Add <IfDirective> and <IfSection>:

* server/core.c
  (test_ifdirective_section, test_ifsection_section): New callbacks.
  (core_cmds): Define new directives.

* include/http_config.h, server/config.c (ap_exists_directive):
  New function.

* include/ap_mmn.h: Bump MMN minor for above.

* docs/manual/mod/core.xml: Add docs.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1786110 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/CHANGES b/CHANGES
index 0b083fbb4e3457311cfa872ebff4e30c37ac473e..22cf09ff49ee5d75fe830e8da4edeb8a1ef350a6 100644 (file)
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,8 @@
                                                          -*- coding: utf-8 -*-
 Changes with Apache 2.5.0
 
+  *) Add <IfDirective> and <IfSection> directives.  [Joe Orton]
+
   *) mod_http2: stream timeouts now change to vhost values once the request
      is parsed and processing starts. Initial values are taken from base
      server or SNI host as before. [Stefan Eissing]

diff --git a/docs/manual/mod/core.xml b/docs/manual/mod/core.xml
index c7f83b10af7dca85cfe71b2aef65c583811f834f..8213a83dafef8c52dcf9ef1391096f94f0a60c55 100644 (file)
--- a/docs/manual/mod/core.xml
+++ b/docs/manual/mod/core.xml
@@ -788,12 +788,12 @@ DefaultType None
 </contextlist>
 
 <usage>
-    <p>In its one parameter form, <directive>Define</directive> is equivalent
-    to passing the <code>-D</code> argument to <program>httpd</program>. It
-    can be used to toggle the use of
-    <directive module="core" type="section">IfDefine</directive> sections
-    without needing to alter <code>-D</code> arguments in any startup
-    scripts.</p>
+    <p>In its one parameter form, <directive>Define</directive> is
+    equivalent to passing the <code>-D</code> argument to
+    <program>httpd</program>. It can be used to toggle the use of
+    <directive module="core" type="section">IfDefine</directive>
+    sections without needing to alter <code>-D</code> arguments in any
+    startup scripts.</p>
 
     <p>In addition to that, if the second parameter is given, a config variable
     is set to this value. The variable can be used in the configuration using
@@ -2389,6 +2389,108 @@ presence or absence of a specific module</description>
 </usage>
 </directivesynopsis>
 
+<directivesynopsis type="section">
+<name>IfDirective</name>
+<description>Encloses directives that are processed conditional on the
+presence or absence of a specific directive</description>
+<syntax>&lt;IfDirective [!]<var>directive-name</var>&gt; ...
+    &lt;/IfDirective&gt;</syntax>
+<contextlist><context>server config</context><context>virtual host</context>
+<context>directory</context><context>.htaccess</context>
+</contextlist>
+<override>All</override>
+
+<usage>
+    <p>The <code>&lt;IfDirective <var>test</var>&gt;...&lt;/IfDirective&gt;</code>
+    section is used to mark directives that are conditional on the presence of
+    a specific directive. The directives within an <directive type="section"
+    >IfDirective</directive> section are only processed if the <var>test</var>
+    is true. If <var>test</var> is false, everything between the start and
+    end markers is ignored.</p>
+
+    <p>The <var>test</var> in the <directive type="section"
+    >IfDirective</directive> section can be one of two forms:</p>
+
+    <ul>
+      <li><var>directive-name</var></li>
+
+      <li>!<var>directive-name</var></li>
+    </ul>
+
+    <p>In the former case, the directives between the start and end
+    markers are only processed if a directive of the given name is
+    available at the time of processing.  The second format reverses the test,
+    and only processes the directives if the <var>directive-name</var> is
+    <strong>not</strong> defined.</p>
+
+    <note>This section should only be used if you need to have one
+    configuration file that works across multiple versions of
+    <program>httpd</program>, regardless of whether a particular
+    directive is available. In normal operation, directives need not
+    be placed in <directive type="section">IfDirective</directive>
+    sections.</note>
+</usage>
+<seealso><directive module="core" type="section">IfSection</directive></seealso>
+</directivesynopsis>
+
+<directivesynopsis type="section">
+<name>IfSection</name>
+<description>Encloses directives that are processed conditional on the
+presence or absence of a specific section directive</description>
+<syntax>&lt;IfSection [!]<var>section-name</var>&gt; ...
+    &lt;/IfSection&gt;</syntax>
+<contextlist><context>server config</context><context>virtual host</context>
+<context>directory</context><context>.htaccess</context>
+</contextlist>
+<override>All</override>
+
+<usage>
+    <p>The <code>&lt;IfSection
+    <var>test</var>&gt;...&lt;/IfSection&gt;</code> section is used
+    to mark directives that are conditional on the presence of a
+    specific section directive.  A section directive is any directive
+    such as <directive type="section">virtualhost</directive> which
+    encloses other directives, and has a directive name with a leading
+    "&lt;".  The sec
+
+    The directives within an <directive type="section"
+    >IfSection</directive> section are only processed if the <var>test</var>
+    is true. If <var>test</var> is false, everything between the start and
+    end markers is ignored.</p>
+
+    <p>The <var>section-name</var> specified must not include the
+    leading "&lt;".  The <var>test</var> in the <directive
+    type="section">IfSection</directive> section can be one of two
+    forms:</p>
+
+    <ul>
+      <li><var>section-name</var></li>
+      <li>!<var>section-name</var></li>
+    </ul>
+
+    <p>In the former case, the directives between the start and
+    end markers are only processed if a section directive of the given
+    name is available at the time of processing.  The second format
+    reverses the test, and only processes the directives if the
+    <var>section-name</var> is <strong>not</strong> defined.</p>
+
+    <p>For example:</p>
+
+    <highlight language="config">
+&lt;IfSection VirtualHost&gt;
+   ...
+&lt;/IfSection&gt;
+    </highlight>
+    
+    <note>This section should only be used if you need to have one
+    configuration file that works across multiple versions of <program>httpd</program>,
+    regardless of whether a particular section directive is
+    available. In normal operation, directives need not be placed in
+    <directive type="section">IfSection</directive> sections.</note>
+</usage>
+<seealso><directive module="core" type="section">IfDirective</directive></seealso>
+</directivesynopsis>
+
 <directivesynopsis>
 <name>Include</name>
 <description>Includes other configuration files from within

diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index 31c9cd7a8a070f74109b041d72df01e75d935b49..fa75033f3a878c1a554df6f64910320bf979c78b 100644 (file)
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -550,6 +550,7 @@
  *                         ap_get_http_token() and http_stricturi conf member.
  *                         Added ap_scan_vchar_obstext()
  * 20161018.2 (2.5.0-dev)  add ap_set_conn_count()
+ * 20161018.3 (2.5.0-dev)  add ap_exists_directive()
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */
@@ -557,7 +558,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20161018
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 2                 /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 3                 /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a

diff --git a/include/http_config.h b/include/http_config.h
index 2982a8d2e8e5b898006ea2f5d6712ce2bbf20ecf..582cb243b5a327ab29f1a166b1d539b86b8e9c7b 100644 (file)
--- a/include/http_config.h
+++ b/include/http_config.h
@@ -991,6 +991,14 @@ AP_DECLARE(const char *) ap_setup_prelinked_modules(process_rec *process);
  */
 AP_DECLARE(void) ap_show_directives(void);
 
+/**
+ * Returns non-zero if a configuration directive of the given name has
+ * been registered by a module at the time of calling.
+ * @param p Pool for temporary allocations
+ * @param name Directive name
+ */
+AP_DECLARE(int) ap_exists_directive(apr_pool_t *p, const char *name);
+
 /**
  * Show the preloaded module names.  Used for httpd -l.
  */

diff --git a/server/config.c b/server/config.c
index 8e591dfc7f715277ebc4ca543bae0ded41bc3499..5af0e2d2de4f4950a0ab8de3d1e466198ced87f3 100644 (file)
--- a/server/config.c
+++ b/server/config.c
@@ -2668,6 +2668,16 @@ AP_DECLARE(void) ap_show_modules(void)
         printf("  %s\n", ap_loaded_modules[n]->name);
 }
 
+AP_DECLARE(int) ap_exists_directive(apr_pool_t *p, const char *name)
+{
+    char *lname = apr_pstrdup(p, name);
+
+    ap_str_tolower(lname);
+    
+    return ap_config_hash &&
+        apr_hash_get(ap_config_hash, lname, APR_HASH_KEY_STRING) != NULL;
+}
+
 AP_DECLARE(void *) ap_retained_data_get(const char *key)
 {
     void *retained;

diff --git a/server/core.c b/server/core.c
index a6db948c7af90797ac46d3fcb64e1bcfb520cf6a..612f585020bb94520412e41bb6050ab290b07993 100644 (file)
--- a/server/core.c
+++ b/server/core.c
@@ -2838,6 +2838,17 @@ static int test_iffile_section(cmd_parms *cmd, const char *arg)
     return (apr_stat(&sb, relative, 0, cmd->pool) == APR_SUCCESS);
 }
 
+static int test_ifdirective_section(cmd_parms *cmd, const char *arg)
+{
+    return ap_exists_directive(cmd->temp_pool, arg);
+}
+
+static int test_ifsection_section(cmd_parms *cmd, const char *arg)
+{
+    const char *name = apr_pstrcat(cmd->temp_pool, "<", arg, NULL);
+    return ap_exists_directive(cmd->temp_pool, name);
+}
+
 /* httpd.conf commands... beginning with the <VirtualHost> business */
 
 static const char *virtualhost_section(cmd_parms *cmd, void *dummy,
@@ -4456,6 +4467,12 @@ AP_INIT_TAKE1("<IfDefine", start_cond_section, (void *)test_ifdefine_section,
 AP_INIT_TAKE1("<IfFile", start_cond_section, (void *)test_iffile_section,
               EXEC_ON_READ | OR_ALL,
   "Container for directives based on existence of files on disk"),
+AP_INIT_TAKE1("<IfDirective", start_cond_section, (void *)test_ifdirective_section,
+              EXEC_ON_READ | OR_ALL,
+  "Container for directives based on existence of named directive"),
+AP_INIT_TAKE1("<IfSection", start_cond_section, (void *)test_ifsection_section,
+              EXEC_ON_READ | OR_ALL,
+  "Container for directives based on existence of named section"),
 AP_INIT_RAW_ARGS("<DirectoryMatch", dirsection, (void*)1, RSRC_CONF,
   "Container for directives affecting resources located in the "
   "specified directories"),