1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
// re2c $INPUT -o $OUTPUT -f --loop-switch -i
#include <assert.h>
#include <stdio.h>
#include <string.h>
#define DEBUG 1
#define LOG(...) if (DEBUG) fprintf(stderr, __VA_ARGS__);
#define BUFSIZE 10
typedef struct {
FILE *file;
char buf[BUFSIZE + 1], *lim, *cur, *mar, *tok;
unsigned yyaccept;
int state;
} Input;
static void init(Input *in, FILE *f)
{
in->file = f;
in->cur = in->mar = in->tok = in->lim = in->buf + BUFSIZE;
in->lim[0] = 0; // append sentinel symbol
in->yyaccept = 0;
in->state = -1;
}
typedef enum {END, READY, WAITING, BAD_PACKET, BIG_PACKET} Status;
static Status fill(Input *in)
{
const size_t shift = in->tok - in->buf;
const size_t free = BUFSIZE - (in->lim - in->tok);
if (free < 1) return BIG_PACKET;
memmove(in->buf, in->tok, BUFSIZE - shift);
in->lim -= shift;
in->cur -= shift;
in->mar -= shift;
in->tok -= shift;
const size_t read = fread(in->lim, 1, free, in->file);
in->lim += read;
in->lim[0] = 0; // append sentinel symbol
return READY;
}
static Status lex(Input *in, unsigned int *recv)
{
char yych;
loop:
/*!re2c
re2c:eof = 0;
re2c:api:style = free-form;
re2c:define:YYCTYPE = "char";
re2c:define:YYCURSOR = "in->cur";
re2c:define:YYMARKER = "in->mar";
re2c:define:YYLIMIT = "in->lim";
re2c:define:YYGETSTATE = "in->state";
re2c:define:YYSETSTATE = "in->state = @@;";
re2c:define:YYFILL = "return WAITING;";
packet = [a-z]+[;];
* { return BAD_PACKET; }
$ { return END; }
packet { *recv = *recv + 1; in->tok = in->cur; goto loop; }
*/
}
void test(const char **packets, Status status)
{
const char *fname = "pipe";
FILE *fw = fopen(fname, "w");
FILE *fr = fopen(fname, "r");
setvbuf(fw, NULL, _IONBF, 0);
setvbuf(fr, NULL, _IONBF, 0);
Input in;
init(&in, fr);
Status st;
unsigned int send = 0, recv = 0;
for (;;) {
st = lex(&in, &recv);
if (st == END) {
LOG("done: got %u packets\n", recv);
break;
} else if (st == WAITING) {
LOG("waiting...\n");
if (*packets) {
LOG("sent packet %u\n", send);
fprintf(fw, "%s", *packets++);
++send;
}
st = fill(&in);
LOG("queue: '%s'\n", in.buf);
if (st == BIG_PACKET) {
LOG("error: packet too big\n");
break;
}
assert(st == READY);
} else {
assert(st == BAD_PACKET);
LOG("error: ill-formed packet\n");
break;
}
}
LOG("\n");
assert(st == status);
if (st == END) assert(recv == send);
fclose(fw);
fclose(fr);
remove(fname);
}
int main()
{
const char *packets1[] = {0};
const char *packets2[] = {"zero;", "one;", "two;", "three;", "four;", 0};
const char *packets3[] = {"zer0;", 0};
const char *packets4[] = {"goooooooooogle;", 0};
test(packets1, END);
test(packets2, END);
test(packets3, BAD_PACKET);
test(packets4, BIG_PACKET);
return 0;
}
|
