pub_soft/abseil-cpp
3
0
Fork 0
mirror of https://github.com/abseil/abseil-cpp.git synced 2026-06-04 12:07:05 +08:00
Code Issues Packages Projects Releases Wiki Activity

Use new emscripten_errn to avoid copying strings.

Browse Source 
PiperOrigin-RevId: 547895328
Change-Id: If5da952604415fa6ed2402052f80add6c4b7dfb3
This commit is contained in:
Abseil Team
2023-07-13 13:05:05 -07:00
committed by Copybara-Service
parent b8ebbc2eca
commit c16a2f4320
2 changed files with 28 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
absl/base/internal/raw_logging.cc
View File

@@ -206,27 +206,32 @@ void DefaultInternalLog(absl::LogSeverity severity, const char* file, int line,
} // namespace
void AsyncSignalSafeWriteError(const char* s, size_t len) {
if (!len) return;
absl::base_internal::ErrnoSaver errno_saver;
#if defined(__EMSCRIPTEN__)
// In WebAssembly, bypass filesystem emulation via fwrite.
// TODO(b/282811932): Avoid this copy if these emscripten functions can
// be updated to accept size directly.
if (s[len - 1] == '\n') {
// Skip a trailing newline character as emscripten_errn adds one itself.
len--;
}
// emscripten_errn was introduced in 3.1.41 but broken in standalone mode
// until 3.1.43.
#if ABSL_INTERNAL_EMSCRIPTEN_VERSION >= 3001043
emscripten_errn(s, len);
#else
char buf[kLogBufSize];
if (len >= kLogBufSize) {
len = kLogBufSize - 1;
size_t trunc_len = sizeof(kTruncated) - 2;
strncpy(buf + len - trunc_len, kTruncated, trunc_len);
constexpr size_t trunc_len = sizeof(kTruncated) - 2;
memcpy(buf + len - trunc_len, kTruncated, trunc_len);
buf[len] = '\0';
len -= trunc_len;
} else if (len && s[len - 1] == '\n') {
len--;
}
strncpy(buf, s, len);
if (len) {
} else {
buf[len] = '\0';
// Skip a trailing newline character as emscripten_err adds one itself.
_emscripten_err(buf);
}
memcpy(buf, s, len);
_emscripten_err(buf);
#endif
#elif defined(ABSL_HAVE_SYSCALL_WRITE)
// We prefer calling write via `syscall` to minimize the risk of libc doing
// something "helpful".

19
absl/log/internal/globals.cc
View File

@@ -16,6 +16,7 @@
#include <atomic>
#include <cstdio>
#if defined(__EMSCRIPTEN__)
#include <emscripten/console.h>
#endif
@@ -25,6 +26,7 @@
#include "absl/base/internal/raw_logging.h"
#include "absl/base/log_severity.h"
#include "absl/strings/string_view.h"
#include "absl/strings/strip.h"
#include "absl/time/time.h"
namespace absl {
@@ -58,16 +60,19 @@ void SetInitialized() {
}
void WriteToStderr(absl::string_view message, absl::LogSeverity severity) {
if (message.empty()) return;
#if defined(__EMSCRIPTEN__)
// In WebAssembly, bypass filesystem emulation via fwrite.
// TODO(b/282811932): Avoid this copy if these emscripten functions can
// be updated to accept size directly.
std::string null_terminated_message(message);
if (!null_terminated_message.empty() &&
null_terminated_message.back() == '\n') {
null_terminated_message.pop_back();
}
// Skip a trailing newline character as emscripten_errn adds one itself.
const auto message_minus_newline = absl::StripSuffix(message, "\n");
// emscripten_errn was introduced in 3.1.41 but broken in standalone mode
// until 3.1.43.
#if ABSL_INTERNAL_EMSCRIPTEN_VERSION >= 3001043
emscripten_errn(message_minus_newline.data(), message_minus_newline.size());
#else
std::string null_terminated_message(message_minus_newline);
_emscripten_err(null_terminated_message.c_str());
#endif
#else
// Avoid using std::cerr from this module since we may get called during
// exit code, and cerr may be partially or fully destroyed by then.