[dragonfly.git] / sbin / hammer / cmd_cleanup.c

/*
 * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
 * 
 * This code is derived from software contributed to The DragonFly Project
 * by Matthew Dillon <dillon@backplane.com>
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name of The DragonFly Project nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific, prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * 
 * $DragonFly: src/sbin/hammer/cmd_cleanup.c,v 1.4.2.2 2008/09/25 01:39:33 dillon Exp $
 */
/*
 * Clean up a specific HAMMER filesystem or all HAMMER filesystems.
 *
 * Each filesystem is expected to have a <mount>/snapshots directory.
 * No cleanup will be performed on any filesystem that does not.  If
 * no filesystems are specified the 'df' program is run and any HAMMER
 * or null-mounted hammer PFS's are extracted.
 *
 * The snapshots directory may contain a config file called 'config'.  If
 * no config file is present one will be created with the following
 * defaults:
 *
 *      snapshots 1d 60d        (0d 60d for /tmp, /var/tmp, /usr/obj)
 *      prune     1d 5m
 *      reblock   1d 5m
 *      recopy    30d 5m
 *
 * All hammer commands create and maintain cycle files in the snapshots
 * directory.
 */

#include "hammer.h"

struct didpfs {
        struct didpfs *next;
        uuid_t          uuid;
};

static void do_cleanup(const char *path);
static int strtosecs(char *ptr);
static const char *dividing_slash(const char *path);
static int check_period(const char *snapshots_path, const char *cmd, int arg1,
                        time_t *savep);
static void save_period(const char *snapshots_path, const char *cmd,
                        time_t savet);
static int check_softlinks(const char *snapshots_path);
static void cleanup_softlinks(const char *path, const char *snapshots_path,
                        int arg2);
static int check_expired(const char *fpath, int arg2);

static int cleanup_snapshots(const char *path, const char *snapshots_path,
                              int arg1, int arg2);
static int cleanup_prune(const char *path, const char *snapshots_path,
                              int arg1, int arg2, int snapshots_disabled);
static int cleanup_reblock(const char *path, const char *snapshots_path,
                              int arg1, int arg2);
static int cleanup_recopy(const char *path, const char *snapshots_path,
                              int arg1, int arg2);

static void runcmd(int *resp, const char *ctl, ...);

#define WS      " \t\r\n"

struct didpfs *FirstPFS;

void
hammer_cmd_cleanup(char **av, int ac)
{
        FILE *fp;
        char *ptr;
        char *path;
        char buf[256];

        tzset();
        if (ac == 0) {
                fp = popen("df -t hammer,null", "r");
                if (fp == NULL)
                        errx(1, "hammer cleanup: 'df' failed");
                while (fgets(buf, sizeof(buf), fp) != NULL) {
                        ptr = strtok(buf, WS);
                        if (ptr && strcmp(ptr, "Filesystem") == 0)
                                continue;
                        if (ptr)
                                ptr = strtok(NULL, WS);
                        if (ptr)
                                ptr = strtok(NULL, WS);
                        if (ptr)
                                ptr = strtok(NULL, WS);
                        if (ptr)
                                ptr = strtok(NULL, WS);
                        if (ptr) {
                                path = strtok(NULL, WS);
                                if (path)
                                        do_cleanup(path);
                        }
                }
                fclose(fp);
        } else {
                while (ac) {
                        do_cleanup(*av);
                        --ac;
                        ++av;
                }
        }
}

static
void
do_cleanup(const char *path)
{
        struct hammer_ioc_pseudofs_rw pfs;
        union hammer_ioc_mrecord_any mrec_tmp;
        char *snapshots_path;
        char *config_path;
        struct stat st;
        char *cmd;
        char *ptr;
        int arg1;
        int arg2;
        time_t savet;
        char buf[256];
        FILE *fp;
        struct didpfs *didpfs;
        int snapshots_disabled = 0;
        int prune_warning = 0;
        int fd;
        int r;

        bzero(&pfs, sizeof(pfs));
        bzero(&mrec_tmp, sizeof(mrec_tmp));
        pfs.ondisk = &mrec_tmp.pfs.pfsd;
        pfs.bytes = sizeof(mrec_tmp.pfs.pfsd);
        pfs.pfs_id = -1;

        printf("cleanup %-20s -", path);
        fd = open(path, O_RDONLY);
        if (fd < 0) {
                printf(" unable to access directory: %s\n", strerror(errno));
                return;
        }
        if (ioctl(fd, HAMMERIOC_GET_PSEUDOFS, &pfs) != 0) {
                printf(" not a HAMMER filesystem: %s\n", strerror(errno));
                return;
        }
        close(fd);
        if (pfs.version != HAMMER_IOC_PSEUDOFS_VERSION) {
                printf(" unrecognized HAMMER version\n");
                return;
        }

        /*
         * Make sure we have not already handled this PFS.  Several nullfs
         * mounts might alias the same PFS.
         */
        for (didpfs = FirstPFS; didpfs; didpfs = didpfs->next) {
                if (bcmp(&didpfs->uuid, &mrec_tmp.pfs.pfsd.unique_uuid, sizeof(uuid_t)) == 0) {
                        printf(" pfs_id %d already handled\n", pfs.pfs_id);
                        return;
                }
        }
        didpfs = malloc(sizeof(*didpfs));
        didpfs->next = FirstPFS;
        FirstPFS = didpfs;
        didpfs->uuid = mrec_tmp.pfs.pfsd.unique_uuid;

        /*
         * Figure out where the snapshot directory is.
         */
        if (mrec_tmp.pfs.pfsd.snapshots[0] == '/') {
                asprintf(&snapshots_path, "%s", mrec_tmp.pfs.pfsd.snapshots);
        } else if (mrec_tmp.pfs.pfsd.snapshots[0]) {
                printf(" WARNING: pfs-slave's snapshots dir is not absolute\n");
                return;
        } else if (mrec_tmp.pfs.pfsd.mirror_flags & HAMMER_PFSD_SLAVE) {
                printf(" WARNING: must configure snapshot dir for PFS slave\n");
                printf("\tWe suggest <fs>/var/slaves/<name> where "
                       "<fs> is the base HAMMER fs\n");
                printf("\tContaining the slave\n");
                return;
        } else {
                asprintf(&snapshots_path,
                         "%s%ssnapshots", path, dividing_slash(path));
        }

        /*
         * Create a snapshot directory if necessary, and a config file if
         * necessary.
         */
        if (stat(snapshots_path, &st) < 0) {
                if (mkdir(snapshots_path, 0755) != 0) {
                        free(snapshots_path);
                        printf(" unable to create snapshot dir \"%s\": %s\n",
                                snapshots_path, strerror(errno));
                        return;
                }
        }
        asprintf(&config_path, "%s/config", snapshots_path);
        if ((fp = fopen(config_path, "r")) == NULL) {
                fp = fopen(config_path, "w");
                if (fp == NULL) {
                        printf(" cannot create %s: %s\n",
                                config_path, strerror(errno));
                        return;
                }
                if (strcmp(path, "/tmp") == 0 ||
                    strcmp(path, "/var/tmp") == 0 ||
                    strcmp(path, "/usr/obj") == 0) {
                        fprintf(fp, "snapshots 0d 60d\n");
                } else {
                        fprintf(fp, "snapshots 1d 60d\n");
                }
                fprintf(fp, 
                        "prune     1d 5m\n"
                        "reblock   1d 5m\n"
                        "recopy    30d 10m\n");
                fclose(fp);
                fp = fopen(config_path, "r");
        }
        if (fp == NULL) {
                printf(" cannot access %s: %s\n",
                       config_path, strerror(errno));
                return;
        }

        printf(" handle PFS #%d using %s\n", pfs.pfs_id, snapshots_path);

        /*
         * Process the config file
         */
        while (fgets(buf, sizeof(buf), fp) != NULL) {
                cmd = strtok(buf, WS);
                arg1 = 0;
                arg2 = 0;
                if ((ptr = strtok(NULL, WS)) != NULL) {
                        arg1 = strtosecs(ptr);
                        if ((ptr = strtok(NULL, WS)) != NULL)
                                arg2 = strtosecs(ptr);
                }

                printf("%20s - ", cmd);
                fflush(stdout);

                if (arg1 == 0) {
                        printf("disabled\n");
                        if (strcmp(cmd, "snapshots") == 0) {
                                if (check_softlinks(snapshots_path))
                                        prune_warning = 1;
                                else
                                        snapshots_disabled = 1;
                        }
                        continue;
                }

                r = 1;
                if (strcmp(cmd, "snapshots") == 0) {
                        if (check_period(snapshots_path, cmd, arg1, &savet)) {
                                printf("run\n");
                                cleanup_softlinks(path, snapshots_path, arg2);
                                r = cleanup_snapshots(path, snapshots_path,
                                                  arg1, arg2);
                        } else {
                                printf("skip\n");
                        }
                } else if (strcmp(cmd, "prune") == 0) {
                        if (check_period(snapshots_path, cmd, arg1, &savet)) {
                                if (prune_warning)
                                        printf("run - WARNING snapshot softlinks present but snapshots disabled\n");
                                else
                                        printf("run\n");
                                r = cleanup_prune(path, snapshots_path,
                                              arg1, arg2, snapshots_disabled);
                        } else {
                                printf("skip\n");
                        }
                } else if (strcmp(cmd, "reblock") == 0) {
                        if (check_period(snapshots_path, cmd, arg1, &savet)) {
                                printf("run");
                                fflush(stdout);
                                if (VerboseOpt)
                                        printf("\n");
                                r = cleanup_reblock(path, snapshots_path,
                                                arg1, arg2);
                        } else {
                                printf("skip\n");
                        }
                } else if (strcmp(cmd, "recopy") == 0) {
                        if (check_period(snapshots_path, cmd, arg1, &savet)) {
                                printf("run");
                                fflush(stdout);
                                if (VerboseOpt)
                                        printf("\n");
                                r = cleanup_recopy(path, snapshots_path,
                                               arg1, arg2);
                        } else {
                                printf("skip\n");
                        }
                } else {
                        printf("unknown directive\n");
                        r = 1;
                }
                if (r == 0)
                        save_period(snapshots_path, cmd, savet);
        }
        fclose(fp);
        usleep(1000);
}

static
int
strtosecs(char *ptr)
{
        int val;

        val = strtol(ptr, &ptr, 0);
        switch(*ptr) {
        case 'd':
                val *= 24;
                /* fall through */
        case 'h':
                val *= 60;
                /* fall through */
        case 'm':
                val *= 60;
                /* fall through */
        case 's':
                break;
        default:
                errx(1, "illegal suffix converting %s\n", ptr);
                break;
        }
        return(val);
}

static const char *
dividing_slash(const char *path)
{
        int len = strlen(path);
        if (len && path[len-1] == '/')
                return("");
        else
                return("/");
}

/*
 * Check whether the desired period has elapsed since the last successful
 * run.  The run may take a while and cross a boundary so we remember the
 * current time_t so we can save it later on.
 *
 * Periods in minutes, hours, or days are assumed to have been crossed
 * if the local time crosses a minute, hour, or day boundary regardless
 * of how close the last operation actually was.
 */
static int
check_period(const char *snapshots_path, const char *cmd, int arg1,
        time_t *savep)
{
        char *check_path;
        struct tm tp1;
        struct tm tp2;
        FILE *fp;
        time_t baset, lastt;
        char buf[256];

        time(savep);
        localtime_r(savep, &tp1);

        /*
         * Retrieve the start time of the last successful operation.
         */
        asprintf(&check_path, "%s/.%s.period", snapshots_path, cmd);
        fp = fopen(check_path, "r");
        free(check_path);
        if (fp == NULL)
                return(1);
        if (fgets(buf, sizeof(buf), fp) == NULL) {
                fclose(fp);
                return(1);
        }
        fclose(fp);

        lastt = strtol(buf, NULL, 0);
        localtime_r(&lastt, &tp2);

        /*
         * Normalize the times.  e.g. if asked to do something on a 1-day
         * interval the operation will be performed as soon as the day
         * turns over relative to the previous operation, even if the previous
         * operation ran a few seconds ago just before midnight.
         */
        if (arg1 % 60 == 0) {
                tp1.tm_sec = 0;
                tp2.tm_sec = 0;
        }
        if (arg1 % (60 * 60) == 0) {
                tp1.tm_min = 0;
                tp2.tm_min = 0;
        }
        if (arg1 % (24 * 60 * 60) == 0) {
                tp1.tm_hour = 0;
                tp2.tm_hour = 0;
        }

        baset = mktime(&tp1);
        lastt = mktime(&tp2);

#if 0
        printf("%lld vs %lld\n", (long long)(baset - lastt), (long long)arg1);
#endif

        if ((int)(baset - lastt) >= arg1)
                return(1);
        return(0);
}

/*
 * Store the start time of the last successful operation.
 */
static void
save_period(const char *snapshots_path, const char *cmd,
                        time_t savet)
{
        char *ocheck_path;
        char *ncheck_path;
        FILE *fp;

        asprintf(&ocheck_path, "%s/.%s.period", snapshots_path, cmd);
        asprintf(&ncheck_path, "%s/.%s.period.new", snapshots_path, cmd);
        fp = fopen(ncheck_path, "w");
        fprintf(fp, "0x%08llx\n", (long long)savet);
        if (fclose(fp) == 0)
                rename(ncheck_path, ocheck_path);
        remove(ncheck_path);
}

/*
 * Simply count the number of softlinks in the snapshots dir
 */
static int
check_softlinks(const char *snapshots_path)
{
        struct dirent *den;
        struct stat st;
        DIR *dir;
        char *fpath;
        int res = 0;

        if ((dir = opendir(snapshots_path)) != NULL) {
                while ((den = readdir(dir)) != NULL) {
                        if (den->d_name[0] == '.')
                                continue;
                        asprintf(&fpath, "%s/%s", snapshots_path, den->d_name);
                        if (lstat(fpath, &st) == 0 && S_ISLNK(st.st_mode))
                                ++res;
                        free(fpath);
                }
                closedir(dir);
        }
        return(res);
}

/*
 * Clean up expired softlinks in the snapshots dir
 */
static void
cleanup_softlinks(const char *path __unused, const char *snapshots_path, int arg2)
{
        struct dirent *den;
        struct stat st;
        DIR *dir;
        char *fpath;

        if ((dir = opendir(snapshots_path)) != NULL) {
                while ((den = readdir(dir)) != NULL) {
                        if (den->d_name[0] == '.')
                                continue;
                        asprintf(&fpath, "%s/%s", snapshots_path, den->d_name);
                        if (lstat(fpath, &st) == 0 && S_ISLNK(st.st_mode) &&
                            strncmp(den->d_name, "snap-", 5) == 0) {
                                if (check_expired(den->d_name, arg2)) {
                                        if (VerboseOpt) {
                                                printf("    expire %s\n",
                                                        fpath);
                                        }
                                        remove(fpath);
                                }
                        }
                        free(fpath);
                }
                closedir(dir);
        }
}

/*
 * Take a softlink path in the form snap-yyyymmdd-hhmm and the
 * expiration in seconds (arg2) and return non-zero if the softlink
 * has expired.
 */
static int
check_expired(const char *fpath, int arg2)
{
        struct tm tm;
        time_t t;
        int year;
        int month;
        int day;
        int hour;
        int minute;
        int r;

        r = sscanf(fpath, "snap-%4d%2d%2d-%2d%2d",
                   &year, &month, &day, &hour, &minute);
        if (r == 5) {
                bzero(&tm, sizeof(tm));
                tm.tm_isdst = -1;
                tm.tm_min = minute;
                tm.tm_hour = hour;
                tm.tm_mday = day;
                tm.tm_mon = month - 1;
                tm.tm_year = year - 1900;
                t = time(NULL) - mktime(&tm);
                if ((int)t > arg2)
                        return(1);
        }
        return(0);
}

/*
 * Issue a snapshot.
 */
static int
cleanup_snapshots(const char *path __unused, const char *snapshots_path,
                  int arg1 __unused, int arg2 __unused)
{
        int r;

        runcmd(&r, "hammer snapshot %s %s", path, snapshots_path);
        return(r);
}

static int
cleanup_prune(const char *path __unused, const char *snapshots_path,
                  int arg1 __unused, int arg2, int snapshots_disabled)
{
        /*
         * If snapshots have been disabled run prune-everything instead
         * of prune.
         */
        if (snapshots_disabled && arg2) {
                runcmd(NULL, "hammer -c %s/.prune.cycle -t %d prune-everything %s",
                        snapshots_path, arg2, path);
        } else if (snapshots_disabled) {
                runcmd(NULL, "hammer prune-everything %s", path);
        } else if (arg2) {
                runcmd(NULL, "hammer -c %s/.prune.cycle -t %d prune %s",
                        snapshots_path, arg2, snapshots_path);
        } else {
                runcmd(NULL, "hammer prune %s", snapshots_path);
        }
        return(0);
}

static int
cleanup_reblock(const char *path, const char *snapshots_path,
                  int arg1 __unused, int arg2)
{
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.reblock-1.cycle -t %d reblock-btree %s 95",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.reblock-2.cycle -t %d reblock-inodes %s 95",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.reblock-3.cycle -t %d reblock-data %s 95",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0)
                printf("\n");
        return(0);
}

static int
cleanup_recopy(const char *path, const char *snapshots_path,
                  int arg1 __unused, int arg2)
{
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.recopy-1.cycle -t %d reblock-btree %s",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.recopy-2.cycle -t %d reblock-inodes %s",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0) {
                printf(".");
                fflush(stdout);
        }
        runcmd(NULL,
               "hammer -c %s/.recopy-3.cycle -t %d reblock-data %s",
               snapshots_path, arg2, path);
        if (VerboseOpt == 0)
                printf("\n");
        return(0);
}

static
void
runcmd(int *resp, const char *ctl, ...)
{
        va_list va;
        char *cmd;
        char *arg;
        char **av;
        int n;
        int nmax;
        int res;
        pid_t pid;

        /*
         * Generate the command
         */
        va_start(va, ctl);
        vasprintf(&cmd, ctl, va);
        va_end(va);
        if (VerboseOpt)
                printf("    %s\n", cmd);

        /*
         * Break us down into arguments.  We do not just use system() here
         * because it blocks SIGINT and friends.
         */
        n = 0;
        nmax = 16;
        av = malloc(sizeof(char *) * nmax);

        for (arg = strtok(cmd, WS); arg; arg = strtok(NULL, WS)) {
                if (n == nmax - 1) {
                        nmax += 16;
                        av = realloc(av, sizeof(char *) * nmax);
                }
                av[n++] = arg;
        }
        av[n++] = NULL;

        /*
         * Run the command.
         */
        if ((pid = fork()) == 0) {
                if (VerboseOpt < 2) {
                        int fd = open("/dev/null", O_RDWR);
                        dup2(fd, 1);
                        close(fd);
                }
                execvp(av[0], av);
                _exit(127);
        } else if (pid < 0) {
                res = 127;
        } else {
                int status;
                while (waitpid(pid, &status, 0) != pid)
                        ;
                res = WEXITSTATUS(status);
        }

        free(cmd);
        free(av);
        if (resp)
                *resp = res;
}