Fix ./configure --with-filedescriptors=NUMBER (#1217)

Commit a1c2236 forgot to quote AS_CASE argument of AC_ARG_WITH(),
resulting in the following ./configure-time errors:

    error: --with-filedescriptors expects a numeric argument

We now quote AS_CASE argument of AC_ARG_WITH(), as recommended by
Autoconf and for consistency sake. More (hopefully automated) work is
needed to quote all function call arguments (that should be quoted).

Also use m4 quadrigraphs for quoting safety sake and to attract readers
attention to a risky (from writing in m4 point of view) expression. This
particular improvement is not required to fix the bug.

The other two AC_ARG_WITH() are modified for consistency sake but they
were not broken and their compiled versions have not changed.

diff --git a/configure.ac b/configure.ac
index ef3fa2284ec55ffd4b36f501dd95c6efd8256cca..635682d08e4b96577c57329711624a02562b4275 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -370,7 +370,7 @@ AC_ARG_WITH(aufs-threads,
   AS_HELP_STRING([--with-aufs-threads=N_THREADS],
     [Tune the number of worker threads for the aufs object store.]), [
   AS_CASE([$withval],
-    [[[0-9]]*],[squid_opt_aufs_threads=$withval],
+    [@<:@0-9@:>@*],[squid_opt_aufs_threads=$withval],
     AC_MSG_ERROR(--with-aufs-threads expects a numeric argument)
   )
 ])
@@ -2533,7 +2533,7 @@ dnl --with-maxfd present for compatibility with Squid-2.
 dnl undocumented in ./configure --help  to encourage using the Squid-3 directive
 AC_ARG_WITH(maxfd,,[
   AS_CASE([$withval],
-    [[[0-9]]*],[
+    [@<:@0-9@:>@*],[
       squid_filedescriptors_num=$withval
       AC_MSG_NOTICE([forcing default of $squid_filedescriptors_num filedescriptors (user-forced)])
     ],
@@ -2543,14 +2543,14 @@ AC_ARG_WITH(maxfd,,[
 
 AC_ARG_WITH(filedescriptors,
   AS_HELP_STRING([--with-filedescriptors=NUMBER],
-    [Force squid to support NUMBER filedescriptors]),
+    [Force squid to support NUMBER filedescriptors]),[
   AS_CASE([$withval],
-    [[[0-9]]*],[
+    [@<:@0-9@:>@*],[
       squid_filedescriptors_num=$withval
       AC_MSG_NOTICE([forcing default of $squid_filedescriptors_num filedescriptors (user-forced)])],
     [AC_MSG_ERROR([--with-filedescriptors expects a numeric argument])]
   )
-)
+])
 
 SQUID_CHECK_DEFAULT_FD_SETSIZE
 SQUID_CHECK_MAXFD