2 * Copyright (c) 2014-2015, Juniper Networks, Inc.
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
8 * Phil Shafer, July 2014
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.
16 * Full documentation is available in ./doc/libxo.txt or online at:
17 * http://juniper.github.io/libxo/libxo-manual.html
24 #include <sys/types.h>
31 #define NORETURN __dead2
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.
43 #if !defined(NO_PRINTFLIKE)
44 #if defined(__linux) && !defined(__printflike)
45 #define __printflike(_x, _y) __attribute__((__format__ (__printf__, _x, _y)))
47 #define PRINTFLIKE(_x, _y) __printflike(_x, _y)
49 #define PRINTFLIKE(_x, _y)
50 #endif /* NO_PRINTFLIKE */
52 /** Formatting types */
53 typedef 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 */
61 /** Flags for libxo */
62 typedef 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 */
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) */
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 */
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 */
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 */
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 */
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 */
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 */
104 #define XOF_COLOR_MAP XOF_BIT(32) /** Color map has been initialized */
106 typedef unsigned xo_emit_flags_t; /* Flags to xo_emit() and friends */
107 #define XOEF_RETAIN (1<<0) /* Retain parsed formatting information */
110 * The xo_info_t structure provides a mapping between names and
111 * additional data emitted via HTML.
113 typedef 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 */
119 #define XO_INFO_NULL NULL, NULL, NULL /* Use '{ XO_INFO_NULL }' to end lists */
121 struct xo_handle_s; /* Opaque structure forward */
122 typedef struct xo_handle_s xo_handle_t; /* Handle for XO output */
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
129 #ifdef USE_INT_RETURN_CODES
130 typedef int xo_ssize_t; /* Buffer size */
131 #else /* USE_INT_RETURN_CODES */
132 typedef ssize_t xo_ssize_t; /* Buffer size */
133 #endif /* USE_INT_RETURN_CODES */
135 typedef xo_ssize_t (*xo_write_func_t)(void *, const char *);
136 typedef void (*xo_close_func_t)(void *);
137 typedef int (*xo_flush_func_t)(void *);
138 typedef void *(*xo_realloc_func_t)(void *, size_t);
139 typedef void (*xo_free_func_t)(void *);
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'.
146 typedef xo_ssize_t (*xo_formatter_t)(xo_handle_t *, char *, xo_ssize_t,
147 const char *, va_list);
148 typedef void (*xo_checkpointer_t)(xo_handle_t *, va_list, int);
151 xo_create (xo_style_t style, xo_xof_flags_t flags);
154 xo_create_to_file (FILE *fp, xo_style_t style, xo_xof_flags_t flags);
157 xo_destroy (xo_handle_t *xop);
160 xo_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);
164 xo_set_allocator (xo_realloc_func_t realloc_func, xo_free_func_t free_func);
167 xo_set_style (xo_handle_t *xop, xo_style_t style);
170 xo_get_style (xo_handle_t *xop);
173 xo_set_style_name (xo_handle_t *xop, const char *style);
176 xo_set_options (xo_handle_t *xop, const char *input);
179 xo_get_flags (xo_handle_t *xop);
182 xo_set_flags (xo_handle_t *xop, xo_xof_flags_t flags);
185 xo_clear_flags (xo_handle_t *xop, xo_xof_flags_t flags);
188 xo_set_file_h (xo_handle_t *xop, FILE *fp);
191 xo_set_file (FILE *fp);
194 xo_set_info (xo_handle_t *xop, xo_info_t *infop, int count);
197 xo_set_formatter (xo_handle_t *xop, xo_formatter_t func, xo_checkpointer_t);
200 xo_set_depth (xo_handle_t *xop, int depth);
203 xo_emit_hv (xo_handle_t *xop, const char *fmt, va_list vap);
206 xo_emit_h (xo_handle_t *xop, const char *fmt, ...);
209 xo_emit (const char *fmt, ...);
212 xo_emit_hvf (xo_handle_t *xop, xo_emit_flags_t flags,
213 const char *fmt, va_list vap);
216 xo_emit_hf (xo_handle_t *xop, xo_emit_flags_t flags, const char *fmt, ...);
219 xo_emit_f (xo_emit_flags_t flags, const char *fmt, ...);
223 xo_emit_hvp (xo_handle_t *xop, const char *fmt, va_list vap)
225 return xo_emit_hv(xop, fmt, vap);
230 xo_emit_hp (xo_handle_t *xop, const char *fmt, ...)
234 int rc = xo_emit_hv(xop, fmt, vap);
241 xo_emit_p (const char *fmt, ...)
245 int rc = xo_emit_hv(NULL, fmt, vap);
252 xo_emit_hvfp (xo_handle_t *xop, xo_emit_flags_t flags,
253 const char *fmt, va_list vap)
255 return xo_emit_hvf(xop, flags, fmt, vap);
260 xo_emit_hfp (xo_handle_t *xop, xo_emit_flags_t flags, const char *fmt, ...)
264 int rc = xo_emit_hvf(xop, flags, fmt, vap);
271 xo_emit_fp (xo_emit_flags_t flags, const char *fmt, ...)
275 int rc = xo_emit_hvf(NULL, flags, fmt, vap);
281 xo_open_container_h (xo_handle_t *xop, const char *name);
284 xo_open_container (const char *name);
287 xo_open_container_hd (xo_handle_t *xop, const char *name);
290 xo_open_container_d (const char *name);
293 xo_close_container_h (xo_handle_t *xop, const char *name);
296 xo_close_container (const char *name);
299 xo_close_container_hd (xo_handle_t *xop);
302 xo_close_container_d (void);
305 xo_open_list_h (xo_handle_t *xop, const char *name);
308 xo_open_list (const char *name);
311 xo_open_list_hd (xo_handle_t *xop, const char *name);
314 xo_open_list_d (const char *name);
317 xo_close_list_h (xo_handle_t *xop, const char *name);
320 xo_close_list (const char *name);
323 xo_close_list_hd (xo_handle_t *xop);
326 xo_close_list_d (void);
329 xo_open_instance_h (xo_handle_t *xop, const char *name);
332 xo_open_instance (const char *name);
335 xo_open_instance_hd (xo_handle_t *xop, const char *name);
338 xo_open_instance_d (const char *name);
341 xo_close_instance_h (xo_handle_t *xop, const char *name);
344 xo_close_instance (const char *name);
347 xo_close_instance_hd (xo_handle_t *xop);
350 xo_close_instance_d (void);
353 xo_open_marker_h (xo_handle_t *xop, const char *name);
356 xo_open_marker (const char *name);
359 xo_close_marker_h (xo_handle_t *xop, const char *name);
362 xo_close_marker (const char *name);
365 xo_attr_h (xo_handle_t *xop, const char *name, const char *fmt, ...);
368 xo_attr_hv (xo_handle_t *xop, const char *name, const char *fmt, va_list vap);
371 xo_attr (const char *name, const char *fmt, ...);
374 xo_error_hv (xo_handle_t *xop, const char *fmt, va_list vap);
377 xo_error_h (xo_handle_t *xop, const char *fmt, ...);
380 xo_error (const char *fmt, ...);
383 xo_flush_h (xo_handle_t *xop);
389 xo_finish_h (xo_handle_t *xop);
395 xo_finish_atexit (void);
398 xo_set_leading_xpath (xo_handle_t *xop, const char *path);
401 xo_warn_hc (xo_handle_t *xop, int code, const char *fmt, ...) PRINTFLIKE(3, 4);
404 xo_warn_c (int code, const char *fmt, ...) PRINTFLIKE(2, 3);
407 xo_warn (const char *fmt, ...) PRINTFLIKE(1, 2);
410 xo_warnx (const char *fmt, ...) PRINTFLIKE(1, 2);
413 xo_err (int eval, const char *fmt, ...) NORETURN PRINTFLIKE(2, 3);
416 xo_errx (int eval, const char *fmt, ...) NORETURN PRINTFLIKE(2, 3);
419 xo_errc (int eval, int code, const char *fmt, ...) NORETURN PRINTFLIKE(3, 4);
422 xo_message_hcv (xo_handle_t *xop, int code, const char *fmt, va_list vap) PRINTFLIKE(3, 0);
425 xo_message_hc (xo_handle_t *xop, int code, const char *fmt, ...) PRINTFLIKE(3, 4);
428 xo_message_c (int code, const char *fmt, ...) PRINTFLIKE(2, 3);
431 xo_message_e (const char *fmt, ...) PRINTFLIKE(1, 2);
434 xo_message (const char *fmt, ...) PRINTFLIKE(1, 2);
437 xo_emit_warn_hcv (xo_handle_t *xop, int as_warning, int code,
438 const char *fmt, va_list vap);
441 xo_emit_warn_hc (xo_handle_t *xop, int code, const char *fmt, ...);
444 xo_emit_warn_c (int code, const char *fmt, ...);
447 xo_emit_warn (const char *fmt, ...);
450 xo_emit_warnx (const char *fmt, ...);
453 xo_emit_err (int eval, const char *fmt, ...) NORETURN;
456 xo_emit_errx (int eval, const char *fmt, ...) NORETURN;
459 xo_emit_errc (int eval, int code, const char *fmt, ...) NORETURN;
463 xo_emit_warn_hcvp (xo_handle_t *xop, int as_warning, int code,
464 const char *fmt, va_list vap)
466 xo_emit_warn_hcv(xop, as_warning, code, fmt, vap);
471 xo_emit_warn_hcp (xo_handle_t *xop, int code, const char *fmt, ...)
475 xo_emit_warn_hcv(xop, 1, code, fmt, vap);
481 xo_emit_warn_cp (int code, const char *fmt, ...)
485 xo_emit_warn_hcv(NULL, 1, code, fmt, vap);
491 xo_emit_warn_p (const char *fmt, ...)
496 xo_emit_warn_hcv(NULL, 1, code, fmt, vap);
502 xo_emit_warnx_p (const char *fmt, ...)
506 xo_emit_warn_hcv(NULL, 1, -1, fmt, vap);
510 NORETURN PRINTFLIKE(2, 3)
512 xo_emit_err_p (int eval, const char *fmt, ...)
517 xo_emit_warn_hcv(NULL, 0, code, fmt, vap);
525 xo_emit_errx_p (int eval, const char *fmt, ...)
529 xo_emit_warn_hcv(NULL, 0, -1, fmt, vap);
536 xo_emit_errc_p (int eval, int code, const char *fmt, ...)
540 xo_emit_warn_hcv(NULL, 0, code, fmt, vap);
546 xo_emit_err_v (int eval, int code, const char *fmt, va_list vap) NORETURN PRINTFLIKE(3, 0);
549 xo_no_setlocale (void);
552 * @brief Lift libxo-specific arguments from a set of arguments
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
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.
565 xo_parse_args (int argc, char **argv);
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
575 #define XO_HAS_LIBXO 121
578 * externs for libxo's version number strings
580 extern const char xo_version[]; /** Base version triple string */
581 extern const char xo_version_extra[]; /** Extra version magic content */
584 * @brief Dump the internal stack of a libxo handle.
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
593 xo_dump_stack (xo_handle_t *xop);
596 * @brief Recode the name of the program, suitable for error output.
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
606 xo_set_program (const char *name);
609 * @brief Add a version string to the output, where possible.
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
618 xo_set_version (const char *version);
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
626 xo_set_version_h (xo_handle_t *xop, const char *version);
629 xo_open_log (const char *ident, int logopt, int facility);
635 xo_set_logmask (int maskpri);
638 xo_set_unit_test_mode (int value);
641 xo_syslog (int priority, const char *name, const char *message, ...);
644 xo_vsyslog (int priority, const char *name, const char *message, va_list args);
646 typedef void (*xo_syslog_open_t)(void);
647 typedef void (*xo_syslog_send_t)(const char *full_msg,
648 const char *v0_hdr, const char *text_only);
649 typedef void (*xo_syslog_close_t)(void);
652 xo_set_syslog_handler (xo_syslog_open_t open_func, xo_syslog_send_t send_func,
653 xo_syslog_close_t close_func);
656 xo_set_syslog_enterprise_id (unsigned short eid);
658 typedef void (*xo_simplify_field_func_t)(const char *, unsigned, int);
661 xo_simplify_format (xo_handle_t *xop, const char *fmt, int with_numbers,
662 xo_simplify_field_func_t field_cb);
665 xo_emit_field_hv (xo_handle_t *xop, const char *rolmod, const char *contents,
666 const char *fmt, const char *efmt,
670 xo_emit_field_h (xo_handle_t *xop, const char *rolmod, const char *contents,
671 const char *fmt, const char *efmt, ...);
674 xo_emit_field (const char *rolmod, const char *contents,
675 const char *fmt, const char *efmt, ...);
678 xo_retain_clear_all (void);
681 xo_retain_clear (const char *fmt);
683 #endif /* INCLUDE_XO_H */