Many fixes; now prints the prompt and gets as far as reading text from

the user.

diff --git a/Applications/util/fforth.c b/Applications/util/fforth.c
index a3547a9..39ca398 100644 (file)
--- a/Applications/util/fforth.c
+++ b/Applications/util/fforth.c
@@ -100,7 +100,6 @@ static cell_t* dsp;
 static cell_t rstack[RSTACKSIZE];
 static cell_t* rsp;
 
-static char pad[MAX_LINE_LENGTH];
 static char tib[MAX_LINE_LENGTH];
 static cell_t tib_h = MAX_LINE_LENGTH;
 static cell_t tibo = 0;
@@ -160,9 +159,9 @@ static void rpush(cell_t val)
 
 static cell_t rpop(void)
 {
-       if (dsp == &dstack[0])
+       if (rsp == &rstack[0])
                panic("return stack underflow");
-       return *--dsp;
+       return *--rsp;
 }
 
 static void* claim_workspace(size_t length)
@@ -199,24 +198,19 @@ static void codeword(cdefn_t* w)
        pc = (void*) w->payload;
 }
 
-static void sysvarword(cdefn_t* w)
-{
-       dpush((cell_t) w->payload);
-}
-
-static void indvarword(cdefn_t* w)
-{
-       cell_t* p = (void*) dpop();
-       dpush(*p);
-}
-
-static void varword(cdefn_t* w)
-{
-       dpush((cell_t) &w->payload);
-}
+static void rvarword(cdefn_t* w) { dpush((cell_t) w->payload); }
+static void wvarword(defn_t* w) { w->payload = (void*) dpop(); }
+static void rivarword(cdefn_t* w) { dpush(*(cell_t*) w->payload); }
+static void wivarword(cdefn_t* w) { *(cell_t*)w->payload = dpop(); }
 
 /* Forward declarations of words go here --- do not edit.*/
 //@EXPORT{
+static cdefn_t _exit_word;
+static cdefn_t _fputc_word;
+static cdefn_t _fwrite_word;
+static cdefn_t _stderr_word;
+static cdefn_t _stdin_word;
+static cdefn_t _stdout_word;
 static cdefn_t accept_word;
 static cdefn_t add_word;
 static cdefn_t allot_word;
@@ -236,8 +230,6 @@ static cdefn_t dot_quote_rword;
 static cdefn_t emit_word;
 static cdefn_t execute_word;
 static cdefn_t exit_word;
-static cdefn_t fputc_word;
-static cdefn_t fwrite_word;
 static cdefn_t here_word;
 static cdefn_t in_a_word;
 static cdefn_t latest_word;
@@ -249,16 +241,12 @@ static cdefn_t pad_word;
 static cdefn_t pling_word;
 static cdefn_t pop_word;
 static cdefn_t quit_word;
-static cdefn_t return_word;
 static cdefn_t rsp0_word;
 static cdefn_t rsp_at_word;
 static cdefn_t rsp_pling_word;
 static cdefn_t sp0_word;
 static cdefn_t sp_at_word;
 static cdefn_t sp_pling_word;
-static cdefn_t stderr_word;
-static cdefn_t stdin_word;
-static cdefn_t stdout_word;
 static cdefn_t sub_word;
 static cdefn_t tib_h_word;
 static cdefn_t tib_word;
@@ -266,12 +254,12 @@ static cdefn_t type_word;
 static cdefn_t zero_word;
 //@EXPORT}
 
-static void fwrite_cb(cdefn_t* w)
+static void _fwrite_cb(cdefn_t* w)
 {
        FILE* fp = (FILE*)dpop();
-       size_t n = dpop();
+       size_t len = dpop();
        void* ptr = (void*)dpop();
-       dpush(fwrite(ptr, 1, n, fp));
+       dpush(fwrite(ptr, 1, len, fp));
 }
 
 static void accept_cb(cdefn_t* w)
@@ -303,96 +291,95 @@ static void dot_quote_rcb(cdefn_t* w)
        pc = alignup(ptr+len+1);
 }
 
+static void _exit_cb(cdefn_t* w)    { exit(dpop()); }
+static void _fputc_cb(cdefn_t* w)   { FILE* fp = (FILE*)dpop(); fputc(dpop(), fp); }
 static void add_cb(cdefn_t* w)      { dpush(dpop() + dpop()); }
 static void allot_cb(cdefn_t* w)    { claim_workspace(dpop()); }
 static void at_cb(cdefn_t* w)       { dpush(*(cell_t*)dpop()); }
+static void branch_cb(cdefn_t* w)   { pc = (void*) *pc; }
+static void branchif_cb(cdefn_t* w) { if (dpop() == (cell_t)w->payload) pc = (void*)*pc; else pc++; }
 static void c_at_cb(cdefn_t* w)     { dpush(*(uint8_t*)dpop()); }
 static void c_pling_cb(cdefn_t* w)  { uint8_t* p = (uint8_t*)dpop(); *p = dpop(); }
 static void div_cb(cdefn_t* w)      { cell_t a = dpop(); cell_t b = dpop(); dpush(b / a); }
 static void execute_cb(cdefn_t* w)  { cdefn_t* p = (void*) dpop(); codeword(p); }
-static void exit_cb(cdefn_t* w)     { exit(dpop()); }
-static void fputc_cb(cdefn_t* w)    { FILE* fp = (FILE*)dpop(); fputc(dpop(), fp); }
-static void here_cb(cdefn_t* w)     { dpush((cell_t) here); }
+static void exit_cb(cdefn_t* w)     { pc = (void*)rpop(); }
 static void lit_cb(cdefn_t* w)      { dpush((cell_t) *pc++); }
 static void mul_cb(cdefn_t* w)      { dpush(dpop() * dpop()); }
-static void pad_cb(cdefn_t* w)      { dpush((cell_t) pad); }
 static void pling_cb(cdefn_t* w)    { cell_t* p = (cell_t*)dpop(); *p = dpop(); }
 static void pop_cb(cdefn_t* w)      { dpop(); }
-static void return_cb(cdefn_t* w)   { pc = (void*) rpop(); }
 static void sub_cb(cdefn_t* w)      { cell_t a = dpop(); cell_t b = dpop(); dpush(b - a); }
-static void branchif_cb(cdefn_t* w) { void* iftrue = (void*) *pc++; if (dpop() == (cell_t)w->payload) pc = iftrue; }
-static void branch_cb(cdefn_t* w)   { pc = (void*) *pc; }
-static void sp_pling_cb(cdefn_t* w) { dsp = (void*)dpop(); }
-static void rsp_pling_cb(cdefn_t* w) { rsp = (void*)dpop(); }
 
 static cdefn_t* bye_ops[] =     { &zero_word, &exit_word };
 static cdefn_t* c_comma_ops[] = { &here_word, &c_pling_word, &one_word, &allot_word, &exit_word };
 static cdefn_t* cells_ops[] =   { &cell_word, &mul_word, &exit_word };
 static cdefn_t* comma_ops[] =   { &here_word, &pling_word, &cell_word, &allot_word, &exit_word };
-static cdefn_t* emit_ops[] =    { &stdout_word, &fputc_word, &exit_word };
-static cdefn_t* type_ops[] =    { &stdout_word, &fwrite_word, &pop_word, &exit_word };
+static cdefn_t* emit_ops[] =    { &_stdout_word, &_fputc_word, &exit_word };
+static cdefn_t* type_ops[] =    { &_stdout_word, &_fwrite_word, &pop_word, &exit_word };
 
+static const char prompt_msg[4] = " ok\n";
 static cdefn_t* quit_ops[] =
 {
        /* Reset stacks. */
        &sp0_word, &sp_pling_word,
        &rsp0_word, &rsp_pling_word,
+       /* Display the prompt. */
+       &lit_word, (void*)prompt_msg, &lit_word, (void*)4, &type_word,
        /* Read a line from the terminal. */
        &tib_word, &tib_h_word, &accept_word,
        /* And go round again */
-       &branch_word, (void*)quit_ops
+       &branch_word, (void*)(quit_ops+4)
 };
 
 /* List of words go here. To add a word, add a new entry and run this file as
  * a shell script. The link field will be set correctly. 
  * BEWARE: these lines are parsed using whitespace. LEAVE EXACTLY AS IS.*/
-static cdefn_t accept_word =     { accept_cb,     "accept",  NULL,          NULL }; //@W
+static cdefn_t _exit_word =      { _exit_cb,      "_exit",   NULL,          NULL }; //@W
+static cdefn_t _fputc_word =     { _fputc_cb,     "_fputc",  &_exit_word,   NULL }; //@W
+static cdefn_t _fwrite_word =    { _fwrite_cb,    "_fwrite", &_fputc_word,  NULL }; //@W
+static cdefn_t _stderr_word =    { rivarword,     "_stderr", &_fwrite_word, &stderr, }; //@W
+static cdefn_t _stdin_word =     { rivarword,     "_stdin",  &_stderr_word, &stdin, }; //@W
+static cdefn_t _stdout_word =    { rivarword,     "_stdout", &_stdin_word,  &stdout, }; //@W
+static cdefn_t accept_word =     { accept_cb,     "accept",  &_stdout_word, NULL }; //@W
 static cdefn_t add_word =        { add_cb,        "+",       &accept_word,  NULL }; //@W
 static cdefn_t allot_word =      { allot_cb,      "allot",   &add_word,     NULL, }; //@W
 static cdefn_t at_word =         { at_cb,         "@",       &allot_word,   NULL }; //@W
-static cdefn_t base_word =       { sysvarword,    "base",    &at_word,      &base }; //@W
+static cdefn_t base_word =       { rvarword,      "base",    &at_word,      &base }; //@W
 static cdefn_t branch_word =     { branch_cb,     NULL,      &base_word,    (void*)0 }; //@W
 static cdefn_t branchif_word =   { branchif_cb,   NULL,      &branch_word,  (void*)0 }; //@W
 static cdefn_t bye_word =        { codeword,      "bye",     &branchif_word, bye_ops, }; //@W
 static cdefn_t c_at_word =       { c_at_cb,       "c@",      &bye_word,     NULL }; //@W
 static cdefn_t c_comma_word =    { codeword,      "c,",      &c_at_word,    c_comma_ops, }; //@W
 static cdefn_t c_pling_word =    { c_pling_cb,    "c!",      &c_comma_word, NULL }; //@W
-static cdefn_t cell_word =       { sysvarword,    "cell",    &c_pling_word, (void*)CELL, }; //@W
+static cdefn_t cell_word =       { rvarword,      "cell",    &c_pling_word, (void*)CELL, }; //@W
 static cdefn_t cells_word =      { codeword,      "cells",   &cell_word,    cells_ops, }; //@W
 static cdefn_t comma_word =      { codeword,      ",",       &cells_word,   comma_ops, }; //@W
 static cdefn_t div_word =        { div_cb,        "/",       &comma_word,   NULL }; //@W
 static cdefn_t dot_quote_rword = { dot_quote_rcb, NULL,      &div_word,     NULL }; //@W
 static cdefn_t emit_word =       { codeword,      "emit",    &dot_quote_rword, emit_ops }; //@W
 static cdefn_t execute_word =    { execute_cb,    "execute", &emit_word,    NULL }; //@W
-static cdefn_t exit_word =       { exit_cb,       "_exit",   &execute_word, NULL }; //@W
-static cdefn_t fputc_word =      { fputc_cb,      "_fwrite", &exit_word,    NULL }; //@W
-static cdefn_t fwrite_word =     { fwrite_cb,     "_fwrite", &fputc_word,   NULL }; //@W
-static cdefn_t here_word =       { here_cb,       "here",    &fwrite_word,  NULL, }; //@W
-static cdefn_t in_a_word =       { sysvarword,    ">in",     &here_word,    &tibo }; //@W
-static cdefn_t latest_word =     { indvarword,    "latest",  &in_a_word,    &latest, }; //@W
+static cdefn_t exit_word =       { exit_cb,       "exit",    &execute_word, NULL }; //@W
+static cdefn_t here_word =       { rivarword,     "here",    &exit_word,    &here }; //@W
+static cdefn_t in_a_word =       { rvarword,      ">in",     &here_word,    &tibo }; //@W
+static cdefn_t latest_word =     { rivarword,     "latest",  &in_a_word,    &latest, }; //@W
 static cdefn_t lit_word =        { lit_cb,        NULL,      &latest_word,  NULL, }; //@W
-static cdefn_t m_one_word =      { sysvarword,    "-1",      &lit_word,     (void*)-1, }; //@W
+static cdefn_t m_one_word =      { rvarword,      "-1",      &lit_word,     (void*)-1, }; //@W
 static cdefn_t mul_word =        { mul_cb,        "*",       &m_one_word,   NULL }; //@W
-static cdefn_t one_word =        { sysvarword,    "1",       &mul_word,     (void*)1, }; //@W
-static cdefn_t pad_word =        { pad_cb,        "pad",     &one_word,     NULL }; //@W
+static cdefn_t one_word =        { rvarword,      "1",       &mul_word,     (void*)1, }; //@W
+static cdefn_t pad_word =        { rvarword,      "pad",     &one_word,     &here }; //@W
 static cdefn_t pling_word =      { pling_cb,      "!",       &pad_word,     NULL }; //@W
 static cdefn_t pop_word =        { pop_cb,        "pop",     &pling_word,   NULL }; //@W
 static cdefn_t quit_word =       { codeword,      NULL,      &pop_word,     quit_ops }; //@W
-static cdefn_t return_word =     { return_cb,     ";",       &quit_word,    NULL, }; //@W
-static cdefn_t rsp0_word =       { sysvarword,    "rsp0",    &return_word,  rstack }; //@W
-static cdefn_t rsp_at_word =     { indvarword,    "rsp@",    &rsp0_word,    &rsp }; //@W
-static cdefn_t rsp_pling_word =  { sp_pling_cb,   "rsp!",    &rsp_at_word,  NULL }; //@W
-static cdefn_t sp0_word =        { sysvarword,    "sp0",     &rsp_pling_word, dstack }; //@W
-static cdefn_t sp_at_word =      { indvarword,    "sp@",     &sp0_word,     &dsp }; //@W
-static cdefn_t sp_pling_word =   { sp_pling_cb,   "sp!",     &sp_at_word,   NULL }; //@W
-static cdefn_t stderr_word =     { indvarword,    "_stderr", &sp_pling_word, &stderr, }; //@W
-static cdefn_t stdin_word =      { indvarword,    "_stdin",  &stderr_word,  &stdin, }; //@W
-static cdefn_t stdout_word =     { indvarword,    "_stdout", &stdin_word,   &stdout, }; //@W
-static cdefn_t sub_word =        { sub_cb,        "-",       &stdout_word,  NULL }; //@W
-static cdefn_t tib_h_word =      { sysvarword,    "tib#",    &sub_word,     &tib_h }; //@W
-static cdefn_t tib_word =        { sysvarword,    "tib",     &tib_h_word,   tib }; //@W
-static cdefn_t type_word =       { codeword,      "emit",    &tib_word,     type_ops }; //@W
-static cdefn_t zero_word =       { sysvarword,    "0",       &type_word,    (void*)0, }; //@W
+static cdefn_t rsp0_word =       { rvarword,      "rsp0",    &quit_word,    rstack }; //@W
+static cdefn_t rsp_at_word =     { rivarword,     "rsp@",    &rsp0_word,    &rsp }; //@W
+static cdefn_t rsp_pling_word =  { wivarword,     "rsp!",    &rsp_at_word,  &rsp }; //@W
+static cdefn_t sp0_word =        { rvarword,      "sp0",     &rsp_pling_word, dstack }; //@W
+static cdefn_t sp_at_word =      { rivarword,     "sp@",     &sp0_word,     &dsp }; //@W
+static cdefn_t sp_pling_word =   { wivarword,     "sp!",     &sp_at_word,   &dsp }; //@W
+static cdefn_t sub_word =        { sub_cb,        "-",       &sp_pling_word, NULL }; //@W
+static cdefn_t tib_h_word =      { rvarword,      "tib#",    &sub_word,     &tib_h }; //@W
+static cdefn_t tib_word =        { rvarword,      "tib",     &tib_h_word,   tib }; //@W
+static cdefn_t type_word =       { codeword,      "type",    &tib_word,     type_ops }; //@W
+static cdefn_t zero_word =       { rvarword,      "0",       &type_word,    (void*)0, }; //@W
 
 static cdefn_t* latest = &zero_word; //@E
 
@@ -409,6 +396,7 @@ int main(int argc, const char* argv[])
        for (;;)
        {
                const struct definition* w = (void*) *pc++;
+               //printf("[%s]\n", w->name);
                w->code(w);
        }
 }