From 0d635b615d3fc406b0b3df0637831a799561fa77 Mon Sep 17 00:00:00 2001 From: Robert Haas Date: Mon, 4 Nov 2024 09:55:02 -0500 Subject: [PATCH] pg_combinebackup: When reconstructing, avoid double slash in filename. This function is always called with a relative_path that ends in a slash, so there's no need to insert a second one. So, don't. Instead, add an assertion to verify that nothing gets broken in the future, and adjust the comments. While this is not a critical bug, the duplicate slash is visible in error messages, which could create confusion, so back-patch to v17. This is also better in that it keeps the code consistent across branches. Patch by me, reviewed by Bertrand Drouvot and Amul Sul. Discussion: http://postgr.es/m/CA+TgmoaD7dBYPqe7kMtO0dyto7rd0rUh7joh=JPUSaFszKY6Pg@mail.gmail.com --- src/bin/pg_combinebackup/reconstruct.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/src/bin/pg_combinebackup/reconstruct.c b/src/bin/pg_combinebackup/reconstruct.c index db3f968d271..ae8a5125263 100644 --- a/src/bin/pg_combinebackup/reconstruct.c +++ b/src/bin/pg_combinebackup/reconstruct.c @@ -77,8 +77,9 @@ static void read_block(rfile *s, off_t off, uint8 *buffer); * * relative_path should be the path to the directory containing this file, * relative to the root of the backup (NOT relative to the root of the - * tablespace). bare_file_name should be the name of the file within that - * directory, without "INCREMENTAL.". + * tablespace). It must always end with a trailing slash. bare_file_name + * should be the name of the file within that directory, without + * "INCREMENTAL.". * * n_prior_backups is the number of prior backups, and prior_backup_dirs is * an array of pathnames where those backups can be found. @@ -111,6 +112,10 @@ reconstruct_from_incremental_file(char *input_filename, rfile *copy_source = NULL; pg_checksum_context checksum_ctx; + /* Sanity check the relative_path. */ + Assert(relative_path[0] != '\0'); + Assert(relative_path[strlen(relative_path) - 1] == '/'); + /* * Every block must come either from the latest version of the file or * from one of the prior backups. @@ -174,11 +179,11 @@ reconstruct_from_incremental_file(char *input_filename, * Look for the full file in the previous backup. If not found, then * look for an incremental file instead. */ - snprintf(source_filename, MAXPGPATH, "%s/%s/%s", + snprintf(source_filename, MAXPGPATH, "%s/%s%s", prior_backup_dirs[sidx], relative_path, bare_file_name); if ((s = make_rfile(source_filename, true)) == NULL) { - snprintf(source_filename, MAXPGPATH, "%s/%s/INCREMENTAL.%s", + snprintf(source_filename, MAXPGPATH, "%s/%sINCREMENTAL.%s", prior_backup_dirs[sidx], relative_path, bare_file_name); s = make_incremental_rfile(source_filename); }