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diff --git a/os400/README400 b/os400/README400 deleted file mode 100644 index 6c16de9..0000000 --- a/os400/README400 +++ /dev/null @@ -1,214 +0,0 @@ - -Implementation notes: - - This is a true OS/400 implementation, not a PASE implementation (for PASE, -use an AIX implementation). - - The biggest problem with OS/400 is EBCDIC. The current libxml2 implementation -uses UTF-8 internally. To ease encoding conversion between the calling -applications and libxml2, supplementary "convert and latch" functions are -provided (See below). To bind the EBCDIC OS/400 system calls and libxml2, -an ASCII run-time environment (QADRT) has been used and wrapper functions have -been designed. - -Other problems are: -- Source code line length: to be stored in DB2 members, source files may not - have lines longer than 100 characters. Some header and documentation files - have been modified accordingly. -- va_list dereferencing: the OS/400 implementation of va_list type is an array - but the compiler forbids explicit array dereferencing. Source files have - been updated accordingly. -- Depending on the compilation/execution environment, it is possible that - stdin/stdout/stderr are not associated with a file descriptor; as a side - effect, open() may return a file descriptor value 0, 1 or 2 that is NOT - a C standard file. Thus using such a number may be inaccurate. -- iconv_open() arguments: OS/400 uses non-standard encoding names and does not - support standard names. For this reason, a name wrapper has been designed. -- dlopen() (support for xmodule): the function and its corollaries are not - provided by the OS/400 library. However a local implementation is provided. - - -Compiling on OS/400: - -_ As a prerequisite, QADRT development environment must be installed. -_ Install the libxml2 source directory in IFS. -_ Enter shell (QSH) -_ Change current directory to the libxml2 installation directory -_ Change current directory to ./os400 -_ Edit file iniscript.sh. You may want to change tunable configuration - parameters, like debug info generation, optimisation level, listing option, - target library, zlib availability, etc. -_ Copy any file in the current directory to makelog (i.e.: - cp initscript.sh makelog): this is intended to create the makelog file with - an ASCII CCSID! -_ Enter the command "sh make.sh >makelog 2>&1' -_ Examine the makelog file to check for compilation errors. - - Leaving file initscript.sh unchanged, this will produce the following -OS/400 objects: -_ Library LIBXML2. All other objects will be stored in this library. -_ Modules for all libxml2 units, with full debug info and no code optimization. -_ Binding directory LIBXML2_A, to be used at calling program link time for - statically binding the modules (specify BNDSRVPGM(QADRTTS QGLDCLNT QGLDBRDR) - when creating a program using LIBXML2_A). -_ Service program LIBXML2. To be used at calling program run-time - when this program has dynamically bound libxml2 at link time. -_ Binding directory LIBXML2. To be used to dynamically bind libxml2 when - linking a calling program. -_ Source file LIBXML. It contains all the header members needed to compile a - C/C++ module using libxml2. -_ Standard and additional C/C++ libxml2 header members (possibly renamed) in - file LIBXML. -_ IFS directory /libxml2 with subdirectory include/libxml containing all - C/C++ header files for IFS-based compilation. -_ Source file LIBXMLRPG. It contains all the include members needed to compile a - ILE/RPG module/program using libxml2 (ILE/RPG binding). -_ ILE/RPG binding include members (possibly renamed) in file LIBXMLRPG. -_ IFS subdirectory /libxml2/include/libxmlrpg containing all ILE/RPG include - files for IFS-based compilation. - - -Renamed header files in DB2 members: - DB2 member names are limited to 10 characters, thus the following C/C++ -header members are renamed as: - parserInternals.h --> PARSERINTE - schemasInternals.h --> SCHEMASINT - xmlautomata.h --> XMLAUTOMAT - xmlschemastype.h --> SCHMTYPES - xpathInternals.h --> XPATHINTER -IFS header files are NOT renamed. -ILE/RPG headers are processed likewise. - - -Special programming consideration: - -QADRT being used, the following points must be considered: -_ If static binding is used, service program QADRTTS must be linked too. -_ The EBCDIC CCSID used by QADRT is 37 by default, NOT THE JOB'S CCSID. If - another EBCDIC CCSID is required, it must be set via a locale through a call - to setlocale_a (QADRT's setlocale() ASCII wrapper) with category LC_ALL or - LC_CTYPE, or by setting environment variable QADRT_ENV_LOCALE to the locale - object path before executing the program. -_ Always use *IFSIO or *IFS64IO to compile calling programs. - - - -Supplementary (non libxml2 standard) support procedures for OS/400. - - As cited above, there are some procedures to ease encoding conversion of -libxml2 function arguments and results: the mechanism is based on -dictionaries. The functions convert a string, latch the result in a dictionary -to ensure its persistence and return its address. It is the caller's -responsibility to clean the dictionary when it becomes too big or disappears. - -The procedures are: - -#include <libxml/transcode.h> - -const char * xmlTranscodeResult(const xmlChar * s, - const char * encoding, - xmlDictPtr * dict, - void (*freeproc)(const void *)); - -const xmlChar * xmlTranscodeString(const char * s, - const char * encoding, - xmlDictPtr * dict); - -const xmlChar * xmlTranscodeWString(const char * s, - const char * encoding, - xmlDictPtr * dict); - -const xmlChar * xmlTranscodeWString(const char * s, - const char * encoding, - xmlDictPtr * dict); - -where: -s is the string to translate. -encoding is the alternate character encoding. If null, the current job's - encoding (CCSID) is used. -dict is the address of the latching directory. If NULL, the procedure - functions as a simple non-latching encoding converter and - its result value should be freed by the caller. -freeproc is a procedure to release the original string, or NULL. - -xmlTranscodeResult() converts from UTF-8 to the given alternate encoding. -xmlTranscodeString() converts from the given 8-bit encoding to UTF-8 (note that - UTF-8 itself is considered as a 8-bit encoding). -xmlTranscodeWString() converts from the given 16-bit encoding to UTF-8. -xmlTranscodeHString() converts from the given 32-bit encoding to UTF-8. - - -To shorten statements using these functions, shorthands are defined: - -xmlTR for xmlTranscodeResult -xmlTS for xmlTranscodeString -xmlTW for xmlTranscodeWString -xmlTH for xmlTranscodeHstring - -These shorthands may be disabled by defining XML_NO_SHORT_NAMES before -libxml/transcode.h inclusion. - -A directory pointer must be preset to NULL before the first call using it to -one of the above procedure. - -To release a latching directory, use function - -void xmlZapDict(xmlDictPtr * dict); - - -Example: - -#include <libxml/transcode.h> -#include <libxml/tree.h> - -xmlDocPtr mySimpleXMLDoc(char * element, char * text) -{ - xmlDocPtr doc; - xmlNodePtr node; - xmlDictPtr dict = NULL; - - /* element and text are encoded in the current job's encoding. */ - - doc = xmlNewDoc(); - xmlNewTextChild((xmlNodePtr) doc, NULL, xmlTS(element, NULL, - &dict), xmlTS(text, NULL, &dict)); - xmlZapDict(&dict); - return doc; -} - - -Additionally, a formatter into latched/dynamic storage is provided: - -const char * xmlVasprintf(xmlDictPtr * dict, - const char * encoding, - const xmlChar * fmt, - va_list args); - - - -ILE/RPG binding: - - All standard types and procedures are provided. Since ILE/RPG does not -support macros, they have not been ported, with the exceptions of the more -useful ones and the global/threaded variables access macros. These variables -can be read with function get_xxx(void), where xxxx is the name of the -variable; they may be set by calling function set_xxxx(value), where value is -of the same type as the variable. - - The C va_list is not implemented as such in ILE/RPG. Functions implementing -va_list and associated methods are provided: - - /include "libxmlrpg/xmlstdarg" - - d xmlVaStart pr - d list like(xmlVaList) - d lastargaddr * value - d lastargsize 10u 0 value - - d xmlVaArg pr - d list like(xmlVaList) - d dest * value - d argsize 10i 0 value - - d xmlVaEnd pr - d list like(xmlVaList) |