Run command passed to if_not_there directly from Makefile.direct

Issue #199 (bdwgc).

if_not_there tool is modified to accept a single argument (file name).

* Makefile.direct (base_lib, cords, test_cpp, c++, mach_dep.o, mark_rts.o,
cord/cordtest, cord/de, gctest): Replace "if_not_there <file> <command>"
with "if_not_there <file> || <command>".
* Makefile.direct (c++): Add dependency on $(UTILS).
* Makefile.direct (gctest): Remove double spaces.
* tools/if_not_there.c: Update header comment.
* tools/if_not_there.c (main): Allow both 2 and 3 command-line arguments;
return 2 if the file does not exist and argc is 2; update the printed
usage message.

1 files changed, 9 insertions, 3 deletions

diff --git a/tools/if_not_there.c b/tools/if_not_there.c
index 190a5821..10f5d14a 100644
--- a/tools/if_not_there.c
+++ b/tools/if_not_there.c
@@ -1,4 +1,6 @@
-/* Conditionally execute a command based if the file argv[1] doesn't exist */
+/* Conditionally execute the command argv[2] based if the file argv[1]  */
+/* does not exist.  If the command is omitted (and the file does not    */
+/* exist) then just exit with a non-zero code.                          */
 
 # include "private/gc_priv.h"
 # include <stdio.h>
@@ -16,7 +18,8 @@ int main(int argc, char **argv)
 #endif /* __DJGPP__ */
     char *fname;
 
-    if (argc < 3) goto Usage;
+    if (argc < 2 || argc > 3)
+        goto Usage;
 
     fname = TRUSTED_STRING(argv[1]);
     f = fopen(fname, "rb");
@@ -37,10 +40,13 @@ int main(int argc, char **argv)
 #endif
     printf("^^^^Starting command^^^^\n");
     fflush(stdout);
+    if (argc == 2)
+        return(2); /* the file does not exist but no command is given */
+
     execvp(TRUSTED_STRING(argv[2]), (void *)(argv + 2));
     exit(1);
 
 Usage:
-    fprintf(stderr, "Usage: %s file_name command\n", argv[0]);
+    fprintf(stderr, "Usage: %s file_name [command]\n", argv[0]);
     return(1);
 }