actual"
 
 { z=$($SHELL 2> /dev/null 'typeset -T foo=bar; typeset -T') ;} 2> /dev/null
 [[ $z ]] && log_error '"typeset -T foo=bar" should not creates type foo'