libopkg: implement lightweight package listing logic
[oweals/opkg-lede.git] / libopkg / opkg_remove.c
1 /* opkg_remove.c - the opkg package management system
2
3    Carl D. Worth
4
5    Copyright (C) 2001 University of Southern California
6
7    This program is free software; you can redistribute it and/or
8    modify it under the terms of the GNU General Public License as
9    published by the Free Software Foundation; either version 2, or (at
10    your option) any later version.
11
12    This program is distributed in the hope that it will be useful, but
13    WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15    General Public License for more details.
16 */
17
18 #include <stdio.h>
19 #include <glob.h>
20 #include <unistd.h>
21
22 #include "opkg_message.h"
23 #include "opkg_remove.h"
24 #include "opkg_cmd.h"
25 #include "pkg_alternatives.h"
26 #include "file_util.h"
27 #include "sprintf_alloc.h"
28 #include "libbb/libbb.h"
29
30 /*
31  * Returns number of the number of packages depending on the packages provided by this package.
32  * Every package implicitly provides itself.
33  */
34 int pkg_has_installed_dependents(pkg_t * pkg, abstract_pkg_t *** pdependents)
35 {
36         abstract_pkg_t **provider, **provides = pkg_get_ptr(pkg, PKG_PROVIDES);
37         unsigned int i, n_installed_dependents = 0;
38
39         provider = provides;
40
41         while (provider && *provider) {
42                 abstract_pkg_t *providee = *provider++;
43                 abstract_pkg_t **dependers = providee->depended_upon_by;
44                 abstract_pkg_t *dep_ab_pkg;
45                 if (dependers == NULL)
46                         continue;
47                 while ((dep_ab_pkg = *dependers++) != NULL) {
48                         if (dep_ab_pkg->state_status == SS_INSTALLED) {
49                                 n_installed_dependents++;
50                         }
51                 }
52         }
53
54         /* if caller requested the set of installed dependents */
55         if (pdependents) {
56                 int p = 0;
57                 abstract_pkg_t **dependents =
58                     xcalloc((n_installed_dependents + 1),
59                             sizeof(abstract_pkg_t *));
60
61                 provider = provides;
62                 *pdependents = dependents;
63
64                 while (provider && *provider) {
65                         abstract_pkg_t *providee = *provider++;
66                         abstract_pkg_t **dependers = providee->depended_upon_by;
67                         abstract_pkg_t *dep_ab_pkg;
68                         if (dependers == NULL)
69                                 continue;
70                         while ((dep_ab_pkg = *dependers++) != NULL) {
71                                 if (dep_ab_pkg->state_status == SS_INSTALLED
72                                     && !(dep_ab_pkg->state_flag & SF_MARKED)) {
73                                         dependents[p++] = dep_ab_pkg;
74                                         dep_ab_pkg->state_flag |= SF_MARKED;
75                                 }
76                         }
77                 }
78                 dependents[p] = NULL;
79                 /* now clear the marks */
80                 for (i = 0; i < p; i++) {
81                         abstract_pkg_t *dep_ab_pkg = dependents[i];
82                         dep_ab_pkg->state_flag &= ~SF_MARKED;
83                 }
84         }
85         return n_installed_dependents;
86 }
87
88 static int opkg_remove_dependent_pkgs(pkg_t * pkg, abstract_pkg_t ** dependents)
89 {
90         int i;
91         int a;
92         int count;
93         pkg_vec_t *dependent_pkgs;
94         abstract_pkg_t *ab_pkg;
95
96         if ((ab_pkg = pkg->parent) == NULL) {
97                 opkg_msg(ERROR, "Internal error: pkg %s isn't in hash table\n",
98                          pkg->name);
99                 return 0;
100         }
101
102         if (dependents == NULL)
103                 return 0;
104
105         // here i am using the dependencies_checked
106         if (ab_pkg->dependencies_checked == 2)  // variable to make out whether this package
107                 return 0;       // has already been encountered in the process
108         // of marking packages for removal - Karthik
109         ab_pkg->dependencies_checked = 2;
110
111         i = 0;
112         count = 1;
113         dependent_pkgs = pkg_vec_alloc();
114
115         while (dependents[i] != NULL) {
116                 abstract_pkg_t *dep_ab_pkg = dependents[i];
117
118                 if (dep_ab_pkg->dependencies_checked == 2) {
119                         i++;
120                         continue;
121                 }
122                 if (dep_ab_pkg->state_status == SS_INSTALLED) {
123                         for (a = 0; a < dep_ab_pkg->pkgs->len; a++) {
124                                 pkg_t *dep_pkg = dep_ab_pkg->pkgs->pkgs[a];
125                                 if (dep_pkg->state_status == SS_INSTALLED) {
126                                         pkg_vec_insert(dependent_pkgs, dep_pkg);
127                                         count++;
128                                 }
129                         }
130                 }
131                 i++;
132                 /* 1 - to keep track of visited ab_pkgs when checking for possiblility of a broken removal of pkgs.
133                  * 2 - to keep track of pkgs whose deps have been checked alrdy  - Karthik */
134         }
135
136         if (count == 1) {
137                 pkg_vec_free(dependent_pkgs);
138                 return 0;
139         }
140
141         int err = 0;
142         for (i = 0; i < dependent_pkgs->len; i++) {
143                 err = opkg_remove_pkg(dependent_pkgs->pkgs[i], 0);
144                 if (err) {
145                         break;
146                 }
147         }
148         pkg_vec_free(dependent_pkgs);
149         return err;
150 }
151
152 static void print_dependents_warning(pkg_t * pkg, abstract_pkg_t ** dependents)
153 {
154         abstract_pkg_t *dep_ab_pkg;
155         opkg_msg(ERROR, "Package %s is depended upon by packages:\n",
156                  pkg->name);
157         while ((dep_ab_pkg = *dependents++) != NULL) {
158                 if (dep_ab_pkg->state_status == SS_INSTALLED)
159                         opkg_msg(ERROR, "\t%s\n", dep_ab_pkg->name);
160         }
161         opkg_msg(ERROR,
162                  "These might cease to work if package %s is removed.\n\n",
163                  pkg->name);
164         opkg_msg(ERROR,
165                  "Force removal of this package with --force-depends.\n");
166         opkg_msg(ERROR, "Force removal of this package and its dependents\n");
167         opkg_msg(ERROR, "with --force-removal-of-dependent-packages.\n");
168 }
169
170 /*
171  * Find and remove packages that were autoinstalled and are orphaned
172  * by the removal of pkg.
173  */
174 static int remove_autoinstalled(pkg_t * pkg)
175 {
176         int j;
177         int err = 0;
178         int n_deps;
179         pkg_t *p;
180         struct compound_depend *cdep;
181         abstract_pkg_t **dependents;
182
183         for (cdep = pkg_get_ptr(pkg, PKG_DEPENDS); cdep && cdep->type; cdep++) {
184                 if (cdep->type != PREDEPEND
185                     && cdep->type != DEPEND && cdep->type != RECOMMEND)
186                         continue;
187                 for (j = 0; j < cdep->possibility_count; j++) {
188                         p = pkg_hash_fetch_installed_by_name(cdep->
189                                                              possibilities[j]->
190                                                              pkg->name);
191
192                         /* If the package is not installed, this could have
193                          * been a circular dependency and the package has
194                          * already been removed.
195                          */
196                         if (!p)
197                                 return -1;
198
199                         if (!p->auto_installed)
200                                 continue;
201
202                         n_deps = pkg_has_installed_dependents(p, &dependents);
203                         if (n_deps == 0) {
204                                 opkg_msg(NOTICE, "%s was autoinstalled and is "
205                                          "now orphaned, removing.\n", p->name);
206                                 if (opkg_remove_pkg(p, 0) != 0) {
207                                         err = -1;
208                                 }
209                         } else
210                                 opkg_msg(INFO, "%s was autoinstalled and is "
211                                          "still required by %d "
212                                          "installed packages.\n",
213                                          p->name, n_deps);
214
215                         if (dependents)
216                                 free(dependents);
217                 }
218         }
219
220         return err;
221 }
222
223 int opkg_remove_pkg(pkg_t * pkg, int from_upgrade)
224 {
225         int err;
226         abstract_pkg_t *parent_pkg = NULL;
227
228 /*
229  * If called from an upgrade and not from a normal remove,
230  * ignore the essential flag.
231  */
232         if (pkg->essential && !from_upgrade) {
233                 if (conf->force_removal_of_essential_packages) {
234                         opkg_msg(NOTICE,
235                                  "Removing essential package %s under your coercion.\n"
236                                  "\tIf your system breaks, you get to keep both pieces\n",
237                                  pkg->name);
238                 } else {
239                         opkg_msg(NOTICE,
240                                  "Refusing to remove essential package %s.\n"
241                                  "\tRemoving an essential package may lead to an unusable system, but if\n"
242                                  "\tyou enjoy that kind of pain, you can force opkg to proceed against\n"
243                                  "\tits will with the option: --force-removal-of-essential-packages\n",
244                                  pkg->name);
245                         return -1;
246                 }
247         }
248
249         if ((parent_pkg = pkg->parent) == NULL)
250                 return 0;
251
252         /* only attempt to remove dependent installed packages if
253          * force_depends is not specified or the package is being
254          * replaced.
255          */
256         if (!conf->force_depends && !(pkg->state_flag & SF_REPLACE)) {
257                 abstract_pkg_t **dependents;
258                 int has_installed_dependents =
259                     pkg_has_installed_dependents(pkg, &dependents);
260
261                 if (has_installed_dependents) {
262                         /*
263                          * if this package is depended upon by others, then either we should
264                          * not remove it or we should remove it and all of its dependents
265                          */
266
267                         if (!conf->force_removal_of_dependent_packages) {
268                                 print_dependents_warning(pkg, dependents);
269                                 free(dependents);
270                                 return -1;
271                         }
272
273                         /* remove packages depending on this package - Karthik */
274                         err = opkg_remove_dependent_pkgs(pkg, dependents);
275                         if (err) {
276                                 free(dependents);
277                                 return err;
278                         }
279                 }
280                 if (dependents)
281                         free(dependents);
282         }
283
284         if (from_upgrade == 0) {
285                 opkg_msg(NOTICE, "Removing package %s from %s...\n",
286                          pkg->name, pkg->dest->name);
287         }
288         pkg->state_flag |= SF_FILELIST_CHANGED;
289
290         pkg->state_want = SW_DEINSTALL;
291         opkg_state_changed++;
292
293         if (pkg_run_script(pkg, "prerm", "remove") != 0) {
294                 if (!conf->force_remove) {
295                         opkg_msg(ERROR, "not removing package \"%s\", "
296                                  "prerm script failed\n", pkg->name);
297                         opkg_msg(NOTICE,
298                                  "You can force removal of packages with failed "
299                                  "prerm scripts with the option: \n"
300                                  "\t--force-remove\n");
301                         return -1;
302                 }
303         }
304
305         /* DPKG_INCOMPATIBILITY: dpkg is slightly different here. It
306            maintains an empty filelist rather than deleting it. That seems
307            like a big pain, and I don't see that that should make a big
308            difference, but for anyone who wants tighter compatibility,
309            feel free to fix this. */
310         remove_data_files_and_list(pkg);
311
312         err = pkg_run_script(pkg, "postrm", "remove");
313
314         remove_maintainer_scripts(pkg);
315         pkg->state_status = SS_NOT_INSTALLED;
316         pkg_alternatives_update(pkg);
317
318         if (parent_pkg)
319                 parent_pkg->state_status = SS_NOT_INSTALLED;
320
321         /* remove autoinstalled packages that are orphaned by the removal of this one */
322         if (conf->autoremove) {
323                 if (remove_autoinstalled(pkg) != 0) {
324                         err = -1;
325                 }
326         }
327         return err;
328 }
329
330 void remove_data_files_and_list(pkg_t * pkg)
331 {
332         str_list_t installed_dirs;
333         str_list_t *installed_files;
334         str_list_elt_t *iter;
335         char *file_name;
336         conffile_t *conffile;
337         int removed_a_dir;
338         pkg_t *owner;
339         int rootdirlen = 0;
340
341         installed_files = pkg_get_installed_files(pkg);
342         if (installed_files == NULL) {
343                 opkg_msg(ERROR, "Failed to determine installed "
344                          "files for %s. None removed.\n", pkg->name);
345                 return;
346         }
347
348         str_list_init(&installed_dirs);
349
350         /* don't include trailing slash */
351         if (conf->offline_root)
352                 rootdirlen = strlen(conf->offline_root);
353
354         for (iter = str_list_first(installed_files); iter;
355              iter = str_list_next(installed_files, iter)) {
356                 file_name = (char *)iter->data;
357
358                 owner = file_hash_get_file_owner(file_name);
359                 if (owner != pkg)
360                         /* File may have been claimed by another package. */
361                         continue;
362
363                 if (file_is_dir(file_name)) {
364                         str_list_append(&installed_dirs, file_name);
365                         continue;
366                 }
367
368                 conffile = pkg_get_conffile(pkg, file_name + rootdirlen);
369                 if (conffile) {
370                         if (conffile_has_been_modified(conffile)) {
371                                 opkg_msg(NOTICE,
372                                          "Not deleting modified conffile %s.\n",
373                                          file_name);
374                                 continue;
375                         }
376                 }
377
378                 if (!conf->noaction) {
379                         opkg_msg(INFO, "Deleting %s.\n", file_name);
380                         unlink(file_name);
381                 } else
382                         opkg_msg(INFO, "Not deleting %s. (noaction)\n",
383                                  file_name);
384
385                 file_hash_remove(file_name);
386         }
387
388         /* Remove empty directories */
389         if (!conf->noaction) {
390                 do {
391                         removed_a_dir = 0;
392                         for (iter = str_list_first(&installed_dirs); iter;
393                              iter = str_list_next(&installed_dirs, iter)) {
394                                 file_name = (char *)iter->data;
395
396                                 if (rmdir(file_name) == 0) {
397                                         opkg_msg(INFO, "Deleting %s.\n",
398                                                  file_name);
399                                         removed_a_dir = 1;
400                                         str_list_remove(&installed_dirs, &iter);
401                                 }
402                         }
403                 } while (removed_a_dir);
404         }
405
406         pkg_free_installed_files(pkg);
407         pkg_remove_installed_files_list(pkg);
408
409         /* Don't print warning for dirs that are provided by other packages */
410         for (iter = str_list_first(&installed_dirs); iter;
411              iter = str_list_next(&installed_dirs, iter)) {
412                 file_name = (char *)iter->data;
413
414                 owner = file_hash_get_file_owner(file_name);
415                 if (owner) {
416                         free(iter->data);
417                         iter->data = NULL;
418                         str_list_remove(&installed_dirs, &iter);
419                 }
420         }
421
422         /* cleanup */
423         while (!void_list_empty(&installed_dirs)) {
424                 iter = str_list_pop(&installed_dirs);
425                 free(iter->data);
426                 free(iter);
427         }
428         str_list_deinit(&installed_dirs);
429 }
430
431 void remove_maintainer_scripts(pkg_t * pkg)
432 {
433         int i, err;
434         char *globpattern;
435         glob_t globbuf;
436
437         if (conf->noaction)
438                 return;
439
440         sprintf_alloc(&globpattern, "%s/%s.*", pkg->dest->info_dir, pkg->name);
441
442         err = glob(globpattern, 0, NULL, &globbuf);
443         free(globpattern);
444         if (err)
445                 return;
446
447         for (i = 0; i < globbuf.gl_pathc; i++) {
448                 opkg_msg(INFO, "Deleting %s.\n", globbuf.gl_pathv[i]);
449                 unlink(globbuf.gl_pathv[i]);
450         }
451         globfree(&globbuf);
452 }