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LithosAnanake/include/starkernel/repl.h
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/*
StarForth — Steady-State Virtual Machine Runtime
Copyright (c) 20232025 Robert A. James
All rights reserved.
Licensed under the StarForth License, Version 1.0
*/
/**
* repl.h - Emergency FORTH REPL for LithosAnanke kernel
*/
#ifndef STARKERNEL_REPL_H
#define STARKERNEL_REPL_H
#include "vm.h"
#include "starkernel/homeblocks_sig.h"
struct blkio_dev;
#ifdef __cplusplus
extern "C" {
#endif
/**
* sk_repl - Run the emergency FORTH REPL on the serial console.
*
* Blocks until vm->halted is set (BYE word) or the VM encounters a halt.
* Runs with interrupts enabled; the APIC heartbeat continues to fire.
*
* @param vm Mama VM instance (must be fully initialised)
*/
void sk_repl(VM *vm);
/**
* sk_repl_run - Bare REPL loop (no banner).
*
* Same as sk_repl but skips the version/welcome banner. Used by START
* to enter a child VM's interpreter loop without reprinting the header.
*
* @param vm Fully initialised VM instance
*/
void sk_repl_run(VM *vm);
/**
* sk_repl_step - Execute one REPL turn on a VM and return.
*
* Prints the VM's prompt, reads one line, interprets it, prints ok/ERROR,
* then returns. Used by the Compudynamics VM-STEP primitive so Hera can
* give a single REPL quantum to a child VM without surrendering control
* for the full sk_repl_run() loop.
*
* @param vm Fully initialised VM instance
* @return 1 if the VM is still running, 0 if it halted during this turn
*/
int sk_repl_step(VM *vm);
/**
* sk_repl_set_active_vm - Redirect REPL input to a different VM (USE word).
*
* Pass NULL to restore default dispatch (Mama's VM).
* The change takes effect on the next REPL iteration.
*
* @param vm Target VM, or NULL for default
*/
void sk_repl_set_active_vm(VM *vm);
/**
* sk_repl_get_active_vm - Return the current USE-redirected VM, or NULL.
*/
VM *sk_repl_get_active_vm(void);
/**
* sk_repl_get_homeblocks_dev / sk_repl_get_homeblocks_sig - The currently
* attached home-blocks USB drive, or NULL if none is attached / the
* attached drive didn't check out as HOMEBLOCKS_SIG_OK (FABRIC-3.md
* §F.6/§F.9/§F.18). Both return NULL together; never one without the
* other.
*/
struct blkio_dev *sk_repl_get_homeblocks_dev(void);
const homeblocks_sig_t *sk_repl_get_homeblocks_sig(void);
/**
* sk_repl_get_attached_blk_dev - The currently attached USB block
* device, regardless of home-blocks recognition (FABRIC-3.md
* §F.8/§F.19) -- MINT's own target, since a blank/unminted drive never
* sets sk_repl_get_homeblocks_dev() above. NULL if nothing is attached.
*/
struct blkio_dev *sk_repl_get_attached_blk_dev(void);
/**
* sk_console_getkey - Real body of the standard dictionary's KEY word
* (called from shim.c's getchar()). Blocks until a key is available from
* either input source (serial console or the PS2/virtio keyboard-event
* bridge), servicing the heartbeat/idle loop while waiting so a KEY call
* from inside any word never stalls the heartbeat. No echo -- that's the
* caller's responsibility, same as any standard KEY.
*
* @param active_vm VM whose idle dispatch runs while waiting (see
* sk_repl_idle()'s own doc comment on why this is a
* parameter rather than read via sk_repl_get_active_vm())
* @return the key read, as an unsigned byte value
*/
int sk_console_getkey(VM *active_vm);
/**
* sk_console_key_available - Real body of the standard dictionary's
* ?TERMINAL word (called from sf_terminal_ready()). Non-blocking peek:
* returns 1 if a key is ready without consuming it (a following
* sk_console_getkey() returns that exact key), 0 otherwise.
*/
int sk_console_key_available(void);
/**
* sk_console_readline - Real body of the standard dictionary's
* QUERY/EXPECT words (called from shim.c's fgets()). Reads one line from
* the console with echo and backspace support, servicing the heartbeat/
* idle loop while waiting -- the same line editor the REPL's own prompt
* uses internally, so a mid-word EXPECT behaves identically to typing at
* "ok>" itself.
*
* @param buf Destination buffer
* @param size Buffer capacity, including the NUL terminator
* @param active_vm VM whose idle dispatch runs while waiting
* @param reanchor_prompt Nonzero to re-print the "ok> " prompt whenever
* an idle bottom half (heartbeat, USB attach/detach) writes
* to the console while this readline blocks at a bare,
* untyped prompt -- keeps the top-level prompt as the last
* thing shown once the chatter dies down. Callers whose
* prompt line is their own (shim.c's fgets(), i.e.
* QUERY/EXPECT/ACCEPT) pass 0 so "ok> " never gets stamped
* onto their mid-word input context.
* @return number of characters placed in buf, not counting the NUL
*/
int sk_console_readline(char* buf, int size, VM* active_vm, int reanchor_prompt);
#ifdef __cplusplus
}
#endif
#endif /* STARKERNEL_REPL_H */