diff options
| author | nobody <nobody@localhost> | 2000-08-22 20:05:30 +0800 |
|---|---|---|
| committer | nobody <nobody@localhost> | 2000-08-22 20:05:30 +0800 |
| commit | 4feb5a35394873211173950dd8a93f34fa510f95 (patch) | |
| tree | 3b4824784cd30983db4a6ae1f38db287d5815941 /libversit/README.TXT | |
| parent | 44ae37c371e25fe05e8aee145f1d9af7130a201d (diff) | |
| download | gsoc2013-evolution-EOG_0_5.tar.gz gsoc2013-evolution-EOG_0_5.tar.zst gsoc2013-evolution-EOG_0_5.zip | |
This commit was manufactured by cvs2svn to create tag 'EOG_0_5'.EOG_0_5
svn path=/tags/EOG_0_5/; revision=4929
Diffstat (limited to 'libversit/README.TXT')
| -rw-r--r-- | libversit/README.TXT | 951 |
1 files changed, 0 insertions, 951 deletions
diff --git a/libversit/README.TXT b/libversit/README.TXT deleted file mode 100644 index c8ce8b0979..0000000000 --- a/libversit/README.TXT +++ /dev/null @@ -1,951 +0,0 @@ -NOTE: If you used the earlier APIs released by Versit
-then you will want to look at the document "migrate.doc"
-included with this package. It contains a discussion of
-the differences between the old API and this one.
-
-----------------------------------------------------------------
-
-The vCard/vCalendar C interface is implemented in the set
-of files as follows:
-
-vcc.y, yacc source, and vcc.c, the yacc output you will use
-implements the core parser
-
-vobject.c implements an API that insulates the caller from
-the parser and changes in the vCard/vCalendar BNF
-
-port.h defines compilation environment dependent stuff
-
-vcc.h and vobject.h are header files for their .c counterparts
-
-vcaltmp.h and vcaltmp.c implement vCalendar "macro" functions
-which you may find useful.
-
-test.c is a standalone test driver that exercises some of
-the features of the APIs provided. Invoke test.exe on a
-VCARD/VCALENDAR input text file and you will see the pretty
-print output of the internal representation (this pretty print
-output should give you a good idea of how the internal
-representation looks like -- there is one such output in the
-following too). Also, a file with the .out suffix is generated
-to show that the internal representation can be written back
-in the original text format.
-
------------------------------------------------------------------
-
-
- VObject for VCard/VCalendar
-
-Table of Contents
-=================
-1. VObject
-2. Internal Representations of VCard/VCalendar
-3. Iterating Through VObject's Properties or Values
-4. Pretty Printing a VObject Tree
-5. Building A VObject Representation of A VCard/VCalendar
-6. Converting A VObject Representation Into Its Textual Representation
-7. Miscellaneous Notes On VObject APIs usages
-8. Brief descriptions of each APIs
-9. Additional Programming Notes.
-
-This document is mainly about the VObject and its APIs. The main
-use of a VObject is to represent a VCard or a VCalendar inside
-a program. However, its use is not limited to aforemention as it
-can represent an arbitrary information that makes up of a tree or
-forest of properties/values.
-
-1. VObject
- =======
-A VObject can have a name (id) and a list of associated properties and
-a value. Each property is itself a VObject.
-
-2. Internal Representations of VCard/VCalendar
- ===========================================
-A list of VCard or a VCalendar is represented by a list of VObjects.
-The name (id) of the VObjects in the list is either VCCardProp or
-VCCalProp. Each of these VObjects can have a list of properties.
-Since a property is represented as a VObject, each of these properties
-can have a name, a list of properties, and a value.
-
-For example, the input file "vobject.vcf":
-
-BEGIN:VCARD
-N:Alden;Roland
-FN:Roland H. Alden
-ORG:AT&T;Versit Project Office
-TITLE:Consultant
-EMAIL;WORK;PREF;INTERNET:sf!rincon!ralden@alden.attmail.com
-EMAIL;INTERNET:ralden@sfgate.com
-EMAIL;MCIMail:242-2200
-LABEL;DOM;POSTAL;PARCEL;HOME;WORK;QUOTED-PRINTABLE:Roland H. Alden=0A=
-Suite 2208=0A=
-One Pine Street=0A=
-San Francisco, CA 94111
-LABEL;POSTAL;PARCEL;HOME;WORK;QUOTED-PRINTABLE:Roland H. Alden=0A=
-Suite 2208=0A=
-One Pine Street=0A=
-San Francisco, CA 94111=0A=
-U.S.A.
-TEL;WORK;PREF;MSG:+1 415 296 9106
-TEL;WORK;FAX:+1 415 296 9016
-TEL;MSG;CELL:+1 415 608 5981
-ADR:;Suite 2208;One Pine Street;San Francisco;CA;94111;U.S.A.
-SOUND:ROW-LAND H ALL-DIN
-LOGO;GIF;BASE64:
- R0lGODdhpgBOAMQAAP///+/v797e3s7Ozr29va2trZycnIyMjHt7e2NjY1JSUkJC
- QjExMSEhIRAQEO///87v9973/73n95zW71K13jGl1nvG50Kt3iGc1gCMzq3e94zO
- 7xCU1nO952O15wAAACwAAAAApgBOAAAF/yAgjmRpnmiqrmzrvnAsz3Rt33iu73zv
- /8CgcEj8QTaeywWTyWCUno2kSK0KI5tLc8vtNi+WiHVMlj0mFK96nalsxOW4fPSw
- cNj4tQc+7xcjGh4WExJTJYUTFkp3eU0eEH6RkpOUlTARhRoWm5ydFpCWoS0QEqAu
- ARKaHRcVjV0borEoFl0cSre4Sq67FA+yvwAeTU8XHZ7HmxS6u2wVfMCVpAE3pJoW
- ylrMptDcOqSF4OHg3eQ5pInInb7lcc86mNbLzBXsZbRfUOn6ucyNHvVWJHCpQFDf
- MWwEEzLqx2YCQCqF3OnItClJNmYcJD7cSAKTuI/gtnEcOQKkyVIk6/+ds5CkFcMM
- 61LiENikwi1jBnNyuvUSjwWZOS5uIZarqNFcNl32XMMB6I06GgoJ+bZp1ZKeDl8E
- +MC1K1cBIhZ4HUu2LAsCZdOWRQDt20lxIlccSHsgrNq7Xc/ixcsWmNu34WKyYJCW
- gQjCe9XqTZy2L4pv04gg2sSKSc8OLgTcBSuWsdkVaD2TdXyiQxebFyjo1Gnx6tJm
- LuaqrdtZtNfFtruSNmF5IKujwIsmJbjwtRqNJhrcNVw79wcRAgogmE4ArIjQzj/s
- JvHAGCFDQR4UqigPK4sBe62XwO51OwADiMcqUG+iOdcFAL+hW20BfAoEexlwAnu6
- mZDAXQ1EVh//WfhxJB5gIbHgwFgOTOiVAgOuVQKAfKFg3weGwSBYFZMp4hpDGKyA
- 3lgJKECWgiMQyBVpW+0V4oJjNfhCNkR1IgWEb21QlRK9GdfFCgeOZYBsXgm4noYj
- GEBhAQHYh0J8XenoQnFGdrkUciJY6FUAK15ogozakcBhliKsyZWHDMZQ0wWC/Aim
- DB6h01KRr/lXQgFxAqDcWDACgCZpUnrVQJtjwTnWjS6MWAYqqfDnSaEkJOlVXQBo
- 2pWTMUJ53WgAuPncCR9q6VQMAYjZlXWJmknCoSUM2p4BC+SaKwG88hoZlvfFMM4f
- hQh5TXkv+RklWYtC91mopJIAKFkJlDAW/wF25ShnLbeo5gmQ+1FGkJdrKCuCi2OR
- BuwHBcwqKgABrMtVAgpem61XkLbAJ7n8uiIpvGVhO4KpH1QLbbpqLheZvQCkGoNL
- thSzSTg2UGVBBzbtaxwKsYrmgLvRAlCmWgwMAADD66rKAgR3XlGspcdkZYK8ibU7
- asgEl+XAyB8I7PCqMWiWncGGimpfAgO4ypXSPpOVLwsRCDJxRD2AoyeRRv5kApO5
- fXwzwvfOKLKtaTWtbQxccmGLTZy8xYlVSvXbhbk0M2YzrYfJJ0K8m+V9NgxpyC04
- UycI/aiuiH9Y8NftDUwWp1Wm5UABnAUKwwRsPFGBt4Oc9PZvGvNLwf8JOZt8Arpe
- eY23yDovwIDiBX74NAsPVLDJj3Hh4JEExsKcjrlKf9DsCVx3ZfLqAKBuG1s/A90C
- z2KjYHjjyPOdG1spz6BBUr+BcUxUb1nDCTa/VZD2Uv+YkLPAKJC9dNEh7628WgqI
- ybzlaA+ufxMa6bxC6ciLUQLcx5UGIAAsAkDA6wQkOxrcY39yo4cQMNWCAPTKV1R4
- wPkgaBxzOc8FtMiF1NoGoXBRJjgoPApmPsjCFlbMdzCM4TFy50IXxI2DPcHAv2rY
- gghsEIeu8CAPW6ABIPYEFkOsAeaMyIz0JfGJUExBBGRIRX0IMYovWCIT1eBELNpA
- i1vcgta8iANPCIQOghzQABl30J0tXqBla4wjFLFQxZzAUY42CIAd5OYBCuKxB2c4
- I0b28EcrQKADgmSKB9RYyDhA4BqCxIBqrtjIMTwoFeCjYSU3KZMQAAA7
-
-BEGIN:VCALENDAR
-DCREATED:19960523T100522
-PRODID:-//Alden Roland/Hand Crafted In North Carolina//NONSGML Made By Hand//EN
-VERSION:0.3
-BEGIN:VEVENT
-START:19960523T120000
-END:19960523T130000
-SUBTYPE:PHONE CALL
-SUMMARY:VERSIT PDI PR Teleconference/Interview
-DESCRIPTION:VERSIT PDI PR Teleconference/Interview With Tom Streeter and Alden Roland
-END:VEVENT
-BEGIN:VEVENT
-START:19960523T113000
-END:19960523T115500
-SUBTYPE:LUNCH
-SUMMARY:Eat in the cafeteria today
-END:VEVENT
-END:VCALENDAR
-
-END:VCARD
-
-
-will conceptually be be represented as
- vcard
- VCNameProp
- VCFamilyNameProp=Alden
- VCGivenNameProp=Roland
- VCFullNameProp=Roland H.Alden
- ....
-
-note that
- EMAIL;WORK;PREF;INTERNET:sf!rincon!ralden@alden.attmail.com
-will be represented as:
- VCEmailAddress=sf!rincon!ralden@alden.attmail.com
- VCWork
- VCPreferred
- VCInternet
-where the lower level properties are properties of the property
-VCEmailAddress.
-
-Groupings are flattened out in the VObject representation such
-that:
- a.b:blah
- a.c:blahblah
-are represented as:
- b=blah
- VCGrouping=a
- c=blahblah
- VCGrouping=a
-i.e. one can read the above as:
- the property "b" has value "blah" and property "VCGrouping"
- with the value "a".
- the property "c" has value "blahblah" and property "VCGrouping"
- with the value "a".
-likewise, multi-level groupings are flatten similarly. e.g.
- a.b.c:blah
- a.b.e:blahblah
--->
- c=blah
- VCGrouping=b
- VCGrouping=a
- e=blahblah
- VCGrouping=b
- VCGrouping=a
-which read:
- the property "c" has value "blah" and property "VCGrouping"
- with the value "b" which has property "VCGrouping"
- with value "a".
- the property "e" has value "blahblah" and property "VCGrouping"
- with the value "b" which has property "VCGrouping"
- with value "a".
-
-3. Iterating Through VObject's Properties or Values
- ================================================
-The following is a skeletal form of iterating through
-all properties of a vobject, o:
-
- // assume the object of interest, o, is of type VObject
- VObjectIterator i;
- initPropIterator(&i,o);
- while (moreIteration(&i)) {
- VObject *each = nextVObject(&i);
- // ... do something with "each" property
- }
-
-Use the API vObjectName() to access a VObject's name.
-Use the API vObjectValueType() to determine if a VObject has
- a value. For VCard/VCalendar application, you
- should not need this function as practically
- all values are either of type VCVT_USTRINGZ or
- VCVT_RAW (i.e set by setVObjectUStringZValue and
- setVObjectAnyValue APIs respectively), and the
- value returned by calls to vObjectUStringZValue
- and vObjectAnyValue are 0 if a VObject has no
- value. (There is a minor exception where VObject with
- VCDataSizeProp has value that is set by
- setVObjectLongValue).
-Use the APIs vObject???Value() to access a VObject's value.
- where ??? is the expected type.
-Use the APIs setvObject???Value() to set or modify a VObject's value.
- where ??? is the expected type.
-Use the API isAPropertyOf() to query if a name match the name of
- a property of a VObject. Since isAPropertyOf() return
- the matching property, we can use that to retrieve
- a property and subsequently the value of the property.
-
-4. Pretty Printing a VObject Tree
- ==============================
-VObject tree can be pretty printed with the printVObject() function.
-The output of pretty printing a VObject representation of the input
-test file "vobject.vcf" is shown below. Note that the indentation
-indicates the tree hirerarchy where the immediate children nodes
-of a parent node is all at the same indentation level and the
-immediate children nodes are the immediate properties of the
-associated parent nodes. In the following, {N,FN,ORG,TITLE,...}
-are immediate properties of VCARD. {F and G} are properties of N
-with value {"Alden" and "Roland"} respectively; FN has no property
-but has the value "Roland H. Alden"; EMAIL has value and
-the properties WORK, PREF, and INTERNET.
-
-
-VCARD
- N
- F="Alden"
- G="Roland"
- FN="Roland H. Alden"
- ORG
- ORGNAME="AT&T"
- OUN="Versit Project Office"
- TITLE="Consultant"
- EMAIL="sf!rincon!ralden@alden.attmail.com"
- WORK
- PREF
- INTERNET
- EMAIL="ralden@sfgate.com"
- INTERNET
- EMAIL="242-2200"
- MCIMail
- LABEL="Roland H. Alden
- Suite 2208
- One Pine Street
- San Francisco, CA 94111"
- DOM
- POSTAL
- PARCEL
- HOME
- WORK
- QP
- LABEL="Roland H. Alden
- Suite 2208
- One Pine Street
- San Francisco, CA 94111
- U.S.A."
- POSTAL
- PARCEL
- HOME
- WORK
- QP
- TEL="+1 415 296 9106"
- WORK
- PREF
- MSG
- TEL="+1 415 296 9016"
- WORK
- FAX
- TEL="+1 415 608 5981"
- MSG
- CELL
- ADR
- EXT ADD="Suite 2208"
- STREET="One Pine Street"
- L="San Francisco"
- R="CA"
- PC="94111"
- C="U.S.A."
- SOUND="ROW-LAND H ALL-DIN"
- LOGO=[raw data]
- GIF
- BASE64
- DataSize=1482
-VCALENDAR
- DCREATED="19960523T100522"
- PRODID="-//Alden Roland/Hand Crafted In North Carolina//NONSGML Made By Hand//EN"
- VERSION="0.3"
- VEVENT
- START="19960523T120000"
- END="19960523T130000"
- SUBTYPE="PHONE CALL"
- SUMMARY="VERSIT PDI PR Teleconference/Interview"
- DESCRIPTION="VERSIT PDI PR Teleconference/Interview With Tom Streeter and Alden Roland"
- VEVENT
- START="19960523T113000"
- END="19960523T115500"
- SUBTYPE="LUNCH"
- SUMMARY="Eat in the cafeteria today"
-
-5. Building A VObject Representation of A VCard/VCalendar
- ======================================================
-The parser in vcc.y converts an input file with one or more
-VCard/VCalendar that is in their textual representation
-into their corresponding VObject representation.
-
-VObject representation of a VCard/VCalendar can also be built
-directly with calls to the VObject building APIs. e.g.
-
- VObject *prop;
- VObject *vcard = newVObject(VCCardProp);
- prop = addProp(vcard,VCNameProp);
- addPropValue(prop,VCFamilyNameProp,"Alden");
- addPropValue(prop,VCGivenNameProp,"Roland");
- addPropValue(vcard,VCFullNameProp,"Roland H. Alden");
- ....
-
-6. Converting A VObject Representation Into Its Textual Representation
- ===================================================================
-The VObject representation can be converted back to its textual
-representation via the call to writeVObject() or writeMemVObject()
-API. e.g.
- a. to write to a file:
- // assume vcard is of type VObject
- FILE *fp = fopen("alden.vcf","w");
- writeVObject(fp,vcard);
- a. to write to memory, and let the API allocate the required memory.
- char* clipboard = writeVObject(0,0,vcard);
- ... do something to clipboard
- free(clipboard);
- b. to write to a user allocated buffer:
- char clipboard[16384];
- int len = 16384;
- char *buf = writeVObject(clipboard,&len,vcard);
- ... buf will be equal to clipboard if the write
- is successful otherwise 0.
-
-In the case of writing to memory, the memory buffer can be either
-allocated by the API or the user. If the user allocate the
-memory for the buffer, then the length of the buffer needs to be
-communicated to the API via a variable. The variable passed as
-the length argument will be overwritten with the actual size
-of the text output. A 0 return value from writeMemVObject()
-indicates an error which could be caused by overflowing the
-size of the buffer or lack of heap memory.
-
-7. Miscellaneous Notes On VObject APIs usages
- ==========================================
-a. vcc.h -- contains basic interfaces to the parser:
- VObject* Parse_MIME(const char *input, unsigned long len);
- VObject* Parse_MIME_FromFile(FILE *file);
- -- both of this return a null-terminated list of
- VObject that is either a VCARD or VCALENDAR.
- To iterate through this list, do
- VObject *t, *v;
- v = Parse_Mime_FromFile(fp);
- while (v) {
- // ... do something to v.
- t = v;
- v = nextVObjectInList(v);
- cleanVObject(t);
- }
- note that call to cleanVObject will release
- resource used to represent the VObject.
-
-b. vobject.h -- contains basic interfaces to the VObject APIs.
- see the header for more details.
- The structure of VObject is purposely (hiddened) not exposed
- to the user. Every access has to be done via
- the APIs. This way, if we need to change the
- structure or implementation, the client need not
- recompile as long as the interfaces remain the
- same.
-
-c. values of a property is determined by the property definition
- itself. The vobject APIs does not attempt to enforce
- any of such definition. It is the consumer responsibility
- to know what value is expected from a property. e.g
- most properties have unicode string value, so to access
- the value of these type of properties, you will use
- the vObjectUStringZValue() to read the value and
- setVObjectUStringZValue() to set or modify the value.
- Refer to the VCard and VCalendar specifications for
- the definition of each property.
-
-d. properties name (id) are case incensitive.
-
-8. Brief descriptions of each APIs
- ===============================
- * the predefined properties' names (id) are listed under vobject.h
- each is of the form VC*Prop. e.g.
- #define VC7bitProp "7BIT"
- #define VCAAlarmProp "AALARM"
- ....
-
- * consumer of a VObject can only define pointers to VObject.
-
- * a variable of type VObjectIterator, say "i", can be used to iterate
- through a VObject's properties, say "o". The APIs related to
- VObjectIterator are:
- void initPropIterator(VObjectIterator *i, VObject *o);
- -- e.g. usage
- initPropIterator(&i,o);
- int moreIteration(VObjectIterator *i);
- -- e.g. usage
- while (moreIteration(&i)) { ... }
- VObject* nextVObject(VObjectIterator *i);
- -- e.g. usage
- while (moreIteration(&i)) {
- VObject *each = nextVObject(&i);
- }
-
- * VObject can be chained together to form a list. e.g. of such
- use is in the parser where the return value of the parser is
- a link list of VObject. A link list of VObject can be
- built by:
- void addList(VObject **o, VObject *p);
- and iterated by
- VObject* nextVObjectInList(VObject *o);
- -- next VObjectInList return 0 if the list
- is exhausted.
-
- * the following APIs are mainly used to construct a VObject tree:
- VObject* newVObject(const char *id);
- -- used extensively internally by VObject APIs but when
- used externally, its use is mainly limited to the
- construction of top level object (e.g. an object
- with VCCardProp or VCCalendarProp id).
-
- void deleteVObject(VObject *p);
- -- to deallocate single VObject, for most user, use
- cleanVObject(VObject *o) instead for freeing all
- resources associated with the VObject.
-
- char* dupStr(const char *s, unsigned int size);
- -- duplicate a string s. If size is 0, the string is
- assume to be a null-terminated.
-
- void deleteStr(const char *p);
- -- used to deallocate a string allocated by dupStr();
-
- void setVObjectName(VObject *o, const char* id);
- -- set the id of VObject o. This function is not
- normally used by the user. The setting of id
- is normally done as part of other APIs (e.g.
- addProp()).
-
- void setVObjectStringZValue(VObject *o, const char *s);
- -- set a string value of a VObject.
-
- void setVObjectUStringZValue(VObject *o, const wchar_t *s);
- -- set a Unicode string value of a VObject.
-
- void setVObjectIntegerValue(VObject *o, unsigned int i);
- -- set an integer value of a VObject.
-
- void setVObjectLongValue(VObject *o, unsigned long l);
- -- set an long integer value of a VObject.
-
- void setVObjectAnyValue(VObject *o, void *t);
- -- set any value of a VObject. The value type is
- unspecified.
-
- VObject* setValueWithSize(VObject *prop, void *val, unsigned int size);
- -- set a raw data (stream of bytes) value of a VObject
- whose size is size. The internal VObject representation
- is
- this object = val
- VCDataSizeProp=size
- i.e. the value val will be attached to the VObject prop
- and a property of VCDataSize whose value is size
- is also added to the object.
-
- void setVObjectVObjectValue(VObject *o, VObject *p);
- -- set a VObject as the value of another VObject.
-
- const char* vObjectName(VObject *o);
- -- retrieve the VObject's Name (i.e. id).
-
- const char* vObjectStringZValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- null-terminated string.
-
- const wchar_t* vObjectUStringZValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- null-terminated unicode string.
-
- unsigned int vObjectIntegerValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- integer.
-
- unsigned long vObjectLongValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- long integer.
-
- void* vObjectAnyValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- any value.
-
- VObject* vObjectVObjectValue(VObject *o);
- -- retrieve the VObject's value interpreted as
- a VObject.
-
- VObject* addVObjectProp(VObject *o, VObject *p);
- -- add a VObject p as a property of VObject o.
- (not normally used externally for building a
- VObject).
-
- VObject* addProp(VObject *o, const char *id);
- -- add a property whose name is id to VObject o.
-
- VObject* addPropValue(VObject *o, const char *id, const char *v);
- -- add a property whose name is id and whose value
- is a null-terminated string to VObject o.
-
- VObject* addPropSizedValue(VObject *o, const char *id,
- const char *v, unsigned int size);
- -- add a property whose name is id and whose value
- is a stream of bytes of size size, to VObject o.
-
- VObject* addGroup(VObject *o, const char *g);
- -- add a group g to VObject o.
- e.g. if g is a.b.c, you will have
- o
- c
- VCGroupingProp=b
- VCGroupingProp=a
- and the object c is returned.
-
- VObject* isAPropertyOf(VObject *o, const char *id);
- -- query if a property by the name id is in o and
- return the VObject that represent that property.
-
- void printVObject(VObject *o);
- -- pretty print VObject o to stdout (for debugging use).
-
- void writeVObject(FILE *fp, VObject *o);
- -- convert VObject o to its textual representation and
- write it to file.
-
- char* writeMemVObject(char *s, int *len, VObject *o);
- -- convert VObject o to its textual representation and
- write it to memory. If s is 0, then memory required
- to hold the textual representation will be allocated
- by this API. If a variable len is passed, len will
- be overwriten with the byte size of the textual
- representation. If s is non-zero, then s has to
- be a user allocated buffer whose size has be passed
- in len as a variable. Memory allocated by the API
- has to be freed with call to free. The return value
- of this API is either the user supplied buffer,
- the memory allocated by the API, or 0 (in case of
- failure).
-
- void cleanStrTbl();
- -- this function has to be called when all
- VObject has been destroyed.
-
- void cleanVObject(VObject *o);
- -- release all resources used by VObject o.
-
- wchar_t* fakeUnicode(const char *ps, int *bytes);
- -- convert char* to wchar_t*.
-
- extern int uStrLen(const wchar_t *u);
- -- length of unicode u.
-
- char *fakeCString(const wchar_t *u);
- -- convert wchar_t to CString (blindly assumes that
- this could be done).
-
-9. Additional Programming Notes
- ============================
-In the following notes, please refers to the listing
-of Example.vcf and its VObject Representation
-(shown at the end of this section).
-
-* Handling the Return Value of the VCard/VCalendar Parser
- The example input text file contains two root VObjects
- (a VCalendar and a VCard). The output of the VCard/VCalendar
- parser is a null-terminated list of VObjects. For this
- particular input file, the list will have two VObjects.
- The following shows a template for iterating through the
- output of the Parser:
-
- VObject *t, *v;
- v = Parse_Mime_fromFileName("example.vcf");
- while (v) {
- // currently, v will either be a VCard or a VCalendar
- // do whatever your application need to do to
- // v here ...
- t = v;
- v = nextVObjectInList(v);
- cleanVObject(t);
- }
-
-* Iterating Through a VCard/VCalendar VObject
- From the VObject APIs point of view, a VCard VObject
- is the same as a VCalendar VObject. However, the application
- needs to know what are in a VCard or a VCalendar.
- For example, A VCalendar VObject can have VCDCreatedProp,
- a VCGEOLocationProp, etc, and one or more VCEventProp and
- or VCTodoProp. The VCEventProp and VCTodoProp can have
- many properties of their own, which in turn could have
- more properties (e.g. VCDAlarmProp can be a VCEventProp
- VObject's property, and VCRunTimeProp can be a
- VCDAlarmProp VObject's property. Because a VObject tree
- can be arbitrarily complex, in general, to process all
- properties and values of a VObject tree, a recursive walk
- is desirable. An example recursive VObject tree walk
- can be found in the vobject.c source lines for printVObject*
- and writeVObject* APIs. Depending on what the application need
- to do with a VCard or a VCalendar, a recursive walk
- of the VObject tree may or may not be desirable. An example
- template of a non-recursive walk is shown below:
-
- void processVCardVCalendar(char *inputFile)
- {
- VObject *t, *v;
- v = Parse_Mime_fromFileName(inputFile);
- while (v) {
- char *n = vObjectName(v);
- if (strcmp(n,VCCardProp) == 0) {
- do_VCard(v);
- }
- else if (strcmp(n,VCCalendarProp) == 0) {
- do_VCalendar(v);
- }
- else {
- // don't know how to handle anything else!
- }
- t = v;
- v = nextVObjectInList(v);
- cleanVObject(t);
- }
- }
-
- void do_VCard(VObject *vcard)
- {
- VObjectIterator t;
- initPropIterator(&t,vcard);
- while (moreIteration(&t)) {
- VObject *eachProp = nextVObject(&t);
- // The primarly purpose of this example is to
- // show how to iterate through a VCard VObject,
- // it is not meant to be efficient at all.
- char *n = vObjectName(eachProp);
- if (strcmp(n,VCNameProp)==0) {
- do_name(eachProp);
- }
- else if (strcmp(n,VCEmailProp)==0) {
- do_email(eachProp);
- }
- else if (strcmp(n,VCLabelProp)==0) {
- do_label(eachProp);
- }
- else if ....
- }
- }
-
- void do_VCalendar(VObject *vcal)
- {
- VObjectIterator t;
- initPropIterator(&t,vcard);
- while (moreIteration(&t)) {
- VObject *eachProp = nextVObject(&t);
- // The primarly purpose of this example is to
- // show how to iterate through a VCalendar VObject,
- // it is not meant to be efficient at all.
- char *n = vObjectName(eachProp);
- if (strcmp(n,VCDCreatedProp)==0) {
- do_DCreated(eachProp);
- }
- else if (strcmp(n,VCVersionProp)==0) {
- do_Version(eachProp);
- }
- else if (strcmp(n,VCTodoProp)==0) {
- do_Todo(eachProp);
- }
- else if (strcmp(n,VCEventProp)==0) {
- do_Event(eachProp);
- }
- else if ....
- }
- }
-
- void do_Todo(VObject *vtodo) { ... }
-
- void do_Event(VObject *vevent) { ... }
-
- ...
-
-* Property's Values and Properties
- The VObject APIs do not attempt to check for the
- correctness of the values of a property. Nor do they
- will prevent the user from attaching a non-VCard/VCalendar
- standard property to a VCard/VCalendar property. Take
- the example of line [11] of the example, "O.K" is not
- a valid value of VCStatusProp. It is up to the application
- to accept or reject the value of a property.
-
-* Output of printVObject
- PrintVObject pretty prints a VObject tree in human
- readable form. See the listing at the end of the file
- for an example output of printVObject on the example
- input file "Example.vcf".
-
- Note that binary data are not shown in the output of
- printVObject. Instead, a note is made ([raw data]) to
- indicate that there exists such a binary data.
-
-* Note on Binary Data
- When the value of a property is a binary data, it is only
- useful to know the size of the binary data.
-
- In the case of the VCard/VCalendar parser, it chooses
- to represent the size information as a separate property
- called VCDataSizeProp whose value is the size of the binary
- data. The APIs sequence to construct the VObject subtree
- of line [44] of Example.vcf is
-
- // VObject *vcard;
- VObject *p1 = addProp(vcard,VCLogoProp);
- (void) addProp(p1,VCGIFProp);
- (void) addProp(p1,VCBASE64Prop);
- VObject *p2 = addProp(p1,VCDataSizeProp);
- (void) setVObjectLongValue(p2,1482);
- setVObjectAnyValue(vcard,...pointer to binary data);
-
- Note the presence of VCBase64Prop will cause the
- writeVObject API to output the binary data as BASE64 text.
- For VCard/VCalendar application, having the VCBase64Prop
- property is pratically always neccessary for property with
- binary data as its value.
-
-* Note on Quoted-Printable String
- String value with embedded newline are written out as
- quoted-prinatable string. It is therefore important
- to mark a property with a string value that has
- one or more embedded newlines, with the VCQutedPrintableProp
- property. e.g.
-
- // VObject *root;
- char *msg="To be\nor\nnot to be";
- VObject *p = addPropValue(root,VCDescriptionProp,msg);
- // the following is how you mark a property with
- // a property. In this case, the marker is
- // VCQuotedPrintableProp
- addProp(p,VCQuotedPrintableProp);
-
-* Note on Unicode
- Although, the current parser takes ASCII text file only,
- string values are all stored as Unicode in the VObject tree.
- For now, when using the VObject APIs to construct a
- VObject tree, one should always convert ASCII string value
- to a Unicode string value:
-
- // VObject *root;
- VObject *p = addProp(root,VCSomeProp);
- setVObjectUStringZValue(p,fakeUnicode(someASCIIStringZvalue));
-
- An API is provided to simplify the above process:
-
- addPropValue(root,VCSomeProp,someASCIIStringZValue);
-
- Note that someASCIISTringZValue is automatically converted to
- Unicode by addPropValue API, where as, the former code
- sequence do an explicit call to fakeUnicode.
-
- To read back the value, one should use the vObjectUStringZValue
- API not vObjectStringZValue API. The value returned by the
- vObjectUStringZValue API is a Unicode string. If the application
- do not know how to handle Unicode string, it can use the
- fakeCString API to convert it back to ASCII string (as long
- as the conversion is meaningful).
-
- Note that fakeCString return a heap allocated memory. It is
- important to call deleteStr on fakeCString return value if
- it is not longer required (or there will be memory leak).
-
- NOTE: Unfortunately, at the point when this document is written,
- there is still no consensus on how Unicode is to be handled
- in the textual representation of VCard/VCalendar. So, there
- is no version of writeVObject and the parser to output and
- input Unicode textual representation of VCard/VCalendar.
-
-
-Example.vcf
------------
-line
-number Input Text (example.vcf)
------- ----------
-1 BEGIN:VCALENDAR
-2 DCREATED:19961102T100522
-3 GEO:0,0
-4 VERSION:1.0
-5 BEGIN:VEVENT
-6 DTSTART:19961103T000000
-7 DTEND:20000101T000000
-8 DESCRIPTION;QUOTED-PRINTABLE:To be =0A=
-9 or =0A=
-10 not to be
-11 STATUS:O.K.
-12 X-ACTION:No action required
-13 DALARM:19961103T114500;5;3;Enjoy
-14 MALARM:19970101T120000;;;johny@nowhere.com;Call Mom.
-15 END:VEVENT
-16
-17 BEGIN:VTODO
-18 DUE:19960614T0173000
-19 DESCRIPTION:Relex.
-20 END:VTODO
-21
-22 END:VCALENDAR
-23
-24 BEGIN:VCARD
-25 N:Alden;Roland
-26 FN:Roland H. Alden
-27 ORG:AT&T;Versit Project Office
-28 TITLE:Consultant
-29 EMAIL;WORK;PREF;INTERNET:ralden@ralden.com
-30 LABEL;DOM;POSTAL;PARCEL;HOME;WORK;QUOTED-PRINTABLE:Roland H. Alden=0A=
-31 Suite 2208=0A=
-32 One Pine Street=0A=
-33 San Francisco, CA 94111
-34 LABEL;POSTAL;PARCEL;HOME;WORK;QUOTED-PRINTABLE:Roland H. Alden=0A=
-35 Suite 2208=0A=
-36 One Pine Street=0A=
-37 San Francisco, CA 94111=0A=
-38 U.S.A.
-39 TEL;WORK;PREF;MSG:+1 415 296 9106
-40 TEL;WORK;FAX:+1 415 296 9016
-41 TEL;MSG;CELL:+1 415 608 5981
-42 ADR:;Suite 2208;One Pine Street;San Francisco;CA;94111;U.S.A.
-43 SOUND:ROW-LAND H ALL-DIN
-44 LOGO;GIF;BASE64:
-45 R0lGODdhpgBOAMQAAP///+/v797e3s7Ozr29va2trZycnIyMjHt7e2NjY1JSUkJC
- ... 30 lines of BASE64 data not shown here.
-76 END:VCARD
-
-
-VObject Representation of Example.vcf:
--------------------------------------
-line
-in
-text
-file VObject Tree as Printed by printVObject API
----- -------------------------------------------
-1 VCALENDAR
-2 DCREATED="19961102T100522"
-3 GEO="0,0"
-4 VERSION="1.0"
-5 VEVENT
-6 DTSTART="19961103T000000"
-7 DTEND="20000101T000000"
-8 DESCRIPTION="To be
-9 or
-10 not to be"
-8 QUOTED-PRINTABLE
-11 STATUS="O.K."
-12 X-ACTION="No action required"
-13 DALARM
-13 RUNTIME="19961103T114500"
-13 SNOOZETIME="5"
-13 REPEATCOUNT="3"
-13 DISPLAYSTRING="Enjoy"
-14 MALARM
-14 RUNTIME="19970101T120000"
-14 EMAIL="johny@nowhere.com"
-14 NOTE="Call Mom"
-17 VTODO
-18 DUE="19960614T0173000"
-19 DESCRIPTION="Relex."
-24 VCARD
-25 N
-25 F="Alden"
-25 G="Roland"
-26 FN="Roland H. Alden"
-27 ORG
-27 ORGNAME="AT&T"
-27 OUN="Versit Project Office"
-28 TITLE="Consultant"
-29 EMAIL="ralden@alden.com"
-29 WORK
-29 PREF
-29 INTERNET
-30 LABEL="Roland H. Alden
-31 Suite 2208
-32 One Pine Street
-33 San Francisco, CA 94111"
-30 DOM
-30 POSTAL
-30 PARCEL
-30 HOME
-30 WORK
-30 QUOTED-PRINTABLE
-34 LABEL="Roland H. Alden
-35 Suite 2208
-36 One Pine Street
-37 San Francisco, CA 94111
-38 U.S.A."
-34 POSTAL
-34 PARCEL
-34 HOME
-34 WORK
-34 QUOTED-PRINTABLE
-39 TEL="+1 415 296 9106"
-39 WORK
-39 PREF
-39 MSG
-40 TEL="+1 415 296 9016"
-40 WORK
-40 FAX
-41 TEL="+1 415 608 5981"
-41 MSG
-41 CELL
-42 ADR
-42 EXT ADD="Suite 2208"
-42 STREET="One Pine Street"
-42 L="San Francisco"
-42 R="CA"
-42 PC="94111"
-42 C="U.S.A."
-43 SOUND="ROW-LAND H ALL-DIN"
-44 LOGO=[raw data]
-44 GIF
-44 BASE64
-44 DATASIZE=1482
-
|