From 186e0ab025b9ad92d900697f611633a6f6162f3b Mon Sep 17 00:00:00 2001
From: Panu Matilainen <pmatilai@redhat.com>
Date: Wed, 9 Feb 2022 14:47:14 +0200
Subject: [PATCH] Add optional callback on directory changes during rpmfi
 iteration

Internal only for now in case we need to fiddle with the API some more,
but no reason this couldn't be made public later.
---
 lib/rpmfi.c          | 24 ++++++++++++++++++++----
 lib/rpmfi_internal.h | 17 +++++++++++++++++
 2 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/lib/rpmfi.c b/lib/rpmfi.c
index aec8220a3..6c631fdb5 100644
--- a/lib/rpmfi.c
+++ b/lib/rpmfi.c
@@ -53,6 +53,9 @@ struct rpmfi_s {
     int intervalStart;		/*!< Start of iterating interval. */
     int intervalEnd;		/*!< End of iterating interval. */
 
+    rpmfiChdirCb onChdir;	/*!< Callback for directory changes */
+    void *onChdirData;		/*!< Caller private callback data */
+
     rpmfiles files;		/*!< File info set */
     rpmcpio_t archive;		/*!< Archive with payload */
     unsigned char * found;	/*!< Bit field of files found in the archive */
@@ -298,11 +301,16 @@ rpm_count_t rpmfiDC(rpmfi fi)
     return (fi != NULL ? rpmfilesDC(fi->files) : 0);
 }
 
-#ifdef	NOTYET
-int rpmfiDI(rpmfi fi)
+int rpmfiSetOnChdir(rpmfi fi, rpmfiChdirCb cb, void *data)
 {
+    int rc = -1;
+    if (fi != NULL) {
+	fi->onChdir = cb;
+	fi->onChdirData = data;
+	rc = 0;
+    }
+    return rc;
 }
-#endif
 
 int rpmfiFX(rpmfi fi)
 {
@@ -314,9 +322,17 @@ int rpmfiSetFX(rpmfi fi, int fx)
     int i = -1;
 
     if (fi != NULL && fx >= 0 && fx < rpmfilesFC(fi->files)) {
+	int dx = fi->j;
 	i = fi->i;
 	fi->i = fx;
 	fi->j = rpmfilesDI(fi->files, fi->i);
+	i = fi->i;
+
+	if (fi->j != dx && fi->onChdir) {
+	    int chrc = fi->onChdir(fi, fi->onChdirData);
+	    if (chrc < 0)
+		i = chrc;
+	}
     }
     return i;
 }
@@ -1682,9 +1698,9 @@ static rpmfi initIter(rpmfiles files, int itype, int link)
     if (files && itype>=0 && itype<=RPMFILEITERMAX) {
 	fi = xcalloc(1, sizeof(*fi)); 
 	fi->i = -1;
+	fi->j = -1;
 	fi->files = link ? rpmfilesLink(files) : files;
 	fi->next = nextfuncs[itype];
-	fi->i = -1;
 	if (itype == RPMFI_ITER_BACK) {
 	    fi->i = rpmfilesFC(fi->files);
 	} else if (itype >=RPMFI_ITER_READ_ARCHIVE
diff --git a/lib/rpmfi_internal.h b/lib/rpmfi_internal.h
index dccc6ccbe..37f1d45f5 100644
--- a/lib/rpmfi_internal.h
+++ b/lib/rpmfi_internal.h
@@ -13,6 +13,23 @@
 extern "C" {
 #endif
 
+/** \ingroup rpmfi
+ * Callback on file iterator directory changes
+ * @param fi		file info
+ * @param data		caller private callback data
+ * @return		0 on success, < 0 on error (to stop iteration)
+ */
+typedef int (*rpmfiChdirCb)(rpmfi fi, void *data);
+
+/** \ingroup rpmfi
+ * Set a callback for directory changes during iteration.
+ * @param fi		file info
+ * @param cb		callback function
+ * @param data		caller private callback data
+ * @return		string pool handle (weak reference)
+ */
+int rpmfiSetOnChdir(rpmfi fi, rpmfiChdirCb cb, void *data);
+
 /** \ingroup rpmfi
  * Return file info set string pool handle
  * @param fi		file info
-- 
2.41.0