1 files changed, 141 insertions, 0 deletions
diff --git a/prism/pack.h b/prism/pack.h
new file mode 100644
index 0000000000..9d6204bf7b
--- /dev/null
+++ b/prism/pack.h
@@ -0,0 +1,141 @@
+#ifndef YARP_PACK_H
+#define YARP_PACK_H
+
+#include "yarp/defines.h"
+
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef enum yp_pack_version {
+    YP_PACK_VERSION_3_2_0
+} yp_pack_version;
+
+typedef enum yp_pack_variant {
+    YP_PACK_VARIANT_PACK,
+    YP_PACK_VARIANT_UNPACK
+} yp_pack_variant;
+
+typedef enum yp_pack_type {
+    YP_PACK_SPACE,
+    YP_PACK_COMMENT,
+    YP_PACK_INTEGER,
+    YP_PACK_UTF8,
+    YP_PACK_BER,
+    YP_PACK_FLOAT,
+    YP_PACK_STRING_SPACE_PADDED,
+    YP_PACK_STRING_NULL_PADDED,
+    YP_PACK_STRING_NULL_TERMINATED,
+    YP_PACK_STRING_MSB,
+    YP_PACK_STRING_LSB,
+    YP_PACK_STRING_HEX_HIGH,
+    YP_PACK_STRING_HEX_LOW,
+    YP_PACK_STRING_UU,
+    YP_PACK_STRING_MIME,
+    YP_PACK_STRING_BASE64,
+    YP_PACK_STRING_FIXED,
+    YP_PACK_STRING_POINTER,
+    YP_PACK_MOVE,
+    YP_PACK_BACK,
+    YP_PACK_NULL,
+    YP_PACK_END
+} yp_pack_type;
+
+typedef enum yp_pack_signed {
+    YP_PACK_UNSIGNED,
+    YP_PACK_SIGNED,
+    YP_PACK_SIGNED_NA
+} yp_pack_signed;
+
+typedef enum yp_pack_endian {
+    YP_PACK_AGNOSTIC_ENDIAN,
+    YP_PACK_LITTLE_ENDIAN,      // aka 'VAX', or 'V'
+    YP_PACK_BIG_ENDIAN,         // aka 'network', or 'N'
+    YP_PACK_NATIVE_ENDIAN,
+    YP_PACK_ENDIAN_NA
+} yp_pack_endian;
+
+typedef enum yp_pack_size {
+    YP_PACK_SIZE_SHORT,
+    YP_PACK_SIZE_INT,
+    YP_PACK_SIZE_LONG,
+    YP_PACK_SIZE_LONG_LONG,
+    YP_PACK_SIZE_8,
+    YP_PACK_SIZE_16,
+    YP_PACK_SIZE_32,
+    YP_PACK_SIZE_64,
+    YP_PACK_SIZE_P,
+    YP_PACK_SIZE_NA
+} yp_pack_size;
+
+typedef enum yp_pack_length_type {
+    YP_PACK_LENGTH_FIXED,
+    YP_PACK_LENGTH_MAX,
+    YP_PACK_LENGTH_RELATIVE,  // special case for unpack @*
+    YP_PACK_LENGTH_NA
+} yp_pack_length_type;
+
+typedef enum yp_pack_encoding {
+    YP_PACK_ENCODING_START,
+    YP_PACK_ENCODING_ASCII_8BIT,
+    YP_PACK_ENCODING_US_ASCII,
+    YP_PACK_ENCODING_UTF_8
+} yp_pack_encoding;
+
+typedef enum yp_pack_result {
+    YP_PACK_OK,
+    YP_PACK_ERROR_UNSUPPORTED_DIRECTIVE,
+    YP_PACK_ERROR_UNKNOWN_DIRECTIVE,
+    YP_PACK_ERROR_LENGTH_TOO_BIG,
+    YP_PACK_ERROR_BANG_NOT_ALLOWED,
+    YP_PACK_ERROR_DOUBLE_ENDIAN
+} yp_pack_result;
+
+// Parse a single directive from a pack or unpack format string.
+//
+// Parameters:
+//  - [in] yp_pack_version version    the version of Ruby
+//  - [in] yp_pack_variant variant    pack or unpack
+//  - [in out] const char **format    the start of the next directive to parse
+//      on calling, and advanced beyond the parsed directive on return, or as
+//      much of it as was consumed until an error was encountered
+//  - [in] const char *format_end     the end of the format string
+//  - [out] yp_pack_type *type        the type of the directive
+//  - [out] yp_pack_signed *signed_type
+//                                    whether the value is signed
+//  - [out] yp_pack_endian *endian    the endianness of the value
+//  - [out] yp_pack_size *size        the size of the value
+//  - [out] yp_pack_length_type *length_type
+//                                    what kind of length is specified
+//  - [out] size_t *length            the length of the directive
+//  - [in out] yp_pack_encoding *encoding
+//                                    takes the current encoding of the string
+//      which would result from parsing the whole format string, and returns a
+//      possibly changed directive - the encoding should be
+//      YP_PACK_ENCODING_START when yp_pack_parse is called for the first
+//      directive in a format string
+//
+// Return:
+//  - YP_PACK_OK on success
+//  - YP_PACK_ERROR_* on error
+//
+// Notes:
+//   Consult Ruby documentation for the meaning of directives.
+YP_EXPORTED_FUNCTION yp_pack_result
+yp_pack_parse(
+    yp_pack_variant variant_arg,
+    const char **format,
+    const char *format_end,
+    yp_pack_type *type,
+    yp_pack_signed *signed_type,
+    yp_pack_endian *endian,
+    yp_pack_size *size,
+    yp_pack_length_type *length_type,
+    uint64_t *length,
+    yp_pack_encoding *encoding
+);
+
+// YARP abstracts sizes away from the native system - this converts an abstract
+// size to a native size.
+YP_EXPORTED_FUNCTION size_t yp_size_to_native(yp_pack_size size);
+
+#endif