X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/a05599f12fd30388ee972ed2535d5297afe0c20b..40cdb71e715cf1c8e6d8201da307f992763f1654:/apt-pkg/contrib/fileutl.cc diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc index b5cdf782b..4240d9f49 100644 --- a/apt-pkg/contrib/fileutl.cc +++ b/apt-pkg/contrib/fileutl.cc @@ -1,6 +1,6 @@ // -*- mode: cpp; mode: fold -*- // Description /*{{{*/ -// $Id: fileutl.cc,v 1.15 1998/11/27 01:14:08 jgg Exp $ +// $Id: fileutl.cc,v 1.42 2002/09/14 05:29:22 jgg Exp $ /* ###################################################################### File Utilities @@ -8,22 +8,99 @@ 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 . + The exception is RunScripts() it is under the GPLv2 + ##################################################################### */ /*}}}*/ // Include Files /*{{{*/ -#ifdef __GNUG__ -#pragma implementation "apt-pkg/fileutl.h" -#endif #include #include +#include +#include + +#include + +#include +#include +#include #include +#include #include -#include #include +#include +#include +#include +#include +#include + /*}}}*/ + +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 /*{{{*/ @@ -35,18 +112,21 @@ bool CopyFile(FileFd &From,FileFd &To) return false; // Buffered copy between fds - unsigned char *Buf = new unsigned char[64000]; - long Size; - while ((Size = read(From.Fd(),Buf,64000)) > 0) + SPtrArray 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; } /*}}}*/ @@ -58,25 +138,46 @@ bool CopyFile(FileFd &From,FileFd &To) 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; } @@ -102,8 +203,11 @@ string SafeGetCWD() // 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; } /*}}}*/ @@ -121,16 +225,85 @@ string flNotDir(string File) /*}}}*/ // 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 File; + 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 /*{{{*/ // --------------------------------------------------------------------- /* */ @@ -158,26 +331,149 @@ void SetNonBlock(int Fd,bool Block) /*}}}*/ // WaitFd - Wait for a FD to become readable /*{{{*/ // --------------------------------------------------------------------- -/* This waits for a FD to become readable using select. It is usefull for - applications making use of non-blocking sockets. */ -bool WaitFd(int Fd) +/* 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); + } - if (select(Fd+1,&Set,0,0,0) <= 0) - return false; + // 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 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); + } + + + // 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::FileFd - Open a file /*{{{*/ +// 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) { @@ -186,9 +482,13 @@ FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms) 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); @@ -197,15 +497,19 @@ FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms) 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) - _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 /*{{{*/ @@ -219,16 +523,45 @@ FileFd::~FileFd() /*}}}*/ // 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 /*{{{*/ @@ -236,13 +569,29 @@ bool FileFd::Read(void *To,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 /*{{{*/ @@ -253,12 +602,51 @@ bool FileFd::Seek(unsigned long To) 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 /*{{{*/ // --------------------------------------------------------------------- /* */ @@ -278,13 +666,25 @@ bool FileFd::Close() 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; +} + /*}}}*/