// -*- mode: cpp; mode: fold -*-
// Description /*{{{*/
-// $Id: fileutl.cc,v 1.8 1998/10/02 04:39:50 jgg Exp $
+// $Id: fileutl.cc,v 1.42 2002/09/14 05:29:22 jgg Exp $
/* ######################################################################
File Utilities
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 /*{{{*/
-#ifdef __GNUG__
-#pragma implementation "apt-pkg/fileutl.h"
-#endif
#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 <fcntl.h>
#include <sys/stat.h>
-#include <sys/fcntl.h>
#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/wait.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 /*{{{*/
// ---------------------------------------------------------------------
/* The caller is expected to set things so that failure causes erasure */
-bool CopyFile(FileFd From,FileFd To)
+bool CopyFile(FileFd &From,FileFd &To)
{
if (From.IsOpen() == false || To.IsOpen() == false)
return false;
// Buffered copy between fds
- unsigned char *Buf = new unsigned char[64000];
- long Size;
- while ((Size = read(From.Fd(),Buf,64000)) > 0)
+ SPtrArray<unsigned char> Buf = new unsigned char[64000];
+ unsigned long Size = From.Size();
+ while (Size != 0)
{
- if (To.Write(Buf,Size) == false)
- {
- delete [] Buf;
+ unsigned long ToRead = Size;
+ if (Size > 64000)
+ ToRead = 64000;
+
+ if (From.Read(Buf,ToRead) == false ||
+ To.Write(Buf,ToRead) == false)
return false;
- }
+
+ Size -= ToRead;
}
- delete [] Buf;
return true;
}
/*}}}*/
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)
{
+ // 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)
- _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;
}
-
+ SetCloseExec(FD,true);
+
// Aquire a write lock
struct flock fl;
- fl.l_type= F_WRLCK;
- fl.l_whence= SEEK_SET;
- fl.l_start= 0;
- fl.l_len= 1;
+ fl.l_type = F_WRLCK;
+ fl.l_whence = SEEK_SET;
+ fl.l_start = 0;
+ fl.l_len = 0;
if (fcntl(FD,F_SETLK,&fl) == -1)
{
+ if (errno == ENOLCK)
+ {
+ _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)
- _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);
+ errno = Tmp;
return -1;
}
// Stash the current dir.
char S[300];
S[0] = 0;
- if (getcwd(S,sizeof(S)) == 0)
+ if (getcwd(S,sizeof(S)-2) == 0)
return "/";
+ unsigned int Len = strlen(S);
+ S[Len] = '/';
+ S[Len+1] = 0;
return S;
}
/*}}}*/
return string(File,Res,Res - File.length());
}
/*}}}*/
+// 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)
+ return "./";
+ 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 /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void SetCloseExec(int Fd,bool Close)
+{
+ if (fcntl(Fd,F_SETFD,(Close == false)?0:FD_CLOEXEC) != 0)
+ {
+ cerr << "FATAL -> Could not set close on exec " << strerror(errno) << endl;
+ exit(100);
+ }
+}
+ /*}}}*/
+// SetNonBlock - Set the nonblocking flag /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+void SetNonBlock(int Fd,bool Block)
+{
+ int Flags = fcntl(Fd,F_GETFL) & (~O_NONBLOCK);
+ if (fcntl(Fd,F_SETFL,Flags | ((Block == false)?0:O_NONBLOCK)) != 0)
+ {
+ cerr << "FATAL -> Could not set non-blocking flag " << strerror(errno) << endl;
+ exit(100);
+ }
+}
+ /*}}}*/
+// WaitFd - Wait for a FD to become readable /*{{{*/
+// ---------------------------------------------------------------------
+/* 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)
+{
+ fd_set Set;
+ struct timeval tv;
+ FD_ZERO(&Set);
+ FD_SET(Fd,&Set);
+ tv.tv_sec = timeout;
+ tv.tv_usec = 0;
+ if (write == true)
+ {
+ int Res;
+ do
+ {
+ Res = select(Fd+1,0,&Set,0,(timeout != 0?&tv:0));
+ }
+ while (Res < 0 && errno == EINTR);
+
+ if (Res <= 0)
+ return false;
+ }
+ else
+ {
+ int Res;
+ do
+ {
+ Res = select(Fd+1,&Set,0,0,(timeout != 0?&tv:0));
+ }
+ while (Res < 0 && errno == EINTR);
+
+ if (Res <= 0)
+ return false;
+ }
+
+ return true;
+}
+ /*}}}*/
+// ExecFork - Magical fork that sanitizes the context before execing /*{{{*/
+// ---------------------------------------------------------------------
+/* 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. */
+pid_t ExecFork()
+{
+ // Fork off the process
+ pid_t Process = fork();
+ if (Process < 0)
+ {
+ cerr << "FATAL -> Failed to fork." << endl;
+ exit(100);
+ }
+
+ // Spawn the subprocess
+ if (Process == 0)
+ {
+ // Setup the signals
+ signal(SIGPIPE,SIG_DFL);
+ signal(SIGQUIT,SIG_DFL);
+ signal(SIGINT,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++)
+ {
+ if(KeepFDs.find(K) == KeepFDs.end())
+ fcntl(K,F_SETFD,FD_CLOEXEC);
+ }
+ }
+
+ 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 && WTERMSIG(Status) == SIGSEGV)
+ return _error->Error(_("Sub-process %s received a segmentation fault."),Name);
+
+ 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 */
-FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms)
+bool FileFd::Open(string FileName,OpenMode Mode, unsigned long Perms)
{
+ Close();
Flags = AutoClose;
switch (Mode)
{
break;
case WriteEmpty:
- unlink(FileName.c_str());
- iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_EXCL,Perms);
- break;
+ {
+ struct stat Buf;
+ 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;
+ }
case WriteExists:
iFd = open(FileName.c_str(),O_RDWR);
case WriteAny:
iFd = open(FileName.c_str(),O_RDWR | O_CREAT,Perms);
- break;
-
- // Dont use this in public directories
- case LockEmpty:
- iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_TRUNC,Perms);
+ break;
+
+ case WriteTemp:
+ unlink(FileName.c_str());
+ iFd = open(FileName.c_str(),O_RDWR | O_CREAT | O_EXCL,Perms);
break;
}
if (iFd < 0)
- _error->Errno("open","Could not open file %s",FileName.c_str());
- else
- this->FileName = FileName;
+ 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::Read - Read a bit of the file /*{{{*/
// ---------------------------------------------------------------------
-/* */
-bool FileFd::Read(void *To,unsigned long Size)
+/* We are carefull to handle interruption by a signal while reading
+ gracefully. */
+bool FileFd::Read(void *To,unsigned long Size,unsigned long *Actual)
{
- if (read(iFd,To,Size) != (signed)Size)
+ int Res;
+ errno = 0;
+ if (Actual != 0)
+ *Actual = 0;
+
+ do
{
- Flags |= Fail;
- return _error->Errno("read","Read error");
- }
+ Res = read(iFd,To,Size);
+ if (Res < 0 && errno == EINTR)
+ continue;
+ if (Res < 0)
+ {
+ Flags |= Fail;
+ return _error->Errno("read",_("Read error"));
+ }
- return true;
+ To = (char *)To + Res;
+ Size -= Res;
+ if (Actual != 0)
+ *Actual += Res;
+ }
+ while (Res > 0 && Size > 0);
+
+ if (Size == 0)
+ return true;
+
+ // Eof handling
+ if (Actual != 0)
+ {
+ Flags |= HitEof;
+ return true;
+ }
+
+ Flags |= Fail;
+ return _error->Error(_("read, still have %lu to read but none left"),Size);
}
/*}}}*/
// FileFd::Write - Write to the file /*{{{*/
// ---------------------------------------------------------------------
/* */
-bool FileFd::Write(void *From,unsigned long Size)
+bool FileFd::Write(const void *From,unsigned long Size)
{
- if (write(iFd,From,Size) != (signed)Size)
+ int Res;
+ errno = 0;
+ do
{
- Flags |= Fail;
- return _error->Errno("write","Write error");
+ Res = write(iFd,From,Size);
+ if (Res < 0 && errno == EINTR)
+ continue;
+ if (Res < 0)
+ {
+ Flags |= Fail;
+ return _error->Errno("write",_("Write error"));
+ }
+
+ From = (char *)From + Res;
+ Size -= Res;
}
+ while (Res > 0 && Size > 0);
- return true;
+ if (Size == 0)
+ return true;
+
+ Flags |= Fail;
+ return _error->Error(_("write, still have %lu to write but couldn't"),Size);
}
/*}}}*/
// FileFd::Seek - Seek in the file /*{{{*/
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;
+}
+ /*}}}*/
+// FileFd::Truncate - Truncate the file /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool FileFd::Truncate(unsigned long To)
+{
+ if (ftruncate(iFd,To) != 0)
+ {
+ Flags |= Fail;
+ return _error->Error("Unable to truncate to %lu",To);
+ }
+
+ return true;
+}
+ /*}}}*/
+// FileFd::Tell - Current seek position /*{{{*/
+// ---------------------------------------------------------------------
+/* */
+unsigned long FileFd::Tell()
+{
+ off_t Res = lseek(iFd,0,SEEK_CUR);
+ if (Res == (off_t)-1)
+ _error->Errno("lseek","Failed to determine the current file position");
+ return Res;
+}
+ /*}}}*/
// FileFd::Size - Return the size of the file /*{{{*/
// ---------------------------------------------------------------------
/* */
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)
- Res &= _error->Warning("unlnk","Problem unlinking the file");
+ Res &= _error->WarningE("unlnk",_("Problem unlinking the file"));
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;
+}
+ /*}}}*/
projects / apt.git / blobdiff