Generalized alpm_list_find.

The old alpm_list_find was renamed to alpm_list_find_ptr, and a new
alpm_list_find was introduced, which uses the fn comparison-function
parameter in its decision.
Now both alpm_list_find_ptr (a new ptrcmp helper function was also
added) and alpm_list_find_str are just an alpm_list_find call.

Signed-off-by: Nagy Gabor <ngaba@bibl.u-szeged.hu>
Signed-off-by: Chantry Xavier <shiningxc@gmail.com>
[Dan: made ptrcmp a static function]
Signed-off-by: Dan McGee <dan@archlinux.org>

lib/libalpm/add.c

@@ -282,7 +282,7 @@ static int upgrade_remove(pmpkg_t *oldpkg, pmpkg_t *newpkg, pmtrans_t *trans, pm
 	for(b = alpm_pkg_get_backup(newpkg); b; b = b->next) {
 		const char *backup = b->data;
 		/* make sure we don't add duplicate entries */
-		if(!alpm_list_find(handle->noupgrade, backup)) {
+		if(!alpm_list_find_ptr(handle->noupgrade, backup)) {
 			_alpm_log(PM_LOG_DEBUG, "adding %s to the NoUpgrade array temporarily\n",
 					backup);
 			handle->noupgrade = alpm_list_add(handle->noupgrade, strdup(backup));

lib/libalpm/alpm_list.c

@@ -353,7 +353,7 @@ alpm_list_t SYMEXPORT *alpm_list_remove_dupes(const alpm_list_t *list)
 	const alpm_list_t *lp = list;
 	alpm_list_t *newlist = NULL;
 	while(lp) {
-		if(!alpm_list_find(newlist, lp->data)) {
+		if(!alpm_list_find_ptr(newlist, lp->data)) {
 			newlist = alpm_list_add(newlist, lp->data);
 		}
 		lp = lp->next;
@@ -543,18 +543,18 @@ int SYMEXPORT alpm_list_count(const alpm_list_t *list)
 /**
  * @brief Find an item in a list.
  *
- * Search for the item whos data matches that of the `needle`.
+ * @param needle   the item to search
- *
- * @param needle   the data to search for (== comparison)
  * @param haystack the list
+ * @param fn       the comparison function for searching (!= NULL)
  *
  * @return 1 if `needle` is found, 0 otherwise
  */
-int SYMEXPORT alpm_list_find(const alpm_list_t *haystack, const void *needle)
+int SYMEXPORT alpm_list_find(const alpm_list_t *haystack, const void *needle,
+		alpm_list_fn_cmp fn)
 {
 	const alpm_list_t *lp = haystack;
 	while(lp) {
-		if(lp->data == needle) {
+		if(lp->data && fn(lp->data, needle) == 0) {
 			return(1);
 		}
 		lp = lp->next;
@@ -562,9 +562,29 @@ int SYMEXPORT alpm_list_find(const alpm_list_t *haystack, const void *needle)
 	return(0);
 }
 
+/* trivial helper function for alpm_list_find_ptr */
+static int ptrcmp(const void *p, const void *q)
+{
+	return(p != q);
+}
+
+/**
+ * @brief Find an item in a list.
+ *
+ * Search for the item whos data matches that of the `needle`.
+ *
+ * @param needle   the data to search for (== comparison)
+ * @param haystack the list
+ *
+ * @return 1 if `needle` is found, 0 otherwise
+ */
+int SYMEXPORT alpm_list_find_ptr(const alpm_list_t *haystack, const void *needle)
+{
+	return(alpm_list_find(haystack, needle, ptrcmp));
+}
+
 /**
  * @brief Find a string in a list.
- *        Optimization of alpm_list_find for strings.
  *
  * @param needle   the string to search for
  * @param haystack the list
@@ -573,14 +593,7 @@ int SYMEXPORT alpm_list_find(const alpm_list_t *haystack, const void *needle)
  */
 int SYMEXPORT alpm_list_find_str(const alpm_list_t *haystack, const char *needle)
 {
-	const alpm_list_t *lp = haystack;
+	return(alpm_list_find(haystack, (const void*)needle, (alpm_list_fn_cmp)strcmp));
-	while(lp) {
-		if(lp->data && strcmp((const char *)lp->data, needle) == 0) {
-			return(1);
-		}
-		lp = lp->next;
-	}
-	return(0);
 }
 
 /**

lib/libalpm/alpm_list.h

@@ -72,8 +72,9 @@ void *alpm_list_getdata(const alpm_list_t *entry);
 
 /* misc */
 int alpm_list_count(const alpm_list_t *list);
-int alpm_list_find(const alpm_list_t *haystack, const void *needle);
+int alpm_list_find(const alpm_list_t *haystack, const void *needle, alpm_list_fn_cmp fn);
-int alpm_list_find_str(const alpm_list_t *haystack,const char *needle);
+int alpm_list_find_ptr(const alpm_list_t *haystack, const void *needle);
+int alpm_list_find_str(const alpm_list_t *haystack, const char *needle);
 alpm_list_t *alpm_list_diff(const alpm_list_t *lhs, const alpm_list_t *rhs, alpm_list_fn_cmp fn);
 
 #ifdef __cplusplus

lib/libalpm/db.c

@@ -240,7 +240,7 @@ int SYMEXPORT alpm_db_update(int force, pmdb_t *db)
 	ASSERT(handle->trans->state == STATE_INITIALIZED, RET_ERR(PM_ERR_TRANS_NOT_INITIALIZED, -1));
 	ASSERT(handle->trans->type == PM_TRANS_TYPE_SYNC, RET_ERR(PM_ERR_TRANS_TYPE, -1));
 
-	if(!alpm_list_find(handle->dbs_sync, db)) {
+	if(!alpm_list_find_ptr(handle->dbs_sync, db)) {
 		RET_ERR(PM_ERR_DB_NOT_FOUND, -1);
 	}
 

lib/libalpm/delta.c

@@ -170,7 +170,7 @@ static alpm_list_t *shortest_delta_path(alpm_list_t *deltas,
 
 		/* If this vertex has already been visited in the path, go to the
 		 * next vertex. */
-		if(alpm_list_find(path, v))
+		if(alpm_list_find_ptr(path, v))
 			continue;
 
 		/* Once we find a vertex that starts at the 'from' version,