mruby-pack/pack.c (read_tmpl): support J/j template in pack

J/j is available since Ruby 2.3.

Author: matz

mrbgems/mruby-pack/README.md

@@ -28,6 +28,8 @@ There is no dependency on other mrbgems.
 - h : hex string (low nibble first)
 - I : unsigned integer, native endian (`unsigned int` in C)
 - i : signed integer, native endian (`int` in C)
+- J : unsigned integer, native endian (`uintptr_t` in C)
+- j : signed integer, native endian (`intptr_t` in C)
 - L : 32-bit unsigned, native endian (`uint32_t`)
 - l : 32-bit signed, native endian (`int32_t`)
 - m : base64 encoded string (see RFC 2045, count is width)

mrbgems/mruby-pack/src/pack.c

@@ -1219,6 +1219,22 @@ read_tmpl(mrb_state *mrb, struct tmpl *tmpl, enum pack_dir *dirp, enum pack_type
         mrb_raisef(mrb, E_RUNTIME_ERROR, "mruby-pack does not support sizeof(int) == %d", (int)sizeof(int));
     }
     break;
+  case 'J':
+    switch (sizeof(intptr_t)) {
+      case 4: t = 'L'; goto alias;
+      case 8: t = 'Q'; goto alias;
+      default:
+        mrb_raisef(mrb, E_RUNTIME_ERROR, "mruby-pack does not support sizeof(uintptr_t) == %d", (int)sizeof(uintptr_t));
+    }
+    break;
+  case 'j':
+    switch (sizeof(intptr_t)) {
+      case 4: t = 'l'; goto alias;
+      case 8: t = 'q'; goto alias;
+      default:
+        mrb_raisef(mrb, E_RUNTIME_ERROR, "mruby-pack does not support sizeof(intptr_t) == %d", (int)sizeof(intptr_t));
+    }
+    break;
   case 'L':
     dir = PACK_DIR_LONG;
     type = PACK_TYPE_INTEGER;