From: Tim Kientzle <kientzle@acm.org>
Date: Wed, 28 May 2025 03:55:15 +0000 (-0700)
Subject: Merge pull request #2642 from stoeckmann/seek_regress
X-Git-Tag: v3.8.1~9
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0dc4f71fcbfde97eac10a2c23188f2dfc74d7a5e;p=thirdparty%2Flibarchive.git

Merge pull request #2642 from stoeckmann/seek_regress

Fix FILE_skip regression

(cherry picked from commit 59b09796c3402489c3f47625b6401a28d24ad8a4)
---

diff --git a/libarchive/archive_read_open_file.c b/libarchive/archive_read_open_file.c
index 6ed18a0c0..742923abb 100644
--- a/libarchive/archive_read_open_file.c
+++ b/libarchive/archive_read_open_file.c
@@ -132,7 +132,7 @@ FILE_skip(struct archive *a, void *client_data, int64_t request)
 #else
 	long skip = (long)request;
 #endif
-	int64_t old_offset, new_offset;
+	int64_t old_offset, new_offset = -1;
 	int skip_bits = sizeof(skip) * 8 - 1;
 
 	(void)a; /* UNUSED */
@@ -170,11 +170,14 @@ FILE_skip(struct archive *a, void *client_data, int64_t request)
 #ifdef __ANDROID__
 			new_offset = lseek(fileno(mine->f), skip, SEEK_CUR);
 #elif HAVE__FSEEKI64
-			new_offset = _fseeki64(mine->f, skip, SEEK_CUR);
+			if (_fseeki64(mine->f, skip, SEEK_CUR) == 0)
+				new_offset = _ftelli64(mine->f);
 #elif HAVE_FSEEKO
-			new_offset = fseeko(mine->f, skip, SEEK_CUR);
+			if (fseeko(mine->f, skip, SEEK_CUR) == 0)
+				new_offset = ftello(mine->f);
 #else
-			new_offset = fseek(mine->f, skip, SEEK_CUR);
+			if (fseek(mine->f, skip, SEEK_CUR) == 0)
+				new_offset = ftell(mine->f);
 #endif
 			if (new_offset >= 0)
 				return (new_offset - old_offset);