MightyPork
/
forth
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

add comments

Browse Source
master
Ondřej Hruška 3 years ago
parent c225928b54
commit 15848e203b
Signed by: MightyPork
GPG Key ID: 2C5FD5035250423D
4 changed files with 108 additions and 52 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 0
      a.forth
  2. 2
      hello.forth
  3. 150
      main.c
  4. 0
      str.forth

0
a.f → a.forth
Unescape View File

2
hello.forth
Unescape View File

@ -0,0 +1,2 @@
: hi ." Hello, World!" ;
hi

150
main.c
Unescape View File

@ -4,11 +4,12 @@
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#define CONTROL_STACK_DEPTH 1024
#define DATA_STACK_DEPTH 1024
#define RETURN_STACK_DEPTH 1024
#define MAX_NAME_LEN 64
#define MAX_NAME_LEN 32
#define DICT_SIZE 1024
#define COMPILED_BUFFER_SIZE (1024*1024)
#define HEAP_SIZE (1024*1024)
@ -18,27 +19,38 @@ struct fh_thread_s;
struct fh_word_s;
struct fh_instruction_s;
/** Forth runtime global state */
struct fh_global_s {
/** Verbose logging enabled */
bool verbose;
/** Interactive mode (i.e. not started with a file argument) */
bool interactive;
} fh_globals = {};
/* if the return address is this, we should drop back to interactive mode */
#define MAGICADDR_INTERACTIVE 0xFFFFFFFFULL
#define ALIGNWORD(var) \
do { \
while (((var) % 4) != 0) { (var)++; } \
} while (0)
/** Get a value rounded up to multiple of word size */
#define WORDALIGNED(var) (((var) + 3) & ~3)
_Static_assert(WORDALIGNED(0) == 0, "word align");
_Static_assert(WORDALIGNED(1) == 4, "word align");
_Static_assert(WORDALIGNED(2) == 4, "word align");
_Static_assert(WORDALIGNED(3) == 4, "word align");
_Static_assert(WORDALIGNED(4) == 4, "word align");
_Static_assert(WORDALIGNED(5) == 8, "word align");
_Static_assert(WORDALIGNED(1023) == 1024, "word align");
_Static_assert(WORDALIGNED(1024) == 1024, "word align");
/* logging, TODO make levels configurable */
/* logging */
#define LOG(format, ...) do { if(fh_globals.verbose) { fprintf(stderr, format "\r\n", ##__VA_ARGS__); } } while (0)
#define LOGI(format, ...) fprintf(stderr, "\x1b[32m" format "\x1b[m\r\n", ##__VA_ARGS__)
#define LOGE(format, ...) fprintf(stderr, "\x1b[31;1m" format "\x1b[m\r\n", ##__VA_ARGS__)
/* Forth standard output. XXX should be stdout, but then colors get mangled */
/* Forth standard output. XXX should be stdout, but then colors get mangled if logging is used */
#define FHPRINT(format, ...) fprintf(stderr, "\x1b[33;1m" format "\x1b[m", ##__VA_ARGS__)
#define FHPRINT_SVC(format, ...) fprintf(stderr, "" format "", ##__VA_ARGS__)
/** Error codes */
enum fh_error {
FH_OK = 0,
FH_ERR_CS_OVERFLOW,
@ -57,6 +69,7 @@ enum fh_error {
FH_ERR_MAX,
};
/** Error names */
static const char *errornames[] = {
[FH_OK] = "OK",
[FH_ERR_CS_OVERFLOW] = "CS_OVERFLOW",
@ -74,6 +87,7 @@ static const char *errornames[] = {
[FH_ERR_UNKNOWN_WORD] = "UNKNOWN_WORD",
};
/** Get error name from code, returns Unknown if not defined */
const char *fherr_name(enum fh_error e)
{
if (e >= FH_ERR_MAX) {
@ -82,39 +96,59 @@ const char *fherr_name(enum fh_error e)
return errornames[e];
}
/** Word handler typedef */
typedef enum fh_error (*word_exec_t)(struct fh_thread_s *fh);
/** Word struct as they are stored in the dictionary */
struct fh_word_s {
/** Word name */
char name[MAX_NAME_LEN];
/**
* Handler function.
* Builtin functions use pre-defined native handlers.
* User words use a shared handler that executes compiled
* bytecode at 'start' address of the compile-memory area.
*/
word_exec_t handler;
/** Indicates that this is a built-in instruction and not a word call */
bool builtin;
/** Indicates that this instruction should always be treated as interpreted,
* in practice this is only used for `;` */
bool immediate;
/** Start address in case of user words */
uint32_t start;
uint32_t end;
};
/** Bytecode instruction type marker */
enum fb_instruction_kind {
/* Data is a word number in the dict */
/* Data = word pointer (dict index) */
FH_INSTR_WORD,
/* Data is a numeric value to push on the data stack */
/* Data = numeric value to push onto the data stack */
FH_INSTR_NUMBER,
};
/** One instruction in bytecode */
struct fh_instruction_s {
/** What is the meaning of data? */
enum fb_instruction_kind kind;
/** Data word */
uint32_t data;
};
/** words that are not in the dict, have special effect */
/** Bytecode word indices that are not in the dict, have special effect */
enum compiler_word {
/** End of a user defined word, pop address and jump back */
CPLWORD_ENDWORD = DICT_SIZE + 1,
/** This is the `s"` instruction, the length (u32) and string data immediately follow */
CPLWORD_ALLOCSTR,
/** This is the `."` instruction, same format as above. */
CPLWORD_TYPESTR,
};
_Static_assert(sizeof(struct fh_instruction_s) % 4 == 0, "Instruction struct is aligned");
/** Forth runtime major state */
enum fh_state {
FH_STATE_INTERPRET = 0,
FH_STATE_COMPILE,
@ -122,12 +156,14 @@ enum fh_state {
FH_STATE_MAX,
};
/** State names */
static const char *statenames[] = {
[FH_STATE_INTERPRET] = "INTERPRET",
[FH_STATE_COMPILE] = "COMPILE",
[FH_STATE_SHUTDOWN] = "SHUTDOWN",
};
/** Forth runtime minor state */
enum fh_substate {
FH_SUBSTATE_NONE = 0,
FH_SUBSTATE_COLONNAME,
@ -138,6 +174,7 @@ enum fh_substate {
FH_SUBSTATE_MAX,
};
/** Sub-state names */
static const char *substatenames[] = {
[FH_SUBSTATE_NONE] = "NONE",
[FH_SUBSTATE_COLONNAME] = "COLONNAME",
@ -147,6 +184,12 @@ static const char *substatenames[] = {
[FH_SUBSTATE_LINECOMMENT] = "LINECOMMENT",
};
/**
* Forth runtime instance - state variables and memory areas.
*
* Some memory areas, such as the dict or heap, could be moved
* to a shared pointer if multi-threading and synchronization is added.
*/
struct fh_thread_s {
/** Control stack */
uint32_t control_stack[CONTROL_STACK_DEPTH];
@ -176,8 +219,10 @@ struct fh_thread_s {
/** Forth state */
enum fh_state state;
/** Forth sub-state */
enum fh_substate substate;
/** Word currently being executed - a pointer is placed here
* before calling the handler */
struct fh_word_s *exec_word;
@ -188,11 +233,6 @@ struct fh_thread_s {
if (FH_OK != (rv = (x))) return rv; \
} while (0)
#define TRY_FAIL(x) \
do { \
if (FH_OK != (rv = (x))) goto fail; \
} while (0)
/** Add a word to the dictionary. */
enum fh_error fh_add_word(const struct fh_word_s *w, struct fh_thread_s *fh)
{
@ -203,8 +243,7 @@ enum fh_error fh_add_word(const struct fh_word_s *w, struct fh_thread_s *fh)
return FH_OK;
}
//region Push & Pop
/** Pop from data stack */
static inline enum fh_error ds_pop(struct fh_thread_s *fh, uint32_t *out)
{
if (fh->data_stack_top == 0) {
@ -216,6 +255,7 @@ static inline enum fh_error ds_pop(struct fh_thread_s *fh, uint32_t *out)
return FH_OK;
}
/** Pop from return stack */
static inline enum fh_error rs_pop(struct fh_thread_s *fh, uint32_t *out)
{
if (fh->return_stack_top == 0) {
@ -227,6 +267,7 @@ static inline enum fh_error rs_pop(struct fh_thread_s *fh, uint32_t *out)
return FH_OK;
}
/** Pop from control stack */
static inline enum fh_error cs_pop(struct fh_thread_s *fh, uint32_t *out)
{
if (fh->control_stack_top == 0) {
@ -238,6 +279,7 @@ static inline enum fh_error cs_pop(struct fh_thread_s *fh, uint32_t *out)
return FH_OK;
}
/** Push to data stack */
static inline enum fh_error ds_push(struct fh_thread_s *fh, uint32_t in)
{
LOG("DS push %d", in);
@ -248,6 +290,7 @@ static inline enum fh_error ds_push(struct fh_thread_s *fh, uint32_t in)
return FH_OK;
}
/** Push to return stack */
static inline enum fh_error rs_push(struct fh_thread_s *fh, uint32_t in)
{
LOG("RS push %d", in);
@ -258,6 +301,7 @@ static inline enum fh_error rs_push(struct fh_thread_s *fh, uint32_t in)
return FH_OK;
}
/** Push to control stack */
static inline enum fh_error cs_push(struct fh_thread_s *fh, uint32_t in)
{
LOG("CS push %d", in);
@ -268,9 +312,9 @@ static inline enum fh_error cs_push(struct fh_thread_s *fh, uint32_t in)
return FH_OK;
}
//endregion Push & Pop
static void showstate(const struct fh_thread_s *fh) {
/** Log current runtime state */
static void showstate(const struct fh_thread_s *fh)
{
if (fh->substate == 0) {
LOG("state = %s", statenames[fh->state]);
} else {
@ -278,6 +322,7 @@ static void showstate(const struct fh_thread_s *fh) {
}
}
/** Set runtime state and sub-state */
void fh_setstate(struct fh_thread_s *fh, enum fh_state state, enum fh_substate substate)
{
fh->state = state;
@ -285,20 +330,21 @@ void fh_setstate(struct fh_thread_s *fh, enum fh_state state, enum fh_substate s
showstate(fh);
}
/** Set runtime sub-state (state is unchanged) */
void fh_setsubstate(struct fh_thread_s *fh, enum fh_substate substate)
{
fh->substate = substate;
showstate(fh);
}
enum fh_error fh_allot(
/** Allocate a heap region, e.g. for a string. The address is stored to `addr` */
enum fh_error fh_heap_reserve(
struct fh_thread_s *fh,
size_t len,
uint32_t *addr
)
{
uint32_t p = fh->heap_top;
ALIGNWORD(p);
uint32_t p = WORDALIGNED(fh->heap_top); // FIXME this shouldn't be needed
if (p + len > HEAP_SIZE) {
return FH_ERR_HEAP_FULL;
@ -306,22 +352,19 @@ enum fh_error fh_allot(
*addr = p;
size_t next = p + len;
ALIGNWORD(next);
fh->heap_top = next;
fh->heap_top = WORDALIGNED(p + len);
return FH_OK;
}
/** Reserve space in the compile memory area */
enum fh_error fh_compile_reserve(
struct fh_thread_s *fh,
size_t len,
uint32_t *addr
)
{
uint32_t p = fh->compile_top;
// align up
ALIGNWORD(p);
uint32_t p = WORDALIGNED(fh->compile_top); // FIXME this shouldn't be needed
if (p + len > COMPILED_BUFFER_SIZE) {
return FH_ERR_HEAP_FULL;
@ -329,16 +372,11 @@ enum fh_error fh_compile_reserve(
*addr = p;
size_t next = p + len;
ALIGNWORD(next);
fh->compile_top = next;
fh->compile_top = WORDALIGNED(p + len);
return FH_OK;
}
//region Builtin Words
enum fh_error w_add(struct fh_thread_s *fh)
{
enum fh_error rv;
@ -387,7 +425,7 @@ enum fh_error w_user_word(struct fh_thread_s *fh)
instr:;
// make sure it's aligned
ALIGNWORD(fh->execptr);
fh->execptr = WORDALIGNED(fh->execptr);
const struct fh_instruction_s *instr = (const struct fh_instruction_s *) &fh->compile[fh->execptr];
fh->execptr += sizeof(struct fh_instruction_s);
@ -406,7 +444,7 @@ enum fh_error w_user_word(struct fh_thread_s *fh)
strl = *((uint32_t *) &fh->compile[fh->execptr]);
fh->execptr += 4;
if (wn == CPLWORD_ALLOCSTR) {
TRY(fh_allot(fh, strl, &addr));
TRY(fh_heap_reserve(fh, strl, &addr));
memcpy(&fh->heap[addr], &fh->compile[fh->execptr], strl);
LOG("Exec: alloc-str \"%.*s\"", strl, &fh->heap[addr]);
TRY(ds_push(fh, addr));
@ -477,7 +515,6 @@ enum fh_error w_semicolon(struct fh_thread_s *fh)
/* Return to interpret state */
fh_setstate(fh, FH_STATE_INTERPRET, 0);
fh->dict[fh->dict_top].end = fh->compile_top; /* one past the end cell */
fh->dict_top++;
return FH_OK;
}
@ -505,12 +542,14 @@ enum fh_error w_type(struct fh_thread_s *fh)
enum fh_error w_cr(struct fh_thread_s *fh)
{
(void) fh;
FHPRINT("\r\n");
return FH_OK;
}
enum fh_error w_space(struct fh_thread_s *fh)
{
(void) fh;
FHPRINT(" ");
return FH_OK;
}
@ -546,6 +585,7 @@ enum fh_error w_bye(struct fh_thread_s *fh)
return FH_OK;
}
/** Add pointers to built-in word handlers to a runtime struct */
enum fh_error register_builtin_words(struct fh_thread_s *fh)
{
struct name_and_handler {
@ -575,6 +615,7 @@ enum fh_error register_builtin_words(struct fh_thread_s *fh)
{ /* end marker */ }
};
// foreach
struct fh_word_s w;
const struct name_and_handler *p = builtins;
enum fh_error rv;
@ -594,8 +635,7 @@ enum fh_error register_builtin_words(struct fh_thread_s *fh)
#undef ADDWORD
//endregion Builtin Words
/** Initialize a runtime */
enum fh_error fh_init_thread(struct fh_thread_s *fh)
{
enum fh_error rv;
@ -609,7 +649,8 @@ enum fh_error fh_init_thread(struct fh_thread_s *fh)
return FH_OK;
}
enum fh_error fh_handle_quoted_string(
/** Process a quoted string read from input */
static enum fh_error fh_handle_quoted_string(
struct fh_thread_s *fh,
char *start,
size_t len
@ -623,7 +664,7 @@ enum fh_error fh_handle_quoted_string(
if (fh->state == FH_STATE_INTERPRET) {
switch (fh->substate) {
case FH_SUBSTATE_SQUOTE:
TRY(fh_allot(fh, len, &addr));
TRY(fh_heap_reserve(fh, len, &addr));
memcpy(&fh->heap[addr], start, len);
TRY(ds_push(fh, addr));
TRY(ds_push(fh, len));
@ -653,7 +694,8 @@ enum fh_error fh_handle_quoted_string(
return FH_OK;
}
enum fh_error fh_handle_word(
/** Process a word read from input */
static enum fh_error fh_handle_word(
struct fh_thread_s *fh,
char *start,
size_t len
@ -700,37 +742,42 @@ enum fh_error fh_handle_word(
}
if (fh->state == FH_STATE_COMPILE) {
LOG("Compile number: %d", v);
LOG("Compile number: %ld", v);
TRY(fh_compile_reserve(fh, sizeof(struct fh_instruction_s), &addr));
instr.kind = FH_INSTR_NUMBER;
instr.data = (uint32_t) v;
memcpy(&fh->compile[addr], &instr, sizeof(struct fh_instruction_s));
} else {
/* interpret */
LOG("Interpret number: %d", v);
LOG("Interpret number: %ld", v);
TRY(ds_push(fh, (uint32_t) v));
}
return FH_OK;
}
/** True if the character is whitespace */
static inline bool iswhite(char c)
{
return c == ' ' || c == '\n' || c == '\t' || c == '\r';
}
/** True if the character is CR or LF */
static inline bool isnl(char c)
{
return c == '\n' || c == '\r';
}
enum fh_error fh_process_line(struct fh_thread_s *fh, char *linebuf)
/** Process a line read from input */
static enum fh_error fh_process_line(struct fh_thread_s *fh, char *linebuf)
{
enum fh_error rv;
char *rp = linebuf;
char c;
if (!fh_globals.interactive) {
LOGI("%s", linebuf);
}
while (0 != (c = *rp) && fh->state != FH_STATE_SHUTDOWN) {
/* end on newline */
@ -806,6 +853,9 @@ enum fh_error fh_process_line(struct fh_thread_s *fh, char *linebuf)
case FH_SUBSTATE_LINECOMMENT:
LOG("Discard line comment");
goto done; // just discard the rest
default:
LOGE("Bad substate %s", substatenames[fh->substate]);
}
}
done:
@ -825,7 +875,7 @@ int main(int argc, char *argv[])
}
fh_globals.verbose = false;
fh_globals.interactive = false;
fh_globals.interactive = isatty(STDIN_FILENO);
FILE *infile = stdin;
@ -876,8 +926,12 @@ int main(int argc, char *argv[])
FHPRINT_SVC(" ok\r\n");
} else {
LOGE("ERROR %s on line %d", fherr_name(rv), linecnt);
if (!fh_globals.interactive) {
return 1;
}
/* reset state */
fh_setstate(&fh, FH_STATE_INTERPRET, FH_SUBSTATE_NONE);
}
}
FHPRINT_SVC("Bye.\r\n");

0
str.f → str.forth
Unescape View File

Write Preview
Loading…
Cancel
Save