Unquote spawned command verbs on VMS.

Prior to the current change,

$ foo "A" "b" "c"

worked, but the following didn't:

$ "foo" "A" "b" "c"
%DCL-E-PARSEFAIL, error parsing DCL$PATH:"foo".*
-RMS-F-FNM, error in file name

even if foo was a valid command or path.  It's illegal in DCL to
quote the command verb even if it's often necessary to quote the
parameters to it.

But various things in the wild (such as Test::Harness::_filtered_inc),
find it convenient or necessary to quote the command verb, so the
easiest way to support that is to unquote it before DCL sees it, and
that's what this change does.

Also, spaces within the first quoted item are now escaped so that
an image path containing spaces doesn't run afoul of subsequent
tokenizing based on spaces.

diff --git a/vms/vms.c b/vms/vms.c
index a235a10..9777802 100644 (file)
--- a/vms/vms.c
+++ b/vms/vms.c
@@ -10467,6 +10467,68 @@ setup_cmddsc(pTHX_ const char *incmd, int check_img, int *suggest_quote,
     for (cp = &vmsspec[1]; *rest && isspace(*rest); rest++,cp++) *cp = *rest;
   }
   else { cp = vmsspec; rest = s; }
+
+  /* If the first word is quoted, then we need to unquote it and
+   * escape spaces within it.  We'll expand into the resspec buffer,
+   * then copy back into the cmd buffer, expanding the latter if
+   * necessary.
+   */
+  if (*rest == '"') {
+    char *cp2;
+    char *r = rest;
+    bool in_quote = 0;
+    int clen = cmdlen;
+    int soff = s - cmd;
+
+    for (cp2 = resspec;
+         *rest && cp2 - resspec < (VMS_MAXRSS - 1);
+         rest++) {
+
+      if (*rest == ' ') {    /* Escape ' ' to '^_'. */
+        *cp2 = '^';
+        *(++cp2) = '_';
+        cp2++;
+        clen++;
+      }
+      else if (*rest == '"') {
+        clen--;
+        if (in_quote) {     /* Must be closing quote. */
+          rest++;
+          break;
+        }
+        in_quote = 1;
+      }
+      else {
+        *cp2 = *rest;
+        cp2++;
+      }
+    }
+    *cp2 = '\0';
+
+    /* Expand the command buffer if necessary. */
+    if (clen > cmdlen) {
+      cmd = PerlMem_realloc(cmd, clen);
+      if (cmd == NULL)
+        _ckvmssts_noperl(SS$_INSFMEM);
+      /* Where we are may have changed, so recompute offsets */
+      r = cmd + (r - s - soff);
+      rest = cmd + (rest - s - soff);
+      s = cmd + soff;
+    }
+
+    /* Shift the non-verb portion of the command (if any) up or
+     * down as necessary.
+     */
+    if (*rest)
+      memmove(rest + clen - cmdlen, rest, s - soff + cmdlen - rest);
+
+    /* Copy the unquoted and escaped command verb into place. */
+    memcpy(r, resspec, cp2 - resspec); 
+    cmd[clen] = '\0';
+    cmdlen = clen;
+    rest = r;         /* Rewind for subsequent operations. */
+  }
+
   if (*rest == '.' || *rest == '/') {
     char *cp2;
     for (cp2 = resspec;