Convert `strtoll` to use `std::from_chars`.
This CL updates the lexer to use `std::from_chars` which is locale
independent over `strtoll` which honours locale.
Bug: tint:1686
Change-Id: Ic773038fffaa9e2042dec9d94e310c73d05180b8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/122603
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
diff --git a/src/tint/reader/wgsl/lexer.cc b/src/tint/reader/wgsl/lexer.cc
index 5171e4c..28fb135 100644
--- a/src/tint/reader/wgsl/lexer.cc
+++ b/src/tint/reader/wgsl/lexer.cc
@@ -15,6 +15,7 @@
#include "src/tint/reader/wgsl/lexer.h"
#include <cctype>
+#include <charconv>
#include <cmath>
#include <cstring>
#include <functional>
@@ -804,41 +805,48 @@
return {Token::Type::kFloatLiteral, source, result_f64};
}
-Token Lexer::build_token_from_int_if_possible(Source source, size_t start, int32_t base) {
+Token Lexer::build_token_from_int_if_possible(Source source,
+ size_t start,
+ size_t prefix_count,
+ int32_t base) {
const char* start_ptr = &at(start);
- char* end_ptr = nullptr;
+ // The call to `from_chars` will return the pointer to just after the last parsed character.
+ // We also need to tell it the maximum end character to parse. So, instead of walking all the
+ // characters to find the last possible and using that, we just provide the end of the string.
+ // We then calculate the count based off the provided end pointer and the start pointer. The
+ // extra `prefix_count` is to handle a `0x` which is not included in the `start` value.
+ const char* end_ptr = &at(length() - 1) + 1;
- errno = 0;
- int64_t res = strtoll(start_ptr, &end_ptr, base);
- const bool overflow = errno == ERANGE;
-
- if (end_ptr) {
- advance(static_cast<size_t>(end_ptr - start_ptr));
- }
+ int64_t value = 0;
+ auto res = std::from_chars(start_ptr, end_ptr, value, base);
+ const bool overflow = res.ec != std::errc();
+ advance(static_cast<size_t>(res.ptr - start_ptr) + prefix_count);
if (matches(pos(), 'u')) {
- if (!overflow && CheckedConvert<u32>(AInt(res))) {
+ if (!overflow && CheckedConvert<u32>(AInt(value))) {
advance(1);
end_source(source);
- return {Token::Type::kIntLiteral_U, source, res};
+ return {Token::Type::kIntLiteral_U, source, value};
}
return {Token::Type::kError, source, "value cannot be represented as 'u32'"};
}
if (matches(pos(), 'i')) {
- if (!overflow && CheckedConvert<i32>(AInt(res))) {
+ if (!overflow && CheckedConvert<i32>(AInt(value))) {
advance(1);
end_source(source);
- return {Token::Type::kIntLiteral_I, source, res};
+ return {Token::Type::kIntLiteral_I, source, value};
}
return {Token::Type::kError, source, "value cannot be represented as 'i32'"};
}
- end_source(source);
+ // Check this last in order to get the more specific sized error messages
if (overflow) {
return {Token::Type::kError, source, "value cannot be represented as 'abstract-int'"};
}
- return {Token::Type::kIntLiteral, source, res};
+
+ end_source(source);
+ return {Token::Type::kIntLiteral, source, value};
}
Token Lexer::try_hex_integer() {
@@ -858,7 +866,7 @@
"integer or float hex literal has no significant digits"};
}
- return build_token_from_int_if_possible(source, start, 16);
+ return build_token_from_int_if_possible(source, curr, curr - start, 16);
}
Token Lexer::try_integer() {
@@ -879,7 +887,7 @@
}
}
- return build_token_from_int_if_possible(source, start, 10);
+ return build_token_from_int_if_possible(source, start, 0, 10);
}
Token Lexer::try_ident() {
diff --git a/src/tint/reader/wgsl/lexer.h b/src/tint/reader/wgsl/lexer.h
index 8e0306b..ac41dae 100644
--- a/src/tint/reader/wgsl/lexer.h
+++ b/src/tint/reader/wgsl/lexer.h
@@ -47,7 +47,10 @@
/// @returns uninitialized token on success, or error
Token skip_comment();
- Token build_token_from_int_if_possible(Source source, size_t start, int32_t base);
+ Token build_token_from_int_if_possible(Source source,
+ size_t start,
+ size_t prefix_count,
+ int32_t base);
Token check_keyword(const Source&, std::string_view);
