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-rw-r--r--corebinutils/expr/expr.c923
1 files changed, 923 insertions, 0 deletions
diff --git a/corebinutils/expr/expr.c b/corebinutils/expr/expr.c
new file mode 100644
index 0000000000..6783f6afaf
--- /dev/null
+++ b/corebinutils/expr/expr.c
@@ -0,0 +1,923 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright (c) 2026 Project Tick
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Linux/musl-native port of FreeBSD expr(1).
+ * The original parser was expressed in yacc grammar form; this port keeps
+ * the same operator precedence and value semantics but uses a local
+ * recursive-descent parser so the standalone build does not depend on the
+ * FreeBSD build system or generated sources.
+ */
+
+#define _POSIX_C_SOURCE 200809L
+
+#include <ctype.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <locale.h>
+#include <regex.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ERR_EXIT 2
+
+enum value_type {
+ VALUE_INTEGER,
+ VALUE_NUMERIC_STRING,
+ VALUE_STRING,
+};
+
+struct value {
+ enum value_type type;
+ union {
+ intmax_t integer;
+ char *string;
+ } data;
+};
+
+struct parser {
+ const char *program;
+ char **argv;
+ int argc;
+ int index;
+ bool compat_mode;
+};
+
+static void usage(void) __attribute__((noreturn));
+static void vfail(struct parser *parser, bool with_errno, const char *fmt,
+ va_list ap) __attribute__((noreturn));
+static void fail(struct parser *parser, const char *fmt, ...)
+ __attribute__((format(printf, 2, 3), noreturn));
+static void fail_errno(struct parser *parser, const char *fmt, ...)
+ __attribute__((format(printf, 2, 3), noreturn));
+static void *xmalloc(struct parser *parser, size_t size);
+static char *xstrdup(struct parser *parser, const char *text);
+static bool is_operator_token(const char *token);
+static bool is_integer_literal(const char *text, bool compat_mode);
+static struct value value_from_integer(intmax_t integer);
+static struct value value_from_argument(struct parser *parser, const char *text);
+static void value_dispose(struct value *value);
+static struct value value_move(struct value *value);
+static bool value_try_to_integer(struct value *value);
+static void value_require_integer(struct parser *parser, struct value *value);
+static void value_require_string(struct parser *parser, struct value *value);
+static bool value_is_zero_or_null(struct value *value);
+static int compare_values(struct parser *parser, struct value *left,
+ struct value *right);
+static bool add_overflow(intmax_t left, intmax_t right, intmax_t *result);
+static bool sub_overflow(intmax_t left, intmax_t right, intmax_t *result);
+static uintmax_t intmax_magnitude(intmax_t value);
+static bool mul_overflow(intmax_t left, intmax_t right, intmax_t *result);
+static struct value value_or(struct value *left, struct value *right);
+static struct value value_and(struct value *left, struct value *right);
+static struct value value_compare_eq(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_compare_ne(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_compare_lt(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_compare_le(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_compare_gt(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_compare_ge(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_add(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_sub(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_mul(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_div(struct parser *parser, struct value *left,
+ struct value *right);
+static struct value value_rem(struct parser *parser, struct value *left,
+ struct value *right);
+static char *dup_substring(struct parser *parser, const char *text, regoff_t start,
+ regoff_t end);
+static struct value value_match(struct parser *parser, struct value *left,
+ struct value *right);
+static const char *peek_token(const struct parser *parser);
+static bool match_token(struct parser *parser, const char *token);
+static struct value parse_expression(struct parser *parser);
+static struct value parse_or(struct parser *parser);
+static struct value parse_and(struct parser *parser);
+static struct value parse_compare(struct parser *parser);
+static struct value parse_add(struct parser *parser);
+static struct value parse_mul(struct parser *parser);
+static struct value parse_match_expr(struct parser *parser);
+static struct value parse_primary(struct parser *parser);
+static void write_result(struct parser *parser, const struct value *value);
+
+static void
+usage(void)
+{
+ fprintf(stderr, "usage: expr [-e] [--] expression\n");
+ exit(ERR_EXIT);
+}
+
+static void
+vfail(struct parser *parser, bool with_errno, const char *fmt, va_list ap)
+{
+ int saved_errno;
+
+ saved_errno = errno;
+ fprintf(stderr, "%s: ", parser->program);
+ vfprintf(stderr, fmt, ap);
+ if (with_errno) {
+ fprintf(stderr, ": %s",
+ saved_errno == 0 ? "I/O error" : strerror(saved_errno));
+ }
+ fputc('\n', stderr);
+ exit(ERR_EXIT);
+}
+
+static void
+fail(struct parser *parser, const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ vfail(parser, false, fmt, ap);
+ va_end(ap);
+}
+
+static void
+fail_errno(struct parser *parser, const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ vfail(parser, true, fmt, ap);
+ va_end(ap);
+}
+
+static void *
+xmalloc(struct parser *parser, size_t size)
+{
+ void *memory;
+
+ if (size == 0) {
+ size = 1;
+ }
+ memory = malloc(size);
+ if (memory == NULL) {
+ fail(parser, "malloc failed");
+ }
+ return (memory);
+}
+
+static char *
+xstrdup(struct parser *parser, const char *text)
+{
+ size_t length;
+ char *copy;
+
+ length = strlen(text) + 1;
+ copy = xmalloc(parser, length);
+ memcpy(copy, text, length);
+ return (copy);
+}
+
+static bool
+is_operator_token(const char *token)
+{
+ static const char *const operators[] = {
+ "|",
+ "&",
+ "=",
+ ">",
+ "<",
+ ">=",
+ "<=",
+ "!=",
+ "+",
+ "-",
+ "*",
+ "/",
+ "%",
+ ":",
+ "(",
+ ")",
+ };
+ size_t i;
+
+ for (i = 0; i < sizeof(operators) / sizeof(operators[0]); i++) {
+ if (strcmp(token, operators[i]) == 0) {
+ return (true);
+ }
+ }
+ return (false);
+}
+
+static bool
+is_integer_literal(const char *text, bool compat_mode)
+{
+ const unsigned char *cursor;
+
+ cursor = (const unsigned char *)text;
+ if (compat_mode) {
+ if (*cursor == '\0') {
+ return (true);
+ }
+ while (isspace(*cursor) != 0) {
+ cursor++;
+ }
+ }
+ if (*cursor == '-' || (compat_mode && *cursor == '+')) {
+ cursor++;
+ }
+ if (*cursor == '\0') {
+ return (false);
+ }
+ while (isdigit(*cursor) != 0) {
+ cursor++;
+ }
+ return (*cursor == '\0');
+}
+
+static struct value
+value_from_integer(intmax_t integer)
+{
+ struct value value;
+
+ value.type = VALUE_INTEGER;
+ value.data.integer = integer;
+ return (value);
+}
+
+static struct value
+value_from_argument(struct parser *parser, const char *text)
+{
+ struct value value;
+
+ value.data.string = xstrdup(parser, text);
+ value.type = is_integer_literal(text, parser->compat_mode) ?
+ VALUE_NUMERIC_STRING : VALUE_STRING;
+ return (value);
+}
+
+static void
+value_dispose(struct value *value)
+{
+ if (value->type == VALUE_NUMERIC_STRING || value->type == VALUE_STRING) {
+ free(value->data.string);
+ }
+ value->type = VALUE_INTEGER;
+ value->data.integer = 0;
+}
+
+static struct value
+value_move(struct value *value)
+{
+ struct value moved;
+
+ moved = *value;
+ value->type = VALUE_INTEGER;
+ value->data.integer = 0;
+ return (moved);
+}
+
+static bool
+value_try_to_integer(struct value *value)
+{
+ intmax_t parsed;
+ char *end;
+
+ if (value->type == VALUE_INTEGER) {
+ return (true);
+ }
+ if (value->type != VALUE_NUMERIC_STRING) {
+ return (false);
+ }
+
+ errno = 0;
+ end = NULL;
+ parsed = strtoimax(value->data.string, &end, 10);
+ if (errno == ERANGE || end == NULL || *end != '\0') {
+ return (false);
+ }
+
+ free(value->data.string);
+ value->type = VALUE_INTEGER;
+ value->data.integer = parsed;
+ return (true);
+}
+
+static void
+value_require_integer(struct parser *parser, struct value *value)
+{
+ if (value->type == VALUE_STRING) {
+ fail(parser, "not a decimal number: '%s'", value->data.string);
+ }
+ if (!value_try_to_integer(value)) {
+ fail(parser, "operand too large: '%s'", value->data.string);
+ }
+}
+
+static void
+value_require_string(struct parser *parser, struct value *value)
+{
+ int length;
+ size_t size;
+ char *buffer;
+
+ if (value->type != VALUE_INTEGER) {
+ return;
+ }
+
+ length = snprintf(NULL, 0, "%jd", value->data.integer);
+ if (length < 0) {
+ fail(parser, "failed to format integer result");
+ }
+ size = (size_t)length + 1;
+ buffer = xmalloc(parser, size);
+ if (snprintf(buffer, size, "%jd", value->data.integer) != length) {
+ free(buffer);
+ fail(parser, "failed to format integer result");
+ }
+ value->type = VALUE_STRING;
+ value->data.string = buffer;
+}
+
+static bool
+value_is_zero_or_null(struct value *value)
+{
+ if (value->type == VALUE_INTEGER) {
+ return (value->data.integer == 0);
+ }
+ if (value->data.string[0] == '\0') {
+ return (true);
+ }
+ return (value_try_to_integer(value) && value->data.integer == 0);
+}
+
+static int
+compare_values(struct parser *parser, struct value *left, struct value *right)
+{
+ int result;
+
+ if (left->type == VALUE_STRING || right->type == VALUE_STRING) {
+ value_require_string(parser, left);
+ value_require_string(parser, right);
+ result = strcoll(left->data.string, right->data.string);
+ } else {
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (left->data.integer > right->data.integer) {
+ result = 1;
+ } else if (left->data.integer < right->data.integer) {
+ result = -1;
+ } else {
+ result = 0;
+ }
+ }
+
+ value_dispose(left);
+ value_dispose(right);
+ return (result);
+}
+
+static bool
+add_overflow(intmax_t left, intmax_t right, intmax_t *result)
+{
+ if (right > 0 && left > INTMAX_MAX - right) {
+ return (true);
+ }
+ if (right < 0 && left < INTMAX_MIN - right) {
+ return (true);
+ }
+ *result = left + right;
+ return (false);
+}
+
+static bool
+sub_overflow(intmax_t left, intmax_t right, intmax_t *result)
+{
+ if (right > 0 && left < INTMAX_MIN + right) {
+ return (true);
+ }
+ if (right < 0 && left > INTMAX_MAX + right) {
+ return (true);
+ }
+ *result = left - right;
+ return (false);
+}
+
+static uintmax_t
+intmax_magnitude(intmax_t value)
+{
+ if (value >= 0) {
+ return ((uintmax_t)value);
+ }
+ return ((uintmax_t)(-(value + 1)) + 1U);
+}
+
+static bool
+mul_overflow(intmax_t left, intmax_t right, intmax_t *result)
+{
+ uintmax_t left_abs;
+ uintmax_t right_abs;
+ uintmax_t limit;
+ uintmax_t product;
+ bool negative;
+
+ if (left == 0 || right == 0) {
+ *result = 0;
+ return (false);
+ }
+
+ left_abs = intmax_magnitude(left);
+ right_abs = intmax_magnitude(right);
+ negative = ((left < 0) != (right < 0));
+ limit = negative ? ((uintmax_t)INTMAX_MAX + 1U) : (uintmax_t)INTMAX_MAX;
+
+ if (right_abs > limit / left_abs) {
+ return (true);
+ }
+
+ product = left_abs * right_abs;
+ if (!negative) {
+ *result = (intmax_t)product;
+ return (false);
+ }
+ if (product == (uintmax_t)INTMAX_MAX + 1U) {
+ *result = INTMAX_MIN;
+ return (false);
+ }
+ *result = -(intmax_t)product;
+ return (false);
+}
+
+static struct value
+value_or(struct value *left, struct value *right)
+{
+ if (!value_is_zero_or_null(left)) {
+ value_dispose(right);
+ return (value_move(left));
+ }
+ value_dispose(left);
+ if (!value_is_zero_or_null(right)) {
+ return (value_move(right));
+ }
+ value_dispose(right);
+ return (value_from_integer(0));
+}
+
+static struct value
+value_and(struct value *left, struct value *right)
+{
+ if (value_is_zero_or_null(left) || value_is_zero_or_null(right)) {
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(0));
+ }
+ value_dispose(right);
+ return (value_move(left));
+}
+
+static struct value
+value_compare_eq(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) == 0));
+}
+
+static struct value
+value_compare_ne(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) != 0));
+}
+
+static struct value
+value_compare_lt(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) < 0));
+}
+
+static struct value
+value_compare_le(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) <= 0));
+}
+
+static struct value
+value_compare_gt(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) > 0));
+}
+
+static struct value
+value_compare_ge(struct parser *parser, struct value *left, struct value *right)
+{
+ return (value_from_integer(compare_values(parser, left, right) >= 0));
+}
+
+static struct value
+value_add(struct parser *parser, struct value *left, struct value *right)
+{
+ intmax_t result;
+
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (add_overflow(left->data.integer, right->data.integer, &result)) {
+ fail(parser, "overflow");
+ }
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(result));
+}
+
+static struct value
+value_sub(struct parser *parser, struct value *left, struct value *right)
+{
+ intmax_t result;
+
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (sub_overflow(left->data.integer, right->data.integer, &result)) {
+ fail(parser, "overflow");
+ }
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(result));
+}
+
+static struct value
+value_mul(struct parser *parser, struct value *left, struct value *right)
+{
+ intmax_t result;
+
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (mul_overflow(left->data.integer, right->data.integer, &result)) {
+ fail(parser, "overflow");
+ }
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(result));
+}
+
+static struct value
+value_div(struct parser *parser, struct value *left, struct value *right)
+{
+ intmax_t result;
+
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (right->data.integer == 0) {
+ fail(parser, "division by zero");
+ }
+ if (left->data.integer == INTMAX_MIN && right->data.integer == -1) {
+ fail(parser, "overflow");
+ }
+ result = left->data.integer / right->data.integer;
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(result));
+}
+
+static struct value
+value_rem(struct parser *parser, struct value *left, struct value *right)
+{
+ intmax_t result;
+
+ value_require_integer(parser, left);
+ value_require_integer(parser, right);
+ if (right->data.integer == 0) {
+ fail(parser, "division by zero");
+ }
+ result = left->data.integer % right->data.integer;
+ value_dispose(left);
+ value_dispose(right);
+ return (value_from_integer(result));
+}
+
+static char *
+dup_substring(struct parser *parser, const char *text, regoff_t start, regoff_t end)
+{
+ size_t length;
+ char *result;
+
+ if (start < 0 || end < start) {
+ fail(parser, "regular expression returned an invalid capture range");
+ }
+ length = (size_t)(end - start);
+ result = xmalloc(parser, length + 1);
+ memcpy(result, text + start, length);
+ result[length] = '\0';
+ return (result);
+}
+
+static struct value
+value_match(struct parser *parser, struct value *left, struct value *right)
+{
+ regex_t regex;
+ regmatch_t matches[2];
+ struct value result;
+ size_t error_length;
+ char *error_text;
+ int regcomp_result;
+ int regexec_result;
+
+ value_require_string(parser, left);
+ value_require_string(parser, right);
+
+ regcomp_result = regcomp(&regex, right->data.string, 0);
+ if (regcomp_result != 0) {
+ error_length = regerror(regcomp_result, &regex, NULL, 0);
+ error_text = xmalloc(parser, error_length);
+ (void)regerror(regcomp_result, &regex, error_text, error_length);
+ fail(parser, "regular expression error: %s", error_text);
+ }
+
+ regexec_result = regexec(&regex, left->data.string,
+ (size_t)(sizeof(matches) / sizeof(matches[0])), matches, 0);
+ if (regexec_result == 0 && matches[0].rm_so == 0) {
+ if (matches[1].rm_so >= 0) {
+ result.type = VALUE_STRING;
+ result.data.string = dup_substring(parser, left->data.string,
+ matches[1].rm_so, matches[1].rm_eo);
+ } else {
+ result = value_from_integer(matches[0].rm_eo);
+ }
+ } else if (regexec_result == REG_NOMATCH ||
+ (regexec_result == 0 && matches[0].rm_so != 0)) {
+ if (regex.re_nsub == 0) {
+ result = value_from_integer(0);
+ } else {
+ result.type = VALUE_STRING;
+ result.data.string = xstrdup(parser, "");
+ }
+ } else {
+ error_length = regerror(regexec_result, &regex, NULL, 0);
+ error_text = xmalloc(parser, error_length);
+ (void)regerror(regexec_result, &regex, error_text, error_length);
+ regfree(&regex);
+ fail(parser, "regular expression execution failed: %s", error_text);
+ }
+
+ regfree(&regex);
+ value_dispose(left);
+ value_dispose(right);
+ return (result);
+}
+
+static const char *
+peek_token(const struct parser *parser)
+{
+ if (parser->index >= parser->argc) {
+ return (NULL);
+ }
+ return (parser->argv[parser->index]);
+}
+
+static bool
+match_token(struct parser *parser, const char *token)
+{
+ const char *current;
+
+ current = peek_token(parser);
+ if (current == NULL || strcmp(current, token) != 0) {
+ return (false);
+ }
+ parser->index++;
+ return (true);
+}
+
+static struct value
+parse_expression(struct parser *parser)
+{
+ return (parse_or(parser));
+}
+
+static struct value
+parse_or(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_and(parser);
+ while (match_token(parser, "|")) {
+ right = parse_and(parser);
+ left = value_or(&left, &right);
+ }
+ return (left);
+}
+
+static struct value
+parse_and(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_compare(parser);
+ while (match_token(parser, "&")) {
+ right = parse_compare(parser);
+ left = value_and(&left, &right);
+ }
+ return (left);
+}
+
+static struct value
+parse_compare(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_add(parser);
+ for (;;) {
+ if (match_token(parser, "=")) {
+ right = parse_add(parser);
+ left = value_compare_eq(parser, &left, &right);
+ } else if (match_token(parser, "!=")) {
+ right = parse_add(parser);
+ left = value_compare_ne(parser, &left, &right);
+ } else if (match_token(parser, ">=")) {
+ right = parse_add(parser);
+ left = value_compare_ge(parser, &left, &right);
+ } else if (match_token(parser, "<=")) {
+ right = parse_add(parser);
+ left = value_compare_le(parser, &left, &right);
+ } else if (match_token(parser, ">")) {
+ right = parse_add(parser);
+ left = value_compare_gt(parser, &left, &right);
+ } else if (match_token(parser, "<")) {
+ right = parse_add(parser);
+ left = value_compare_lt(parser, &left, &right);
+ } else {
+ break;
+ }
+ }
+ return (left);
+}
+
+static struct value
+parse_add(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_mul(parser);
+ for (;;) {
+ if (match_token(parser, "+")) {
+ right = parse_mul(parser);
+ left = value_add(parser, &left, &right);
+ } else if (match_token(parser, "-")) {
+ right = parse_mul(parser);
+ left = value_sub(parser, &left, &right);
+ } else {
+ break;
+ }
+ }
+ return (left);
+}
+
+static struct value
+parse_mul(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_match_expr(parser);
+ for (;;) {
+ if (match_token(parser, "*")) {
+ right = parse_match_expr(parser);
+ left = value_mul(parser, &left, &right);
+ } else if (match_token(parser, "/")) {
+ right = parse_match_expr(parser);
+ left = value_div(parser, &left, &right);
+ } else if (match_token(parser, "%")) {
+ right = parse_match_expr(parser);
+ left = value_rem(parser, &left, &right);
+ } else {
+ break;
+ }
+ }
+ return (left);
+}
+
+static struct value
+parse_match_expr(struct parser *parser)
+{
+ struct value left;
+ struct value right;
+
+ left = parse_primary(parser);
+ while (match_token(parser, ":")) {
+ right = parse_primary(parser);
+ left = value_match(parser, &left, &right);
+ }
+ return (left);
+}
+
+static struct value
+parse_primary(struct parser *parser)
+{
+ const char *token;
+ struct value value;
+
+ token = peek_token(parser);
+ if (token == NULL) {
+ fail(parser, "syntax error");
+ }
+ if (match_token(parser, "(")) {
+ value = parse_expression(parser);
+ if (!match_token(parser, ")")) {
+ value_dispose(&value);
+ fail(parser, "syntax error");
+ }
+ return (value);
+ }
+ if (is_operator_token(token)) {
+ fail(parser, "syntax error");
+ }
+ parser->index++;
+ return (value_from_argument(parser, token));
+}
+
+static void
+write_result(struct parser *parser, const struct value *value)
+{
+ int rc;
+
+ if (value->type == VALUE_INTEGER) {
+ rc = fprintf(stdout, "%jd\n", value->data.integer);
+ } else {
+ rc = fprintf(stdout, "%s\n", value->data.string);
+ }
+ if (rc < 0 || fflush(stdout) == EOF) {
+ fail_errno(parser, "write failed");
+ }
+}
+
+int
+main(int argc, char *argv[])
+{
+ struct parser parser;
+ struct value result;
+ const char *arg;
+ int i;
+
+ (void)setlocale(LC_ALL, "");
+
+ parser.program = argv[0] == NULL ? "expr" : argv[0];
+ if (strrchr(parser.program, '/') != NULL) {
+ parser.program = strrchr(parser.program, '/') + 1;
+ }
+ parser.compat_mode = false;
+ parser.index = 0;
+ parser.argv = NULL;
+ parser.argc = 0;
+
+ i = 1;
+ while (i < argc) {
+ arg = argv[i];
+ if (strcmp(arg, "--") == 0) {
+ i++;
+ break;
+ }
+ if (strcmp(arg, "-e") == 0) {
+ parser.compat_mode = true;
+ i++;
+ continue;
+ }
+ if (arg[0] == '-' && arg[1] != '\0') {
+ usage();
+ }
+ break;
+ }
+
+ parser.argv = argv + i;
+ parser.argc = argc - i;
+ if (parser.argc == 0) {
+ usage();
+ }
+
+ result = parse_expression(&parser);
+ if (peek_token(&parser) != NULL) {
+ value_dispose(&result);
+ fail(&parser, "syntax error");
+ }
+
+ write_result(&parser, &result);
+ i = value_is_zero_or_null(&result) ? 1 : 0;
+ value_dispose(&result);
+ return (i);
+}
generated by cgit 0.0.5-2-1-g0f52 (git 2.46.0) at 2026-04-06 06:02:58 +0000