ppapi/tools/pepper_hash_for_uma.cc

   1 // Copyright (c) 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 //
   5 // This is a utility executable used for generating hashes for pepper
   6 // interfaces for inclusion in tools/metrics/histograms/histograms.xml. Every
   7 // interface-version pair must have a corresponding entry in the enum there.
   8 //
   9 // The hashing logic here must match the hashing logic at
  10 // ppapi/proxy/interface_list.cc.
  11 //
  12 // This utility can be used to generate a sorted list of hashes for all current
  13 // PPB* interfaces by running a script to generate the interface names, e.g.
  14 // $ grep -r "PPB_" ppapi/c | grep -o "\".*;[0-9]*\.[0-9]*\"" | tr '\n' ' '
  15 // and then invoking pepper_hash_for_uma on the list. The sorted output hashes
  16 // can be compared to tools/metrics/histograms/histograms.xml to determine if
  17 // any interfaces have been left out.
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22
  23 #include <algorithm>
  24 #include <vector>
  25
  26 #include "base/hash.h"
  27 #include "base/macros.h"
  28
  29 int main(int argc, char **argv) {
  30   if (argc < 2) {
  31     fprintf(stderr, "Usage: %s <interface1> <interface2> <...>\n", argv[0]);
  32     fprintf(stderr, "\n");
  33     fprintf(stderr, "Prints hashes for interface names.\n");
  34     fprintf(stderr, "Example: %s \"PPB_Var;1.1\" \"PPB_FileIO;1.2\"\n",
  35             argv[0]);
  36     return 1;
  37   }
  38   std::vector<std::pair<uint32, char*>> hashes;
  39   for (int i = 1; i < argc; i++) {
  40     uint32 data = base::Hash(argv[i], strlen(argv[i]));
  41
  42     // Strip off the signed bit because UMA doesn't support negative values,
  43     // but takes a signed int as input.
  44     int hash = static_cast<int>(data & 0x7fffffff);
  45     hashes.push_back(std::make_pair(hash, argv[i]));
  46   }
  47   std::sort(hashes.begin(), hashes.end());
  48   for (const auto& hash : hashes) {
  49     printf("<int value=\"%d\" label=\"%s\"/>\n", hash.first, hash.second);
  50   }
  51
  52   return 0;
  53 }