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-rw-r--r--ChangeLog26
-rw-r--r--parser.l94
-rw-r--r--parser.y73
-rw-r--r--stream.c12
-rw-r--r--stream.h1
5 files changed, 141 insertions, 65 deletions
diff --git a/ChangeLog b/ChangeLog
index 36f9205d..bdb76184 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,31 @@
2011-10-26 Kaz Kylheku <kaz@kylheku.com>
+ Parse error handling improvements.
+
+ * parser.l (prepared_error_message): New static variable.
+ (yyerror): Emit and clear prepared error message.
+ (yyerrprepf): New static function.
+ (yybadtoken): Function moved into parser.y.
+ (grammar): For irrecoverable lexical errors, stash error message
+ with yyerrprepf and return the special error token ERRTOK to generate a
+ syntax error. I could find no other interface to the parser to make it
+ cleanly exit.
+
+ * parser.y (ERRTOK): New terminal symbol, does not appear anywhere
+ in the grammar.
+ (spec): Bail after 8 errors, recover to nearest newline, and
+ use yyerrok to clear error situation.
+ (YYEOF): Provided by Bison, conditionally defined for other yacc-s.
+ (yybadtoken): Function moved from parser.l. Checks for the next
+ token being YYEMPTY or YYEOF, and also handles ERRTOK.
+
+ * stream.c (vformat_to_string): New function.
+ (format): If stream is nil, format to string and return it.
+
+ * stream.h (vformat_to_string): Declared.
+
+2011-10-26 Kaz Kylheku <kaz@kylheku.com>
+
* match.c (v_cat): Bugfix: unterminated variable argument list.
* tests/001/query-3.txr: Updated to new cat syntax.
diff --git a/parser.l b/parser.l
index af450f95..08bdfbb3 100644
--- a/parser.l
+++ b/parser.l
@@ -68,9 +68,15 @@ int opt_arraydims = 1;
int errors;
+static val prepared_error_message;
+
void yyerror(const char *s)
{
yyerrorf(lit("~a"), string_utf8(s), nao);
+ if (prepared_error_message) {
+ yyerrorf(lit("~a"), prepared_error_message, nao);
+ prepared_error_message = nil;
+ }
}
void yyerrorf(val fmt, ...)
@@ -87,55 +93,14 @@ void yyerrorf(val fmt, ...)
errors++;
}
-void yybadtoken(int tok, val context)
+static void yyerrprepf(val fmt, ...)
{
- val problem = nil;
-
- switch (tok) {
- case SPACE: problem = lit("space"); break;
- case TEXT: problem = lit("text"); break;
- case IDENT: problem = lit("identifier"); break;
- case KEYWORD: problem = lit("keyword"); break;
- case METAVAR: problem = lit("metavar"); break;
- case ALL: problem = lit("\"all\""); break;
- case SOME: problem = lit("\"some\""); break;
- case NONE: problem = lit("\"none\""); break;
- case MAYBE: problem = lit("\"maybe\""); break;
- case CASES: problem = lit("\"cases\""); break;
- case CHOOSE: problem = lit("\"choose\""); break;
- case AND: problem = lit("\"and\""); break;
- case OR: problem = lit("\"or\""); break;
- case END: problem = lit("\"end\""); break;
- case COLLECT: problem = lit("\"collect\""); break;
- case UNTIL: problem = lit("\"until\""); break;
- case COLL: problem = lit("\"coll\""); break;
- case OUTPUT: problem = lit("\"output\""); break;
- case REPEAT: problem = lit("\"repeat\""); break;
- case REP: problem = lit("\"rep\""); break;
- case SINGLE: problem = lit("\"single\""); break;
- case FIRST: problem = lit("\"first\""); break;
- case LAST: problem = lit("\"last\""); break;
- case EMPTY: problem = lit("\"empty\""); break;
- case DEFINE: problem = lit("\"define\""); break;
- case TRY: problem = lit("\"try\""); break;
- case CATCH: problem = lit("\"catch\""); break;
- case FINALLY: problem = lit("\"finally\""); break;
- case NUMBER: problem = lit("\"number\""); break;
- case REGCHAR: problem = lit("regular expression character"); break;
- case LITCHAR: problem = lit("string literal character"); break;
- case METAPAR: problem = lit("@("); break;
+ if (opt_loglevel >= 1) {
+ va_list vl;
+ va_start (vl, fmt);
+ prepared_error_message = vformat_to_string(fmt, vl);
+ va_end (vl);
}
-
- if (problem != 0)
- if (context)
- yyerrorf(lit("misplaced ~a in ~a"), problem, context, nao);
- else
- yyerrorf(lit("unexpected ~a"), problem, nao);
- else
- if (context)
- yyerrorf(lit("unterminated ~a"), context, nao);
- else
- yyerrorf(lit("unexpected end of input"), nao);
}
static wchar_t char_esc(int letter)
@@ -444,14 +409,16 @@ UONLY {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
}
<SPECIAL,NESTED>{UANYN} {
- yyerrorf(lit("bad character in directive: '~a'"),
- string_utf8(yytext), nao);
+ yyerrprepf(lit("bad character in directive: '~a'"),
+ string_utf8(yytext), nao);
+ return ERRTOK;
}
<SPECIAL,NESTED>. {
- yyerrorf(lit("non-UTF-8 byte in directive: "
- "'\\x~02x'"),
+ yyerrprepf(lit("non-UTF-8 byte in directive: "
+ "'\\x~02x'"),
num((unsigned char) yytext[0]), nao);
+ return ERRTOK;
}
<REGEX>[/] {
@@ -476,7 +443,8 @@ UONLY {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
<REGEX>\n {
lineno++;
- yyerror("newline in regex");
+ yyerrprepf(lit("newline in regex"), nao);
+ return ERRTOK;
}
<REGEX>[.*?+~&%] {
@@ -508,8 +476,9 @@ UONLY {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
}
<REGEX>. {
- yyerrorf(lit("non-UTF-8 byte in regex: '\\x~02x'"),
- num((unsigned char) yytext[0]), nao);
+ yyerrprepf(lit("non-UTF-8 byte in regex: '\\x~02x'"),
+ num((unsigned char) yytext[0]), nao);
+ return ERRTOK;
}
<INITIAL>[ ]+ {
@@ -574,24 +543,24 @@ UONLY {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
return LITCHAR;
}
<STRLIT>\n {
- yyerror("newline in string literal");
+ yyerrprepf(lit("newline in string literal"), nao);
lineno++;
yylval.chr = yytext[0];
- return LITCHAR;
+ return ERRTOK;
}
<CHRLIT>\n {
- yyerror("newline in character literal");
+ yyerrprepf(lit("newline in character literal"), nao);
lineno++;
yylval.chr = yytext[0];
- return LITCHAR;
+ return ERRTOK;
}
<QSILIT>\n {
- yyerror("newline in string quasiliteral");
+ yyerrprepf(lit("newline in string quasiliteral"), nao);
lineno++;
yylval.chr = yytext[0];
- return LITCHAR;
+ return ERRTOK;
}
<QSILIT>@ {
@@ -606,8 +575,9 @@ UONLY {U2}{U}|{U3}{U}{U}|{U4}{U}{U}{U}
}
<STRLIT,CHRLIT,QSILIT>. {
- yyerrorf(lit("non-UTF-8 byte in regex: '\\x~02x'"),
- num((unsigned char) yytext[0]), nao);
+ yyerrprepf(lit("non-UTF-8 byte in regex: '\\x~02x'"),
+ num((unsigned char) yytext[0]), nao);
+ return ERRTOK;
}
%%
diff --git a/parser.y b/parser.y
index 004211aa..1437e982 100644
--- a/parser.y
+++ b/parser.y
@@ -63,6 +63,7 @@ static val parsed_spec;
%token <lexeme> AND OR END COLLECT
%token <lexeme> UNTIL COLL OUTPUT REPEAT REP SINGLE FIRST LAST EMPTY DEFINE
%token <lexeme> TRY CATCH FINALLY
+%token <lexeme> ERRTOK
%token <num> NUMBER
@@ -99,8 +100,12 @@ static val parsed_spec;
spec : clauses { parsed_spec = $1; }
| /* empty */ { parsed_spec = nil; }
- | error { parsed_spec = nil;
+ | error '\n' { parsed_spec = nil;
+ if (errors >= 8)
+ YYABORT;
+ yyerrok;
yybadtoken(yychar, nil); }
+
;
clauses : clause { $$ = cons($1, nil); }
@@ -778,3 +783,69 @@ val get_spec(void)
{
return parsed_spec;
}
+
+#ifndef YYEOF
+#define YYEOF YYEMPTY
+#endif
+
+void yybadtoken(int tok, val context)
+{
+ val problem = nil;
+
+ switch (tok) {
+ case ERRTOK:
+ return;
+ case SPACE: problem = lit("space"); break;
+ case TEXT: problem = lit("text"); break;
+ case IDENT: problem = lit("identifier"); break;
+ case KEYWORD: problem = lit("keyword"); break;
+ case METAVAR: problem = lit("metavar"); break;
+ case ALL: problem = lit("\"all\""); break;
+ case SOME: problem = lit("\"some\""); break;
+ case NONE: problem = lit("\"none\""); break;
+ case MAYBE: problem = lit("\"maybe\""); break;
+ case CASES: problem = lit("\"cases\""); break;
+ case CHOOSE: problem = lit("\"choose\""); break;
+ case AND: problem = lit("\"and\""); break;
+ case OR: problem = lit("\"or\""); break;
+ case END: problem = lit("\"end\""); break;
+ case COLLECT: problem = lit("\"collect\""); break;
+ case UNTIL: problem = lit("\"until\""); break;
+ case COLL: problem = lit("\"coll\""); break;
+ case OUTPUT: problem = lit("\"output\""); break;
+ case REPEAT: problem = lit("\"repeat\""); break;
+ case REP: problem = lit("\"rep\""); break;
+ case SINGLE: problem = lit("\"single\""); break;
+ case FIRST: problem = lit("\"first\""); break;
+ case LAST: problem = lit("\"last\""); break;
+ case EMPTY: problem = lit("\"empty\""); break;
+ case DEFINE: problem = lit("\"define\""); break;
+ case TRY: problem = lit("\"try\""); break;
+ case CATCH: problem = lit("\"catch\""); break;
+ case FINALLY: problem = lit("\"finally\""); break;
+ case NUMBER: problem = lit("\"number\""); break;
+ case REGCHAR: problem = lit("regular expression character"); break;
+ case LITCHAR: problem = lit("string literal character"); break;
+ case METAPAR: problem = lit("@("); break;
+ }
+
+ if (problem != 0)
+ if (context)
+ yyerrorf(lit("misplaced ~a in ~a"), problem, context, nao);
+ else
+ yyerrorf(lit("unexpected ~a"), problem, nao);
+ else
+ if (context)
+ if (tok == YYEOF || tok == YYEMPTY)
+ yyerrorf(lit("unterminated ~a"), context, nao);
+ else
+ yyerrorf(lit("misplaced ~s in ~a"), chr(tok), context, nao);
+ else
+ if (tok == YYEOF)
+ yyerrorf(lit("unexpected end of input"), nao);
+ else if (tok == YYEMPTY)
+ return;
+ else
+ yyerrorf(lit("unexpected ~s"), chr(tok), nao);
+}
+
diff --git a/stream.c b/stream.c
index bb9641df..6062d91e 100644
--- a/stream.c
+++ b/stream.c
@@ -998,8 +998,16 @@ toobig:
internal_error("ridiculous precision or field width in format");
}
+val vformat_to_string(val fmtstr, va_list vl)
+{
+ val stream = make_string_output_stream();
+ (void) vformat(stream, fmtstr, vl);
+ return get_string_from_stream(stream);
+}
+
val format(val stream, val str, ...)
{
+ val st = or2(stream, make_string_output_stream());
type_check (stream, COBJ);
type_assert (stream->co.cls == stream_s, (lit("~a is not a stream"),
stream, nao));
@@ -1008,9 +1016,9 @@ val format(val stream, val str, ...)
va_list vl;
val ret;
va_start (vl, str);
- ret = vformat(stream, str, vl);
+ ret = vformat(st, str, vl);
va_end (vl);
- return ret;
+ return (stream) ? ret : get_string_from_stream(st);
}
}
diff --git a/stream.h b/stream.h
index 9e703378..161be5da 100644
--- a/stream.h
+++ b/stream.h
@@ -40,6 +40,7 @@ val get_line(val);
val get_char(val);
val get_byte(val);
val vformat(val stream, val string, va_list);
+val vformat_to_string(val string, va_list);
val format(val stream, val string, ...);
val put_string(val stream, val string);
val put_line(val stream, val string);
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-10 16:07:57 +0000