6 * Written by Keith Marshall <keithmarshall@users.sourceforge.net>
7 * Copyright (C) 2011, MinGW Project
10 * Implementation of the primary package removal methods.
13 * This is free software. Permission is granted to copy, modify and
14 * redistribute this software, under the provisions of the GNU General
15 * Public License, Version 3, (or, at your option, any later version),
16 * as published by the Free Software Foundation; see the file COPYING
17 * for licensing details.
19 * Note, in particular, that this software is provided "as is", in the
20 * hope that it may prove useful, but WITHOUT WARRANTY OF ANY KIND; not
21 * even an implied WARRANTY OF MERCHANTABILITY, nor of FITNESS FOR ANY
22 * PARTICULAR PURPOSE. Under no circumstances will the author, or the
23 * MinGW Project, accept liability for any damages, however caused,
24 * arising from the use of this software.
43 #define PKGERR_INVALID_MANIFEST( REASON ) \
44 PKGMSG_INVALID_MANIFEST, tarname, REASON
46 #define PKGMSG_INVALID_MANIFEST "%s: invalid manifest; %s\n"
47 #define PKGMSG_NO_RELEASE_KEY "no release key assigned"
48 #define PKGMSG_RELEASE_KEY_MISMATCH "release key mismatch"
50 static const char *request_key = "request";
52 static __inline__ __attribute__((__always_inline__))
53 pkgXmlNode *sysroot_lookup( pkgXmlNode *pkg, const char *tarname )
55 /* A local helper function, to identify the sysroot association
56 * for any package which is to be uninstalled.
58 pkgSpecs lookup( tarname );
59 return pkg->GetSysRoot( lookup.GetSubSystemName() );
62 static __inline__ __attribute__((__always_inline__))
63 const char *id_lookup( pkgXmlNode *reftag, const char *fallback )
65 /* A local convenience function, to retrieve the value of
66 * the "id" attribute associated with any pkgXmlNode element.
68 return reftag->GetPropVal( id_key, fallback );
71 static __inline__ __attribute__((__always_inline__))
72 const char *pathname_lookup( pkgXmlNode *reftag, const char *fallback )
74 /* A local convenience function, to retrieve the value of
75 * the "id" attribute associated with any pkgXmlNode element.
77 return reftag->GetPropVal( pathname_key, fallback );
80 int pkgActionItem::SetAuthorities( pkgActionItem *current )
82 /* Helper method to either grant or revoke authority for removal of
83 * any package, either permanently when the user requests that it be
84 * removed, or temporarily in preparation for replacement be a newer
85 * version, when scheduled for upgrade.
87 * This is a multiple pass method, iterating over the entire list
88 * of scheduled actions within each pass, until the entire schedule
89 * of authorities has been established.
91 if( (flags & ACTION_PREFLIGHT) == 0 )
93 /* This applies exclusively in the first pass, which is effectively
94 * a "preflight" checking pass only.
96 while( current != NULL )
98 /* Each scheduled action is inspected in turn...
101 if( ((current->flags & ACTION_REMOVE) != 0)
102 && ((ref = current->Selection( to_remove )) != NULL) )
104 /* ...and, when it specifies a "remove" action relating to a
105 * package which has been identified as "installed"...
107 const char *tarname = ref->GetPropVal( tarname_key, value_unknown );
108 DEBUG_INVOKE_IF( DEBUGLEVEL & DEBUG_TRACE_INIT,
109 dmh_printf( "%s: selected for %s\n",
110 (tarname = ref->GetPropVal( tarname_key, value_unknown )),
111 (current->flags & ACTION_INSTALL) ? "upgrade" : "removal"
114 /* ...we identify its associated entry in the installed
115 * package manifest...
117 if( (ref = ref->GetInstallationRecord( tarname )) != NULL )
119 /* ...and then, having confirmed its validity...
121 DEBUG_INVOKE_IF( DEBUGLEVEL & DEBUG_TRACE_INIT,
122 dmh_printf( "%s: marked for %s\n",
123 ref->GetPropVal( tarname_key, value_unknown ),
124 (current->flags & ACTION_INSTALL) ? "upgrade" : "removal"
127 /* ...we mark it as a candidate for removal...
129 ref->SetAttribute( request_key, action_name( ACTION_REMOVE ) );
131 /* ...and assign a provisional grant of authority
132 * to proceed with the removal...
134 current->flags |= ACTION_PREFLIGHT;
137 /* ...then, we move on to perform the same "preflight" check
138 * for the next scheduled action, if any.
140 current = current->next;
142 /* When we get to here, we have completed the "preflight" checks
143 * for all scheduled actions. The "current" pointer has advanced,
144 * but the "this" pointer still refers to the head of the actions
145 * list; terminate this "preflight" pass, marking the associated
146 * entry to confirm that it has been completed.
148 return flags |= ACTION_PREFLIGHT;
151 /* We will get to here only in second and subsequent passes, after
152 * the initial "preflight" checks have been completed. For actions
153 * which schedule a package removal, (whether explicitly, or as an
154 * implicit prerequisite in preparation for upgrade), the initial
155 * pass will have provisionally authorised removal; in subsequent
156 * passes, we either ratify that authority, or we revoke it in the
157 * event that it would break a dependency of another package.
159 * FIXME: we need to develop the code to perform the dependency
160 * analysis; for the time being, we simply return zero, ratifying
161 * authority for all removal requests.
166 pkgXmlNode *pkgManifest::GetSysRootReference( const char *key )
168 /* Method to verify that a package manifest includes
169 * a reference to any sysroot which claims it, returning
170 * a pointer to the first such reference found.
172 if( (this != NULL) && (manifest != NULL) && (key != NULL) )
174 /* We appear to have a valid manifest, and a valid sysroot
175 * key to match; locate this manifest's first, (and nominally
176 * its only), references section.
178 pkgXmlNode *grp = manifest->GetRoot()->FindFirstAssociate( reference_key );
181 /* Having identified a references section, locate the
182 * first sysroot reference contained therein...
184 pkgXmlNode *ref = grp->FindFirstAssociate( sysroot_key );
187 /* ...then retrieve the sysroot ID key value,
188 * for comparison with the requested key...
191 if( ((chk = ref->GetPropVal( id_key, NULL )) != NULL)
192 && (strcmp( chk, key ) == 0) )
194 * ...returning immediately, if a match is found...
198 /* ...otherwise, repeat check for any further sysroot
199 * references which may be present...
201 ref = ref->FindNextAssociate( sysroot_key );
203 /* ...ultimately extending the search into any further
204 * (unlikely) references sections which might be present.
206 grp = grp->FindNextAssociate( reference_key );
209 /* If we fell through the preceding loop, then the expected reference
210 * was not present; return NULL, to report this unexpected result.
215 void pkgManifest::DetachSysRoot( const char *sysroot )
217 /* Method to remove all references to a specified sysroot
218 * from a package manifest; (note that it would be unusual
219 * for a manifest to refer to a given sysroot more than once,
220 * but we repeat the request until we are sure no more such
221 * references exist...
224 while( (ref = GetSysRootReference( sysroot )) != NULL )
226 * ...deleting each one we do find, as we go.
228 ref->GetParent()->DeleteChild( ref );
231 /* Format string used to construct absolute path names from the
232 * "sysroot" relative "pathname" maintained in package manifests;
233 * (shared by "pkg_rmdir()" and "pkg_unlink()" functions).
235 static const char *pkg_path_format = "%s/%s";
237 static __inline__ __attribute__((__always_inline__))
238 int pkg_rmdir( const char *sysroot, const char *pathname )
240 /* Local helper, used to remove directories which become empty
241 * during scheduled package removal; "pathname" is specified from
242 * the package manifest, and is relative to "sysroot", (thus both
243 * must be specified and non-NULL). Return value is non-zero
244 * when the specified directory is successfully removed, or
248 if( (sysroot != NULL) && (pathname != NULL) )
250 /* "sysroot" and "pathname" are both specified. Construct
251 * the absolute path name, and attempt to "rmdir" it, setting
252 * return value as appropriate; silently ignore failure.
254 char fullpath[ mkpath( NULL, sysroot, pathname, NULL ) ];
255 mkpath( fullpath, sysroot, pathname, NULL );
257 DEBUG_INVOKE_IF( DEBUGLEVEL & DEBUG_TRACE_TRANSACTIONS,
258 dmh_printf( " %s: rmdir\n", fullpath )
261 retval = rmdir( fullpath ) == 0;
266 static __inline__ __attribute__((__always_inline__))
267 int pkg_unlink( const char *sysroot, const char *pathname )
269 /* Local helper, used to delete files during scheduled package
270 * removal; "pathname" is specified within the package manifest,
271 * and is relative to "sysroot", (thus both must be specified and
272 * non-NULL). Return value is non-zero when the specified file
273 * is successfully deleted, or zero otherwise.
276 if( (sysroot != NULL) && (pathname != NULL) )
278 char filepath[ mkpath( NULL, sysroot, pathname, NULL ) ];
279 mkpath( filepath, sysroot, pathname, NULL );
281 DEBUG_INVOKE_IF( DEBUGLEVEL & DEBUG_TRACE_TRANSACTIONS,
282 dmh_printf( " %s: unlink file\n", filepath )
285 if( ((retval = unlink( filepath )) != 0) && (errno != ENOENT) )
286 dmh_notify( DMH_WARNING, "%s:unlink failed; %s\n", filepath, strerror( errno ) );
291 EXTERN_C void pkgRemove( pkgActionItem *current )
293 /* Common handler for all package removal tasks...
296 if( (pkg = current->Selection( to_remove )) != NULL )
298 /* We've identified a candidate package for removal;
299 * first, identify the canonical tarname for the package,
300 * and the sysroot with which it is associated.
302 const char *tarname = pkg->GetPropVal( tarname_key, value_unknown );
303 pkgXmlNode *sysroot = sysroot_lookup( pkg, tarname );
305 dmh_printf( " removing %s %s\n", pkg->GetName(), tarname );
307 /* Removal of virtual (meta) packages is comparitively simple;
308 * identified by having an associated archive name of "none", they
309 * have no associated archive file, no installed footprint on disk,
310 * and no associated content manifest to process; thus...
312 if( ! match_if_explicit( pkg->ArchiveName(), value_none ) )
314 /* ...only in the case of packages identified as "real", (which
315 * we expect to be in a substantial majority), do we need to refer
316 * to any installation manifest, to identify actual disk files to
320 pkgManifest inventory( package_key, tarname );
321 pkgXmlNode *ref, *manifest = inventory.GetRoot();
323 /* Perform some sanity checks on the retrieved manifest...
325 if( ((ref = manifest) == NULL)
326 || ((ref = ref->FindFirstAssociate( release_key )) == NULL) )
328 * Mostly "belt-and-braces": this should never happen, because
329 * the manifest constructor should never return a manifest which
330 * lacks a "release" element. If we see this, there is something
331 * seriously wrong; hopefully we will get a bug report.
333 dmh_notify( DMH_ERROR, PKGERR_INVALID_MANIFEST( PKGMSG_NO_RELEASE_KEY ) );
335 else if( ((refname = ref->GetPropVal( tarname_key, NULL )) == NULL)
336 || (strcmp( tarname, refname ) != 0) )
338 /* Another "belt-and-braces" case: once again, it should never
339 * happen, because the manifest constructor should never return
340 * a manifest with a "tarname" attribute in the "release" element
341 * which doesn't match the "tarname" requested.
343 dmh_control( DMH_BEGIN_DIGEST );
344 dmh_notify( DMH_ERROR, PKGERR_INVALID_MANIFEST( PKGMSG_RELEASE_KEY_MISMATCH ) );
345 if( refname != NULL )
346 dmh_notify( DMH_ERROR, "%s: found %s instead\n", tarname, refname );
347 dmh_control( DMH_END_DIGEST );
350 else if( ref->FindNextAssociate( release_key ) != NULL )
352 * Yet another "belt-and-braces" case: the constructor should
353 * never create a manifest which does not have exactly one, and
354 * no more than one, "release" element.
356 dmh_notify( DMH_ERROR, PKGERR_INVALID_MANIFEST( "too many release keys" ) );
358 else if( ((ref = manifest->FindFirstAssociate( reference_key )) == NULL)
359 || (ref->FindFirstAssociate( sysroot_key ) == NULL) )
360 dmh_notify( DMH_ERROR, PKGERR_INVALID_MANIFEST( "no references" ) );
363 { /* We have a manifest which we may likely be able to process;
364 * before proceeding, perform a few sanity checks, and report
365 * any anomalies which may be recoverable.
367 const char *sysname = id_lookup( sysroot, NULL );
368 if( inventory.GetSysRootReference( sysname ) == NULL )
370 /* This indicates that the manifest file itself is lacking
371 * a reference to the sysroot. The sysroot record indicates
372 * that such a reference should be present; diagnose the
373 * anomaly, and proceed anyway.
375 * FIXME: we should probably make this an error condition,
376 * which will suppress processing unless it is overridden by
377 * a user specified option.
379 dmh_notify( DMH_WARNING,
380 "%s: unreferenced in %s\n", sysname, id_lookup( manifest, value_unknown )
383 /* Now, we've validated the manifest, and confirmed that it
384 * correctly records its association with the current sysroot,
385 * (or we've reported the inconsistency; we may proceed with
386 * removal of the associated files.
388 if( (manifest = manifest->FindFirstAssociate( manifest_key )) != NULL )
390 /* The manifest records file pathnames relative to sysroot;
391 * thus, first identify the pathname prefix which identifies
392 * the absolute locations of the files and directories which
393 * are to be purged; (note that we specify this as a template
394 * for use with mkpath(), rather than as a simple path name,
395 * so that macros--esp. "%R"--may be correctly resolved at
398 const char *refpath = pathname_lookup( sysroot, value_unknown );
399 char syspath[4 + strlen( refpath )]; sprintf( syspath, "%s%%/F", refpath );
401 /* Read the package manifest...
406 /* ...selecting records identifying installed files...
408 pkgXmlNode *files = ref->FindFirstAssociate( filename_key );
409 while( files != NULL )
411 /* ...and delete each in turn...
413 pkg_unlink( syspath, pathname_lookup( files, NULL ) );
415 * ...before moving on to the next in the list.
417 files = files->FindNextAssociate( filename_key );
419 /* It should not be, but allow for the possibility that
420 * the manifest is subdivided into multiple sections.
422 ref = ref->FindNextAssociate( manifest_key );
425 /* Having deleted all files associated with the package,
426 * we attempt to prune any directories, which may have been
427 * created during the installation of this package, from the
428 * file system tree. We note that we may remove only those
429 * directories which no longer contain any files or other
430 * subdirectories, (i.e. those which are leaf directories
431 * within the file system). We also note that many of the
432 * directories associated with the package being removed
433 * may also contain files belonging to other packages; thus
434 * we do not consider it to be an error if we are unable to
435 * remove any directory specified in the package manifest.
437 * Removal of any leaf directory may expose its own parent
438 * as a new leaf, which may then itself become a candidate
439 * for removal; thus we adopt an iterative removal procedure,
440 * restarting with a further iteration after any pass through
441 * the manifest in which any directory is removed.
445 /* Process the entire manifest on each iteration;
446 * initially assume that no restart will be required.
448 ref = manifest; restart = false;
451 /* Select manifest records which specify directories...
453 pkgXmlNode *dir = ref->FindFirstAssociate( dirname_key );
456 /* ...attempting to remove each in turn; request a
457 * restart when at least one such attempt succeeds...
459 restart |= pkg_rmdir( syspath, pathname_lookup( dir, NULL ) );
461 * ...then move on to the next record, if any.
463 dir = dir->FindNextAssociate( dirname_key );
465 /* As in the case of file removal, allow for the
466 * possibility of a multisectional manifest.
468 ref = ref->FindNextAssociate( manifest_key );
470 /* Restart the directory removal process, with a new
471 * iteration through the entire manifest, until no more
472 * listed directories can be removed.
476 /* Finally, disassociate the package manifest from the active sysroot;
477 * this will automatically delete the manifest itself, unless it has a
478 * further association with any other sysroot, (e.g. in an alternative
481 inventory.DetachSysRoot( sysname );
485 /* In the case of both real and virtual packages, the final phase of removal
486 * is to expunge the installation record from the associated sysroot element
487 * within the system map; (that is, any record of type "installed" contained
488 * within the sysroot element referenced by the "sysroot" pointer identified
489 * above, with a tarname attribute which matches "tarname").
491 pkgXmlNode *expunge, *instrec = sysroot->FindFirstAssociate( installed_key );
492 while( (expunge = instrec) != NULL )
494 /* Consider each installation record in turn, as a possible candidate for
495 * deletion; in any case, always locate the NEXT candidate, BEFORE deleting
496 * a matched record, so we don't destroy our point of reference, whence we
497 * must continue the search.
499 instrec = instrec->FindNextAssociate( installed_key );
500 if( strcmp( tarname, expunge->GetPropVal( tarname_key, value_unknown )) == 0 )
502 /* The CURRENT candidate matches the "tarname" criterion for deletion;
503 * we may delete it, also marking the sysroot record as "modified", so
504 * that the change will be committed to disk.
506 sysroot->DeleteChild( expunge );
507 sysroot->SetAttribute( modified_key, value_yes );
513 /* $RCSfile$: end of file */