Localize strings, speeds.

ui/base/text/bytes_formatting.cc

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/base/text/bytes_formatting.h"
+
+#include "base/i18n/number_formatting.h"
+#include "base/logging.h"
+#include "base/string_util.h"
+#include "base/utf_string_conversions.h"
+#include "grit/app_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+
+namespace ui {
+
+namespace {
+
+// Byte suffix string constants. These both must match the DataUnits enum.
+const int kByteStrings[] = {
+  IDS_APP_BYTES,
+  IDS_APP_KILOBYTES,
+  IDS_APP_MEGABYTES,
+  IDS_APP_GIGABYTES,
+  IDS_APP_TERABYTES,
+  IDS_APP_PETABYTES
+};
+
+const int kSpeedStrings[] = {
+  IDS_APP_BYTES_PER_SECOND,
+  IDS_APP_KILOBYTES_PER_SECOND,
+  IDS_APP_MEGABYTES_PER_SECOND,
+  IDS_APP_GIGABYTES_PER_SECOND,
+  IDS_APP_TERABYTES_PER_SECOND,
+  IDS_APP_PETABYTES_PER_SECOND
+};
+
+string16 FormatBytesInternal(int64 bytes,
+                             DataUnits units,
+                             bool show_units,
+                             const int* const suffix) {
+  if (bytes < 0) {
+    NOTREACHED() << "Negative bytes value";
+    return string16();
+  }
+
+  if (units == DATA_UNITS_NATURAL)
+    units = GetByteDisplayUnits(bytes);
+  DCHECK(units >= DATA_UNITS_BYTE && units <= DATA_UNITS_PEBIBYTE);
+
+  // Put the quantity in the right units.
+  double unit_amount = static_cast<double>(bytes);
+  for (int i = 0; i < units; ++i)
+    unit_amount /= 1024.0;
+
+  int fractional_digits = 0;
+  if (bytes != 0 && units != DATA_UNITS_BYTE && unit_amount < 100)
+    fractional_digits = 1;
+
+  string16 result = base::FormatDouble(unit_amount, fractional_digits);
+
+  if (show_units)
+    result = l10n_util::GetStringFUTF16(suffix[units], result);

[jungshik at Google, 2011/06/22 00:35:01]

FYI: When plural format is used later (not now) for 'bytes',  'bytes' case has
to be special-cased to use ICU's PluralFormat API
(http://icu-project.org/apiref/icu4c/classPluralFormat.html ) because suffix
changes forms depending on the number. It might be possible to use ICU's generic
MessageFormat API for all the cases, but it seems unnecessary here.  

[Avi (use Gerrit), 2011/06/22 16:48:25]

Moving back to "B" for now will fix this. BTW, "bytes" is broken even in
English; I don't know what I was thinking.

+
+  return result;
+}
+
+}  // namespace
+
+DataUnits GetByteDisplayUnits(int64 bytes) {
+  // The byte thresholds at which we display amounts. A byte count is displayed
+  // in unit U when kUnitThresholds[U] <= bytes < kUnitThresholds[U+1].
+  // This must match the DataUnits enum.
+  static const int64 kUnitThresholds[] = {
+    0,                // DATA_UNITS_BYTE,
+    3 * (1LL << 10),  // DATA_UNITS_KIBIBYTE,
+    2 * (1LL << 20),  // DATA_UNITS_MEBIBYTE,
+    1LL << 30,        // DATA_UNITS_GIBIBYTE,
+    1LL << 40,        // DATA_UNITS_TEBIBYTE,
+    1LL << 50         // DATA_UNITS_PEBIBYTE,
+  };
+
+  if (bytes < 0) {
+    NOTREACHED() << "Negative bytes value";
+    return DATA_UNITS_BYTE;
+  }
+
+  int unit_index = arraysize(kUnitThresholds);
+  while (--unit_index > 0) {
+    if (bytes >= kUnitThresholds[unit_index])
+      break;
+  }
+
+  DCHECK(unit_index >= DATA_UNITS_BYTE && unit_index <= DATA_UNITS_PEBIBYTE);
+  return DataUnits(unit_index);
+}
+
+string16 FormatBytes(int64 bytes, DataUnits units, bool show_units) {
+  return FormatBytesInternal(bytes, units, show_units, kByteStrings);
+}
+
+string16 FormatSpeed(int64 bytes, DataUnits units, bool show_units) {
+  return FormatBytesInternal(bytes, units, show_units, kSpeedStrings);
+}
+
+}  // namespace ui