From ef357d06bc054c74ab88fef6edf661ddee151d65 Mon Sep 17 00:00:00 2001
From: Eric Blake <eblake@redhat.com>
Date: Sun, 25 Feb 2018 00:02:37 -0500
Subject: [PATCH] qapi: Simplify use of range.h

Calling our function g_list_insert_sorted_merged is a misnomer,
since we are NOT writing a glib function. Furthermore, we are
making every caller pass the same comparator function of
range_merge(): any caller that would try otherwise would break
in weird ways since our internal call to ranges_can_merge() is
hard-coded to operate only on ranges, rather than paying
attention to the caller's comparator.

Better is to fix things so that callers don't have to care about
our internal comparator, by picking a function name and updating
the parameter type away from a gratuitous use of void*, to make
it obvious that we are operating specifically on a list of ranges
and not a generic list. Plus, refactoring the code here will
make it easier to plug a memory leak in the next patch.

range_compare() is now internal only, and moves to the .c file.

Backports commit 7c47959d0cb05db43014141a156ada0b6d53a750 from qemu
---
 qemu/include/qemu/range.h        | 16 +---------------
 qemu/qapi/string-input-visitor.c | 17 ++++-------------
 qemu/util/range.c                | 20 ++++++++++++++++----
 3 files changed, 21 insertions(+), 32 deletions(-)

diff --git a/qemu/include/qemu/range.h b/qemu/include/qemu/range.h
index b7c2d075..6add664e 100644
--- a/qemu/include/qemu/range.h
+++ b/qemu/include/qemu/range.h
@@ -81,20 +81,6 @@ static inline int ranges_overlap(uint64_t first1, uint64_t len1,
     return !(last2 < first1 || last1 < first2);
 }
 
-GList *g_list_insert_sorted_merged(GList *list, gpointer data,
-                                   GCompareFunc func);
-
-static inline gint range_compare(gconstpointer a, gconstpointer b)
-{
-    Range *ra = (Range *)a, *rb = (Range *)b;
-    if (ra->begin == rb->begin && ra->end == rb->end) {
-        return 0;
-    } else if (range_get_last(ra->begin, ra->end) <
-               range_get_last(rb->begin, rb->end)) {
-        return -1;
-    } else {
-        return 1;
-    }
-}
+GList *range_list_insert(GList *list, Range *data);
 
 #endif
diff --git a/qemu/qapi/string-input-visitor.c b/qemu/qapi/string-input-visitor.c
index a84c86fb..a01140a8 100644
--- a/qemu/qapi/string-input-visitor.c
+++ b/qemu/qapi/string-input-visitor.c
@@ -61,8 +61,7 @@ static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
                 cur = g_malloc0(sizeof(*cur));
                 cur->begin = start;
                 cur->end = start + 1;
-                siv->ranges = g_list_insert_sorted_merged(siv->ranges, cur,
-                                                          range_compare);
+                siv->ranges = range_list_insert(siv->ranges, cur);
                 cur = NULL;
                 str = NULL;
             } else if (*endptr == '-') {
@@ -76,10 +75,7 @@ static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
                         cur = g_malloc0(sizeof(*cur));
                         cur->begin = start;
                         cur->end = end + 1;
-                        siv->ranges =
-                            g_list_insert_sorted_merged(siv->ranges,
-                                                        cur,
-                                                        range_compare);
+                        siv->ranges = range_list_insert(siv->ranges, cur);
                         cur = NULL;
                         str = NULL;
                     } else if (*endptr == ',') {
@@ -87,10 +83,7 @@ static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
                         cur = g_malloc0(sizeof(*cur));
                         cur->begin = start;
                         cur->end = end + 1;
-                        siv->ranges =
-                            g_list_insert_sorted_merged(siv->ranges,
-                                                        cur,
-                                                        range_compare);
+                        siv->ranges = range_list_insert(siv->ranges, cur);
                         cur = NULL;
                     } else {
                         goto error;
@@ -103,9 +96,7 @@ static int parse_str(StringInputVisitor *siv, const char *name, Error **errp)
                 cur = g_malloc0(sizeof(*cur));
                 cur->begin = start;
                 cur->end = start + 1;
-                siv->ranges = g_list_insert_sorted_merged(siv->ranges,
-                                                          cur,
-                                                          range_compare);
+                siv->ranges = range_list_insert(siv->ranges, cur);
                 cur = NULL;
             } else {
                 goto error;
diff --git a/qemu/util/range.c b/qemu/util/range.c
index f775f2e6..dd460926 100644
--- a/qemu/util/range.c
+++ b/qemu/util/range.c
@@ -44,14 +44,26 @@ static void range_merge(Range *range1, Range *range2)
     }
 }
 
-GList *g_list_insert_sorted_merged(GList *list, gpointer data,
-                                   GCompareFunc func)
+static gint range_compare(gconstpointer a, gconstpointer b)
+{
+    Range *ra = (Range *)a, *rb = (Range *)b;
+    if (ra->begin == rb->begin && ra->end == rb->end) {
+        return 0;
+    } else if (range_get_last(ra->begin, ra->end) <
+               range_get_last(rb->begin, rb->end)) {
+        return -1;
+    } else {
+        return 1;
+    }
+}
+
+GList *range_list_insert(GList *list, Range *data)
 {
     GList *l, *next = NULL;
     Range *r, *nextr;
 
     if (!list) {
-        list = g_list_insert_sorted(list, data, func);
+        list = g_list_insert_sorted(list, data, range_compare);
         return list;
     }
 
@@ -74,7 +86,7 @@ GList *g_list_insert_sorted_merged(GList *list, gpointer data,
     }
 
     if (!l) {
-        list = g_list_insert_sorted(list, data, func);
+        list = g_list_insert_sorted(list, data, range_compare);
     }
 
     return list;