1/*
2 * Copyright (c) 2014-2015, Juniper Networks, Inc.
3 * All rights reserved.
4 * This SOFTWARE is licensed under the LICENSE provided in the
5 * ../Copyright file. By downloading, installing, copying, or otherwise
6 * using the SOFTWARE, you agree to be bound by the terms of that
7 * LICENSE.
8 * Phil Shafer, July 2014
9 */
10
11/**
12 * libxo provides a means of generating text, XML, JSON, and HTML output
13 * using a single set of function calls, maximizing the value of output
14 * while minimizing the cost/impact on the code.
15 *
16 * Full documentation is available in ./doc/libxo.txt or online at:
17 *   http://juniper.github.io/libxo/libxo-manual.html
18 */
19
20#ifndef INCLUDE_XO_H
21#define INCLUDE_XO_H
22
23#include <stdio.h>
24#include <sys/types.h>
25#include <stdarg.h>
26#include <limits.h>
27#include <stdlib.h>
28#include <errno.h>
29
30#ifdef __dead2
31#define NORETURN __dead2
32#else
33#define NORETURN
34#endif /* __dead2 */
35
36/*
37 * Normally we'd use the HAVE_PRINTFLIKE define triggered by the
38 * --enable-printflike option to configure, but we don't install
39 * our internal "xoconfig.h", and I'd rather not.  Taking the
40 * coward's path, we'll turn it on inside a #if that allows
41 * others to turn it off where needed.  Not ideal, but functional.
42 */
43#if !defined(NO_PRINTFLIKE)
44#if defined(__linux) && !defined(__printflike)
45#define __printflike(_x, _y) __attribute__((__format__ (__printf__, _x, _y)))
46#endif
47#define PRINTFLIKE(_x, _y) __printflike(_x, _y)
48#else
49#define PRINTFLIKE(_x, _y)
50#endif /* NO_PRINTFLIKE */
51
52/** Formatting types */
53typedef unsigned short xo_style_t;
54#define XO_STYLE_TEXT	0	/** Generate text output */
55#define XO_STYLE_XML	1	/** Generate XML output */
56#define XO_STYLE_JSON	2	/** Generate JSON output */
57#define XO_STYLE_HTML	3	/** Generate HTML output */
58#define XO_STYLE_SDPARAMS 4	/* Generate syslog structured data params */
59#define XO_STYLE_ENCODER 5	/* Generate calls to external encoder */
60
61/** Flags for libxo */
62typedef unsigned long long xo_xof_flags_t;
63#define XOF_BIT(_n) ((xo_xof_flags_t) 1 << (_n))
64#define XOF_CLOSE_FP	XOF_BIT(0) /** Close file pointer on xo_close() */
65#define XOF_PRETTY	XOF_BIT(1) /** Make 'pretty printed' output */
66#define XOF_LOG_SYSLOG	XOF_BIT(2) /** Log (on stderr) our syslog content */
67#define XOF_RESV3	XOF_BIT(3) /* Unused */
68
69#define XOF_WARN	XOF_BIT(4) /** Generate warnings for broken calls */
70#define XOF_XPATH	XOF_BIT(5) /** Emit XPath attributes in HTML  */
71#define XOF_INFO	XOF_BIT(6) /** Emit additional info fields (HTML) */
72#define XOF_WARN_XML	XOF_BIT(7) /** Emit warnings in XML (on stdout) */
73
74#define XOF_NO_ENV	XOF_BIT(8) /** Don't look at LIBXO_OPTIONS env var */
75#define XOF_NO_VA_ARG	XOF_BIT(9) /** Don't advance va_list w/ va_arg() */
76#define XOF_DTRT	XOF_BIT(10) /** Enable "do the right thing" mode */
77#define XOF_KEYS	XOF_BIT(11) /** Flag 'key' fields for xml and json */
78
79#define XOF_IGNORE_CLOSE XOF_BIT(12) /** Ignore errors on close tags */
80#define XOF_NOT_FIRST	XOF_BIT(13) /* Not the first item (JSON)  */
81#define XOF_NO_LOCALE	XOF_BIT(14) /** Don't bother with locale */
82#define XOF_RESV15	XOF_BIT(15) /* Unused */
83
84#define XOF_NO_TOP	XOF_BIT(16) /** Don't emit the top braces in JSON */
85#define XOF_RESV17	XOF_BIT(17) /* Unused  */
86#define XOF_UNITS	XOF_BIT(18) /** Encode units in XML */
87#define XOF_RESV19	XOF_BIT(19) /* Unused */
88
89#define XOF_UNDERSCORES	XOF_BIT(20) /** Replace dashes with underscores (JSON)*/
90#define XOF_COLUMNS	XOF_BIT(21) /** xo_emit should return a column count */
91#define XOF_FLUSH	XOF_BIT(22) /** Flush after each xo_emit call */
92#define XOF_FLUSH_LINE	XOF_BIT(23) /** Flush after each newline */
93
94#define XOF_NO_CLOSE	XOF_BIT(24) /** xo_finish won't close open elements */
95#define XOF_COLOR_ALLOWED XOF_BIT(25) /** Allow color/effects to be enabled */
96#define XOF_COLOR	XOF_BIT(26) /** Enable color and effects */
97#define XOF_NO_HUMANIZE	XOF_BIT(27) /** Block the {h:} modifier */
98
99#define XOF_LOG_GETTEXT	XOF_BIT(28) /** Log (stderr) gettext lookup strings */
100#define XOF_UTF8	XOF_BIT(29) /** Force text output to be UTF8 */
101#define XOF_RETAIN_ALL	XOF_BIT(30) /** Force use of XOEF_RETAIN */
102#define XOF_RETAIN_NONE	XOF_BIT(31) /** Prevent use of XOEF_RETAIN */
103
104#define XOF_COLOR_MAP	XOF_BIT(32) /** Color map has been initialized */
105
106typedef unsigned xo_emit_flags_t; /* Flags to xo_emit() and friends */
107#define XOEF_RETAIN	(1<<0)	  /* Retain parsed formatting information */
108
109/*
110 * The xo_info_t structure provides a mapping between names and
111 * additional data emitted via HTML.
112 */
113typedef struct xo_info_s {
114    const char *xi_name;	/* Name of the element */
115    const char *xi_type;	/* Type of field */
116    const char *xi_help;	/* Description of field */
117} xo_info_t;
118
119#define XO_INFO_NULL NULL, NULL, NULL /* Use '{ XO_INFO_NULL }' to end lists */
120
121struct xo_handle_s;		/* Opaque structure forward */
122typedef struct xo_handle_s xo_handle_t; /* Handle for XO output */
123
124/*
125 * Early versions of the API used "int" instead of "size_t" for buffer
126 * sizes.  We want to fix this but allow for backwards compatibility
127 * where needed.
128 */
129#ifdef USE_INT_RETURN_CODES
130typedef int xo_ssize_t;		/* Buffer size */
131#else /* USE_INT_RETURN_CODES */
132typedef ssize_t xo_ssize_t;	/* Buffer size */
133#endif /* USE_INT_RETURN_CODES */
134
135typedef xo_ssize_t (*xo_write_func_t)(void *, const char *);
136typedef void (*xo_close_func_t)(void *);
137typedef int (*xo_flush_func_t)(void *);
138typedef void *(*xo_realloc_func_t)(void *, size_t);
139typedef void (*xo_free_func_t)(void *);
140
141/*
142 * The formatter function mirrors "vsnprintf", with an additional argument
143 * of the xo handle.  The caller should return the number of bytes _needed_
144 * to fit the data, even if this exceeds 'len'.
145 */
146typedef xo_ssize_t (*xo_formatter_t)(xo_handle_t *, char *, xo_ssize_t,
147				const char *, va_list);
148typedef void (*xo_checkpointer_t)(xo_handle_t *, va_list, int);
149
150xo_handle_t *
151xo_create (xo_style_t style, xo_xof_flags_t flags);
152
153xo_handle_t *
154xo_create_to_file (FILE *fp, xo_style_t style, xo_xof_flags_t flags);
155
156void
157xo_destroy (xo_handle_t *xop);
158
159void
160xo_set_writer (xo_handle_t *xop, void *opaque, xo_write_func_t write_func,
161	       xo_close_func_t close_func, xo_flush_func_t flush_func);
162
163void
164xo_set_allocator (xo_realloc_func_t realloc_func, xo_free_func_t free_func);
165
166void
167xo_set_style (xo_handle_t *xop, xo_style_t style);
168
169xo_style_t
170xo_get_style (xo_handle_t *xop);
171
172int
173xo_set_style_name (xo_handle_t *xop, const char *style);
174
175int
176xo_set_options (xo_handle_t *xop, const char *input);
177
178xo_xof_flags_t
179xo_get_flags (xo_handle_t *xop);
180
181void
182xo_set_flags (xo_handle_t *xop, xo_xof_flags_t flags);
183
184void
185xo_clear_flags (xo_handle_t *xop, xo_xof_flags_t flags);
186
187int
188xo_set_file_h (xo_handle_t *xop, FILE *fp);
189
190int
191xo_set_file (FILE *fp);
192
193void
194xo_set_info (xo_handle_t *xop, xo_info_t *infop, int count);
195
196void
197xo_set_formatter (xo_handle_t *xop, xo_formatter_t func, xo_checkpointer_t);
198
199void
200xo_set_depth (xo_handle_t *xop, int depth);
201
202xo_ssize_t
203xo_emit_hv (xo_handle_t *xop, const char *fmt, va_list vap);
204
205xo_ssize_t
206xo_emit_h (xo_handle_t *xop, const char *fmt, ...);
207
208xo_ssize_t
209xo_emit (const char *fmt, ...);
210
211xo_ssize_t
212xo_emit_hvf (xo_handle_t *xop, xo_emit_flags_t flags,
213	     const char *fmt, va_list vap);
214
215xo_ssize_t
216xo_emit_hf (xo_handle_t *xop, xo_emit_flags_t flags, const char *fmt, ...);
217
218xo_ssize_t
219xo_emit_f (xo_emit_flags_t flags, const char *fmt, ...);
220
221PRINTFLIKE(2, 0)
222static inline int
223xo_emit_hvp (xo_handle_t *xop, const char *fmt, va_list vap)
224{
225    return xo_emit_hv(xop, fmt, vap);
226}
227
228PRINTFLIKE(2, 3)
229static inline int
230xo_emit_hp (xo_handle_t *xop, const char *fmt, ...)
231{
232    va_list vap;
233    va_start(vap, fmt);
234    int rc = xo_emit_hv(xop, fmt, vap);
235    va_end(vap);
236    return rc;
237}
238
239PRINTFLIKE(1, 2)
240static inline int
241xo_emit_p (const char *fmt, ...)
242{
243    va_list vap;
244    va_start(vap, fmt);
245    int rc = xo_emit_hv(NULL, fmt, vap);
246    va_end(vap);
247    return rc;
248}
249
250PRINTFLIKE(3, 0)
251static inline int
252xo_emit_hvfp (xo_handle_t *xop, xo_emit_flags_t flags,
253	      const char *fmt, va_list vap)
254{
255    return xo_emit_hvf(xop, flags, fmt, vap);
256}
257
258PRINTFLIKE(3, 4)
259static inline int
260xo_emit_hfp (xo_handle_t *xop, xo_emit_flags_t flags, const char *fmt, ...)
261{
262    va_list vap;
263    va_start(vap, fmt);
264    int rc = xo_emit_hvf(xop, flags, fmt, vap);
265    va_end(vap);
266    return rc;
267}
268
269PRINTFLIKE(2, 3)
270static inline int
271xo_emit_fp (xo_emit_flags_t flags, const char *fmt, ...)
272{
273    va_list vap;
274    va_start(vap, fmt);
275    int rc = xo_emit_hvf(NULL, flags, fmt, vap);
276    va_end(vap);
277    return rc;
278}
279
280xo_ssize_t
281xo_open_container_h (xo_handle_t *xop, const char *name);
282
283xo_ssize_t
284xo_open_container (const char *name);
285
286xo_ssize_t
287xo_open_container_hd (xo_handle_t *xop, const char *name);
288
289xo_ssize_t
290xo_open_container_d (const char *name);
291
292xo_ssize_t
293xo_close_container_h (xo_handle_t *xop, const char *name);
294
295xo_ssize_t
296xo_close_container (const char *name);
297
298xo_ssize_t
299xo_close_container_hd (xo_handle_t *xop);
300
301xo_ssize_t
302xo_close_container_d (void);
303
304xo_ssize_t
305xo_open_list_h (xo_handle_t *xop, const char *name);
306
307xo_ssize_t
308xo_open_list (const char *name);
309
310xo_ssize_t
311xo_open_list_hd (xo_handle_t *xop, const char *name);
312
313xo_ssize_t
314xo_open_list_d (const char *name);
315
316xo_ssize_t
317xo_close_list_h (xo_handle_t *xop, const char *name);
318
319xo_ssize_t
320xo_close_list (const char *name);
321
322xo_ssize_t
323xo_close_list_hd (xo_handle_t *xop);
324
325xo_ssize_t
326xo_close_list_d (void);
327
328xo_ssize_t
329xo_open_instance_h (xo_handle_t *xop, const char *name);
330
331xo_ssize_t
332xo_open_instance (const char *name);
333
334xo_ssize_t
335xo_open_instance_hd (xo_handle_t *xop, const char *name);
336
337xo_ssize_t
338xo_open_instance_d (const char *name);
339
340xo_ssize_t
341xo_close_instance_h (xo_handle_t *xop, const char *name);
342
343xo_ssize_t
344xo_close_instance (const char *name);
345
346xo_ssize_t
347xo_close_instance_hd (xo_handle_t *xop);
348
349xo_ssize_t
350xo_close_instance_d (void);
351
352xo_ssize_t
353xo_open_marker_h (xo_handle_t *xop, const char *name);
354
355xo_ssize_t
356xo_open_marker (const char *name);
357
358xo_ssize_t
359xo_close_marker_h (xo_handle_t *xop, const char *name);
360
361xo_ssize_t
362xo_close_marker (const char *name);
363
364xo_ssize_t
365xo_attr_h (xo_handle_t *xop, const char *name, const char *fmt, ...);
366
367xo_ssize_t
368xo_attr_hv (xo_handle_t *xop, const char *name, const char *fmt, va_list vap);
369
370xo_ssize_t
371xo_attr (const char *name, const char *fmt, ...);
372
373void
374xo_error_hv (xo_handle_t *xop, const char *fmt, va_list vap);
375
376void
377xo_error_h (xo_handle_t *xop, const char *fmt, ...);
378
379void
380xo_error (const char *fmt, ...);
381
382xo_ssize_t
383xo_flush_h (xo_handle_t *xop);
384
385xo_ssize_t
386xo_flush (void);
387
388xo_ssize_t
389xo_finish_h (xo_handle_t *xop);
390
391xo_ssize_t
392xo_finish (void);
393
394void
395xo_finish_atexit (void);
396
397void
398xo_set_leading_xpath (xo_handle_t *xop, const char *path);
399
400void
401xo_warn_hc (xo_handle_t *xop, int code, const char *fmt, ...) PRINTFLIKE(3, 4);
402
403void
404xo_warn_c (int code, const char *fmt, ...) PRINTFLIKE(2, 3);
405
406void
407xo_warn (const char *fmt, ...) PRINTFLIKE(1, 2);
408
409void
410xo_warnx (const char *fmt, ...) PRINTFLIKE(1, 2);
411
412void
413xo_err (int eval, const char *fmt, ...) NORETURN PRINTFLIKE(2, 3);
414
415void
416xo_errx (int eval, const char *fmt, ...) NORETURN PRINTFLIKE(2, 3);
417
418void
419xo_errc (int eval, int code, const char *fmt, ...) NORETURN PRINTFLIKE(3, 4);
420
421void
422xo_message_hcv (xo_handle_t *xop, int code, const char *fmt, va_list vap) PRINTFLIKE(3, 0);
423
424void
425xo_message_hc (xo_handle_t *xop, int code, const char *fmt, ...) PRINTFLIKE(3, 4);
426
427void
428xo_message_c (int code, const char *fmt, ...) PRINTFLIKE(2, 3);
429
430void
431xo_message_e (const char *fmt, ...) PRINTFLIKE(1, 2);
432
433void
434xo_message (const char *fmt, ...) PRINTFLIKE(1, 2);
435
436void
437xo_emit_warn_hcv (xo_handle_t *xop, int as_warning, int code,
438		  const char *fmt, va_list vap);
439
440void
441xo_emit_warn_hc (xo_handle_t *xop, int code, const char *fmt, ...);
442
443void
444xo_emit_warn_c (int code, const char *fmt, ...);
445
446void
447xo_emit_warn (const char *fmt, ...);
448
449void
450xo_emit_warnx (const char *fmt, ...);
451
452void
453xo_emit_err (int eval, const char *fmt, ...) NORETURN;
454
455void
456xo_emit_errx (int eval, const char *fmt, ...) NORETURN;
457
458void
459xo_emit_errc (int eval, int code, const char *fmt, ...) NORETURN;
460
461PRINTFLIKE(4, 0)
462static inline void
463xo_emit_warn_hcvp (xo_handle_t *xop, int as_warning, int code,
464		  const char *fmt, va_list vap)
465{
466    xo_emit_warn_hcv(xop, as_warning, code, fmt, vap);
467}
468
469PRINTFLIKE(3, 4)
470static inline void
471xo_emit_warn_hcp (xo_handle_t *xop, int code, const char *fmt, ...)
472{
473    va_list vap;
474    va_start(vap, fmt);
475    xo_emit_warn_hcv(xop, 1, code, fmt, vap);
476    va_end(vap);
477}
478
479PRINTFLIKE(2, 3)
480static inline void
481xo_emit_warn_cp (int code, const char *fmt, ...)
482{
483    va_list vap;
484    va_start(vap, fmt);
485    xo_emit_warn_hcv(NULL, 1, code, fmt, vap);
486    va_end(vap);
487}
488
489PRINTFLIKE(1, 2)
490static inline void
491xo_emit_warn_p (const char *fmt, ...)
492{
493    int code = errno;
494    va_list vap;
495    va_start(vap, fmt);
496    xo_emit_warn_hcv(NULL, 1, code, fmt, vap);
497    va_end(vap);
498}
499
500PRINTFLIKE(1, 2)
501static inline void
502xo_emit_warnx_p (const char *fmt, ...)
503{
504    va_list vap;
505    va_start(vap, fmt);
506    xo_emit_warn_hcv(NULL, 1, -1, fmt, vap);
507    va_end(vap);
508}
509
510NORETURN PRINTFLIKE(2, 3)
511static inline void
512xo_emit_err_p (int eval, const char *fmt, ...)
513{
514    int code = errno;
515    va_list vap;
516    va_start(vap, fmt);
517    xo_emit_warn_hcv(NULL, 0, code, fmt, vap);
518    va_end(vap);
519
520    exit(eval);
521}
522
523PRINTFLIKE(2, 3)
524static inline void
525xo_emit_errx_p (int eval, const char *fmt, ...)
526{
527    va_list vap;
528    va_start(vap, fmt);
529    xo_emit_warn_hcv(NULL, 0, -1, fmt, vap);
530    va_end(vap);
531    exit(eval);
532}
533
534PRINTFLIKE(3, 4)
535static inline void
536xo_emit_errc_p (int eval, int code, const char *fmt, ...)
537{
538    va_list vap;
539    va_start(vap, fmt);
540    xo_emit_warn_hcv(NULL, 0, code, fmt, vap);
541    va_end(vap);
542    exit(eval);
543}
544
545void
546xo_emit_err_v (int eval, int code, const char *fmt, va_list vap) NORETURN PRINTFLIKE(3, 0);
547
548void
549xo_no_setlocale (void);
550
551/**
552 * @brief Lift libxo-specific arguments from a set of arguments
553 *
554 * libxo-enable programs typically use command line options to enable
555 * all the nifty-cool libxo features.  xo_parse_args() makes this simple
556 * by pre-processing the command line arguments given to main(), handling
557 * and removing the libxo-specific ones, meaning anything starting with
558 * "--libxo".  A full description of these arguments is in the base
559 * documentation.
560 * @param[in] argc Number of arguments (ala #main())
561 * @param[in] argc Array of argument strings (ala #main())
562 * @return New number of arguments, or -1 for failure.
563 */
564int
565xo_parse_args (int argc, char **argv);
566
567/**
568 * This is the "magic" number returned by libxo-supporting commands
569 * when passed the equally magic "--libxo-check" option.  If you
570 * return this, we can (unsafely) assume that since you know the magic
571 * handshake, you'll happily handle future --libxo options and not do
572 * something violent like reboot the box or create another hole in the
573 * ozone layer.
574 */
575#define XO_HAS_LIBXO	121
576
577/**
578 * externs for libxo's version number strings
579 */
580extern const char xo_version[];	      /** Base version triple string */
581extern const char xo_version_extra[]; /** Extra version magic content */
582
583/**
584 * @brief Dump the internal stack of a libxo handle.
585 *
586 * This diagnostic function is something I will ask you to call from
587 * your program when you write to tell me libxo has gone bat-stink
588 * crazy and has discarded your list or container or content.  Output
589 * content will be what we lovingly call "developer entertainment".
590 * @param[in] xop A valid libxo handle, or NULL for the default handle
591 */
592void
593xo_dump_stack (xo_handle_t *xop);
594
595/**
596 * @brief Recode the name of the program, suitable for error output.
597 *
598 * libxo will record the given name for use while generating error
599 * messages.  The contents are not copied, so the value must continue
600 * to point to a valid memory location.  This allows the caller to change
601 * the value, but requires the caller to manage the memory.  Typically
602 * this is called with argv[0] from main().
603 * @param[in] name The name of the current application program
604 */
605void
606xo_set_program (const char *name);
607
608/**
609 * @brief Add a version string to the output, where possible.
610 *
611 * Adds a version number to the output, suitable for tracking
612 * changes in the content.  This is only important for the "encoding"
613 * format styles (XML and JSON) and allows a user of the data to
614 * discern which version of the data model is in use.
615 * @param[in] version The version number, encoded as a string
616 */
617void
618xo_set_version (const char *version);
619
620/**
621 * #xo_set_version with a handle.
622 * @param[in] xop A valid libxo handle, or NULL for the default handle
623 * @param[in] version The version number, encoded as a string
624 */
625void
626xo_set_version_h (xo_handle_t *xop, const char *version);
627
628void
629xo_open_log (const char *ident, int logopt, int facility);
630
631void
632xo_close_log (void);
633
634int
635xo_set_logmask (int maskpri);
636
637void
638xo_set_unit_test_mode (int value);
639
640void
641xo_syslog (int priority, const char *name, const char *message, ...);
642
643void
644xo_vsyslog (int priority, const char *name, const char *message, va_list args);
645
646typedef void (*xo_syslog_open_t)(void);
647typedef void (*xo_syslog_send_t)(const char *full_msg,
648				 const char *v0_hdr, const char *text_only);
649typedef void (*xo_syslog_close_t)(void);
650
651void
652xo_set_syslog_handler (xo_syslog_open_t open_func, xo_syslog_send_t send_func,
653		       xo_syslog_close_t close_func);
654
655void
656xo_set_syslog_enterprise_id (unsigned short eid);
657
658typedef void (*xo_simplify_field_func_t)(const char *, unsigned, int);
659
660char *
661xo_simplify_format (xo_handle_t *xop, const char *fmt, int with_numbers,
662		    xo_simplify_field_func_t field_cb);
663
664xo_ssize_t
665xo_emit_field_hv (xo_handle_t *xop, const char *rolmod, const char *contents,
666		  const char *fmt, const char *efmt,
667		  va_list vap);
668
669xo_ssize_t
670xo_emit_field_h (xo_handle_t *xop, const char *rolmod, const char *contents,
671		 const char *fmt, const char *efmt, ...);
672
673xo_ssize_t
674xo_emit_field (const char *rolmod, const char *contents,
675	       const char *fmt, const char *efmt, ...);
676
677void
678xo_retain_clear_all (void);
679
680void
681xo_retain_clear (const char *fmt);
682
683#endif /* INCLUDE_XO_H */
684