Annotation of libwww/Library/src/HTAccess.html, revision 2.53
2.9 timbl 1: <HTML>
2: <HEAD>
2.45 frystyk 3: <TITLE>Access manager for libwww</TITLE>
2.19 timbl 4: <NEXTID N="z11">
2.9 timbl 5: </HEAD>
2.5 timbl 6: <BODY>
2.39 frystyk 7:
2.33 frystyk 8: <H1>Access Manager</H1>
2.39 frystyk 9:
2.41 frystyk 10: <PRE>
11: /*
2.50 frystyk 12: ** (c) COPYRIGHT MIT 1995.
2.41 frystyk 13: ** Please first read the full copyright statement in the file COPYRIGH.
14: */
15: </PRE>
16:
2.39 frystyk 17: This module keeps a list of valid protocol (naming scheme) specifiers
18: with associated access code. It allows documents to be loaded given
19: various combinations of parameters. New access protocols may be
20: registered at any time.<P>
21:
22: This module is implemented by <A HREF="HTAccess.c">HTAccess.c</A>, and
23: it is a part of the <A NAME="z10"
2.46 frystyk 24: HREF="http://www.w3.org/hypertext/WWW/Library/User/Guide/Guide.html">Library
2.39 frystyk 25: of Common Code</A>. <P>
26:
27: The module contains a lot of stuff but the main topics are:
28:
29: <UL>
2.41 frystyk 30: <LI><A HREF="#Library">Initializing and Terminating the Library</A>
2.52 frystyk 31: <LI><A HREF="#Addresses">Default Directories and URLs</A>
32: <LI><A HREF="#flags">Global Flags</A><P>
33:
34: <LI><A HREF="#z100">Management of the HTRequest Object</A>
35: <LI><A HREF="#Methods">Management of HTTP Methods (GET, PUT, etc.)</A> <P>
36: <LI><A HREF="#user">Local User preferences</A>
37:
38: <LI><A HREF="#ProtReg">Access Method Registration</H2></A> <P>
39:
2.39 frystyk 40: <LI><A HREF="#LoadDoc">Functions for loading a document</A>
41: <LI><A HREF="#ClientHelp">Help functions for clients to get started</A>
2.52 frystyk 42: <LI><A HREF="#PostDoc">Functions for posting a document</A> <P>
43:
44: <LI><A HREF="#Int">Internal Data Structures</A>
2.39 frystyk 45: </UL>
46:
2.33 frystyk 47:
48: <PRE>
49: #ifndef HTACCESS_H
1.1 timbl 50: #define HTACCESS_H
2.44 roeber 51:
2.52 frystyk 52: #include "<A HREF="HTList.html">HTList.h</A>"
53: #include "<A HREF="HTChunk.html">HTChunk.h</A>"
54: #include "<A HREF="HTAnchor.html">HTAnchor.h</A>"
55: #include "<A HREF="HTStream.html">HTStream.h</A>"
56: #include "<A HREF="HTAssoc.html">HTAssoc.h</A>"
57: </PRE>
58:
59: <A NAME="Library"><H2>Initializing and Terminating the Library</H2></A>
60:
61: <IMG SRC="http://www.w3.org/hypertext/WWW/Icons/32x32/warning.gif">
62: These two functions initiates memory and settings for the Library and
63: cleans up memory kept by the Library when about to exit the
64: application. It is highly recommended that they are used!
65:
66: <PRE>
67: extern BOOL HTLibInit NOPARAMS;
68: extern BOOL HTLibTerminate NOPARAMS;
69: </PRE>
70:
71: <A NAME="Addresses"><H2>Default WWW Addresses</H2></A>
72:
73: These control the home page selection. To mess with these for normal browses
74: is asking for user confusion.
75: <PRE>
76: #define LOGICAL_DEFAULT "WWW_HOME" /* Defined to be the home page */
77:
78: #ifndef PERSONAL_DEFAULT
79: #define PERSONAL_DEFAULT "WWW/default.html" /* in home directory */
80: #endif
81:
82: /* If the home page isn't found, use this file: */
83: #ifndef LAST_RESORT
84: #define LAST_RESORT "http://www.w3.org/"
85: #endif
86:
87: /* If one telnets to an access point it will look in this file for home page */
88: #ifndef REMOTE_POINTER
89: #define REMOTE_POINTER "/etc/www-remote.url" /* can't be file */
90: #endif
91:
92: /* and if that fails it will use this. */
93: #ifndef REMOTE_ADDRESS
94: #define REMOTE_ADDRESS "http://www.w3.org/" /* can't be file */
95: #endif
96:
97: /* Default log file name */
98: #ifndef DEFAULT_LOGFILE
99: #define DEFAULT_LOGFILE "www-log"
100: #endif
101:
102: #ifndef LOCAL_DEFAULT_FILE
103: #define LOCAL_DEFAULT_FILE "/usr/local/lib/WWW/default.html"
104: #endif
105:
106: /* This is the default cache directory: */
107: #ifndef HT_CACHE_ROOT
108: #define HT_CACHE_ROOT "/tmp"
109: #endif
110:
111: /* The default directory for "save locally" and "save and execute" files: */
112: #ifndef HT_TMP_ROOT
113: #define HT_TMP_ROOT "/tmp"
114: #endif
2.35 frystyk 115: </PRE>
1.1 timbl 116:
2.52 frystyk 117: <A NAME="flags"><H2>Global Flags</H2></A>
2.46 frystyk 118:
119: Flags and variables which may be set to control the Library
120:
2.52 frystyk 121: <H3>Maximum Number of Redirections</H3>
2.46 frystyk 122:
123: The maximum number of redirections is pr. default 10. This prevents
124: the library from going into an infinite loop which is kind of nice :-)
2.52 frystyk 125: It is normally not necessary to change the default value.
2.46 frystyk 126:
2.35 frystyk 127: <PRE>
2.46 frystyk 128: extern int HTMaxRedirections;
2.33 frystyk 129: </PRE>
1.1 timbl 130:
2.52 frystyk 131: <H3>Allow Accss to Local File System</H3>
132:
133: This flag can be used to deny an application to get access to the
134: local file system (through cache, file URLs etc.)
135:
136: <PRE>
137: extern BOOL HTSecure; /* Disable security holes? */
138: </PRE>
139:
140: <H3>Name of Remote login Host</H3>
141:
142: If an application is used for remote access (allowing telnet access,
143: like for example the Line Mode Browser), then set this variable to the
144: name of the remote host.
2.36 frystyk 145:
146: <PRE>
147: extern char * HTClientHost; /* Name or number of telnetting host */
2.52 frystyk 148: </PRE>
149:
150: <H3>Server Specific Flags</H3>
151:
152: These two flags are set by a proxy and a server application
153: respectfully. They tell the Library to skip some of the client
154: application specific things.
2.46 frystyk 155:
2.52 frystyk 156: <PRE>
2.36 frystyk 157: extern char * HTImServer; /* If I'm cern_httpd */
158: extern BOOL HTImProxy; /* If I'm cern_httpd as a proxy */
159: </PRE>
160:
2.52 frystyk 161: <H2><A NAME="z100">Functions to Manipulate a HTRequest Structure</A></H2>
162:
163: Just to make things easier especially for clients, here are some functions to
164: manipulate the request structure:
165:
166: <PRE>
167: typedef struct _HTRequest HTRequest;
168: </PRE>
169:
170: <H3>Create blank request</H3>
171:
172: This request has defaults in -- in most cases it will need some
173: information added before being passed to HTAccess, but it will work as
174: is for a simple request.
175:
176: <PRE>
177: extern HTRequest * HTRequest_new NOPARAMS;
178: </PRE>
179:
180: <H3>Delete request structure</H3>
181:
182: Frees also conversion list hanging from req->conversions.
183:
184: <PRE>
185: extern void HTRequest_delete PARAMS((HTRequest * req));
186: </PRE>
187:
188: <H3>Clear a request structure</H3>
189:
190: Clears a request structure so that it can be reused. The only thing
191: that differs from using free/new is that the list of conversions is
192: kept. <P>
2.41 frystyk 193:
2.52 frystyk 194: <B>NOTE:</B> It is <B>NOT</B> recommended to reuse a request structure!!!
2.41 frystyk 195:
196: <PRE>
2.52 frystyk 197: extern void HTRequest_clear PARAMS((HTRequest * req));
2.41 frystyk 198: </PRE>
199:
2.39 frystyk 200: <A NAME="Methods"><H2>Method Management</H2></A>
2.33 frystyk 201:
2.41 frystyk 202: These are the valid methods, see <A
2.46 frystyk 203: HREF="http://www.w3.org/hypertext/WWW/Protocols/HTTP/Methods.html">HTTP
204: Methods</A>. <P>
205:
206: <B>NOTE:</B> the anchor list of allowed methods are not a bitflag, not
207: at list.
2.33 frystyk 208:
209: <PRE>
2.16 luotonen 210: typedef enum {
2.46 frystyk 211: METHOD_INVALID = 0x0,
212: METHOD_GET = 0x1,
213: METHOD_HEAD = 0x2,
214: METHOD_POST = 0x4,
215: METHOD_PUT = 0x8,
216: METHOD_DELETE = 0x10,
217: METHOD_LINK = 0x20,
218: METHOD_UNLINK = 0x40
2.16 luotonen 219: } HTMethod;
2.33 frystyk 220: </PRE>
221:
222: <H3>Get Method Enumeration</H3>
2.16 luotonen 223:
2.33 frystyk 224: Gives the enumeration value of the method as a function of the (char *) name.
2.16 luotonen 225:
2.33 frystyk 226: <PRE>
2.46 frystyk 227: extern HTMethod HTMethod_enum PARAMS((CONST char * name));
2.16 luotonen 228: </PRE>
229:
2.33 frystyk 230: <H3>Get Method String</H3>
2.16 luotonen 231:
2.33 frystyk 232: The reverse of <I>HTMethod_enum()</I>
2.16 luotonen 233:
2.33 frystyk 234: <PRE>
2.46 frystyk 235: extern CONST char * HTMethod_name PARAMS((HTMethod method));
2.16 luotonen 236: </PRE>
2.33 frystyk 237:
2.52 frystyk 238: <A NAME="user"><H2>Local User Preferences</H2></A>
239:
240: These methods sets local user preferences for <EM>language</EM>,
241: <EM>media types</EM>, <EM>charsets</EM>, and <EM>encodings</EM> which
242: are added to the <A HREF="HTFormat.html#user">global set of
243: preferences</A>.
2.35 frystyk 244:
2.16 luotonen 245: <PRE>
2.52 frystyk 246: /* NOT FINISHED */
2.35 frystyk 247: </PRE>
2.46 frystyk 248:
2.52 frystyk 249: <H2>HTTP/MIME Header Methods</H2>
2.10 timbl 250:
2.52 frystyk 251: These enumerations set up the headers that are used in a HTTP request
252: <EM>OR</EM> a HTTP response.
2.10 timbl 253:
2.52 frystyk 254: <A NAME="HeaderMask"><H3>General HTTP Header Mask</H3></A>
2.46 frystyk 255:
2.51 frystyk 256: There are a few header fields which have general applicability for
257: both request and response mesages, but which do not apply to the
258: communication parties or theentity being transferred. This mask
259: enables and disables these headers. If the bit is not turned on they
2.52 frystyk 260: are not sent. All headers are optional and the default value is <EM>NO
261: GENERAL HEADERS</EM>
2.46 frystyk 262:
263: <PRE>
2.51 frystyk 264: typedef enum _GenHeaderEnum {
2.46 frystyk 265: HT_DATE = 0x1,
2.51 frystyk 266: HT_FORWARDED = 0x2,
267: HT_MESSAGE_ID = 0x4,
268: HT_MIME = 0x8
269: } GenHeaderEnum;
270:
271: #define <A NAME="DEF_HEAD">DEFAULT_GENERAL_HEADERS</A> 0
272: </PRE>
273:
2.52 frystyk 274: <H3>Request Headers</H3>
2.46 frystyk 275:
2.51 frystyk 276: The request header fields allow the client to pass additional
277: information about the request (and about the client itself) to the
278: server. All headers are optional but the default value is all request
279: headers if present <EM>except</EM> <CODE>From</CODE> and
280: <CODE>Pragma</CODE>.
281:
282: <PRE>
283: typedef enum _ReqHeaderEnum {
284: HT_ACCEPT_TYPE = 0x1,
285: HT_ACCEPT_CHAR = 0x2,
286: HT_ACCEPT_ENC = 0x4,
287: HT_ACCEPT_LAN = 0x8,
2.46 frystyk 288: HT_FROM = 0x10,
289: HT_PRAGMA = 0x20,
290: HT_REFERER = 0x40,
291: HT_USER_AGENT = 0x80
2.51 frystyk 292: } ReqHeaderEnum;
2.46 frystyk 293:
2.51 frystyk 294: #define <A NAME="DEF_REQ">DEFAULT_REQUEST_HEADERS</A> \
295: HT_ACCEPT_TYPE+HT_ACCEPT_CHAR+HT_ACCEPT_ENC+HT_ACCEPT_LAN+HT_REFERER+HT_USER_AGENT
2.46 frystyk 296: </PRE>
297:
2.52 frystyk 298: <H3>Entity Header Mask</H3>
2.46 frystyk 299:
300: The entity headers contain information about the object sent in the
301: HTTP transaction. See the <A HREF="HTAnchor.html">Anchor module</A>,
302: for the storage of entity headers. This flag defines which headers are
303: to be sent in a request together with an entity body (the <B>O</B>
2.51 frystyk 304: stands for <EM>object</EM>). All headers are optional but the default
305: value is <EM>ALL ENTITY HEADERS IF PRESENT</EM>
2.46 frystyk 306:
307: <PRE>
308: typedef enum _EntityHeaderEnum {
309: HT_ALLOW = 0x1,
310: HT_CONTENT_ENCODING = 0x2,
311: HT_CONTENT_LANGUAGE = 0x4,
312: HT_CONTENT_LENGTH = 0x8,
313: HT_CTE = 0x10, /* Content-Transfer-Encoding */
314: HT_CONTENT_TYPE = 0x20,
315: HT_DERIVED_FROM = 0x40,
316: HT_EXPIRES = 0x80,
317: HT_LAST_MODIFIED = 0x200,
318: HT_LINK = 0x400,
319: HT_TITLE = 0x800,
320: HT_URI = 0x1000,
321: HT_VERSION = 0x2000
322: } EntityHeaderEnum;
323:
2.51 frystyk 324: #define <A NAME="DEF_ENTITY">DEFAULT_ENTITY_HEADERS</A> 0xFFFF
2.46 frystyk 325: </PRE>
326:
2.52 frystyk 327: <H3>User Defined Headers</H3>
2.10 timbl 328:
2.52 frystyk 329: Extra header can be generated when initializing the <A
330: HREF="#ExtraHeaders">ExtraHeaders field</A>.
1.1 timbl 331:
2.52 frystyk 332: <A NAME="LoadDoc"><H2>Functions for Loading a Document</H2></A>
2.33 frystyk 333:
2.52 frystyk 334: There are several different ways of loading a document. However, the
335: major difference between them is whether the document is referenced by
2.33 frystyk 336:
2.52 frystyk 337: <UL>
338: <LI><A HREF="#Relative">Relative URI</A>
339: <LI><A HREF="#Absolute">Absolute URI</A>
340: <LI><A HREF="#Anchor">Anchor element</A> or
341: <LI>Contains keywords for <A HREF="#RelSearch">searching an relative URI</A>
342: <LI>Contains keywords for <A HREF="#AbsSearch">searching an absolute URI</A>
343: </UL>
2.33 frystyk 344:
2.52 frystyk 345: <B>NOTE:</B> From release 3.0 of the Library, the return codes from
346: the loading functions are no mode <CODE>BOOL</CODE>, that is
347: <CODE>YES</CODE> or <CODE>NO</CODE>. Insted they have been replaced
348: with the following set of return codes defined in the <A
349: HREF="HTUtils.html#ReturnCodes">Utility module</A>:
1.1 timbl 350:
2.52 frystyk 351: <DL>
352: <DT>HT_WOULD_BLOCK
353: <DD>An I/O operation would block
1.1 timbl 354:
2.52 frystyk 355: <DT>HT_ERROR
356: <DD>Error has occured
1.1 timbl 357:
2.52 frystyk 358: <DT>HT_LOADED
359: <DD>Success
2.23 frystyk 360:
2.52 frystyk 361: <DT>HT_NO_DATA
362: <DD>Success, but no document loaded. This might be the situation when a
363: telnet sesssion is started etc.
2.10 timbl 364:
2.52 frystyk 365: <DT>HT_RETRY
366: <DD>The remote server is down but will serve documents from the
367: calendar time indicated in HTRequest->retry_after.
2.51 frystyk 368:
2.52 frystyk 369: </DL>
2.51 frystyk 370:
2.52 frystyk 371: However, a general rule about the return codes is that <B>ERRORS</B>
372: have a <EM>negative</EM> value whereas <B>SUCCESS</B> has a
373: <EM>positive</EM> value. <P>
2.51 frystyk 374:
2.52 frystyk 375: There are also some functions to help the client getting started with
376: <A HREF="#ClientHelp">the first URI</A>.
2.51 frystyk 377:
2.52 frystyk 378: <A NAME="Relative"><H3>Load a document from relative URL</H3></A>
2.34 frystyk 379:
380: <PRE>
2.52 frystyk 381: extern int HTLoadRelative PARAMS((CONST char * relative_name,
382: HTParentAnchor* here,
383: HTRequest * request));
2.34 frystyk 384: </PRE>
385:
2.52 frystyk 386: <A NAME="Absolute"></A><H3>Load a document from absolute URL</H3>
2.39 frystyk 387:
388: <PRE>
2.52 frystyk 389: extern int HTLoadAbsolute PARAMS((CONST char * addr,
390: HTRequest * request));
2.39 frystyk 391: </PRE>
2.19 timbl 392:
2.52 frystyk 393: <H3>Load a document from absolute name to a stream</H3>
2.19 timbl 394:
2.39 frystyk 395: <PRE>
2.52 frystyk 396: extern int HTLoadToStream PARAMS((CONST char * addr,
397: BOOL filter,
398: HTRequest * request));
2.39 frystyk 399: </PRE>
400:
2.52 frystyk 401: <A NAME="Anchor"><H3>Load a document from anchor</H3></A>
2.46 frystyk 402:
2.52 frystyk 403: The anchor parameter may be a child anchor. The anchor in the request
404: is set to the parent anchor. The recursive function keeps the error
405: stack in the request structure so that no information is lost having
406: more than one call. See also <A HREF="#BindAnchor">HTBindAnchor()</A>.
2.39 frystyk 407:
408: <PRE>
2.52 frystyk 409: extern int HTLoadAnchor PARAMS((HTAnchor * a,
410: HTRequest * request));
411: extern int HTLoadAnchorRecursive PARAMS((HTAnchor * a,
412: HTRequest * request));
2.39 frystyk 413: </PRE>
414:
2.52 frystyk 415: <H3>Load a Document</H3>
2.39 frystyk 416:
2.52 frystyk 417: These are two internal routines for loading a document which has an
418: address AND a matching anchor. (The public routines are called with
419: one OR the other.) This is recursively called from file load module
420: to try ftp (though this will be obsolete in the next major
421: release).<P>
2.39 frystyk 422:
2.52 frystyk 423: If <CODE>keep_error_stack</CODE> is YES then the error (or info) stack
424: is not cleared from the previous call.
2.39 frystyk 425:
426: <PRE>
2.52 frystyk 427: extern int HTLoad PARAMS((HTRequest * request,
428: BOOL keep_error_stack));
2.39 frystyk 429: </PRE>
430:
431: <PRE>
2.52 frystyk 432: extern BOOL HTLoadTerminate PARAMS((HTRequest * request, int status));
2.51 frystyk 433: </PRE>
434:
2.52 frystyk 435: <A NAME="RelSearch"><H3>Search Using Relative URL</H3></A>
436:
437: Performs a search on word given by the user. Adds the search words to
438: the end of the current address and attempts to open the new address.
2.51 frystyk 439:
440: <PRE>
2.52 frystyk 441: extern int HTSearch PARAMS((CONST char * keywords,
442: HTParentAnchor* here,
443: HTRequest * request));
2.46 frystyk 444: </PRE>
445:
2.52 frystyk 446: <A NAME="AbsSearch"><H3>Search using Absolute URL</H3></A>
447:
448: Performs a keyword search on word given by the user. Adds the keyword
449: to the end of the current address and attempts to open the new
450: address.
2.46 frystyk 451:
452: <PRE>
2.52 frystyk 453: extern int HTSearchAbsolute PARAMS((CONST char * keywords,
454: CONST char * indexname,
455: HTRequest * request));
2.46 frystyk 456: </PRE>
457:
458:
2.52 frystyk 459: <A NAME="ClientHelp"><H2>Help Function for Clients to get started</H2></A>
2.39 frystyk 460:
2.52 frystyk 461: These function helps the client to load the first document. They are
462: not mandatory to use - but they make life easier!
2.46 frystyk 463:
2.52 frystyk 464: <A NAME="BindAnchor"><H3>Bind an anchor to a request structure without
465: loading</H3></A>
2.39 frystyk 466:
467: <PRE>
2.52 frystyk 468: extern BOOL HTBindAnchor PARAMS((HTAnchor *anchor, HTRequest *request));
2.39 frystyk 469: </PRE>
470:
2.52 frystyk 471: <A NAME="HomePage"><H3>Generate the Anchor for the Home Page</H3></A>
472:
473: As it involves file access, this should only be done once when the
474: program first runs. This is a default algorithm using the
475: <CODE>WWW_HOME</CODE> environment variable.
2.39 frystyk 476:
477: <PRE>
2.52 frystyk 478: extern HTParentAnchor * HTHomeAnchor NOPARAMS;
2.39 frystyk 479: </PRE>
480:
2.52 frystyk 481: <H3>Find Related Name</H3>
2.45 frystyk 482:
2.52 frystyk 483: Creates a local file URI that can be used as a relative name when
484: calling HTParse() to expand a relative file name to an absolute
485: one. <P>
2.45 frystyk 486:
2.52 frystyk 487: The code for this routine originates from the Line Mode Browser and
2.53 ! frystyk 488: was moved here by <EM>howcome@w3.org</EM> in order for all
2.52 frystyk 489: clients to take advantage.<P>
2.39 frystyk 490:
2.47 frystyk 491: <PRE>
2.52 frystyk 492: extern char * HTFindRelatedName NOPARAMS;
2.47 frystyk 493: </PRE>
494:
2.52 frystyk 495: <A NAME="PostDoc"><H2>Functions for Posting a Document</H2></A>
496:
497: <B>NOTE:</B> The Posting functions are used to send a data object
498: along with the request. The functions have the same set of return
499: codes as for the <A HREF="#LoadDoc">Load Functions</A>.
2.47 frystyk 500:
2.52 frystyk 501: <H3>Get a Save Stream</H3>
2.46 frystyk 502:
2.52 frystyk 503: <H4>On Entry,</H4>
504: <DL>
505: <DT>request->anchor
506: <DD> is valid anchor which
507: has previously beeing loaded
508: </DL>
2.46 frystyk 509:
2.52 frystyk 510: <H4>On exit,</H4>
511: <DL>
512: <DT>returns
513: <DD> 0 if error else a stream
514: to save the object to.
515: </DL>
2.46 frystyk 516:
517: <PRE>
2.52 frystyk 518: extern HTStream * HTSaveStream PARAMS((HTRequest * request));
2.46 frystyk 519: </PRE>
520:
2.52 frystyk 521: <H3>Copy an Anchor</H3>
522:
523: Fetch the URL (possibly local file URL) and send it using either
524: <B>PUT</B> or <B>POST</B> directly to the remote destination using
525: HTTP, that is remote copy of object <EM>O</EM> from <EM>A</EM> to
526: <EM>B</EM> where <EM>A</EM> might be the host of the application. The
527: caller can decide the exact method used and which HTTP header fields
528: to transmit by setting the user fields in the destination request
529: structure.
2.46 frystyk 530:
531: <PRE>
2.52 frystyk 532: extern int HTCopyAnchor PARAMS((HTAnchor * src_anchor,
533: HTParentAnchor *dest_anchor,
534: HTRequest * dest_req));
2.39 frystyk 535: </PRE>
536:
2.46 frystyk 537:
2.52 frystyk 538: <H3>Upload an Anchor</H3>
2.39 frystyk 539:
2.52 frystyk 540: Send the contents (in hyperdoc) of the source anchor using either
541: <B>PUT</B> or <B>POST</B> to the remote destination using HTTP. The
542: caller can decide the exact method used and which HTTP header fields
543: to transmit by setting the user fields in the request structure.
544: <EM>Format conversion</EM> can be made on the fly by setting the <A
545: HREF="#input_format">input_format field</A> in the destination request
546: structure. If the content-length is unknown (-1) then a <A
547: HREF="HTConLen.html">content-length counter</A> is automaticly put
548: into the stream pipe.
2.43 frystyk 549:
550:
551: <PRE>
2.52 frystyk 552: extern int HTUploadAnchor PARAMS((HTAnchor * src_anchor,
553: HTParentAnchor *dest_anchor,
554: HTRequest * dest_req));
2.46 frystyk 555: </PRE>
556:
557:
2.52 frystyk 558: <A NAME="ProtReg"><H2>Access Method Registration</H2></A>
2.39 frystyk 559:
2.52 frystyk 560: An access method is defined by an HTProtocol structure which point to
561: the routines for performing the various logical operations on an
562: object: in HTTP terms, GET, PUT, and POST. The access methods
563: supported in the Library are initiated automaticly using the private
564: function <CODE>HTAccessInit()</CODE> <B>if not</B> defined
565: <CODE>HT_NO_INIT</CODE> <P>
2.39 frystyk 566:
2.52 frystyk 567: Each of these routine takes as a parameter a <A NAME="z2"
568: HREF="#z1">request structure</A> containing details of the request.
569: When the protocol class routine is called, the anchor element in the
570: request is already valid (made valid by HTAccess).
2.39 frystyk 571:
572: <PRE>
2.52 frystyk 573: typedef enum _HTSocBlock {
574: SOC_BLOCK,
575: SOC_NON_BLOCK
576: } HTSocBlock;
2.39 frystyk 577:
2.52 frystyk 578: typedef struct _HTProtocol {
579: char * name;
580: HTSocBlock block;
581: int (*load) PARAMS((HTRequest * request));
582: HTStream* (*saveStream) PARAMS((HTRequest * request));
583: HTStream* (*postStream) PARAMS((HTRequest * request,
584: HTParentAnchor* postTo));
585: } HTProtocol;
2.39 frystyk 586:
2.52 frystyk 587: extern BOOL HTRegisterProtocol PARAMS((HTProtocol * protocol));
588: extern void HTDisposeProtocols NOPARAMS;
2.39 frystyk 589: </PRE>
590:
2.52 frystyk 591: <H3>Uses Protocol Blocking IO</H3>
592:
593: A small function to make life easier. Returns <CODE>YES</CODE> or
594: <CODE>NO</CODE>. If the Library is run in NON-INTERACTIVE MODE then
595: the function always returns YES;
2.39 frystyk 596:
597: <PRE>
2.52 frystyk 598: extern BOOL HTProtocolBlocking PARAMS((HTRequest * request));
2.46 frystyk 599: </PRE>
600:
2.52 frystyk 601: <A NAME="Int"><H2>Internal Data Structures</H2></A>
602:
603: These are internal to the Library and should not normally be accessed
604: directly.
2.46 frystyk 605:
2.52 frystyk 606: <H3>Access Authentication</H3>
2.39 frystyk 607:
2.52 frystyk 608: We need to define the following structures as they are used in the
609: HTRequest structure. The AA module is declared in <A
610: HREF="HTAAUtil.html">HTAAUtil</A> and <A HREF="HTAABrow.html">
611: HTAABrow</A>. The enumeration <CODE>HTAAScheme </CODE>represents the
612: possible authentication schemes used by the WWW Access Authorization.
2.19 timbl 613:
2.25 luotonen 614: <PRE>
2.52 frystyk 615: typedef enum {
616: HTAA_UNKNOWN,
617: HTAA_NONE,
618: HTAA_BASIC,
619: HTAA_PUBKEY,
620: HTAA_KERBEROS_V4,
621: HTAA_KERBEROS_V5,
622: HTAA_MAX_SCHEMES /* THIS MUST ALWAYS BE LAST! */
623: } HTAAScheme;
624:
625: typedef struct _HTAARealm HTAARealm;
626: typedef struct _HTAASetup HTAASetup;
2.46 frystyk 627: </PRE>
2.25 luotonen 628:
2.52 frystyk 629: <A NAME="socket"><H3>Buffering for the network</H3></A>
630:
631: This structure provides buffering for READ (and future WRITE) to the
632: network. It is used by all the protocol modules. The size of the
633: buffer, <CODE>INPUT_BUFFER_SIZE</CODE>, is a compromis between speed
634: and memory.
2.46 frystyk 635:
636: <PRE>
2.52 frystyk 637: #define INPUT_BUFFER_SIZE 8192
638:
639: typedef struct _HTInputSocket HTInputSocket;
2.34 frystyk 640: </PRE>
2.46 frystyk 641:
2.52 frystyk 642: <H3><A NAME="HTNetInfo">Protocol Specific Information</A></H3>
643:
644: This structure contains information about socket number, input buffer
645: for reading from the network etc. The structure is used through out
646: the protocol modules and is the reference point for introducing multi
647: threaded execution into the library, see specifications on <A
648: HREF="http://www.w3.org/hypertext/WWW/Library/User/Features/multithread.html">Multiple
649: Threads</A>.
2.46 frystyk 650:
2.34 frystyk 651: <PRE>
2.52 frystyk 652: typedef enum _SocAction {
653: SOC_INVALID = -1,
654: SOC_WRITE = 0, /* By default ready to write */
655: SOC_READ,
656: SOC_INTERRUPT
657: } SocAction;
658:
659: typedef struct _HTNetInfo {
660: SOCKFD sockfd; /* Socket descripter */
661: SockA sock_addr; /* SockA is defined in tcp.h */
662: HTInputSocket * isoc; /* Input buffer */
663: SocAction action; /* Result of the select call */
664: HTStream * target; /* Target stream */
665: int addressCount; /* Attempts if multi-homed host */
666: time_t connecttime; /* Used on multihomed hosts */
667: struct _HTRequest * request; /* Link back to request structure */
668: } HTNetInfo;
2.25 luotonen 669: </PRE>
2.39 frystyk 670:
2.52 frystyk 671: <EM><B>Note:</B> The AddressCount varaible is used to count the number
672: of attempt to connect to a multi-homed host so we know when to stop
673: trying new IP-addresses.</EM>
674:
675: <H3><A NAME="z1">The Request structure</A></H3>
2.46 frystyk 676:
2.52 frystyk 677: When a request is handled, all kinds of things about it need to be
678: passed along. These are all put into a HTRequest structure. This is
679: the most essential structure in the library. It contains two main
680: categories of information regarding a request:
2.39 frystyk 681:
2.52 frystyk 682: <UL>
683: <LI>Application dependent information
684: <LI>Library dependent information
685: </UL>
2.46 frystyk 686:
2.52 frystyk 687: Applications using the Library should <EM>never</EM> use the internal
688: library dependent information. It's only because we dont have real
689: classes that we can't hide it. <P>
2.46 frystyk 690:
2.52 frystyk 691: <B>Note:</B> If you reuse the request structure for more than one
692: request then make sure that the request is re-initialized, so that no
693: `old' data is reused, see <A HREF="#z100">functions to manipulate
694: HTRequest Structure</A>. The library handles its own internal
695: information from request to request but the information set by the
696: caller is untouched. <P>
2.46 frystyk 697:
2.52 frystyk 698: The elements of the request structure are as follows:
2.49 frystyk 699:
700: <PRE>
2.52 frystyk 701: struct _HTRequest {
2.49 frystyk 702: </PRE>
703:
2.52 frystyk 704: <H4>Application Dependent - Set by the caller of HTAccess</H4>
705:
2.19 timbl 706: <PRE>
2.52 frystyk 707: <A HREF="#Methods">HTMethod</A> method;
2.31 frystyk 708: </PRE>
709:
2.52 frystyk 710: An enum used to specify the HTTP <A NAME="z7"
711: HREF="../../Protocols/HTTP/Methods.html">method</A> used for the
712: actual request. The default value is <A
713: HREF="#Methods"><CODE>GET</CODE></A>.
2.31 frystyk 714:
2.52 frystyk 715: <H5>HTTP Header Information</H5>
2.31 frystyk 716:
2.14 luotonen 717: <PRE>
2.52 frystyk 718: HTList * conversions;
2.31 frystyk 719: </PRE>
2.14 luotonen 720:
2.52 frystyk 721: NULL, or a <EM>local</EM> list of specific conversions which the
722: format manager can do in order to fulfill the request. It typically
723: points to a list set up on initialisation time for example by <A
724: HREF="HTInit.html">HTInit()</A>. There is also a <A
725: HREF="HTFormat.html#z17"><EM>global</EM></A> list of conversions which
726: contains a generic set of possible conversions.
727:
2.14 luotonen 728: <PRE>
2.52 frystyk 729: HTList * encodings;
2.31 frystyk 730: </PRE>
1.1 timbl 731:
2.52 frystyk 732: The list of encodings acceptable in the output stream.
2.46 frystyk 733:
2.52 frystyk 734: <PRE>
735: HTList * languages;
736: </PRE>
2.46 frystyk 737:
2.52 frystyk 738: The list of (human) language values acceptable in the response. The default
739: is all languages.
2.46 frystyk 740:
2.31 frystyk 741: <PRE>
2.52 frystyk 742: HTList * charsets;
2.31 frystyk 743: </PRE>
2.9 timbl 744:
2.52 frystyk 745: The list of charsets accepted by the application
2.39 frystyk 746:
2.52 frystyk 747: <PRE>
748: GenHeaderEnum GenMask;
749: ReqHeaderEnum RequestMask;
750: EntityHeaderEnum EntityMask;
751: </PRE>
2.39 frystyk 752:
2.52 frystyk 753: These bitmask variables defines which headers to include in a HTTP
754: request (or any other MIME-like protocol). See <A
755: HREF="#HeaderMask">header masks</A> for more information on default
756: values.
2.39 frystyk 757:
2.52 frystyk 758: <PRE>
759: HTParentAnchor *parentAnchor;
760: </PRE>
2.39 frystyk 761:
2.52 frystyk 762: If this parameter is set then a `Referer: <parent address> can
763: be generated in the request to the server, see <A
764: HREF="http://www.w3.org/hypertext/WWW/Protocols/HTTP/HTRQ_Headers.html#z14">
765: Referer field in a HTTP Request</A>
2.39 frystyk 766:
2.52 frystyk 767: <PRE>
768: <A NAME="ExtraHeaders">char * ExtraHeaders;</A>
769: </PRE>
2.39 frystyk 770:
2.52 frystyk 771: Extra header information can be send along with a request using this
772: variable. The text is sent as is so it must be preformatted with
773: <CRLF> line terminators.
2.47 frystyk 774:
2.52 frystyk 775: <H5>Streams From Network to Application</H5>
1.1 timbl 776:
2.39 frystyk 777: <PRE>
2.52 frystyk 778: HTStream * output_stream;
2.5 timbl 779: </PRE>
2.39 frystyk 780:
2.52 frystyk 781: The output stream is to be used to put data down to as they come in
782: <B>from</B> the network and back to the application. The default value
783: is <CODE>NULL</CODE> which means that the stream goes to the user
784: (display).
1.1 timbl 785:
2.5 timbl 786: <PRE>
2.52 frystyk 787: HTAtom * output_format;
2.5 timbl 788: </PRE>
2.39 frystyk 789:
2.52 frystyk 790: The desired format of the output stream. This can be used to get
791: unconverted data etc. from the library. If <CODE>NULL</CODE>, then <A
792: HREF="HTFormat.html#FormatTypes">WWW_PRESENT</A> is default value.
2.39 frystyk 793:
2.5 timbl 794: <PRE>
2.52 frystyk 795: HTStream* error_stream;
2.5 timbl 796: </PRE>
1.1 timbl 797:
2.52 frystyk 798: All object bodies sent from the server with status codes different
799: from <CODE>200 OK</CODE> will be put down this stream. This can be
800: used as a debug window etc. If the value is NULL (default) then the
801: stream used is <A HREF="HTFormat.html#BlackHole">HTBlackHole</A>.
1.1 timbl 802:
2.39 frystyk 803: <PRE>
2.52 frystyk 804: HTAtom * error_format;
2.5 timbl 805: </PRE>
806:
2.52 frystyk 807: The desired format of the error stream. This can be used to get
808: unconverted data etc. from the library. The default value if
809: <CODE>WWW_HTML</CODE> as a character based only has one WWW_PRESENT.
1.1 timbl 810:
2.52 frystyk 811: <H5>Streams From Application to Network</H5>
1.1 timbl 812:
2.39 frystyk 813: <PRE>
2.52 frystyk 814: HTStream * input_stream;
2.41 frystyk 815: </PRE>
816:
2.52 frystyk 817: The input stream is to be used by the <CODE>PostCallBack</CODE>
818: function to put data out on the network. The user should not
819: initialize this field.
820:
2.41 frystyk 821: <PRE>
2.52 frystyk 822: HTAtom * input_format;
2.5 timbl 823: </PRE>
824:
2.52 frystyk 825: The desired format of the output stream. This can be used to upload
826: converted data to a remote server. If <CODE>NULL</CODE>, then <A
827: HREF="HTFormat.html#FormatTypes">WWW_SOURCE</A> is default value.
2.39 frystyk 828:
2.5 timbl 829: <PRE>
2.52 frystyk 830: int (*PostCallBack) PARAMS((struct _HTRequest * request,
831: HTStream * target));
2.5 timbl 832: </PRE>
2.39 frystyk 833:
2.52 frystyk 834: The call back function which is called when the current request is
835: ready for sending (posting) the data object. The request is the
836: current request so that the application knows which post we are
837: handling. The function must have the same return values as the other
838: <A HREF="#LoadDoc">Load functions</A>.
2.39 frystyk 839:
2.52 frystyk 840: <H5>Other Flags</H5>
2.5 timbl 841:
2.33 frystyk 842: <PRE>
2.52 frystyk 843: BOOL BlockingIO;
844: BOOL ForceReload;
845: BOOL ContentNegotiation;
2.5 timbl 846: </PRE>
2.24 luotonen 847:
2.52 frystyk 848: <CODE>BlockingIO</CODE> can be set to override if a protocol module is
849: registered as using non-blocking IO, <CODE>ForceReload</CODE> will
850: cancel any cached element, and <CODE>ContentNegotioation</CODE> will
851: force content negotiation when looking for a local file. This is the
852: default!
2.24 luotonen 853:
854: <PRE>
2.52 frystyk 855: BOOL (*<A NAME="z9"> callback</A> ) PARAMS((struct _HTRequest* request,
856: void *param));
2.24 luotonen 857: </PRE>
858:
2.52 frystyk 859: A function to be called back in the event that a file has been saved
860: to disk by HTSaveAndCallBack for example.
2.20 frystyk 861:
862: <PRE>
2.52 frystyk 863: void * context;
2.39 frystyk 864: </PRE>
865:
2.52 frystyk 866: An arbitrary pointer passed to HTAccess and passed back as a parameter
867: to the <A NAME="z10" HREF="#z9">callback</A>.
2.39 frystyk 868:
2.52 frystyk 869: <H4>Library Dependent - Set by Library</H4>
2.39 frystyk 870:
2.52 frystyk 871: None of the bits below may be looked at by a WWW application. The
872: Library handles the cleanup by itself.
2.39 frystyk 873:
2.20 frystyk 874: <PRE>
2.52 frystyk 875: HTParentAnchor* anchor;
2.39 frystyk 876: </PRE>
877:
2.52 frystyk 878: The anchor for the object in question. Set immediately by HTAcesss.
879: Used by the protocol and parsing modules. Valid thoughout the access.
2.39 frystyk 880:
2.52 frystyk 881: <PRE>
882: HTChildAnchor * childAnchor; /* For element within the object */
883: </PRE>
2.20 frystyk 884:
2.52 frystyk 885: The anchor for the sub object if any. The object builder should
886: ensure that is is selected, highlighted, etc when the object is
887: loaded.
2.20 frystyk 888:
2.52 frystyk 889: <PRE>
890: void * using_cache;
891: BOOL using_proxy;
892: </PRE>
2.5 timbl 893:
2.52 frystyk 894: Pointer to cache element if cache hit anfd if using proxy
2.5 timbl 895:
896: <PRE>
2.52 frystyk 897: BOOL error_block; /* YES if stream has been used */
898: HTList * error_stack; /* List of errors */
2.46 frystyk 899: </PRE>
900:
2.52 frystyk 901: These two fields are used by the error reporting system to keep a
902: stack of messages.
2.46 frystyk 903:
904: <PRE>
2.52 frystyk 905: HTNetInfo * net_info; /* Information about socket etc. */
906: int redirections; /* Number of redirections */
907: time_t retry_after; /* Absolut time for a retry */
908: HTRequest * CopyRequest;
909: BOOL Source; /* Yes if we are a "CopyRequest" */
2.46 frystyk 910: </PRE>
911:
2.52 frystyk 912: Protocol specific information, socket number etc.
2.46 frystyk 913:
2.52 frystyk 914: <PRE>
915: char * redirect; /* Location or URI */
916: char * WWWAAScheme; /* WWW-Authenticate scheme */
917: char * WWWAARealm; /* WWW-Authenticate realm */
918: char * WWWprotection; /* WWW-Protection-Template */
919: </PRE>
2.46 frystyk 920:
2.52 frystyk 921: Information taken from the MIME header specifically oriented towards
922: the request (not the object itself)
2.46 frystyk 923:
924: <PRE>
2.52 frystyk 925: char * authorization; /* Authorization: field */
926: HTAAScheme scheme; /* Authentication scheme used */
927: HTInputSocket * isoc; /* InputSocket object for reading */
2.39 frystyk 928: </PRE>
2.5 timbl 929:
2.52 frystyk 930: These header fields are only used by the server and will be removed at some
931: point.
1.1 timbl 932:
2.52 frystyk 933: <PRE>
934: HTList * valid_schemes; /* Valid auth.schemes */
935: HTAssocList ** scheme_specifics;/* Scheme-specific parameters */
936: char * authenticate; /* WWW-authenticate: field */
937: char * prot_template; /* WWW-Protection-Template: field */
938: HTAASetup * setup; /* Doc protection info */
939: HTAARealm * realm; /* Password realm */
940: char * dialog_msg; /* Authentication prompt (client) */
941: </PRE>
1.1 timbl 942:
2.52 frystyk 943: These fields are used by the HTTP access authentication used by a
944: client application.
2.39 frystyk 945:
2.52 frystyk 946: <H4>Windows Specific Information</H4>
2.39 frystyk 947:
948: <PRE>
2.52 frystyk 949: #ifdef _WINDOWS
950: HWND hwnd; /* Windows handle for MSWindows */
951: unsigned long winMsg; /* msg number of Windows eloop */
952: #endif /* _WINDOWS */
2.5 timbl 953: </PRE>
1.1 timbl 954:
2.38 howcome 955: <PRE>
2.52 frystyk 956: };
2.38 howcome 957: </PRE>
958:
2.52 frystyk 959: End of Declaration
2.25 luotonen 960:
961: <PRE>
1.1 timbl 962: #endif /* HTACCESS_H */
2.25 luotonen 963: </PRE>
964: end of HTAccess
965: </BODY>
2.9 timbl 966: </HTML>
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