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Diffstat (limited to 'WWW/Library/Implementation/HTFormat.h')
| -rw-r--r-- | WWW/Library/Implementation/HTFormat.h | 548 |
1 files changed, 548 insertions, 0 deletions
diff --git a/WWW/Library/Implementation/HTFormat.h b/WWW/Library/Implementation/HTFormat.h new file mode 100644 index 00000000..1e82fd76 --- /dev/null +++ b/WWW/Library/Implementation/HTFormat.h @@ -0,0 +1,548 @@ +/* + * $LynxId: HTFormat.h,v 1.33 2010/10/27 00:13:53 tom Exp $ + * + * HTFormat: The format manager in the WWW Library + * MANAGE DIFFERENT DOCUMENT FORMATS + * + * Here we describe the functions of the HTFormat module which handles conversion between + * different data representations. (In MIME parlance, a representation is known as a + * content-type. In WWW the term "format" is often used as it is shorter). + * + * This module is implemented by HTFormat.c. This hypertext document is used to generate + * the HTFormat.h include file. Part of the WWW library. + */ +#ifndef HTFORMAT_H +#define HTFORMAT_H + +#include <HTStream.h> +#include <HTAtom.h> +#include <HTList.h> +#include <HTAnchor.h> + +#ifdef USE_SOURCE_CACHE +#include <HTChunk.h> +#endif + +#ifdef USE_BZLIB +#include <bzlib.h> +#endif + +#ifdef USE_ZLIB +#include <zlib.h> +#endif + +#ifdef __cplusplus +extern "C" { +#endif +/* + + These macros (which used to be constants) define some basic internally + referenced representations. The www/xxx ones are of course not MIME + standard. + + www/source is an output format which leaves the input untouched. It is + useful for diagnostics, and for users who want to see the original, whatever + it is. + + */ +/* Internal ones */ +/* #define WWW_SOURCE HTAtom_for("www/source") */ +/* Whatever it was originally */ + extern HTAtom *WWW_SOURCE; + /* calculated once, heavy used */ + +/* + + www/present represents the user's perception of the document. If you + convert to www/present, you present the material to the user. + + */ +#define WWW_PRESENT HTAtom_for("www/present") /* The user's perception */ + +#define WWW_DEBUG HTAtom_for("www/debug") +/* + + WWW_DEBUG represents the user's perception of debug information, for example + sent as a HTML document in a HTTP redirection message. + + */ + +/* + + The message/rfc822 format means a MIME message or a plain text message with + no MIME header. This is what is returned by an HTTP server. + + */ +#define WWW_MIME HTAtom_for("www/mime") /* A MIME message */ + +/* + For parsing only the header. - kw + */ +#define WWW_MIME_HEAD HTAtom_for("message/x-rfc822-head") + +/* + + www/print is like www/present except it represents a printed copy. + + */ +#define WWW_PRINT HTAtom_for("www/print") /* A printed copy */ + +/* + + www/unknown is a really unknown type. Some default action is appropriate. + + */ +#define WWW_UNKNOWN HTAtom_for("www/unknown") + +#ifdef DIRED_SUPPORT +/* + www/dired signals directory edit mode. +*/ +#define WWW_DIRED HTAtom_for("www/dired") +#endif + +/* + + These are regular MIME types. HTML is assumed to be added by the W3 code. + application/octet-stream was mistakenly application/binary in earlier libwww + versions (pre 2.11). + + */ +#define WWW_PLAINTEXT HTAtom_for("text/plain") +#define WWW_POSTSCRIPT HTAtom_for("application/postscript") +#define WWW_RICHTEXT HTAtom_for("application/rtf") +#define WWW_AUDIO HTAtom_for("audio/basic") +#define WWW_HTML HTAtom_for("text/html") +#define WWW_BINARY HTAtom_for("application/octet-stream") + + typedef HTAtom *HTEncoding; + +/* + * The following are values for the MIME types: + */ +#define WWW_ENC_7BIT HTAtom_for("7bit") +#define WWW_ENC_8BIT HTAtom_for("8bit") +#define WWW_ENC_BINARY HTAtom_for("binary") + +/* + * We also add + */ +#define WWW_ENC_COMPRESS HTAtom_for("compress") + +/* + * Does a string designate a real encoding, or is it just + * a "dummy" as for example 7bit, 8bit, and binary? + */ +#define IsUnityEncStr(senc) \ + ((senc)==NULL || *(senc)=='\0' || !strcmp(senc,"identity") ||\ + !strcmp(senc,"8bit") || !strcmp(senc,"binary") || !strcmp(senc,"7bit")) + +#define IsUnityEnc(enc) \ + ((enc)==NULL || (enc)==HTAtom_for("identity") ||\ + (enc)==WWW_ENC_8BIT || (enc)==WWW_ENC_BINARY || (enc)==WWW_ENC_7BIT) + +/* + +The HTPresentation and HTConverter types + + This HTPresentation structure represents a possible conversion algorithm + from one format to another. It includes a pointer to a conversion routine. + The conversion routine returns a stream to which data should be fed. See + also HTStreamStack which scans the list of registered converters and calls + one. See the initialisation module for a list of conversion routines. + + */ + typedef struct _HTPresentation HTPresentation; + + typedef HTStream *HTConverter (HTPresentation *pres, + HTParentAnchor *anchor, + HTStream *sink); + + struct _HTPresentation { + HTAtom *rep; /* representation name atomized */ + HTAtom *rep_out; /* resulting representation */ + HTConverter *converter; /* routine to gen the stream stack */ + char *command; /* MIME-format command string */ + char *testcommand; /* MIME-format test string */ + float quality; /* Between 0 (bad) and 1 (good) */ + float secs; + float secs_per_byte; + off_t maxbytes; + BOOL get_accept; /* list in "Accept:" for GET */ + int accept_opt; /* matches against LYAcceptMedia */ + }; + +/* + + The list of presentations is kept by this module. It is also scanned by + modules which want to know the set of formats supported. for example. + + */ + extern HTList *HTPresentations; + +/* + + The default presentation is used when no other is appropriate + + */ + extern HTPresentation *default_presentation; + +/* + * Options used for "Accept:" string + */ + typedef enum { + /* make the components powers of two so we can add them */ + mediaINT = 1 /* internal types predefined in HTInit.c */ + ,mediaEXT = 2 /* external types predefined in HTInit.c */ + ,mediaCFG = 4 /* types, e.g., viewers, from lynx.cfg */ + ,mediaUSR = 8 /* user's mime-types, etc. */ + ,mediaSYS = 16 /* system's mime-types, etc. */ + /* these are useful flavors for the options menu */ + ,mediaOpt1 = mediaINT + ,mediaOpt2 = mediaINT + mediaCFG + ,mediaOpt3 = mediaINT + mediaCFG + mediaUSR + ,mediaOpt4 = mediaINT + mediaCFG + mediaUSR + mediaSYS + /* this is the flavor from pre-2.8.6 */ + ,mediaALL = mediaINT + mediaEXT + mediaCFG + mediaUSR + mediaSYS + } AcceptMedia; + +/* + * Options used for "Accept-Encoding:" string + */ + typedef enum { + encodingNONE = 0 + ,encodingGZIP = 1 + ,encodingDEFLATE = 2 + ,encodingCOMPRESS = 4 + ,encodingBZIP2 = 8 + ,encodingALL = (encodingGZIP + + encodingDEFLATE + + encodingCOMPRESS + + encodingBZIP2) + } AcceptEncoding; + +/* + +HTSetPresentation: Register a system command to present a format + + ON ENTRY, + + rep is the MIME - style format name + + command is the MAILCAP - style command template + + testcommand is the MAILCAP - style testcommand template + + quality A degradation faction 0..1.0 + + secs A limit on the time user will wait (0.0 for infinity) + secs_per_byte + + maxbytes A limit on the length acceptable as input (0 infinite) + + media Used in filtering presentation types for "Accept:" + + */ + extern void HTSetPresentation(const char *representation, + const char *command, + const char *testcommand, + double quality, + double secs, + double secs_per_byte, + long int maxbytes, + AcceptMedia media + ); + +/* + +HTSetConversion: Register a converstion routine + + ON ENTRY, + + rep_in is the content-type input + + rep_out is the resulting content-type + + converter is the routine to make the stream to do it + + */ + + extern void HTSetConversion(const char *rep_in, + const char *rep_out, + HTConverter *converter, + double quality, + double secs, + double secs_per_byte, + long int maxbytes, + AcceptMedia media + ); + +/* + +HTStreamStack: Create a stack of streams + + This is the routine which actually sets up the conversion. It currently + checks only for direct conversions, but multi-stage conversions are forseen. + It takes a stream into which the output should be sent in the final format, + builds the conversion stack, and returns a stream into which the data in the + input format should be fed. The anchor is passed because hypertxet objects + load information into the anchor object which represents them. + + */ + extern HTStream *HTStreamStack(HTFormat format_in, + HTFormat format_out, + HTStream *stream_out, + HTParentAnchor *anchor); + +/* +HTReorderPresentation: put presentation near head of list + + Look up a presentation (exact match only) and, if found, reorder it to the + start of the HTPresentations list. - kw + */ + + extern void HTReorderPresentation(HTFormat format_in, + HTFormat format_out); + +/* + * Setup 'get_accept' flag to denote presentations that are not redundant, + * and will be listed in "Accept:" header. + */ + extern void HTFilterPresentations(void); + +/* + +HTStackValue: Find the cost of a filter stack + + Must return the cost of the same stack which HTStreamStack would set up. + + ON ENTRY, + + format_in The fomat of the data to be converted + + format_out The format required + + initial_value The intrinsic "value" of the data before conversion on a scale + from 0 to 1 + + length The number of bytes expected in the input format + + */ + extern float HTStackValue(HTFormat format_in, + HTFormat rep_out, + double initial_value, + long int length); + +#define NO_VALUE_FOUND -1e20 /* returned if none found */ + +/* Display the page while transfer in progress + * ------------------------------------------- + * + * Repaint the page only when necessary. + * This is a traverse call for HText_pageDispaly() - it works!. + * + */ + extern void HTDisplayPartial(void); + + extern void HTFinishDisplayPartial(void); + +/* + +HTCopy: Copy a socket to a stream + + This is used by the protocol engines to send data down a stream, typically + one which has been generated by HTStreamStack. + + */ + extern int HTCopy(HTParentAnchor *anchor, + int file_number, + void *handle, + HTStream *sink); + +/* + +HTFileCopy: Copy a file to a stream + + This is used by the protocol engines to send data down a stream, typically + one which has been generated by HTStreamStack. It is currently called by + HTParseFile + + */ + extern int HTFileCopy(FILE *fp, + HTStream *sink); + +#ifdef USE_SOURCE_CACHE +/* + +HTMemCopy: Copy a memory chunk to a stream + + This is used by the protocol engines to send data down a stream, typically + one which has been generated by HTStreamStack. It is currently called by + HTParseMem + + */ + extern int HTMemCopy(HTChunk *chunk, + HTStream *sink); +#endif + +/* + +HTCopyNoCR: Copy a socket to a stream, stripping CR characters. + + It is slower than HTCopy . + + */ + + extern void HTCopyNoCR(HTParentAnchor *anchor, + int file_number, + HTStream *sink); + +/* + +Clear input buffer and set file number + + This routine and the one below provide simple character input from sockets. + (They are left over from the older architecture and may not be used very + much.) The existence of a common routine and buffer saves memory space in + small implementations. + + */ + extern void HTInitInput(int file_number); + +/* + +Get next character from buffer + + */ + extern int interrupted_in_htgetcharacter; + extern int HTGetCharacter(void); + +/* + +HTParseSocket: Parse a socket given its format + + This routine is called by protocol modules to load an object. uses + HTStreamStack and the copy routines above. Returns HT_LOADED if successful, + <0 if not. + + */ + extern int HTParseSocket(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + int file_number, + HTStream *sink); + +/* + +HTParseFile: Parse a File through a file pointer + + This routine is called by protocols modules to load an object. uses + HTStreamStack and HTFileCopy. Returns HT_LOADED if successful, can also + return HT_PARTIAL_CONTENT, HT_NO_DATA, or other <0 for failure. + + */ + extern int HTParseFile(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + FILE *fp, + HTStream *sink); + +#ifdef USE_SOURCE_CACHE +/* + +HTParseMem: Parse a document in memory + + This routine is called by protocols modules to load an object. uses + HTStreamStack and HTMemCopy. Returns HT_LOADED if successful, can also + return <0 for failure. + + */ + extern int HTParseMem(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + HTChunk *chunk, + HTStream *sink); +#endif + +#ifdef USE_ZLIB +/* +HTParseGzFile: Parse a gzip'ed File through a file pointer + + This routine is called by protocols modules to load an object. uses + HTStreamStack and HTGzFileCopy. Returns HT_LOADED if successful, can also + return HT_PARTIAL_CONTENT, HT_NO_DATA, or other <0 for failure. + */ + extern int HTParseGzFile(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + gzFile gzfp, + HTStream *sink); + +/* +HTParseZzFile: Parse a deflate'd File through a file pointer + + This routine is called by protocols modules to load an object. uses + HTStreamStack and HTZzFileCopy. Returns HT_LOADED if successful, can also + return HT_PARTIAL_CONTENT, HT_NO_DATA, or other <0 for failure. + */ + extern int HTParseZzFile(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + FILE *zzfp, + HTStream *sink); + +#endif /* USE_ZLIB */ + +#ifdef USE_BZLIB +/* +HTParseBzFile: Parse a bzip2'ed File through a file pointer + + This routine is called by protocols modules to load an object. uses + HTStreamStack and HTGzFileCopy. Returns HT_LOADED if successful, can also + return HT_PARTIAL_CONTENT, HT_NO_DATA, or other <0 for failure. + */ + extern int HTParseBzFile(HTFormat format_in, + HTFormat format_out, + HTParentAnchor *anchor, + BZFILE * bzfp, + HTStream *sink); + +#endif /* USE_BZLIB */ + +/* + +HTNetToText: Convert Net ASCII to local representation + + This is a filter stream suitable for taking text from a socket and passing + it into a stream which expects text in the local C representation. It does + ASCII and newline conversion. As usual, pass its output stream to it when + creating it. + + */ + extern HTStream *HTNetToText(HTStream *sink); + +/* + +HTFormatInit: Set up default presentations and conversions + + These are defined in HTInit.c or HTSInit.c if these have been replaced. If + you don't call this routine, and you don't define any presentations, then + this routine will automatically be called the first time a conversion is + needed. However, if you explicitly add some conversions (eg using + HTLoadRules) then you may want also to explicitly call this to get the + defaults as well. + + */ + extern void HTFormatInit(void); + +/* + +Epilogue + + */ + extern BOOL HTOutputSource; /* Flag: shortcut parser */ + +#ifdef __cplusplus +} +#endif +#endif /* HTFORMAT_H */ |