X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/b9f1d9a47a49c40e8f0a5006b492daba53f25b20..7439c5c0f94940884e998c06b910476c6f6145b5:/src/scan-code.l
diff --git a/src/scan-code.l b/src/scan-code.l
index 4c91fd1a..56cd7825 100644
--- a/src/scan-code.l
+++ b/src/scan-code.l
@@ -17,7 +17,7 @@
You should have received a copy of the GNU General Public License
along with this program. If not, see . */
-%option debug nodefault nounput noyywrap never-interactive
+%option debug nodefault noinput nounput noyywrap never-interactive
%option prefix="code_" outfile="lex.yy.c"
%{
@@ -32,12 +32,14 @@
#include
#include
#include
-#include
-#include
#include
#include
#include
+#include
+#include
+#include
+
/* The current calling start condition: SC_RULE_ACTION or
SC_SYMBOL_ACTION. */
# define YY_DECL static char *code_lex (code_props *self, int sc_context)
@@ -49,7 +51,7 @@ static void handle_action_dollar (symbol_list *rule, char *cp,
location dollar_loc);
static void handle_action_at (symbol_list *rule, char *cp, location at_loc);
-/* A string to be pushed to obstack after dollar/at has been handled */
+/* A string to be pushed to obstack after dollar/at has been handled. */
static char *ref_tail_fields;
static location the_location;
@@ -81,7 +83,8 @@ tag [^\0\n>]+
splice (\\[ \f\t\v]*\n)*
/* C style identifier. Must start with letter. Will be used for
- named symbol references. */
+ named symbol references. Shall be kept synchronized with
+ scan-gram.l "letter" and "id". */
letter [-.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_]
id {letter}({letter}|[0-9])*
ref -?[0-9]+|{id}|"["{id}"]"|"$"
@@ -181,7 +184,7 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$"
"$"("<"{tag}">")?{ref} {
ref_tail_fields = 0;
handle_action_dollar (self->rule, yytext, *loc);
- if (ref_tail_fields != NULL) {
+ if (ref_tail_fields) {
obstack_sgrow (&obstack_for_string, ref_tail_fields);
}
need_semicolon = true;
@@ -189,7 +192,7 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$"
"@"{ref} {
ref_tail_fields = 0;
handle_action_at (self->rule, yytext, *loc);
- if (ref_tail_fields != NULL) {
+ if (ref_tail_fields) {
obstack_sgrow (&obstack_for_string, ref_tail_fields);
}
need_semicolon = true;
@@ -285,60 +288,57 @@ ref -?[0-9]+|{id}|"["{id}"]"|"$"
%%
-
-static inline bool
-symbol_list_null(symbol_list *l)
-{
- if (l && !(l->content_type == SYMLIST_SYMBOL && l->content.sym == NULL))
- return false;
- else
- return true;
-}
-
static inline bool
-is_dot_or_dash(char ch)
+is_dot_or_dash (char ch)
{
return ch == '.' || ch == '-';
}
static inline bool
-is_digit(char ch)
+contains_dot_or_dash (const char* p)
{
- return '0' <= ch && ch <= '9';
+ for (; *p; ++p)
+ if (is_dot_or_dash (*p))
+ return true;
+ return false;
}
-static inline bool
-contains_dot_or_dash(const char* str)
-{
- return strpbrk(str, ".-") != NULL;
-}
-
-#define VARIANT_HIDDEN (1 << 0)
-#define VARIANT_BAD_BRACKETING (1 << 1)
-#define VARIANT_NOT_VISIBLE_FROM_MIDRULE (1 << 2)
-
+/* Defines a variant of a symbolic name resolution. */
typedef struct
{
/* Index in symbol list. */
- long int ind;
+ unsigned symbol_index;
/* Matched symbol id and loc. */
uniqstr id;
location loc;
- /* Hidding named reference. */
+ /* Hiding named reference. */
named_ref* hidden_by;
- /* Error flags. */
+ /* Error flags. May contain zero (no errors) or
+ a combination of VARIANT_* values. */
unsigned err;
} variant;
+/* Set when the variant refers to a symbol hidden
+ by an explicit symbol reference. */
+#define VARIANT_HIDDEN (1 << 0)
+
+/* Set when the variant refers to a symbol containing
+ dots or dashes. Will require explicit bracketing. */
+#define VARIANT_BAD_BRACKETING (1 << 1)
+
+/* Set when the variant refers to a symbol which is
+ not visible from current midrule. */
+#define VARIANT_NOT_VISIBLE_FROM_MIDRULE (1 << 2)
+
static variant *variant_table = 0;
static unsigned variant_table_size = 0;
static unsigned variant_count = 0;
static variant *
-variant_table_grow()
+variant_table_grow (void)
{
++variant_count;
if (variant_count > variant_table_size)
@@ -351,17 +351,22 @@ variant_table_grow()
return &variant_table[variant_count - 1];
}
+static void
+variant_table_free (void)
+{
+ free (variant_table);
+ variant_table = 0;
+ variant_table_size = variant_count = 0;
+}
+
static char *
-find_prefix_end(const char *prefix, char *begin, char *end)
+find_prefix_end (const char *prefix, char *begin, char *end)
{
char *ptr = begin;
- while (*prefix && ptr != end)
- {
- if (*prefix != *ptr)
- return 0;
- ++prefix, ++ptr;
- }
+ for (; *prefix && ptr != end; ++prefix, ++ptr)
+ if (*prefix != *ptr)
+ return 0;
if (*prefix)
return 0;
@@ -370,20 +375,20 @@ find_prefix_end(const char *prefix, char *begin, char *end)
}
static variant *
-variant_add(uniqstr id, location loc, long int ind,
- char *cp, char *cp_end, bool exact_mode)
+variant_add (uniqstr id, location id_loc, unsigned symbol_index,
+ char *cp, char *cp_end, bool explicit_bracketing)
{
char *prefix_end;
- prefix_end = find_prefix_end(id, cp, cp_end);
+ prefix_end = find_prefix_end (id, cp, cp_end);
if (prefix_end &&
(prefix_end == cp_end ||
- (!exact_mode && is_dot_or_dash(*prefix_end))))
+ (!explicit_bracketing && is_dot_or_dash (*prefix_end))))
{
- variant *r = variant_table_grow();
- r->ind = ind;
+ variant *r = variant_table_grow ();
+ r->symbol_index = symbol_index;
r->id = id;
- r->loc = loc;
+ r->loc = id_loc;
r->hidden_by = NULL;
r->err = 0;
return r;
@@ -392,207 +397,266 @@ variant_add(uniqstr id, location loc, long int ind,
return NULL;
}
+static const char *
+get_at_spec(unsigned symbol_index)
+{
+ static char at_buf[20];
+ if (symbol_index == 0)
+ strcpy (at_buf, "$$");
+ else
+ snprintf (at_buf, sizeof at_buf, "$%u", symbol_index);
+ return at_buf;
+}
+
+static void
+show_sub_messages (const char* cp, bool explicit_bracketing,
+ int midrule_rhs_index, char dollar_or_at,
+ bool is_warning, unsigned indent)
+{
+ unsigned i;
+
+ for (i = 0; i < variant_count; ++i)
+ {
+ const variant *var = &variant_table[i];
+ const char *at_spec = get_at_spec (var->symbol_index);
+
+ if (var->err == 0)
+ {
+ if (is_warning)
+ warn_at_indent (var->loc, &indent, _("refers to: %c%s at %s"),
+ dollar_or_at, var->id, at_spec);
+ else
+ complain_at_indent (var->loc, &indent, _("refers to: %c%s at %s"),
+ dollar_or_at, var->id, at_spec);
+ }
+ else
+ {
+ static struct obstack msg_buf;
+ const char *tail = explicit_bracketing ? "" :
+ cp + strlen (var->id);
+ const char *id = var->hidden_by ? var->hidden_by->id :
+ var->id;
+ location id_loc = var->hidden_by ? var->hidden_by->loc :
+ var->loc;
+
+ /* Create the explanation message. */
+ obstack_init (&msg_buf);
+
+ obstack_fgrow1 (&msg_buf, _("possibly meant: %c"), dollar_or_at);
+ if (contains_dot_or_dash (id))
+ obstack_fgrow1 (&msg_buf, "[%s]", id);
+ else
+ obstack_sgrow (&msg_buf, id);
+ obstack_sgrow (&msg_buf, tail);
+
+ if (var->err & VARIANT_HIDDEN)
+ {
+ obstack_fgrow1 (&msg_buf, _(", hiding %c"), dollar_or_at);
+ if (contains_dot_or_dash (var->id))
+ obstack_fgrow1 (&msg_buf, "[%s]", var->id);
+ else
+ obstack_sgrow (&msg_buf, var->id);
+ obstack_sgrow (&msg_buf, tail);
+ }
+
+ obstack_fgrow1 (&msg_buf, _(" at %s"), at_spec);
+
+ if (var->err & VARIANT_NOT_VISIBLE_FROM_MIDRULE)
+ {
+ const char *format =
+ _(", cannot be accessed from mid-rule action at $%d");
+ obstack_fgrow1 (&msg_buf, format, midrule_rhs_index);
+ }
+
+ obstack_1grow (&msg_buf, '\0');
+ if (is_warning)
+ warn_at_indent (id_loc, &indent, "%s",
+ (char *) obstack_finish (&msg_buf));
+ else
+ complain_at_indent (id_loc, &indent, "%s",
+ (char *) obstack_finish (&msg_buf));
+ obstack_free (&msg_buf, 0);
+ }
+ }
+}
+
+/* Returned from "parse_ref" when the reference
+ is inappropriate. */
#define INVALID_REF (INT_MIN)
+
+/* Returned from "parse_ref" when the reference
+ points to LHS ($$) of the current rule or midrule. */
#define LHS_REF (INT_MIN + 1)
+/* Sub-messages indent. */
+#define SUB_INDENT (4)
+
+/* Parse named or positional reference. In case of positional
+ references, can return negative values for $-n "deep" stack
+ accesses. */
static long int
-parse_named_ref(char *cp, symbol_list *rule, int rule_length,
- int midrule_rhs_index, char *text, location loc,
- char dollar_or_at)
+parse_ref (char *cp, symbol_list *rule, int rule_length,
+ int midrule_rhs_index, char *text, location text_loc,
+ char dollar_or_at)
{
symbol_list *l;
char *cp_end;
- bool exact_mode;
- bool has_error;
- bool has_valid;
- long int ind, i;
- variant* variant;
- char* p;
+ bool explicit_bracketing;
+ unsigned i;
+ unsigned valid_variants = 0;
+ unsigned valid_variant_index = 0;
if ('$' == *cp)
return LHS_REF;
- if (is_digit (*cp) || (*cp == '-' && is_digit (* (cp + 1))))
+ if (c_isdigit (*cp) || (*cp == '-' && c_isdigit (* (cp + 1))))
{
long int num = strtol (cp, &cp, 10);
if (1 - INT_MAX + rule_length <= num && num <= rule_length)
return num;
else
{
- complain_at (loc, _("integer out of range: %s"), quote (text));
+ complain_at (text_loc, _("integer out of range: %s"),
+ quote (text));
return INVALID_REF;
}
}
if ('[' == *cp)
{
- exact_mode = true;
-
/* Ignore the brackets. */
- ++cp;
- for (p = cp; *p != ']'; ++p);
+ char *p;
+ for (p = ++cp; *p != ']'; ++p)
+ continue;
cp_end = p;
+
+ explicit_bracketing = true;
}
else
{
- exact_mode = false;
-
/* Take all characters of the name. */
+ char* p;
for (p = cp; *p; ++p)
- if (is_dot_or_dash(*p))
+ if (is_dot_or_dash (*p))
{
ref_tail_fields = p;
break;
}
- for (p = cp; *p; ++p);
+ for (p = cp; *p; ++p)
+ continue;
cp_end = p;
+
+ explicit_bracketing = false;
}
/* Add all relevant variants. */
- variant_count = 0;
- for (ind = 0, l = rule; !symbol_list_null(l); ++ind, l = l->next)
- {
- if (l->content_type != SYMLIST_SYMBOL)
- continue;
-
- variant = variant_add(l->content.sym->tag, l->sym_loc, ind,
- cp, cp_end, exact_mode);
-
- if (variant && l->named_ref)
- variant->hidden_by = l->named_ref;
-
- if (l->named_ref)
- variant_add(l->named_ref->id, l->named_ref->loc, ind,
- cp, cp_end, exact_mode);
- }
+ {
+ unsigned symbol_index;
+ variant_count = 0;
+ for (symbol_index = 0, l = rule; !symbol_list_null (l);
+ ++symbol_index, l = l->next)
+ {
+ variant *var;
+ if (l->content_type != SYMLIST_SYMBOL)
+ continue;
+
+ var = variant_add (l->content.sym->tag, l->sym_loc,
+ symbol_index, cp, cp_end, explicit_bracketing);
+ if (var && l->named_ref)
+ var->hidden_by = l->named_ref;
+
+ if (l->named_ref)
+ variant_add (l->named_ref->id, l->named_ref->loc,
+ symbol_index, cp, cp_end, explicit_bracketing);
+ }
+ }
/* Check errors. */
- has_error = false;
- has_valid = false;
for (i = 0; i < variant_count; ++i)
{
- variant = &variant_table[i];
- ind = variant->ind;
+ variant *var = &variant_table[i];
+ unsigned symbol_index = var->symbol_index;
/* Check visibility from mid-rule actions. */
- if (midrule_rhs_index != 0 &&
- (ind == 0 || ind > midrule_rhs_index))
- {
- variant->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE;
- has_error = true;
- }
+ if (midrule_rhs_index != 0
+ && (symbol_index == 0 || midrule_rhs_index < symbol_index))
+ var->err |= VARIANT_NOT_VISIBLE_FROM_MIDRULE;
/* Check correct bracketing. */
- if (!exact_mode && contains_dot_or_dash(variant->id))
- {
- variant->err |= VARIANT_BAD_BRACKETING;
- has_error = true;
- }
+ if (!explicit_bracketing && contains_dot_or_dash (var->id))
+ var->err |= VARIANT_BAD_BRACKETING;
/* Check using of hidden symbols. */
- if (variant->hidden_by != NULL)
- {
- variant->err |= VARIANT_HIDDEN;
- has_error = true;
- }
-
- if (!variant->err)
- has_valid = true;
+ if (var->hidden_by)
+ var->err |= VARIANT_HIDDEN;
+
+ if (!var->err)
+ {
+ valid_variant_index = i;
+ ++valid_variants;
+ }
}
- if (variant_count == 1 && has_valid)
- {
- /* The only "good" case is here. */
- ind = variant_table[0].ind;
- if (ind == midrule_rhs_index)
- return LHS_REF;
- else
- return ind;
- }
-
- /* Start complaining. */
-
- if (variant_count == 0)
- complain_at (loc, _("reference is invalid: %s, symbol not found"),
- quote (text));
- else if (variant_count > 1 && !has_error)
- complain_at (loc, _("reference is ambiguous: %s"),
- quote (text));
- else if (variant_count > 1 && has_valid && has_error)
- complain_at (loc, _("reference is misleading: %s"),
- quote (text));
- else
- complain_at (loc, _("reference is invalid: %s"),
- quote (text));
-
- for (i = 0; i < variant_count; ++i)
+ switch (valid_variants)
{
- static char at_buf[20];
-
- variant = &variant_table[i];
-
- if (variant->ind == 0)
- strcpy(at_buf, "$$");
- else
- snprintf(at_buf, sizeof(at_buf), "$%d", variant->ind);
-
- if (variant->err == 0)
- complain_at (variant->loc, _(" refers to: %c%s at %s"),
- dollar_or_at, variant->id, at_buf);
- else
- {
- static struct obstack msg_buf;
- const char *tail = "";
- const char *id;
- location loc;
-
- if (!exact_mode)
- tail = cp + strlen(variant->id);
-
- if (variant->hidden_by)
- {
- id = variant->hidden_by->id;
- loc = variant->hidden_by->loc;
- }
- else
- {
- id = variant->id;
- loc = variant->loc;
- }
-
- /* Create the explanation message. */
-
- obstack_init (&msg_buf);
-
- obstack_fgrow1 (&msg_buf, " possibly meant: %c", dollar_or_at);
- if (contains_dot_or_dash (id))
- obstack_fgrow1 (&msg_buf, "[%s]", id);
- else
- obstack_sgrow (&msg_buf, id);
- obstack_sgrow (&msg_buf, tail);
-
- if (variant->err & VARIANT_HIDDEN)
- {
- obstack_fgrow1 (&msg_buf, ", hiding %c", dollar_or_at);
- if (contains_dot_or_dash (variant->id))
- obstack_fgrow1 (&msg_buf, "[%s]", variant->id);
- else
- obstack_sgrow (&msg_buf, variant->id);
- obstack_sgrow (&msg_buf, tail);
- }
-
- obstack_fgrow1 (&msg_buf, " at %s", at_buf);
-
- if (variant->err & VARIANT_NOT_VISIBLE_FROM_MIDRULE)
- obstack_fgrow1 (&msg_buf, ", cannot be accessed from "
- "mid-rule action at $%d", midrule_rhs_index);
-
- obstack_1grow (&msg_buf, '\0');
- complain_at (loc, _("%s"), obstack_finish (&msg_buf));
- obstack_free (&msg_buf, 0);
- }
+ case 0:
+ {
+ unsigned len = (explicit_bracketing || !ref_tail_fields) ?
+ cp_end - cp : ref_tail_fields - cp;
+ unsigned indent = 0;
+
+ complain_at_indent (text_loc, &indent, _("invalid reference: %s"),
+ quote (text));
+ indent += SUB_INDENT;
+ if (midrule_rhs_index)
+ {
+ const char *format =
+ _("symbol not found in production before $%d: %.*s");
+ complain_at_indent (rule->location, &indent, format,
+ midrule_rhs_index, len, cp);
+ }
+ else
+ {
+ const char *format =
+ _("symbol not found in production: %.*s");
+ complain_at_indent (rule->location, &indent, format,
+ len, cp);
+ }
+
+ if (variant_count > 0)
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, false, indent);
+ return INVALID_REF;
+ }
+ case 1:
+ {
+ unsigned indent = 0;
+ if (variant_count > 1)
+ {
+ warn_at_indent (text_loc, &indent, _("misleading reference: %s"),
+ quote (text));
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, true, indent + SUB_INDENT);
+ }
+ {
+ unsigned symbol_index =
+ variant_table[valid_variant_index].symbol_index;
+ return (symbol_index == midrule_rhs_index) ? LHS_REF : symbol_index;
+ }
+ }
+ case 2:
+ default:
+ {
+ unsigned indent = 0;
+ complain_at_indent (text_loc, &indent, _("ambiguous reference: %s"),
+ quote (text));
+ show_sub_messages (cp, explicit_bracketing, midrule_rhs_index,
+ dollar_or_at, false, indent + SUB_INDENT);
+ return INVALID_REF;
+ }
}
+ /* Not reachable. */
return INVALID_REF;
}
@@ -617,7 +681,8 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
char *cp = text + 1;
char *gt_ptr = 0;
symbol_list *effective_rule;
- int effective_rule_length, n;
+ int effective_rule_length;
+ int n;
if (rule->midrule_parent_rule)
{
@@ -646,8 +711,8 @@ handle_action_dollar (symbol_list *rule, char *text, location dollar_loc)
tag_seen = true;
}
- n = parse_named_ref (cp, effective_rule, effective_rule_length,
- rule->midrule_parent_rhs_index, text, dollar_loc, '$');
+ n = parse_ref (cp, effective_rule, effective_rule_length,
+ rule->midrule_parent_rhs_index, text, dollar_loc, '$');
if (gt_ptr)
*gt_ptr = '\0';
@@ -722,7 +787,8 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
{
char *cp = text + 1;
symbol_list *effective_rule;
- int effective_rule_length, n;
+ int effective_rule_length;
+ int n;
if (rule->midrule_parent_rule)
{
@@ -737,7 +803,7 @@ handle_action_at (symbol_list *rule, char *text, location at_loc)
muscle_percent_define_ensure("locations", at_loc, true);
- n = parse_named_ref (cp, effective_rule, effective_rule_length,
+ n = parse_ref (cp, effective_rule, effective_rule_length,
rule->midrule_parent_rhs_index, text, at_loc, '@');
switch (n)
{
@@ -796,7 +862,8 @@ code_props_none_init (code_props *self)
code_props const code_props_none = CODE_PROPS_NONE_INIT;
void
-code_props_plain_init (code_props *self, char const *code, location code_loc)
+code_props_plain_init (code_props *self, char const *code,
+ location code_loc)
{
self->kind = CODE_PROPS_PLAIN;
self->code = code;
@@ -821,14 +888,14 @@ code_props_symbol_action_init (code_props *self, char const *code,
void
code_props_rule_action_init (code_props *self, char const *code,
location code_loc, symbol_list *rule,
- named_ref *named_ref)
+ named_ref *name)
{
self->kind = CODE_PROPS_RULE_ACTION;
self->code = code;
self->location = code_loc;
self->is_value_used = false;
self->rule = rule;
- self->named_ref = named_ref;
+ self->named_ref = name;
}
void
@@ -860,6 +927,8 @@ void
code_scanner_free (void)
{
obstack_free (&obstack_for_string, 0);
+ variant_table_free ();
+
/* Reclaim Flex's buffers. */
yylex_destroy ();
}