[mirror_frr.git] / lib / ferr.h

/*
 * Copyright (c) 2015-16  David Lamparter, for NetDEF, Inc.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _FRR_FERR_H
#define _FRR_FERR_H

/***********************************************************
 * scroll down to the end of this file for a full example! *
 ***********************************************************/

#include <stdint.h>
#include <limits.h>
#include <errno.h>

#include "vty.h"

/* return type when this error indication stuff is used.
 *
 * guaranteed to have boolean evaluation to "false" when OK, "true" when error
 * (i.e. can be changed to pointer in the future if neccessary)
 *
 * For checking, always use "if (value)", nothing else.
 * Do _NOT_ use any integer constant (!= 0), or sign check (< 0).
 */
typedef int ferr_r;

/* rough category of error indication */
enum ferr_kind {
	/* no error */
	FERR_OK = 0,

	/* something isn't the way it's supposed to be.
	 * (things that might otherwise be asserts, really)
	 */
	FERR_CODE_BUG,

	/* user-supplied parameters don't make sense or is inconsistent
	 * if you can express a rule for it (e.g. "holdtime > 2 * keepalive"),
	 * it's this category.
	 */
	FERR_CONFIG_INVALID,

	/* user-supplied parameters don't line up with reality
	 * (IP address or interface not available, etc.)
	 * NB: these are really TODOs where the code needs to be fixed to
	 * respond to future changes!
	 */
	FERR_CONFIG_REALITY,

	/* out of some system resource (probably memory)
	 * aka "you didn't spend enough money error" */
	FERR_RESOURCE,

	/* system error (permission denied, etc.) */
	FERR_SYSTEM,

	/* error return from some external library
	 * (FERR_SYSTEM and FERR_LIBRARY are not strongly distinct) */
	FERR_LIBRARY,
};

struct ferr {
	/* code location */
	const char *file;
	const char *func;
	int line;

	enum ferr_kind kind;

	/* unique_id is calculated as a checksum of source filename and error
	 * message format (*before* calling vsnprintf).  Line number and
	 * function name are not used; this keeps the number reasonably static
	 * across changes.
	 */
	uint32_t unique_id;

	char message[384];

	/* valid if != 0.  note "errno" might be preprocessor foobar. */
	int errno_val;
	/* valid if pathname[0] != '\0' */
	char pathname[PATH_MAX];
};

/* Numeric ranges assigned to daemons for use as error codes. */
#define BABEL_FERR_START   0x01000001
#define BABEL_FRRR_END     0x01FFFFFF
#define BGP_FERR_START     0x02000001
#define BGP_FERR_END       0x02FFFFFF
#define EIGRP_FERR_START   0x03000001
#define EIGRP_FERR_END     0x03FFFFFF
#define ISIS_FERR_START    0x04000001
#define ISIS_FERR_END      0x04FFFFFF
#define LDP_FERR_START     0x05000001
#define LDP_FERR_END       0x05FFFFFF
#define LIB_FERR_START     0x06000001
#define LIB_FERR_END       0x06FFFFFF
#define NHRP_FERR_START    0x07000001
#define NHRP_FERR_END      0x07FFFFFF
#define OSPF_FERR_START    0x08000001
#define OSPF_FERR_END      0x08FFFFFF
#define OSPFV3_FERR_START  0x09000001
#define OSPFV3_FERR_END    0x09FFFFFF
#define PBR_FERR_START     0x0A000001
#define PBR_FERR_END       0x0AFFFFFF
#define PIM_FERR_START     0x0B000001
#define PIM_FERR_STOP      0x0BFFFFFF
#define RIP_FERR_START     0x0C000001
#define RIP_FERR_STOP      0x0CFFFFFF
#define RIPNG_FERR_START   0x0D000001
#define RIPNG_FERR_STOP    0x0DFFFFFF
#define SHARP_FERR_START   0x0E000001
#define SHARP_FERR_END     0x0EFFFFFF
#define VTYSH_FERR_START   0x0F000001
#define VTYSH_FRR_END      0x0FFFFFFF
#define WATCHFRR_FRR_START 0x10000001
#define WATCHFRR_FRR_END   0x10FFFFFF
#define ZEBRA_FERR_START   0xF1000001
#define ZEBRA_FERR_END     0xF1FFFFFF
#define END_FERR           0xFFFFFFFF

struct ferr_ref {
	/* Unique error code displayed to end user as a reference. -1 means
	 * this is an uncoded error that does not have reference material. */
	uint32_t code;
	/* Ultra brief title */
	const char *title;
	/* Brief description of error */
	const char *description;
	/* Remedial suggestion */
	const char *suggestion;
};

void ferr_ref_add(struct ferr_ref *ref);
struct ferr_ref *ferr_ref_get(uint32_t code);
void ferr_ref_display(struct vty *, uint32_t code);

/*
 * This function should be called by the
 * code in libfrr.c
 */
void ferr_ref_init(void);
void ferr_ref_fini(void);

/* get error details.
 *
 * NB: errval/ferr_r does NOT carry the full error information.  It's only
 * passed around for future API flexibility.  ferr_get_last always returns
 * the last error set in the current thread.
 */
const struct ferr *ferr_get_last(ferr_r errval);

/* can optionally be called at strategic locations.
 * always returns 0. */
ferr_r ferr_clear(void);

/* do NOT call these functions directly.  only for macro use! */
ferr_r ferr_set_internal(const char *file, int line, const char *func,
			 enum ferr_kind kind, const char *text, ...);
ferr_r ferr_set_internal_ext(const char *file, int line, const char *func,
			     enum ferr_kind kind, const char *pathname,
			     int errno_val, const char *text, ...);

#define ferr_ok() 0

/* Report an error.
 *
 * If you need to do cleanup (free memory, etc.), save the return value in a
 * variable of type ferr_r.
 *
 * Don't put a \n at the end of the error message.
 */
#define ferr_code_bug(...)                                                     \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CODE_BUG,         \
			  __VA_ARGS__)
#define ferr_cfg_invalid(...)                                                  \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_INVALID,   \
			  __VA_ARGS__)
#define ferr_cfg_reality(...)                                                  \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_REALITY,   \
			  __VA_ARGS__)
#define ferr_cfg_resource(...)                                                 \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_RESOURCE,         \
			  __VA_ARGS__)
#define ferr_system(...)                                                       \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_SYSTEM,           \
			  __VA_ARGS__)
#define ferr_library(...)                                                      \
	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_LIBRARY,          \
			  __VA_ARGS__)

/* extended information variants */
#define ferr_system_errno(...)                                                 \
	ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, NULL, \
			      errno, __VA_ARGS__)
#define ferr_system_path_errno(path, ...)                                      \
	ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, path, \
			      errno, __VA_ARGS__)

#include "vty.h"
/* print error message to vty;  $ERR is replaced by the error's message */
void vty_print_error(struct vty *vty, ferr_r err, const char *msg, ...);

#define CMD_FERR_DO(func, action, ...)                                         \
	do {                                                                   \
		ferr_r cmd_retval = func;                                      \
		if (cmd_retval) {                                              \
			vty_print_error(vty, cmd_retval, __VA_ARGS__);         \
			action;                                                \
		}                                                              \
	} while (0)

#define CMD_FERR_RETURN(func, ...)                                             \
	CMD_FERR_DO(func, return CMD_WARNING_CONFIG_FAILED, __VA_ARGS__)
#define CMD_FERR_GOTO(func, label, ...)                                        \
	CMD_FERR_DO(func, goto label, __VA_ARGS__)

/* example: uses bogus #define to keep indent.py happy */
#ifdef THIS_IS_AN_EXAMPLE
ferr_r foo_bar_set(struct object *obj, int bar)
{
	if (bar < 1 || bar >= 100)
		return ferr_config_invalid("bar setting (%d) must be 0<x<100",
					   bar);
	obj->bar = bar;
	if (ioctl(obj->fd, bar))
		return ferr_system_errno("couldn't set bar to %d", bar);

	return ferr_ok();
}

DEFUN("bla")
{
	CMD_FERR_RETURN(foo_bar_set(obj, atoi(argv[1])),
			"command failed: $ERR\n");
	return CMD_SUCCESS;
}

#endif /* THIS_IS_AN_EXAMPLE */

#endif /* _FERR_H */
Commit	Line	Data
3155489a DL	1	/*
	2	* Copyright (c) 2015-16 David Lamparter, for NetDEF, Inc.
	3	*
	4	* Permission to use, copy, modify, and distribute this software for any
	5	* purpose with or without fee is hereby granted, provided that the above
	6	* copyright notice and this permission notice appear in all copies.
	7	*
	8	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	9	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	10	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	11	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	12	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	13	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	14	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	15	*/
	16
	17	#ifndef _FRR_FERR_H
	18	#define _FRR_FERR_H
	19
	20	/***********************************************************
	21	* scroll down to the end of this file for a full example! *
	22	***********************************************************/
	23
	24	#include <stdint.h>
	25	#include <limits.h>
	26	#include <errno.h>
	27
7b526b61 QY	28	#include "vty.h"
7b526b61 QY	29
3155489a DL	30	/* return type when this error indication stuff is used.
	31	*
	32	* guaranteed to have boolean evaluation to "false" when OK, "true" when error
	33	* (i.e. can be changed to pointer in the future if neccessary)
	34	*
	35	* For checking, always use "if (value)", nothing else.
	36	* Do _NOT_ use any integer constant (!= 0), or sign check (< 0).
	37	*/
	38	typedef int ferr_r;
	39
	40	/* rough category of error indication */
	41	enum ferr_kind {
	42	/* no error */
	43	FERR_OK = 0,
	44
	45	/* something isn't the way it's supposed to be.
	46	* (things that might otherwise be asserts, really)
	47	*/
	48	FERR_CODE_BUG,
	49
	50	/* user-supplied parameters don't make sense or is inconsistent
	51	* if you can express a rule for it (e.g. "holdtime > 2 * keepalive"),
	52	* it's this category.
	53	*/
	54	FERR_CONFIG_INVALID,
	55
	56	/* user-supplied parameters don't line up with reality
	57	* (IP address or interface not available, etc.)
	58	* NB: these are really TODOs where the code needs to be fixed to
	59	* respond to future changes!
	60	*/
	61	FERR_CONFIG_REALITY,
	62
	63	/* out of some system resource (probably memory)
	64	* aka "you didn't spend enough money error" */
	65	FERR_RESOURCE,
	66
	67	/* system error (permission denied, etc.) */
	68	FERR_SYSTEM,
	69
	70	/* error return from some external library
	71	* (FERR_SYSTEM and FERR_LIBRARY are not strongly distinct) */
	72	FERR_LIBRARY,
	73	};
	74
	75	struct ferr {
	76	/* code location */
	77	const char *file;
	78	const char *func;
	79	int line;
	80
	81	enum ferr_kind kind;
	82
	83	/* unique_id is calculated as a checksum of source filename and error
	84	* message format (before calling vsnprintf). Line number and
	85	* function name are not used; this keeps the number reasonably static
	86	* across changes.
	87	*/
	88	uint32_t unique_id;
	89
	90	char message[384];
	91
	92	/* valid if != 0. note "errno" might be preprocessor foobar. */
	93	int errno_val;
94	/* valid if pathname[0] != '\0' */
95	char pathname[PATH_MAX];
96	};
97
7b526b61	98	/* Numeric ranges assigned to daemons for use as error codes. */
ad9921db DS	99	#define BABEL_FERR_START 0x01000001
	100	#define BABEL_FRRR_END 0x01FFFFFF
	101	#define BGP_FERR_START 0x02000001
	102	#define BGP_FERR_END 0x02FFFFFF
	103	#define EIGRP_FERR_START 0x03000001
	104	#define EIGRP_FERR_END 0x03FFFFFF
	105	#define ISIS_FERR_START 0x04000001
	106	#define ISIS_FERR_END 0x04FFFFFF
	107	#define LDP_FERR_START 0x05000001
	108	#define LDP_FERR_END 0x05FFFFFF
	109	#define LIB_FERR_START 0x06000001
	110	#define LIB_FERR_END 0x06FFFFFF
	111	#define NHRP_FERR_START 0x07000001
	112	#define NHRP_FERR_END 0x07FFFFFF
	113	#define OSPF_FERR_START 0x08000001
	114	#define OSPF_FERR_END 0x08FFFFFF
	115	#define OSPFV3_FERR_START 0x09000001
	116	#define OSPFV3_FERR_END 0x09FFFFFF
	117	#define PBR_FERR_START 0x0A000001
	118	#define PBR_FERR_END 0x0AFFFFFF
	119	#define PIM_FERR_START 0x0B000001
	120	#define PIM_FERR_STOP 0x0BFFFFFF
	121	#define RIP_FERR_START 0x0C000001
	122	#define RIP_FERR_STOP 0x0CFFFFFF
	123	#define RIPNG_FERR_START 0x0D000001
	124	#define RIPNG_FERR_STOP 0x0DFFFFFF
	125	#define SHARP_FERR_START 0x0E000001
	126	#define SHARP_FERR_END 0x0EFFFFFF
	127	#define VTYSH_FERR_START 0x0F000001
	128	#define VTYSH_FRR_END 0x0FFFFFFF
	129	#define WATCHFRR_FRR_START 0x10000001
	130	#define WATCHFRR_FRR_END 0x10FFFFFF
	131	#define ZEBRA_FERR_START 0xF1000001
	132	#define ZEBRA_FERR_END 0xF1FFFFFF
	133	#define END_FERR 0xFFFFFFFF
7b526b61 QY	134
	135	struct ferr_ref {
	136	/* Unique error code displayed to end user as a reference. -1 means
	137	* this is an uncoded error that does not have reference material. */
	138	uint32_t code;
	139	/* Ultra brief title */
	140	const char *title;
	141	/* Brief description of error */
	142	const char *description;
	143	/* Remedial suggestion */
	144	const char *suggestion;
	145	};
	146
	147	void ferr_ref_add(struct ferr_ref *ref);
	148	struct ferr_ref *ferr_ref_get(uint32_t code);
	149	void ferr_ref_display(struct vty *, uint32_t code);
b66d022e DS	150
	151	/*
	152	* This function should be called by the
	153	* code in libfrr.c
	154	*/
7b526b61 QY	155	void ferr_ref_init(void);
	156	void ferr_ref_fini(void);
	157
3155489a DL	158	/* get error details.
	159	*
	160	* NB: errval/ferr_r does NOT carry the full error information. It's only
	161	* passed around for future API flexibility. ferr_get_last always returns
	162	* the last error set in the current thread.
	163	*/
	164	const struct ferr *ferr_get_last(ferr_r errval);
	165
	166	/* can optionally be called at strategic locations.
	167	* always returns 0. */
	168	ferr_r ferr_clear(void);
	169
	170	/* do NOT call these functions directly. only for macro use! */
	171	ferr_r ferr_set_internal(const char file, int line, const char func,
996c9314	172	enum ferr_kind kind, const char *text, ...);
3155489a	173	ferr_r ferr_set_internal_ext(const char file, int line, const char func,
996c9314 LB	174	enum ferr_kind kind, const char *pathname,
996c9314 LB	175	int errno_val, const char *text, ...);
3155489a	176
996c9314	177	#define ferr_ok() 0
3155489a DL	178
	179	/* Report an error.
	180	*
	181	* If you need to do cleanup (free memory, etc.), save the return value in a
	182	* variable of type ferr_r.
	183	*
	184	* Don't put a \n at the end of the error message.
	185	*/
996c9314 LB	186	#define ferr_code_bug(...) \
	187	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CODE_BUG, \
	188	__VA_ARGS__)
	189	#define ferr_cfg_invalid(...) \
	190	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_INVALID, \
	191	__VA_ARGS__)
	192	#define ferr_cfg_reality(...) \
	193	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_CONFIG_REALITY, \
	194	__VA_ARGS__)
	195	#define ferr_cfg_resource(...) \
	196	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_RESOURCE, \
	197	__VA_ARGS__)
	198	#define ferr_system(...) \
	199	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_SYSTEM, \
	200	__VA_ARGS__)
	201	#define ferr_library(...) \
	202	ferr_set_internal(__FILE__, __LINE__, __func__, FERR_LIBRARY, \
	203	__VA_ARGS__)
3155489a DL	204
3155489a DL	205	/* extended information variants */
996c9314 LB	206	#define ferr_system_errno(...) \
	207	ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, NULL, \
	208	errno, __VA_ARGS__)
	209	#define ferr_system_path_errno(path, ...) \
	210	ferr_set_internal_ext(__FILE__, __LINE__, __func__, FERR_SYSTEM, path, \
	211	errno, __VA_ARGS__)
3155489a DL	212
	213	#include "vty.h"
	214	/* print error message to vty; $ERR is replaced by the error's message */
	215	void vty_print_error(struct vty vty, ferr_r err, const char msg, ...);
	216
996c9314 LB	217	#define CMD_FERR_DO(func, action, ...) \
	218	do { \
	219	ferr_r cmd_retval = func; \
	220	if (cmd_retval) { \
	221	vty_print_error(vty, cmd_retval, __VA_ARGS__); \
	222	action; \
	223	} \
3155489a DL	224	} while (0)
3155489a DL	225
996c9314	226	#define CMD_FERR_RETURN(func, ...) \
7eb09438	227	CMD_FERR_DO(func, return CMD_WARNING_CONFIG_FAILED, __VA_ARGS__)
996c9314	228	#define CMD_FERR_GOTO(func, label, ...) \
3155489a DL	229	CMD_FERR_DO(func, goto label, __VA_ARGS__)
3155489a DL	230
e894f9fd LB	231	/* example: uses bogus #define to keep indent.py happy */
e894f9fd LB	232	#ifdef THIS_IS_AN_EXAMPLE
3155489a DL	233	ferr_r foo_bar_set(struct object *obj, int bar)
	234	{
	235	if (bar < 1 \|\| bar >= 100)
e894f9fd LB	236	return ferr_config_invalid("bar setting (%d) must be 0<x<100",
e894f9fd LB	237	bar);
3155489a	238	obj->bar = bar;
e894f9fd	239	if (ioctl(obj->fd, bar))
3155489a DL	240	return ferr_system_errno("couldn't set bar to %d", bar);
	241
	242	return ferr_ok();
	243	}
	244
	245	DEFUN("bla")
	246	{
	247	CMD_FERR_RETURN(foo_bar_set(obj, atoi(argv[1])),
996c9314	248	"command failed: $ERR\n");
3155489a DL	249	return CMD_SUCCESS;
	250	}
	251
e894f9fd	252	#endif /* THIS_IS_AN_EXAMPLE */
3155489a DL	253
3155489a DL	254	#endif /* _FERR_H */