Introduce -D, --database

The request of FS#12950 is implemented.

On the backend side, I introduced a new function, alpm_db_set_pkgreason(),
to modify the install reason of a package in the local database. On the
front-end side, I introduced a new main operation, -D/--database, which has
two options, --asdeps and --asexplicit. I documented this in pacman manual.
I've created two pactests to test -D: database001.py and database002.py.

Signed-off-by: Nagy Gabor <ngaba@bibl.u-szeged.hu>
Signed-off-by: Dan McGee <dan@archlinux.org>

2 files changed, 48 insertions, 6 deletions

diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
index 0a2ee846..33291325 100644
--- a/lib/libalpm/alpm.h
+++ b/lib/libalpm/alpm.h
@@ -159,6 +159,15 @@ pmdb_t *alpm_option_get_localdb();
 alpm_list_t *alpm_option_get_syncdbs();
 
 /*
+ * Install reasons -- ie, why the package was installed
+ */
+
+typedef enum _pmpkgreason_t {
+	PM_PKG_REASON_EXPLICIT = 0,  /* explicitly requested by the user */
+	PM_PKG_REASON_DEPEND = 1  /* installed as a dependency for another package */
+} pmpkgreason_t;
+
+/*
  * Databases
  */
 
@@ -181,6 +190,7 @@ alpm_list_t *alpm_db_get_pkgcache(pmdb_t *db);
 pmgrp_t *alpm_db_readgrp(pmdb_t *db, const char *name);
 alpm_list_t *alpm_db_get_grpcache(pmdb_t *db);
 alpm_list_t *alpm_db_search(pmdb_t *db, const alpm_list_t* needles);
+int alpm_db_set_pkgreason(pmdb_t *db, const char *name, pmpkgreason_t reason);
 
 /*
  * Packages
@@ -188,12 +198,6 @@ alpm_list_t *alpm_db_search(pmdb_t *db, const alpm_list_t* needles);
 
 /* Info parameters */
 
-/* reasons -- ie, why the package was installed */
-typedef enum _pmpkgreason_t {
-	PM_PKG_REASON_EXPLICIT = 0,  /* explicitly requested by the user */
-	PM_PKG_REASON_DEPEND = 1  /* installed as a dependency for another package */
-} pmpkgreason_t;
-
 int alpm_pkg_load(const char *filename, int full, pmpkg_t **pkg);
 int alpm_pkg_free(pmpkg_t *pkg);
 int alpm_pkg_checkmd5sum(pmpkg_t *pkg);
diff --git a/lib/libalpm/db.c b/lib/libalpm/db.c
index 6e266501..c8a91a2b 100644
--- a/lib/libalpm/db.c
+++ b/lib/libalpm/db.c
@@ -321,6 +321,44 @@ alpm_list_t SYMEXPORT *alpm_db_search(pmdb_t *db, const alpm_list_t* needles)
 	return(_alpm_db_search(db, needles));
 }
 
+/* Set install reason for a package in db
+ * @param db pointer to the package database
+ * @param name the name of the package
+ * @param reason the new install reason
+ * @return 0 on success, -1 on error (pm_errno is set accordingly)
+ */
+int SYMEXPORT alpm_db_set_pkgreason(pmdb_t *db, const char *name, pmpkgreason_t reason)
+{
+	ALPM_LOG_FUNC;
+
+	/* Sanity checks */
+	ASSERT(handle != NULL, RET_ERR(PM_ERR_HANDLE_NULL, -1));
+	ASSERT(db != NULL && name != NULL, RET_ERR(PM_ERR_WRONG_ARGS, -1));
+
+	pmpkg_t *pkg = _alpm_db_get_pkgfromcache(db, name);
+	if(pkg == NULL) {
+		RET_ERR(PM_ERR_PKG_NOT_FOUND, -1);
+	}
+
+	_alpm_log(PM_LOG_DEBUG, "setting install reason %u for %s/%s\n", reason, db->treename, name);
+	/* read DESC */
+	if(_alpm_db_read(db, pkg, INFRQ_DESC)) {
+		return(-1);
+	}
+	if(pkg->reason == reason) {
+		/* we are done */
+		return(0);
+	}
+	/* set reason (in pkgcache) */
+	pkg->reason = reason;
+	/* write DESC */
+	if(_alpm_db_write(db, pkg, INFRQ_DESC)) {
+		return(-1);
+	}
+
+	return(0);
+}
+
 /** @} */
 
 static pmdb_t *_alpm_db_new(const char *treename, int is_local)