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/* Generated by re2d */
#line 1 "codegen/d/02_storable_state_with_conditions.re"
// re2d $INPUT -o $OUTPUT -fc --loop-switch
module main;
import core.stdc.stdio;
import core.stdc.string;
// Use a small buffer to cover the case when a lexeme doesn't fit.
// In real world use a larger buffer.
enum BUFSIZE = 10;
#line 14 "codegen/d/02_storable_state_with_conditions.d"
enum YYCond {
yycINIT = 0,
yycSPACES = 6,
yycNUMBER = 11,
yycWORD = 16
};
#line 11 "codegen/d/02_storable_state_with_conditions.re"
struct State {
FILE* file;
char[BUFSIZE + 1] buf;
char* lim, cur, mar, tok;
int state;
};
enum Status {END, READY, WAITING, BAD_PACKET, BIG_PACKET};
private Status fill(ref State st) {
const size_t shift = st.tok - cast(char*)st.buf;
const size_t used = st.lim - st.tok;
const size_t free = BUFSIZE - used;
// Error: no space. In real life can reallocate a larger buffer.
if (free < 1) return Status.BIG_PACKET;
// Shift buffer contents (discard already processed data).
memmove(cast(void*)st.buf, st.tok, used);
st.lim -= shift;
st.cur -= shift;
st.mar -= shift;
st.tok -= shift;
// Fill free space at the end of buffer with new data.
const size_t read = fread(st.lim, 1, free, st.file);
st.lim += read;
st.lim[0] = 0; // append sentinel symbol
return Status.READY;
}
private Status lex(ref State st, uint* nc, uint* wc) {
char yych;
/* !getstate:re2c*/
lex:
for (;;) {
st.tok = st.cur;
#line 64 "codegen/d/02_storable_state_with_conditions.d"
{
int yystate = st.state;
yyl: while (true) {
switch (yystate) {
case -1: .. case 0:
yych = *st.cur;
switch (yych) {
case '\t':
case ' ':
st.cur += 1;
yystate = 2;
continue yyl;
case '0': .. case '9':
st.cur += 1;
yystate = 3;
continue yyl;
case 'a': .. case 'z':
st.cur += 1;
yystate = 4;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 21;
return Status.WAITING;
}
st.cur += 1;
yystate = 1;
continue yyl;
}
case 1:
st.state = YYCond.yycINIT;
#line 70 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.BAD_PACKET; }
#line 98 "codegen/d/02_storable_state_with_conditions.d"
case 2:
st.cur += -1;
st.state = YYCond.yycSPACES;
yystate = YYCond.yycSPACES;
continue yyl;
case 3:
st.cur += -1;
st.state = YYCond.yycNUMBER;
yystate = YYCond.yycNUMBER;
continue yyl;
case 4:
st.cur += -1;
st.state = YYCond.yycWORD;
yystate = YYCond.yycWORD;
continue yyl;
case 5:
st.state = YYCond.yycINIT;
#line 71 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.END; }
#line 118 "codegen/d/02_storable_state_with_conditions.d"
case 6:
yych = *st.cur;
switch (yych) {
case '\t':
case ' ':
st.cur += 1;
yystate = 8;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 22;
return Status.WAITING;
}
st.cur += 1;
yystate = 7;
continue yyl;
}
case 7:
st.state = YYCond.yycSPACES;
#line 70 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.BAD_PACKET; }
#line 140 "codegen/d/02_storable_state_with_conditions.d"
case 8:
yych = *st.cur;
switch (yych) {
case '\t':
case ' ':
st.cur += 1;
yystate = 8;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 23;
return Status.WAITING;
}
yystate = 9;
continue yyl;
}
case 9:
st.state = YYCond.yycINIT;
#line 77 "codegen/d/02_storable_state_with_conditions.re"
{ continue lex; }
#line 161 "codegen/d/02_storable_state_with_conditions.d"
case 10:
st.state = YYCond.yycSPACES;
#line 71 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.END; }
#line 166 "codegen/d/02_storable_state_with_conditions.d"
case 11:
yych = *st.cur;
switch (yych) {
case '0': .. case '9':
st.cur += 1;
yystate = 13;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 24;
return Status.WAITING;
}
st.cur += 1;
yystate = 12;
continue yyl;
}
case 12:
st.state = YYCond.yycNUMBER;
#line 70 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.BAD_PACKET; }
#line 187 "codegen/d/02_storable_state_with_conditions.d"
case 13:
yych = *st.cur;
switch (yych) {
case '0': .. case '9':
st.cur += 1;
yystate = 13;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 25;
return Status.WAITING;
}
yystate = 14;
continue yyl;
}
case 14:
st.state = YYCond.yycSPACES;
#line 79 "codegen/d/02_storable_state_with_conditions.re"
{ *nc += 1; continue lex; }
#line 207 "codegen/d/02_storable_state_with_conditions.d"
case 15:
st.state = YYCond.yycNUMBER;
#line 71 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.END; }
#line 212 "codegen/d/02_storable_state_with_conditions.d"
case 16:
yych = *st.cur;
switch (yych) {
case 'a': .. case 'z':
st.cur += 1;
yystate = 18;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 26;
return Status.WAITING;
}
st.cur += 1;
yystate = 17;
continue yyl;
}
case 17:
st.state = YYCond.yycWORD;
#line 70 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.BAD_PACKET; }
#line 233 "codegen/d/02_storable_state_with_conditions.d"
case 18:
yych = *st.cur;
switch (yych) {
case 'a': .. case 'z':
st.cur += 1;
yystate = 18;
continue yyl;
default:
if (st.cur >= st.lim) {
st.state = 27;
return Status.WAITING;
}
yystate = 19;
continue yyl;
}
case 19:
st.state = YYCond.yycSPACES;
#line 80 "codegen/d/02_storable_state_with_conditions.re"
{ *wc += 1; continue lex; }
#line 253 "codegen/d/02_storable_state_with_conditions.d"
case 20:
st.state = YYCond.yycWORD;
#line 71 "codegen/d/02_storable_state_with_conditions.re"
{ return Status.END; }
#line 258 "codegen/d/02_storable_state_with_conditions.d"
case 21:
if (st.cur >= st.lim) {
yystate = 5;
continue yyl;
}
yystate = 0;
continue yyl;
case 22:
if (st.cur >= st.lim) {
yystate = 10;
continue yyl;
}
yystate = 6;
continue yyl;
case 23:
if (st.cur >= st.lim) {
yystate = 9;
continue yyl;
}
yystate = 8;
continue yyl;
case 24:
if (st.cur >= st.lim) {
yystate = 15;
continue yyl;
}
yystate = 11;
continue yyl;
case 25:
if (st.cur >= st.lim) {
yystate = 14;
continue yyl;
}
yystate = 13;
continue yyl;
case 26:
if (st.cur >= st.lim) {
yystate = 20;
continue yyl;
}
yystate = 16;
continue yyl;
case 27:
if (st.cur >= st.lim) {
yystate = 19;
continue yyl;
}
yystate = 18;
continue yyl;
default: assert(false);
}
}
}
#line 81 "codegen/d/02_storable_state_with_conditions.re"
}
assert(0); // unreachable
}
private void test(string[] packets, Status expect, int numbers, int words) {
// Create a "socket" (open the same file for reading and writing).
const(char*) fname = "pipe";
FILE* fw = fopen(fname, "w");
FILE* fr = fopen(fname, "r");
setvbuf(fw, null, _IONBF, 0);
setvbuf(fr, null, _IONBF, 0);
// Initialize lexer state: `state` value is -1, all pointers are at the end
// of buffer.
State st;
st.file = fr;
st.cur = st.mar = st.tok = st.lim = cast(char*)st.buf + BUFSIZE;
// Sentinel (at YYLIMIT pointer) is set to zero, which triggers YYFILL.
st.lim[0] = 0;
st.state = -1;
// Main loop. The buffer contains incomplete data which appears packet by
// packet. When the lexer needs more input it saves its internal state and
// returns to the caller which should provide more input and resume lexing.
Status status;
uint send = 0, nc = 0, wc = 0;
for (;;) {
status = lex(st, &nc, &wc);
if (status == Status.END) {
debug{printf("done: got %u numbers and %u words\n", nc, wc);}
break;
} else if (status == Status.WAITING) {
debug{printf("waiting...\n");}
if (send < packets.length) {
debug{printf("sent packet %u\n", send);}
fprintf(fw, "%s", cast(char*)packets[send]);
++send;
}
status = fill(st);
debug{printf("queue: '%s'\n", cast(char*)st.buf);}
if (status == Status.BIG_PACKET) {
debug{printf("error: packet too big\n");}
break;
}
assert(status == Status.READY);
} else {
assert(status == Status.BAD_PACKET);
debug{printf("error: ill-formed packet\n");}
break;
}
}
// Check results.
assert(status == expect);
if (status == Status.END) assert(nc == numbers && wc == words);
// Cleanup: remove input file.
fclose(fw);
fclose(fr);
remove(fname);
}
void main() {
string[] packets1 = [];
string[] packets2 = [" zero one", " ", "123", "4 tw", "o 456789"];
string[] packets3 = ["zer0"];
string[] packets4 = ["looooooooooong;"];
test(packets1, Status.END, 0, 0);
test(packets2, Status.END, 2, 3);
test(packets3, Status.BAD_PACKET, -1, -1);
test(packets4, Status.BIG_PACKET, -1, -1);
}
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