/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996, 1997, 1998
 *      Sleepycat Software.  All rights reserved.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)db_appinit.c  10.66 (Sleepycat) 12/7/98";
#endif /* not lint */

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>

#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#endif

#include "db_int.h"
#include "shqueue.h"
#include "db_page.h"
#include "btree.h"
#include "hash.h"
#include "log.h"
#include "txn.h"
#include "clib_ext.h"
#include "common_ext.h"

static int __db_home __P((DB_ENV *, const char *, u_int32_t));
static int __db_parse __P((DB_ENV *, char *));
static int __db_tmp_open __P((DB_ENV *, u_int32_t, char *, int *));

/*
 * This conflict array is used for concurrent db access (cdb).  It
 * uses the same locks as the db_rw_conflict array, but adds an IW
 * mode to be used for write cursors.
 */
static u_int8_t const db_cdb_conflicts[] = {
        /*              N   R   W  IW */
        /*    N */      0,  0,  0,  0,
        /*    R */      0,  0,  1,  0,
        /*    W */      0,  1,  1,  1,
        /*   IW */      0,  0,  1,  1
};

/*
 * db_version --
 *      Return version information.
 */
char *
db_version(majverp, minverp, patchp)
        int *majverp, *minverp, *patchp;
{
        if (majverp != NULL)
                *majverp = DB_VERSION_MAJOR;
        if (minverp != NULL)
                *minverp = DB_VERSION_MINOR;
        if (patchp != NULL)
                *patchp = DB_VERSION_PATCH;
        return ((char *)DB_VERSION_STRING);
}

/*
 * db_appinit --
 *      Initialize the application environment.
 */
int
db_appinit(db_home, db_config, dbenv, flags)
        const char *db_home;
        char * const *db_config;
        DB_ENV *dbenv;
        u_int32_t flags;
{
        FILE *fp;
        int mode, ret;
        char * const *p;
        char *lp, buf[MAXPATHLEN * 2];

        fp = NULL;

        /* Validate arguments. */
        if (dbenv == NULL)
                return (EINVAL);

#ifdef HAVE_SPINLOCKS
#define OKFLAGS                                                         \
    (DB_CREATE | DB_INIT_CDB | DB_INIT_LOCK | DB_INIT_LOG |             \
    DB_INIT_MPOOL | DB_INIT_TXN | DB_MPOOL_PRIVATE | DB_NOMMAP |        \
    DB_RECOVER | DB_RECOVER_FATAL | DB_THREAD | DB_TXN_NOSYNC |         \
    DB_USE_ENVIRON | DB_USE_ENVIRON_ROOT)
#else
#define OKFLAGS                                                         \
    (DB_CREATE | DB_INIT_CDB | DB_INIT_LOCK | DB_INIT_LOG |             \
    DB_INIT_MPOOL | DB_INIT_TXN | DB_MPOOL_PRIVATE | DB_NOMMAP |        \
    DB_RECOVER | DB_RECOVER_FATAL | DB_TXN_NOSYNC |                     \
    DB_USE_ENVIRON | DB_USE_ENVIRON_ROOT)
#endif
        if ((ret = __db_fchk(dbenv, "db_appinit", flags, OKFLAGS)) != 0)
                return (ret);

        /* Transactions imply logging. */
        if (LF_ISSET(DB_INIT_TXN))
                LF_SET(DB_INIT_LOG);

        /* Convert the db_appinit(3) flags. */
        if (LF_ISSET(DB_THREAD))
                F_SET(dbenv, DB_ENV_THREAD);

        /* Set the database home. */
        if ((ret = __db_home(dbenv, db_home, flags)) != 0)
                goto err;

        /* Parse the config array. */
        for (p = db_config; p != NULL && *p != NULL; ++p)
                if ((ret = __db_parse(dbenv, *p)) != 0)
                        goto err;

        /*
         * Parse the config file.
         *
         * XXX
         * Don't use sprintf(3)/snprintf(3) -- the former is dangerous, and
         * the latter isn't standard, and we're manipulating strings handed
         * us by the application.
         */
        if (dbenv->db_home != NULL) {
#define CONFIG_NAME     "/DB_CONFIG"
                if (strlen(dbenv->db_home) +
                    strlen(CONFIG_NAME) + 1 > sizeof(buf)) {
                        ret = ENAMETOOLONG;
                        goto err;
                }
                (void)strcpy(buf, dbenv->db_home);
                (void)strcat(buf, CONFIG_NAME);
                if ((fp = fopen(buf, "r")) != NULL) {
                        while (fgets(buf, sizeof(buf), fp) != NULL) {
                                if ((lp = strchr(buf, '\n')) == NULL) {
                                        __db_err(dbenv,
                                            "%s: line too long", CONFIG_NAME);
                                        ret = EINVAL;
                                        goto err;
                                }
                                *lp = '\0';
                                if (buf[0] == '\0' ||
                                    buf[0] == '#' || isspace(buf[0]))
                                        continue;

                                if ((ret = __db_parse(dbenv, buf)) != 0)
                                        goto err;
                        }
                        (void)fclose(fp);
                        fp = NULL;
                }
        }

        /* Set up the tmp directory path. */
        if (dbenv->db_tmp_dir == NULL && (ret = __os_tmpdir(dbenv, flags)) != 0)
                goto err;

        /*
         * Flag that the structure has been initialized by the application.
         * Note, this must be set before calling into the subsystems as it
         * is used when we're doing file naming.
         */
        F_SET(dbenv, DB_ENV_APPINIT);

        /*
         * If we are doing recovery, remove all the old shared memory
         * regions.
         */
        if (LF_ISSET(DB_RECOVER | DB_RECOVER_FATAL)) {
                if ((ret = log_unlink(NULL, 1, dbenv)) != 0)
                        goto err;
                if ((ret = memp_unlink(NULL, 1, dbenv)) != 0)
                        goto err;
                if ((ret = lock_unlink(NULL, 1, dbenv)) != 0)
                        goto err;
                if ((ret = txn_unlink(NULL, 1, dbenv)) != 0)
                        goto err;
        }

        /*
         * Create the new shared regions.
         *
         * Default permissions are read-write for both owner and group.
         */
        mode = __db_omode("rwrw--");
        if (LF_ISSET(DB_INIT_CDB)) {
                if (LF_ISSET(DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_TXN)) {
                        ret = EINVAL;
                        goto err;
                }
                F_SET(dbenv, DB_ENV_CDB);
                dbenv->lk_conflicts = db_cdb_conflicts;
                dbenv->lk_modes = DB_LOCK_RW_N + 1;
                if ((ret = lock_open(NULL, LF_ISSET(DB_CREATE | DB_THREAD),
                    mode, dbenv, &dbenv->lk_info)) != 0)
                        goto err;
        }
        if (LF_ISSET(DB_INIT_LOCK) && (ret = lock_open(NULL,
            LF_ISSET(DB_CREATE | DB_THREAD),
            mode, dbenv, &dbenv->lk_info)) != 0)
                goto err;
        if (LF_ISSET(DB_INIT_LOG) && (ret = log_open(NULL,
            LF_ISSET(DB_CREATE | DB_THREAD),
            mode, dbenv, &dbenv->lg_info)) != 0)
                goto err;
        if (LF_ISSET(DB_INIT_MPOOL) && (ret = memp_open(NULL,
            LF_ISSET(DB_CREATE | DB_MPOOL_PRIVATE | DB_NOMMAP | DB_THREAD),
            mode, dbenv, &dbenv->mp_info)) != 0)
                goto err;
        if (LF_ISSET(DB_INIT_TXN) && (ret = txn_open(NULL,
            LF_ISSET(DB_CREATE | DB_THREAD | DB_TXN_NOSYNC),
            mode, dbenv, &dbenv->tx_info)) != 0)
                goto err;

        /*
         * If the application is running with transactions, initialize the
         * function tables.  Once that's done, do recovery for any previous
         * run.
         */
        if (LF_ISSET(DB_INIT_TXN)) {
                if ((ret = __bam_init_recover(dbenv)) != 0)
                        goto err;
                if ((ret = __db_init_recover(dbenv)) != 0)
                        goto err;
                if ((ret = __ham_init_recover(dbenv)) != 0)
                        goto err;
                if ((ret = __log_init_recover(dbenv)) != 0)
                        goto err;
                if ((ret = __txn_init_recover(dbenv)) != 0)
                        goto err;

                if (LF_ISSET(DB_RECOVER | DB_RECOVER_FATAL) &&
                    (ret = __db_apprec(dbenv,
                    LF_ISSET(DB_RECOVER | DB_RECOVER_FATAL))) != 0)
                        goto err;
        }

        return (ret);

err:    if (fp != NULL)
                (void)fclose(fp);

        (void)db_appexit(dbenv);
        return (ret);
}

/*
 * db_appexit --
 *      Close down the default application environment.
 */
int
db_appexit(dbenv)
        DB_ENV *dbenv;
{
        int ret, t_ret;
        char **p;

        ret = 0;

        /* Close subsystems. */
        if (dbenv->tx_info && (t_ret = txn_close(dbenv->tx_info)) != 0)
                if (ret == 0)
                        ret = t_ret;
        if (dbenv->lg_info && (t_ret = log_close(dbenv->lg_info)) != 0)
                if (ret == 0)
                        ret = t_ret;
        if (dbenv->mp_info && (t_ret = memp_close(dbenv->mp_info)) != 0)
                if (ret == 0)
                        ret = t_ret;
        if (dbenv->lk_info && (t_ret = lock_close(dbenv->lk_info)) != 0)
                if (ret == 0)
                        ret = t_ret;

        /* Clear initialized flag (after subsystems, it affects naming). */
        F_CLR(dbenv, DB_ENV_APPINIT);

        /* Free allocated memory. */
        if (dbenv->db_home != NULL)
                __os_freestr(dbenv->db_home);
        if ((p = dbenv->db_data_dir) != NULL) {
                for (; *p != NULL; ++p)
                        __os_freestr(*p);
                __os_free(dbenv->db_data_dir,
                    dbenv->data_cnt * sizeof(char **));
        }
        if (dbenv->db_log_dir != NULL)
                __os_freestr(dbenv->db_log_dir);
        if (dbenv->db_tmp_dir != NULL)
                __os_freestr(dbenv->db_tmp_dir);

        return (ret);
}

#define DB_ADDSTR(str) {                                                \
        if ((str) != NULL) {                                            \
                /* If leading slash, start over. */                     \
                if (__os_abspath(str)) {                                \
                        p = start;                                      \
                        slash = 0;                                      \
                }                                                       \
                /* Append to the current string. */                     \
                len = strlen(str);                                      \
                if (slash)                                              \
                        *p++ = PATH_SEPARATOR[0];                       \
                memcpy(p, str, len);                                    \
                p += len;                                               \
                slash = strchr(PATH_SEPARATOR, p[-1]) == NULL;          \
        }                                                               \
}

/*
 * __db_appname --
 *      Given an optional DB environment, directory and file name and type
 *      of call, build a path based on the db_appinit(3) rules, and return
 *      it in allocated space.
 *
 * PUBLIC: int __db_appname __P((DB_ENV *,
 * PUBLIC:    APPNAME, const char *, const char *, u_int32_t, int *, char **));
 */
int
__db_appname(dbenv, appname, dir, file, tmp_oflags, fdp, namep)
        DB_ENV *dbenv;
        APPNAME appname;
        const char *dir, *file;
        u_int32_t tmp_oflags;
        int *fdp;
        char **namep;
{
        DB_ENV etmp;
        size_t len;
        int data_entry, ret, slash, tmp_create, tmp_free;
        const char *a, *b, *c;
        char *p, *start;

        a = b = c = NULL;
        data_entry = -1;
        tmp_create = tmp_free = 0;

        /*
         * We don't return a name when creating temporary files, just an fd.
         * Default to error now.
         */
        if (fdp != NULL)
                *fdp = -1;
        if (namep != NULL)
                *namep = NULL;

        /*
         * Absolute path names are never modified.  If the file is an absolute
         * path, we're done.  If the directory is, simply append the file and
         * return.
         */
        if (file != NULL && __os_abspath(file))
                return (__os_strdup(file, namep));
        if (dir != NULL && __os_abspath(dir)) {
                a = dir;
                goto done;
        }

        /*
         * DB_ENV  DIR     APPNAME         RESULT
         * -------------------------------------------
         * null    null    none            <tmp>/file
         * null    set     none            DIR/file
         * set     null    none            DB_HOME/file
         * set     set     none            DB_HOME/DIR/file
         *
         * DB_ENV  FILE    APPNAME         RESULT
         * -------------------------------------------
         * null    null    DB_APP_DATA     <tmp>/<create>
         * null    set     DB_APP_DATA     ./file
         * set     null    DB_APP_DATA     <tmp>/<create>
         * set     set     DB_APP_DATA     DB_HOME/DB_DATA_DIR/file
         *
         * DB_ENV  DIR     APPNAME         RESULT
         * -------------------------------------------
         * null    null    DB_APP_LOG      <tmp>/file
         * null    set     DB_APP_LOG      DIR/file
         * set     null    DB_APP_LOG      DB_HOME/DB_LOG_DIR/file
         * set     set     DB_APP_LOG      DB_HOME/DB_LOG_DIR/DIR/file
         *
         * DB_ENV          APPNAME         RESULT
         * -------------------------------------------
         * null            DB_APP_TMP*     <tmp>/<create>
         * set             DB_APP_TMP*     DB_HOME/DB_TMP_DIR/<create>
         */
retry:  switch (appname) {
        case DB_APP_NONE:
                if (dbenv == NULL || !F_ISSET(dbenv, DB_ENV_APPINIT)) {
                        if (dir == NULL)
                                goto tmp;
                        a = dir;
                } else {
                        a = dbenv->db_home;
                        b = dir;
                }
                break;
        case DB_APP_DATA:
                if (dir != NULL) {
                        __db_err(dbenv,
                            "DB_APP_DATA: illegal directory specification");
                        return (EINVAL);
                }

                if (file == NULL) {
                        tmp_create = 1;
                        goto tmp;
                }
                if (dbenv == NULL || !F_ISSET(dbenv, DB_ENV_APPINIT))
                        a = PATH_DOT;
                else {
                        a = dbenv->db_home;
                        if (dbenv->db_data_dir != NULL &&
                            (b = dbenv->db_data_dir[++data_entry]) == NULL) {
                                data_entry = -1;
                                b = dbenv->db_data_dir[0];
                        }
                }
                break;
        case DB_APP_LOG:
                if (dbenv == NULL || !F_ISSET(dbenv, DB_ENV_APPINIT)) {
                        if (dir == NULL)
                                goto tmp;
                        a = dir;
                } else {
                        a = dbenv->db_home;
                        b = dbenv->db_log_dir;
                        c = dir;
                }
                break;
        case DB_APP_TMP:
                if (dir != NULL || file != NULL) {
                        __db_err(dbenv,
                    "DB_APP_TMP: illegal directory or file specification");
                        return (EINVAL);
                }

                tmp_create = 1;
                if (dbenv == NULL || !F_ISSET(dbenv, DB_ENV_APPINIT))
                        goto tmp;
                else {
                        a = dbenv->db_home;
                        b = dbenv->db_tmp_dir;
                }
                break;
        }

        /* Reference a file from the appropriate temporary directory. */
        if (0) {
tmp:            if (dbenv == NULL || !F_ISSET(dbenv, DB_ENV_APPINIT)) {
                        memset(&etmp, 0, sizeof(etmp));
                        if ((ret = __os_tmpdir(&etmp, DB_USE_ENVIRON)) != 0)
                                return (ret);
                        tmp_free = 1;
                        a = etmp.db_tmp_dir;
                } else
                        a = dbenv->db_tmp_dir;
        }

done:   len =
            (a == NULL ? 0 : strlen(a) + 1) +
            (b == NULL ? 0 : strlen(b) + 1) +
            (c == NULL ? 0 : strlen(c) + 1) +
            (file == NULL ? 0 : strlen(file) + 1);

        /*
         * Allocate space to hold the current path information, as well as any
         * temporary space that we're going to need to create a temporary file
         * name.
         */
#define DB_TRAIL        "XXXXXX"
        if ((ret =
            __os_malloc(len + sizeof(DB_TRAIL) + 10, NULL, &start)) != 0) {
                if (tmp_free)
                        __os_freestr(etmp.db_tmp_dir);
                return (ret);
        }

        slash = 0;
        p = start;
        DB_ADDSTR(a);
        DB_ADDSTR(b);
        DB_ADDSTR(file);
        *p = '\0';

        /* Discard any space allocated to find the temp directory. */
        if (tmp_free) {
                __os_freestr(etmp.db_tmp_dir);
                tmp_free = 0;
        }

        /*
         * If we're opening a data file, see if it exists.  If it does,
         * return it, otherwise, try and find another one to open.
         */
        if (data_entry != -1 && __os_exists(start, NULL) != 0) {
                __os_freestr(start);
                a = b = c = NULL;
                goto retry;
        }

        /* Create the file if so requested. */
        if (tmp_create &&
            (ret = __db_tmp_open(dbenv, tmp_oflags, start, fdp)) != 0) {
                __os_freestr(start);
                return (ret);
        }

        if (namep == NULL)
                __os_freestr(start);
        else
                *namep = start;
        return (0);
}

/*
 * __db_home --
 *      Find the database home.
 */
static int
__db_home(dbenv, db_home, flags)
        DB_ENV *dbenv;
        const char *db_home;
        u_int32_t flags;
{
        const char *p;

        p = db_home;

        /* Use the environment if it's permitted and initialized. */
#ifdef HAVE_GETUID
        if (LF_ISSET(DB_USE_ENVIRON) ||
            (LF_ISSET(DB_USE_ENVIRON_ROOT) && getuid() == 0)) {
#else
        if (LF_ISSET(DB_USE_ENVIRON)) {
#endif
                if ((p = getenv("DB_HOME")) == NULL)
                        p = db_home;
                else if (p[0] == '\0') {
                        __db_err(dbenv,
                            "illegal DB_HOME environment variable");
                        return (EINVAL);
                }
        }

        if (p == NULL)
                return (0);

        return (__os_strdup(p, &dbenv->db_home));
}

/*
 * __db_parse --
 *      Parse a single NAME VALUE pair.
 */
static int
__db_parse(dbenv, s)
        DB_ENV *dbenv;
        char *s;
{
        int ret;
        char *local_s, *name, *value, **p, *tp;

        /*
         * We need to strdup the argument in case the caller passed us
         * static data.
         */
        if ((ret = __os_strdup(s, &local_s)) != 0)
                return (ret);

        /*
         * Name/value pairs are parsed as two white-space separated strings.
         * Leading and trailing white-space is trimmed from the value, but
         * it may contain embedded white-space.  Note: we use the isspace(3)
         * macro because it's more portable, but that means that you can use
         * characters like form-feed to separate the strings.
         */
        name = local_s;
        for (tp = name; *tp != '\0' && !isspace(*tp); ++tp)
                ;
        if (*tp == '\0' || tp == name)
                goto illegal;
        *tp = '\0';
        for (++tp; isspace(*tp); ++tp)
                ;
        if (*tp == '\0')
                goto illegal;
        value = tp;
        for (++tp; *tp != '\0'; ++tp)
                ;
        for (--tp; isspace(*tp); --tp)
                ;
        if (tp == value) {
illegal:        ret = EINVAL;
                __db_err(dbenv, "illegal name-value pair: %s", s);
                goto err;
        }
        *++tp = '\0';

#define DATA_INIT_CNT   20                      /* Start with 20 data slots. */
        if (!strcmp(name, "DB_DATA_DIR")) {
                if (dbenv->db_data_dir == NULL) {
                        if ((ret = __os_calloc(DATA_INIT_CNT,
                            sizeof(char **), &dbenv->db_data_dir)) != 0)
                                goto err;
                        dbenv->data_cnt = DATA_INIT_CNT;
                } else if (dbenv->data_next == dbenv->data_cnt - 1) {
                        dbenv->data_cnt *= 2;
                        if ((ret = __os_realloc(&dbenv->db_data_dir,
                            dbenv->data_cnt * sizeof(char **))) != 0)
                                goto err;
                }
                p = &dbenv->db_data_dir[dbenv->data_next++];
        } else if (!strcmp(name, "DB_LOG_DIR")) {
                if (dbenv->db_log_dir != NULL)
                        __os_freestr(dbenv->db_log_dir);
                p = &dbenv->db_log_dir;
        } else if (!strcmp(name, "DB_TMP_DIR")) {
                if (dbenv->db_tmp_dir != NULL)
                        __os_freestr(dbenv->db_tmp_dir);
                p = &dbenv->db_tmp_dir;
        } else
                goto err;

        ret = __os_strdup(value, p);

err:    __os_freestr(local_s);
        return (ret);
}

/*
 * __db_tmp_open --
 *      Create a temporary file.
 */
static int
__db_tmp_open(dbenv, flags, path, fdp)
        DB_ENV *dbenv;
        u_int32_t flags;
        char *path;
        int *fdp;
{
        u_long pid;
        int mode, isdir, ret;
        const char *p;
        char *trv;

        /*
         * Check the target directory; if you have six X's and it doesn't
         * exist, this runs for a *very* long time.
         */
        if ((ret = __os_exists(path, &isdir)) != 0) {
                __db_err(dbenv, "%s: %s", path, strerror(ret));
                return (ret);
        }
        if (!isdir) {
                __db_err(dbenv, "%s: %s", path, strerror(EINVAL));
                return (EINVAL);
        }

        /* Build the path. */
        for (trv = path; *trv != '\0'; ++trv)
                ;
        *trv = PATH_SEPARATOR[0];
        for (p = DB_TRAIL; (*++trv = *p) != '\0'; ++p)
                ;

        /*
         * Replace the X's with the process ID.  Pid should be a pid_t,
         * but we use unsigned long for portability.
         */
        for (pid = getpid(); *--trv == 'X'; pid /= 10)
                switch (pid % 10) {
                case 0: *trv = '0'; break;
                case 1: *trv = '1'; break;
                case 2: *trv = '2'; break;
                case 3: *trv = '3'; break;
                case 4: *trv = '4'; break;
                case 5: *trv = '5'; break;
                case 6: *trv = '6'; break;
                case 7: *trv = '7'; break;
                case 8: *trv = '8'; break;
                case 9: *trv = '9'; break;
                }
        ++trv;

        /* Set up open flags and mode. */
        LF_SET(DB_CREATE | DB_EXCL);
        mode = __db_omode("rw----");

        /* Loop, trying to open a file. */
        for (;;) {
                if ((ret = __db_open(path, flags, flags, mode, fdp)) == 0)
                        return (0);

                /*
                 * XXX:
                 * If we don't get an EEXIST error, then there's something
                 * seriously wrong.  Unfortunately, if the implementation
                 * doesn't return EEXIST for O_CREAT and O_EXCL regardless
                 * of other possible errors, we've lost.
                 */
                if (ret != EEXIST) {
                        __db_err(dbenv,
                            "tmp_open: %s: %s", path, strerror(ret));
                        return (ret);
                }

                /*
                 * Tricky little algorithm for backward compatibility.
                 * Assumes the ASCII ordering of lower-case characters.
                 */
                for (;;) {
                        if (*trv == '\0')
                                return (EINVAL);
                        if (*trv == 'z')
                                *trv++ = 'a';
                        else {
                                if (isdigit(*trv))
                                        *trv = 'a';
                                else
                                        ++*trv;
                                break;
                        }
                }
        }
        /* NOTREACHED */
}