Now for the major refactoring. Introduce mod_isapi.h, as we have had

  untold problems with compatibility between different Visual Studio and
  PlatformSDK users [based on their generation of the MS ISAPI header.]
  This header is coded from scratch in native APR types.

  Replace the apr_array_t with an apr_hash_t, mutex protected, to allow us
  to preload and late-load isapi modules.  This closes a significant bug
  with trafficed sites using uncached isapi modules, where one would be
  closing the module just as another request is opening it [as if for the
  first time.]  This would cause some ISAPI modules to crash.  Now that
  we load modules for the lifetime of the server, a simple graceful restart
  is all that's required to unload all the non-precached modules.

  Crack out all FAKE_ASYNC code while we complete it.  Total support for
  the Completion Context callback and end-of-request termination is required
  before we can toggle this on.

  My next commit; complete fake async support.  But this was all I'd had
  in me for one night.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@95077 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 280 insertions, 0 deletions

diff --git a/modules/arch/win32/mod_isapi.h b/modules/arch/win32/mod_isapi.h
new file mode 100644
index 0000000000..3a4ffd951b
--- /dev/null
+++ b/modules/arch/win32/mod_isapi.h
@@ -0,0 +1,280 @@
+/* ====================================================================
+ * The Apache Software License, Version 1.1
+ *
+ * Copyright (c) 2000-2002 The Apache Software Foundation.  All rights
+ * reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Apache Software Foundation (http://www.apache.org/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Apache" and "Apache Software Foundation" must
+ *    not be used to endorse or promote products derived from this
+ *    software without prior written permission. For written
+ *    permission, please contact apache@apache.org.
+ *
+ * 5. Products derived from this software may not be called "Apache",
+ *    nor may "Apache" appear in their name, without prior written
+ *    permission of the Apache Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This software consists of voluntary contributions made by many
+ * individuals on behalf of the Apache Software Foundation.  For more
+ * information on the Apache Software Foundation, please see
+ * <http://www.apache.org/>.
+ *
+ * Portions of this software are based upon public domain software
+ * originally written at the National Center for Supercomputing Applications,
+ * University of Illinois, Urbana-Champaign.
+ */
+
+#ifndef MOD_ISAPI_H
+#define MOD_ISAPI_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* The Version Information storage passed to a module on startup
+ * via the GetExtensionVersion() entry point.
+ */
+typedef struct HSE_VERSION_INFO {
+    apr_uint32_t dwExtensionVersion;
+    char         lpszExtensionDesc[256];
+} HSE_VERSION_INFO;
+
+/* The startup entry point that must be exported by every ISAPI handler
+ */
+int APR_THREAD_FUNC GetExtensionVersion(HSE_VERSION_INFO *ver_info);
+typedef (APR_THREAD_FUNC *PFN_GETEXTENSIONVERSION)(HSE_VERSION_INFO *ver_info);
+
+/* Our internal 'HCONN' representation, always opaque to the user.
+ */
+typedef struct isapi_cid isapi_cid, *HCONN;
+
+/* Prototypes of the essential functions exposed by mod_isapi 
+ * for the module to communicate with Apache.
+ */
+typedef int (APR_THREAD_FUNC 
+                *PFN_GETSERVERVARIABLE)(HCONN         cid,
+                                        char         *variable_name,
+                                        void         *buf_data,
+                                        apr_uint32_t *buf_size);
+typedef int (APR_THREAD_FUNC 
+                *PFN_WRITECLIENT)(HCONN         cid, 
+                                  void         *buf_data,
+                                  apr_uint32_t *buf_size,
+                                  apr_uint32_t  flags);
+typedef int (APR_THREAD_FUNC 
+                *PFN_READCLIENT)(HCONN         cid, 
+                                 void         *buf_data,
+                                 apr_uint32_t *buf_size);
+typedef int (APR_THREAD_FUNC 
+                *PFN_SERVERSUPPORTFUNCTION)(HCONN         cid,
+                                            apr_uint32_t  HSE_code,
+                                            void         *buf_data,
+                                            apr_uint32_t *buf_size,
+                                            apr_uint32_t *flags);
+
+/* The ecb structure is passed on each invocation of the module
+ */
+typedef struct EXTENSION_CONTROL_BLOCK {
+    apr_uint32_t   cbSize;
+    apr_uint32_t   dwVersion;
+    HCONN          ConnID;
+    apr_uint32_t   dwHttpStatusCode;
+    char           lpszLogData[80];
+    char          *lpszMethod;
+    char          *lpszQueryString;
+    char          *lpszPathInfo;
+    char          *lpszPathTranslated;
+    apr_uint32_t   cbTotalBytes;
+    apr_uint32_t   cbAvailable;
+    unsigned char *lpbData;
+    char          *lpszContentType;
+
+    PFN_GETSERVERVARIABLE     GetServerVariable;
+    PFN_WRITECLIENT           WriteClient;
+    PFN_READCLIENT            ReadClient;
+    PFN_SERVERSUPPORTFUNCTION ServerSupportFunction;
+} EXTENSION_CONTROL_BLOCK;
+
+/* Status/Headers structure to pass to HSE_SEND_HEADER_EX, 
+ * an MS extension to ServerSupportFunction
+ */
+typedef struct HSE_SEND_HEADER_EX_INFO {
+    const char * pszStatus; /* HTTP status text, such as "200 OK" */
+    const char * pszHeader; /* HTTP header lines text, such as
+                             *   "Content-type: text/plain\r\n"
+                             *   "Content-Language: en\r\n" 
+                             * Note that (in spite of cchFoo lengths below)
+                             * NULL characters will interfere in headers.
+                             */
+    apr_uint32_t cchStatus; /* length of pszStatus text */
+    apr_uint32_t cchHeader; /* length of pszHeader text */
+    int          fKeepConn; /* Ignored: used to set keep-alive status,
+                             * but Apache follows the client's negotiated
+                             * HTTP contract to decide.
+                             */
+} HSE_SEND_HEADER_EX_INFO;
+
+/* Our only 'supported' MS extended flag bit for TransmitFile,
+ * HSE_IO_SEND_HEADERS indicates that Status+Headers are present
+ * in the pszStatusCode member of the HSE_TF_INFO structure.
+ */
+#define HSE_IO_SEND_HEADERS 8
+
+/* The remaining flags are MS extended flag bits that bear little
+ * relation to Apache; the rules that the Apache server obeys follow
+ * its own design and HTTP protocol filter rules.
+ *
+ * We do not support async, however, we fake it.  If HSE_IO_SYNC is 
+ * not passed, and a completion context was defined, we will invoke the
+ * completion function immediately following the transfer, and then
+ * return to the caller.  If HSE_IO_SYNC is passed, there is no call
+ * neccessary to the completion context.
+ */
+#define HSE_IO_SYNC  1
+#define HSE_IO_ASYNC 2
+#define HSE_IO_DISCONNECT_AFTER_SEND 4
+#define HSE_IO_NODELAY 4096
+
+/* The Completion function prototype.  This callback may be fixed with 
+ * the HSE_REQ_IO_COMPLETION ServerSupportFunction call, or overriden
+ * for the HSE_REQ_TRANSMIT_FILE call.
+ */
+typedef void (APR_THREAD_FUNC *PFN_HSE_IO_COMPLETION)
+                                  (EXTENSION_CONTROL_BLOCK *ecb,
+                                   void                    *ctxt,
+                                   apr_uint32_t             cbIO,
+                                   apr_uint32_t             dwError);
+
+/* TransmitFile structure to pass to HSE_REQ_TRANSMIT_FILE, an MS extension
+ */
+typedef struct HSE_TF_INFO {
+    PFN_HSE_IO_COMPLETION pfnHseIO;      /* Overrides the default setting of
+                                          * HSE_REQ_IO_COMPLETION if not NULL
+                                          */
+    void                 *pContext;
+    apr_os_file_t         hFile;         /* HANDLE/fd to transmit */
+    const char           *pszStatusCode; /* Ignored if HSE_IO_SEND_HEADERS is 
+                                          * not set.  Includes HTTP status text
+                                          * plus header text lines, such as
+                                          *   "200 OK\r\n"
+                                          *   "Content-type: text/plain\r\n"
+                                          */
+    apr_uint32_t          BytesToWrite;  /* 0 is write-all */
+    apr_uint32_t          Offset;        /* File Offset */
+    void                 *pHead;         /* Prefix with *pHead body text */
+    apr_uint32_t          HeadLength;    /* Length of *pHead body text */
+    void                 *pTail;         /* Prefix with *pTail body text */
+    apr_uint32_t          TailLength;    /* Length of *pTail body text */
+    apr_uint32_t          dwFlags;       /* bit flags described above */
+} HSE_TF_INFO;
+
+typedef struct HSE_URL_MAPEX_INFO {
+    char         lpszPath[MAX_PATH];
+    apr_uint32_t dwFlags;
+    apr_uint32_t cchMatchingPath;
+    apr_uint32_t cchMatchingURL;
+    apr_uint32_t dwReserved1;
+    apr_uint32_t dwReserved2;
+} HSE_URL_MAPEX_INFO;
+
+/* Original ISAPI ServerSupportFunction() HSE_code methods */
+#define HSE_REQ_SEND_URL_REDIRECT_RESP   1
+#define HSE_REQ_SEND_URL                 2
+#define HSE_REQ_SEND_RESPONSE_HEADER     3
+#define HSE_REQ_DONE_WITH_SESSION        4
+    
+/* MS Extented methods to ISAPI ServerSupportFunction() HSE_code */
+#define HSE_REQ_MAP_URL_TO_PATH          1001 /* Emulated */
+#define HSE_REQ_GET_SSPI_INFO            1002 /* Not Supported */
+#define HSE_APPEND_LOG_PARAMETER         1003 /* Supported */
+#define HSE_REQ_IO_COMPLETION            1005 /* Emulated */
+#define HSE_REQ_TRANSMIT_FILE            1006 /* Async Emulated */
+#define HSE_REQ_REFRESH_ISAPI_ACL        1007 /* Not Supported */
+#define HSE_REQ_IS_KEEP_CONN             1008 /* Supported */
+#define HSE_REQ_ASYNC_READ_CLIENT        1010 /* Emulated */
+/*   Added with ISAPI 4.0 */
+#define HSE_REQ_GET_IMPERSONATION_TOKEN  1011 /* Not Supported */
+#define HSE_REQ_MAP_URL_TO_PATH_EX       1012 /* Emulated */
+#define HSE_REQ_ABORTIVE_CLOSE           1014 /* Ignored */
+/*   Added after ISAPI 4.0 in IIS 5.0 */
+#define HSE_REQ_GET_CERT_INFO_EX         1015 /* Not Supported */
+#define HSE_REQ_SEND_RESPONSE_HEADER_EX  1016 /* Supported (no nulls!) */
+#define HSE_REQ_CLOSE_CONNECTION         1017 /* Ignored */
+#define HSE_REQ_IS_CONNECTED             1018 /* Supported */
+#define HSE_REQ_EXTENSION_TRIGGER        1020 /* Not Supported */
+
+/* The request entry point that must be exported by every ISAPI handler 
+ */
+apr_uint32_t APR_THREAD_FUNC HttpExtensionProc(EXTENSION_CONTROL_BLOCK *ecb);
+typedef apr_uint32_t (APR_THREAD_FUNC 
+                        *PFN_HTTPEXTENSIONPROC)(EXTENSION_CONTROL_BLOCK *ecb);
+
+/* Allowable return values from HttpExtensionProc (apparently 0 is also 
+ * accepted by MS IIS, and we will respect it as Success.)
+ * If the HttpExtensionProc returns HSE_STATUS_PENDING, we will create
+ * a wait mutex and lock on it, until HSE_REQ_DONE_WITH_SESSION is called.
+ */
+#define HSE_STATUS_SUCCESS                1
+#define HSE_STATUS_SUCCESS_AND_KEEP_CONN  2 /* 1 vs 2 Ignored, we choose */
+#define HSE_STATUS_PENDING                3 /* Emulated (thread lock) */
+#define HSE_STATUS_ERROR                  4
+
+/* Valid flags passed with TerminateExtension()
+ */
+#define HSE_TERM_MUST_UNLOAD      1
+#define HSE_TERM_ADVISORY_UNLOAD  2
+
+/* The shutdown entry point óptionally exported by an ISAPI handler, passed
+ * HSE_TERM_MUST_UNLOAD or HSE_TERM_ADVISORY_UNLOAD.  The module may return 
+ * if passed HSE_TERM_ADVISORY_UNLOAD, and the module will remain loaded.
+ * If the module returns 1 to HSE_TERM_ADVISORY_UNLOAD it is immediately 
+ * unloaded.  If the module is passed HSE_TERM_MUST_UNLOAD, its return value 
+ * is ignored.
+ */
+int APR_THREAD_FUNC TerminateExtension(apr_uint32_t flags);
+typedef int (APR_THREAD_FUNC *PFN_TERMINATEEXTENSION)(apr_uint32_t flags);
+
+/* Module may return 0 if passed HSE_TERM_ADVISORY_UNLOAD, and the module
+ * will remain loaded, or 1 if it consents to being unloaded. If the module
+ * is passed HSE_TERM_MUST_UNLOAD, it's return value is ignored.
+ */
+#define HSE_TERM_MUST_UNLOAD      1
+#define HSE_TERM_ADVISORY_UNLOAD  2
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif	/* !MOD_ISAPI_H */