libvirt/src/internal.h
Daniel P. Berrange ddf3bd32ce Rewrite all the DTrace/SystemTAP probing
The libvirtd daemon had a few crude system tap probes. Some of
these were broken during the RPC rewrite. The new modular RPC
code is structured in a way that allows much more effective
tracing. Instead of trying to hook up the original probes,
define a new set of probes for the RPC and event code.

The master probes file is now src/probes.d.  This contains
probes for virNetServerClientPtr, virNetClientPtr, virSocketPtr
virNetTLSContextPtr and virNetTLSSessionPtr modules. Also add
probes for the poll event loop.

The src/dtrace2systemtap.pl script can convert the probes.d
file into a libvirt_probes.stp file to make use from systemtap
much simpler.

The src/rpc/gensystemtap.pl script can generate a set of
systemtap functions for translating RPC enum values into
printable strings. This works for all RPC header enums (program,
type, status, procedure) and also the authentication enum

The PROBE macro will automatically generate a VIR_DEBUG
statement, so any place with a PROBE can remove any existing
manual DEBUG statements.

* daemon/libvirtd.stp, daemon/probes.d: Remove obsolete probing
* daemon/libvirtd.h: Remove probe macros
* daemon/Makefile.am: Remove all probe buildings/install
* daemon/remote.c: Update authentication probes
* src/dtrace2systemtap.pl, src/rpc/gensystemtap.pl: Scripts
  to generate STP files
* src/internal.h: Add probe macros
* src/probes.d: Master list of probes
* src/rpc/virnetclient.c, src/rpc/virnetserverclient.c,
  src/rpc/virnetsocket.c, src/rpc/virnettlscontext.c,
  src/util/event_poll.c: Insert probe points, removing any
  DEBUG statements that duplicate the info
2011-10-11 11:26:13 +01:00

318 lines
11 KiB
C

/*
* internal.h: internal definitions just used by code from the library
*/
#ifndef __VIR_INTERNAL_H__
# define __VIR_INTERNAL_H__
# include <errno.h>
# include <limits.h>
# include <verify.h>
# include <stdbool.h>
# if STATIC_ANALYSIS
# undef NDEBUG /* Don't let a prior NDEBUG definition cause trouble. */
# include <assert.h>
# define sa_assert(expr) assert (expr)
# else
# define sa_assert(expr) /* empty */
# endif
/* The library itself is allowed to use deprecated functions /
* variables, so effectively undefine the deprecated attribute
* which would otherwise be defined in libvirt.h.
*/
# define VIR_DEPRECATED /*empty*/
/* All uses of _() within the library should pick up translations from
* libvirt's message files, rather than from the package that is
* linking in the library. Setting this macro before including
* "gettext.h" means that gettext() (and _()) will properly expand to
* dgettext. */
# define DEFAULT_TEXT_DOMAIN PACKAGE
# include "gettext.h"
# define _(str) gettext(str)
# define N_(str) str
# include "libvirt/libvirt.h"
# include "libvirt/libvirt-qemu.h"
# include "libvirt/virterror.h"
# include "libvirt_internal.h"
# include "c-strcase.h"
/* On architectures which lack these limits, define them (ie. Cygwin).
* Note that the libvirt code should be robust enough to handle the
* case where actual value is longer than these limits (eg. by setting
* length correctly in second argument to gethostname and by always
* using strncpy instead of strcpy).
*/
# ifndef HOST_NAME_MAX
# define HOST_NAME_MAX 256
# endif
# ifndef IF_NAMESIZE
# define IF_NAMESIZE 16
# endif
# ifndef INET_ADDRSTRLEN
# define INET_ADDRSTRLEN 16
# endif
/* String equality tests, suggested by Jim Meyering. */
# define STREQ(a,b) (strcmp(a,b) == 0)
# define STRCASEEQ(a,b) (c_strcasecmp(a,b) == 0)
# define STRNEQ(a,b) (strcmp(a,b) != 0)
# define STRCASENEQ(a,b) (c_strcasecmp(a,b) != 0)
# define STREQLEN(a,b,n) (strncmp(a,b,n) == 0)
# define STRCASEEQLEN(a,b,n) (c_strncasecmp(a,b,n) == 0)
# define STRNEQLEN(a,b,n) (strncmp(a,b,n) != 0)
# define STRCASENEQLEN(a,b,n) (c_strncasecmp(a,b,n) != 0)
# define STRPREFIX(a,b) (strncmp(a,b,strlen(b)) == 0)
# define STRSKIP(a,b) (STRPREFIX(a,b) ? (a) + strlen(b) : NULL)
# define STREQ_NULLABLE(a, b) \
((!(a) && !(b)) || ((a) && (b) && STREQ((a), (b))))
# define STRNEQ_NULLABLE(a, b) \
((!(a) ^ !(b)) || ((a) && (b) && STRNEQ((a), (b))))
# define NUL_TERMINATE(buf) do { (buf)[sizeof(buf)-1] = '\0'; } while (0)
# define ARRAY_CARDINALITY(Array) (sizeof (Array) / sizeof *(Array))
/* C99 uses __func__. __FUNCTION__ is legacy. */
# ifndef __GNUC__
# define __FUNCTION__ __func__
# endif
# ifdef __GNUC__
# ifndef __GNUC_PREREQ
# if defined __GNUC__ && defined __GNUC_MINOR__
# define __GNUC_PREREQ(maj, min) \
((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
# else
# define __GNUC_PREREQ(maj,min) 0
# endif
/* Work around broken limits.h on debian etch */
# if defined _GCC_LIMITS_H_ && ! defined ULLONG_MAX
# define ULLONG_MAX ULONG_LONG_MAX
# endif
# endif /* __GNUC__ */
/**
* ATTRIBUTE_UNUSED:
*
* Macro to flag conciously unused parameters to functions
*/
# ifndef ATTRIBUTE_UNUSED
# define ATTRIBUTE_UNUSED __attribute__((__unused__))
# endif
/**
* ATTRIBUTE_NORETURN:
*
* Macro to indicate that a function won't return to the caller
*/
# ifndef ATTRIBUTE_NORETURN
# define ATTRIBUTE_NORETURN __attribute__((__noreturn__))
# endif
/**
* ATTRIBUTE_SENTINEL:
*
* Macro to check for NULL-terminated varargs lists
*/
# ifndef ATTRIBUTE_SENTINEL
# if __GNUC_PREREQ (4, 0)
# define ATTRIBUTE_SENTINEL __attribute__((__sentinel__))
# else
# define ATTRIBUTE_SENTINEL
# endif
# endif
/**
* ATTRIBUTE_FMT_PRINTF
*
* Macro used to check printf like functions, if compiling
* with gcc.
*
* We use gnulib which guarantees we always have GNU style
* printf format specifiers even on broken Win32 platforms
* hence we have to force 'gnu_printf' for new GCC
*/
# ifndef ATTRIBUTE_FMT_PRINTF
# if __GNUC_PREREQ (4, 4)
# define ATTRIBUTE_FMT_PRINTF(fmtpos,argpos) __attribute__((__format__ (gnu_printf, fmtpos,argpos)))
# else
# define ATTRIBUTE_FMT_PRINTF(fmtpos,argpos) __attribute__((__format__ (printf, fmtpos,argpos)))
# endif
# endif
# ifndef ATTRIBUTE_RETURN_CHECK
# if __GNUC_PREREQ (3, 4)
# define ATTRIBUTE_RETURN_CHECK __attribute__((__warn_unused_result__))
# else
# define ATTRIBUTE_RETURN_CHECK
# endif
# endif
/**
* ATTRIBUTE_PACKED
*
* force a structure to be packed, i.e. not following architecture and
* compiler best alignments for its sub components. It's needed for example
* for the network filetering code when defining the content of raw
* ethernet packets.
* Others compiler than gcc may use something different e.g. #pragma pack(1)
*/
# ifndef ATTRIBUTE_PACKED
# if __GNUC_PREREQ (3, 3)
# define ATTRIBUTE_PACKED __attribute__((packed))
# else
# error "Need an __attribute__((packed)) equivalent"
# endif
# endif
# ifndef ATTRIBUTE_NONNULL
# if __GNUC_PREREQ (3, 3)
# define ATTRIBUTE_NONNULL(m) __attribute__((__nonnull__(m)))
# else
# define ATTRIBUTE_NONNULL(m)
# endif
# endif
# else
# ifndef ATTRIBUTE_UNUSED
# define ATTRIBUTE_UNUSED
# endif
# ifndef ATTRIBUTE_FMT_PRINTF
# define ATTRIBUTE_FMT_PRINTF(...)
# endif
# ifndef ATTRIBUTE_RETURN_CHECK
# define ATTRIBUTE_RETURN_CHECK
# endif
# endif /* __GNUC__ */
/*
* Use this when passing possibly-NULL strings to printf-a-likes.
*/
# define NULLSTR(s) \
((void)verify_true(sizeof *(s) == sizeof (char)), \
(s) ? (s) : "(null)")
/**
* TODO:
*
* macro to flag unimplemented blocks
*/
# define TODO \
fprintf(stderr, "Unimplemented block at %s:%d\n", \
__FILE__, __LINE__);
/**
* virCheckFlags:
* @supported: an OR'ed set of supported flags
* @retval: return value in case unsupported flags were passed
*
* To avoid memory leaks this macro has to be used before any non-trivial
* code which could possibly allocate some memory.
*
* Returns nothing. Exits the caller function if unsupported flags were
* passed to it.
*/
# define virCheckFlags(supported, retval) \
do { \
unsigned long __unsuppflags = flags & ~(supported); \
if (__unsuppflags) { \
virReportErrorHelper(VIR_FROM_THIS, \
VIR_ERR_INVALID_ARG, \
__FILE__, \
__FUNCTION__, \
__LINE__, \
_("%s: unsupported flags (0x%lx)"), \
__FUNCTION__, __unsuppflags); \
return retval; \
} \
} while (0)
/* divide value by size, rounding up */
# define VIR_DIV_UP(value, size) (((value) + (size) - 1) / (size))
# if WITH_DTRACE
# ifndef LIBVIRT_PROBES_H
# define LIBVIRT_PROBES_H
# include "probes.h"
# endif /* LIBVIRT_PROBES_H */
/* Systemtap 1.2 headers have a bug where they cannot handle a
* variable declared with array type. Work around this by casting all
* arguments. This is some gross use of the preprocessor because
* PROBE is a var-arg macro, but it is better than the alternative of
* making all callers to PROBE have to be aware of the issues. And
* hopefully, if we ever add a call to PROBE with other than 9
* end arguments, you can figure out the pattern to extend this hack.
*/
# define VIR_COUNT_ARGS(...) VIR_ARG11(__VA_ARGS__, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1)
# define VIR_ARG11(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, ...) _11
# define VIR_ADD_CAST_EXPAND(a, b, ...) VIR_ADD_CAST_PASTE(a, b, __VA_ARGS__)
# define VIR_ADD_CAST_PASTE(a, b, ...) a##b(__VA_ARGS__)
/* The double cast is necessary to silence gcc warnings; any pointer
* can safely go to intptr_t and back to void *, which collapses
* arrays into pointers; while any integer can be widened to intptr_t
* then cast to void *. */
# define VIR_ADD_CAST(a) ((void *)(intptr_t)(a))
# define VIR_ADD_CAST1(a) \
VIR_ADD_CAST(a)
# define VIR_ADD_CAST2(a, b) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b)
# define VIR_ADD_CAST3(a, b, c) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c)
# define VIR_ADD_CAST4(a, b, c, d) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d)
# define VIR_ADD_CAST5(a, b, c, d, e) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d), VIR_ADD_CAST(e)
# define VIR_ADD_CAST6(a, b, c, d, e, f) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d), VIR_ADD_CAST(e), VIR_ADD_CAST(f)
# define VIR_ADD_CAST7(a, b, c, d, e, f, g) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d), VIR_ADD_CAST(e), VIR_ADD_CAST(f), \
VIR_ADD_CAST(g)
# define VIR_ADD_CAST8(a, b, c, d, e, f, g, h) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d), VIR_ADD_CAST(e), VIR_ADD_CAST(f), \
VIR_ADD_CAST(g), VIR_ADD_CAST(h)
# define VIR_ADD_CAST9(a, b, c, d, e, f, g, h, i) \
VIR_ADD_CAST(a), VIR_ADD_CAST(b), VIR_ADD_CAST(c), \
VIR_ADD_CAST(d), VIR_ADD_CAST(e), VIR_ADD_CAST(f), \
VIR_ADD_CAST(g), VIR_ADD_CAST(h), VIR_ADD_CAST(i)
# define VIR_ADD_CASTS(...) \
VIR_ADD_CAST_EXPAND(VIR_ADD_CAST, VIR_COUNT_ARGS(__VA_ARGS__), \
__VA_ARGS__)
# define PROBE_EXPAND(NAME, ARGS) NAME(ARGS)
# define PROBE(NAME, FMT, ...) \
VIR_DEBUG_INT("trace." __FILE__ , __func__, __LINE__, \
#NAME ": " FMT, __VA_ARGS__); \
if (LIBVIRT_ ## NAME ## _ENABLED()) { \
PROBE_EXPAND(LIBVIRT_ ## NAME, \
VIR_ADD_CASTS(__VA_ARGS__)); \
}
# else
# define PROBE(NAME, FMT, ...) \
VIR_DEBUG_INT("trace." __FILE__, __func__, __LINE__, \
#NAME ": " FMT, __VA_ARGS__);
# endif
#endif /* __VIR_INTERNAL_H__ */