/*
* resolve_symlinks - resolve symlinks to the underlying file
*
* Replace "path" by the absolute path to the referenced file.
*
* Returns 0 if OK, -1 if error.
*
* Note: we are not particularly tense about producing nice error messages
* because we are not really expecting error here; we just determined that
* the symlink does point to a valid executable.
*/
static int
resolve_symlinks(char *path)
{
#ifdef HAVE_READLINK
struct stat buf;
char orig_wd[MAXPGPATH],
link_buf[MAXPGPATH];
char *fname;
/*
* To resolve a symlink properly, we have to chdir into its directory and
* then chdir to where the symlink points; otherwise we may fail to
* resolve relative links correctly (consider cases involving mount
* points, for example). After following the final symlink, we use
* getcwd() to figure out where the heck we're at.
*
* One might think we could skip all this if path doesn't point to a
* symlink to start with, but that's wrong. We also want to get rid of
* any directory symlinks that are present in the given path. We expect
* getcwd() to give us an accurate, symlink-free path.
*/
if (!getcwd(orig_wd, MAXPGPATH))
{
log_error(_("could not identify current directory: %s"),
strerror(errno));
return -1;
}
for (;;)
{
char *lsep;
int rllen;
lsep = last_dir_separator(path);
if (lsep)
{
*lsep = '\0';
if (chdir(path) == -1)
{
log_error(_("could not change directory to \"%s\""), path);
return -1;
}
fname = lsep + 1;
}
else
fname = path;
if (lstat(fname, &buf) < 0 ||
!S_ISLNK(buf.st_mode))
break;
rllen = readlink(fname, link_buf, sizeof(link_buf));
if (rllen < 0 || rllen >= sizeof(link_buf))
{
log_error(_("could not read symbolic link \"%s\""), fname);
return -1;
}
link_buf[rllen] = '\0';
strcpy(path, link_buf);
}
/* must copy final component out of 'path' temporarily */
strcpy(link_buf, fname);
if (!getcwd(path, MAXPGPATH))
{
log_error(_("could not identify current directory: %s"),
strerror(errno));
return -1;
}
join_path_components(path, path, link_buf);
canonicalize_path(path);
if (chdir(orig_wd) == -1)
{
log_error(_("could not change directory to \"%s\""), orig_wd);
return -1;
}
#endif /* HAVE_READLINK */
return 0;
}
/*
* find_my_exec -- find an absolute path to a valid executable
*
* argv0 is the name passed on the command line
* retpath is the output area (must be of size MAXPGPATH)
* Returns 0 if OK, -1 if error.
*
* The reason we have to work so hard to find an absolute path is that
* on some platforms we can't do dynamic loading unless we know the
* executable's location. Also, we need a full path not a relative
* path because we will later change working directory. Finally, we want
* a true path not a symlink location, so that we can locate other files
* that are part of our installation relative to the executable.
*
* This function is not thread-safe because it calls validate_exec(),
* which calls getgrgid(). This function should be used only in
* non-threaded binaries, not in library routines.
*/
int
find_my_exec(const char *argv0, char *retpath)
{
char cwd[MAXPGPATH],
test_path[MAXPGPATH];
char *path;
if (!getcwd(cwd, MAXPGPATH))
{
log_error(_("could not identify current directory: %s"),
strerror(errno));
return -1;
}
/*
* If argv0 contains a separator, then PATH wasn't used.
*/
if (first_dir_separator(argv0) != NULL)
{
if (is_absolute_path(argv0))
StrNCpy(retpath, argv0, MAXPGPATH);
else
join_path_components(retpath, cwd, argv0);
canonicalize_path(retpath);
if (validate_exec(retpath) == 0)
return resolve_symlinks(retpath);
log_error(_("invalid binary \"%s\""), retpath);
return -1;
}
#ifdef WIN32
/* Win32 checks the current directory first for names without slashes */
join_path_components(retpath, cwd, argv0);
if (validate_exec(retpath) == 0)
return resolve_symlinks(retpath);
#endif
/*
* Since no explicit path was supplied, the user must have been relying on
* PATH. We'll search the same PATH.
*/
if ((path = getenv("PATH")) && *path)
{
char *startp = NULL,
*endp = NULL;
do
{
if (!startp)
startp = path;
else
startp = endp + 1;
endp = first_path_separator(startp);
if (!endp)
endp = startp + strlen(startp); /* point to end */
StrNCpy(test_path, startp, Min(endp - startp + 1, MAXPGPATH));
if (is_absolute_path(test_path))
join_path_components(retpath, test_path, argv0);
else
{
join_path_components(retpath, cwd, test_path);
join_path_components(retpath, retpath, argv0);
}
canonicalize_path(retpath);
switch (validate_exec(retpath))
{
case 0: /* found ok */
return resolve_symlinks(retpath);
case -1: /* wasn't even a candidate, keep looking */
break;
case -2: /* found but disqualified */
log_error(_("could not read binary \"%s\""),
retpath);
break;
}
} while (*endp);
}
log_error(_("could not find a \"%s\" to execute"), argv0);
return -1;
}
/*
* Entry point of pg_arman command.
*/
int
main(int argc, char *argv[])
{
const char *cmd = NULL;
const char *range1 = NULL;
const char *range2 = NULL;
pgBackupRange range;
int i;
/* do not buffer progress messages */
setvbuf(stdout, 0, _IONBF, 0); /* TODO: remove this */
/* initialize configuration */
catalog_init_config(¤t);
/* overwrite configuration with command line arguments */
i = pgut_getopt(argc, argv, options);
for (; i < argc; i++)
{
if (cmd == NULL)
cmd = argv[i];
else if (range1 == NULL)
range1 = argv[i];
else if (range2 == NULL)
range2 = argv[i];
else
elog(ERROR, "too many arguments");
}
/* command argument (backup/restore/show/...) is required. */
if (cmd == NULL)
{
help(false);
return 1;
}
/* get object range argument if any */
if (range1 && range2)
parse_range(&range, range1, range2);
else if (range1)
parse_range(&range, range1, "");
else
range.begin = range.end = 0;
/* Read default configuration from file. */
if (backup_path)
{
char path[MAXPGPATH];
/* Check if backup_path is directory. */
struct stat stat_buf;
int rc = stat(backup_path, &stat_buf);
/* If rc == -1, there is no file or directory. So it's OK. */
if (rc != -1 && !S_ISDIR(stat_buf.st_mode))
elog(ERROR, "-B, --backup-path must be a path to directory");
join_path_components(path, backup_path, PG_RMAN_INI_FILE);
pgut_readopt(path, options, ERROR);
}
/* BACKUP_PATH is always required */
if (backup_path == NULL)
elog(ERROR, "required parameter not specified: BACKUP_PATH (-B, --backup-path)");
/* path must be absolute */
if (backup_path != NULL && !is_absolute_path(backup_path))
elog(ERROR, "-B, --backup-path must be an absolute path");
if (pgdata != NULL && !is_absolute_path(pgdata))
elog(ERROR, "-D, --pgdata must be an absolute path");
if (arclog_path != NULL && !is_absolute_path(arclog_path))
elog(ERROR, "-A, --arclog-path must be an absolute path");
/* Sanity checks with commands */
if (pg_strcasecmp(cmd, "delete") == 0 && arclog_path == NULL)
elog(ERROR, "delete command needs ARCLOG_PATH (-A, --arclog-path) to be set");
/* setup exclusion list for file search */
for (i = 0; pgdata_exclude[i]; i++) /* find first empty slot */
;
if (arclog_path)
pgdata_exclude[i++] = arclog_path;
/* do actual operation */
if (pg_strcasecmp(cmd, "init") == 0)
return do_init();
else if (pg_strcasecmp(cmd, "backup") == 0)
{
pgBackupOption bkupopt;
int res;
bkupopt.smooth_checkpoint = smooth_checkpoint;
bkupopt.keep_data_generations = keep_data_generations;
bkupopt.keep_data_days = keep_data_days;
/* Do the backup */
res = do_backup(bkupopt);
if (res != 0)
return res;
/* If validation has been requested, do it */
range.begin = current.start_time;
range.end = current.start_time + 1;
if (backup_validate)
do_validate(&range);
}
else if (pg_strcasecmp(cmd, "restore") == 0)
return do_restore(target_time, target_xid,
target_inclusive, target_tli);
else if (pg_strcasecmp(cmd, "show") == 0)
return do_show(&range, show_all);
else if (pg_strcasecmp(cmd, "validate") == 0)
return do_validate(&range);
else if (pg_strcasecmp(cmd, "delete") == 0)
return do_delete(&range);
else
elog(ERROR, "invalid command \"%s\"", cmd);
return 0;
}
