From d760567e6974a5b3618aba228f92c188529f6a75 Mon Sep 17 00:00:00 2001 From: Atsushi Torikoshi Date: Wed, 21 Jun 2023 22:20:21 +0900 Subject: [PATCH v11 2/3] Preliminary refactoring for a subsequent patch This is a preparatory patch that doesn't introduce any functional change. Instead, this carries out preliminary refactoring with the goal of reducing the overall nesting level. This helps to prevent the forthcoming patch from further deepening the nesting level. --- src/bin/pg_archivecleanup/pg_archivecleanup.c | 142 +++++++++--------- 1 file changed, 74 insertions(+), 68 deletions(-) diff --git a/src/bin/pg_archivecleanup/pg_archivecleanup.c b/src/bin/pg_archivecleanup/pg_archivecleanup.c index fc0dca9856..982fe00f20 100644 --- a/src/bin/pg_archivecleanup/pg_archivecleanup.c +++ b/src/bin/pg_archivecleanup/pg_archivecleanup.c @@ -93,76 +93,82 @@ CleanupPriorWALFiles(void) struct dirent *xlde; char walfile[MAXPGPATH]; - if ((xldir = opendir(archiveLocation)) != NULL) - { - while (errno = 0, (xlde = readdir(xldir)) != NULL) - { - /* - * Truncation is essentially harmless, because we skip names of - * length other than XLOG_FNAME_LEN. (In principle, one could use - * a 1000-character additional_ext and get trouble.) - */ - strlcpy(walfile, xlde->d_name, MAXPGPATH); - TrimExtension(walfile, additional_ext); - - /* - * We ignore the timeline part of the XLOG segment identifiers in - * deciding whether a segment is still needed. This ensures that - * we won't prematurely remove a segment from a parent timeline. - * We could probably be a little more proactive about removing - * segments of non-parent timelines, but that would be a whole lot - * more complicated. - * - * We use the alphanumeric sorting property of the filenames to - * decide which ones are earlier than the exclusiveCleanupFileName - * file. Note that this means files are not removed in the order - * they were originally written, in case this worries you. - */ - if ((IsXLogFileName(walfile) || IsPartialXLogFileName(walfile)) && - strcmp(walfile + 8, exclusiveCleanupFileName + 8) < 0) - { - char WALFilePath[MAXPGPATH * 2]; /* the file path - * including archive */ - - /* - * Use the original file name again now, including any - * extension that might have been chopped off before testing - * the sequence. - */ - snprintf(WALFilePath, sizeof(WALFilePath), "%s/%s", - archiveLocation, xlde->d_name); - - if (dryrun) - { - /* - * Prints the name of the file to be removed and skips the - * actual removal. The regular printout is so that the - * user can pipe the output into some other program. - */ - printf("%s\n", WALFilePath); - pg_log_debug("file \"%s\" would be removed", WALFilePath); - continue; - } - - pg_log_debug("removing file \"%s\"", WALFilePath); - - rc = unlink(WALFilePath); - if (rc != 0) - pg_fatal("could not remove file \"%s\": %m", - WALFilePath); - } - } - - if (errno) - pg_fatal("could not read archive location \"%s\": %m", - archiveLocation); - if (closedir(xldir)) - pg_fatal("could not close archive location \"%s\": %m", - archiveLocation); - } - else + if ((xldir = opendir(archiveLocation)) == NULL) pg_fatal("could not open archive location \"%s\": %m", archiveLocation); + + while (errno = 0, (xlde = readdir(xldir)) != NULL) + { + char WALFilePath[MAXPGPATH * 2]; /* the file path + * including archive */ + /* + * Truncation is essentially harmless, because we skip names of + * length other than XLOG_FNAME_LEN. (In principle, one could use + * a 1000-character additional_ext and get trouble.) + */ + strlcpy(walfile, xlde->d_name, MAXPGPATH); + TrimExtension(walfile, additional_ext); + + /* + * Check file name. + * + * We skip files which are not WAL file or partial WAL file. + */ + if (!IsXLogFileName(walfile) && !IsPartialXLogFileName(walfile)) + continue; + + /* + * Check cutoff point. + * + * We ignore the timeline part of the XLOG segment identifiers in + * deciding whether a segment is still needed. This ensures that + * we won't prematurely remove a segment from a parent timeline. + * We could probably be a little more proactive about removing + * segments of non-parent timelines, but that would be a whole lot + * more complicated. + * + * We use the alphanumeric sorting property of the filenames to + * decide which ones are earlier than the exclusiveCleanupFileName + * file. Note that this means files are not removed in the order + * they were originally written, in case this worries you. + */ + if (strcmp(walfile + 8, exclusiveCleanupFileName + 8) >= 0) + continue; + + /* + * Use the original file name again now, including any + * extension that might have been chopped off before testing + * the sequence. + */ + snprintf(WALFilePath, sizeof(WALFilePath), "%s/%s", + archiveLocation, xlde->d_name); + + if (dryrun) + { + /* + * Prints the name of the file to be removed and skips the + * actual removal. The regular printout is so that the + * user can pipe the output into some other program. + */ + printf("%s\n", WALFilePath); + pg_log_debug("file \"%s\" would be removed", WALFilePath); + continue; + } + + pg_log_debug("removing file \"%s\"", WALFilePath); + + rc = unlink(WALFilePath); + if (rc != 0) + pg_fatal("could not remove file \"%s\": %m", + WALFilePath); + } + + if (errno) + pg_fatal("could not read archive location \"%s\": %m", + archiveLocation); + if (closedir(xldir)) + pg_fatal("could not close archive location \"%s\": %m", + archiveLocation); } /* -- 2.39.2