From 4e2b5b60e003ec67a4854f2625cc610f01428fe2 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Mon, 9 Mar 2020 17:15:00 +0900 Subject: [PATCH v2] Move routine generating restore_command to src/common/ restore_command has only been used until now by the backend, but there is a pending patch for pg_rewind to make use of that in the frontend. Author: Alexey Kondratov Reviewed-by: Andrey Borodin, Andres Freund, Alvaro Herrera, Alexander Korotkov, Michael Paquier Discussion: https://postgr.es/m/a3acff50-5a0d-9a2c-b3b2-ee36168955c1@postgrespro.ru --- src/include/common/archive.h | 29 ++++++ src/backend/access/transam/xlogarchive.c | 62 ++----------- src/common/Makefile | 1 + src/common/archive.c | 110 +++++++++++++++++++++++ src/tools/msvc/Mkvcbuild.pm | 4 +- 5 files changed, 149 insertions(+), 57 deletions(-) create mode 100644 src/include/common/archive.h create mode 100644 src/common/archive.c diff --git a/src/include/common/archive.h b/src/include/common/archive.h new file mode 100644 index 0000000000..805930490b --- /dev/null +++ b/src/include/common/archive.h @@ -0,0 +1,29 @@ +/*------------------------------------------------------------------------- + * + * archive.h + * Common WAL archive routines + * + * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/common/archive.h + * + *------------------------------------------------------------------------- + */ +#ifndef ARCHIVE_H +#define ARCHIVE_H + +/* + * Routine to build a restore command to retrieve WAL segments from a WAL + * archive. This uses the arguments given by the caller to replace the + * corresponding alias fields as defined in the GUC parameter + * restore_command. + */ +extern bool BuildRestoreCommand(const char *restoreCommand, + const char *xlogpath, /* %p */ + const char *xlogfname, /* %f */ + const char *lastRestartPointFname, /* %r */ + char *commandResult, + int commandResultLen); + +#endif /* ARCHIVE_H */ diff --git a/src/backend/access/transam/xlogarchive.c b/src/backend/access/transam/xlogarchive.c index 188b73e752..e1d6df89e1 100644 --- a/src/backend/access/transam/xlogarchive.c +++ b/src/backend/access/transam/xlogarchive.c @@ -21,6 +21,7 @@ #include "access/xlog.h" #include "access/xlog_internal.h" +#include "common/archive.h" #include "miscadmin.h" #include "postmaster/startup.h" #include "replication/walsender.h" @@ -55,9 +56,6 @@ RestoreArchivedFile(char *path, const char *xlogfname, char xlogpath[MAXPGPATH]; char xlogRestoreCmd[MAXPGPATH]; char lastRestartPointFname[MAXPGPATH]; - char *dp; - char *endp; - const char *sp; int rc; struct stat stat_buf; XLogSegNo restartSegNo; @@ -149,58 +147,12 @@ RestoreArchivedFile(char *path, const char *xlogfname, else XLogFileName(lastRestartPointFname, 0, 0L, wal_segment_size); - /* - * construct the command to be executed - */ - dp = xlogRestoreCmd; - endp = xlogRestoreCmd + MAXPGPATH - 1; - *endp = '\0'; - - for (sp = recoveryRestoreCommand; *sp; sp++) - { - if (*sp == '%') - { - switch (sp[1]) - { - case 'p': - /* %p: relative path of target file */ - sp++; - StrNCpy(dp, xlogpath, endp - dp); - make_native_path(dp); - dp += strlen(dp); - break; - case 'f': - /* %f: filename of desired file */ - sp++; - StrNCpy(dp, xlogfname, endp - dp); - dp += strlen(dp); - break; - case 'r': - /* %r: filename of last restartpoint */ - sp++; - StrNCpy(dp, lastRestartPointFname, endp - dp); - dp += strlen(dp); - break; - case '%': - /* convert %% to a single % */ - sp++; - if (dp < endp) - *dp++ = *sp; - break; - default: - /* otherwise treat the % as not special */ - if (dp < endp) - *dp++ = *sp; - break; - } - } - else - { - if (dp < endp) - *dp++ = *sp; - } - } - *dp = '\0'; + /* Build the restore command to execute */ + if (!BuildRestoreCommand(recoveryRestoreCommand, xlogpath, xlogfname, + lastRestartPointFname, xlogRestoreCmd, + MAXPGPATH)) + elog(ERROR, "could not build restore command \"%s\"", + xlogRestoreCmd); ereport(DEBUG3, (errmsg_internal("executing restore command \"%s\"", diff --git a/src/common/Makefile b/src/common/Makefile index ce01df68b9..6939b9d087 100644 --- a/src/common/Makefile +++ b/src/common/Makefile @@ -46,6 +46,7 @@ LIBS += $(PTHREAD_LIBS) # If you add objects here, see also src/tools/msvc/Mkvcbuild.pm OBJS_COMMON = \ + archive.o \ base64.o \ config_info.o \ controldata_utils.o \ diff --git a/src/common/archive.c b/src/common/archive.c new file mode 100644 index 0000000000..74c71e0f4c --- /dev/null +++ b/src/common/archive.c @@ -0,0 +1,110 @@ +/*------------------------------------------------------------------------- + * + * archive.c + * Common WAL archive routines + * + * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/common/archive.c + * + *------------------------------------------------------------------------- + */ + +#ifndef FRONTEND +#include "postgres.h" +#else +#include "postgres_fe.h" +#endif + +#include "common/archive.h" + +/* + * BuildRestoreCommand + * + * Builds a restore command to retrieve a WAL segment from WAL archives, + * replacing the supported aliases with values supplied by the caller: + * xlogpath for %p, xlogfname for %f and lastRestartPointFname for %r. + * Returns true if restore_command was successfully built. + * + * If any of the required arguments is NULL and that the corresponding alias + * is found in the command given by the caller, then false is returned. + * + * The resulting restore command is stored in "commandResult", pre-allocated + * buffer of size "restoreCommandLen". + */ +bool +BuildRestoreCommand(const char *restoreCommand, + const char *xlogpath, + const char *xlogfname, + const char *lastRestartPointFname, + char *commandResult, + int commandResultLen) +{ + char *dp, + *endp; + const char *sp; + + /* + * Build the command to be executed. + */ + dp = commandResult; + endp = commandResult + commandResultLen - 1; + *endp = '\0'; + + for (sp = restoreCommand; *sp; sp++) + { + if (*sp == '%') + { + switch (sp[1]) + { + case 'p': + /* %p: relative path of target file */ + if (xlogpath == NULL) + return false; + sp++; + StrNCpy(dp, xlogpath, endp - dp); + make_native_path(dp); + dp += strlen(dp); + break; + case 'f': + /* %f: filename of desired file */ + if (xlogfname == NULL) + return false; + sp++; + StrNCpy(dp, xlogfname, endp - dp); + dp += strlen(dp); + break; + case 'r': + /* %r: filename of last restartpoint */ + if (lastRestartPointFname == NULL) + return false; + sp++; + StrNCpy(dp, lastRestartPointFname, endp - dp); + dp += strlen(dp); + break; + case '%': + /* convert %% to a single % */ + sp++; + if (dp < endp) + *dp++ = *sp; + break; + default: + /* otherwise treat the % as not special */ + if (dp < endp) + *dp++ = *sp; + break; + } + } + else + { + if (dp < endp) + *dp++ = *sp; + } + } + *dp = '\0'; + + return true; +} diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm index f89a8a4fdb..c648078e20 100644 --- a/src/tools/msvc/Mkvcbuild.pm +++ b/src/tools/msvc/Mkvcbuild.pm @@ -120,8 +120,8 @@ sub mkvcbuild } our @pgcommonallfiles = qw( - base64.c config_info.c controldata_utils.c d2s.c encnames.c exec.c - f2s.c file_perm.c hashfn.c ip.c jsonapi.c + archive.c base64.c config_info.c controldata_utils.c d2s.c encnames.c + exec.c f2s.c file_perm.c hashfn.c ip.c jsonapi.c keywords.c kwlookup.c link-canary.c md5.c pg_lzcompress.c pgfnames.c psprintf.c relpath.c rmtree.c saslprep.c scram-common.c string.c stringinfo.c unicode_norm.c username.c -- 2.25.1