[pacman-dev] [PATCH] Readd some symlink checking in file conflict code

[Dan McGee]

This patch makes both fileconflict003 and fileconflict004 pactests
successfully pass. It is a rehash of the check was removed in commit
584ffa6aef13d0933ad4930ab9cb70d3af2977ff, but done slightly differently. I'm
still not very fond of this code, and it would be much better if we knew
more about the filelist than a listing of paths- we have no real concept of
whether a to-be-installed file is a symlink, etc.

Issue:
http://archlinux.org/pipermail/pacman-dev/2008-July/012465.html

Signed-off-by: Dan McGee <dan at archlinux.org>
---
 lib/libalpm/conflict.c |   30 ++++++++++++++++++++++--------
 1 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/lib/libalpm/conflict.c b/lib/libalpm/conflict.c
index a8bcdd5..f0e1116 100644
--- a/lib/libalpm/conflict.c
+++ b/lib/libalpm/conflict.c
@@ -434,14 +434,28 @@ alpm_list_t *_alpm_db_find_fileconflicts(pmdb_t *db, pmtrans_t *trans, char *roo
 			}
 			stat(path, &sbuf);
 
-			if(path[strlen(path)-1] == '/') {
-				if(S_ISDIR(lsbuf.st_mode)) {
-					_alpm_log(PM_LOG_DEBUG, "%s is a directory, not a conflict\n", path);
-					skip_conflict = 1;
-				} else if(S_ISLNK(lsbuf.st_mode) && S_ISDIR(sbuf.st_mode)) {
-					_alpm_log(PM_LOG_DEBUG,
-							"%s is a symlink to a dir, hopefully not a conflict\n", path);
-					skip_conflict = 1;
+			if(path[strlen(path)-1] == '/' && S_ISDIR(lsbuf.st_mode)) {
+				_alpm_log(PM_LOG_DEBUG, "%s is a directory, not a conflict\n", path);
+				skip_conflict = 1;
+			} else if(S_ISLNK(lsbuf.st_mode) && S_ISDIR(sbuf.st_mode)) {
+				_alpm_log(PM_LOG_DEBUG,
+						"%s is a symlink to a dir, hopefully not a conflict\n", path);
+				skip_conflict = 1;
+			} else if(S_ISDIR(sbuf.st_mode)) {
+				if(dbpkg) {
+					/* Make sure the possible conflict is not a symlink that points
+					 * to a path in the old package. */
+					struct stat pkgbuf;
+					char str[PATH_MAX+1];
+					for(k = alpm_pkg_get_files(dbpkg); k; k = k->next) {
+						snprintf(str, PATH_MAX, "%s%s", root, (char*)k->data);
+						if(!_alpm_lstat(str, &pkgbuf) && lsbuf.st_ino == pkgbuf.st_ino) {
+							skip_conflict = 1;
+							_alpm_log(PM_LOG_DEBUG,
+									"%s is a symlink to a dir in previous package\n", path);
+							break;
+						}
+					}
 				}
 			}
 			if(!skip_conflict) {
-- 
1.5.6.4