Roll abseil_revision 8d9cef25c7..5073947530

Change Log:
https://chromium.googlesource.com/external/github.com/abseil/abseil-cpp/+log/8d9cef25c7..5073947530
Full diff:
https://chromium.googlesource.com/external/github.com/abseil/abseil-cpp/+/8d9cef25c7..5073947530

Bug: None
Change-Id: I56b369aaff8346b596ef5a49db7d4a9b048a5875
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3641703
Reviewed-by: Mirko Bonadei <mbonadei@chromium.org>
Commit-Queue: Danil Chapovalov <danilchap@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1002000}

third_party/abseil-cpp/README.chromium

@@ -4,7 +4,7 @@ URL: https://github.com/abseil/abseil-cpp
 License: Apache 2.0
 License File: LICENSE
 Version: 0
-Revision: 8d9cef25c70321c794ff5559cc0b1e0fa5f85e72
+Revision: 5073947530a9c74ce6da63b1fac16cc07564a3b8
 Security Critical: yes
 
 Description:

third_party/abseil-cpp/absl/base/BUILD.bazel

@@ -75,6 +75,7 @@ cc_library(
         ":atomic_hook",
         ":config",
         ":core_headers",
+        ":errno_saver",
         ":log_severity",
     ],
 )

third_party/abseil-cpp/absl/base/BUILD.gn

@@ -35,6 +35,7 @@ absl_source_set("raw_logging_internal") {
     ":atomic_hook",
     ":config",
     ":core_headers",
+    ":errno_saver",
     ":log_severity",
   ]
   visibility = [ "//third_party/abseil-cpp/absl/*" ]

third_party/abseil-cpp/absl/base/CMakeLists.txt

@@ -66,6 +66,7 @@ absl_cc_library(
     absl::atomic_hook
     absl::config
     absl::core_headers
+    absl::errno_saver
     absl::log_severity
   COPTS
     ${ABSL_DEFAULT_COPTS}

third_party/abseil-cpp/absl/base/internal/raw_logging.cc

@@ -14,15 +14,17 @@
 
 #include "absl/base/internal/raw_logging.h"
 
-#include <stddef.h>
 #include <cstdarg>
+#include <cstddef>
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <string>
 
 #include "absl/base/attributes.h"
 #include "absl/base/config.h"
 #include "absl/base/internal/atomic_hook.h"
+#include "absl/base/internal/errno_saver.h"
 #include "absl/base/log_severity.h"
 
 // We know how to perform low-level writes to stderr in POSIX and Windows.  For
@@ -78,11 +80,10 @@ namespace {
 // a selected set of platforms for which we expect not to be able to raw log.
 
 ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
-    absl::base_internal::AtomicHook<LogPrefixHook>
-        log_prefix_hook;
+absl::base_internal::AtomicHook<LogFilterAndPrefixHook>
+    log_filter_and_prefix_hook;
 ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES
-    absl::base_internal::AtomicHook<AbortHook>
-        abort_hook;
+absl::base_internal::AtomicHook<AbortHook> abort_hook;
 
 #ifdef ABSL_LOW_LEVEL_WRITE_SUPPORTED
 constexpr char kTruncated[] = " ... (message truncated)\n";
@@ -151,9 +152,9 @@ void RawLogVA(absl::LogSeverity severity, const char* file, int line,
   }
 #endif
 
-  auto log_prefix_hook_ptr = log_prefix_hook.Load();
-  if (log_prefix_hook_ptr) {
-    enabled = log_prefix_hook_ptr(severity, file, line, &buf, &size);
+  auto log_filter_and_prefix_hook_ptr = log_filter_and_prefix_hook.Load();
+  if (log_filter_and_prefix_hook_ptr) {
+    enabled = log_filter_and_prefix_hook_ptr(severity, file, line, &buf, &size);
   } else {
     if (enabled) {
       DoRawLog(&buf, &size, "[%s : %d] RAW: ", file, line);
@@ -169,7 +170,7 @@ void RawLogVA(absl::LogSeverity severity, const char* file, int line,
     } else {
       DoRawLog(&buf, &size, "%s", kTruncated);
     }
-    SafeWriteToStderr(buffer, strlen(buffer));
+    AsyncSignalSafeWriteToStderr(buffer, strlen(buffer));
   }
 #else
   static_cast<void>(format);
@@ -196,8 +197,11 @@ void DefaultInternalLog(absl::LogSeverity severity, const char* file, int line,
 
 }  // namespace
 
-void SafeWriteToStderr(const char *s, size_t len) {
+void AsyncSignalSafeWriteToStderr(const char* s, size_t len) {
+  absl::base_internal::ErrnoSaver errno_saver;
 #if defined(ABSL_HAVE_SYSCALL_WRITE)
+  // We prefer calling write via `syscall` to minimize the risk of libc doing
+  // something "helpful".
   syscall(SYS_write, STDERR_FILENO, s, len);
 #elif defined(ABSL_HAVE_POSIX_WRITE)
   write(STDERR_FILENO, s, len);
@@ -230,7 +234,9 @@ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL
     absl::base_internal::AtomicHook<InternalLogFunction>
         internal_log_function(DefaultInternalLog);
 
-void RegisterLogPrefixHook(LogPrefixHook func) { log_prefix_hook.Store(func); }
+void RegisterLogFilterAndPrefixHook(LogFilterAndPrefixHook func) {
+  log_filter_and_prefix_hook.Store(func);
+}
 
 void RegisterAbortHook(AbortHook func) { abort_hook.Store(func); }
 

third_party/abseil-cpp/absl/base/internal/raw_logging.h

@@ -109,12 +109,9 @@ namespace raw_logging_internal {
 void RawLog(absl::LogSeverity severity, const char* file, int line,
             const char* format, ...) ABSL_PRINTF_ATTRIBUTE(4, 5);
 
-// Writes the provided buffer directly to stderr, in a safe, low-level manner.
-//
-// In POSIX this means calling write(), which is async-signal safe and does
-// not malloc.  If the platform supports the SYS_write syscall, we invoke that
-// directly to side-step any libc interception.
-void SafeWriteToStderr(const char *s, size_t len);
+// Writes the provided buffer directly to stderr, in a signal-safe, low-level
+// manner.
+void AsyncSignalSafeWriteToStderr(const char* s, size_t len);
 
 // compile-time function to get the "base" filename, that is, the part of
 // a filename after the last "/" or "\" path separator.  The search starts at
@@ -148,11 +145,12 @@ bool RawLoggingFullySupported();
 // 'severity' is the severity level of the message being written.
 // 'file' and 'line' are the file and line number where the ABSL_RAW_LOG macro
 // was located.
-// 'buffer' and 'buf_size' are pointers to the buffer and buffer size.  If the
-// hook writes a prefix, it must increment *buffer and decrement *buf_size
+// 'buf' and 'buf_size' are pointers to the buffer and buffer size.  If the
+// hook writes a prefix, it must increment *buf and decrement *buf_size
 // accordingly.
-using LogPrefixHook = bool (*)(absl::LogSeverity severity, const char* file,
-                               int line, char** buffer, int* buf_size);
+using LogFilterAndPrefixHook = bool (*)(absl::LogSeverity severity,
+                                        const char* file, int line, char** buf,
+                                        int* buf_size);
 
 // Function type for a raw_logging customization hook called to abort a process
 // when a FATAL message is logged.  If the provided AbortHook() returns, the
@@ -162,7 +160,10 @@ using LogPrefixHook = bool (*)(absl::LogSeverity severity, const char* file,
 // was located.
 // The NUL-terminated logged message lives in the buffer between 'buf_start'
 // and 'buf_end'.  'prefix_end' points to the first non-prefix character of the
-// buffer (as written by the LogPrefixHook.)
+// buffer (as written by the LogFilterAndPrefixHook.)
+//
+// The lifetime of the filename and message buffers will not end while the
+// process remains alive.
 using AbortHook = void (*)(const char* file, int line, const char* buf_start,
                            const char* prefix_end, const char* buf_end);
 
@@ -184,7 +185,7 @@ ABSL_INTERNAL_ATOMIC_HOOK_ATTRIBUTES ABSL_DLL extern base_internal::AtomicHook<
 //
 // These functions are safe to call at any point during initialization; they do
 // not block or malloc, and are async-signal safe.
-void RegisterLogPrefixHook(LogPrefixHook func);
+void RegisterLogFilterAndPrefixHook(LogFilterAndPrefixHook func);
 void RegisterAbortHook(AbortHook func);
 void RegisterInternalLogFunction(InternalLogFunction func);