forge.h

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/*
  Copyright 2008-2016 David Robillard <d@drobilla.net>
 
  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.
 
  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

 
#ifndef LV2_ATOM_FORGE_H
#define LV2_ATOM_FORGE_H

 
#include "lv2/atom/atom.h"
#include "lv2/atom/util.h"
#include "lv2/core/attributes.h"
#include "lv2/urid/urid.h"
 
#include <assert.h>
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
// Disable deprecation warnings for Blank and Resource
LV2_DISABLE_DEPRECATION_WARNINGS

typedef void* LV2_Atom_Forge_Sink_Handle;

typedef intptr_t LV2_Atom_Forge_Ref;

typedef LV2_Atom_Forge_Ref (*LV2_Atom_Forge_Sink)(
  LV2_Atom_Forge_Sink_Handle handle,
  const void*                buf,
  uint32_t                   size);

typedef LV2_Atom* (*LV2_Atom_Forge_Deref_Func)(
  LV2_Atom_Forge_Sink_Handle handle,
  LV2_Atom_Forge_Ref         ref);

typedef struct LV2_Atom_Forge_Frame {
  struct LV2_Atom_Forge_Frame* parent;
  LV2_Atom_Forge_Ref           ref;
} LV2_Atom_Forge_Frame;

typedef struct {
  uint8_t* buf;
  uint32_t offset;
  uint32_t size;
 
  LV2_Atom_Forge_Sink        sink;
  LV2_Atom_Forge_Deref_Func  deref;
  LV2_Atom_Forge_Sink_Handle handle;
 
  LV2_Atom_Forge_Frame* stack;
 
  LV2_URID Blank    LV2_DEPRECATED;
  LV2_URID          Bool;
  LV2_URID          Chunk;
  LV2_URID          Double;
  LV2_URID          Float;
  LV2_URID          Int;
  LV2_URID          Long;
  LV2_URID          Literal;
  LV2_URID          Object;
  LV2_URID          Path;
  LV2_URID          Property;
  LV2_URID Resource LV2_DEPRECATED;
  LV2_URID          Sequence;
  LV2_URID          String;
  LV2_URID          Tuple;
  LV2_URID          URI;
  LV2_URID          URID;
  LV2_URID          Vector;
} LV2_Atom_Forge;
 
static inline void
lv2_atom_forge_set_buffer(LV2_Atom_Forge* forge, uint8_t* buf, size_t size);

static inline void
lv2_atom_forge_init(LV2_Atom_Forge* forge, LV2_URID_Map* map)
{
  lv2_atom_forge_set_buffer(forge, NULL, 0);
  forge->Blank    = map->map(map->handle, LV2_ATOM__Blank);
  forge->Bool     = map->map(map->handle, LV2_ATOM__Bool);
  forge->Chunk    = map->map(map->handle, LV2_ATOM__Chunk);
  forge->Double   = map->map(map->handle, LV2_ATOM__Double);
  forge->Float    = map->map(map->handle, LV2_ATOM__Float);
  forge->Int      = map->map(map->handle, LV2_ATOM__Int);
  forge->Long     = map->map(map->handle, LV2_ATOM__Long);
  forge->Literal  = map->map(map->handle, LV2_ATOM__Literal);
  forge->Object   = map->map(map->handle, LV2_ATOM__Object);
  forge->Path     = map->map(map->handle, LV2_ATOM__Path);
  forge->Property = map->map(map->handle, LV2_ATOM__Property);
  forge->Resource = map->map(map->handle, LV2_ATOM__Resource);
  forge->Sequence = map->map(map->handle, LV2_ATOM__Sequence);
  forge->String   = map->map(map->handle, LV2_ATOM__String);
  forge->Tuple    = map->map(map->handle, LV2_ATOM__Tuple);
  forge->URI      = map->map(map->handle, LV2_ATOM__URI);
  forge->URID     = map->map(map->handle, LV2_ATOM__URID);
  forge->Vector   = map->map(map->handle, LV2_ATOM__Vector);
}

static inline LV2_Atom*
lv2_atom_forge_deref(LV2_Atom_Forge* forge, LV2_Atom_Forge_Ref ref)
{
  return forge->buf ? (LV2_Atom*)ref : forge->deref(forge->handle, ref);
}


static inline LV2_Atom_Forge_Ref
lv2_atom_forge_push(LV2_Atom_Forge*       forge,
                    LV2_Atom_Forge_Frame* frame,
                    LV2_Atom_Forge_Ref    ref)
{
  frame->parent = forge->stack;
  frame->ref    = ref;
 
  if (ref) {
    forge->stack = frame; // Don't push, so walking the stack is always safe
  }
 
  return ref;
}

static inline void
lv2_atom_forge_pop(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame)
{
  if (frame->ref) {
    // If frame has a valid ref, it must be the top of the stack
    assert(frame == forge->stack);
    forge->stack = frame->parent;
  }
  // Otherwise, frame was not pushed because of overflow, do nothing
}

static inline bool
lv2_atom_forge_top_is(LV2_Atom_Forge* forge, uint32_t type)
{
  return forge->stack && forge->stack->ref &&
         (lv2_atom_forge_deref(forge, forge->stack->ref)->type == type);
}

static inline bool
lv2_atom_forge_is_object_type(const LV2_Atom_Forge* forge, uint32_t type)
{
  return (type == forge->Object || type == forge->Blank ||
          type == forge->Resource);
}

static inline bool
lv2_atom_forge_is_blank(const LV2_Atom_Forge*       forge,
                        uint32_t                    type,
                        const LV2_Atom_Object_Body* body)
{
  return (type == forge->Blank || (type == forge->Object && body->id == 0));
}


static inline void
lv2_atom_forge_set_buffer(LV2_Atom_Forge* forge, uint8_t* buf, size_t size)
{
  forge->buf    = buf;
  forge->size   = (uint32_t)size;
  forge->offset = 0;
  forge->deref  = NULL;
  forge->sink   = NULL;
  forge->handle = NULL;
  forge->stack  = NULL;
}

static inline void
lv2_atom_forge_set_sink(LV2_Atom_Forge*            forge,
                        LV2_Atom_Forge_Sink        sink,
                        LV2_Atom_Forge_Deref_Func  deref,
                        LV2_Atom_Forge_Sink_Handle handle)
{
  forge->buf  = NULL;
  forge->size = forge->offset = 0;
  forge->deref                = deref;
  forge->sink                 = sink;
  forge->handle               = handle;
  forge->stack                = NULL;
}


static inline LV2_Atom_Forge_Ref
lv2_atom_forge_raw(LV2_Atom_Forge* forge, const void* data, uint32_t size)
{
  LV2_Atom_Forge_Ref out = 0;
  if (forge->sink) {
    out = forge->sink(forge->handle, data, size);
  } else {
    out          = (LV2_Atom_Forge_Ref)forge->buf + forge->offset;
    uint8_t* mem = forge->buf + forge->offset;
    if (forge->offset + size > forge->size) {
      return 0;
    }
    forge->offset += size;
    memcpy(mem, data, size);
  }
  for (LV2_Atom_Forge_Frame* f = forge->stack; f; f = f->parent) {
    lv2_atom_forge_deref(forge, f->ref)->size += size;
  }
  return out;
}

static inline void
lv2_atom_forge_pad(LV2_Atom_Forge* forge, uint32_t written)
{
  const uint64_t pad      = 0;
  const uint32_t pad_size = lv2_atom_pad_size(written) - written;
  lv2_atom_forge_raw(forge, &pad, pad_size);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_write(LV2_Atom_Forge* forge, const void* data, uint32_t size)
{
  LV2_Atom_Forge_Ref out = lv2_atom_forge_raw(forge, data, size);
  if (out) {
    lv2_atom_forge_pad(forge, size);
  }
  return out;
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_string_body(LV2_Atom_Forge* forge, const char* str, uint32_t len)
{
  LV2_Atom_Forge_Ref out = lv2_atom_forge_raw(forge, str, len);
  if (out && (out = lv2_atom_forge_raw(forge, "", 1))) {
    lv2_atom_forge_pad(forge, len + 1);
  }
  return out;
}


static inline LV2_Atom_Forge_Ref
lv2_atom_forge_atom(LV2_Atom_Forge* forge, uint32_t size, uint32_t type)
{
  const LV2_Atom a = {size, type};
  return lv2_atom_forge_raw(forge, &a, sizeof(a));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_primitive(LV2_Atom_Forge* forge, const LV2_Atom* a)
{
  return (
    lv2_atom_forge_top_is(forge, forge->Vector)
      ? lv2_atom_forge_raw(forge, LV2_ATOM_BODY_CONST(a), a->size)
      : lv2_atom_forge_write(forge, a, (uint32_t)sizeof(LV2_Atom) + a->size));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_int(LV2_Atom_Forge* forge, int32_t val)
{
  const LV2_Atom_Int a = {{sizeof(val), forge->Int}, val};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_long(LV2_Atom_Forge* forge, int64_t val)
{
  const LV2_Atom_Long a = {{sizeof(val), forge->Long}, val};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_float(LV2_Atom_Forge* forge, float val)
{
  const LV2_Atom_Float a = {{sizeof(val), forge->Float}, val};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_double(LV2_Atom_Forge* forge, double val)
{
  const LV2_Atom_Double a = {{sizeof(val), forge->Double}, val};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_bool(LV2_Atom_Forge* forge, bool val)
{
  const LV2_Atom_Bool a = {{sizeof(int32_t), forge->Bool}, val ? 1 : 0};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_urid(LV2_Atom_Forge* forge, LV2_URID id)
{
  const LV2_Atom_URID a = {{sizeof(id), forge->URID}, id};
  return lv2_atom_forge_primitive(forge, &a.atom);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_typed_string(LV2_Atom_Forge* forge,
                            uint32_t        type,
                            const char*     str,
                            uint32_t        len)
{
  const LV2_Atom_String a   = {{len + 1, type}};
  LV2_Atom_Forge_Ref    out = lv2_atom_forge_raw(forge, &a, sizeof(a));
  if (out) {
    if (!lv2_atom_forge_string_body(forge, str, len)) {
      LV2_Atom* atom = lv2_atom_forge_deref(forge, out);
      atom->size = atom->type = 0;
      out                     = 0;
    }
  }
  return out;
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_string(LV2_Atom_Forge* forge, const char* str, uint32_t len)
{
  return lv2_atom_forge_typed_string(forge, forge->String, str, len);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_uri(LV2_Atom_Forge* forge, const char* uri, uint32_t len)
{
  return lv2_atom_forge_typed_string(forge, forge->URI, uri, len);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_path(LV2_Atom_Forge* forge, const char* path, uint32_t len)
{
  return lv2_atom_forge_typed_string(forge, forge->Path, path, len);
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_literal(LV2_Atom_Forge* forge,
                       const char*     str,
                       uint32_t        len,
                       uint32_t        datatype,
                       uint32_t        lang)
{
  const LV2_Atom_Literal a = {
    {(uint32_t)(sizeof(LV2_Atom_Literal) - sizeof(LV2_Atom) + len + 1),
     forge->Literal},
    {datatype, lang}};
  LV2_Atom_Forge_Ref out = lv2_atom_forge_raw(forge, &a, sizeof(a));
  if (out) {
    if (!lv2_atom_forge_string_body(forge, str, len)) {
      LV2_Atom* atom = lv2_atom_forge_deref(forge, out);
      atom->size = atom->type = 0;
      out                     = 0;
    }
  }
  return out;
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_vector_head(LV2_Atom_Forge*       forge,
                           LV2_Atom_Forge_Frame* frame,
                           uint32_t              child_size,
                           uint32_t              child_type)
{
  const LV2_Atom_Vector a = {{sizeof(LV2_Atom_Vector_Body), forge->Vector},
                             {child_size, child_type}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_vector(LV2_Atom_Forge* forge,
                      uint32_t        child_size,
                      uint32_t        child_type,
                      uint32_t        n_elems,
                      const void*     elems)
{
  const LV2_Atom_Vector a = {
    {(uint32_t)(sizeof(LV2_Atom_Vector_Body) + n_elems * child_size),
     forge->Vector},
    {child_size, child_type}};
  LV2_Atom_Forge_Ref out = lv2_atom_forge_write(forge, &a, sizeof(a));
  if (out) {
    lv2_atom_forge_write(forge, elems, child_size * n_elems);
  }
  return out;
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_tuple(LV2_Atom_Forge* forge, LV2_Atom_Forge_Frame* frame)
{
  const LV2_Atom_Tuple a = {{0, forge->Tuple}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_object(LV2_Atom_Forge*       forge,
                      LV2_Atom_Forge_Frame* frame,
                      LV2_URID              id,
                      LV2_URID              otype)
{
  const LV2_Atom_Object a = {
    {(uint32_t)sizeof(LV2_Atom_Object_Body), forge->Object}, {id, otype}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

LV2_DEPRECATED
static inline LV2_Atom_Forge_Ref
lv2_atom_forge_resource(LV2_Atom_Forge*       forge,
                        LV2_Atom_Forge_Frame* frame,
                        LV2_URID              id,
                        LV2_URID              otype)
{
  const LV2_Atom_Object a = {
    {(uint32_t)sizeof(LV2_Atom_Object_Body), forge->Resource}, {id, otype}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

LV2_DEPRECATED
static inline LV2_Atom_Forge_Ref
lv2_atom_forge_blank(LV2_Atom_Forge*       forge,
                     LV2_Atom_Forge_Frame* frame,
                     uint32_t              id,
                     LV2_URID              otype)
{
  const LV2_Atom_Object a = {
    {(uint32_t)sizeof(LV2_Atom_Object_Body), forge->Blank}, {id, otype}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_key(LV2_Atom_Forge* forge, LV2_URID key)
{
  const LV2_Atom_Property_Body a = {key, 0, {0, 0}};
  return lv2_atom_forge_write(forge, &a, 2 * (uint32_t)sizeof(uint32_t));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_property_head(LV2_Atom_Forge* forge,
                             LV2_URID        key,
                             LV2_URID        context)
{
  const LV2_Atom_Property_Body a = {key, context, {0, 0}};
  return lv2_atom_forge_write(forge, &a, 2 * (uint32_t)sizeof(uint32_t));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_sequence_head(LV2_Atom_Forge*       forge,
                             LV2_Atom_Forge_Frame* frame,
                             uint32_t              unit)
{
  const LV2_Atom_Sequence a = {
    {(uint32_t)sizeof(LV2_Atom_Sequence_Body), forge->Sequence}, {unit, 0}};
  return lv2_atom_forge_push(
    forge, frame, lv2_atom_forge_write(forge, &a, sizeof(a)));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_frame_time(LV2_Atom_Forge* forge, int64_t frames)
{
  return lv2_atom_forge_write(forge, &frames, sizeof(frames));
}

static inline LV2_Atom_Forge_Ref
lv2_atom_forge_beat_time(LV2_Atom_Forge* forge, double beats)
{
  return lv2_atom_forge_write(forge, &beats, sizeof(beats));
}
 
LV2_RESTORE_WARNINGS
 
#ifdef __cplusplus
} /* extern "C" */
#endif

 
#endif /* LV2_ATOM_FORGE_H */