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/* Generated by re2c */
// re2c $INPUT -o $OUTPUT --loop-switch -i
#include <assert.h>
#include <stdio.h>
#include <string.h>
#define YYMAXFILL 1
#define SIZE 4096
typedef struct {
FILE *file;
char buf[SIZE + YYMAXFILL], *lim, *cur, *mar, *tok;
int eof;
} Input;
static int fill(Input *in, size_t need)
{
if (in->eof) {
return 1;
}
const size_t free = in->tok - in->buf;
if (free < need) {
return 2;
}
memmove(in->buf, in->tok, in->lim - in->tok);
in->lim -= free;
in->cur -= free;
in->mar -= free;
in->tok -= free;
in->lim += fread(in->lim, 1, free, in->file);
if (in->lim < in->buf + SIZE) {
in->eof = 1;
memset(in->lim, 0, YYMAXFILL);
in->lim += YYMAXFILL;
}
return 0;
}
static void init(Input *in, FILE *file)
{
in->file = file;
in->cur = in->mar = in->tok = in->lim = in->buf + SIZE;
in->eof = 0;
fill(in, 1);
}
static int lex(Input *in)
{
int count = 0;
loop:
in->tok = in->cur;
{
char yych;
unsigned int yystate = 0;
for (;;) {
switch (yystate) {
case 0:
if (in->lim <= in->cur) if (fill(in, 1) != 0) return -1;
yych = *in->cur;
++in->cur;
switch (yych) {
case 0x00:
yystate = 1;
continue;
case ' ':
yystate = 3;
continue;
case '\'':
yystate = 5;
continue;
default:
yystate = 2;
continue;
}
case 1: { return (in->lim - in->cur == YYMAXFILL - 1) ? count : -1; }
case 2: { return -1; }
case 3:
if (in->lim <= in->cur) if (fill(in, 1) != 0) return -1;
yych = *in->cur;
switch (yych) {
case ' ':
++in->cur;
yystate = 3;
continue;
default:
yystate = 4;
continue;
}
case 4: { goto loop; }
case 5:
if (in->lim <= in->cur) if (fill(in, 1) != 0) return -1;
yych = *in->cur;
++in->cur;
switch (yych) {
case '\'':
yystate = 6;
continue;
case '\\':
yystate = 7;
continue;
default:
yystate = 5;
continue;
}
case 6: { ++count; goto loop; }
case 7:
if (in->lim <= in->cur) if (fill(in, 1) != 0) return -1;
++in->cur;
yystate = 5;
continue;
}
}
}
}
int main()
{
const char *fname = "input";
const char str[] = "'qu\0tes' 'are' 'fine: \\'' ";
FILE *f;
Input in;
// prepare input file: a few times the size of the buffer,
// containing strings with zeroes and escaped quotes
f = fopen(fname, "w");
for (int i = 0; i < SIZE; ++i) {
fwrite(str, 1, sizeof(str) - 1, f);
}
fclose(f);
f = fopen(fname, "r");
init(&in, f);
assert(lex(&in) == SIZE * 3);
fclose(f);
remove(fname);
return 0;
}
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