+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <assert.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <ctype.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <time.h>
+#include <sys/wait.h>
+#include <fnmatch.h>
+#include <limits.h>
+
+
+#include "gcc-compat.h"
+#include "cmdline.h"
+#include "log.h"
+#include "string.h"
+#include "error.h"
+#include "fd.h"
+#include "exec.h"
+
+
+struct gengetopt_args_info conf;
+char *dss_error_txt = NULL;
+
+DEFINE_DSS_ERRLIST;
+
+/** Defines one dss command. */
+struct server_command {
+ /** The name of the command. */
+ const char *name;
+ /** Pointer to the function that handles the command. */
+ int (*handler)(int, char * const * const);
+};
+
+/* a litte cpp magic helps to DRY */
+#define SERVER_COMMANDS \
+ SERVER_COMMAND(ls) \
+ SERVER_COMMAND(create) \
+ SERVER_COMMAND(prune) \
+ SERVER_COMMAND(daemon)
+#define SERVER_COMMAND(x) int com_ ##x(int, char * const * const);
+SERVER_COMMANDS
+#undef SERVER_COMMAND
+#define SERVER_COMMAND(x) {.name = #x, .handler = com_ ## x},
+static struct server_command command_list[] = {
+ SERVER_COMMANDS
+ {.name = NULL, .handler = NULL}
+};
+#undef SERVER_COMMAND
+
+/*
+ * complete, not being deleted: 1204565370-1204565371.Sun_Mar_02_2008_14_33-Sun_Mar_02_2008_14_43
+ * complete, being deleted: 1204565370-1204565371.being_deleted
+ * incomplete, not being deleted: 1204565370-incomplete
+ * incomplete, being deleted: 1204565370-incomplete.being_deleted
+ */
+enum snapshot_status_flags {
+ SS_COMPLETE = 1,
+ SS_BEING_DELETED = 2,
+};
+
+struct snapshot {
+ char *name;
+ int64_t creation_time;
+ int64_t completion_time;
+ enum snapshot_status_flags flags;
+ unsigned interval;
+};
+
+int is_snapshot(const char *dirname, int64_t now, struct snapshot *s)
+{
+ int i, ret;
+ char *dash, *dot, *tmp;
+ int64_t num;
+
+ assert(dirname);
+ dash = strchr(dirname, '-');
+ if (!dash || !dash[1] || dash == dirname)
+ return 0;
+ for (i = 0; dirname[i] != '-'; i++)
+ if (!isdigit(dirname[i]))
+ return 0;
+ tmp = dss_strdup(dirname);
+ tmp[i] = '\0';
+ ret = dss_atoi64(tmp, &num);
+ free(tmp);
+ if (ret < 0) {
+ free(dss_error_txt);
+ return 0;
+ }
+ assert(num >= 0);
+ if (num > now)
+ return 0;
+ s->creation_time = num;
+ //DSS_DEBUG_LOG("%s start time: %lli\n", dirname, (long long)s->creation_time);
+ s->interval = (long long) ((now - s->creation_time)
+ / conf.unit_interval_arg / 24 / 3600);
+ if (!strcmp(dash + 1, "incomplete")) {
+ s->completion_time = -1;
+ s->flags = 0; /* neither complete, nor being deleted */
+ goto success;
+ }
+ if (!strcmp(dash + 1, "incomplete.being_deleted")) {
+ s->completion_time = -1;
+ s->flags = SS_BEING_DELETED; /* mot cpmplete, being deleted */
+ goto success;
+ }
+ tmp = dash + 1;
+ dot = strchr(tmp, '.');
+ if (!dot || !dot[1] || dot == tmp)
+ return 0;
+ for (i = 0; tmp[i] != '.'; i++)
+ if (!isdigit(tmp[i]))
+ return 0;
+ tmp = dss_strdup(dash + 1);
+ tmp[i] = '\0';
+ ret = dss_atoi64(tmp, &num);
+ free(tmp);
+ if (ret < 0) {
+ free(dss_error_txt);
+ return 0;
+ }
+ if (num > now)
+ return 0;
+ s->completion_time = num;
+ s->flags = SS_COMPLETE;
+ if (strcmp(dot + 1, "being_deleted"))
+ s->flags |= SS_BEING_DELETED;
+success:
+ s->name = dss_strdup(dirname);
+ return 1;
+}
+
+int64_t get_current_time(void)
+{
+ time_t now;
+ time(&now);
+ DSS_DEBUG_LOG("now: %lli\n", (long long) now);
+ return (int64_t)now;
+}
+
+char *incomplete_name(int64_t start)
+{
+ return make_message("%lli-incomplete", (long long)start);
+}
+
+char *being_deleted_name(struct snapshot *s)
+{
+ if (s->flags & SS_COMPLETE)
+ return make_message("%lli-%lli.being_deleted",
+ (long long)s->creation_time,
+ (long long)s->completion_time);
+ return make_message("%lli-incomplete.being_deleted",
+ (long long)s->creation_time);
+}
+
+int complete_name(int64_t start, int64_t end, char **result)
+{
+ struct tm start_tm, end_tm;
+ time_t *start_seconds = (time_t *) (uint64_t *)&start; /* STFU, gcc */
+ time_t *end_seconds = (time_t *) (uint64_t *)&end; /* STFU, gcc */
+ char start_str[200], end_str[200];
+
+ if (!localtime_r(start_seconds, &start_tm)) {
+ make_err_msg("%lli", (long long)start);
+ return -E_LOCALTIME;
+ }
+ if (!localtime_r(end_seconds, &end_tm)) {
+ make_err_msg("%lli", (long long)end);
+ return -E_LOCALTIME;
+ }
+ if (!strftime(start_str, sizeof(start_str), "%a_%b_%d_%Y_%H_%M_%S", &start_tm)) {
+ make_err_msg("%lli", (long long)start);
+ return -E_STRFTIME;
+ }
+ if (!strftime(end_str, sizeof(end_str), "%a_%b_%d_%Y_%H_%M_%S", &end_tm)) {
+ make_err_msg("%lli", (long long)end);
+ return -E_STRFTIME;
+ }
+ *result = make_message("%lli-%lli.%s-%s", (long long) start, (long long) end,
+ start_str, end_str);
+ return 1;
+}
+
+struct snapshot_list {
+ int64_t now;
+ unsigned num_snapshots;
+ unsigned array_size;
+ struct snapshot **snapshots;
+ /**
+ * Array of size num_intervals + 1
+ *
+ * It contains the number of snapshots in each interval. interval_count[num_intervals]
+ * is the number of snapshots which belong to any interval greater than num_intervals.
+ */
+ unsigned *interval_count;
+};
+
+#define FOR_EACH_SNAPSHOT(s, i, sl) \
+ for ((i) = 0; (i) < (sl)->num_snapshots && ((s) = (sl)->snapshots[(i)]); (i)++)
+
+
+
+#define NUM_COMPARE(x, y) ((int)((x) < (y)) - (int)((x) > (y)))
+
+static int compare_snapshots(const void *a, const void *b)
+{
+ struct snapshot *s1 = *(struct snapshot **)a;
+ struct snapshot *s2 = *(struct snapshot **)b;
+ return NUM_COMPARE(s2->creation_time, s1->creation_time);
+}
+
+/** Compute the minimum of \a a and \a b. */
+#define DSS_MIN(a,b) ((a) < (b) ? (a) : (b))
+
+int add_snapshot(const char *dirname, void *private)
+{
+ struct snapshot_list *sl = private;
+ struct snapshot s;
+ int ret = is_snapshot(dirname, sl->now, &s);
+
+ if (!ret)
+ return 1;
+ if (sl->num_snapshots >= sl->array_size) {
+ sl->array_size = 2 * sl->array_size + 1;
+ sl->snapshots = dss_realloc(sl->snapshots,
+ sl->array_size * sizeof(struct snapshot *));
+ }
+ sl->snapshots[sl->num_snapshots] = dss_malloc(sizeof(struct snapshot));
+ *(sl->snapshots[sl->num_snapshots]) = s;
+ sl->interval_count[DSS_MIN(s.interval, conf.num_intervals_arg)]++;
+ sl->num_snapshots++;
+ return 1;
+}
+
+void get_snapshot_list(struct snapshot_list *sl)
+{
+ sl->now = get_current_time();
+ sl->num_snapshots = 0;
+ sl->array_size = 0;
+ sl->snapshots = NULL;
+ sl->interval_count = dss_calloc((conf.num_intervals_arg + 1) * sizeof(unsigned));
+ for_each_subdir(add_snapshot, sl);
+ qsort(sl->snapshots, sl->num_snapshots, sizeof(struct snapshot *),
+ compare_snapshots);
+}
+
+void free_snapshot_list(struct snapshot_list *sl)
+{
+ int i;
+ struct snapshot *s;
+
+ FOR_EACH_SNAPSHOT(s, i, sl) {
+ free(s->name);
+ free(s);
+ }
+ free(sl->interval_count);
+ free(sl->snapshots);
+}
+
+/**
+ * Print a log message about the exit status of a child.
+ */
+void log_termination_msg(pid_t pid, int status)
+{
+ if (WIFEXITED(status))
+ DSS_INFO_LOG("child %i exited. Exit status: %i\n", (int)pid,
+ WEXITSTATUS(status));
+ else if (WIFSIGNALED(status))
+ DSS_NOTICE_LOG("child %i was killed by signal %i\n", (int)pid,
+ WTERMSIG(status));
+ else
+ DSS_WARNING_LOG("child %i terminated abormally\n", (int)pid);
+}
+
+int wait_for_process(pid_t pid, int *status)
+{
+ int ret;
+
+ DSS_DEBUG_LOG("Waiting for process %d to terminate\n", (int)pid);
+ for (;;) {
+ ret = waitpid(pid, status, 0);
+ if (ret >= 0 || errno != EINTR)
+ break;
+ }
+ if (ret < 0) {
+ ret = -ERRNO_TO_DSS_ERROR(errno);
+ make_err_msg("failed to wait for process %d", (int)pid);
+ } else
+ log_termination_msg(pid, *status);
+ return ret;
+}
+
+int remove_snapshot(struct snapshot *s, pid_t *pid)
+{
+ int fds[3] = {0, 0, 0};
+ char *new_name = being_deleted_name(s);
+ int ret = dss_rename(s->name, new_name);
+ char *argv[] = {"rm", "-rf", new_name, NULL};
+
+ if (ret < 0)
+ goto out;
+ DSS_NOTICE_LOG("removing %s (interval = %i)\n", s->name, s->interval);
+ ret = dss_exec(pid, argv[0], argv, fds);
+out:
+ free(new_name);
+ return ret;
+}
+
+int remove_redundant_snapshot(struct snapshot_list *sl,
+ int dry_run, pid_t *pid)
+{
+ int ret, i, interval;
+ struct snapshot *s;
+ unsigned missing = 0;
+
+ DSS_INFO_LOG("looking for intervals containing too many snapshots\n");
+ for (interval = conf.num_intervals_arg - 1; interval >= 0; interval--) {
+ unsigned keep = 1<<(conf.num_intervals_arg - interval - 1);
+ unsigned num = sl->interval_count[interval];
+ struct snapshot *victim = NULL, *prev = NULL;
+ int64_t score = LONG_MAX;
+
+ if (keep >= num)
+ missing += keep - num;
+ DSS_DEBUG_LOG("interval %i: keep: %u, have: %u, missing: %u\n",
+ interval, keep, num, missing);
+ if (keep + missing >= num)
+ continue;
+ /* redundant snapshot in this interval, pick snapshot with lowest score */
+ FOR_EACH_SNAPSHOT(s, i, sl) {
+ int64_t this_score;
+
+ DSS_DEBUG_LOG("checking %s\n", s->name);
+ if (s->interval > interval) {
+ prev = s;
+ continue;
+ }
+ if (s->interval < interval)
+ break;
+ if (!victim) {
+ victim = s;
+ prev = s;
+ continue;
+ }
+ assert(prev);
+ /* check if s is a better victim */
+ this_score = s->creation_time - prev->creation_time;
+ assert(this_score >= 0);
+ DSS_DEBUG_LOG("%s: score %lli\n", s->name, (long long)score);
+ if (this_score < score) {
+ score = this_score;
+ victim = s;
+ }
+ prev = s;
+ }
+ assert(victim);
+ if (dry_run) {
+ printf("%s would be removed (interval = %i)\n",
+ victim->name, victim->interval);
+ continue;
+ }
+ ret = remove_snapshot(victim, pid);
+ return ret < 0? ret : 1;
+ }
+ return 0;
+}
+
+int remove_old_snapshot(struct snapshot_list *sl, int dry_run, pid_t *pid)
+{
+ int i, ret;
+ struct snapshot *s;
+
+ DSS_INFO_LOG("looking for snapshots belonging to intervals greater than %d\n",
+ conf.num_intervals_arg);
+ FOR_EACH_SNAPSHOT(s, i, sl) {
+ if (s->interval <= conf.num_intervals_arg)
+ continue;
+ if (dry_run) {
+ printf("%s would be removed (interval = %i)\n",
+ s->name, s->interval);
+ continue;
+ }
+ ret = remove_snapshot(s, pid);
+ if (ret < 0)
+ return ret;
+ return 1;
+ }
+ return 0;
+}
+
+int wait_for_rm_process(pid_t pid)
+{
+ int status, es, ret = wait_for_process(pid, &status);
+ if (ret < 0)
+ return ret;
+ if (!WIFEXITED(status)) {
+ ret = E_INVOLUNTARY_EXIT;
+ make_err_msg("rm process %d died involuntary", (int)pid);
+ return ret;
+ }
+ es = WEXITSTATUS(status);
+ if (es) {
+ ret = -E_BAD_EXIT_CODE;
+ make_err_msg("rm process %d returned %d", (int)pid, es);
+ return ret;
+ }
+ return 1;
+}
+
+int com_prune(int argc, char * const * argv)
+{
+ int ret, dry_run = 0;
+ struct snapshot_list sl;
+ pid_t pid;
+
+ if (argc > 2) {
+ make_err_msg("too many arguments");
+ return -E_SYNTAX;
+ }
+ if (argc == 2) {
+ if (strcmp(argv[1], "-d")) {
+ make_err_msg("%s", argv[1]);
+ return -E_SYNTAX;
+ }
+ dry_run = 1;
+ }
+ for (;;) {
+ get_snapshot_list(&sl);
+ ret = remove_old_snapshot(&sl, dry_run, &pid);
+ free_snapshot_list(&sl);
+ if (ret < 0)
+ return ret;
+ if (!ret)
+ break;
+ ret = wait_for_rm_process(pid);
+ if (ret < 0)
+ goto out;
+ }
+ for (;;) {
+ get_snapshot_list(&sl);
+ ret = remove_redundant_snapshot(&sl, dry_run, &pid);
+ free_snapshot_list(&sl);
+ if (ret < 0)
+ return ret;
+ if (!ret)
+ break;
+ ret = wait_for_rm_process(pid);
+ if (ret < 0)
+ goto out;
+ }
+ return 1;
+out:
+ return ret;
+}
+
+struct newest_snapshot_data {
+ char * newest_name;
+ int64_t newest_creation_time;
+ int64_t now;
+};
+
+int get_newest_complete(const char *dirname, void *private)
+{
+ struct newest_snapshot_data *nsd = private;
+ struct snapshot s;
+ int ret = is_snapshot(dirname, nsd->now, &s);
+
+ if (ret <= 0)
+ return 1;
+ if (s.creation_time < nsd->newest_creation_time)
+ return 1;
+ nsd->newest_creation_time = s.creation_time;
+ free(nsd->newest_name);
+ nsd->newest_name = s.name;
+ return 1;
+}
+
+__malloc char *name_of_newest_complete_snapshot(void)
+{
+ struct newest_snapshot_data nsd = {
+ .now = get_current_time(),
+ .newest_creation_time = -1
+ };
+ for_each_subdir(get_newest_complete, &nsd);
+ return nsd.newest_name;
+}
+
+void create_rsync_argv(char ***argv, int64_t *num)
+{
+ char *logname, *newest = name_of_newest_complete_snapshot();
+ int i = 0, j;
+
+ *argv = dss_malloc((15 + conf.rsync_option_given) * sizeof(char *));
+ (*argv)[i++] = dss_strdup("rsync");
+ (*argv)[i++] = dss_strdup("-aq");
+ (*argv)[i++] = dss_strdup("--delete");
+ for (j = 0; j < conf.rsync_option_given; j++)
+ (*argv)[i++] = dss_strdup(conf.rsync_option_arg[j]);
+ if (newest) {
+ DSS_INFO_LOG("using %s as reference snapshot\n", newest);
+ (*argv)[i++] = make_message("--link-dest=../%s", newest);
+ free(newest);
+ } else
+ DSS_INFO_LOG("no previous snapshot found");
+ if (conf.exclude_patterns_given) {
+ (*argv)[i++] = dss_strdup("--exclude-from");
+ (*argv)[i++] = dss_strdup(conf.exclude_patterns_arg);
+
+ }
+ logname = dss_logname();
+ if (conf.remote_user_given && !strcmp(conf.remote_user_arg, logname))
+ (*argv)[i++] = dss_strdup(conf.source_dir_arg);
+ else
+ (*argv)[i++] = make_message("%s@%s:%s/", conf.remote_user_given?
+ conf.remote_user_arg : logname,
+ conf.remote_host_arg, conf.source_dir_arg);
+ free(logname);
+ *num = get_current_time();
+ (*argv)[i++] = incomplete_name(*num);
+ (*argv)[i++] = NULL;
+ for (j = 0; j < i; j++)
+ DSS_DEBUG_LOG("argv[%d] = %s\n", j, (*argv)[j]);
+}
+
+void free_rsync_argv(char **argv)
+{
+ int i;
+ for (i = 0; argv[i]; i++)
+ free(argv[i]);
+ free(argv);
+}
+
+int create_snapshot(char **argv, pid_t *pid)
+{
+ int fds[3] = {0, 0, 0};
+
+ return dss_exec(pid, argv[0], argv, fds);
+}
+
+int rename_incomplete_snapshot(int64_t start)
+{
+ char *old_name, *new_name;
+ int ret;
+
+ ret = complete_name(start, get_current_time(), &new_name);
+ if (ret < 0)
+ return ret;
+ old_name = incomplete_name(start);
+ ret = dss_rename(old_name, new_name);
+ if (ret >= 0)
+ DSS_NOTICE_LOG("%s -> %s\n", old_name, new_name);
+ free(old_name);
+ free(new_name);
+ return ret;
+}
+
+int com_create(int argc, __a_unused char * const * argv)
+{
+ int ret, status, es;
+ char **rsync_argv;
+ int64_t snapshot_num;
+ pid_t pid;
+
+ if (argc != 1) {
+ ret = -E_SYNTAX;
+ make_err_msg("create: no args expected, %d given", argc - 1);
+ return ret;
+ }
+ create_rsync_argv(&rsync_argv, &snapshot_num);
+ DSS_NOTICE_LOG("creating snapshot %lli\n", (long long)snapshot_num);
+ ret = create_snapshot(rsync_argv, &pid);
+ if (ret < 0)
+ goto out;
+ ret = wait_for_process(pid, &status);
+ if (ret < 0)
+ goto out;
+ if (!WIFEXITED(status)) {
+ ret = E_INVOLUNTARY_EXIT;
+ make_err_msg("rsync process %d died involuntary", (int)pid);
+ goto out;
+ }
+ es = WEXITSTATUS(status);
+ if (es != 0 && es != 23 && es != 24) {
+ ret = -E_BAD_EXIT_CODE;
+ make_err_msg("rsync process %d returned %d", (int)pid, es);
+ goto out;
+ }
+ ret = rename_incomplete_snapshot(snapshot_num);
+out:
+ free_rsync_argv(rsync_argv);
+ return ret;
+}
+
+int com_ls(int argc, __a_unused char * const * argv)
+{
+ int i, ret;
+ struct snapshot_list sl;
+ struct snapshot *s;
+ if (argc != 1) {
+ ret = -E_SYNTAX;
+ make_err_msg("ls: no args expected, %d given", argc - 1);
+ return ret;
+ }
+ get_snapshot_list(&sl);
+ FOR_EACH_SNAPSHOT(s, i, &sl)
+ printf("%u\t%s\n", s->interval, s->name);
+ free_snapshot_list(&sl);
+ return 1;
+}
+
+/* TODO: Unlink pid file */
+__noreturn void clean_exit(int status)
+{
+ //kill(0, SIGTERM);
+ free(dss_error_txt);
+ exit(status);
+}
+
+__printf_2_3 void dss_log(int ll, const char* fmt,...)
+{
+ va_list argp;
+ if (ll < conf.loglevel_arg)
+ return;
+ va_start(argp, fmt);
+ vfprintf(stderr, fmt, argp);
+ va_end(argp);
+}
+
+int read_config_file(void)
+{
+ int ret;
+ char *config_file;
+ struct stat statbuf;
+
+ if (conf.config_file_given)
+ config_file = dss_strdup(conf.config_file_arg);
+ else {
+ char *home = get_homedir();
+ config_file = make_message("%s/.dssrc", home);
+ free(home);
+ }
+ ret = stat(config_file, &statbuf);
+ if (ret && conf.config_file_given) {
+ ret = -ERRNO_TO_DSS_ERROR(errno);
+ make_err_msg("failed to stat config file %s", config_file);
+ goto out;
+ }
+ if (!ret) {
+ struct cmdline_parser_params params = {
+ .override = 0,
+ .initialize = 0,
+ .check_required = 0,
+ .check_ambiguity = 0
+ };
+ cmdline_parser_config_file(config_file, &conf, ¶ms);
+ }
+ if (!conf.source_dir_given || !conf.dest_dir_given) {
+ ret = -E_SYNTAX;
+ make_err_msg("you need to specify both source_dir and dest_dir");
+ goto out;
+ }
+ ret = 1;
+out:
+ free(config_file);
+ return ret;
+}
+
+int check_config(void)
+{
+ if (conf.unit_interval_arg <= 0) {
+ make_err_msg("bad unit interval: %i", conf.unit_interval_arg);
+ return -E_INVALID_NUMBER;
+ }
+ DSS_DEBUG_LOG("unit interval: %i day(s)\n", conf.unit_interval_arg);
+ if (conf.num_intervals_arg <= 0) {
+ make_err_msg("bad number of intervals %i", conf.num_intervals_arg);
+ return -E_INVALID_NUMBER;
+ }
+ DSS_DEBUG_LOG("number of intervals: %i\n", conf.num_intervals_arg);
+ return 1;
+}
+
+int main(int argc, char **argv)
+{
+ int i, ret;
+
+ cmdline_parser(argc, argv, &conf); /* aborts on errors */
+ if (!conf.inputs_num) {
+ ret = -E_SYNTAX;
+ make_err_msg("no command given");
+ goto out;
+ }
+ ret = read_config_file();
+ if (ret < 0)
+ goto out;
+ ret = check_config();
+ if (ret < 0)
+ goto out;
+ ret = dss_chdir(conf.dest_dir_arg);
+ if (ret < 0)
+ goto out;
+ for (i = 0; command_list[i].name; i++) {
+ if (strcmp(command_list[i].name, conf.inputs[0]))
+ continue;
+ ret = command_list[i].handler(conf.inputs_num, conf.inputs);
+ goto out;
+ }
+ ret = -E_INVALID_COMMAND;
+ make_err_msg("%s", conf.inputs[0]);
+out:
+ if (ret < 0)
+ log_err_msg(EMERG, -ret);
+ clean_exit(ret >= 0? EXIT_SUCCESS : EXIT_FAILURE);
+}