[libxml2] Fix xmllint --maxmem

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 9f4cb84c620bf9a6b7c4880f027e28511349a975
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Sun Jan 16 18:39:51 2022 +0100

    Fix xmllint --maxmem
    
    xmlMemSetup must be called before initializing the parser, otherwise
    some data structures will be allocated with system malloc instead of
    our custom allocator. This throws off built-in memory debugging and
    sanitizers.

 xmllint.c | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)
---
diff --git a/xmllint.c b/xmllint.c
index a3fe10a2..2c7b9d04 100644
--- a/xmllint.c
+++ b/xmllint.c
@@ -3136,7 +3136,28 @@ main(int argc, char **argv) {
        usage(stderr, argv[0]);
        return(1);
     }
+
+    /* xmlMemSetup must be called before initializing the parser. */
+    for (i = 1; i < argc ; i++) {
+       if (!strcmp(argv[i], "-"))
+           break;
+       if (argv[i][0] != '-')
+           continue;
+
+       if ((!strcmp(argv[i], "-maxmem")) ||
+           (!strcmp(argv[i], "--maxmem"))) {
+            i++;
+            if (sscanf(argv[i], "%d", &maxmem) == 1) {
+                xmlMemSetup(myFreeFunc, myMallocFunc, myReallocFunc,
+                            myStrdupFunc);
+            } else {
+                maxmem = 0;
+            }
+        }
+    }
+
     LIBXML_TEST_VERSION
+
     for (i = 1; i < argc ; i++) {
        if (!strcmp(argv[i], "-"))
            break;
@@ -3382,12 +3403,6 @@ main(int argc, char **argv) {
        else if ((!strcmp(argv[i], "-maxmem")) ||
                 (!strcmp(argv[i], "--maxmem"))) {
             i++;
-            if (sscanf(argv[i], "%d", &maxmem) == 1) {
-                xmlMemSetup(myFreeFunc, myMallocFunc, myReallocFunc,
-                            myStrdupFunc);
-            } else {
-                maxmem = 0;
-            }
         }
        else if ((!strcmp(argv[i], "-format")) ||
                 (!strcmp(argv[i], "--format"))) {