From: Peter Verthez Date: Mon, 31 Dec 2001 15:55:40 +0000 (+0000) Subject: More documentation. X-Git-Url: https://git.dlugolecki.net.pl/?a=commitdiff_plain;h=a6f453d612fe285d2585b689e3e4d675de455510;p=gedcom-parse.git More documentation. --- diff --git a/doc/index.html b/doc/index.html index 09858f3..6fa2fde 100644 --- a/doc/index.html +++ b/doc/index.html @@ -2,35 +2,36 @@ The GEDCOM parser library - + - +

The GEDCOM parser library

- This is the documentation for the GEDCOM parser library, release @VERSION@.
+ This is the documentation for the GEDCOM parser library, release @VERSION@.
+
+ The GEDCOM parser library is a C library that provides an API to applications + to parse and process arbitrary genealogy files in the standard gedcom format. + It supports release 5.5 + of the GEDCOM standard.

- The GEDCOM parser library is a C library that provides an API to applications - to parse and process arbitrary genealogy files in the standard gedcom format. - It supports release 5.5 - of the GEDCOM standard.
-
- The rest of the documentation is divided into three parts:
- + The rest of the documentation is divided into three parts:
+

Usage: This is the main entry point for +
Usage: This is the main entry point for application developers, using the library
Development: This describes some internals +
Development: This describes some internals of the library
Links: A collection of useful links, also +
Links: A collection of useful links, also referenced in the rest of the documentation
-

- -

$Id$
- $Name$
-
- + +

$Id: index.html,v 1.1 2001/12/30 22:45:43 verthezp +Exp $
+ $Name$
+
+ diff --git a/doc/interface.html b/doc/interface.html new file mode 100644 index 0000000..46ccd08 --- /dev/null +++ b/doc/interface.html @@ -0,0 +1,1880 @@ + + + + Libgedcom interface details + + + + + +

Libgedcom interface details

+
+ +

Index

+ +

Record identifiers
Element identifiers
Gedcom_val types

struct date_value
struct date
+

+
+ +

Record identifiers

+ The following table describes the identifiers to be used in the record callbacks. + The last column gives the Gedcom_val + type of the xref argument in the header start callback.
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

Record +	Meaning +	Possible + `xref` types +
`REC_HEAD` +	The header of the GEDCOM file +	`NULL` +
`REC_FAM` +	A record describing a family +	`STRING` +
`REC_INDI` +	A record describing an individual +	`STRING` +
`REC_OBJE` +	A record describing a multimedia object +	`STRING` +
`REC_NOTE` +	A record describing a note +	`STRING` +
`REC_REPO` +	A record describing a source repository +	`STRING` +
`REC_SOUR` +	A record describing a source +	`STRING` +
`REC_SUBN` +	A record describing the submission +	`STRING` +
`REC_SUBM` +	A record describing the submitter +	`STRING` +
`REC_USER` +	An application-specific record (the `tag` + in the start callback contains the actually used tag). +	`NULL` + `STRING` +

+ +

Element identifiers

+The following table describes the identifiers to be used in the element callbacks. + The last column gives the


+Gedcom_val

type of the val argument in the element +start callback. (TO BE COMPLETED)
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

Element +	Possible +tags + +	Used within +	Possible + `val` types + +
`ELT_HEAD_SOUR` +	`SOUR` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_SOUR_VERS` +	`VERS` +	`ELT_HEAD_SOUR` +	`STRING` +
`ELT_HEAD_SOUR_NAME` +	`NAME` +	`ELT_HEAD_SOUR` +	`STRING` +
`ELT_HEAD_SOUR_CORP` +	`CORP` +	`ELT_HEAD_SOUR` +	`STRING` +
`ELT_HEAD_SOUR_DATA` +	`DATA` +	`ELT_HEAD_SOUR` +	`STRING` +
`ELT_HEAD_SOUR_DATA_DATE` +	`DATE` +	`ELT_HEAD_SOUR_DATA` +	`DATE` +
`ELT_HEAD_SOUR_DATA_COPR` +	`COPR` +	`ELT_HEAD_SOUR_DATA` +	`STRING` +
`ELT_HEAD_DEST` +	`DEST` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_DATE` +	`DATE` +	`REC_HEAD` +	`DATE` +
`ELT_HEAD_DATE_TIME` +	`TIME` +	`ELT_HEAD_DATE` +	`STRING` +
`ELT_HEAD_SUBM` +	`SUBM` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_SUBN` +	`SUBN` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_FILE` +	`FILE` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_COPR` +	`COPR` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_GEDC` +	`GEDC` +	`REC_HEAD` +	`NULL` +
`ELT_HEAD_GEDC_VERS` +	`VERS` +	`ELT_HEAD_GEDC` +	`STRING` +
`ELT_HEAD_GEDC_FORM` +	`FORM` +	`ELT_HEAD_GEDC` +	`STRING` +
`ELT_HEAD_CHAR` +	`CHAR` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_CHAR_VERS` +	`VERS` +	`ELT_HEAD_CHAR` +	`STRING` +
`ELT_HEAD_LANG` +	`LANG` +	`REC_HEAD` +	`STRING` +
`ELT_HEAD_PLAC` +	`PLAC` +	`REC_HEAD` +	`NULL` +
`ELT_HEAD_PLAC_FORM` +	`FORM` +	`ELT_HEAD_PLAC` +	`STRING` +
`ELT_HEAD_NOTE` +	`NOTE` +	`REC_HEAD` +	`STRING` +
`ELT_FAM_HUSB` +	`HUSB` +	`REC_FAM` +	`STRING` +
`ELT_FAM_WIFE` +	`WIFE` +	`REC_FAM` +	`STRING` +
`ELT_FAM_CHIL` +	`CHIL` +	`REC_FAM` +	`STRING` +
`ELT_FAM_NCHI` +	`NCHI` +	`REC_FAM` +	`STRING` +
`ELT_FAM_SUBM` +	`SUBM` +	`REC_FAM` +	`STRING` +
`ELT_INDI_RESN` +	`RESN` +	`REC_INDI` +	`STRING` +
`ELT_INDI_SEX` +	`SEX` +	`REC_INDI` +	`STRING` +
`ELT_INDI_SUBM` +	`SUBM` +	`REC_INDI` +	`STRING` +
`ELT_INDI_ALIA` +	`ALIA` +	`REC_INDI` +	`STRING` +
`ELT_INDI_ANCI` +	`ANCI` +	+	`STRING` +
`ELT_INDI_DESI` +	`DESI` +	+	`STRING` +
`ELT_INDI_RFN` +	`RFN` +	+	`STRING` +
`ELT_INDI_AFN` +	`AFN` +	+	`STRING` +
`ELT_OBJE_FORM` +	`FORM` +	+	`STRING` +
`ELT_OBJE_TITL` +	`TITL` +	+	`STRING` +
`ELT_OBJE_BLOB` +	`BLOB` +	+	`NULL` +
`ELT_OBJE_BLOB_CONT` +	`CONT` +	+	`STRING` +
`ELT_OBJE_OBJE` +	`OBJE` +	+	`STRING` +
`ELT_REPO_NAME` +	`NAME` +	+	`STRING` +
`ELT_SOUR_DATA` +	`DATA` +	+	`NULL` +
`ELT_SOUR_DATA_EVEN` +	`EVEN` +	+	`STRING` +
`ELT_SOUR_DATA_EVEN_DATE` +	`DATE` +	+	`DATE` +
`ELT_SOUR_DATA_EVEN_PLAC` +	`PLAC` +	+	`STRING` +
`ELT_SOUR_DATA_AGNC` +	`AGNC` +	+	`STRING` +
`ELT_SOUR_AUTH` +	`AUTH` +	+	`STRING` +
`ELT_SOUR_TITL` +	`TITL` +	+	`STRING` +
`ELT_SOUR_ABBR` +	`ABBR` +	+	`STRING` +
`ELT_SOUR_PUBL` +	`PUBL` +	+	`STRING` +
`ELT_SOUR_TEXT` +	`TEXT` +	+	`STRING` +
`ELT_SUBN_SUBM` +	`SUBM` +	+	`STRING` +
`ELT_SUBN_FAMF` +	`FAMF` +	+	`STRING` +
`ELT_SUBN_TEMP` +	`TEMP` +	+	`STRING` +
`ELT_SUBN_ANCE` +	`ANCE` +	+	`STRING` +
`ELT_SUBN_DESC` +	`DESC` +	+	`STRING` +
`ELT_SUBN_ORDI` +	`ORDI` +	+	`STRING` +
`ELT_SUBN_RIN` +	`RIN` +	+	`STRING` +
`ELT_SUBM_NAME` +	`NAME` +	+	`STRING` +
`ELT_SUBM_LANG` +	`LANG` +	+	`STRING` +
`ELT_SUBM_RFN` +	`RFN` +	+	`STRING` +
`ELT_SUBM_RIN` +	`RIN` +	+	`STRING` +
`ELT_SUB_ADDR` +	`ADDR` +	+	`STRING` +
`ELT_SUB_ADDR_CONT` +	`CONT` +	+	`STRING` +
`ELT_SUB_ADDR_ADR1` +	`ADR1` +	+	`STRING` +
`ELT_SUB_ADDR_ADR2` +	`ADR2` +	+	`STRING` +
`ELT_SUB_ADDR_CITY` +	`CITY` +	+	`STRING` +
`ELT_SUB_ADDR_STAE` +	`STAE` +	+	`STRING` +
`ELT_SUB_ADDR_POST` +	`POST` +	+	`STRING` +
`ELT_SUB_ADDR_CTRY` +	`CTRY` +	+	`STRING` +
`ELT_SUB_PHON` +	`PHON` +	+	`STRING` +
`ELT_SUB_ASSO` +	`ASSO` +	+	`STRING` +
`ELT_SUB_ASSO_TYPE` +	`TYPE` +	+	`STRING` +
`ELT_SUB_ASSO_RELA` +	`RELA` +	+	`STRING` +
`ELT_SUB_CHAN` +	`CHAN` +	+	`NULL` +
`ELT_SUB_CHAN_DATE` +	`DATE` +	+	`DATE` +
`ELT_SUB_CHAN_TIME` +	`TIME` +	+	`STRING` +
`ELT_SUB_FAMC` +	`FAMC` +	+	`STRING` +
`ELT_SUB_FAMC_PEDI` +	`PEDI` +	+	`STRING` +
`ELT_SUB_CONT` +	`CONT` +	+	`STRING` +
`ELT_SUB_CONC` +	`CONC` +	+	`STRING` +
`ELT_SUB_EVT_TYPE` +	`TYPE` +	+	`STRING` +
`ELT_SUB_EVT_DATE` +	`DATE` +	+	`DATE` +
`ELT_SUB_EVT_AGE` +	`AGE` +	+	`STRING` +
`ELT_SUB_EVT_AGNC` +	`AGNC` +	+	`STRING` +
`ELT_SUB_EVT_CAUS` +	`CAUS` +	+	`STRING` +
`ELT_SUB_FAM_EVT` +	`ANUL, CENS, DIV, +DIVF, ENGA, MARR, +MARB, MARC, MARL, +MARS` +	+	`NULL +STRING` +
`ELT_SUB_FAM_EVT_HUSB` +	`HUSB` +	+	`NULL` +
`ELT_SUB_FAM_EVT_WIFE` +	`WIFE` +	+	`NULL` +
`ELT_SUB_FAM_EVT_AGE` +	`AGE` +	+	`STRING` +
`ELT_SUB_FAM_EVT_EVEN` +	`EVEN` +	+	`NULL` +
`ELT_SUB_IDENT_REFN` +	`REFN` +	+	`STRING` +
`ELT_SUB_IDENT_REFN_TYPE` +	`TYPE` +	+	`STRING` +
`ELT_SUB_IDENT_RIN` +	`RIN` +	+	`STRING` +
`ELT_SUB_INDIV_ATTR` +	`CAST, DSCR, EDUC, +IDNO, NATI, NCHR, +NMR, OCCU, PROP, +RELI, SSN, TITL` +	+	`STRING` +
`ELT_SUB_INDIV_RESI` +	`RESI` +	+	`NULL` +
`ELT_SUB_INDIV_BIRT` +	`BIRT, CHR` +	+	`NULL +STRING` +
`ELT_SUB_INDIV_BIRT_FAMC` +	`FAMC` +	+	`STRING` +
`ELT_SUB_INDIV_GEN` +	`DEAT, BURI, CREM, +BAPM, BARM, BASM, +BLES, CHRA, CONF, +FCOM, ORDN, NATU, +EMIG, IMMI, CENS, +PROB, WILL, GRAD, +RETI` +	+	`NULL +STRING` +
`ELT_SUB_INDIV_ADOP` +	`ADOP` +	+	`NULL +STRING` +
`ELT_SUB_INDIV_ADOP_FAMC` +	`FAMC` +	+	`STRING` +
`ELT_SUB_INDIV_ADOP_FAMC_ADOP` +	`ADOP` +	+	`STRING` +
`ELT_SUB_INDIV_EVEN` +	`EVEN` +	+	`NULL` +
`ELT_SUB_LIO_BAPL` +	`BAPL, CONL, ENDL` +	+	`NULL` +
`ELT_SUB_LIO_BAPL_STAT` +	`STAT` +	+	`STRING` +
`ELT_SUB_LIO_BAPL_DATE` +	`DATE` +	+	`DATE` +
`ELT_SUB_LIO_BAPL_TEMP` +	`TEMP` +	+	`STRING` +
`ELT_SUB_LIO_BAPL_PLAC` +	`PLAC` +	+	`STRING` +
`ELT_SUB_LIO_SLGC` +	`SLGC` +	+	`NULL` +
`ELT_SUB_LIO_SLGC_FAMC` +	`FAMC` +	+	`STRING` +
`ELT_SUB_LSS_SLGS` +	`SLGS` +	+	`NULL` +
`ELT_SUB_LSS_SLGS_STAT` +	`STAT` +	+	`STRING` +
`ELT_SUB_LSS_SLGS_DATE` +	`DATE` +	+	`DATE` +
`ELT_SUB_LSS_SLGS_TEMP` +	`TEMP` +	+	`STRING` +
`ELT_SUB_LSS_SLGS_PLAC` +	`PLAC` +	+	`STRING` +
`ELT_SUB_MULTIM_OBJE` +	`OBJE` +	+	`NULL` +
`ELT_SUB_MULTIM_OBJE_FORM` +	`FORM` +	+	`STRING` +
`ELT_SUB_MULTIM_OBJE_TITL` +	`TITL` +	+	`STRING` +
`ELT_SUB_MULTIM_OBJE_FILE` +	`FILE` +	+	`STRING` +
`ELT_SUB_NOTE` +	`NOTE` +	+	`NULL +STRING` +
`ELT_SUB_PERS_NAME` +	`NAME` +	+	`STRING` +
`ELT_SUB_PERS_NAME_NPFX` +	`NPFX` +	+	`STRING` +
`ELT_SUB_PERS_NAME_GIVN` +	`GIVN` +	+	`STRING` +
`ELT_SUB_PERS_NAME_NICK` +	`NICK` +	+	`STRING` +
`ELT_SUB_PERS_NAME_SPFX` +	`SPFX` +	+	`STRING` +
`ELT_SUB_PERS_NAME_SURN` +	`SURN` +	+	`STRING` +
`ELT_SUB_PERS_NAME_NSFX` +	`NSFX` +	+	`STRING` +
`ELT_SUB_PLAC` +	`PLAC` +	+	`STRING` +
`ELT_SUB_PLAC_FORM` +	`FORM` +	+	`STRING` +
`ELT_SUB_SOUR` +	`SOUR` +	+	`STRING` +
`ELT_SUB_SOUR_PAGE` +	`PAGE` +	+	`STRING` +
`ELT_SUB_SOUR_EVEN` +	`EVEN` +	+	`STRING` +
`ELT_SUB_SOUR_EVEN_ROLE` +	`ROLE` +	+	`STRING` +
`ELT_SUB_SOUR_DATA` +	`DATA` +	+	`NULL` +
`ELT_SUB_SOUR_DATA_DATE` +	`DATE` +	+	`DATE` +
`ELT_SUB_SOUR_TEXT` +	`TEXT` +	+	`STRING` +
`ELT_SUB_SOUR_QUAY` +	`QUAY` +	+	`STRING` +
`ELT_SUB_REPO` +	`REPO` +	+	`STRING` +
`ELT_SUB_REPO_CALN` +	`CALN` +	+	`STRING` +
`ELT_SUB_REPO_CALN_MEDI` +	`MEDI` +	+	`STRING` +
`ELT_SUB_FAMS` +	`FAMS` +	+	`STRING` +
`ELT_USER` +	`any tag starting +with an underscore` +	+	`NULL +STRING` +

+ +

Gedcom_val types
+

+ Currently, the specific Gedcom_val types are (with val + of type Gedcom_val):
+
+ + + + + + + + + + + + + + + + + + + + + + + +

+	type checker +	cast operator +
null value +	`GEDCOM_IS_NULL(val)` +	N/A +
string +	`GEDCOM_IS_STRING(val)` +	`char* str = GEDCOM_STRING(val);` +
date +	`GEDCOM_IS_DATE(val)` +	`struct date_value dv = GEDCOM_DATE(val);`

+
+
+ The type checker returns a true or a false value according to the type +of the value, but this is in principle only necessary in the rare circumstances +that two types are possible, or where an optional value can be provided. In +most cases, the type is fixed for a specific tag.
+
+ The null value is used for when the GEDCOM spec doesn't allow a value, or +when an optional value is allowed but none is given.
+
+ The string value is the most general used value currently, for all those +values that don't have a more specific meaning. In essence, the value +that is returned by GEDCOM_STRING is always the same as the raw_value passed +to the start callback, and is thus in fact redundant.
+
+ The date value is used for all elements that return a date. (Description +of struct date_value TBD: look in the header file for the moment).
+
+

struct date_value

+This struct describes a date as given in the GEDCOM file, and has the following +definition:
+

struct date_value { + Date_value_type type; + struct date date1; + struct date date2; + char phrase[MAX_PHRASE_LEN ++ 1]; +};
+

+ It depends on the first member, the type, which members are actually relevant:
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

Date_value_type +	Meaning +	Relevant members +
`DV_NO_MODIFIER` +	just a simple date +	date1 +
`DV_BEFORE` +	a range (BEFORE date1) +	date1 +
`DV_AFTER` +	a range (AFTER date1) +	date1 +
`DV_BETWEEN` +	a range (BETWEEN date1 AND date2) +	date1, date2 +
`DV_FROM` +	a period (FROM date1) +	date1 +
`DV_TO` +	a period (TO date1) +	date1 +
`DV_FROM_TO` +	a period (FROM date1 TO date2) +	date1, date2 +
`DV_ABOUT` +	an approximation (ABOUT date1) +	date1 +
`DV_CALCULATED` +	an approximation (CALCULATED date1) +	date1 +
`DV_ESTIMATED` +	an approximation (ESTIMATED date1) +	date1 +
`DV_INTERPRETED` +	INTERPRETED date1 FROM a given free form date phrase +	date1, phrase +
`DV_PHRASE` +	a free form date phrase +	phrase +

+
+

struct date
+

+The date1 and date2 also have a strict syntax:
+

struct date { + Calendar_type cal; + char day_str[MAX_DAY_LEN + 1]; + char month_str[MAX_MONTH_LEN + +1]; + char year_str[MAX_YEAR_LEN + 1]; + + int day; + int month; + int year; + Year_type year_type; + + Date_type type; + long int sdn1; + long int sdn2; +};
+

+The first four fields are the primary fields parsed from the value in the +GEDCOM file. The day_str, month_str and


+year_str

are the literal parts of the date that denote the day, month +and year. The calendar type cal is one of (see calendar +overview LINK TBD):
+

CAL_GREGORIAN : the Gregorian calendar
CAL_JULIAN : the Julian calendar
CAL_HEBREW : the Hebrew (Jewish) calendar
CAL_FRENCH_REV : the calendar used after the French +Revolution
CAL_UNKNOWN : an unknown calendar type

+The next four fields are deduced from the first four:
+

the day is just the numeric representation of the + day_str (starting from 1)
the month is the month number of month_str + in the given calendar type (also starting from 1)
the year is the numeric representation of the +year_str

+It is possible that the year_str is given as e.g. "1677/78". + This is coming from a date in a so called "annunciation style", where +the year began on 25 March, so that "20 March 1677/78" is 20 March 1677 in +"annunciation style" and 20 March 1678 in "circumcision style" (the current +style). See calendar overview (LINK TBD).
+
+In this case, the year will contain the "circumcision style" +year (1678 in the example), and year_type will be YEAR_DOUBLE. + Normal dates will have a year_type equal to YEAR_SINGLE +.
+
+Finally, the last three fields are probably the most interesting values for +applications that want to process dates. Basically, the date is converted +to a serial day number (aka Julian day), which is the unique day number since +November 25, 4714 BC in the Gregorian calendar. The advantage of these +day numbers is that they are unique and independent of the calendar system. + Furthermore, date differences can just be computed by subtracting the +serial day numbers.
+
+However, since dates in GEDCOM are not necessarily exact (e.g. "MAR 1990"), +it is not possible to represent all GEDCOM dates with 1 serial day number. + Two cases can be distinguished:
+

Exact dates (e.g. "25 MAR 1990"):

+
These are represented by a serial day number in sdn1 + and a Date_type equal to DATE_EXACT.
+
+

Incomplete dates (e.g. "MAR 1990"):

+
These are represented by 2 serial day numbers (+sdn1 and sdn2) and a Date_type equal to + DATE_BOUNDED.
+
+For example, the Gregorian date "MAR 1990" is represented by the serial day +numbers for "1 MAR 1990" and "31 MAR 1990", and the Gregorian date "1990" +is represented by the serial day numbers for "1 JAN 1990" and "31 DEC 1990". + Similarly for the other calendar types.
+
+

+
+

$Id$
+ $Name$
+
+ + + diff --git a/doc/links.html b/doc/links.html new file mode 100644 index 0000000..c0018d7 --- /dev/null +++ b/doc/links.html @@ -0,0 +1,10 @@ + + + + GEDCOM links + + + +TO BE COMPLETED + + diff --git a/doc/usage.html b/doc/usage.html index f47684f..3d13ab0 100644 --- a/doc/usage.html +++ b/doc/usage.html @@ -2,306 +2,398 @@ Using the GEDCOM parser library - + - - + +

Using the GEDCOM parser library

-
- +
+

Start and end callbacks
Default callbacks

Other API functions

Start and end callbacks
Default callbacks
-
Debugging
Error treatment
Compatibility mode

Interface details
+

Overview
-

- The GEDCOM parser library is built as a callback-based parser (comparable -to the SAX interface of XML). It comes with:
+

Overview
+

+ The GEDCOM parser library is built as a callback-based parser (comparable + to the SAX interface of XML). It comes with:
+

a library (libgedcom.so), to be linked in the application -program
a header file (gedcom.h), to be used in the sources of -the application program
a library (libgedcom.so), to be linked in the application + program
a header file (gedcom.h), to be used in the sources +of the application program

- Next to these, there is also a data directory in $PREFIX/share/gedcom-parse - that contains some additional stuff, but which is not immediately important -at first. I'll leave the description of the data directory for later.
-
- The very simplest call of the gedcom parser is simply the following piece -of code (include of the gedcom header is assumed, as everywhere in this manual):
- + Next to these, there is also a data directory in $PREFIX/share/gedcom-parse + that contains some additional stuff, but which is not immediately important + at first. I'll leave the description of the data directory for later.
+
+ The very simplest call of the gedcom parser is simply the following piece + of code (include of the gedcom header is assumed, as everywhere in this +manual):
+

int result; - ... - result = gedcom_parse_file("myfamily.ged"); -

- Although this will not provide much information, one thing it does is parse -the entire file and return the result. The function returns 0 on success -and 1 on failure. No other information is available using this function + ...
+ result = gedcom_parse_file("myfamily.ged");
+ + Although this will not provide much information, one thing it does is parse +the entire file and return the result. The function returns 0 on success +and 1 on failure. No other information is available using this function only.
-
-The next sections will refine this to be able to have meaningful errors and -the actual data that is in the file.
-

+
+ The next sections will refine this to be able to have meaningful errors +and the actual data that is in the file.
+ +

Error handling

-Since this is a relatively simple topic, it is discussed before the actual + Since this is a relatively simple topic, it is discussed before the actual callback mechanism, although it also uses a callback...
-
-The library can be used in several different circumstances, both terminal-based -as GUI-based. Therefore, it leaves the actual display of the error -message up to the application. For this, the application needs to register -a callback before parsing the GEDCOM file, which will be called by the library +
+ The library can be used in several different circumstances, both terminal-based +as GUI-based. Therefore, it leaves the actual display of the error message +up to the application. For this, the application needs to register a +callback before parsing the GEDCOM file, which will be called by the library on errors, warnings and messages.
-
-A typical piece of code would be:
-

void my_message_handler (Gedcom_msg_type type, + + A typical piece of code would be: + + void my_message_handler (Gedcom_msg_type type, char *msg) -{ - ... -} -... - gedcom_set_message_handler(my_message_handler); -... -result = gedcom_parse_file("myfamily.ged"); - -In the above piece of code, my_message_handler is the callback + { + ... + } + ... + gedcom_set_message_handler(my_message_handler); + ... + result = gedcom_parse_file("myfamily.ged");
+

+ In the above piece of code, my_message_handler is the callback that will be called for errors (type=ERROR), warnings (


-type=WARNING

) and messages (type=MESSAGE). The -callback must have the signature as in the example. For errors, the - msg passed to the callback will have the format:
+type=WARNING) and messages (type=MESSAGE). The callback +must have the signature as in the example. For errors, the


+msg

passed to the callback will have the format:
+

Error on line <lineno>: <actual_message>
-

-Note that the entire string will be properly internationalized, and encoded -in UTF-8 (see "Why UTF-8?" LINK TBD). Also, no newline -is appended, so that the application program can use it in any way it wants. - Warnings are similar, but use "Warning" instead of "Error". Messages + + Note that the entire string will be properly internationalized, and encoded +in UTF-8 (see "Why UTF-8?" LINK TBD). Also, no newline +is appended, so that the application program can use it in any way it wants. + Warnings are similar, but use "Warning" instead of "Error". Messages are plain text, without any prefix.
-
-With this in place, the resulting code will already show errors and warnings +
+ With this in place, the resulting code will already show errors and warnings produced by the parser, e.g. on the terminal if a simple printf - is used in the message handler.
-

+ is used in the message handler.
+ +

Data callback mechanism

-The most important use of the parser is of course to get the data out of -the GEDCOM file. As already mentioned, the parser uses a callback mechanism + The most important use of the parser is of course to get the data out of +the GEDCOM file. As already mentioned, the parser uses a callback mechanism for that. In fact, the mechanism involves two levels.
-
-The primary level is that each of the sections in a GEDCOM file is notified -to the application code via a "start element" callback and an "end element" -callback (much like in a SAX interface for XML), i.e. when a line containing -a certain tag is parsed, the "start element" callback is called for that -tag, and when all its subordinate lines with their tags have been processed, -the "end element" callback is called for the original tag. Since GEDCOM -is hierarchical, this results in properly nested calls to appropriate "start +
+ The primary level is that each of the sections in a GEDCOM file is notified +to the application code via a "start element" callback and an "end element" +callback (much like in a SAX interface for XML), i.e. when a line containing +a certain tag is parsed, the "start element" callback is called for that tag, +and when all its subordinate lines with their tags have been processed, the +"end element" callback is called for the original tag. Since GEDCOM +is hierarchical, this results in properly nested calls to appropriate "start element" and "end element" callbacks.
-
-However, it would be typical for a genealogy program to support only a subset -of the GEDCOM standard, certainly a program that is still under development. - Moreover, under GEDCOM it is allowed for an application to define its -own tags, which will typically not be supported by another application. - Still, in that case, data preservation is important; it would hardly -be accepted that information that is not understood by a certain program -is just removed.
-
-Therefore, the second level of callbacks involves a "default callback". An -application needs to subscribe to callbacks for tags it does support, and -need to provide a "default callback" which will be called for tags it doesn't -support. The application can then choose to just store the information -that comes via the default callback in plain textual format.
-
-After this introduction, let's see what the API looks like...
-
+
+ However, it would be typical for a genealogy program to support only a subset +of the GEDCOM standard, certainly a program that is still under development. + Moreover, under GEDCOM it is allowed for an application to define its +own tags, which will typically not be supported by another application. + Still, in that case, data preservation is important; it would hardly +be accepted that information that is not understood by a certain program is +just removed.
+
+ Therefore, the second level of callbacks involves a "default callback". + An application needs to subscribe to callbacks for tags it does support, +and need to provide a "default callback" which will be called for tags it +doesn't support. The application can then choose to just store the +information that comes via the default callback in plain textual format.
+
+ After this introduction, let's see what the API looks like...
+
+

Start and end callbacks

Callbacks for records
-

-As a simple example, we will get some information from the header of a GEDCOM + + As a simple example, we will get some information from the header of a GEDCOM file. First, have a look at the following piece of code:
-

Gedcom_ctxt my_header_start_cb (int level, + + Gedcom_ctxt my_header_start_cb (int level, Gedcom_val xref, char *tag) -{ - printf("The header starts\n"); - return (Gedcom_ctxt)1; -} - -void my_header_end_cb (Gedcom_ctxt self) -{ - printf("The header ends, context is %d\n", self); /* context + { + printf("The header starts\n"); + return (Gedcom_ctxt)1; + } + + void my_header_end_cb (Gedcom_ctxt self) + { + printf("The header ends, context is %d\n", self); /* context will print as "1" */ -} - -... - gedcom_subscribe_to_record(REC_HEAD, my_header_start_cb, my_header_end_cb); -... -result = gedcom_parse_file("myfamily.ged"); - - Using the gedcom_subscribe_to_record function, the application -requests to use the specified callbacks as start and end callback. The end -callback is optional: you can pass NULL if you are not interested -in the end callback. The identifiers to use as first argument to the -function (here REC_HEAD) are described in TBD (use the header -file for now...). - -From the name of the function it becomes clear that this function is specific -to complete records. For the separate elements in records there is -another function, which we'll see shortly. Again, the callbacks need -to have the signatures as shown in the example. - -The Gedcom_ctxt type that is used as a result of the start callback -and as an argument to the end callback is vital for passing context necessary -for the application. This type is meant to be opaque; in fact, it's -a void pointer, so you can pass anything via it. The important thing -to know is that the context that the application returns in the start callback -will be passed in the end callback as an argument, and as we will see shortly, -also to all the directly subordinate elements of the record. - -The example passes a simple integer as context, but an application could -e.g. pass a struct that will contain the information for the -header. In the end callback, the application could then e.g. do some + } + + ... + gedcom_subscribe_to_record(REC_HEAD, my_header_start_cb, +my_header_end_cb); + ... + result = gedcom_parse_file("myfamily.ged");
+

+ Using the gedcom_subscribe_to_record function, the application +requests to use the specified callbacks as start and end callback. The end +callback is optional: you can pass NULL if you are not interested +in the end callback. The identifiers to use as first argument to the +function (here REC_HEAD) are described in the +interface details.
+
+ From the name of the function it becomes clear that this function is specific +to complete records. For the separate elements in records there is another +function, which we'll see shortly. Again, the callbacks need to have +the signatures as shown in the example.
+
+ The Gedcom_ctxt type that is used as a result of the start +callback and as an argument to the end callback is vital for passing context +necessary for the application. This type is meant to be opaque; in +fact, it's a void pointer, so you can pass anything via it. The important +thing to know is that the context that the application returns in the start +callback will be passed in the end callback as an argument, and as we will +see shortly, also to all the directly subordinate elements of the record.
+
+ The example passes a simple integer as context, but an application could +e.g. pass a struct that will contain the information for the +header. In the end callback, the application could then e.g. do some finalizing operations on the struct to put it in its database.
-
-(Note that the Gedcom_val type for the xref argument +
+ (Note that the Gedcom_val type for the xref argument was not discussed, see further for this)
-
+
+

Callbacks for elements

-We will now retrieve the SOUR field (the name of the program that wrote the -file) from the header:
-

Gedcom_ctxt my_header_source_start_cb(Gedcom_ctxt + We will now retrieve the SOUR field (the name of the program that wrote +the file) from the header: + + Gedcom_ctxt my_header_source_start_cb(Gedcom_ctxt parent, - - int + + int level, - - char* + + char* tag, - - char* + + char* raw_value, - + Gedcom_val parsed_value) -{ - char *source = GEDCOM_STRING(parsed_value); - printf("This file was written by %s\n", source); - return parent; -} - -void my_header_source_end_cb(Gedcom_ctxt parent, - + { + char *source = GEDCOM_STRING(parsed_value); + printf("This file was written by %s\n", source); + return parent; + } + + void my_header_source_end_cb(Gedcom_ctxt parent, + Gedcom_ctxt self, - + Gedcom_val parsed_value) -{ - printf("End of the source description\n"); -} - -... - gedcom_subscribe_to_element(ELT_HEAD_SOUR, - + { + printf("End of the source description\n"); + } + + ... + gedcom_subscribe_to_element(ELT_HEAD_SOUR, + my_header_source_start_cb, - + my_header_source_end_cb); -... -result = gedcom_parse_file("myfamily.ged"); - -The subscription mechanism for elements is similar, only the signatures of -the callbacks differ. The signature for the start callback shows that -the context of the parent line (e.g. the struct that describes -the header) is passed to this start callback. The callback itself returns -here the same context, but this can be its own context object of course. - The end callback is called with both the context of the parent and -the context of itself, which will be the same in the example. - -If we look at the other arguments of the start callback, we see the level -number (the initial number of the line in the GEDCOM file), the tag (e.g. -"SOUR"), and then a raw value and a parsed value. The raw value is -just the raw string that occurs as value on the line next to the tag (in -UTF-8 encoding). The parsed value is the meaningful value that is parsed -from that raw string. - -The Gedcom_val type is meant to be an opaque type. The -only thing that needs to be known about it is that it can contain specific -data types, which have to be retrieved from it using pre-defined macros. - Currently, the specific types are (with val of type -Gedcom_val): - - - - - - - - - - - - - - - - - - - - - - - - - - type checker - cast operator - null value - GEDCOM_IS_NULL(val) - N/A - string - GEDCOM_IS_STRING(val) - char* str = GEDCOM_STRING(val); - date - GEDCOM_IS_DATE(val) - struct date_value dv = GEDCOM_DATE(val) -; - - -The null value is used for when the GEDCOM spec doesn't allow a value, or -when an optional value is allowed but none is given. - -The string value is the most general used value currently, for all those -values that don't have a more specific meaning. In essence, the value -that is returned by GEDCOM_STRING is always the same as the raw_value passed -to the start callback, and is thus in fact redundant. - -The date value is used for all elements that return a date. (Description -of struct date_value TBD: look in the header file for the moment). - -The type checker returns a true or a false value according to the type of -the value, but this is in principle only necessary in the rare circumstances -that two types are possible, or where an optional value can be provided. - In most cases, the type is fixed for a specific tag (types per tag -to be described). + ... + result = gedcom_parse_file("myfamily.ged");
+

+ The subscription mechanism for elements is similar, only the signatures +of the callbacks differ. The signature for the start callback shows +that the context of the parent line (e.g. the struct that describes +the header) is passed to this start callback. The callback itself returns +here the same context, but this can be its own context object of course. The +end callback is called with both the context of the parent and the context +of itself, which will be the same in the example. Again, the list of +identifiers to use as a first argument for the subscription function are +detailed in the interface details +.
+
+ If we look at the other arguments of the start callback, we see the level +number (the initial number of the line in the GEDCOM file), the tag (e.g. +"SOUR"), and then a raw value and a parsed value. The raw value is just +the raw string that occurs as value on the line next to the tag (in UTF-8 +encoding). The parsed value is the meaningful value that is parsed from +that raw string.
+
+ The Gedcom_val type is meant to be an opaque type. The +only thing that needs to be known about it is that it can contain specific +data types, which have to be retrieved from it using pre-defined macros. These +data types are described in the +interface details.

-Some extra notes:
+ Some extra notes:
+

The Gedcom_val argument of the end callback +
The Gedcom_val argument of the end callback is currently not used. It is there for future enhancements.
There is also a Gedcom_val argument in the start -callback for records. This argument is currently a string value giving -the pointer in string form.
There is also a Gedcom_val argument in the +start callback for records. This argument is currently a string value +giving the pointer in string form.

Default callbacks
-

-TO BE COMPLETED
-

$Id$
- $Name$
-
- - - + + As described above, an application doesn't always implement the entire GEDCOM +spec, and application-specific tags may have been added by other applications. + To preserve this extra data anyway, a default callback can be registered +by the application, as in the following example:
+

void my_default_cb (Gedcom_ctxt parent, +int level, char* tag, char* raw_value) +{ + ... +} + +... + gedcom_set_default_callback(my_default_cb); +... +result = gedcom_parse_file("myfamily.ged");
+

+ This callback has a similar signature as the previous ones, but +it doesn't contain a parsed value. However, it does contain the parent +context, that was returned by the application for the most specific containing +tag that the application supported.
+
+Suppose e.g. that this callback is called for some tags in the header that +are specific to some other application, then our application could make sure +that the parent context contains the struct or object that represents the +header, and use the default callback here to add the level, tag and raw_value +as plain text in a member of that struct or object, thus preserving the information. + The application can then write this out when the data is saved again +in a GEDCOM file. To make it more specific, consider the following +example:
+

struct header { + char* source; + ... + char* extra_text; +}; + +Gedcom_ctxt my_header_start_cb(int level, Gedcom_val xref, char* tag) +{ + struct header head = my_make_header_struct(); + return (Gedcom_ctxt)head; +} + +void my_default_cb(Gedcom_ctxt parent, int level, char* tag, char* raw_value) +{ + struct header head = (struct header)parent; + my_header_add_to_extra_text(head, level, tag, raw_value); +} + +gedcom_set_default_callback(my_default_cb); +gedcom_subscribe_to_record(REC_HEAD, my_header_start, NULL); +... +result = gedcom_parse_file(filename);
+

+Note that the default callback will be called for any tag that isn't specifically +subscribed upon by the application, and can thus be called in various contexts. + For simplicity, the example above doesn't take this into account (the + parent could be of different types, depending +on the context).
+

Other API functions
+

+Although the above describes the basic interface of libgedcom, there are +some other functions that allow to customize the behaviour of the library. + These will be explained in the current section.
+

Debugging

+The library can generate various debugging output, not only from itself, +but also the debugging output generated by the yacc parser. By default, +no debugging output is generated, but this can be customized using the following +function:
+

void gedcom_set_debug_level (int level, +FILE* trace_output)
+

+The level can be one of the following values:
+

0: no debugging information (this is the default)
1: only debugging information from libgedcom +itself
2: debugging information from libgedcom and yacc

+If the trace_output is NULL, debugging information +will be written to stderr, otherwise the given file handle is +used (which must be open).
+
+

Error treatment

+One of the previous sections already described the callback to be registered +to get error messages. The library also allows to customize what happens +on an error, using the following function:
+

void gedcom_set_error_handling (Gedcom_err_mech +mechanism)
+

+The mechanism can be one of:
+

IMMED_FAIL: immediately fail the parsing +on an error (this is the default)
DEFER_FAIL: continue parsing after an +error, but return a failure code eventually
IGNORE_ERRORS: continue parsing after +an error, return success always

+This doesn't influence the generation of error or warning messages, only +the behaviour of the parser and its return code.
+
+

Compatibility mode
+

+Applications are not necessarily true to the GEDCOM spec (or use a different +version than 5.5). The intention is that the library is resilient to +this, and goes in compatibility mode for files written by specific programs +(detected via the HEAD.SOUR tag). This compatibility mode can be enabled +and disabled via the following function:
+

void gedcom_set_compat_handling + (int enable_compat)
+

+The argument can be:
+

0: disable compatibility mode
1: allow compatibility mode (this is the default)
+

+Note that, currently, no actual compatibility code is present, but this is +on the to-do list.
+

$Id: usage.html,v 1.1 2001/12/30 +22:45:43 verthezp Exp $
+ $Name$
+
+ + +

-	type checker -	cast operator -
null value -	`GEDCOM_IS_NULL(val)` -	N/A -
string -	`GEDCOM_IS_STRING(val)` -	`char* str = GEDCOM_STRING(val);` -
date -	`GEDCOM_IS_DATE(val)` -	`struct date_value dv = GEDCOM_DATE(val) -;` -

The GEDCOM parser library

Libgedcom interface details

Index

Record identifiers

Element identifiers

Gedcom_val types +

struct date_value

struct date +

Using the GEDCOM parser library

Index

Overview -

Overview +

Error handling

Data callback mechanism

Start and end callbacks

Callbacks for records -

Callbacks for elements

Default callbacks -

Other API functions +

Debugging

Error treatment

Compatibility mode +

Gedcom_val types
+

struct date
+

Overview
-

Overview
+

Callbacks for records
-

Default callbacks
-

Other API functions
+

Compatibility mode
+