include/asl.h

   1 /*
   2  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 2004 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24
  25 #ifndef __ASL_H__
  26 #define __ASL_H__
  27
  28 #include <stdint.h>
  29 #include <stdarg.h>
  30 #include <sys/cdefs.h>
  31
  32 typedef struct __aslclient *aslclient;
  33 typedef struct __aslmsg *aslmsg;
  34 typedef struct __aslresponse *aslresponse;
  35
  36 /*
  37  * Log levels of the message
  38  */
  39 #define ASL_LEVEL_EMERG   0
  40 #define ASL_LEVEL_ALERT   1
  41 #define ASL_LEVEL_CRIT    2
  42 #define ASL_LEVEL_ERR     3
  43 #define ASL_LEVEL_WARNING 4
  44 #define ASL_LEVEL_NOTICE  5
  45 #define ASL_LEVEL_INFO    6
  46 #define ASL_LEVEL_DEBUG   7
  47
  48 /*
  49  * Corresponding level strings
  50  */
  51 #define ASL_STRING_EMERG        "Emergency"
  52 #define ASL_STRING_ALERT        "Alert"
  53 #define ASL_STRING_CRIT         "Critical"
  54 #define ASL_STRING_ERR          "Error"
  55 #define ASL_STRING_WARNING  "Warning"
  56 #define ASL_STRING_NOTICE   "Notice"
  57 #define ASL_STRING_INFO         "Info"
  58 #define ASL_STRING_DEBUG        "Debug"
  59
  60 /*
  61  * Attribute value comparison operations
  62  */
  63 #define ASL_QUERY_OP_CASEFOLD      0x0010
  64 #define ASL_QUERY_OP_PREFIX                0x0020
  65 #define ASL_QUERY_OP_SUFFIX                0x0040
  66 #define ASL_QUERY_OP_SUBSTRING     0x0060
  67 #define ASL_QUERY_OP_NUMERIC       0x0080
  68 #define ASL_QUERY_OP_REGEX         0x0100
  69
  70 #define ASL_QUERY_OP_EQUAL         0x0001
  71 #define ASL_QUERY_OP_GREATER       0x0002
  72 #define ASL_QUERY_OP_GREATER_EQUAL 0x0003
  73 #define ASL_QUERY_OP_LESS          0x0004
  74 #define ASL_QUERY_OP_LESS_EQUAL    0x0005
  75 #define ASL_QUERY_OP_NOT_EQUAL     0x0006
  76 #define ASL_QUERY_OP_TRUE          0x0007
  77
  78 /*
  79  * Attributes of all messages.
  80  * The following attributes are attached to log messages,
  81  * and are preserved in the order listed.
  82  * Additional attributes may be added as desired, and are
  83  * appended in the order that they are defined.
  84  */
  85 #define ASL_KEY_TIME    "Time"     /* Timestamp (see ctime(3)).  Set automatically */
  86 #define ASL_KEY_HOST    "Host"     /* Sender's address (set by the server) */
  87 #define ASL_KEY_SENDER  "Sender"   /* Sender's identification string.  Default is process name */
  88 #define ASL_KEY_PID     "PID"      /* Sending process ID encoded as a string.  Set automatically */
  89 #define ASL_KEY_UID     "UID"      /* UID that sent the log message (set by the server) */
  90 #define ASL_KEY_GID     "GID"      /* GID that sent the log message (set by the server) */
  91 #define ASL_KEY_LEVEL   "Level"    /* Log level number encoded as a string.  See levels above */
  92 #define ASL_KEY_MSG     "Message"  /* Actual message that will be logged */
  93
  94 /*
  95  * Message Types
  96  */
  97 #define ASL_TYPE_MSG    0
  98 #define ASL_TYPE_QUERY  1
  99
 100 /* Macros to create bitmasks for filter settings - see asl_set_filter */
 101 #define ASL_FILTER_MASK(level) (1 << (level))
 102 #define ASL_FILTER_MASK_UPTO(level) ((1 << ((level) + 1)) - 1)
 103
 104 /* Individual filter masks */
 105 #define ASL_FILTER_MASK_EMERG   0x01
 106 #define ASL_FILTER_MASK_ALERT   0x02
 107 #define ASL_FILTER_MASK_CRIT    0x04
 108 #define ASL_FILTER_MASK_ERR     0x08
 109 #define ASL_FILTER_MASK_WARNING 0x10
 110 #define ASL_FILTER_MASK_NOTICE  0x20
 111 #define ASL_FILTER_MASK_INFO    0x40
 112 #define ASL_FILTER_MASK_DEBUG   0x80
 113
 114 /* Options to asl_open */
 115 #define ASL_OPT_STDERR          0x00000001
 116 #define ASL_OPT_NO_DELAY    0x00000002
 117 #define ASL_OPT_NO_REMOTE   0x00000004
 118
 119 __BEGIN_DECLS
 120
 121 /*
 122  * asl_open: initialize a syslog connection
 123  * This call is optional in most cases.  The library will perform any
 124  * necessary initializations on the fly.  A call to asl_open() is required
 125  * if optional settings must be made before messages are sent to the server.
 126  * These include setting the client filter and managing additional output
 127  * file descriptors.  Note that the default setting of the client filter is
 128  * ASL_FILTER_MASK_UPTO(ASL_LEVEL_NOTICE), so ASL_LEVEL_DEBUG and ASL_LEVEL_INFO
 129  * messages are not sent to the server by default.
 130  *
 131  * Options (defined above) may be set using the opts parameter. They are:
 132  *   ASL_OPT_STDERR    - adds stderr as an output file descriptor
 133  *   ASL_OPT_NO_DELAY  - connects to the server immediately
 134  *   ASL_OPT_NO_REMOTE - disables the remote-control mechanism for adjusting
 135  *                       filter levers for processes using e.g. syslog -c ...
 136  */
 137 aslclient asl_open(const char *ident, const char *facility, uint32_t opts);
 138
 139 /*
 140  * Shuts down the current connection to the server.
 141  */
 142 void asl_close(aslclient asl);
 143
 144 /*
 145  * asl_add_file: write log messages to the given file descriptor
 146  * Log messages will be written to this file as well as to the server.
 147  */
 148 int asl_add_log_file(aslclient asl, int fd);
 149
 150 /*
 151  * asl_remove_file: stop writing log messages to the given file descriptor
 152  * The file descripter is not closed by this routine.
 153  */
 154 int asl_remove_log_file(aslclient asl, int fd);
 155
 156 /*
 157  * Set a filter for messages being sent to the server
 158  * The filter is a bitmask representing priorities.  The ASL_FILTER_MASK
 159  * macro may be used to convert a priority level into a bitmask for that
 160  * level.  The ASL_FILTER_MASK_UPTO macro creates a bitmask for all
 161  * priorities up to and including a given priority.
 162  * Messages with priority levels that do not have a corresponding bit
 163  * set in the filter are not sent to the server, although they will be
 164  * sent to any file descripters added with asl_add_log_file().
 165  * The default setting is ASL_FILTER_MASK_UPTO(ASL_LEVEL_NOTICE).
 166  */
 167 int asl_set_filter(aslclient asl, int f);
 168
 169 /*
 170  * asl_key: examine attribute keys
 171  * returns the key of the nth attribute in a message (beginning at zero)
 172  * returns NULL if the message has fewer attributes
 173  */
 174 const char *asl_key(aslmsg msg, uint32_t n);
 175
 176 /*
 177  * asl_new: create a new log message.
 178  */
 179 aslmsg asl_new(uint32_t type);
 180
 181 /*
 182  * asl_set: set attributes of a message
 183  * msg:  an aslmsg
 184  * key:  attribute key
 185  * value:  attribute value
 186  * returns 0 for success, non-zero for failure
 187  */
 188 int asl_set(aslmsg msg, const char *key, const char *value);
 189
 190 /*
 191  * asl_unset: remove attributes of a message
 192  * msg:  an aslmsg
 193  * key:  attribute key
 194  * returns 0 for success, non-zero for failure
 195  */
 196 int asl_unset(aslmsg msg, const char *key);
 197
 198 /*
 199  * asl_get: get attribute values from a message
 200  * msg:  an aslmsg
 201  * key:  attribute key
 202  * returns the attribute value
 203  * returns NULL if the message does not contain the key
 204  */
 205 const char *asl_get(aslmsg msg, const char *key);
 206
 207 /*
 208  * asl_log: log a message with a particular log level
 209  * msg:  an aslmsg
 210  *       msg may be NULL, in which case a new message will be
 211  *       created and sent using default attributes.
 212  * level: the log level
 213  * format: A formating string followed by a list of arguments, like printf()
 214  * returns 0 for success, non-zero for failure
 215  */
 216 #ifdef __DARWIN_LDBL_COMPAT
 217 int asl_log(aslclient asl, aslmsg msg, int level, const char *format, ...) __DARWIN_LDBL_COMPAT(asl_log);
 218 #else
 219 int asl_log(aslclient asl, aslmsg msg, int level, const char *format, ...);
 220 #endif
 221
 222 /*
 223  * asl_vlog: Similar to asl_log, but taking a va_list instead of a list of
 224  * arguments.
 225  * msg:  an aslmsg
 226  *       msg may be NULL, in which case a new message will be
 227  *       created and sent using default attributes.
 228  * level: the log level of the associated message
 229  * format: A formating string followed by a list of arguments, like vprintf()
 230  * returns 0 for success, non-zero for failure
 231  */
 232 #ifdef __DARWIN_LDBL_COMPAT
 233 int asl_vlog(aslclient asl, aslmsg msg, int level, const char *format, va_list ap) __DARWIN_LDBL_COMPAT(asl_vlog);
 234 #else
 235 int asl_vlog(aslclient asl, aslmsg msg, int level, const char *format, va_list ap);
 236 #endif
 237
 238 /*
 239  * asl_send: send a message
 240  * This routine may be used instead of asl_log() or asl_vlog() if asl_set()
 241  * has been used to set all of a message's attributes.
 242  * msg:  an aslmsg
 243  * returns 0 for success, non-zero for failure
 244  */
 245 int asl_send(aslclient asl, aslmsg msg);
 246
 247 /*
 248  * asl_free: free a message
 249  * msg:  an aslmsg to free
 250  */
 251 void asl_free(aslmsg msg);
 252
 253 /*
 254  * asl_set_query: set arbitrary parameters of a query
 255  * Similar to als_set, but allows richer query operations.
 256  * See ASL_QUERY_OP_* above.
 257  * msg:  an aslmsg
 258  * key:  attribute key
 259  * value:  attribute value
 260  * op:  an operation from the set above.
 261  * returns 0 for success, non-zero for failure
 262  */
 263 int asl_set_query(aslmsg msg, const char *key, const char *value, uint32_t op);
 264
 265 /*
 266  * asl_search: Search for messages matching the criteria described
 267  * by the aslmsg .  The caller should set the attributes to match using
 268  * asl_set_query() or asl_set().  The operatoin ASL_QUERY_OP_EQUAL is
 269  * used for attributes set with asl_set().
 270  * a:  an aslmsg
 271  * returns: a set of messages that can be iterated over using aslresp_next(),
 272  * and the values can be retrieved using aslresp_get.
 273  */
 274 aslresponse asl_search(aslclient asl, aslmsg msg);
 275
 276 /*
 277  * aslresponse_next: Iterate over responses returned from asl_search()
 278  * a: a response returned from asl_search();
 279  * returns: The next log message (an aslmsg) or NULL on failure
 280  */
 281 aslmsg aslresponse_next(aslresponse r);
 282
 283 /*
 284  * aslresponse_free: Free a response returned from asl_search()
 285  * a: a response returned from asl_search()
 286  */
 287 void aslresponse_free(aslresponse a);
 288
 289 __END_DECLS
 290
 291 #endif /* __ASL_H__ */