Use a steady clock source for progress reporting

Clock changes while apt is running can result in strange reports
confusing (and amusing) users. Sadly, to keep the ABI for now the
code is a bit more ugly than it would need to be.

1 files changed, 38 insertions, 32 deletions

diff --git a/ftparchive/apt-ftparchive.cc b/ftparchive/apt-ftparchive.cc
index a3fdf2391..077701cc0 100644
--- a/ftparchive/apt-ftparchive.cc
+++ b/ftparchive/apt-ftparchive.cc
@@ -23,6 +23,7 @@
 #include <apt-private/private-output.h>
 
 #include <algorithm>
+#include <chrono>
 #include <climits>
 #include <functional>
 #include <iostream>
@@ -33,6 +34,7 @@
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <time.h>
+#include <math.h>
 
 #include "apt-ftparchive.h"
 #include "cachedb.h"
@@ -46,6 +48,15 @@
 using namespace std;
 unsigned Quiet = 0;
 
+static struct timeval GetTimevalFromSteadyClock()			/*{{{*/
+{
+   auto const Time = std::chrono::steady_clock::now().time_since_epoch();
+   auto const Time_sec = std::chrono::duration_cast<std::chrono::seconds>(Time);
+   auto const Time_usec = std::chrono::duration_cast<std::chrono::microseconds>(Time - Time_sec);
+   return { Time_sec.count(), Time_usec.count() };
+}
+									/*}}}*/
+
 // struct PackageMap - List of all package files in the config file	/*{{{*/
 // ---------------------------------------------------------------------
 /* */
@@ -173,9 +184,8 @@ bool PackageMap::GenPackages(Configuration &Setup,struct CacheDB::Stats &Stats)
    string OverrideDir = Setup.FindDir("Dir::OverrideDir");
    string CacheDir = Setup.FindDir("Dir::CacheDir");
 
-   struct timeval StartTime;
-   gettimeofday(&StartTime,0);   
-   
+   struct timeval StartTime = GetTimevalFromSteadyClock();
+
    PkgDone = true;
    
    // Create a package writer object.
@@ -232,15 +242,15 @@ bool PackageMap::GenPackages(Configuration &Setup,struct CacheDB::Stats &Stats)
    else
       c0out << ' ';
    
-   struct timeval NewTime;
-   gettimeofday(&NewTime,0);
-   double Delta = NewTime.tv_sec - StartTime.tv_sec + 
-                  (NewTime.tv_usec - StartTime.tv_usec)/1000000.0;
+   struct timeval NewTime = GetTimevalFromSteadyClock();
+   std::chrono::duration<double> Delta =
+      std::chrono::seconds(NewTime.tv_sec - StartTime.tv_sec) +
+      std::chrono::microseconds(NewTime.tv_sec - StartTime.tv_usec);
 
    c0out << Packages.Stats.Packages << " files " <<
 /*      SizeToStr(Packages.Stats.MD5Bytes) << "B/" << */
       SizeToStr(Packages.Stats.Bytes) << "B " <<
-      TimeToStr((long)Delta) << endl;
+      TimeToStr(llround(Delta.count())) << endl;
 
    if(_config->FindB("APT::FTPArchive::ShowCacheMisses", false) == true)
      c0out << " Misses in Cache: " << Packages.Stats.Misses<< endl;
@@ -264,9 +274,7 @@ bool PackageMap::GenSources(Configuration &Setup,struct CacheDB::Stats &Stats)
    string OverrideDir = Setup.FindDir("Dir::OverrideDir");
    string CacheDir = Setup.FindDir("Dir::CacheDir");
 
-   struct timeval StartTime;
-   gettimeofday(&StartTime,0);   
-   
+   struct timeval StartTime = GetTimevalFromSteadyClock();
    SrcDone = true;
    
    // Create a package writer object.
@@ -320,13 +328,13 @@ bool PackageMap::GenSources(Configuration &Setup,struct CacheDB::Stats &Stats)
    else
       c0out << ' ';
    
-   struct timeval NewTime;
-   gettimeofday(&NewTime,0);
-   double Delta = NewTime.tv_sec - StartTime.tv_sec +
-                  (NewTime.tv_usec - StartTime.tv_usec)/1000000.0;
+   struct timeval NewTime = GetTimevalFromSteadyClock();
+   std::chrono::duration<double> Delta =
+      std::chrono::seconds(NewTime.tv_sec - StartTime.tv_sec) +
+      std::chrono::microseconds(NewTime.tv_sec - StartTime.tv_usec);
    
    c0out << Sources.Stats.Packages << " pkgs in " <<
-      TimeToStr((long)Delta) << endl;
+      TimeToStr(llround(Delta.count())) << endl;
 
    if(_config->FindB("APT::FTPArchive::ShowCacheMisses", false) == true)
      c0out << " Misses in Cache: " << Sources.Stats.Misses << endl;
@@ -356,10 +364,9 @@ bool PackageMap::GenContents(Configuration &Setup,
    string ArchiveDir = Setup.FindDir("Dir::ArchiveDir");
    string CacheDir = Setup.FindDir("Dir::CacheDir");
    string OverrideDir = Setup.FindDir("Dir::OverrideDir");
-   
-   struct timeval StartTime;
-   gettimeofday(&StartTime,0);   
-   
+
+   struct timeval StartTime = GetTimevalFromSteadyClock();
+
    // Create a package writer object.
    MultiCompress Comp(flCombine(ArchiveDir,this->Contents),
 		      CntCompress,Permissions);
@@ -437,17 +444,17 @@ bool PackageMap::GenContents(Configuration &Setup,
    else
       c0out << ' ';
    
-   struct timeval NewTime;
-   gettimeofday(&NewTime,0);   
-   double Delta = NewTime.tv_sec - StartTime.tv_sec + 
-                  (NewTime.tv_usec - StartTime.tv_usec)/1000000.0;
+   struct timeval NewTime = GetTimevalFromSteadyClock();
+   std::chrono::duration<double> Delta =
+      std::chrono::seconds(NewTime.tv_sec - StartTime.tv_sec) +
+      std::chrono::microseconds(NewTime.tv_sec - StartTime.tv_usec);
    
    if(_config->FindB("APT::FTPArchive::ShowCacheMisses", false) == true)
      c0out << " Misses in Cache: " << Contents.Stats.Misses<< endl;
 
    c0out << Contents.Stats.Packages << " files " <<
       SizeToStr(Contents.Stats.Bytes) << "B " <<
-      TimeToStr((long)Delta) << endl;
+      TimeToStr(llround(Delta.count())) << endl;
    
    return true;
 }
@@ -926,8 +933,7 @@ static bool Generate(CommandLine &CmdL)
    if (CmdL.FileSize() < 2)
       return ShowHelp(CmdL);
 
-   struct timeval StartTime;
-   gettimeofday(&StartTime,0);
+   struct timeval StartTime = GetTimevalFromSteadyClock();
    struct CacheDB::Stats Stats;
    
    // Read the configuration file.
@@ -964,12 +970,12 @@ static bool Generate(CommandLine &CmdL)
 	 return false;
       }
 
-   struct timeval NewTime;
-   gettimeofday(&NewTime,0);
-   double Delta = NewTime.tv_sec - StartTime.tv_sec +
-                  (NewTime.tv_usec - StartTime.tv_usec)/1000000.0;
+   struct timeval NewTime = GetTimevalFromSteadyClock();
+   std::chrono::duration<double> Delta =
+      std::chrono::seconds(NewTime.tv_sec - StartTime.tv_sec) +
+      std::chrono::microseconds(NewTime.tv_sec - StartTime.tv_usec);
    c1out << "Done. " << SizeToStr(Stats.Bytes) << "B in " << Stats.Packages
-         << " archives. Took " << TimeToStr((long)Delta) << endl;
+         << " archives. Took " << TimeToStr(llround(Delta.count())) << endl;
 
    UnloadTree(TransList);
    return true;