Prototype implementation of zygotes.

Limitations that need addressing still:
- Doesn't forcibly terminate children that should have exited but haven't

Enable with env var ENABLE_ZYGOTE_MANAGER=1.

BUG=11841
TEST=
start the browser, then make chrome and all .pak files unreadable; or alternately, start an installed browser, and uninstall the browser while it's running.  Then create a new tab and browse to two new sites. 

Here's an example script to hide and unhide the .pak files (note: do not move the directory they're in, that doesn't work):

#!/bin/sh
chmod_all() {
   chmod $1 sconsbuild/Debug/chrome
   for path in . locales obj/chrome/app/intermediate/repack obj/global_intermediate/* themes
   do
     chmod $1 sconsbuild/Debug/$path/*.pak
   done
}
case $1 in
hide) chmod_all 000 ;;
show) chmod_all 755 ;;
esac


Review URL: http://codereview.chromium.org/115773

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@17840 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 24 insertions, 0 deletions

diff --git a/base/logging.cc b/base/logging.cc
index 7420883..b6aa730 100644
--- a/base/logging.cc
+++ b/base/logging.cc
@@ -19,9 +19,12 @@ typedef HANDLE MutexHandle;
 #endif
 
 #if defined(OS_POSIX)
+#include <fcntl.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <unistd.h>
 #define MAX_PATH PATH_MAX
 typedef FILE* FileHandle;
@@ -37,6 +40,7 @@ typedef pthread_mutex_t* MutexHandle;
 #include "base/command_line.h"
 #include "base/debug_util.h"
 #include "base/lock_impl.h"
+#include "base/reserved_file_descriptors.h"
 #include "base/string_piece.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
@@ -205,7 +209,17 @@ bool InitializeLogFileHandle() {
     }
     SetFilePointer(log_file, 0, 0, FILE_END);
 #elif defined(OS_POSIX)
+    // Reserve global fd slots.
+    int reserved_fds[kReservedFds];
+    for (int i=0; i < kReservedFds; i++)
+      reserved_fds[i] = open("/dev/null", O_RDONLY, 0);
+
     log_file = fopen(log_file_name->c_str(), "a");
+
+    // Release the reserved fds.
+    for (int i=0; i < kReservedFds; i++)
+      close(reserved_fds[i]);
+
     if (log_file == NULL)
       return false;
 #endif
@@ -214,6 +228,16 @@ bool InitializeLogFileHandle() {
   return true;
 }
 
+#if defined(OS_LINUX)
+int GetLoggingFileDescriptor() {
+  // No locking needed, since this is only called by the zygote server,
+  // which is single-threaded.
+  if (log_file)
+    return fileno(log_file);
+  return -1;
+}
+#endif
+
 void InitLogMutex() {
 #if defined(OS_WIN)
   if (!log_mutex) {