Appropriate short-circuit for shell commands. Fixes #4361.

The original logic was a bad port of the following C code: ```c static const char posix_sh_cmds[][9] = { ... } if (first.len > 0 && first.len <= sizeof(posix_sh_cmds[0]) && ... ``` In C, the array allocation sets all elements to be sizeof = 9, even though most terminate via null at a shorter C string length. The check here is to filter out any commands longer than those known to be shell commands; my fix is to just have that max length be a constant and reference it where sizeof is used in MRI.
jruby · Dec 6, 2016 · 69da0af · 69da0af
1 parent 3a7b5a2
commit 69da0af
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/core/src/main/java/org/jruby/util/io/PopenExecutor.java b/core/src/main/java/org/jruby/util/io/PopenExecutor.java
@@ -1729,6 +1729,7 @@ public static RubyString checkArgv(ThreadContext context, IRubyObject[] argv) {
         return prog;
     }
 
+    private static final int posix_sh_cmd_length = 8;
     private static final String posix_sh_cmds[] = {
             "!",		/* reserved */
             ".",		/* special built-in */
@@ -1855,7 +1856,7 @@ else if (progByteList.get(p) == '/'){
                 }
                 if (!has_meta && first.getUnsafeBytes() != DUMMY_ARRAY) {
                     if (first.length() == 0) first.setRealSize(p - first.getBegin());
-                    if (first.length() > 0 && first.length() <= posix_sh_cmds[0].length() &&
+                    if (first.length() > 0 && first.length() <= posix_sh_cmd_length &&
                         Arrays.binarySearch(posix_sh_cmds, first.toString(), StringComparator.INSTANCE) >= 0)
                         has_meta = true;
                 }