1 %{
2 /*
3 * A scanner for EMP-style numeric ranges
4 */
5
6 /* LCOV_EXCL_START */
7
8 /* No reason to constrain amount of data slurped */
9 #define YY_READ_BUF_SIZE 16777216
10
11 /* Avoid exit() on fatal scanner errors (a bit ugly -- see yy_fatal_error) */
12 #undef fprintf
13 #define fprintf(file, fmt, msg) fprintf_to_ereport(fmt, msg)
14
15 static void
fprintf_to_ereport(const char * fmt,const char * msg)16 fprintf_to_ereport(const char *fmt, const char *msg)
17 {
18 ereport(ERROR, (errmsg_internal("%s", msg)));
19 }
20
21 /* Handles to the buffer that the lexer uses internally */
22 static YY_BUFFER_STATE scanbufhandle;
23 static char *scanbuf;
24 static int scanbuflen;
25 %}
26
27 %option 8bit
28 %option never-interactive
29 %option nodefault
30 %option noinput
31 %option nounput
32 %option noyywrap
33 %option warn
34 %option prefix="seg_yy"
35
36
37 range (\.\.)(\.)?
38 plumin (\'\+\-\')|(\(\+\-)\)
39 integer [+-]?[0-9]+
40 real [+-]?[0-9]+\.[0-9]+
41 float ({integer}|{real})([eE]{integer})?
42
43 %%
44
45 {range} yylval.text = yytext; return RANGE;
46 {plumin} yylval.text = yytext; return PLUMIN;
47 {float} yylval.text = yytext; return SEGFLOAT;
48 \< yylval.text = "<"; return EXTENSION;
49 \> yylval.text = ">"; return EXTENSION;
50 \~ yylval.text = "~"; return EXTENSION;
51 [ \t\n\r\f]+ /* discard spaces */
52 . return yytext[0]; /* alert parser of the garbage */
53
54 %%
55
56 /* LCOV_EXCL_STOP */
57
58 void
59 yyerror(SEG *result, const char *message)
60 {
61 if (*yytext == YY_END_OF_BUFFER_CHAR)
62 {
63 ereport(ERROR,
64 (errcode(ERRCODE_SYNTAX_ERROR),
65 errmsg("bad seg representation"),
66 /* translator: %s is typically "syntax error" */
67 errdetail("%s at end of input", message)));
68 }
69 else
70 {
71 ereport(ERROR,
72 (errcode(ERRCODE_SYNTAX_ERROR),
73 errmsg("bad seg representation"),
74 /* translator: first %s is typically "syntax error" */
75 errdetail("%s at or near \"%s\"", message, yytext)));
76 }
77 }
78
79
80 /*
81 * Called before any actual parsing is done
82 */
83 void
84 seg_scanner_init(const char *str)
85 {
86 Size slen = strlen(str);
87
88 /*
89 * Might be left over after ereport()
90 */
91 if (YY_CURRENT_BUFFER)
92 yy_delete_buffer(YY_CURRENT_BUFFER);
93
94 /*
95 * Make a scan buffer with special termination needed by flex.
96 */
97 scanbuflen = slen;
98 scanbuf = palloc(slen + 2);
99 memcpy(scanbuf, str, slen);
100 scanbuf[slen] = scanbuf[slen + 1] = YY_END_OF_BUFFER_CHAR;
101 scanbufhandle = yy_scan_buffer(scanbuf, slen + 2);
102
103 BEGIN(INITIAL);
104 }
105
106
107 /*
108 * Called after parsing is done to clean up after seg_scanner_init()
109 */
110 void
111 seg_scanner_finish(void)
112 {
113 yy_delete_buffer(scanbufhandle);
114 pfree(scanbuf);
115 }
116