Apply patch from Sami Liedes <sliedes@cc.hut.fi> to avoid unecessary

[apt.git] / apt-pkg / contrib / fileutl.cc

diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc
index 43717da162a759441b9458d1c96c4a1cf6b169c5..a7de09c44d6d99f1d779053fc5fef341a63cbb55 100644 (file)
--- a/apt-pkg/contrib/fileutl.cc
+++ b/apt-pkg/contrib/fileutl.cc
@@ -1,6 +1,6 @@
 // -*- mode: cpp; mode: fold -*-
 // Description                                                         /*{{{*/
 // -*- mode: cpp; mode: fold -*-
 // Description                                                         /*{{{*/

-// $Id: fileutl.cc,v 1.27 1999/04/20 05:02:09 jgg Exp $
+// $Id: fileutl.cc,v 1.42 2002/09/14 05:29:22 jgg Exp $

 /* ######################################################################
    
    File Utilities
 /* ######################################################################
    
    File Utilities


@@ -8,25 +8,99 @@
    CopyFile - Buffered copy of a single file
    GetLock - dpkg compatible lock file manipulation (fcntl)
    
    CopyFile - Buffered copy of a single file
    GetLock - dpkg compatible lock file manipulation (fcntl)
    

-   This source is placed in the Public Domain, do with it what you will
-   It was originally written by Jason Gunthorpe.
+   Most of this source is placed in the Public Domain, do with it what 
+   you will
+   It was originally written by Jason Gunthorpe <jgg@debian.org>.

    
    

+   The exception is RunScripts() it is under the GPLv2
+

    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/

-#ifdef __GNUG__
-#pragma implementation "apt-pkg/fileutl.h"
-#endif 

 #include <apt-pkg/fileutl.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/fileutl.h>
 #include <apt-pkg/error.h>

+#include <apt-pkg/sptr.h>
+#include <apt-pkg/configuration.h>
+
+#include <apti18n.h>

 
 

+#include <cstdlib>
+#include <cstring>
+
+#include <iostream>

 #include <unistd.h>
 #include <unistd.h>

+#include <fcntl.h>

 #include <sys/stat.h>
 #include <sys/stat.h>

-#include <sys/fcntl.h>

 #include <sys/types.h>
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/time.h>

+#include <sys/wait.h>

 #include <signal.h>
 #include <errno.h>
 #include <signal.h>
 #include <errno.h>

+#include <set>
+                                                                       /*}}}*/
+
+using namespace std;
+
+// RunScripts - Run a set of scripts from a configuration subtree      /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool RunScripts(const char *Cnf)
+{
+   Configuration::Item const *Opts = _config->Tree(Cnf);
+   if (Opts == 0 || Opts->Child == 0)
+      return true;
+   Opts = Opts->Child;
+
+   // Fork for running the system calls
+   pid_t Child = ExecFork();
+   
+   // This is the child
+   if (Child == 0)
+   {
+      if (chdir("/tmp/") != 0)
+        _exit(100);
+        
+      unsigned int Count = 1;
+      for (; Opts != 0; Opts = Opts->Next, Count++)
+      {
+        if (Opts->Value.empty() == true)
+           continue;
+        
+        if (system(Opts->Value.c_str()) != 0)
+           _exit(100+Count);
+      }
+      _exit(0);
+   }      
+
+   // Wait for the child
+   int Status = 0;
+   while (waitpid(Child,&Status,0) != Child)
+   {
+      if (errno == EINTR)
+        continue;
+      return _error->Errno("waitpid","Couldn't wait for subprocess");
+   }
+
+   // Restore sig int/quit
+   signal(SIGQUIT,SIG_DFL);
+   signal(SIGINT,SIG_DFL);   
+
+   // Check for an error code.
+   if (WIFEXITED(Status) == 0 || WEXITSTATUS(Status) != 0)
+   {
+      unsigned int Count = WEXITSTATUS(Status);
+      if (Count > 100)
+      {
+        Count -= 100;
+        for (; Opts != 0 && Count != 1; Opts = Opts->Next, Count--);
+        _error->Error("Problem executing scripts %s '%s'",Cnf,Opts->Value.c_str());
+      }
+      
+      return _error->Error("Sub-process returned an error code");
+   }
+   
+   return true;
+}

                                                                        /*}}}*/
 
 // CopyFile - Buffered copy of a file                                  /*{{{*/
                                                                        /*}}}*/
 
 // CopyFile - Buffered copy of a file                                  /*{{{*/


@@ -38,7 +112,7 @@ bool CopyFile(FileFd &From,FileFd &To)
       return false;
    
    // Buffered copy between fds
       return false;
    
    // Buffered copy between fds

-   unsigned char *Buf = new unsigned char[64000];
+   SPtrArray<unsigned char> Buf = new unsigned char[64000];

    unsigned long Size = From.Size();
    while (Size != 0)
    {
    unsigned long Size = From.Size();
    while (Size != 0)
    {


@@ -48,15 +122,11 @@ bool CopyFile(FileFd &From,FileFd &To)
       
       if (From.Read(Buf,ToRead) == false || 
          To.Write(Buf,ToRead) == false)
       
       if (From.Read(Buf,ToRead) == false || 
          To.Write(Buf,ToRead) == false)

-      {
-        delete [] Buf;

         return false;
         return false;

-      }

       
       Size -= ToRead;
    }
 
       
       Size -= ToRead;
    }
 

-   delete [] Buf;

    return true;   
 }
                                                                        /*}}}*/
    return true;   
 }
                                                                        /*}}}*/


@@ -68,14 +138,27 @@ bool CopyFile(FileFd &From,FileFd &To)
    close at some time. */
 int GetLock(string File,bool Errors)
 {
    close at some time. */
 int GetLock(string File,bool Errors)
 {

-   int FD = open(File.c_str(),O_RDWR | O_CREAT | O_TRUNC,0640);
+   // GetLock() is used in aptitude on directories with public-write access
+   // Use O_NOFOLLOW here to prevent symlink traversal attacks
+   int FD = open(File.c_str(),O_RDWR | O_CREAT | O_NOFOLLOW,0640);

    if (FD < 0)
    {
    if (FD < 0)
    {

+      // Read only .. cant have locking problems there.
+      if (errno == EROFS)
+      {
+        _error->Warning(_("Not using locking for read only lock file %s"),File.c_str());
+        return dup(0);       // Need something for the caller to close
+      }
+      

       if (Errors == true)
       if (Errors == true)

-        _error->Errno("open","Could not open lock file %s",File.c_str());
+        _error->Errno("open",_("Could not open lock file %s"),File.c_str());
+
+      // Feh.. We do this to distinguish the lock vs open case..
+      errno = EPERM;

       return -1;
    }
       return -1;
    }

-   
+   SetCloseExec(FD,true);
+      

    // Aquire a write lock
    struct flock fl;
    fl.l_type = F_WRLCK;
    // Aquire a write lock
    struct flock fl;
    fl.l_type = F_WRLCK;


@@ -86,12 +169,15 @@ int GetLock(string File,bool Errors)
    {
       if (errno == ENOLCK)
       {
    {
       if (errno == ENOLCK)
       {

-        _error->Warning("Not using locking for nfs mounted lock file %s",File.c_str());
-        return true;
+        _error->Warning(_("Not using locking for nfs mounted lock file %s"),File.c_str());
+        return dup(0);       // Need something for the caller to close  

       }      
       if (Errors == true)
       }      
       if (Errors == true)

-        _error->Errno("open","Could not get lock %s",File.c_str());
+        _error->Errno("open",_("Could not get lock %s"),File.c_str());
+      
+      int Tmp = errno;

       close(FD);
       close(FD);

+      errno = Tmp;

       return -1;
    }
 
       return -1;
    }
 


@@ -139,16 +225,85 @@ string flNotDir(string File)
                                                                        /*}}}*/
 // flNotFile - Strip the file from the directory name                  /*{{{*/
 // ---------------------------------------------------------------------
                                                                        /*}}}*/
 // flNotFile - Strip the file from the directory name                  /*{{{*/
 // ---------------------------------------------------------------------

-/* */
+/* Result ends in a / */

 string flNotFile(string File)
 {
    string::size_type Res = File.rfind('/');
    if (Res == string::npos)
 string flNotFile(string File)
 {
    string::size_type Res = File.rfind('/');
    if (Res == string::npos)

-      return File;
+      return "./";

    Res++;
    return string(File,0,Res);
 }
                                                                        /*}}}*/
    Res++;
    return string(File,0,Res);
 }
                                                                        /*}}}*/

+// flExtension - Return the extension for the file                     /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+string flExtension(string File)
+{
+   string::size_type Res = File.rfind('.');
+   if (Res == string::npos)
+      return File;
+   Res++;
+   return string(File,Res,Res - File.length());
+}
+                                                                       /*}}}*/
+// flNoLink - If file is a symlink then deref it                       /*{{{*/
+// ---------------------------------------------------------------------
+/* If the name is not a link then the returned path is the input. */
+string flNoLink(string File)
+{
+   struct stat St;
+   if (lstat(File.c_str(),&St) != 0 || S_ISLNK(St.st_mode) == 0)
+      return File;
+   if (stat(File.c_str(),&St) != 0)
+      return File;
+   
+   /* Loop resolving the link. There is no need to limit the number of 
+      loops because the stat call above ensures that the symlink is not 
+      circular */
+   char Buffer[1024];
+   string NFile = File;
+   while (1)
+   {
+      // Read the link
+      int Res;
+      if ((Res = readlink(NFile.c_str(),Buffer,sizeof(Buffer))) <= 0 || 
+         (unsigned)Res >= sizeof(Buffer))
+         return File;
+      
+      // Append or replace the previous path
+      Buffer[Res] = 0;
+      if (Buffer[0] == '/')
+        NFile = Buffer;
+      else
+        NFile = flNotFile(NFile) + Buffer;
+      
+      // See if we are done
+      if (lstat(NFile.c_str(),&St) != 0)
+        return File;
+      if (S_ISLNK(St.st_mode) == 0)
+        return NFile;      
+   }   
+}
+                                                                       /*}}}*/
+// flCombine - Combine a file and a directory                          /*{{{*/
+// ---------------------------------------------------------------------
+/* If the file is an absolute path then it is just returned, otherwise
+   the directory is pre-pended to it. */
+string flCombine(string Dir,string File)
+{
+   if (File.empty() == true)
+      return string();
+   
+   if (File[0] == '/' || Dir.empty() == true)
+      return File;
+   if (File.length() >= 2 && File[0] == '.' && File[1] == '/')
+      return File;
+   if (Dir[Dir.length()-1] == '/')
+      return Dir + File;
+   return Dir + '/' + File;
+}
+                                                                       /*}}}*/

 // SetCloseExec - Set the close on exec flag                           /*{{{*/
 // ---------------------------------------------------------------------
 /* */
 // SetCloseExec - Set the close on exec flag                           /*{{{*/
 // ---------------------------------------------------------------------
 /* */


@@ -176,7 +331,7 @@ void SetNonBlock(int Fd,bool Block)
                                                                        /*}}}*/
 // WaitFd - Wait for a FD to become readable                           /*{{{*/
 // ---------------------------------------------------------------------
                                                                        /*}}}*/
 // WaitFd - Wait for a FD to become readable                           /*{{{*/
 // ---------------------------------------------------------------------

-/* This waits for a FD to become readable using select. It is usefull for
+/* This waits for a FD to become readable using select. It is useful for

    applications making use of non-blocking sockets. The timeout is 
    in seconds. */
 bool WaitFd(int Fd,bool write,unsigned long timeout)
    applications making use of non-blocking sockets. The timeout is 
    in seconds. */
 bool WaitFd(int Fd,bool write,unsigned long timeout)


@@ -220,7 +375,7 @@ bool WaitFd(int Fd,bool write,unsigned long timeout)
 /* This is used if you want to cleanse the environment for the forked 
    child, it fixes up the important signals and nukes all of the fds,
    otherwise acts like normal fork. */
 /* This is used if you want to cleanse the environment for the forked 
    child, it fixes up the important signals and nukes all of the fds,
    otherwise acts like normal fork. */

-int ExecFork()
+pid_t ExecFork()

 {
    // Fork off the process
    pid_t Process = fork();
 {
    // Fork off the process
    pid_t Process = fork();


@@ -240,21 +395,83 @@ int ExecFork()
       signal(SIGWINCH,SIG_DFL);
       signal(SIGCONT,SIG_DFL);
       signal(SIGTSTP,SIG_DFL);
       signal(SIGWINCH,SIG_DFL);
       signal(SIGCONT,SIG_DFL);
       signal(SIGTSTP,SIG_DFL);

-      
+
+      set<int> KeepFDs;
+      Configuration::Item const *Opts = _config->Tree("APT::Keep-Fds");
+      if (Opts != 0 && Opts->Child != 0)
+      {
+        Opts = Opts->Child;
+        for (; Opts != 0; Opts = Opts->Next)
+        {
+           if (Opts->Value.empty() == true)
+              continue;
+           int fd = atoi(Opts->Value.c_str());
+           KeepFDs.insert(fd);
+        }
+      }
+

       // Close all of our FDs - just in case
       for (int K = 3; K != 40; K++)
       // Close all of our FDs - just in case
       for (int K = 3; K != 40; K++)

-        fcntl(K,F_SETFD,FD_CLOEXEC);
+      {
+        if(KeepFDs.find(K) == KeepFDs.end())
+           fcntl(K,F_SETFD,FD_CLOEXEC);
+      }

    }
    
    return Process;
 }
                                                                        /*}}}*/
    }
    
    return Process;
 }
                                                                        /*}}}*/

+// ExecWait - Fancy waitpid                                            /*{{{*/
+// ---------------------------------------------------------------------
+/* Waits for the given sub process. If Reap is set then no errors are 
+   generated. Otherwise a failed subprocess will generate a proper descriptive
+   message */
+bool ExecWait(pid_t Pid,const char *Name,bool Reap)
+{
+   if (Pid <= 1)
+      return true;
+   
+   // Wait and collect the error code
+   int Status;
+   while (waitpid(Pid,&Status,0) != Pid)
+   {
+      if (errno == EINTR)
+        continue;
+
+      if (Reap == true)
+        return false;
+      
+      return _error->Error(_("Waited for %s but it wasn't there"),Name);
+   }

 
 

-// FileFd::FileFd - Open a file                                                /*{{{*/
+   
+   // Check for an error code.
+   if (WIFEXITED(Status) == 0 || WEXITSTATUS(Status) != 0)
+   {
+      if (Reap == true)
+        return false;
+      if (WIFSIGNALED(Status) != 0)
+        if( WTERMSIG(Status) == SIGSEGV)
+           return _error->Error(_("Sub-process %s received a segmentation fault."),Name);
+        else 
+           return _error->Error(_("Sub-process %s received signal %u."),Name, WTERMSIG(Status));
+
+      if (WIFEXITED(Status) != 0)
+        return _error->Error(_("Sub-process %s returned an error code (%u)"),Name,WEXITSTATUS(Status));
+      
+      return _error->Error(_("Sub-process %s exited unexpectedly"),Name);
+   }      
+   
+   return true;
+}
+                                                                       /*}}}*/
+
+// FileFd::Open - Open a file                                          /*{{{*/

 // ---------------------------------------------------------------------
 /* The most commonly used open mode combinations are given with Mode */
 // ---------------------------------------------------------------------
 /* The most commonly used open mode combinations are given with Mode */

-FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms)
+bool FileFd::Open(string FileName,OpenMode Mode, unsigned long Perms)

 {
 {

+   Close();

    Flags = AutoClose;
    switch (Mode)
    {
    Flags = AutoClose;
    switch (Mode)
    {


@@ -265,7 +482,7 @@ FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms)
       case WriteEmpty:
       {
         struct stat Buf;
       case WriteEmpty:
       {
         struct stat Buf;

-        if (stat(FileName.c_str(),&Buf) == 0 && S_ISLNK(Buf.st_mode))
+        if (lstat(FileName.c_str(),&Buf) == 0 && S_ISLNK(Buf.st_mode))

            unlink(FileName.c_str());
         iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_TRUNC,Perms);
         break;
            unlink(FileName.c_str());
         iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_TRUNC,Perms);
         break;


@@ -278,15 +495,19 @@ FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms)
       case WriteAny:
       iFd = open(FileName.c_str(),O_RDWR | O_CREAT,Perms);
       break;      
       case WriteAny:
       iFd = open(FileName.c_str(),O_RDWR | O_CREAT,Perms);
       break;      

+
+      case WriteTemp:
+      unlink(FileName.c_str());
+      iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_EXCL,Perms);
+      break;

    }  
 
    if (iFd < 0)
    }  
 
    if (iFd < 0)

-      _error->Errno("open","Could not open file %s",FileName.c_str());
-   else
-   {
-      this->FileName = FileName;
-      SetCloseExec(iFd,true);
-   }   
+      return _error->Errno("open",_("Could not open file %s"),FileName.c_str());
+   
+   this->FileName = FileName;
+   SetCloseExec(iFd,true);
+   return true;

 }
                                                                        /*}}}*/
 // FileFd::~File - Closes the file                                     /*{{{*/
 }
                                                                        /*}}}*/
 // FileFd::~File - Closes the file                                     /*{{{*/


@@ -302,10 +523,13 @@ FileFd::~FileFd()
 // ---------------------------------------------------------------------
 /* We are carefull to handle interruption by a signal while reading 
    gracefully. */
 // ---------------------------------------------------------------------
 /* We are carefull to handle interruption by a signal while reading 
    gracefully. */

-bool FileFd::Read(void *To,unsigned long Size)
+bool FileFd::Read(void *To,unsigned long Size,unsigned long *Actual)

 {
    int Res;
    errno = 0;
 {
    int Res;
    errno = 0;

+   if (Actual != 0)
+      *Actual = 0;
+   

    do
    {
       Res = read(iFd,To,Size);
    do
    {
       Res = read(iFd,To,Size);


@@ -314,19 +538,28 @@ bool FileFd::Read(void *To,unsigned long Size)
       if (Res < 0)
       {
         Flags |= Fail;
       if (Res < 0)
       {
         Flags |= Fail;

-        return _error->Errno("read","Read error");
+        return _error->Errno("read",_("Read error"));

       }
       
       To = (char *)To + Res;
       Size -= Res;
       }
       
       To = (char *)To + Res;
       Size -= Res;

+      if (Actual != 0)
+        *Actual += Res;

    }
    while (Res > 0 && Size > 0);
    
    if (Size == 0)
       return true;
    
    }
    while (Res > 0 && Size > 0);
    
    if (Size == 0)
       return true;
    

+   // Eof handling
+   if (Actual != 0)
+   {
+      Flags |= HitEof;
+      return true;
+   }
+   

    Flags |= Fail;
    Flags |= Fail;

-   return _error->Error("read, still have %u to read but none left",Size);
+   return _error->Error(_("read, still have %lu to read but none left"),Size);

 }
                                                                        /*}}}*/
 // FileFd::Write - Write to the file                                   /*{{{*/
 }
                                                                        /*}}}*/
 // FileFd::Write - Write to the file                                   /*{{{*/


@@ -344,7 +577,7 @@ bool FileFd::Write(const void *From,unsigned long Size)
       if (Res < 0)
       {
         Flags |= Fail;
       if (Res < 0)
       {
         Flags |= Fail;

-        return _error->Errno("write","Write error");
+        return _error->Errno("write",_("Write error"));

       }
       
       From = (char *)From + Res;
       }
       
       From = (char *)From + Res;


@@ -356,7 +589,7 @@ bool FileFd::Write(const void *From,unsigned long Size)
       return true;
    
    Flags |= Fail;
       return true;
    
    Flags |= Fail;

-   return _error->Error("write, still have %u to write but couldn't",Size);
+   return _error->Error(_("write, still have %lu to write but couldn't"),Size);

 }
                                                                        /*}}}*/
 // FileFd::Seek - Seek in the file                                     /*{{{*/
 }
                                                                        /*}}}*/
 // FileFd::Seek - Seek in the file                                     /*{{{*/


@@ -367,7 +600,21 @@ bool FileFd::Seek(unsigned long To)
    if (lseek(iFd,To,SEEK_SET) != (signed)To)
    {
       Flags |= Fail;
    if (lseek(iFd,To,SEEK_SET) != (signed)To)
    {
       Flags |= Fail;

-      return _error->Error("Unable to seek to %u",To);
+      return _error->Error("Unable to seek to %lu",To);
+   }
+   
+   return true;
+}
+                                                                       /*}}}*/
+// FileFd::Skip - Seek in the file                                     /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool FileFd::Skip(unsigned long Over)
+{
+   if (lseek(iFd,Over,SEEK_CUR) < 0)
+   {
+      Flags |= Fail;
+      return _error->Error("Unable to seek ahead %lu",Over);

    }
    
    return true;
    }
    
    return true;


@@ -381,7 +628,7 @@ bool FileFd::Truncate(unsigned long To)
    if (ftruncate(iFd,To) != 0)
    {
       Flags |= Fail;
    if (ftruncate(iFd,To) != 0)
    {
       Flags |= Fail;

-      return _error->Error("Unable to truncate to %u",To);
+      return _error->Error("Unable to truncate to %lu",To);

    }
    
    return true;
    }
    
    return true;


@@ -417,13 +664,25 @@ bool FileFd::Close()
    bool Res = true;
    if ((Flags & AutoClose) == AutoClose)
       if (iFd >= 0 && close(iFd) != 0)
    bool Res = true;
    if ((Flags & AutoClose) == AutoClose)
       if (iFd >= 0 && close(iFd) != 0)

-        Res &= _error->Errno("close","Problem closing the file");
+        Res &= _error->Errno("close",_("Problem closing the file"));

    iFd = -1;
    
    if ((Flags & Fail) == Fail && (Flags & DelOnFail) == DelOnFail &&
        FileName.empty() == false)
       if (unlink(FileName.c_str()) != 0)
    iFd = -1;
    
    if ((Flags & Fail) == Fail && (Flags & DelOnFail) == DelOnFail &&
        FileName.empty() == false)
       if (unlink(FileName.c_str()) != 0)

-        Res &= _error->Warning("unlnk","Problem unlinking the file");
+        Res &= _error->WarningE("unlnk",_("Problem unlinking the file"));

    return Res;
 }
                                                                        /*}}}*/
    return Res;
 }
                                                                        /*}}}*/

+// FileFd::Sync - Sync the file                                                /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool FileFd::Sync()
+{
+#ifdef _POSIX_SYNCHRONIZED_IO
+   if (fsync(iFd) != 0)
+      return _error->Errno("sync",_("Problem syncing the file"));
+#endif
+   return true;
+}
+                                                                       /*}}}*/