Adding upstream version 2.2.4.upstream/2.2.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 293 insertions, 0 deletions

diff --git a/apt-pkg/contrib/cdromutl.cc b/apt-pkg/contrib/cdromutl.cc
new file mode 100644
index 0000000..c0fe869
--- /dev/null
+++ b/apt-pkg/contrib/cdromutl.cc
@@ -0,0 +1,293 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+   
+   CDROM Utilities - Some functions to manipulate CDROM mounts.
+   
+   These are here for the cdrom method and apt-cdrom.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/cdromutl.h>
+#include <apt-pkg/configuration.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/hashes.h>
+#include <apt-pkg/strutl.h>
+
+#include <iostream>
+#include <string>
+#include <vector>
+#include <dirent.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/statvfs.h>
+#include <unistd.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+using std::string;
+
+// IsMounted - Returns true if the mount point is mounted		/*{{{*/
+// ---------------------------------------------------------------------
+/* This is a simple algorithm that should always work, we stat the mount point
+   and the '..' file in the mount point and see if they are on the same device.
+   By definition if they are the same then it is not mounted. This should 
+   account for symlinked mount points as well. */
+bool IsMounted(string &Path)
+{
+   if (Path.empty() == true)
+      return false;
+
+   // Need that trailing slash for directories
+   if (Path[Path.length() - 1] != '/')
+      Path += '/';
+
+   // if the path has a ".disk" directory we treat it as mounted
+   // this way even extracted copies of disks are recognized
+   if (DirectoryExists(Path + ".disk/") == true)
+      return true;
+
+   /* First we check if the path is actually mounted, we do this by
+      stating the path and the previous directory (careful of links!)
+      and comparing their device fields. */
+   struct stat Buf,Buf2;
+   if (stat(Path.c_str(),&Buf) != 0 || 
+       stat((Path + "../").c_str(),&Buf2) != 0)
+      return _error->Errno("stat",_("Unable to stat the mount point %s"),Path.c_str());
+
+   if (Buf.st_dev == Buf2.st_dev)
+      return false;
+   return true;
+}
+									/*}}}*/
+// UnmountCdrom - Unmount a cdrom					/*{{{*/
+// ---------------------------------------------------------------------
+/* Forking umount works much better than the umount syscall which can 
+   leave /etc/mtab inconsitant. We drop all messages this produces. */
+bool UnmountCdrom(string Path)
+{
+   // do not generate errors, even if the mountpoint does not exist
+   // the mountpoint might be auto-created by the mount command
+   // and a non-existing mountpoint is surely not mounted
+   _error->PushToStack();
+   bool const mounted = IsMounted(Path);
+   _error->RevertToStack();
+   if (mounted == false)
+      return true;
+
+   for (int i=0;i<3;i++)
+   {
+   
+      int Child = ExecFork();
+
+      // The child
+      if (Child == 0)
+      {
+	 // Make all the fds /dev/null
+	 int const null_fd = open("/dev/null",O_RDWR);
+	 for (int I = 0; I != 3; ++I)
+	    dup2(null_fd, I);
+
+	 if (_config->Exists("Acquire::cdrom::"+Path+"::UMount") == true)
+	 {
+	    if (system(_config->Find("Acquire::cdrom::"+Path+"::UMount").c_str()) != 0)
+	       _exit(100);
+	    _exit(0);	 	 
+	 }
+	 else
+	 {
+	    const char * const Args[] = {
+	       "umount",
+	       Path.c_str(),
+	       nullptr
+	    };
+	    execvp(Args[0], const_cast<char **>(Args));
+	    _exit(100);
+	 }
+      }
+
+      // if it can not be umounted, give it a bit more time
+      // this can happen when auto-mount magic or fs/cdrom prober attack
+      if (ExecWait(Child,"umount",true) == true)
+	 return true;
+      sleep(1);
+   }
+
+   return false;
+}
+									/*}}}*/
+// MountCdrom - Mount a cdrom						/*{{{*/
+// ---------------------------------------------------------------------
+/* We fork mount and drop all messages */
+bool MountCdrom(string Path, string DeviceName)
+{
+   // do not generate errors, even if the mountpoint does not exist
+   // the mountpoint might be auto-created by the mount command
+   _error->PushToStack();
+   bool const mounted = IsMounted(Path);
+   _error->RevertToStack();
+   if (mounted == true)
+      return true;
+
+   int Child = ExecFork();
+
+   // The child
+   if (Child == 0)
+   {
+      // Make all the fds /dev/null
+      int const null_fd = open("/dev/null",O_RDWR);
+      for (int I = 0; I != 3; ++I)
+	 dup2(null_fd, I);
+
+      if (_config->Exists("Acquire::cdrom::"+Path+"::Mount") == true)
+      {
+	 if (system(_config->Find("Acquire::cdrom::"+Path+"::Mount").c_str()) != 0)
+	    _exit(100);
+	 _exit(0);	 
+      }
+      else
+      {
+	 const char *Args[10];
+	 Args[0] = "mount";
+	 if (DeviceName == "") 
+	 {
+	    Args[1] = Path.c_str();
+	    Args[2] = 0;
+	 } else {
+	    Args[1] = DeviceName.c_str();
+	    Args[2] = Path.c_str();
+	    Args[3] = 0;
+	 }
+	 execvp(Args[0],(char **)Args);      
+	 _exit(100);
+      }      
+   }
+
+   // Wait for mount
+   return ExecWait(Child,"mount",true);
+}
+									/*}}}*/
+// IdentCdrom - Generate a unique string for this CD			/*{{{*/
+// ---------------------------------------------------------------------
+/* We convert everything we hash into a string, this prevents byte size/order
+   from effecting the outcome. */
+bool IdentCdrom(string CD,string &Res,unsigned int Version)
+{
+   Hashes Hash(Hashes::MD5SUM);
+   bool writable_media = false;
+
+   int dirfd = open(CD.c_str(), O_RDONLY | O_DIRECTORY | O_CLOEXEC);
+   if (dirfd == -1)
+      return _error->Errno("open",_("Unable to read %s"),CD.c_str());
+
+   // if we are on a writable medium (like a usb-stick) that is just
+   // used like a cdrom don't use "." as it will constantly change,
+   // use .disk instead
+   if (faccessat(dirfd, ".", W_OK, 0) == 0)
+   {
+      int diskfd = openat(dirfd, "./.disk", O_RDONLY | O_DIRECTORY | O_CLOEXEC, 0);
+      if (diskfd != -1)
+      {
+	 close(dirfd);
+	 dirfd = diskfd;
+	 writable_media = true;
+	 CD = CD.append("/.disk");
+	 if (_config->FindB("Debug::aptcdrom",false) == true)
+	    std::clog << "Found writable cdrom, using alternative path: " << CD
+	       << std::endl;
+      }
+   }
+
+   DIR * const D = fdopendir(dirfd);
+   if (D == nullptr)
+      return _error->Errno("opendir",_("Unable to read %s"),CD.c_str());
+
+   /* Run over the directory, we assume that the reader order will never
+      change as the media is read-only. In theory if the kernel did
+      some sort of wacked caching this might not be true.. */
+   for (struct dirent *Dir = readdir(D); Dir != 0; Dir = readdir(D))
+   {
+      // Skip some files..
+      if (strcmp(Dir->d_name,".") == 0 ||
+	  strcmp(Dir->d_name,"..") == 0)
+	 continue;
+
+      std::string S;
+      if (Version <= 1)
+	 S = std::to_string(Dir->d_ino);
+      else
+      {
+	 struct stat Buf;
+	 if (fstatat(dirfd, Dir->d_name, &Buf, 0) != 0)
+	    continue;
+	 S = std::to_string(Buf.st_mtime);
+      }
+
+      Hash.Add(S.c_str());
+      Hash.Add(Dir->d_name);
+   }
+
+   // Some stats from the fsys
+   std::string S;
+   if (_config->FindB("Debug::identcdrom",false) == false)
+   {
+      struct statvfs Buf;
+      if (fstatvfs(dirfd, &Buf) != 0)
+	 return _error->Errno("statfs",_("Failed to stat the cdrom"));
+
+      // We use a kilobyte block size to avoid overflow
+      S = std::to_string(Buf.f_blocks * (Buf.f_bsize / 1024));
+      if (writable_media == false)
+	 S.append(" ").append(std::to_string(Buf.f_bfree * (Buf.f_bsize / 1024)));
+      Hash.Add(S.c_str(), S.length());
+      strprintf(S, "-%u", Version);
+   }
+   else
+      strprintf(S, "-%u.debug", Version);
+
+   closedir(D);
+   Res = Hash.GetHashString(Hashes::MD5SUM).HashValue().append(std::move(S));
+   return true;
+}
+									/*}}}*/
+// FindMountPointForDevice - Find mountpoint for the given device	/*{{{*/
+string FindMountPointForDevice(const char *devnode)
+{
+   // this is the order that mount uses as well
+   std::vector<std::string> const mounts = _config->FindVector("Dir::state::MountPoints", "/etc/mtab,/proc/mount");
+
+   for (std::vector<std::string>::const_iterator m = mounts.begin(); m != mounts.end(); ++m)
+      if (FileExists(*m) == true)
+      {
+	 char * line = NULL;
+	 size_t line_len = 0;
+	 FILE * f = fopen(m->c_str(), "r");
+	 while(getline(&line, &line_len, f) != -1)
+	 {
+	    char * out[] = { NULL, NULL, NULL };
+	    TokSplitString(' ', line, out, 3);
+	    if (out[2] != NULL || out[1] == NULL || out[0] == NULL)
+	       continue;
+	    if (strcmp(out[0], devnode) != 0)
+	       continue;
+	    fclose(f);
+	    // unescape the \0XXX chars in the path
+	    string mount_point = out[1];
+	    free(line);
+	    return DeEscapeString(mount_point);
+	 }
+	 fclose(f);
+	 free(line);
+      }
+
+   return string();
+}
+									/*}}}*/