path: root/lib/libalpm/diskspace.c

/*
 *  diskspace.c
 *
 *  Copyright (c) 2010-2016 Pacman Development Team <pacman-dev@archlinux.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <errno.h>

#if defined(HAVE_MNTENT_H)
#include <mntent.h>
#endif
#if defined(HAVE_SYS_MNTTAB_H)
#include <sys/mnttab.h>
#endif
#if defined(HAVE_SYS_STATVFS_H)
#include <sys/statvfs.h>
#endif
#if defined(HAVE_SYS_PARAM_H)
#include <sys/param.h>
#endif
#if defined(HAVE_SYS_MOUNT_H)
#include <sys/mount.h>
#endif
#if defined(HAVE_SYS_UCRED_H)
#include <sys/ucred.h>
#endif
#if defined(HAVE_SYS_TYPES_H)
#include <sys/types.h>
#endif

/* libalpm */
#include "diskspace.h"
#include "alpm_list.h"
#include "util.h"
#include "log.h"
#include "trans.h"
#include "handle.h"

static int mount_point_cmp(const void *p1, const void *p2)
{
        const alpm_mountpoint_t *mp1 = p1;
        const alpm_mountpoint_t *mp2 = p2;
        /* the negation will sort all mountpoints before their parent */
        return -strcmp(mp1->mount_dir, mp2->mount_dir);
}

static void mount_point_list_free(alpm_list_t *mount_points)
{
        alpm_list_t *i;

        for(i = mount_points; i; i = i->next) {
                alpm_mountpoint_t *data = i->data;
                FREE(data->mount_dir);
        }
        FREELIST(mount_points);
}

static int mount_point_load_fsinfo(alpm_handle_t *handle, alpm_mountpoint_t *mountpoint)
{
#if defined(HAVE_GETMNTENT)
        /* grab the filesystem usage */
        if(statvfs(mountpoint->mount_dir, &(mountpoint->fsp)) != 0) {
                _alpm_log(handle, ALPM_LOG_WARNING,
                                _("could not get filesystem information for %s: %s\n"),
                                mountpoint->mount_dir, strerror(errno));
                mountpoint->fsinfo_loaded = MOUNT_FSINFO_FAIL;
                return -1;
        }

        _alpm_log(handle, ALPM_LOG_DEBUG, "loading fsinfo for %s\n", mountpoint->mount_dir);
        mountpoint->read_only = mountpoint->fsp.f_flag & ST_RDONLY;
        mountpoint->fsinfo_loaded = MOUNT_FSINFO_LOADED;
#else
        (void)handle;
        (void)mountpoint;
#endif

        return 0;
}

static alpm_list_t *mount_point_list(alpm_handle_t *handle)
{
        alpm_list_t *mount_points = NULL, *ptr;
        alpm_mountpoint_t *mp;

#if defined(HAVE_GETMNTENT) && defined(HAVE_MNTENT_H)
        /* Linux */
        struct mntent *mnt;
        FILE *fp;

        fp = setmntent(MOUNTED, "r");

        if(fp == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not open file: %s: %s\n"),
                                MOUNTED, strerror(errno));
                return NULL;
        }

        while((mnt = getmntent(fp))) {
                CALLOC(mp, 1, sizeof(alpm_mountpoint_t), RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                STRDUP(mp->mount_dir, mnt->mnt_dir, free(mp); RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                mp->mount_dir_len = strlen(mp->mount_dir);

                mount_points = alpm_list_add(mount_points, mp);
        }

        endmntent(fp);
#elif defined(HAVE_GETMNTENT) && defined(HAVE_MNTTAB_H)
        /* Solaris, Illumos */
        struct mnttab mnt;
        FILE *fp;
        int ret;

        fp = fopen("/etc/mnttab", "r");

        if(fp == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not open file %s: %s\n"),
                                "/etc/mnttab", strerror(errno));
                return NULL;
        }

        while((ret = getmntent(fp, &mnt)) == 0) {
                CALLOC(mp, 1, sizeof(alpm_mountpoint_t), RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                STRDUP(mp->mount_dir, mnt->mnt_mountp,  free(mp); RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                mp->mount_dir_len = strlen(mp->mount_dir);

                mount_points = alpm_list_add(mount_points, mp);
        }
        /* -1 == EOF */
        if(ret != -1) {
                _alpm_log(handle, ALPM_LOG_WARNING,
                                _("could not get filesystem information\n"));
        }

        fclose(fp);
#elif defined(HAVE_GETMNTINFO)
        /* FreeBSD (statfs), NetBSD (statvfs), OpenBSD (statfs), OS X (statfs) */
        int entries;
        FSSTATSTYPE *fsp;

        entries = getmntinfo(&fsp, MNT_NOWAIT);

        if(entries < 0) {
                _alpm_log(handle, ALPM_LOG_ERROR,
                                _("could not get filesystem information\n"));
                return NULL;
        }

        for(; entries-- > 0; fsp++) {
                CALLOC(mp, 1, sizeof(alpm_mountpoint_t), RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                STRDUP(mp->mount_dir, fsp->f_mntonname, free(mp); RET_ERR(handle, ALPM_ERR_MEMORY, NULL));
                mp->mount_dir_len = strlen(mp->mount_dir);
                memcpy(&(mp->fsp), fsp, sizeof(FSSTATSTYPE));
#if defined(HAVE_GETMNTINFO_STATVFS) && defined(HAVE_STRUCT_STATVFS_F_FLAG)
                mp->read_only = fsp->f_flag & ST_RDONLY;
#elif defined(HAVE_GETMNTINFO_STATFS) && defined(HAVE_STRUCT_STATFS_F_FLAGS)
                mp->read_only = fsp->f_flags & MNT_RDONLY;
#endif

                /* we don't support lazy loading on this platform */
                mp->fsinfo_loaded = MOUNT_FSINFO_LOADED;

                mount_points = alpm_list_add(mount_points, mp);
        }
#endif

        mount_points = alpm_list_msort(mount_points, alpm_list_count(mount_points),
                        mount_point_cmp);
        for(ptr = mount_points; ptr != NULL; ptr = ptr->next) {
                mp = ptr->data;
                _alpm_log(handle, ALPM_LOG_DEBUG, "discovered mountpoint: %s\n", mp->mount_dir);
        }
        return mount_points;
}

static alpm_mountpoint_t *match_mount_point(const alpm_list_t *mount_points,
                const char *real_path)
{
        const alpm_list_t *mp;

        for(mp = mount_points; mp != NULL; mp = mp->next) {
                alpm_mountpoint_t *data = mp->data;

                /* first, check if the prefix matches */
                if(strncmp(data->mount_dir, real_path, data->mount_dir_len) == 0) {
                        /* now, the hard work- a file like '/etc/myconfig' shouldn't map to a
                         * mountpoint '/e', but only '/etc'. If the mountpoint ends in a trailing
                         * slash, we know we didn't have a mismatch, otherwise we have to do some
                         * more sanity checks. */
                        if(data->mount_dir[data->mount_dir_len - 1] == '/') {
                                return data;
                        } else if(strlen(real_path) >= data->mount_dir_len) {
                                const char next = real_path[data->mount_dir_len];
                                if(next == '/' || next == '\0') {
                                        return data;
                                }
                        }
                }
        }

        /* should not get here... */
        return NULL;
}

static int calculate_removed_size(alpm_handle_t *handle,
                const alpm_list_t *mount_points, alpm_pkg_t *pkg)
{
        size_t i;
        alpm_filelist_t *filelist = alpm_pkg_get_files(pkg);

        if(!filelist->count) {
                return 0;
        }

        for(i = 0; i < filelist->count; i++) {
                const alpm_file_t *file = filelist->files + i;
                alpm_mountpoint_t *mp;
                struct stat st;
                char path[PATH_MAX];
                blkcnt_t remove_size;
                const char *filename = file->name;

                snprintf(path, PATH_MAX, "%s%s", handle->root, filename);

                if(llstat(path, &st) == -1) {
                        if(alpm_option_match_noextract(handle, filename)) {
                                _alpm_log(handle, ALPM_LOG_WARNING,
                                                _("could not get file information for %s\n"), filename);
                        }
                        continue;
                }

                /* skip directories and symlinks to be consistent with libarchive that
                 * reports them to be zero size */
                if(S_ISDIR(st.st_mode) || S_ISLNK(st.st_mode)) {
                        continue;
                }

                mp = match_mount_point(mount_points, path);
                if(mp == NULL) {
                        _alpm_log(handle, ALPM_LOG_WARNING,
                                        _("could not determine mount point for file %s\n"), filename);
                        continue;
                }

                /* don't check a mount that we know we can't stat */
                if(mp && mp->fsinfo_loaded == MOUNT_FSINFO_FAIL) {
                        continue;
                }

                /* lazy load filesystem info */
                if(mp->fsinfo_loaded == MOUNT_FSINFO_UNLOADED) {
                        if(mount_point_load_fsinfo(handle, mp) < 0) {
                                continue;
                        }
                }

                /* the addition of (divisor - 1) performs ceil() with integer division */
                remove_size = (st.st_size + mp->fsp.f_bsize - 1) / mp->fsp.f_bsize;
                mp->blocks_needed -= remove_size;
                mp->used |= USED_REMOVE;
        }

        return 0;
}

static int calculate_installed_size(alpm_handle_t *handle,
                const alpm_list_t *mount_points, alpm_pkg_t *pkg)
{
        size_t i;
        alpm_filelist_t *filelist = alpm_pkg_get_files(pkg);

        if(!filelist->count) {
                return 0;
        }

        for(i = 0; i < filelist->count; i++) {
                const alpm_file_t *file = filelist->files + i;
                alpm_mountpoint_t *mp;
                char path[PATH_MAX];
                blkcnt_t install_size;
                const char *filename = file->name;

                /* libarchive reports these as zero size anyways */
                /* NOTE: if we do start accounting for directory size, a dir matching a
                 * mountpoint needs to be attributed to the parent, not the mountpoint. */
                if(S_ISDIR(file->mode) || S_ISLNK(file->mode)) {
                        continue;
                }

                /* approximate space requirements for db entries */
                if(filename[0] == '.') {
                        filename = handle->dbpath;
                }

                snprintf(path, PATH_MAX, "%s%s", handle->root, filename);

                mp = match_mount_point(mount_points, path);
                if(mp == NULL) {
                        _alpm_log(handle, ALPM_LOG_WARNING,
                                        _("could not determine mount point for file %s\n"), filename);
                        continue;
                }

                /* don't check a mount that we know we can't stat */
                if(mp && mp->fsinfo_loaded == MOUNT_FSINFO_FAIL) {
                        continue;
                }

                /* lazy load filesystem info */
                if(mp->fsinfo_loaded == MOUNT_FSINFO_UNLOADED) {
                        if(mount_point_load_fsinfo(handle, mp) < 0) {
                                continue;
                        }
                }

                /* the addition of (divisor - 1) performs ceil() with integer division */
                install_size = (file->size + mp->fsp.f_bsize - 1) / mp->fsp.f_bsize;
                mp->blocks_needed += install_size;
                mp->used |= USED_INSTALL;
        }

        return 0;
}

static int check_mountpoint(alpm_handle_t *handle, alpm_mountpoint_t *mp)
{
        /* cushion is roughly min(5% capacity, 20MiB) */
        fsblkcnt_t fivepc = (mp->fsp.f_blocks / 20) + 1;
        fsblkcnt_t twentymb = (20 * 1024 * 1024 / mp->fsp.f_bsize) + 1;
        fsblkcnt_t cushion = fivepc < twentymb ? fivepc : twentymb;
        blkcnt_t needed = mp->max_blocks_needed + cushion;

        _alpm_log(handle, ALPM_LOG_DEBUG,
                        "partition %s, needed %jd, cushion %ju, free %ju\n",
                        mp->mount_dir, (intmax_t)mp->max_blocks_needed,
                        (uintmax_t)cushion, (uintmax_t)mp->fsp.f_bfree);
        if(needed >= 0 && (fsblkcnt_t)needed > mp->fsp.f_bfree) {
                _alpm_log(handle, ALPM_LOG_ERROR,
                                _("Partition %s too full: %jd blocks needed, %ju blocks free\n"),
                                mp->mount_dir, (intmax_t)needed, (uintmax_t)mp->fsp.f_bfree);
                return 1;
        }
        return 0;
}

int _alpm_check_downloadspace(alpm_handle_t *handle, const char *cachedir,
                size_t num_files, off_t *file_sizes)
{
        alpm_list_t *mount_points;
        alpm_mountpoint_t *cachedir_mp;
        char resolved_cachedir[PATH_MAX];
        size_t j;
        int error = 0;

        /* resolve the cachedir path to ensure we check the right mountpoint. We
         * handle failures silently, and continue to use the possibly unresolved
         * path. */
        if(realpath(cachedir, resolved_cachedir) != NULL) {
                cachedir = resolved_cachedir;
        }

        mount_points = mount_point_list(handle);
        if(mount_points == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not determine filesystem mount points\n"));
                return -1;
        }

        cachedir_mp = match_mount_point(mount_points, cachedir);
        if(cachedir_mp == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not determine cachedir mount point %s\n"),
                                cachedir);
                error = 1;
                goto finish;
        }

        if(cachedir_mp->fsinfo_loaded == MOUNT_FSINFO_UNLOADED) {
                if(mount_point_load_fsinfo(handle, cachedir_mp)) {
                        error = 1;
                        goto finish;
                }
        }

        /* there's no need to check for a R/O mounted filesystem here, as
         * _alpm_filecache_setup will never give us a non-writable directory */

        /* round up the size of each file to the nearest block and accumulate */
        for(j = 0; j < num_files; j++) {
                cachedir_mp->max_blocks_needed += (file_sizes[j] + cachedir_mp->fsp.f_bsize + 1) /
                        cachedir_mp->fsp.f_bsize;
        }

        if(check_mountpoint(handle, cachedir_mp)) {
                error = 1;
        }

finish:
        mount_point_list_free(mount_points);

        if(error) {
                RET_ERR(handle, ALPM_ERR_DISK_SPACE, -1);
        }

        return 0;
}

int _alpm_check_diskspace(alpm_handle_t *handle)
{
        alpm_list_t *mount_points, *i;
        alpm_mountpoint_t *root_mp;
        size_t replaces = 0, current = 0, numtargs;
        int error = 0;
        alpm_list_t *targ;
        alpm_trans_t *trans = handle->trans;

        numtargs = alpm_list_count(trans->add);
        mount_points = mount_point_list(handle);
        if(mount_points == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not determine filesystem mount points\n"));
                return -1;
        }
        root_mp = match_mount_point(mount_points, handle->root);
        if(root_mp == NULL) {
                _alpm_log(handle, ALPM_LOG_ERROR, _("could not determine root mount point %s\n"),
                                handle->root);
                error = 1;
                goto finish;
        }

        replaces = alpm_list_count(trans->remove);
        if(replaces) {
                numtargs += replaces;
                for(targ = trans->remove; targ; targ = targ->next, current++) {
                        alpm_pkg_t *local_pkg;
                        int percent = (current * 100) / numtargs;
                        PROGRESS(handle, ALPM_PROGRESS_DISKSPACE_START, "", percent,
                                        numtargs, current);

                        local_pkg = targ->data;
                        calculate_removed_size(handle, mount_points, local_pkg);
                }
        }

        for(targ = trans->add; targ; targ = targ->next, current++) {
                alpm_pkg_t *pkg, *local_pkg;
                int percent = (current * 100) / numtargs;
                PROGRESS(handle, ALPM_PROGRESS_DISKSPACE_START, "", percent,
                                numtargs, current);

                pkg = targ->data;
                /* is this package already installed? */
                local_pkg = _alpm_db_get_pkgfromcache(handle->db_local, pkg->name);
                if(local_pkg) {
                        calculate_removed_size(handle, mount_points, local_pkg);
                }
                calculate_installed_size(handle, mount_points, pkg);

                for(i = mount_points; i; i = i->next) {
                        alpm_mountpoint_t *data = i->data;
                        if(data->blocks_needed > data->max_blocks_needed) {
                                data->max_blocks_needed = data->blocks_needed;
                        }
                }
        }

        PROGRESS(handle, ALPM_PROGRESS_DISKSPACE_START, "", 100,
                        numtargs, current);

        for(i = mount_points; i; i = i->next) {
                alpm_mountpoint_t *data = i->data;
                if(data->used && data->read_only) {
                        _alpm_log(handle, ALPM_LOG_ERROR, _("Partition %s is mounted read only\n"),
                                        data->mount_dir);
                        error = 1;
                } else if(data->used & USED_INSTALL && check_mountpoint(handle, data)) {
                        error = 1;
                }
        }

finish:
        mount_point_list_free(mount_points);

        if(error) {
                RET_ERR(handle, ALPM_ERR_DISK_SPACE, -1);
        }

        return 0;
}

/* vim: set noet: */