1
2Implementation notes:
3
4 This is a true OS/400 ILE implementation, not a PASE implementation (for
5PASE, use AIX implementation).
6
7 The biggest problem with OS/400 is EBCDIC. Libcurl implements an internal
8conversion mechanism, but it has been designed for computers that have a
9single native character set. OS/400 default native character set varies
10depending on the country for which it has been localized. And more, a job
11may dynamically alter its "native" character set.
12 Several characters that do not have fixed code in EBCDIC variants are
13used in libcurl strings. As a consequence, using the existing conversion
14mechanism would have lead in a localized binary library - not portable across
15countries.
16 For this reason, and because libcurl was originally designed for ASCII based
17operating systems, the current OS/400 implementation uses ASCII as internal
18character set. This has been accomplished using the QADRT library and
19include files, a C and system procedures ASCII wrapper library. See IBM QADRT
20description for more information.
21 This then results in libcurl being an ASCII library: any function string
22argument is taken/returned in ASCII and a C/C++ calling program built around
23QADRT may use libcurl functions as on any other platform.
24 QADRT does not define ASCII wrappers for all C/system procedures: the
25OS/400 configuration header file and an additional module (os400sys.c) define
26some more of them, that are used by libcurl and that QADRT left out.
27 To support all the different variants of EBCDIC, non-standard wrapper
28procedures have been added to libcurl on OS/400: they provide an additional
29CCSID (numeric Coded Character Set ID specific to OS/400) parameter for each
30string argument. Callback procedures arguments giving access to strings are
31NOT converted, so text gathered this way is (probably !) ASCII.
32
33 Another OS/400 problem comes from the fact that the last fixed argument of a
34vararg procedure may not be of type char, unsigned char, short or unsigned
35short. Enums that are internally implemented by the C compiler as one of these
36types are also forbidden. Libcurl uses enums as vararg procedure tagfields...
37Happily, there is a pragma forcing enums to type "int". The original libcurl
38header files are thus altered during build process to use this pragma, in
39order to force libcurl enums of being type int (the pragma disposition in use
40before inclusion is restored before resuming the including unit compilation).
41
42 Non-standard EBCDIC wrapper prototypes are defined in an additional header
43file: ccsidcurl.h. These should be self-explanatory to an OS/400-aware
44designer. CCSID 0 can be used to select the current job's CCSID.
45 Wrapper procedures with variable arguments are described below:
46
47_ curl_easy_setopt_ccsid()
48 Variable arguments are a string pointer and a CCSID (unsigned int) for
49options:
50 CURLOPT_ABSTRACT_UNIX_SOCKET
51 CURLOPT_ACCEPT_ENCODING
52 CURLOPT_ALTSVC
53 CURLOPT_AWS_SIGV4
54 CURLOPT_CAINFO
55 CURLOPT_CAPATH
56 CURLOPT_COOKIE
57 CURLOPT_COOKIEFILE
58 CURLOPT_COOKIEJAR
59 CURLOPT_COOKIELIST
60 CURLOPT_CRLFILE
61 CURLOPT_CUSTOMREQUEST
62 CURLOPT_DEFAULT_PROTOCOL
63 CURLOPT_DNS_INTERFACE
64 CURLOPT_DNS_LOCAL_IP4
65 CURLOPT_DNS_LOCAL_IP6
66 CURLOPT_DNS_SERVERS
67 CURLOPT_DOH_URL
68 CURLOPT_EGDSOCKET
69 CURLOPT_FTPPORT
70 CURLOPT_FTP_ACCOUNT
71 CURLOPT_FTP_ALTERNATIVE_TO_USER
72 CURLOPT_HAPROXY_CLIENT_IP
73 CURLOPT_HSTS
74 CURLOPT_INTERFACE
75 CURLOPT_ISSUERCERT
76 CURLOPT_KEYPASSWD
77 CURLOPT_KRBLEVEL
78 CURLOPT_LOGIN_OPTIONS
79 CURLOPT_MAIL_AUTH
80 CURLOPT_MAIL_FROM
81 CURLOPT_NETRC_FILE
82 CURLOPT_NOPROXY
83 CURLOPT_PASSWORD
84 CURLOPT_PINNEDPUBLICKEY
85 CURLOPT_PRE_PROXY
86 CURLOPT_PROTOCOLS_STR
87 CURLOPT_PROXY
88 CURLOPT_PROXYPASSWORD
89 CURLOPT_PROXYUSERNAME
90 CURLOPT_PROXYUSERPWD
91 CURLOPT_PROXY_CAINFO
92 CURLOPT_PROXY_CAPATH
93 CURLOPT_PROXY_CRLFILE
94 CURLOPT_PROXY_ISSUERCERT
95 CURLOPT_PROXY_KEYPASSWD
96 CURLOPT_PROXY_PINNEDPUBLICKEY
97 CURLOPT_PROXY_SERVICE_NAME
98 CURLOPT_PROXY_SSLCERT
99 CURLOPT_PROXY_SSLCERTTYPE
100 CURLOPT_PROXY_SSLKEY
101 CURLOPT_PROXY_SSLKEYTYPE
102 CURLOPT_PROXY_SSL_CIPHER_LIST
103 CURLOPT_PROXY_TLS13_CIPHERS
104 CURLOPT_PROXY_TLSAUTH_PASSWORD
105 CURLOPT_PROXY_TLSAUTH_TYPE
106 CURLOPT_PROXY_TLSAUTH_USERNAME
107 CURLOPT_RANDOM_FILE
108 CURLOPT_RANGE
109 CURLOPT_REDIR_PROTOCOLS_STR
110 CURLOPT_REFERER
111 CURLOPT_REQUEST_TARGET
112 CURLOPT_RTSP_SESSION_ID
113 CURLOPT_RTSP_STREAM_URI
114 CURLOPT_RTSP_TRANSPORT
115 CURLOPT_SASL_AUTHZID
116 CURLOPT_SERVICE_NAME
117 CURLOPT_SOCKS5_GSSAPI_SERVICE
118 CURLOPT_SSH_HOST_PUBLIC_KEY_MD5
119 CURLOPT_SSH_HOST_PUBLIC_KEY_SHA256
120 CURLOPT_SSH_KNOWNHOSTS
121 CURLOPT_SSH_PRIVATE_KEYFILE
122 CURLOPT_SSH_PUBLIC_KEYFILE
123 CURLOPT_SSLCERT
124 CURLOPT_SSLCERTTYPE
125 CURLOPT_SSLENGINE
126 CURLOPT_SSLKEY
127 CURLOPT_SSLKEYTYPE
128 CURLOPT_SSL_CIPHER_LIST
129 CURLOPT_SSL_EC_CURVES
130 CURLOPT_TLS13_CIPHERS
131 CURLOPT_TLSAUTH_PASSWORD
132 CURLOPT_TLSAUTH_TYPE
133 CURLOPT_TLSAUTH_USERNAME
134 CURLOPT_UNIX_SOCKET_PATH
135 CURLOPT_URL
136 CURLOPT_USERAGENT
137 CURLOPT_USERNAME
138 CURLOPT_USERPWD
139 CURLOPT_XOAUTH2_BEARER
140 All blob options are also supported.
141 In all other cases, it ignores the ccsid parameter and behaves as
142curl_easy_setopt().
143 Note that CURLOPT_ERRORBUFFER is not in the list above, since it gives the
144address of an (empty) character buffer, not the address of a string.
145CURLOPT_POSTFIELDS stores the address of static binary data (of type void *)
146and thus is not converted. If CURLOPT_COPYPOSTFIELDS is issued after
147CURLOPT_POSTFIELDSIZE != -1, the data size is adjusted according to the
148CCSID conversion result length.
149
150_ curl_formadd_ccsid()
151 In the variable argument list, string pointers should be followed by a (long)
152CCSID for the following options:
153 CURLFORM_BUFFER
154 CURLFORM_CONTENTTYPE
155 CURLFORM_COPYCONTENTS
156 CURLFORM_COPYNAME
157 CURLFORM_FILE
158 CURLFORM_FILECONTENT
159 CURLFORM_FILENAME
160 CURLFORM_PTRNAME
161 If taken from an argument array, an additional array entry must follow each
162entry containing one of the above option. This additional entry holds the CCSID
163in its value field, and the option field is meaningless.
164 It is not possible to have a string pointer and its CCSID across a function
165parameter/array boundary.
166 Please note that CURLFORM_PTRCONTENTS and CURLFORM_BUFFERPTR are considered
167unconvertible strings and thus are NOT followed by a CCSID.
168
169_ curl_easy_getinfo_ccsid()
170 The following options are followed by a 'char * *' and a CCSID. Unlike
171curl_easy_getinfo(), the value returned in the pointer should be released with
172curl_free() after use:
173 CURLINFO_CONTENT_TYPE
174 CURLINFO_EFFECTIVE_URL
175 CURLINFO_FTP_ENTRY_PATH
176 CURLINFO_LOCAL_IP
177 CURLINFO_PRIMARY_IP
178 CURLINFO_REDIRECT_URL
179 CURLINFO_REFERER
180 CURLINFO_RTSP_SESSION_ID
181 CURLINFO_SCHEME
182 Likewise, the following options are followed by a struct curl_slist * * and a
183CCSID.
184 CURLINFO_COOKIELIST
185 CURLINFO_SSL_ENGINES
186Lists returned should be released with curl_slist_free_all() after use.
187 Option CURLINFO_CERTINFO is followed by a struct curl_certinfo * * and a
188CCSID. Returned structures should be freed with curl_certinfo_free_all()
189after use.
190 Other options are processed like in curl_easy_getinfo().
191
192_ curl_easy_strerror_ccsid(), curl_multi_strerror_ccsid(),
193curl_share_strerror_ccsid() and curl_url_strerror_ccsid() work as their
194non-ccsid version and return a string encoded in the additional ccsid
195parameter. These strings belong to libcurl and may not be freed by the caller.
196A subsequent call to the same procedure in the same thread invalidates the
197previous result.
198
199_ curl_pushheader_bynum_cssid() and curl_pushheader_byname_ccsid()
200 Although the prototypes are self-explanatory, the returned string pointer
201should be released with curl_free() after use, as opposite to the non-ccsid
202versions of these procedures.
203 Please note that HTTP2 is not (yet) implemented on OS/400, thus these
204functions will always return NULL.
205
206_ curl_easy_option_by_name_ccsid() returns a pointer to an untranslated option
207metadata structure. As each curl_easyoption structure holds the option name in
208ASCII, the curl_easy_option_get_name_ccsid() function allows getting it in any
209supported ccsid. However the caller should release the returned pointer with
210curl_free() after use.
211
212_ curl_easy_header_ccsid() works as its non-CCSID counterpart but requires an
213additional ccsid parameter specifying the name parameter encoding. The output
214hout parameter is kept in libcurl's encoding and should not be altered.
215
216_ curl_from_ccsid() and curl_to_ccsid() are string encoding conversion
217functions between ASCII (latin1) and the given CCSID. The first parameter is
218the source string, the second is the CCSID and the returned value is a pointer
219to the dynamically allocated string. These functions do not impact on Curl's
220behavior and are only provided for user convenience. After use, returned values
221must be released with curl_free().
222
223
224 Standard compilation environment does support neither autotools nor make;
225in fact, very few common utilities are available. As a consequence, the
226config-os400.h has been coded manually and the compilation scripts are
227a set of shell scripts stored in subdirectory packages/OS400.
228
229 The "curl" command and the test environment are currently not supported on
230OS/400.
231
232
233Protocols currently implemented on OS/400:
234_ DICT
235_ FILE
236_ FTP
237_ FTPS
238_ FTP with secure transmission
239_ GOPHER
240_ HTTP
241_ HTTPS
242_ IMAP
243_ IMAPS
244_ IMAP with secure transmission
245_ LDAP
246_ POP3
247_ POP3S
248_ POP3 with secure transmission
249_ RTSP
250_ SCP if libssh2 is enabled
251_ SFTP if libssh2 is enabled
252_ SMTP
253_ SMTPS
254_ SMTP with secure transmission
255_ TELNET
256_ TFTP
257
258
259
260Compiling on OS/400:
261
262 These instructions targets people who knows about OS/400, compiling, IFS and
263archive extraction. Do not ask questions about these subjects if you're not
264familiar with.
265
266_ As a prerequisite, QADRT development environment must be installed.
267 For more information on downloading and installing the QADRT development kit,
268 please see https://www.ibm.com/support/pages/node/6258183
269_ If data compression has to be supported, ZLIB development environment must
270 be installed.
271_ Likewise, if SCP and SFTP protocols have to be compiled in, LIBSSH2
272 developent environment must be installed.
273_ Install the curl source directory in IFS. Do NOT install it in the
274 installation target directory (which defaults to /curl).
275_ Enter Qshell (QSH, not PASE)
276_ Change current directory to the curl installation directory
277_ Change current directory to ./packages/OS400
278- If you want to change the default configuration parameters like debug info
279 generation, optimization level, listing option, target library, ZLIB/LIBSSH2
280 availability and location, etc., copy file config400.default to
281 config400.override and edit the latter. Do not edit the original default file
282 as it might be overwritten by a subsequent source installation.
283_ Copy any file in the current directory to makelog (i.e.:
284 cp initscript.sh makelog): this is intended to create the makelog file with
285 an ASCII CCSID!
286_ Enter the command "sh makefile.sh > makelog 2>&1"
287_ Examine the makelog file to check for compilation errors. CZM0383 warnings on
288 C or system standard API come from QADRT inlining and can safely be ignored.
289
290 Without configuration parameters override, this will produce the following
291OS/400 objects:
292_ Library CURL. All other objects will be stored in this library.
293_ Modules for all libcurl units.
294_ Binding directory CURL_A, to be used at calling program link time for
295 statically binding the modules (specify BNDSRVPGM(QADRTTS QGLDCLNT QGLDBRDR)
296 when creating a program using CURL_A).
297_ Service program CURL.<soname>, where <soname> is extracted from the
298 lib/Makefile.am VERSION variable. To be used at calling program run-time
299 when this program has dynamically bound curl at link time.
300_ Binding directory CURL. To be used to dynamically bind libcurl when linking a
301 calling program.
302- CLI tool bound program CURL.
303- CLI command CURL.
304_ Source file H. It contains all the include members needed to compile a C/C++
305 module using libcurl, and an ILE/RPG /copy member for support in this
306 language.
307_ Standard C/C++ libcurl include members in file H.
308_ CCSIDCURL member in file H. This defines the non-standard EBCDIC wrappers for
309 C and C++.
310_ CURL.INC member in file H. This defines everything needed by an ILE/RPG
311 program using libcurl.
312_ IFS directory /curl/include/curl containing the C header files for IFS source
313 C/C++ compilation and curl.inc.rpgle for IFS source ILE/RPG compilation.
314- IFS link /curl/bin/curl to CLI tool program.
315
316
317Special programming consideration:
318
319QADRT being used, the following points must be considered:
320_ If static binding is used, service program QADRTTS must be linked too.
321_ The EBCDIC CCSID used by QADRT is 37 by default, NOT THE JOB'S CCSID. If
322 another EBCDIC CCSID is required, it must be set via a locale through a call
323 to setlocale_a (QADRT's setlocale() ASCII wrapper) with category LC_ALL or
324 LC_CTYPE, or by setting environment variable QADRT_ENV_LOCALE to the locale
325 object path before executing the program.
326_ Do not use original source include files unless you know what you are doing.
327 Use the installed members instead (in /QSYS.LIB/CURL.LIB/H.FILE and
328 /curl/include/curl).
329
330
331
332ILE/RPG support:
333
334 Since most of the ILE OS/400 programmers use ILE/RPG exclusively, a
335definition /INCLUDE member is provided for this language. To include all
336libcurl definitions in an ILE/RPG module, line
337
338 h bnddir('CURL/CURL')
339
340must figure in the program header, and line
341
342 d/include curl/h,curl.inc
343
344in the global data section of the module's source code.
345
346 No vararg procedure support exists in ILE/RPG: for this reason, the following
347considerations apply:
348_ Procedures curl_easy_setopt_long(), curl_easy_setopt_object(),
349 curl_easy_setopt_function(), curl_easy_setopt_offset() and
350 curl_easy_setopt_blob() are all alias prototypes to curl_easy_setopt(), but
351 with different parameter lists.
352_ Procedures curl_easy_getinfo_string(), curl_easy_getinfo_long(),
353 curl_easy_getinfo_double(), curl_easy_getinfo_slist(),
354 curl_easy_getinfo_ptr(), curl_easy_getinfo_socket() and
355 curl_easy_getinfo_off_t() are all alias prototypes to curl_easy_getinfo(),
356 but with different parameter lists.
357_ Procedures curl_multi_setopt_long(), curl_multi_setopt_object(),
358 curl_multi_setopt_function() and curl_multi_setopt_offset() are all alias
359 prototypes to curl_multi_setopt(), but with different parameter lists.
360_ Procedures curl_share_setopt_int(), curl_share_setopt_ptr() and
361 curl_share_setopt_proc() are all alias prototypes to curl_share_setopt,
362 but with different parameter lists.
363_ Procedure curl_easy_setopt_blob_ccsid() is an alias of
364 curl_easy_setopt_ccsid() supporting blob encoding conversion.
365_ The prototype of procedure curl_formadd() allows specifying a pointer option
366 and the CURLFORM_END option. This makes possible to use an option array
367 without any additional definition. If some specific incompatible argument
368 list is used in the ILE/RPG program, the latter must define a specialised
369 alias. The same applies to curl_formadd_ccsid() too.
370_ Since V7R4M0, procedure overloading is used to emulate limited "vararg-like"
371 definitions of curl_easy_setopt(), curl_multi_setopt(), curl_share_setopt()
372 and curl_easy_getinfo(). Blob and CCSID alternatives are NOT included in
373 overloading.
374
375 Since RPG cannot cast a long to a pointer, procedure curl_form_long_value()
376is provided for that purpose: this allows storing a long value in the
377curl_forms array. Please note the form API is deprecated and the MIME API
378should be used instead.
379
380
381CLI tool:
382
383 The build system provides it as a bound program, an IFS link to it and a
384simple CL command. The latter however is not able to provide a different
385parameter for each option since there are too many of those; instead,
386parameters are entered in a single field subject to quoting and escaping, in
387the same form as expected by the standard CLI program.
388 Care must be taken about the program output encoding: by default, it is sent
389to the standard output and is thus subject to transcoding. It is therefore
390recommended to use option "--output" to redirect output to a specific IFS file.
391Similar problems may occur about the standard input encoding.
392
