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Diffstat (limited to 'lib/ferr.h')
| -rw-r--r-- | lib/ferr.h | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/lib/ferr.h b/lib/ferr.h new file mode 100644 index 0000000..c27601f --- /dev/null +++ b/lib/ferr.h @@ -0,0 +1,267 @@ +/* + * 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" + +#ifdef __cplusplus +extern "C" { +#endif + +/* 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 necessary) + * + * 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_FERR_START 0x10000001 +#define WATCHFRR_FERR_END 0x10FFFFFF +#define PATH_FERR_START 0x11000001 +#define PATH_FERR_END 0x11FFFFFF +#define ZEBRA_FERR_START 0xF1000001 +#define ZEBRA_FERR_END 0xF1FFFFFF +#define END_FERR 0xFFFFFFFF + +struct log_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 log_ref_add(struct log_ref *ref); +struct log_ref *log_ref_get(uint32_t code); +void log_ref_display(struct vty *vty, uint32_t code, bool json); + +/* + * This function should be called by the + * code in libfrr.c + */ +void log_ref_init(void); +void log_ref_fini(void); +void log_ref_vty_init(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 */ + +#ifdef __cplusplus +} +#endif + +#endif /* _FERR_H */ |