Bug 1790873 - Move printf_stderr() to mozglue so it can be used within js/src r=glandium,nika

Differential Revision: https://phabricator.services.mozilla.com/D157354

Author: hotsphink

config/check_spidermonkey_style.py

@@ -69,6 +69,7 @@
         "jit/LIROpsGenerated.h",  # generated in $OBJDIR
         "jit/MIROpsGenerated.h",  # generated in $OBJDIR
         "js/ProfilingCategoryList.h",  # comes from mozglue/baseprofiler
+        "mozilla/glue/Debug.h",  # comes from mozglue/misc, shadowed by <mozilla/Debug.h>
         "jscustomallocator.h",  # provided by embedders;  allowed to be missing
         "js-config.h",  # generated in $OBJDIR
         "fdlibm.h",  # fdlibm

config/check_vanilla_allocations.py

@@ -147,6 +147,10 @@ def main():
         "Decimal.o",
         # Ignore use of std::string in regexp AST debug output.
         "regexp-ast.o",
+        # mozglue/misc/Debug.cpp contains a call to `printf_stderr("%s", aStr.str().c_str())`
+        # where `aStr` is a `std::stringstream`. In inlined opt builds, this calls
+        # `operator new()` and `operator delete` for a temporary.
+        "Debug.o",
     ]
     all_ignored_files = set((f, 1) for f in ignored_files)
 

mozglue/misc/Debug.cpp

@@ -0,0 +1,123 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/glue/Debug.h"
+#include "mozilla/Fuzzing.h"
+#include "mozilla/Sprintf.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#ifdef XP_WIN
+#  include <io.h>
+#  include <windows.h>
+#endif
+
+#ifdef ANDROID
+#  include <android/log.h>
+#endif
+
+#ifndef ANDROID
+static void vprintf_stderr_buffered(const char* aFmt, va_list aArgs) {
+  // Avoid interleaving by writing to an on-stack buffer and then writing in one
+  // go with fputs, as long as the output fits into the buffer.
+  char buffer[1024];
+  va_list argsCpy;
+  va_copy(argsCpy, aArgs);
+  int n = VsprintfLiteral(buffer, aFmt, aArgs);
+  if (n < int(sizeof(buffer))) {
+    fputs(buffer, stderr);
+  } else {
+    // Message too long for buffer. Just print it, not worrying about
+    // interleaving. (We could malloc, but the underlying write() syscall could
+    // get interleaved if the output is too big anyway.)
+    vfprintf(stderr, aFmt, argsCpy);
+  }
+  va_end(argsCpy);
+  fflush(stderr);
+}
+#endif
+
+#if defined(XP_WIN)
+MFBT_API void vprintf_stderr(const char* aFmt, va_list aArgs) {
+  if (IsDebuggerPresent()) {
+    int lengthNeeded = _vscprintf(aFmt, aArgs);
+    if (lengthNeeded) {
+      lengthNeeded++;
+      auto buf = mozilla::MakeUnique<char[]>(lengthNeeded);
+      if (buf) {
+        va_list argsCpy;
+        va_copy(argsCpy, aArgs);
+        vsnprintf(buf.get(), lengthNeeded, aFmt, argsCpy);
+        buf[lengthNeeded - 1] = '\0';
+        va_end(argsCpy);
+        OutputDebugStringA(buf.get());
+      }
+    }
+  }
+
+  vprintf_stderr_buffered(aFmt, aArgs);
+}
+
+#elif defined(ANDROID)
+MFBT_API void vprintf_stderr(const char* aFmt, va_list aArgs) {
+  __android_log_vprint(ANDROID_LOG_INFO, "Gecko", aFmt, aArgs);
+}
+#elif defined(FUZZING_SNAPSHOT)
+MFBT_API void vprintf_stderr(const char* aFmt, va_list aArgs) {
+  if (nyx_puts) {
+    auto msgbuf = mozilla::Vsmprintf(aFmt, aArgs);
+    nyx_puts(msgbuf.get());
+  } else {
+    vprintf_stderr_buffered(aFmt, aArgs);
+  }
+}
+#else
+MFBT_API void vprintf_stderr(const char* aFmt, va_list aArgs) {
+  vprintf_stderr_buffered(aFmt, aArgs);
+}
+#endif
+
+MFBT_API void printf_stderr(const char* aFmt, ...) {
+  va_list args;
+  va_start(args, aFmt);
+  vprintf_stderr(aFmt, args);
+  va_end(args);
+}
+
+MFBT_API void fprintf_stderr(FILE* aFile, const char* aFmt, ...) {
+  va_list args;
+  va_start(args, aFmt);
+  if (aFile == stderr) {
+    vprintf_stderr(aFmt, args);
+  } else {
+    vfprintf(aFile, aFmt, args);
+  }
+  va_end(args);
+}
+
+MFBT_API void print_stderr(std::stringstream& aStr) {
+#if defined(ANDROID)
+  // On Android logcat output is truncated to 1024 chars per line, and
+  // we usually use std::stringstream to build up giant multi-line gobs
+  // of output. So to avoid the truncation we find the newlines and
+  // print the lines individually.
+  std::string line;
+  while (std::getline(aStr, line)) {
+    printf_stderr("%s\n", line.c_str());
+  }
+#else
+  printf_stderr("%s", aStr.str().c_str());
+#endif
+}
+
+MFBT_API void fprint_stderr(FILE* aFile, std::stringstream& aStr) {
+  if (aFile == stderr) {
+    print_stderr(aStr);
+  } else {
+    fprintf_stderr(aFile, "%s", aStr.str().c_str());
+  }
+}

mozglue/misc/Debug.h

@@ -7,6 +7,12 @@
 #ifndef mozilla_glue_Debug_h
 #define mozilla_glue_Debug_h
 
+#include "mozilla/Attributes.h"  // For MOZ_FORMAT_PRINTF
+#include "mozilla/Types.h"       // For MFBT_API
+
+#include <cstdarg>
+#include <sstream>
+
 /* This header file intends to supply debugging utilities for use in code
  * that cannot use XPCOM debugging facilities like nsDebug.h.
  * e.g. mozglue, browser/app
@@ -15,52 +21,53 @@
  * care; avoid including from header files.
  */
 
-#include <io.h>
-#if defined(XP_WIN)
-#  include <windows.h>
-#endif  // defined(XP_WIN)
-#include "mozilla/Attributes.h"
-#include "mozilla/Sprintf.h"
-
-#if defined(MOZILLA_INTERNAL_API)
-#  error Do not include this file from XUL sources.
-#endif
-
-// Though this is a separate implementation than nsDebug's, we want to make the
-// declarations compatible to avoid confusing the linker if both headers are
-// included.
 #ifdef __cplusplus
 extern "C" {
 #endif  // __cplusplus
 
-void printf_stderr(const char* fmt, ...) MOZ_FORMAT_PRINTF(1, 2);
-inline void printf_stderr(const char* fmt, ...) {
-#if defined(XP_WIN)
-  if (IsDebuggerPresent()) {
-    char buf[2048];
-    va_list args;
-    va_start(args, fmt);
-    VsprintfLiteral(buf, fmt, args);
-    va_end(args);
-    OutputDebugStringA(buf);
-  }
-#endif  // defined(XP_WIN)
-
-  // stderr is unbuffered by default so we open a new FILE (which is buffered)
-  // so that calls to printf_stderr are not as likely to get mixed together.
-  int fd = _fileno(stderr);
-  if (fd == -2) return;
+/**
+ * printf_stderr(...) is much like fprintf(stderr, ...), except that:
+ *  - on Android and Firefox OS, *instead* of printing to stderr, it
+ *    prints to logcat.  (Newlines in the string lead to multiple lines
+ *    of logcat, but each function call implicitly completes a line even
+ *    if the string does not end with a newline.)
+ *  - on Windows, if a debugger is present, it calls OutputDebugString
+ *    in *addition* to writing to stderr
+ */
+MFBT_API void printf_stderr(const char* aFmt, ...) MOZ_FORMAT_PRINTF(1, 2);
 
-  FILE* fp = _fdopen(_dup(fd), "a");
-  if (!fp) return;
+/**
+ * Same as printf_stderr, but taking va_list instead of varargs
+ */
+MFBT_API void vprintf_stderr(const char* aFmt, va_list aArgs)
+    MOZ_FORMAT_PRINTF(1, 0);
 
-  va_list args;
-  va_start(args, fmt);
-  vfprintf(fp, fmt, args);
-  va_end(args);
+/**
+ * fprintf_stderr is like fprintf, except that if its file argument
+ * is stderr, it invokes printf_stderr instead.
+ *
+ * This is useful for general debugging code that logs information to a
+ * file, but that you would like to be useful on Android and Firefox OS.
+ * If you use fprintf_stderr instead of fprintf in such debugging code,
+ * then callers can pass stderr to get logging that works on Android and
+ * Firefox OS (and also the other side-effects of using printf_stderr).
+ *
+ * Code that is structured this way needs to be careful not to split a
+ * line of output across multiple calls to fprintf_stderr, since doing
+ * so will cause it to appear in multiple lines in logcat output.
+ * (Producing multiple lines at once is fine.)
+ */
+MFBT_API void fprintf_stderr(FILE* aFile, const char* aFmt, ...)
+    MOZ_FORMAT_PRINTF(2, 3);
 
-  fclose(fp);
-}
+/*
+ * print_stderr and fprint_stderr are like printf_stderr and fprintf_stderr,
+ * except they deal with Android logcat line length limitations. They do this
+ * by printing individual lines out of the provided stringstream using separate
+ * calls to logcat.
+ */
+MFBT_API void print_stderr(std::stringstream& aStr);
+MFBT_API void fprint_stderr(FILE* aFile, std::stringstream& aStr);
 
 #ifdef __cplusplus
 }

mozglue/misc/moz.build

@@ -43,6 +43,7 @@ if CONFIG["OS_ARCH"] == "WINNT":
 SOURCES += [
     "AutoProfilerLabel.cpp",
     "AwakeTimeStamp.cpp",
+    "Debug.cpp",
     "MmapFaultHandler.cpp",
     "Printf.cpp",
     "SIMD.cpp",

xpcom/base/nsCRTGlue.cpp

@@ -19,11 +19,6 @@
 #ifdef XP_WIN
 #  include <io.h>
 #  include <windows.h>
-#  include "mozilla/UniquePtr.h"
-#endif
-
-#ifdef ANDROID
-#  include <android/log.h>
 #endif
 
 #ifdef FUZZING_SNAPSHOT
@@ -229,105 +224,3 @@ void NS_MakeRandomString(char* aBuf, int32_t aBufLen) {
 }
 
 #endif
-
-#ifndef ANDROID
-void vprintf_stderr_buffered(const char* aFmt, va_list aArgs) {
-  // Avoid interleaving by writing to an on-stack buffer and then writing in one
-  // go with fputs, as long as the output fits into the buffer.
-  char buffer[1024];
-  va_list argsCpy;
-  va_copy(argsCpy, aArgs);
-  int n = VsprintfLiteral(buffer, aFmt, aArgs);
-  if (n < sizeof(buffer)) {
-    fputs(buffer, stderr);
-  } else {
-    // Message too long for buffer. Just print it, not worrying about
-    // interleaving. (We could malloc, but the underlying write() syscall could
-    // get interleaved if the output is too big anyway.)
-    vfprintf(stderr, aFmt, argsCpy);
-  }
-  va_end(argsCpy);
-  fflush(stderr);
-}
-#endif
-
-#if defined(XP_WIN)
-void vprintf_stderr(const char* aFmt, va_list aArgs) {
-  if (IsDebuggerPresent()) {
-    int lengthNeeded = _vscprintf(aFmt, aArgs);
-    if (lengthNeeded) {
-      lengthNeeded++;
-      auto buf = MakeUnique<char[]>(lengthNeeded);
-      if (buf) {
-        va_list argsCpy;
-        va_copy(argsCpy, aArgs);
-        vsnprintf(buf.get(), lengthNeeded, aFmt, argsCpy);
-        buf[lengthNeeded - 1] = '\0';
-        va_end(argsCpy);
-        OutputDebugStringA(buf.get());
-      }
-    }
-  }
-
-  vprintf_stderr_buffered(aFmt, aArgs);
-}
-
-#elif defined(ANDROID)
-void vprintf_stderr(const char* aFmt, va_list aArgs) {
-  __android_log_vprint(ANDROID_LOG_INFO, "Gecko", aFmt, aArgs);
-}
-#elif defined(FUZZING_SNAPSHOT)
-void vprintf_stderr(const char* aFmt, va_list aArgs) {
-  if (nyx_puts) {
-    auto msgbuf = mozilla::Vsmprintf(aFmt, aArgs);
-    nyx_puts(msgbuf.get());
-  } else {
-    vprintf_stderr_buffered(aFmt, aArgs);
-  }
-}
-#else
-void vprintf_stderr(const char* aFmt, va_list aArgs) {
-  vprintf_stderr_buffered(aFmt, aArgs);
-}
-#endif
-
-void printf_stderr(const char* aFmt, ...) {
-  va_list args;
-  va_start(args, aFmt);
-  vprintf_stderr(aFmt, args);
-  va_end(args);
-}
-
-void fprintf_stderr(FILE* aFile, const char* aFmt, ...) {
-  va_list args;
-  va_start(args, aFmt);
-  if (aFile == stderr) {
-    vprintf_stderr(aFmt, args);
-  } else {
-    vfprintf(aFile, aFmt, args);
-  }
-  va_end(args);
-}
-
-void print_stderr(std::stringstream& aStr) {
-#if defined(ANDROID)
-  // On Android logcat output is truncated to 1024 chars per line, and
-  // we usually use std::stringstream to build up giant multi-line gobs
-  // of output. So to avoid the truncation we find the newlines and
-  // print the lines individually.
-  std::string line;
-  while (std::getline(aStr, line)) {
-    printf_stderr("%s\n", line.c_str());
-  }
-#else
-  printf_stderr("%s", aStr.str().c_str());
-#endif
-}
-
-void fprint_stderr(FILE* aFile, std::stringstream& aStr) {
-  if (aFile == stderr) {
-    print_stderr(aStr);
-  } else {
-    fprintf_stderr(aFile, "%s", aStr.str().c_str());
-  }
-}