body_window.h

#ifndef WIRED_SRVLOOP_BODY_WINDOW_H
#define WIRED_SRVLOOP_BODY_WINDOW_H
 
#include "common/bytes/span/span.h"
#include "common/platform/sys/syscall.h"

#define BODYWIN_CAP 2048

enum {
  BODYWIN_OPEN = 0,    
  BODYWIN_DONE,        
  BODYWIN_REJECTED,    
  BODYWIN_FRAME_ERROR, 
  BODYWIN_FRAME_UNEXPECTED,
};

typedef int (*bodywin_sink)(void* ctx, wired_span chunk, int fin);

typedef struct {
  u64 base;    
  u64 left;    
  u64 fin_off; 
  u64 granted; 
  u8  have[BODYWIN_CAP / 8]; 
  u8  fin;                   
  u8  on;                    
  u8  is_data;               
  u8  state;                 
} bodywin;

void bodywin_land(bodywin* w, u8* buf, u64 off, wired_span data, int fin);

usz bodywin_frontier(const bodywin* w);

void bodywin_consume(bodywin* w, u8* buf, usz n);

int bodywin_pump(bodywin* w, u8* buf, bodywin_sink fn, void* ctx);

typedef int (*bodywin_capsule_fn)(void* ctx, u64 type, wired_span value);

#define BODYWIN_CAPSULE_CAP (16 + 4 + 1024)

typedef struct {
  u64 skip; 
  usz n;    
  u8  buf[BODYWIN_CAPSULE_CAP]; 
} bodywin_capq;

int bodywin_capsules(
    bodywin* w, u8* buf, bodywin_capq* q, bodywin_capsule_fn fn, void* ctx);

u64 bodywin_credit_due(bodywin* w);
 
#endif