#include <assert.h>
-#include <stdlib.h>
#include <ctype.h>
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include "script/builtins.h"
#include "script/parser.h"
+#include "system/lt.h"
+#include "system/lt/lt_adapters.h"
+
+#define MAX_BUFFER_LENGTH (5 * 1000 * 1000)
+
+static struct ParseResult parse_expr(Gc *gc, struct Token current_token);
-static struct ParseResult parse_cdr(struct Token current_token)
+static struct ParseResult parse_cdr(Gc *gc, struct Token current_token)
{
if (*current_token.begin != '.') {
return parse_failure("Expected .", current_token.begin);
}
- struct ParseResult cdr = parse_expr(next_token(current_token.end));
+ struct ParseResult cdr = read_expr_from_string(gc, current_token.end);
if (cdr.is_error) {
return cdr;
}
current_token = next_token(cdr.end);
if (*current_token.begin != ')') {
- destroy_expr(cdr.expr);
return parse_failure("Expected )", current_token.begin);
}
return parse_success(cdr.expr, current_token.end);
}
-static struct ParseResult parse_cons(struct Token current_token)
+static struct ParseResult parse_list_end(Gc *gc, struct Token current_token)
+{
+ if (*current_token.begin != ')') {
+ return parse_failure("Expected )", current_token.begin);
+ }
+
+ return parse_success(atom_as_expr(create_symbol_atom(gc, "nil", NULL)),
+ current_token.end);
+}
+
+static struct ParseResult parse_list(Gc *gc, struct Token current_token)
{
if (*current_token.begin != '(') {
return parse_failure("Expected (", current_token.begin);
current_token = next_token(current_token.end);
if (*current_token.begin == ')') {
- return parse_success(atom_as_expr(create_symbol_atom("nil", NULL)), current_token.end);
+ return parse_list_end(gc, current_token);
}
- struct ParseResult car = parse_expr(current_token);
+ struct ParseResult car = parse_expr(gc, current_token);
if (car.is_error) {
return car;
}
- struct ParseResult cdr = parse_cdr(next_token(car.end));
+ struct Cons *list = create_cons(gc, car.expr, void_expr());
+ struct Cons *cons = list;
+ current_token = next_token(car.end);
+
+ while (*current_token.begin != '.' &&
+ *current_token.begin != ')' &&
+ *current_token.begin != 0) {
+ car = parse_expr(gc, current_token);
+ if (car.is_error) {
+ return car;
+ }
+
+ cons->cdr = cons_as_expr(create_cons(gc, car.expr, void_expr()));
+ cons = cons->cdr.cons;
+
+ current_token = next_token(car.end);
+ }
+
+ struct ParseResult cdr = *current_token.begin == '.'
+ ? parse_cdr(gc, current_token)
+ : parse_list_end(gc, current_token);
+
if (cdr.is_error) {
- destroy_expr(car.expr);
return cdr;
}
- return parse_success(cons_as_expr(create_cons(car.expr, cdr.expr)), cdr.end);
+ cons->cdr = cdr.expr;
+
+ return parse_success(cons_as_expr(list), cdr.end);
}
-static struct ParseResult parse_string(struct Token current_token)
+static struct ParseResult parse_string(Gc *gc, struct Token current_token)
{
if (*current_token.begin != '"') {
return parse_failure("Expected \"", current_token.begin);
}
if (current_token.begin + 1 == current_token.end) {
- return parse_success(atom_as_expr(create_string_atom("", NULL)),
+ return parse_success(atom_as_expr(create_string_atom(gc, "", NULL)),
current_token.end);
}
return parse_success(
atom_as_expr(
- create_string_atom(current_token.begin + 1, current_token.end - 1)),
+ create_string_atom(gc, current_token.begin + 1, current_token.end - 1)),
current_token.end);
}
-static struct ParseResult parse_number(struct Token current_token)
+static struct ParseResult parse_number(Gc *gc, struct Token current_token)
{
char *endptr = 0;
- const float x = strtof(current_token.begin, &endptr);
+ const long int x = strtoimax(current_token.begin, &endptr, 10);
if (current_token.begin == endptr || current_token.end != endptr) {
return parse_failure("Expected number", current_token.begin);
}
return parse_success(
- atom_as_expr(create_number_atom(x)),
+ atom_as_expr(create_number_atom(gc, x)),
current_token.end);
}
-static struct ParseResult parse_symbol(struct Token current_token)
+static struct ParseResult parse_symbol(Gc *gc, struct Token current_token)
{
if (*current_token.begin == 0) {
return parse_failure("EOF", current_token.begin);
}
return parse_success(
- atom_as_expr(create_symbol_atom(current_token.begin, current_token.end)),
+ atom_as_expr(create_symbol_atom(gc, current_token.begin, current_token.end)),
current_token.end);
}
-struct ParseResult parse_expr(struct Token current_token)
+static struct ParseResult parse_expr(Gc *gc, struct Token current_token)
{
if (*current_token.begin == 0) {
return parse_failure("EOF", current_token.begin);
}
- /* TODO: parse_expr doesn't parse lists */
-
switch (*current_token.begin) {
- case '(': return parse_cons(current_token);
+ case '(': return parse_list(gc, current_token);
/* TODO(#292): parser does not support escaped string characters */
- case '"': return parse_string(current_token);
+ case '"': return parse_string(gc, current_token);
+ case '\'': {
+ struct ParseResult result = parse_expr(gc, next_token(current_token.end));
+
+ if (result.is_error) {
+ return result;
+ }
+
+ result.expr = list(gc, 2, SYMBOL(gc, "quote"), result.expr);
+
+ return result;
+ } break;
default: {}
}
- if (isdigit(*current_token.begin)) {
- return parse_number(current_token);
+ if (*current_token.begin == '-' || isdigit(*current_token.begin)) {
+ struct ParseResult result = parse_number(gc, current_token);
+ if (!result.is_error) {
+ return result;
+ }
+ }
+
+ return parse_symbol(gc, current_token);
+}
+
+struct ParseResult read_expr_from_string(Gc *gc, const char *str)
+{
+ assert(str);
+ return parse_expr(gc, next_token(str));
+}
+
+struct ParseResult read_expr_from_file(Gc *gc, const char *filename)
+{
+ assert(filename);
+
+ Lt *lt = create_lt();
+ if (lt == NULL) {
+ return parse_failure("Could not create Lt object", NULL);
+ }
+
+ FILE *stream = PUSH_LT(lt, fopen(filename, "rb"), fclose_lt);
+ if (!stream) {
+ /* TODO(#307): ParseResult should not be used for reporting IO failures */
+ RETURN_LT(lt, parse_failure(strerror(errno), NULL));
+ }
+
+ if (fseek(stream, 0, SEEK_END) != 0) {
+ RETURN_LT(lt, parse_failure("Could not find the end of the file", NULL));
+ }
+
+ const long int buffer_length = ftell(stream);
+
+ if (buffer_length < 0) {
+ RETURN_LT(lt, parse_failure("Couldn't get the size of file", NULL));
}
- return parse_symbol(current_token);
+ if (buffer_length == 0) {
+ RETURN_LT(lt, parse_failure("File is empty", NULL));
+ }
+
+ if (buffer_length >= MAX_BUFFER_LENGTH) {
+ RETURN_LT(lt, parse_failure("File is too big", NULL));
+ }
+
+ if (fseek(stream, 0, SEEK_SET) != 0) {
+ RETURN_LT(lt, parse_failure("Could not find the beginning of the file", NULL));
+ }
+
+ char * const buffer = PUSH_LT(lt, malloc((size_t) buffer_length + 1), free);
+ if (buffer == NULL) {
+ RETURN_LT(lt, parse_failure(strerror(errno), NULL));
+ }
+
+ if (fread(buffer, 1, (size_t) buffer_length, stream) != (size_t) buffer_length) {
+ RETURN_LT(lt, parse_failure("Could not read the file", NULL));
+ }
+
+ struct ParseResult result = read_expr_from_string(gc, buffer);
+
+ RETURN_LT(lt, result);
}
struct ParseResult parse_success(struct Expr expr,
const char *str,
struct ParseResult result)
{
- /* TODO(#293): print_parse_error doesn't support colors */
/* TODO(#294): print_parse_error doesn't support multiple lines */
if (!result.is_error) {
return;
}
- fprintf(stream, "%s\n", str);
- for (size_t i = 0; i < (size_t) (result.end - str); ++i) {
- fprintf(stream, " ");
+ if (result.end) {
+ fprintf(stream, "%s\n", str);
+ for (size_t i = 0; i < (size_t) (result.end - str); ++i) {
+ fprintf(stream, " ");
+ }
+ fprintf(stream, "^\n");
}
- fprintf(stream, "^\n");
+
fprintf(stream, "%s\n", result.error_message);
}