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'SM_HEAP_CHECK'' ''''

SM_HEAP_CHECK
Memory-leak detection (V8.12 and above) port with confENVDEF

The libsm library in the sendmail source distribution offers a way to provide memory leak detection and error checking that overlays the usual malloc(3), realloc(3), and free(3) C-language library routines. To disable extra checking, define SM_HEAP_CHECK as zero: 

APPENDDEF(`confENVDEF', `-DSM_HEAP_CHECK=0')

If you choose to enable extra checking, it will not be turned on by default. Instead you will need to turn it on and off with special debugging command-line switches (we cover this soon). To enable extra checking, define SM_HEAP_CHECK as 1: 

APPENDDEF(`confENVDEF', `-DSM_HEAP_CHECK=1')

Once extra checking has been included in your sendmail code, you can turn it on and off with debugging command-line switches. The category is sm_check_heap, and there are four meaningful levels: 

# /usr/sbin/sendmail -dsm_check_heap.level ...

The four meaningful values for level are shown in Table 3-12.

Table 3-12. Debugging levels for memory validity checking

Level

Description

1

This level causes a table of all currently allocated blocks to be maintained. The table is used by the sendmail hooks sm_realloc( ) and sm_free( ) to perform validity checks on their first arguments.

2

With this level, a report will be printed just before sendmail exits. That report contains a single line listing the total storage allocation used in bytes.

3

With this level, a report will be printed just before sendmail exits. That report, in addition to the report given previously, will also list all leaked blocks of memory.

4

With this level, a report will be printed just before sendmail exits. That report, in addition to the reports given previously, will also list all allocated memory blocks.

The -dsm_check_heap command-line switch is most useful when porting sendmail to a new machine. It can also be valuable when adding new functions to sendmail or to its companion programs.

To see if this compile-time macro is defined with your sendmail binary, use the -d0.12 debugging command-line switch.



    		Preface
    		Chapter 1. Some Basics
    		Part I: Build and Install
    		Chapter 2. Build and Install sendmail
    		Chapter 3. Tune sendmail with Compile-Time Macros
    		3.1 Before You Begin, a Checklist
    		3.2 To Port, Tune, or Debug
    		3.3 Pitfalls
    		3.4 Compile-Time Macro Reference
    		''AUTO_NIS_ALIASES'' '''
    		''BSD4_3'' '''
    		'BSD4_4'' ''''
    		'DATA_PROGRESS_TIMEOUT'' ''''
    		''DNSMAP'' '''
    		''DSN'' '''
    		''EGD'' '''
    		''ERRLIST_PREDEFINED'' '''
    		''FAST_PID_RECYCLE'' '''
    		'_FFR...'' ''''
    		''FORK'' '''
    		''HAS...'' '''
    		''HESIOD'' '''
    		''HES_GETMAILHOST'' '''
    		''IDENTPROTO'' '''
    		''IP_SRCROUTE'' '''
    		''...IS_BROKEN'' '''
    		'LA_TYPE'' ''''
    		''LDAPMAP'' '''
    		''LOG'' '''
    		''MATCHGECOS'' '''
    		''MAX...'' '''
    		''MEMCHUNKSIZE'' '''
    		''MILTER'' '''
    		''MIME7TO8'' '''
    		''MIME8TO7'' '''
    		''NAMED_BIND'' '''
    		''MAP_NSD'' '''
    		''MAP_REGEX'' '''
    		''NDBM'' '''
    		''NEED...'' '''
    		''NET...'' '''
    		'NETINFO'' ''''
    		''NEWDB'' '''
    		''NIS'' '''
    		''NISPLUS'' '''
    		''NOFTRUNCATE'' '''
    		''NO_GROUP_SET'' '''
    		''NOTUNIX'' '''
    		''_PATH...'' '''
    		''PH_MAP'' '''
    		''PICKY_HELO_CHECK'' '''
    		''PIPELINING'' '''
    		''PSBUFSIZ'' '''
    		''QUEUE'' '''
    		''QUEUESEGSIZE'' '''
    		''REQUIRES_DIR_FSYNC'' '''
    		''SASL'' '''
    		''SCANF'' '''
    		''SECUREWARE'' '''
    		''SFS_TYPE'' '''
    		''SHARE_V1'' '''
    		'SM_...'' ''''
    		'SM_HEAP_CHECK'' ''''
    		'SM_CONF_SHM'' ''''
    		''SMTP'' '''
    		''SMTPDEBUG'' '''
    		''SMTPLINELIM'' '''
    		''SPT_TYPE'' '''
    		''STARTTLS'' '''
    		''SUID_ROOT_FILES_OK'' '''
    		''SYSLOG_BUFSIZE'' '''
    		''SYSTEM5'' '''
    		''TCPWRAPPERS'' '''
    		''TLS_NO_RSA'' '''
    		''TOBUFSIZE'' '''
    		''TTYNAME'' '''
    		''...T'' '''
    		''UDB_DEFAULT_SPEC'' '''
    		''USE_DOUBLE_FORK'' '''
    		''USE_ENVIRON'' '''
    		''USING_NETSCAPE_LDAP'' '''
    		''USERDB'' '''
    		''USESETEUID'' '''
    		''WILDCARD_SHELL'' '''
    		''XDEBUG'' '''
    		Chapter 4. Configure sendmail.cf with m4
    		Chapter 5. Build and Use Companion Programs
    		Part II: Administration
    		Part III: The Configuration File
    		Part IV: Appendixes
    		Bibliography