conflict.c : fix for FS#8156, detect conflict between symlink and dir.

The previous fileconflict check (package vs filesystem) skipped the conflict
when the file on the filesystem was a directory or a symlink to a directory,
no matter what the file in the package was.
Now, the conflict will only be skipped if the file in the package is a
directory (so compatible with a dir or a dir symlink on the filesystem).

So in the case of 8156 (new fileconflict003 pactest for this case), instead
of silently ignoring the extraction of the test symlink, pacman will now
fail because of a file conflict between the test symlink in the pkg2 package
and the test directory on the filesystem.

Signed-off-by: Chantry Xavier <shiningxc@gmail.com>

2 files changed, 30 insertions, 5 deletions

diff --git a/lib/libalpm/conflict.c b/lib/libalpm/conflict.c
index adad324f..c093705a 100644
--- a/lib/libalpm/conflict.c
+++ b/lib/libalpm/conflict.c
@@ -386,6 +386,7 @@ alpm_list_t *_alpm_db_find_fileconflicts(pmdb_t *db, pmtrans_t *trans, char *roo
 
 		/* loop over each file to be installed */
 		for(j = tmpfiles; j; j = j->next) {
+			int skip_conflict = 0;
 			filestr = j->data;
 
 			snprintf(path, PATH_MAX, "%s%s", root, filestr);
@@ -396,11 +397,17 @@ alpm_list_t *_alpm_db_find_fileconflicts(pmdb_t *db, pmtrans_t *trans, char *roo
 			}
 			stat(path, &sbuf);
 
-			if(S_ISDIR(lsbuf.st_mode)) {
-				_alpm_log(PM_LOG_DEBUG, "%s is a directory, not a conflict\n", path);
-			} 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);
-			} else {
+			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(!skip_conflict) {
 				_alpm_log(PM_LOG_DEBUG, "checking possible conflict: %s\n", path);
 
 				/* Make sure the possible conflict is not a symlink that points to a
diff --git a/pactest/tests/fileconflict003.py b/pactest/tests/fileconflict003.py
new file mode 100644
index 00000000..89696fcb
--- /dev/null
+++ b/pactest/tests/fileconflict003.py
@@ -0,0 +1,18 @@
+self.description = "FS#8156"
+
+p1 = pmpkg("pkg1")
+p1.files = ["test/",
+            "test/file"]
+self.addpkg2db("local", p1)
+
+p2 = pmpkg("pkg2")
+p2.files = ["test2/",
+            "test2/file2",
+            "test -> test2"]
+self.addpkg2db("sync", p2)
+
+self.args = "-S pkg2"
+
+self.addrule("PACMAN_RETCODE=1")
+self.addrule("PKG_EXIST=pkg1")
+self.addrule("!PKG_EXIST=pkg2")