diff options
| -rw-r--r-- | ChangeLog | 8 | ||||
| -rw-r--r-- | elaborate.cxx | 23 | ||||
| -rw-r--r-- | stap.1.in | 2 | ||||
| -rw-r--r-- | stapprobes.5.in | 3 | ||||
| -rwxr-xr-x | testsuite/semok/twentytwo.stp | 11 |
5 files changed, 33 insertions, 14 deletions
@@ -1,3 +1,11 @@ +2006-06-05 Frank Ch. Eigler <fche@elastic.org> + + PR 2645 cont'd. + * elaborate.cxx (derive_probes): Pass down optional flag + from alias reference to expansion. + * testsuite/semok/twentytwo.stp: Test passing-down. + * stapprobes.5.in: Specify passing-down property of optional flag. + 2006-06-02 Frank Ch. Eigler <fche@elastic.org> PR 2645 cont'd. diff --git a/elaborate.cxx b/elaborate.cxx index e24d26ff..b6d0f226 100644 --- a/elaborate.cxx +++ b/elaborate.cxx @@ -480,28 +480,33 @@ derive_probes (systemtap_session& s, for (unsigned i = 0; i < p->locations.size(); ++i) { probe_point *loc = p->locations[i]; - + + // Pass down optional flag from e.g. alias reference to each + // probe_point instance. We do this by temporarily overriding + // the probe_point optional flag. We could instead deep-copy + // and set a flag on the copy permanently. + + bool old_loc_opt = loc->optional; + loc->optional = loc->optional || optional; + try { unsigned num_atbegin = dps.size(); s.pattern_root->find_and_build (s, p, loc, 0, dps); unsigned num_atend = dps.size(); - if (! optional && ! loc->optional && // something required, but + if (! loc->optional && // something required, but num_atbegin == num_atend) // nothing new derived! throw semantic_error ("no match for probe point"); - - // XXX: perhaps "optional" should operate at the outside - // loop (probe) level. } catch (const semantic_error& e) { // XXX: prefer not to print_error at every nest/unroll level s.print_error (e); cerr << "while: resolving probe point " << *loc << endl; - // if (! exc_outermost) - // throw; } + + loc->optional = old_loc_opt; } } @@ -869,8 +874,8 @@ semantic_pass_symbols (systemtap_session& s) probe* p = dome->probes [i]; vector<derived_probe*> dps; - // much magic happens here: probe alias expansion, - // provider identification + // much magic happens here: probe alias expansion, wildcard + // matching, low-level derived_probe construction. derive_probes (s, p, dps); for (unsigned j=0; j<dps.size(); j++) @@ -410,7 +410,7 @@ at the given point, it just defines a new probe point name as an alias to an existing one. There are two types of alias, i.e. the prologue style and the epilogue style which are identified by "=" and "+=" respectively. - +.PP For prologue style alias, the statement block that follows an alias definition is implicitly added as a prologue to any probe that refers to the alias. While for the epilogue style alias, the statement block diff --git a/stapprobes.5.in b/stapprobes.5.in index f1744d2f..0685ba2d 100644 --- a/stapprobes.5.in +++ b/stapprobes.5.in @@ -28,7 +28,8 @@ identifier may be parametrized by a string or number literal, with a syntax like a function call. A component may include a "*" character, to expand to other matching probe points. A probe point may be followed by a "?" character, to indicate that it is optional, -and that no error should result if it fails to expand. +and that no error should result if it fails to expand. Optionalness +passes down through all levels of alias/wildcard expansion. These are all syntactically valid probe points: .SAMPLE diff --git a/testsuite/semok/twentytwo.stp b/testsuite/semok/twentytwo.stp index f8f44ffb..b5fcb3a0 100755 --- a/testsuite/semok/twentytwo.stp +++ b/testsuite/semok/twentytwo.stp @@ -1,10 +1,15 @@ #! stap -p2 -probe foo.a = kernel.function("no_such_function")?, never { "alias a" } +probe foo.a = kernel.function("no_such_function")?, never { } probe foo.* { } -probe baz.a = kernel.function("no_such_function") { "alias a" } +probe baz.a = kernel.function("no_such_function") { } probe baz.* ? { } -probe bar = kernel.function("no_such_function") { "alias b" } +probe bar = kernel.function("no_such_function") { } probe bar ? { } + +probe bar3 = kernel.function("no_such_function") { } +probe bar2 = bar3 { } +probe bar2 ? { } + |