terom@24: 
terom@24: /*
terom@24:  * A simple PostgreSQL-based filesystem.
terom@24:  */
terom@24: 
terom@24: #include <string.h>
terom@24: #include <errno.h>
terom@24: 
terom@24: #include <event2/event.h>
terom@24: 
terom@24: #include "evfuse.h"
terom@24: #include "evsql.h"
terom@24: #include "dirbuf.h"
terom@24: #include "lib/log.h"
terom@24: #include "lib/signals.h"
terom@24: #include "lib/misc.h"
terom@24: 
terom@24: #define SERROR(val) do { (val); goto error; } while(0)
terom@24: 
terom@24: struct dbfs {
terom@24:     struct event_base *ev_base;
terom@24:     struct signals *signals;
terom@24:     
terom@24:     const char *db_conninfo;
terom@24:     struct evsql *db;
terom@24: 
terom@24:     struct evfuse *ev_fuse;
terom@24: };
terom@24: 
terom@24: #define CONNINFO_DEFAULT "dbname=test"
terom@24: 
terom@24: // XXX: not sure how this should work
terom@24: #define CACHE_TIMEOUT 1.0
terom@24: 
terom@24: mode_t _dbfs_mode (const char *type) {
terom@24:     if (!strcmp(type, "DIR"))
terom@24:         return S_IFDIR;
terom@24: 
terom@24:     if (!strcmp(type, "REG"))
terom@24:         return S_IFREG;
terom@24: 
terom@24:     else {
terom@24:         WARNING("[dbfs] weird mode-type: %s", type);
terom@24:         return 0;
terom@24:     }
terom@24: }
terom@24: 
terom@24: void dbfs_init (void *userdata, struct fuse_conn_info *conn) {
terom@24:     INFO("[dbfs.init] userdata=%p, conn=%p", userdata, conn);
terom@24: 
terom@24: }
terom@24: 
terom@24: void dbfs_destroy (void *userdata) {
terom@24:     INFO("[dbfs.destroy] userdata=%p", userdata);
terom@24: 
terom@24: 
terom@24: }
terom@24: 
terom@25: /*
terom@25:  * Check the result set.
terom@25:  *
terom@25:  * Returns;
terom@25:  *  -1  if the query failed, the columns do not match, or there are too many/few rows
terom@25:  *  0   the results match
terom@25:  *  1   there were no results
terom@25:  */
terom@25: int _dbfs_check_res (const struct evsql_result_info *res, size_t rows, size_t cols) {
terom@25:     int err = 0;
terom@25: 
terom@25:     // check if it failed
terom@25:     if (res->error)
terom@25:         NERROR(evsql_result_error(res));
terom@25:         
terom@25:     // not found?
terom@25:     if (evsql_result_rows(res) == 0)
terom@25:         SERROR(err = 1);
terom@25: 
terom@25:     // duplicate rows?
terom@25:     if (evsql_result_rows(res) != rows)
terom@25:         ERROR("multiple rows returned");
terom@25:     
terom@25:     // correct number of columns
terom@25:     if (evsql_result_cols(res) != 5)
terom@25:         ERROR("wrong number of columns: %zu", evsql_result_cols(res));
terom@25: 
terom@25:     // good
terom@25:     return 0;
terom@25: 
terom@25: error:
terom@25:     if (!err)
terom@25:         err = -1;
terom@25: 
terom@25:     return err;
terom@25: }
terom@25: 
terom@25: int _dbfs_stat_info (struct stat *st, const struct evsql_result_info *res, size_t row, size_t col_offset) {
terom@25:     int err = 0;
terom@25:     
terom@25:     uint16_t mode;
terom@25:     uint64_t size, nlink;
terom@25:     const char *type;
terom@25:     
terom@25:     // extract the data
terom@25:     if (0
terom@25:         ||  evsql_result_string(res, row, col_offset + 0, &type,       0 ) // inodes.type
terom@25:         ||  evsql_result_uint16(res, row, col_offset + 1, &mode,       0 ) // inodes.mode
terom@25:         ||  evsql_result_uint64(res, row, col_offset + 2, &size,       0 ) // inodes.size
terom@25:         ||  evsql_result_uint64(res, row, col_offset + 3, &nlink,      0 ) // count(*)
terom@25:     )
terom@25:         EERROR(err = EIO, "invalid db data");
terom@25: 
terom@25:     INFO("\tst_mode=S_IF%s | %ho, st_nlink=%llu, st_size=%llu", type, mode, (long long unsigned int) nlink, (long long unsigned int) size);
terom@25: 
terom@25:     // convert and store
terom@25:     st->st_mode = _dbfs_mode(type) | mode;
terom@25:     st->st_nlink = nlink;
terom@25:     st->st_size = size;
terom@25:     
terom@25:     // good
terom@25:     return 0;
terom@25: 
terom@25: error:
terom@25:     return -1;
terom@25: }
terom@25: 
terom@24: void _dbfs_lookup_result (const struct evsql_result_info *res, void *arg) {
terom@24:     struct fuse_req *req = arg;
terom@24:     struct fuse_entry_param e; ZINIT(e);
terom@24:     int err = 0;
terom@24:     
terom@24:     uint32_t ino;
terom@24:     
terom@25:     // check the results
terom@25:     if ((err = _dbfs_check_res(res, 1, 5)))
terom@25:         SERROR(err = (err ==  1 ? ENOENT : EIO));
terom@24:     
terom@24:     // get the data
terom@24:     if (0
terom@24:         ||  evsql_result_uint32(res, 0, 0, &ino,        0 ) // inodes.ino
terom@24:     )
terom@24:         EERROR(err = EIO, "invalid db data");
terom@25:         
terom@25:     INFO("[dbfs.lookup] -> ion=%u", ino);
terom@24:     
terom@25:     // stat attrs
terom@25:     if (_dbfs_stat_info(&e.attr, res, 0, 1))
terom@25:         goto error;
terom@24: 
terom@25:     // other attrs
terom@24:     e.ino = e.attr.st_ino = ino;
terom@24:     e.attr_timeout = CACHE_TIMEOUT;
terom@24:     e.entry_timeout = CACHE_TIMEOUT;
terom@24:         
terom@24:     // reply
terom@24:     if ((err = fuse_reply_entry(req, &e)))
terom@24:         EERROR(err, "fuse_reply_entry");
terom@24: 
terom@24: error:
terom@24:     if (err && (err = fuse_reply_err(req, err)))
terom@24:         EWARNING(err, "fuse_reply_err");
terom@24: 
terom@24:     // free
terom@24:     evsql_result_free(res);
terom@24: }
terom@24: 
terom@24: void dbfs_lookup (struct fuse_req *req, fuse_ino_t parent, const char *name) {
terom@24:     struct dbfs *ctx = fuse_req_userdata(req);
terom@24:     int err;
terom@24: 
terom@24:     INFO("[dbfs.lookup] parent=%lu name=%s", parent, name);
terom@24:     
terom@24:     // query and params
terom@24:     const char *sql = 
terom@24:         "SELECT"
terom@24:         " inodes.ino, inodes.type, inodes.mode, inodes.size, count(*)"
terom@24:         " FROM file_tree INNER JOIN inodes ON (file_tree.inode = inodes.ino)"
terom@25:         " WHERE file_tree.parent = $1::int4 AND file_tree.name = $2::varchar"
terom@24:         " GROUP BY inodes.ino, inodes.type, inodes.mode, inodes.size";
terom@24:     
terom@24:     static struct evsql_query_params params = EVSQL_PARAMS(EVSQL_FMT_BINARY) {
terom@24:         EVSQL_PARAM ( UINT32 ),
terom@24:         EVSQL_PARAM ( STRING ),
terom@24: 
terom@24:         EVSQL_PARAMS_END
terom@24:     };
terom@24:     
terom@24:     // build params
terom@24:     if (0
terom@24:         ||  evsql_param_uint32(&params, 0, parent)
terom@24:         ||  evsql_param_string(&params, 1, name)
terom@24:     )
terom@24:         EERROR(err = EIO, "evsql_param_*");
terom@24: 
terom@24:     // query
terom@25:     if (evsql_query_params(ctx->db, NULL, sql, &params, _dbfs_lookup_result, req) == NULL)
terom@24:         EERROR(err = EIO, "evsql_query_params");
terom@24: 
terom@24:     // XXX: handle interrupts
terom@24:     
terom@24:     // wait
terom@24:     return;
terom@24: 
terom@24: error:
terom@24:     if ((err = fuse_reply_err(req, err)))
terom@24:         EWARNING(err, "fuse_reply_err");
terom@24: }
terom@24: 
terom@25: void _dbfs_getattr_result (const struct evsql_result_info *res, void *arg) {
terom@25:     struct fuse_req *req = arg;
terom@25:     struct stat st; ZINIT(st);
terom@25:     int err = 0;
terom@25:     
terom@25:     // check the results
terom@25:     if ((err = _dbfs_check_res(res, 1, 4)))
terom@25:         SERROR(err = (err ==  1 ? ENOENT : EIO));
terom@25:         
terom@25:     INFO("[dbfs.getattr %p] -> (stat follows)", req);
terom@25:     
terom@25:     // stat attrs
terom@25:     if (_dbfs_stat_info(&st, res, 0, 0))
terom@25:         goto error;
terom@25: 
terom@25:     // XXX: we don't have the ino
terom@25:     st.st_ino = 0;
terom@25: 
terom@25:     // reply
terom@25:     if ((err = fuse_reply_attr(req, &st, CACHE_TIMEOUT)))
terom@25:         EERROR(err, "fuse_reply_entry");
terom@25: 
terom@25: error:
terom@25:     if (err && (err = fuse_reply_err(req, err)))
terom@25:         EWARNING(err, "fuse_reply_err");
terom@25: 
terom@25:     // free
terom@25:     evsql_result_free(res);
terom@25: }
terom@25: 
terom@25: static void dbfs_getattr (struct fuse_req *req, fuse_ino_t ino, struct fuse_file_info *fi) {
terom@25:     struct dbfs *ctx = fuse_req_userdata(req);
terom@25:     int err;
terom@25:     
terom@25:     (void) fi;
terom@25: 
terom@25:     INFO("[dbfs.getattr %p] ino=%lu", req, ino);
terom@25: 
terom@25:     const char *sql =
terom@25:         "SELECT"
terom@25:         " inodes.type, inodes.mode, inodes.size, count(*)"
terom@25:         " FROM inodes"
terom@25:         " WHERE inodes.ino = ‰1::int4"
terom@25:         " GROUP BY inodes.type, inodes.mode, inodes.size";
terom@25: 
terom@25:     static struct evsql_query_params params = EVSQL_PARAMS(EVSQL_FMT_BINARY) {
terom@25:         EVSQL_PARAM ( UINT32 ),
terom@25: 
terom@25:         EVSQL_PARAMS_END
terom@25:     };
terom@25: 
terom@25:     // build params
terom@25:     if (0
terom@25:         ||  evsql_param_uint32(&params, 0, ino)
terom@25:     )
terom@25:         SERROR(err = EIO);
terom@25:         
terom@25:     // query
terom@25:     if (evsql_query_params(ctx->db, NULL, sql, &params, _dbfs_getattr_result, req) == NULL)
terom@25:         SERROR(err = EIO);
terom@25: 
terom@25:     // XXX: handle interrupts
terom@25:     
terom@25:     // wait
terom@25:     return;
terom@25: 
terom@25: error:
terom@25:     if ((err = fuse_reply_err(req, err)))
terom@25:         EWARNING(err, "fuse_reply_err");
terom@25: }
terom@25: 
terom@24: struct fuse_lowlevel_ops dbfs_llops = {
terom@25: 
terom@24:     .init           = dbfs_init,
terom@24:     .destroy        = dbfs_destroy,
terom@24:     
terom@24:     .lookup         = dbfs_lookup,
terom@25: 
terom@25:     .getattr        = dbfs_getattr,
terom@24: };
terom@24: 
terom@24: void dbfs_sql_error (struct evsql *evsql, void *arg) {
terom@24:     struct dbfs *ctx = arg;
terom@24: 
terom@24:     // AAAAAAAAAA.... panic
terom@24:     WARNING("[dbfs] SQL error: BREAKING MAIN LOOP LIEK NAO");
terom@24: 
terom@24:     event_base_loopbreak(ctx->ev_base);
terom@24: }
terom@24: 
terom@24: int main (int argc, char **argv) {
terom@24:     struct fuse_args fuse_args = FUSE_ARGS_INIT(argc, argv);
terom@24:     struct dbfs ctx; ZINIT(ctx);
terom@24:     
terom@24:     // parse args, XXX: fuse_args
terom@24:     ctx.db_conninfo = CONNINFO_DEFAULT;
terom@24:     
terom@24:     // init libevent
terom@24:     if ((ctx.ev_base = event_base_new()) == NULL)
terom@24:         ERROR("event_base_new");
terom@24:     
terom@24:     // setup signals
terom@24:     if ((ctx.signals = signals_default(ctx.ev_base)) == NULL)
terom@24:         ERROR("signals_default");
terom@24: 
terom@24:     // open sql
terom@24:     if ((ctx.db = evsql_new_pq(ctx.ev_base, ctx.db_conninfo, dbfs_sql_error, &ctx)) == NULL)
terom@24:         ERROR("evsql_new_pq");
terom@24: 
terom@24:     // open fuse
terom@24:     if ((ctx.ev_fuse = evfuse_new(ctx.ev_base, &fuse_args, &dbfs_llops, &ctx)) == NULL)
terom@24:         ERROR("evfuse_new");
terom@24: 
terom@24:     // run libevent
terom@24:     INFO("running libevent loop");
terom@24: 
terom@24:     if (event_base_dispatch(ctx.ev_base))
terom@24:         PERROR("event_base_dispatch");
terom@24:     
terom@24:     // clean shutdown
terom@24: 
terom@24: error :
terom@24:     // cleanup
terom@24:     if (ctx.ev_fuse)
terom@24:         evfuse_close(ctx.ev_fuse);
terom@24: 
terom@24:     // XXX: ctx.db
terom@24:     
terom@24:     if (ctx.signals)
terom@24:         signals_free(ctx.signals);
terom@24: 
terom@24:     if (ctx.ev_base)
terom@24:         event_base_free(ctx.ev_base);
terom@24:     
terom@24:     fuse_opt_free_args(&fuse_args);
terom@24: }
terom@24: