Fix db_get_value after mysql->mysqli upgrade

[wfpl.git] / db.php

diff --git a/db.php b/db.php
index 5ac36a3..428c1bf 100644 (file)
--- a/db.php
+++ b/db.php
@@ -111,6 +111,7 @@ function db_send_query($sql) {
 #
 # %%  put a % in the output
 # %i  put an integer in the output (strips non-numeric digits, and puts in 0 if blank)
+# %I  a list of integers (as %i) separated by commas
 # %f  put a floating point value in the output (strips non-numeric digits, puts in 0.0 if not valid)
 # %"  output double quotes, surrounding the variable which is encoded to be in there.
 # %s  output encoded to be in double quotes, but don't output the quotes
@@ -147,9 +148,18 @@ function _db_printf($str, $args) {
                } elseif($chr == 's') {
                        $out .= db_enc_sql(array_shift($args));
                } elseif($chr == 'i') {
-                       $int = format_int(array_shift($args));
-                       if($int == '') $int = '0';
-                       $out .= $int;
+                       $out .= format_int_0(array_shift($args));
+               } elseif($chr == 'I') {
+                       $arg = array_shift($args);
+                       $first = true;
+                       foreach ($arg as $int) {
+                               if ($first) {
+                                       $first = false;
+                               } else {
+                                       $out .= ',';
+                               }
+                               $out .= format_int_0($int);
+                       }
                } elseif($chr == 'f') {
                        $arg = array_shift($args);
                        if(is_numeric($arg)) {
@@ -266,7 +276,7 @@ function db_get_value($table, $column, $where = '') {
        $result = db_send_get($table, $column, $where, $args);
 
        $value = mysqli_fetch_row($result);
-       if($value !== false) {
+       if($value !== NULL) {
                $value = $value[0];
        }
 
@@ -456,10 +466,22 @@ function db_reposition_respace($table, $field, $where = '') {
                return;
        }
        $inc = floor(DB_ORD_MAX / ($c + 1));
-       $cur = $inc;
-       foreach($ids as $id) {
-               db_update($table, $field, $cur, 'where id=%i', $id);
-               $cur += $inc;
+       $ord = $inc;
+       $count = count($ids);
+       for ($i = 0; $i < $count; $i += 1000) {
+               $values = [];
+               $j_max = min($count, $i + 1000);
+               for ($j = $i; $j < $j_max; ++$j) {
+                       $id = $ids[$j];
+                       $values[] = "($id,$ord)";
+                       $ord += $inc;
+               }
+               $sql =
+                       "insert into $table (id,$field) values "
+                       . implode(',', $values)
+                       . " on duplicate key update $field=VALUES($field)"
+               ;
+               db_send_query($sql);
        }
 }
 
@@ -535,3 +557,73 @@ function db_reposition($table, $row_id, $new_pos, $field = 'ord', $pretty = 'sam
                return $prev_ord + round(($next_ord - $prev_ord) / 2);
        }
 }
+
+# Call this to upgrade your database (using upgrade functions you define.)
+#
+# You can call this from config.php right after db_connect() to make sure the
+# database is up to date.
+#
+# When you want to update your schema, define a new function named
+# db_upgrade_to_X() where X is the next integer (start at 1).
+#
+# If there are any page views while your upgrade function is running, they will
+# stall until the upgrade function completes. This is often better than running
+# while the databse is in a transitional state, and is way way better than
+# running the upgrade function multiple times concurrently.
+#
+# Efficiency: this function is designed to be lean enough that you'd run it on
+# every page load, so you never forget to upgrade your schema after uploading
+# code changes. If your schema is up to date, this will only execute one
+# database query, and that query loads the persistent data store (used by
+# persistent_get()), so if you use that, you'll need that query to happen
+# anyway (giving this function a zero-query overhead).
+
+function db_upgrade() {
+       if (isset($GLOBALS['wfpl_persistent'])) {
+               $version = persistent_get('wfpl_db_version');
+       } else {
+               # custom version of persistent_init() that creates the table if needed
+               # instead of dying
+               $GLOBALS['wfpl_persistent'] = array();
+               _db_connection_needed();
+               $result = mysqli_query($GLOBALS['wfpl_db_handle'], 'select k,v from wfpl_persistent');
+               if ($result) {
+                       while($row = mysqli_fetch_assoc($result)) {
+                               $GLOBALS['wfpl_persistent'][$row['k']] = json_decode($row['v'], true);
+                       } unset($row);
+                       if (isset($GLOBALS['wfpl_persistent']['wfpl_db_version'])) {
+                               $version = $GLOBALS['wfpl_persistent']['wfpl_db_version'];
+                       } else {
+                               $version = -1;
+                       }
+               } else {
+                       db_send_query('create table if not exists wfpl_persistent (k varchar(30) binary not null default "", v mediumblob, primary key (k)) CHARSET=utf8;');
+                       $version = -1;
+               }
+       }
+
+       if ($version === -1) {
+               db_send_query('create table if not exists wfpl_mutexes (id int unique auto_increment, name varchar(255) binary, expires int(11)) CHARSET=utf8;');
+               $version = 0;
+               # don't save version now in case another thread is doing this too
+       }
+       $next = $version + 1;
+       if (function_exists("db_upgrade_to_$next")) {
+               require_once(__DIR__.'/'.'persistent.php');
+               require_once(__DIR__.'/'.'mutex.php');
+               mutex_lock('wfpl_db_upgrade', 20);
+               # check version again, in case another thread upgraded the database
+               # while we waited for a lock just now
+               persistent_invalidate_cache();
+               $version = persistent_get('wfpl_db_version');
+               if ($version === null) {
+                       $version = 0;
+               }
+
+               for ($next = $version + 1; function_exists("db_upgrade_to_$next"); ++$next) {
+                       call_user_func("db_upgrade_to_$next");
+                       persistent_set('wfpl_db_version', $next);
+               }
+               mutex_unlock('wfpl_db_upgrade');
+       }
+}