path: root/lib/libalpm/remove.c

/*
 *  remove.c
 * 
 *  Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
 *  Copyright (c) 2005 by Aurelien Foret <orelien@chez.com>
 *  Copyright (c) 2005 by Christian Hamar <krics@linuxforum.hu>
 *  Copyright (c) 2006 by David Kimpe <dnaku@frugalware.org>
 *  Copyright (c) 2005, 2006 by Miklos Vajna <vmiklos@frugalware.org>
 * 
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 
 *  USA.
 */

#include "config.h"

#include <stdlib.h>
#include <errno.h>
#include <time.h>
#include <fcntl.h>
#include <string.h>
#include <limits.h>
#include <unistd.h>
#include <sys/stat.h>

/* libalpm */
#include "remove.h"
#include "alpm_list.h"
#include "trans.h"
#include "util.h"
#include "error.h"
#include "log.h"
#include "backup.h"
#include "package.h"
#include "db.h"
#include "cache.h"
#include "deps.h"
#include "provide.h"
#include "handle.h"
#include "alpm.h"

int _alpm_remove_loadtarget(pmtrans_t *trans, pmdb_t *db, char *name)
{
  pmpkg_t *info;

  ALPM_LOG_FUNC;

  ASSERT(db != NULL, RET_ERR(PM_ERR_DB_NULL, -1));
  ASSERT(trans != NULL, RET_ERR(PM_ERR_TRANS_NULL, -1));
  ASSERT(name != NULL, RET_ERR(PM_ERR_WRONG_ARGS, -1));

  if(_alpm_pkg_find(name, trans->packages)) {
    RET_ERR(PM_ERR_TRANS_DUP_TARGET, -1);
  }

  if((info = _alpm_db_scan(db, name)) == NULL) {
    /* Unimportant - just ignore it if we can't find it */
    _alpm_log(PM_LOG_DEBUG, "could not find %s in database\n", name);
    RET_ERR(PM_ERR_PKG_NOT_FOUND, -1);
  }

  /* ignore holdpkgs on upgrade */
  if((trans == handle->trans)
      && alpm_list_find_str(handle->holdpkg, info->name)) {
    int resp = 0;
    QUESTION(trans, PM_TRANS_CONV_REMOVE_HOLDPKG, info, NULL, NULL, &resp);
    if(!resp) {
      RET_ERR(PM_ERR_PKG_HOLD, -1);
    }
  }

  _alpm_log(PM_LOG_DEBUG, "adding %s in the targets list\n", info->name);
  trans->packages = alpm_list_add(trans->packages, info);

  return(0);
}

int _alpm_remove_prepare(pmtrans_t *trans, pmdb_t *db, alpm_list_t **data)
{
  alpm_list_t *lp;

  ALPM_LOG_FUNC;

  ASSERT(db != NULL, RET_ERR(PM_ERR_DB_NULL, -1));
  ASSERT(trans != NULL, RET_ERR(PM_ERR_TRANS_NULL, -1));

  /* skip all checks if we are doing this removal as part of an upgrade */
  if(trans->type == PM_TRANS_TYPE_REMOVEUPGRADE) {
    return(0);
  }

  EVENT(trans, PM_TRANS_EVT_CHECKDEPS_START, NULL, NULL);

  if(!(trans->flags & PM_TRANS_FLAG_NODEPS)) {
    _alpm_log(PM_LOG_DEBUG, "looking for unsatisfied dependencies\n");
    lp = _alpm_checkdeps(db, trans->type, trans->packages);
    if(lp != NULL) {
      if(trans->flags & PM_TRANS_FLAG_CASCADE) {
        while(lp) {
          alpm_list_t *i;
          for(i = lp; i; i = i->next) {
            pmdepmissing_t *miss = (pmdepmissing_t *)i->data;
            pmpkg_t *info = _alpm_db_scan(db, miss->target);
            if(info) {
              if(!_alpm_pkg_find(alpm_pkg_get_name(info), trans->packages)) {
                _alpm_log(PM_LOG_DEBUG, "pulling %s in the targets list\n",
                    alpm_pkg_get_name(info));
                trans->packages = alpm_list_add(trans->packages, info);
              }
            } else {
              _alpm_log(PM_LOG_ERROR, _("could not find %s in database -- skipping\n"),
                        miss->target);
            }
          }
          FREELIST(lp);
          lp = _alpm_checkdeps(db, trans->type, trans->packages);
        }
      } else {
        if(data) {
          *data = lp;
        } else {
          FREELIST(lp);
        }
        RET_ERR(PM_ERR_UNSATISFIED_DEPS, -1);
      }
    }
  }

  if(trans->flags & PM_TRANS_FLAG_RECURSE) {
    _alpm_log(PM_LOG_DEBUG, "finding removable dependencies\n");
    _alpm_recursedeps(db, &trans->packages, 0);
  }

  /* re-order w.r.t. dependencies */ 
  _alpm_log(PM_LOG_DEBUG, "sorting by dependencies\n");
  lp = _alpm_sortbydeps(trans->packages, PM_TRANS_TYPE_REMOVE);
  /* free the old alltargs */
  alpm_list_free(trans->packages);
  trans->packages = lp;

  EVENT(trans, PM_TRANS_EVT_CHECKDEPS_DONE, NULL, NULL);

  return(0);
}

static int can_remove_file(pmtrans_t *trans, const char *path)
{
  char file[PATH_MAX+1];

  snprintf(file, PATH_MAX, "%s%s", handle->root, path);

  if(alpm_list_find_str(trans->skip_remove, file)) {
    /* return success because we will never actually remove this file */
    return(1);
  }
  /* If we fail write permissions due to a read-only filesystem, abort.
   * Assume all other possible failures are covered somewhere else */
  if(access(file, W_OK) == -1) {
    if(errno != EACCES && errno != ETXTBSY && access(file, F_OK) == 0) {
      /* only return failure if the file ACTUALLY exists and we can't write to
       * it - ignore "chmod -w" simple permission failures */
      _alpm_log(PM_LOG_ERROR, _("cannot remove file '%s': %s\n"),
                file, strerror(errno));
      return(0);
    }
  }

  return(1);
}

/* Helper function for iterating through a package's file and deleting them
 * Used by _alpm_remove_commit. */
static void unlink_file(pmpkg_t *info, alpm_list_t *lp, pmtrans_t *trans)
{
  struct stat buf;
  int needbackup = 0;
  char file[PATH_MAX+1];

  ALPM_LOG_FUNC;

  char *hash = _alpm_needbackup(lp->data, alpm_pkg_get_backup(info));
  if(hash) {
    needbackup = 1;
    FREE(hash);
  }
  
  snprintf(file, PATH_MAX, "%s%s", handle->root, (char *)lp->data);

  if(trans->type == PM_TRANS_TYPE_REMOVEUPGRADE) {
    /* check noupgrade */
    if(alpm_list_find_str(handle->noupgrade, lp->data)) {
      _alpm_log(PM_LOG_DEBUG, "Skipping removal of '%s' due to NoUpgrade\n",
          file);
      return;
    }
  }

  if(lstat(file, &buf)) {
    _alpm_log(PM_LOG_DEBUG, "file %s does not exist\n", file);
    return;
  }
  
  if(S_ISDIR(buf.st_mode)) {
    if(rmdir(file)) {
      /* this is okay, other packages are probably using it (like /usr) */
      _alpm_log(PM_LOG_DEBUG, "keeping directory %s\n", file);
    } else {
      _alpm_log(PM_LOG_DEBUG, "removing directory %s\n", file);
    }
  } else {
    /* check the remove skip list before removing the file.
     * see the big comment block in db_find_conflicts() for an
     * explanation. */
    if(alpm_list_find_str(trans->skip_remove, file)) {
      _alpm_log(PM_LOG_DEBUG, "%s is in trans->skip_remove, skipping removal\n",
          file);
      return;
    } else if(needbackup) {
      /* if the file is flagged, back it up to .pacsave */
      if(!(trans->flags & PM_TRANS_FLAG_NOSAVE)) {
        char newpath[PATH_MAX];
        snprintf(newpath, PATH_MAX, "%s.pacsave", file);
        rename(file, newpath);
        _alpm_log(PM_LOG_WARNING, _("%s saved as %s\n"), file, newpath);
        return;
      } else {
        _alpm_log(PM_LOG_DEBUG, "transaction is set to NOSAVE, not backing up '%s'\n", file);
      }
    }
    _alpm_log(PM_LOG_DEBUG, "unlinking %s\n", file);

    if(unlink(file) == -1) {
      _alpm_log(PM_LOG_ERROR, _("cannot remove file '%s': %s\n"),
                (char *)lp->data, strerror(errno));
    }
  }
}

int _alpm_remove_commit(pmtrans_t *trans, pmdb_t *db)
{
  pmpkg_t *info, *infodup;
  alpm_list_t *targ, *lp;
  int pkg_count;

  ALPM_LOG_FUNC;

  ASSERT(db != NULL, RET_ERR(PM_ERR_DB_NULL, -1));
  ASSERT(trans != NULL, RET_ERR(PM_ERR_TRANS_NULL, -1));

  pkg_count = alpm_list_count(trans->packages);

  for(targ = trans->packages; targ; targ = targ->next) {
    int position = 0;
    char scriptlet[PATH_MAX];
    alpm_list_t *files;
    info = (pmpkg_t*)targ->data;
    const char *pkgname = NULL;

    if(handle->trans->state == STATE_INTERRUPTED) {
      return(0);
    }

    /* get the name now so we can use it after package is removed */
    pkgname = alpm_pkg_get_name(info);
    snprintf(scriptlet, PATH_MAX, "%s%s-%s/install", db->path,
             pkgname, alpm_pkg_get_version(info));

    if(trans->type != PM_TRANS_TYPE_REMOVEUPGRADE) {
      EVENT(trans, PM_TRANS_EVT_REMOVE_START, info, NULL);
      _alpm_log(PM_LOG_DEBUG, "removing package %s-%s\n",
                pkgname, alpm_pkg_get_version(info));

      /* run the pre-remove scriptlet if it exists  */
      if(alpm_pkg_has_scriptlet(info) && !(trans->flags & PM_TRANS_FLAG_NOSCRIPTLET)) {
        _alpm_runscriptlet(handle->root, scriptlet, "pre_remove",
                           alpm_pkg_get_version(info), NULL);
      }
    }

    files = alpm_pkg_get_files(info);

    if(!(trans->flags & PM_TRANS_FLAG_DBONLY)) {
      for(lp = files; lp; lp = lp->next) {
        if(!can_remove_file(trans, lp->data)) {
          _alpm_log(PM_LOG_DEBUG, "not removing package '%s', can't remove all files\n",
                    pkgname);
          RET_ERR(PM_ERR_PKG_CANT_REMOVE, -1);
        }
      }

      int filenum = alpm_list_count(files);
      double percent = 0.0;
      _alpm_log(PM_LOG_DEBUG, "removing %d files\n", filenum);

      /* iterate through the list backwards, unlinking files */
      for(lp = alpm_list_last(files); lp; lp = lp->prev) {
        unlink_file(info, lp, trans);

        /* update progress bar after each file */
        percent = (double)position / (double)filenum;
        PROGRESS(trans, PM_TRANS_PROGRESS_REMOVE_START, info->name,
            (double)(percent * 100), pkg_count,
            (pkg_count - alpm_list_count(targ) + 1));
        position++;
      }
    }

    /* set progress to 100% after we finish unlinking files */
    PROGRESS(trans, PM_TRANS_PROGRESS_REMOVE_START, pkgname, 100,
             pkg_count, (pkg_count - alpm_list_count(targ) + 1));

    if(trans->type != PM_TRANS_TYPE_REMOVEUPGRADE) {
      /* run the post-remove script if it exists  */
      if(alpm_pkg_has_scriptlet(info) && !(trans->flags & PM_TRANS_FLAG_NOSCRIPTLET)) {
        _alpm_runscriptlet(handle->root, scriptlet, "post_remove",
                           alpm_pkg_get_version(info), NULL);
      }
    }

    /* duplicate the package so we can remove the requiredby fields later */
    infodup = _alpm_pkg_dup(info);

    /* remove the package from the database */
    _alpm_log(PM_LOG_DEBUG, "updating database\n");
    _alpm_log(PM_LOG_DEBUG, "removing database entry '%s'\n", pkgname);
    if(_alpm_db_remove(db, info) == -1) {
      _alpm_log(PM_LOG_ERROR, _("could not remove database entry %s-%s\n"),
                pkgname, alpm_pkg_get_version(info));
    }
    /* remove the package from the cache */
    if(_alpm_db_remove_pkgfromcache(db, info) == -1) {
      _alpm_log(PM_LOG_ERROR, _("could not remove entry '%s' from cache\n"),
                pkgname);
    }
    
    /* update dependency packages' REQUIREDBY fields */
    _alpm_trans_update_depends(trans, infodup);
    _alpm_pkg_free(infodup);

    /* call a done event if this isn't an upgrade */
    if(trans->type != PM_TRANS_TYPE_REMOVEUPGRADE) {
      EVENT(trans, PM_TRANS_EVT_REMOVE_DONE, info, NULL);
    }
  }

  /* run ldconfig if it exists */
  if(trans->type != PM_TRANS_TYPE_REMOVEUPGRADE) {
    _alpm_log(PM_LOG_DEBUG, "running \"ldconfig -r %s\"\n", handle->root);
    _alpm_ldconfig(handle->root);
  }

  return(0);
}

/* vim: set ts=2 sw=2 noet: */