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Diffstat (limited to '')
| -rw-r--r-- | lib/debug.h | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/lib/debug.h b/lib/debug.h new file mode 100644 index 0000000..e9d8a31 --- /dev/null +++ b/lib/debug.h @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Debugging utilities. + * Copyright (C) 2018 Cumulus Networks, Inc. + * Quentin Young + */ +#ifndef _FRRDEBUG_H +#define _FRRDEBUG_H + +#include <zebra.h> +#include "command.h" +#include "frratomic.h" + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * Debugging modes. + * + * FRR's convention is that a debug statement issued under the vty CONFIG_NODE + * persists to the config file, whereas the same debug statement issued from + * the ENABLE_NODE only persists for the current session. These are mapped to + * DEBUG_MODE_CONF and DEBUG_MODE_TERM respectively. + * + * They are not mutually exclusive and are placed in the MSB of the flags + * field in a debugging record. + */ +#define DEBUG_MODE_TERM 0x01000000 +#define DEBUG_MODE_CONF 0x02000000 +#define DEBUG_MODE_ALL (DEBUG_MODE_TERM | DEBUG_MODE_CONF) +#define DEBUG_MODE_NONE 0x00000000 +#define DEBUG_OPT_ALL 0x00FFFFFF +#define DEBUG_OPT_NONE 0x00000000 + + +/* + * Debugging record. + * + * All operations on this record exposed in this header are MT-safe. + * + * flags + * A bitfield with the following format (bytes high to low) + * - [0] Debugging mode field (MSB) | Mode + * - [1] Arbitrary flag field | Option + * - [2] Arbitrary flag field | Option + * - [3] Arbitrary flag field (LSB) | Option + * + * ALL THESE BYTES ARE YOURS - EXCEPT MODE. + * ATTEMPT NO BIT OPS THERE. + * + * The MSB of this field determines the debug mode, Use the DEBUG_MODE* + * macros to manipulate this byte. + * + * The low 3 bytes of this field may be used to store arbitrary information. + * Usually they are used to store flags that tune how detailed the logging + * for a particular debug record is. Use the DEBUG_OPT* macros to manipulate + * those bytes. + * + * All operations performed on this field should be done using the macros + * later in this header file. They are guaranteed to be atomic operations + * with respect to this field. Using anything except the macros to + * manipulate the flags field in a multithreaded environment results in + * undefined behavior. + * + * desc + * Human-readable description of this debugging record. + */ +struct debug { + atomic_uint_fast32_t flags; + const char *desc; +}; + +PREDECL_LIST(debug_cb_list); +/* + * Callback set for debugging code. + * + * debug_set_all + * Function pointer to call when the user requests that all debugs have a + * mode set. + */ +struct debug_callbacks { + /* + * Linked list of Callbacks to call + */ + struct debug_cb_list_item item; + + /* + * flags + * flags to set on debug flag fields + * + * set + * true: set flags + * false: unset flags + */ + void (*debug_set_all)(uint32_t flags, bool set); +}; + +/* + * Check if a mode is set for a debug. + * + * MT-Safe + */ +#define DEBUG_MODE_CHECK(name, mode) \ + CHECK_FLAG_ATOMIC(&(name)->flags, (mode)&DEBUG_MODE_ALL) + +/* + * Check if an option bit is set for a debug. + * + * MT-Safe + */ +#define DEBUG_OPT_CHECK(name, opt) \ + CHECK_FLAG_ATOMIC(&(name)->flags, (opt)&DEBUG_OPT_ALL) + +/* + * Check if bits are set for a debug. + * + * MT-Safe + */ +#define DEBUG_FLAGS_CHECK(name, fl) CHECK_FLAG_ATOMIC(&(name)->flags, (fl)) + +/* + * Set modes on a debug. + * + * MT-Safe + */ +#define DEBUG_MODE_SET(name, mode, onoff) \ + do { \ + if (onoff) \ + SET_FLAG_ATOMIC(&(name)->flags, \ + (mode)&DEBUG_MODE_ALL); \ + else \ + UNSET_FLAG_ATOMIC(&(name)->flags, \ + (mode)&DEBUG_MODE_ALL); \ + } while (0) + +/* Convenience macros for specific set operations. */ +#define DEBUG_MODE_ON(name, mode) DEBUG_MODE_SET(name, mode, true) +#define DEBUG_MODE_OFF(name, mode) DEBUG_MODE_SET(name, mode, false) + +/* + * Set options on a debug. + * + * MT-Safe + */ +#define DEBUG_OPT_SET(name, opt, onoff) \ + do { \ + if (onoff) \ + SET_FLAG_ATOMIC(&(name)->flags, (opt)&DEBUG_OPT_ALL); \ + else \ + UNSET_FLAG_ATOMIC(&(name)->flags, \ + (opt)&DEBUG_OPT_ALL); \ + } while (0) + +/* Convenience macros for specific set operations. */ +#define DEBUG_OPT_ON(name, opt) DEBUG_OPT_SET(name, opt, true) +#define DEBUG_OPT_OFF(name, opt) DEBUG_OPT_SET(name, opt, true) + +/* + * Set bits on a debug. + * + * MT-Safe + */ +#define DEBUG_FLAGS_SET(name, fl, onoff) \ + do { \ + if (onoff) \ + SET_FLAG_ATOMIC(&(name)->flags, (fl)); \ + else \ + UNSET_FLAG_ATOMIC(&(name)->flags, (fl)); \ + } while (0) + +/* Convenience macros for specific set operations. */ +#define DEBUG_FLAGS_ON(name, fl) DEBUG_FLAGS_SET(&(name)->flags, (type), true) +#define DEBUG_FLAGS_OFF(name, fl) DEBUG_FLAGS_SET(&(name)->flags, (type), false) + +/* + * Unset all modes and options on a debug. + * + * MT-Safe + */ +#define DEBUG_CLEAR(name) RESET_FLAG_ATOMIC(&(name)->flags) + +/* + * Set all modes and options on a debug. + * + * MT-Safe + */ +#define DEBUG_ON(name) \ + SET_FLAG_ATOMIC(&(name)->flags, DEBUG_MODE_ALL | DEBUG_OPT_ALL) + +/* + * Map a vty node to the correct debugging mode flags. FRR behaves such that a + * debug statement issued under the config node persists to the config file, + * whereas the same debug statement issued from the enable node only persists + * for the current session. + * + * MT-Safe + */ +#define DEBUG_NODE2MODE(vtynode) \ + (((vtynode) == CONFIG_NODE) ? DEBUG_MODE_ALL : DEBUG_MODE_TERM) + +/* + * Debug at the given level to the default logging destination. + * + * MT-Safe + */ +#define DEBUG(level, name, fmt, ...) \ + do { \ + if (DEBUG_MODE_CHECK(name, DEBUG_MODE_ALL)) \ + zlog_##level(fmt, ##__VA_ARGS__); \ + } while (0) + +/* Convenience macros for the various levels. */ +#define DEBUGE(name, fmt, ...) DEBUG(err, name, fmt, ##__VA_ARGS__) +#define DEBUGW(name, fmt, ...) DEBUG(warn, name, fmt, ##__VA_ARGS__) +#define DEBUGI(name, fmt, ...) DEBUG(info, name, fmt, ##__VA_ARGS__) +#define DEBUGN(name, fmt, ...) DEBUG(notice, name, fmt, ##__VA_ARGS__) +#define DEBUGD(name, fmt, ...) DEBUG(debug, name, fmt, ##__VA_ARGS__) + +/* + * Optional initializer for debugging. Highly recommended. + * + * This function installs common debugging commands and allows the caller to + * specify callbacks to take when these commands are issued, allowing the + * caller to respond to events such as a request to turn off all debugs. + * + * MT-Safe + */ +void debug_init(struct debug_callbacks *cb); + +/* + * Turn on the cli to turn on/off debugs. + * Should only be called by libfrr + */ +void debug_init_cli(void); + +#ifdef __cplusplus +} +#endif + +#endif /* _FRRDEBUG_H */ |