Function create_temp_table

lua/sp.c:1157–1234

** Lua stack: ** 1: Lua str (tmptbl name) ** 2: Lua tbl (tmptbl schema) */

** 2: Lua tbl (tmptbl schema)
*/
static int create_temp_table(Lua lua, pthread_mutex_t **lk, const char **name)
{
    int rc = -1;
    strbuf *sql = NULL;
    SP sp = getsp(lua);
    char n1[MAXTABLELEN], n2[MAXTABLELEN];
    *name = lua_tostring(lua, 1);
    if (two_part_tbl_name(*name, n1, n2) != 0) {
        luabb_error(lua, sp, "bad table name:%s", *name);
        goto out;
    }
    if (strcasecmp(n1, "") != 0 && strcasecmp(n1, "temp") != 0) {
        luabb_error(lua, sp, "bad table name:%s", *name);
        goto out;
    }
    sql = strbuf_new();
    strbuf_appendf(sql, "CREATE TEMP TABLE \"%s\" (", n2);
    size_t num = lua_objlen(lua, 2);
    const char *comma = "";
    for (size_t i = 1; i <= num; ++i) {
        lua_rawgeti(lua, 2, i);
        if (!lua_istable(lua, -1)) {
            luabb_error(lua, sp, "bad argument (columns) to 'table'");
            goto out;
        }
        if (lua_objlen(lua, -1) != 2) { // need {"name", "type"}
            luabb_error(lua, sp, "bad argument (columns) to 'table'");
            goto out;
        }
        lua_rawgeti(lua, -1, 1);
        lua_rawgeti(lua, -2, 2);
        char *quoted_col = sqlite3_mprintf("\"%w\"", lua_tostring(lua, -2));
        strbuf_appendf(sql, "%s%s %s", comma, quoted_col,
                       lua_tostring(lua, -1));
        sqlite3_free(quoted_col);
        lua_pop(lua, 3);
        comma = ", ";
    }
    strbuf_append(sql, ")");

    // Following can throw exception which may leak strbuf.
    // Copy DDL string onto stack instead.
    int len = strbuf_len(sql) + 1;
    char *ddl = alloca(len);
    memcpy(ddl, strbuf_buf(sql), len);
    strbuf_free(sql);
    sql = NULL;
    sqlite3_stmt *stmt;
    if ((rc = lua_prepare_sql_with_temp_ddl(sp, ddl, &stmt)) != 0) {
        goto out;
    }

    *lk = malloc(sizeof(pthread_mutex_t));
    Pthread_mutex_init(*lk, NULL);
    comdb2_set_tmptbl_lk(*lk);
    lua_begin_step(sp->clnt, sp, stmt);
    while ((rc = sqlite3_maybe_step(sp->clnt, stmt)) == SQLITE_ROW) {
        lua_another_step(sp->clnt, stmt, rc);