X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/0a8a80e58374771acc225fe1e08ed8e0fe0016cc..67a51bcc96e3e09528ce0b5841f93f511ed1e44f:/apt-pkg/contrib/fileutl.cc diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc index 3d5c4686b..ddb07532d 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 1.11 1998/10/22 04:56:47 jgg Exp $ +// $Id: fileutl.cc,v 1.31 1999/09/30 06:30:34 jgg Exp $ /* ###################################################################### File Utilities @@ -24,26 +24,37 @@ #include #include #include +#include +#include +#include +#include /*}}}*/ // 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) + unsigned long Size = From.Size(); + while (Size != 0) { - if (To.Write(Buf,Size) == false) + unsigned long ToRead = Size; + if (Size > 64000) + ToRead = 64000; + + if (From.Read(Buf,ToRead) == false || + To.Write(Buf,ToRead) == false) { delete [] Buf; return false; } + + Size -= ToRead; } delete [] Buf; @@ -68,12 +79,17 @@ int GetLock(string File,bool Errors) // 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 true; + } if (Errors == true) _error->Errno("open","Could not get lock %s",File.c_str()); close(FD); @@ -102,8 +118,11 @@ 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; } /*}}}*/ @@ -119,6 +138,57 @@ string flNotDir(string File) return string(File,Res,Res - File.length()); } /*}}}*/ +// flNotFile - Strip the file from the directory name /*{{{*/ +// --------------------------------------------------------------------- +/* */ +string flNotFile(string File) +{ + string::size_type Res = File.rfind('/'); + if (Res == string::npos) + return File; + Res++; + return string(File,0,Res); +} + /*}}}*/ +// 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; + } +} + /*}}}*/ // SetCloseExec - Set the close on exec flag /*{{{*/ // --------------------------------------------------------------------- /* */ @@ -147,25 +217,126 @@ 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) + 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. */ +int 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); + + // Close all of our FDs - just in case + for (int K = 3; K != 40; K++) + fcntl(K,F_SETFD,FD_CLOEXEC); + } + + return Process; +} + /*}}}*/ +// ExecWait - Fancy waitpid /*{{{*/ +// --------------------------------------------------------------------- +/* Waits for the given sub process. If Reap is set the no errors are + generated. Otherwise a failed subprocess will generate a proper descriptive + message */ +bool ExecWait(int 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 && WTERMSIG(Status) == SIGSEGV) + return _error->Error("Sub-process %s recieved 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::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) { @@ -174,9 +345,13 @@ 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 (stat(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); @@ -184,19 +359,15 @@ FileFd::FileFd(string FileName,OpenMode Mode, unsigned long Perms) 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; + 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 /*{{{*/ @@ -210,30 +381,70 @@ 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,bool AllowEof) { - if (read(iFd,To,Size) != (signed)Size) + int Res; + errno = 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; + } + while (Res > 0 && Size > 0); + + if (Size == 0) + return true; + + // Eof handling + if (AllowEof == true) + { + Flags |= HitEof; + return true; + } + + Flags |= Fail; + return _error->Error("read, still have %u 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 %u to write but couldn't",Size); } /*}}}*/ // FileFd::Seek - Seek in the file /*{{{*/ @@ -250,6 +461,45 @@ bool FileFd::Seek(unsigned long 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 %u",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 %u",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 /*{{{*/ // --------------------------------------------------------------------- /* */