Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1%option prefix="expr_"
2%option reentrant
3%option bison-bridge
4
5%{
6#include <linux/compiler.h>
7#include "expr.h"
8#include "expr-bison.h"
9
10char *expr_get_text(yyscan_t yyscanner);
11YYSTYPE *expr_get_lval(yyscan_t yyscanner);
12
13static int __value(YYSTYPE *yylval, char *str, int base, int token)
14{
15 u64 num;
16
17 errno = 0;
18 num = strtoull(str, NULL, base);
19 if (errno)
20 return EXPR_ERROR;
21
22 yylval->num = num;
23 return token;
24}
25
26static int value(yyscan_t scanner, int base)
27{
28 YYSTYPE *yylval = expr_get_lval(scanner);
29 char *text = expr_get_text(scanner);
30
31 return __value(yylval, text, base, NUMBER);
32}
33
34/*
35 * Allow @ instead of / to be able to specify pmu/event/ without
36 * conflicts with normal division.
37 */
38static char *normalize(char *str)
39{
40 char *ret = str;
41 char *dst = str;
42
43 while (*str) {
44 if (*str == '@')
45 *dst++ = '/';
46 else if (*str == '\\')
47 *dst++ = *++str;
48 else
49 *dst++ = *str;
50 str++;
51 }
52
53 *dst = 0x0;
54 return ret;
55}
56
57static int str(yyscan_t scanner, int token)
58{
59 YYSTYPE *yylval = expr_get_lval(scanner);
60 char *text = expr_get_text(scanner);
61
62 yylval->str = normalize(strdup(text));
63 if (!yylval->str)
64 return EXPR_ERROR;
65
66 yylval->str = normalize(yylval->str);
67 return token;
68}
69%}
70
71number [0-9]+
72
73sch [-,=]
74spec \\{sch}
75sym [0-9a-zA-Z_\.:@]+
76symbol {spec}*{sym}*{spec}*{sym}*
77
78%%
79 {
80 int start_token;
81
82 start_token = expr_get_extra(yyscanner);
83
84 if (start_token) {
85 expr_set_extra(NULL, yyscanner);
86 return start_token;
87 }
88 }
89
90max { return MAX; }
91min { return MIN; }
92if { return IF; }
93else { return ELSE; }
94#smt_on { return SMT_ON; }
95{number} { return value(yyscanner, 10); }
96{symbol} { return str(yyscanner, ID); }
97"|" { return '|'; }
98"^" { return '^'; }
99"&" { return '&'; }
100"-" { return '-'; }
101"+" { return '+'; }
102"*" { return '*'; }
103"/" { return '/'; }
104"%" { return '%'; }
105"(" { return '('; }
106")" { return ')'; }
107"," { return ','; }
108. { }
109%%
110
111int expr_wrap(void *scanner __maybe_unused)
112{
113 return 1;
114}