Truncate the download file name if it exceeds the filesystem limit.

base/sys_info_posix.cc

Index: base/sys_info_posix.cc
diff --git a/base/sys_info_posix.cc b/base/sys_info_posix.cc
index f2119cd7fdb538ebc34699088387aa2381e8cc4e..a7c72f21cc1ff5e1e6b60b1935f48990d570c78c 100644
--- a/base/sys_info_posix.cc
+++ b/base/sys_info_posix.cc
@@ -50,6 +50,24 @@ int64 SysInfo::AmountOfFreeDiskSpace(const FilePath& path) {
   return static_cast<int64>(stats.f_bavail) * stats.f_frsize;
 }
 
+// static
+int SysInfo::GetMaximumPathComponentLength(const FilePath& path) {
+  base::ThreadRestrictions::AssertIOAllowed();
+  if (!path.IsAbsolute())

[Mark Mentovai, 2013/02/08 18:14:02]

I don’t think this is relevant to the API. Maximum path component length of a
relative path can still be meaningful.

[kinaba, 2013/02/12 05:51:29]

Done.

+    return -1;
+
+  struct statvfs stats;
+  if (statvfs(path.value().c_str(), &stats) != 0) {

[Mark Mentovai, 2013/02/08 18:14:02]

On Mac OS X, you need to use pathconf(…, _PC_NAME_MAX) instead of statvfs if
you’re interested in f_namemax. statvfs returns a constant value for NAME_MAX
without considering the actual filesystem.

On Linux, pathconf(…, _PC_NAME_MAX) calls statfs under the hood, so pathconf
should be safe to use everywhere.

[kinaba, 2013/02/12 05:51:29]

Thanks for catching it! That greatly simplifies the code. Done.

+    return -1;
+  }
+#if defined(OS_ANDROID)
+  // Android uses statfs instead of statvfs. The field name differs.

[Mark Mentovai, 2013/02/08 18:14:02]

If you’re sticking with statfs for any code…

Hide this detail by way of a #define up above where statvfs is defined as statfs
for Android?

#define f_namemax f_namelen

[kinaba, 2013/02/12 05:51:29]

Done (using pathconf).

+  return static_cast<int>(stats.f_namelen);
+#else
+  return static_cast<int>(stats.f_namemax);
+#endif
+}
+
 #if !defined(OS_MACOSX) && !defined(OS_ANDROID)
 // static
 std::string SysInfo::OperatingSystemName() {