+ return $plugin_version;
+
+}
+
+/**
+ * Check a plugin's version.
+ *
+ * Returns TRUE if the given plugin is installed,
+ * activated and is at minimum version $a.$b.$c.
+ * If any one of those conditions fails, FALSE
+ * will be returned (careful of plugins that are
+ * sufficiently versioned but are not activated).
+ *
+ * By overriding the default value of $force_inclusion,
+ * this function will attempt to grab versioning
+ * information from the given plugin even if it
+ * is not activated (the plugin still has to be
+ * unpackaged and set in place in the plugins
+ * directory). Use with care - some plugins
+ * might break SquirrelMail when this is used.
+ *
+ * Note that this function assumes plugin
+ * versioning is consistently applied in the same
+ * fashion that SquirrelMail versions are, with the
+ * exception that an applicable SquirrelMail
+ * version may be appended to the version number
+ * (which will be ignored herein). That is, plugin
+ * version number schemes are expected in the following
+ * format: 1.2.3, or 1.2.3-1.4.0.
+ *
+ * Any characters after the third number indicating
+ * things such as beta or release candidate versions
+ * are discarded, so formats such as the following
+ * will also work, although extra information about
+ * beta versions can possibly confuse the desired results
+ * of the version check: 1.2.3-beta4, 1.2.3.RC2, and so forth.
+ *
+ * @since 1.5.2
+ *
+ * @param string plugin_name Name of the plugin to
+ * check; must precisely
+ * match the plugin
+ * directory name
+ * @param int a Major version number
+ * @param int b Minor version number
+ * @param int c Release number
+ * @param bool force_inclusion Try to get version info
+ * for plugins not activated?
+ * (default FALSE)
+ *
+ * @return bool
+ *
+ */
+function check_plugin_version($plugin_name,
+ $a = 0, $b = 0, $c = 0,
+ $force_inclusion = FALSE)
+{
+
+ $plugin_version = get_plugin_version($plugin_name, $force_inclusion, TRUE);
+ if (!$plugin_version) return FALSE;
+
+
+ // split the version string into sections delimited by
+ // decimal points, and make sure we have three sections
+ //
+ $plugin_version = explode('.', $plugin_version);
+ if (!isset($plugin_version[0])) $plugin_version[0] = 0;
+ if (!isset($plugin_version[1])) $plugin_version[1] = 0;
+ if (!isset($plugin_version[2])) $plugin_version[2] = 0;
+// sm_print_r($plugin_version);
+
+
+ // now test the version number
+ //
+ if ($plugin_version[0] < $a ||
+ ($plugin_version[0] == $a && $plugin_version[1] < $b) ||
+ ($plugin_version[0] == $a && $plugin_version[1] == $b && $plugin_version[2] < $c))
+ return FALSE;
+
+
+ return TRUE;
+
+}
+
+/**
+ * Get a certain plugin requirement.
+ *
+ * Attempts to find the given plugin requirement value
+ * in the given plugin's informational array, and returns
+ * it or NULL if it was not found.
+ *
+ * Some plugins have different values for the same
+ * requirement depending on the SquirrelMail version,
+ * and this function is smart enough to take that into
+ * account.
+ *
+ * By default, the desired plugin must be currently
+ * activated, and if it is not, this function will
+ * return NULL. By overriding the default value
+ * of $force_inclusion, this function will attempt
+ * to grab requirement information from the given
+ * plugin even if it is not activated (plugin still
+ * has to be unpackaged and set in place in the
+ * plugins directory). Use with care - some plugins
+ * might break SquirrelMail when this is used.
+ *
+ * @since 1.5.2
+ *
+ * @param string $plugin_name Name of the plugin to
+ * check; must precisely
+ * match the plugin
+ * directory name
+ * @param string $requirement The desired requirement name
+ * @param boolean $ignore_incompatible When TRUE, version incompatibility
+ * information will NOT be returned
+ * if found; when FALSE, it will be
+ * (OPTIONAL; default TRUE)
+ * @param boolean $force_inclusion Try to get requirement info
+ * for plugins not activated?
+ * (OPTIONAL; default FALSE)
+ *
+ * @return mixed NULL is returned if the plugin could not be
+ * found or does not include the given requirement,
+ * the constant SQ_INCOMPATIBLE is returned if the
+ * given plugin is entirely incompatible with the
+ * current SquirrelMail version (unless
+ * $ignore_incompatible is TRUE), otherwise the
+ * value of the requirement is returned, whatever
+ * that may be (varies per requirement type).
+ *
+ */
+function get_plugin_requirement($plugin_name, $requirement,
+ $ignore_incompatible = TRUE,
+ $force_inclusion = FALSE)
+{
+
+ $info_function = $plugin_name . '_info';
+ $plugin_info = array();
+ $requirement_value = NULL;
+
+
+ // first attempt to find the plugin info function, wherein
+ // the plugin requirements should be available
+ //
+ if (function_exists($info_function))
+ $plugin_info = $info_function();
+ else if ($force_inclusion
+ && file_exists(SM_PATH . 'plugins/' . $plugin_name . '/setup.php'))
+ {
+
+ /* --- Old code, keeping just in case... problem with it is, for example,
+ if it is used, but later we are checking if the same plugin is
+ activated (because it SHOULD be), this code having run will possibly
+ create a false positive.
+ include_once(SM_PATH . 'plugins/' . $plugin_name . '/setup.php');
+ if (function_exists($info_function))
+ $plugin_info = $info_function();
+ --- */
+
+ // so what we need to do is process this plugin without
+ // it polluting our environment
+ //
+ // we *could* just use the above code, which is more of a
+ // sure thing than a regular expression, and then test
+ // the contents of the $plugins array to see if this plugin
+ // is actually activated, and that might be good enough, but
+ // for now, we'll use the following approach, because of two
+ // concerns: other plugins and other templates might force
+ // the inclusion of a plugin (which SHOULD also add it to
+ // the $plugins array, but am not 100% sure at this time (FIXME)),
+ // and because the regexp below should work just fine with
+ // any resonably formatted plugin setup file.
+ //
+ // read the target plugin's setup.php file into a string,
+ // then use a regular expression to try to find the needed
+ // requirement information...
+ // this of course can break if plugin authors do funny things
+ // with their file formatting
+ //
+ $setup_file = '';
+ $file_contents = file(SM_PATH . 'plugins/' . $plugin_name . '/setup.php');
+ foreach ($file_contents as $line)
+ $setup_file .= $line;
+
+
+ // this regexp grabs the full plugin info array from a standard
+ // <plugin>_info() function... determining the end of the info
+ // array can fail, but if authors end the array with ");\n"
+ // (without quotes), then it should work well, especially because
+ // newlines shouldn't be found inside the array after any ");"
+ // (without quotes)
+ //
+ if (preg_match('/function\s+.*?' . $plugin_name . '_info.*?\(.*?\).*?\{.*?(array.+?\)\s*;)\s*' . "\n" . '/is', $setup_file, $matches))
+ eval('$plugin_info = ' . $matches[1]);
+
+ }
+
+
+ // attempt to get the requirement from the "global" scope
+ // of the plugin information array
+ //
+ if (isset($plugin_info[$requirement])
+ && !is_null($plugin_info[$requirement]))
+ $requirement_value = $plugin_info[$requirement];
+
+
+ // now, if there is a series of per-version requirements,
+ // check there too
+ //
+ if (!empty($plugin_info['per_version_requirements'])
+ && is_array($plugin_info['per_version_requirements']))
+ {
+
+ // iterate through requirements, where keys are version
+ // numbers -- tricky part is knowing the difference between
+ // more than one version for which the current SM installation
+ // passes the check_sm_version() test... we want the highest one
+ //
+ $requirement_value_override = NULL;
+ $highest_version_array = array();
+ foreach ($plugin_info['per_version_requirements'] as $version => $requirement_overrides)
+ {
+
+ $version_array = explode('.', $version);
+ if (sizeof($version_array) != 3) continue;
+
+ $a = $version_array[0];
+ $b = $version_array[1];
+ $c = $version_array[2];
+
+ // complicated way to say we are interested in these overrides
+ // if the version is applicable to us and if the overrides include
+ // the requirement we are looking for, or if the plugin is not
+ // compatible with this version of SquirrelMail (unless we are
+ // told to ignore such)
+ //
+ if (check_sm_version($a, $b, $c)
+ && ((!$ignore_incompatible
+ && (!empty($requirement_overrides[SQ_INCOMPATIBLE])
+ || $requirement_overrides === SQ_INCOMPATIBLE))
+ || (is_array($requirement_overrides)
+ && isset($requirement_overrides[$requirement])
+ && !is_null($requirement_overrides[$requirement]))))
+ {
+
+ if (empty($highest_version_array)
+ || $highest_version_array[0] < $a
+ || ($highest_version_array[0] == $a
+ && $highest_version_array[1] < $b)
+ || ($highest_version_array[0] == $a
+ && $highest_version_array[1] == $b
+ && $highest_version_array[2] < $c))
+ {
+ $highest_version_array = $version_array;
+ if (!empty($requirement_overrides[SQ_INCOMPATIBLE])
+ || $requirement_overrides === SQ_INCOMPATIBLE)
+ $requirement_value_override = SQ_INCOMPATIBLE;
+ else
+ $requirement_value_override = $requirement_overrides[$requirement];
+ }
+
+ }
+
+ }
+
+ // now grab override if one is available
+ //
+ if (!is_null($requirement_value_override))
+ $requirement_value = $requirement_value_override;
+
+ }
+
+ return $requirement_value;
+
+}
+
+/**
+ * Get a plugin's other plugin dependencies.
+ *
+ * Determines and returns all the other plugins
+ * that a given plugin requires, as well as the
+ * minimum version numbers of the required plugins
+ * and whether or not they need to be activated.
+ *
+ * By default, the desired plugin must be currently
+ * activated, and if it is not, this function will
+ * return FALSE. By overriding the default value
+ * of $force_inclusion, this function will attempt
+ * to grab dependency information from the given
+ * plugin even if it is not activated (plugin still
+ * has to be unpackaged and set in place in the
+ * plugins directory). Use with care - some plugins
+ * might break SquirrelMail when this is used.
+ *
+ * By turning on the $do_parse argument (it is on by
+ * default), the version string for each required
+ * plugin will be parsed by SquirrelMail into a
+ * SquirrelMail-compatible version string (such as
+ * "1.2.3") if it is not already. See notes about
+ * version formatting under the get_plugin_version()
+ * function documentation.
+ *
+ * @since 1.5.2
+ *
+ * @param string plugin_name name of the plugin to
+ * check; must precisely
+ * match the plugin
+ * directory name
+ * @param bool force_inclusion try to get version info
+ * for plugins not activated?
+ * (default FALSE)
+ * @param bool do_parse return the version numbers
+ * for required plugins in
+ * SquirrelMail-compatible
+ * format (default FALSE)
+ *
+ * @return mixed Boolean FALSE is returned if the plugin
+ * could not be found or does not indicate
+ * whether it has other plugin dependencies,
+ * the constant SQ_INCOMPATIBLE is returned if
+ * the given plugin is entirely incompatible
+ * with the current SquirrelMail version,
+ * otherwise an array is returned where keys
+ * are the names of required plugin
+ * dependencies, and values are arrays again,
+ * where at least the following keys (and
+ * corresponding values) will be available:
+ * 'version' - value is the minimum version
+ * required for that plugin (the format of
+ * which might vary per the value of $do_parse
+ * as well as if the plugin requires a SquirrelMail
+ * core plugin, in which case it is "CORE" or
+ * "CORE:1.5.2" or similar, or, if the plugin is
+ * actually incompatible (not required) with this
+ * one, the constant SQ_INCOMPATIBLE will be found
+ * here), 'activate' - value is boolean: TRUE
+ * indicates that the plugin must also be activated,
+ * FALSE means that it only needs to be present,
+ * but does not need to be activated. Note that
+ * the return value might be an empty array,
+ * indicating that the plugin has no dependencies.
+ *
+ */
+function get_plugin_dependencies($plugin_name, $force_inclusion = FALSE,
+ $do_parse = TRUE)
+{
+
+ $plugin_dependencies = get_plugin_requirement($plugin_name,
+ 'required_plugins',
+ FALSE,
+ $force_inclusion);
+
+ // the plugin is simply incompatible, no need to continue here
+ //
+ if ($plugin_dependencies === SQ_INCOMPATIBLE)
+ return $plugin_dependencies;
+
+
+ // not an array of requirements? wrong format, just return FALSE
+ //
+ if (!is_array($plugin_dependencies))
+ return FALSE;
+
+
+ // make sure everything is in order...
+ //
+ if (!empty($plugin_dependencies))
+ {
+
+ $new_plugin_dependencies = array();
+ foreach ($plugin_dependencies as $plugin_name => $plugin_requirements)
+ {
+
+ // if $plugin_requirements isn't an array, this is old-style,
+ // where only the version number was given...
+ //
+ if (is_string($plugin_requirements))
+ $plugin_requirements = array('version' => $plugin_requirements,
+ 'activate' => FALSE);
+
+
+ // trap badly formatted requirements arrays that don't have
+ // needed info
+ //
+ if (!is_array($plugin_requirements)
+ || !isset($plugin_requirements['version']))
+ continue;
+ if (!isset($plugin_requirements['activate']))
+ $plugin_requirements['activate'] = FALSE;
+
+
+ // parse version into something we understand?
+ //
+ if ($do_parse && $plugin_requirements['version'] != SQ_INCOMPATIBLE)
+ {
+
+ // massage version number into something we understand
+ //
+ // the first regexp strips everything and anything that follows
+ // the first occurance of a non-digit (or non decimal point), so
+ // beware that putting letters in the middle of a version string
+ // will effectively truncate the version string right there (but
+ // this also just helps remove the SquirrelMail version part off
+ // of versions such as "1.2.3-1.4.4")
+ //
+ // the second regexp just strips out non-digits/non-decimal points
+ // (and might be redundant(?))
+ //
+ // the regexps are wrapped in a trim that makes sure the version
+ // does not start or end with a decimal point
+ //
+ if (strpos(strtoupper($plugin_requirements['version']), 'CORE') === 0)
+ {
+ if (strpos($plugin_requirements['version'], ':') === FALSE)
+ $plugin_requirements['version'] = 'CORE';
+ else
+ $plugin_requirements['version']
+ = 'CORE:' . trim(preg_replace(array('/[^0-9.]+.*$/', '/[^0-9.]/'),
+ '', substr($plugin_requirements['version'], strpos($plugin_requirements['version'], ':') + 1)),
+ '.');
+ }
+ else
+ $plugin_requirements['version']
+ = trim(preg_replace(array('/[^0-9.]+.*$/', '/[^0-9.]/'),
+ '', $plugin_requirements['version']),
+ '.');
+