diff options
Diffstat (limited to 'scripts')
| -rw-r--r-- | scripts/coccinelle/errp-guard.cocci | 336 | ||||
| -rw-r--r-- | scripts/qapi/commands.py | 22 | ||||
| -rw-r--r-- | scripts/qapi/visit.py | 107 |
3 files changed, 388 insertions, 77 deletions
diff --git a/scripts/coccinelle/errp-guard.cocci b/scripts/coccinelle/errp-guard.cocci new file mode 100644 index 0000000000..6e789acf2d --- /dev/null +++ b/scripts/coccinelle/errp-guard.cocci @@ -0,0 +1,336 @@ +// Use ERRP_GUARD() (see include/qapi/error.h) +// +// Copyright (c) 2020 Virtuozzo International GmbH. +// +// This program is free software; you can redistribute it and/or +// modify it under the terms of the GNU General Public License as +// published by the Free Software Foundation; either version 2 of the +// License, or (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program. If not, see +// <http://www.gnu.org/licenses/>. +// +// Usage example: +// spatch --sp-file scripts/coccinelle/errp-guard.cocci \ +// --macro-file scripts/cocci-macro-file.h --in-place \ +// --no-show-diff --max-width 80 FILES... +// +// Note: --max-width 80 is needed because coccinelle default is less +// than 80, and without this parameter coccinelle may reindent some +// lines which fit into 80 characters but not to coccinelle default, +// which in turn produces extra patch hunks for no reason. + +// Switch unusual Error ** parameter names to errp +// (this is necessary to use ERRP_GUARD). +// +// Disable optional_qualifier to skip functions with +// "Error *const *errp" parameter. +// +// Skip functions with "assert(_errp && *_errp)" statement, because +// that signals unusual semantics, and the parameter name may well +// serve a purpose. (like nbd_iter_channel_error()). +// +// Skip util/error.c to not touch, for example, error_propagate() and +// error_propagate_prepend(). +@ depends on !(file in "util/error.c") disable optional_qualifier@ +identifier fn; +identifier _errp != errp; +@@ + + fn(..., +- Error **_errp ++ Error **errp + ,...) + { +( + ... when != assert(_errp && *_errp) +& + <... +- _errp ++ errp + ...> +) + } + +// Add invocation of ERRP_GUARD() to errp-functions where // necessary +// +// Note, that without "when any" the final "..." does not mach +// something matched by previous pattern, i.e. the rule will not match +// double error_prepend in control flow like in +// vfio_set_irq_signaling(). +// +// Note, "exists" says that we want apply rule even if it does not +// match on all possible control flows (otherwise, it will not match +// standard pattern when error_propagate() call is in if branch). +@ disable optional_qualifier exists@ +identifier fn, local_err; +symbol errp; +@@ + + fn(..., Error **errp, ...) + { ++ ERRP_GUARD(); + ... when != ERRP_GUARD(); +( +( + error_append_hint(errp, ...); +| + error_prepend(errp, ...); +| + error_vprepend(errp, ...); +) + ... when any +| + Error *local_err = NULL; + ... +( + error_propagate_prepend(errp, local_err, ...); +| + error_propagate(errp, local_err); +) + ... +) + } + +// Warn when several Error * definitions are in the control flow. +// This rule is not chained to rule1 and less restrictive, to cover more +// functions to warn (even those we are not going to convert). +// +// Note, that even with one (or zero) Error * definition in the each +// control flow we may have several (in total) Error * definitions in +// the function. This case deserves attention too, but I don't see +// simple way to match with help of coccinelle. +@check1 disable optional_qualifier exists@ +identifier fn, _errp, local_err, local_err2; +position p1, p2; +@@ + + fn(..., Error **_errp, ...) + { + ... + Error *local_err = NULL;@p1 + ... when any + Error *local_err2 = NULL;@p2 + ... when any + } + +@ script:python @ +fn << check1.fn; +p1 << check1.p1; +p2 << check1.p2; +@@ + +print('Warning: function {} has several definitions of ' + 'Error * local variable: at {}:{} and then at {}:{}'.format( + fn, p1[0].file, p1[0].line, p2[0].file, p2[0].line)) + +// Warn when several propagations are in the control flow. +@check2 disable optional_qualifier exists@ +identifier fn, _errp; +position p1, p2; +@@ + + fn(..., Error **_errp, ...) + { + ... +( + error_propagate_prepend(_errp, ...);@p1 +| + error_propagate(_errp, ...);@p1 +) + ... +( + error_propagate_prepend(_errp, ...);@p2 +| + error_propagate(_errp, ...);@p2 +) + ... when any + } + +@ script:python @ +fn << check2.fn; +p1 << check2.p1; +p2 << check2.p2; +@@ + +print('Warning: function {} propagates to errp several times in ' + 'one control flow: at {}:{} and then at {}:{}'.format( + fn, p1[0].file, p1[0].line, p2[0].file, p2[0].line)) + +// Match functions with propagation of local error to errp. +// We want to refer these functions in several following rules, but I +// don't know a proper way to inherit a function, not just its name +// (to not match another functions with same name in following rules). +// Not-proper way is as follows: rename errp parameter in functions +// header and match it in following rules. Rename it back after all +// transformations. +// +// The common case is a single definition of local_err with at most one +// error_propagate_prepend() or error_propagate() on each control-flow +// path. Functions with multiple definitions or propagates we want to +// examine manually. Rules check1 and check2 emit warnings to guide us +// to them. +// +// Note that we match not only this "common case", but any function, +// which has the "common case" on at least one control-flow path. +@rule1 disable optional_qualifier exists@ +identifier fn, local_err; +symbol errp; +@@ + + fn(..., Error ** +- errp ++ ____ + , ...) + { + ... + Error *local_err = NULL; + ... +( + error_propagate_prepend(errp, local_err, ...); +| + error_propagate(errp, local_err); +) + ... + } + +// Convert special case with goto separately. +// I tried merging this into the following rule the obvious way, but +// it made Coccinelle hang on block.c +// +// Note interesting thing: if we don't do it here, and try to fixup +// "out: }" things later after all transformations (the rule will be +// the same, just without error_propagate() call), coccinelle fails to +// match this "out: }". +@ disable optional_qualifier@ +identifier rule1.fn, rule1.local_err, out; +symbol errp; +@@ + + fn(..., Error ** ____, ...) + { + <... +- goto out; ++ return; + ...> +- out: +- error_propagate(errp, local_err); + } + +// Convert most of local_err related stuff. +// +// Note, that we inherit rule1.fn and rule1.local_err names, not +// objects themselves. We may match something not related to the +// pattern matched by rule1. For example, local_err may be defined with +// the same name in different blocks inside one function, and in one +// block follow the propagation pattern and in other block doesn't. +// +// Note also that errp-cleaning functions +// error_free_errp +// error_report_errp +// error_reportf_errp +// warn_report_errp +// warn_reportf_errp +// are not yet implemented. They must call corresponding Error* - +// freeing function and then set *errp to NULL, to avoid further +// propagation to original errp (consider ERRP_GUARD in use). +// For example, error_free_errp may look like this: +// +// void error_free_errp(Error **errp) +// { +// error_free(*errp); +// *errp = NULL; +// } +@ disable optional_qualifier exists@ +identifier rule1.fn, rule1.local_err; +expression list args; +symbol errp; +@@ + + fn(..., Error ** ____, ...) + { + <... +( +- Error *local_err = NULL; +| + +// Convert error clearing functions +( +- error_free(local_err); ++ error_free_errp(errp); +| +- error_report_err(local_err); ++ error_report_errp(errp); +| +- error_reportf_err(local_err, args); ++ error_reportf_errp(errp, args); +| +- warn_report_err(local_err); ++ warn_report_errp(errp); +| +- warn_reportf_err(local_err, args); ++ warn_reportf_errp(errp, args); +) +?- local_err = NULL; + +| +- error_propagate_prepend(errp, local_err, args); ++ error_prepend(errp, args); +| +- error_propagate(errp, local_err); +| +- &local_err ++ errp +) + ...> + } + +// Convert remaining local_err usage. For example, different kinds of +// error checking in if conditionals. We can't merge this into +// previous hunk, as this conflicts with other substitutions in it (at +// least with "- local_err = NULL"). +@ disable optional_qualifier@ +identifier rule1.fn, rule1.local_err; +symbol errp; +@@ + + fn(..., Error ** ____, ...) + { + <... +- local_err ++ *errp + ...> + } + +// Always use the same pattern for checking error +@ disable optional_qualifier@ +identifier rule1.fn; +symbol errp; +@@ + + fn(..., Error ** ____, ...) + { + <... +- *errp != NULL ++ *errp + ...> + } + +// Revert temporary ___ identifier. +@ disable optional_qualifier@ +identifier rule1.fn; +@@ + + fn(..., Error ** +- ____ ++ errp + , ...) + { + ... + } diff --git a/scripts/qapi/commands.py b/scripts/qapi/commands.py index 6809b0fb6e..3cf9e1110b 100644 --- a/scripts/qapi/commands.py +++ b/scripts/qapi/commands.py @@ -47,6 +47,7 @@ def gen_call(name, arg_type, boxed, ret_type): ret = mcgen(''' %(lhs)sqmp_%(c_name)s(%(args)s&err); + error_propagate(errp, err); ''', c_name=c_name(name), args=argstr, lhs=lhs) if ret_type: @@ -55,7 +56,7 @@ def gen_call(name, arg_type, boxed, ret_type): goto out; } - qmp_marshal_output_%(c_name)s(retval, ret, &err); + qmp_marshal_output_%(c_name)s(retval, ret, errp); ''', c_name=ret_type.c_name()) return ret @@ -66,15 +67,12 @@ def gen_marshal_output(ret_type): static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp) { - Error *err = NULL; Visitor *v; v = qobject_output_visitor_new(ret_out); - visit_type_%(c_name)s(v, "unused", &ret_in, &err); - if (!err) { + if (visit_type_%(c_name)s(v, "unused", &ret_in, errp)) { visit_complete(v, ret_out); } - error_propagate(errp, err); visit_free(v); v = qapi_dealloc_visitor_new(); visit_type_%(c_name)s(v, "unused", &ret_in, NULL); @@ -104,6 +102,7 @@ def gen_marshal(name, arg_type, boxed, ret_type): %(proto)s { Error *err = NULL; + bool ok = false; Visitor *v; ''', proto=build_marshal_proto(name)) @@ -123,28 +122,26 @@ def gen_marshal(name, arg_type, boxed, ret_type): ret += mcgen(''' v = qobject_input_visitor_new(QOBJECT(args)); - visit_start_struct(v, NULL, NULL, 0, &err); - if (err) { + if (!visit_start_struct(v, NULL, NULL, 0, errp)) { goto out; } ''') if have_args: ret += mcgen(''' - visit_type_%(c_arg_type)s_members(v, &arg, &err); - if (!err) { - visit_check_struct(v, &err); + if (visit_type_%(c_arg_type)s_members(v, &arg, errp)) { + ok = visit_check_struct(v, errp); } ''', c_arg_type=arg_type.c_name()) else: ret += mcgen(''' - visit_check_struct(v, &err); + ok = visit_check_struct(v, errp); ''') ret += mcgen(''' visit_end_struct(v, NULL); - if (err) { + if (!ok) { goto out; } ''') @@ -154,7 +151,6 @@ def gen_marshal(name, arg_type, boxed, ret_type): ret += mcgen(''' out: - error_propagate(errp, err); visit_free(v); ''') diff --git a/scripts/qapi/visit.py b/scripts/qapi/visit.py index d5d7a1031f..3fb2f30510 100644 --- a/scripts/qapi/visit.py +++ b/scripts/qapi/visit.py @@ -23,7 +23,7 @@ def gen_visit_decl(name, scalar=False): if not scalar: c_type += '*' return mcgen(''' -void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error **errp); +bool visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error **errp); ''', c_name=c_name(name), c_type=c_type) @@ -31,7 +31,7 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error ** def gen_visit_members_decl(name): return mcgen(''' -void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp); +bool visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp); ''', c_name=c_name(name)) @@ -39,18 +39,15 @@ void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp); def gen_visit_object_members(name, base, members, variants): ret = mcgen(''' -void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) +bool visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) { - Error *err = NULL; - ''', c_name=c_name(name)) if base: ret += mcgen(''' - visit_type_%(c_type)s_members(v, (%(c_type)s *)obj, &err); - if (err) { - goto out; + if (!visit_type_%(c_type)s_members(v, (%(c_type)s *)obj, errp)) { + return false; } ''', c_type=base.c_name()) @@ -64,9 +61,8 @@ void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) name=memb.name, c_name=c_name(memb.name)) push_indent() ret += mcgen(''' - visit_type_%(c_type)s(v, "%(name)s", &obj->%(c_name)s, &err); - if (err) { - goto out; + if (!visit_type_%(c_type)s(v, "%(name)s", &obj->%(c_name)s, errp)) { + return false; } ''', c_type=memb.type.c_name(), name=memb.name, @@ -99,8 +95,7 @@ void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) else: ret += mcgen(''' case %(case)s: - visit_type_%(c_type)s_members(v, &obj->u.%(c_name)s, &err); - break; + return visit_type_%(c_type)s_members(v, &obj->u.%(c_name)s, errp); ''', case=case_str, c_type=var.type.c_name(), c_name=c_name(var.name)) @@ -112,15 +107,8 @@ void visit_type_%(c_name)s_members(Visitor *v, %(c_name)s *obj, Error **errp) } ''') - # 'goto out' produced for base, for each member, and if variants were - # present - if base or members or variants: - ret += mcgen(''' - -out: -''') ret += mcgen(''' - error_propagate(errp, err); + return true; } ''') return ret @@ -129,35 +117,31 @@ out: def gen_visit_list(name, element_type): return mcgen(''' -void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +bool visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) { - Error *err = NULL; + bool ok = false; %(c_name)s *tail; size_t size = sizeof(**obj); - visit_start_list(v, name, (GenericList **)obj, size, &err); - if (err) { - goto out; + if (!visit_start_list(v, name, (GenericList **)obj, size, errp)) { + return false; } for (tail = *obj; tail; tail = (%(c_name)s *)visit_next_list(v, (GenericList *)tail, size)) { - visit_type_%(c_elt_type)s(v, NULL, &tail->value, &err); - if (err) { - break; + if (!visit_type_%(c_elt_type)s(v, NULL, &tail->value, errp)) { + goto out_obj; } } - if (!err) { - visit_check_list(v, &err); - } + ok = visit_check_list(v, errp); +out_obj: visit_end_list(v, (void **)obj); - if (err && visit_is_input(v)) { + if (!ok && visit_is_input(v)) { qapi_free_%(c_name)s(*obj); *obj = NULL; } -out: - error_propagate(errp, err); + return ok; } ''', c_name=c_name(name), c_elt_type=element_type.c_name()) @@ -166,11 +150,12 @@ out: def gen_visit_enum(name): return mcgen(''' -void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error **errp) +bool visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error **errp) { int value = *obj; - visit_type_enum(v, name, &value, &%(c_name)s_lookup, errp); + bool ok = visit_type_enum(v, name, &value, &%(c_name)s_lookup, errp); *obj = value; + return ok; } ''', c_name=c_name(name)) @@ -179,18 +164,18 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error def gen_visit_alternate(name, variants): ret = mcgen(''' -void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +bool visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) { - Error *err = NULL; + bool ok = false; - visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj), - &err); - if (err) { - goto out; + if (!visit_start_alternate(v, name, (GenericAlternate **)obj, + sizeof(**obj), errp)) { + return false; } if (!*obj) { /* incomplete */ assert(visit_is_dealloc(v)); + ok = true; goto out_obj; } switch ((*obj)->type) { @@ -205,13 +190,11 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error case=var.type.alternate_qtype()) if isinstance(var.type, QAPISchemaObjectType): ret += mcgen(''' - visit_start_struct(v, name, NULL, 0, &err); - if (err) { + if (!visit_start_struct(v, name, NULL, 0, errp)) { break; } - visit_type_%(c_type)s_members(v, &(*obj)->u.%(c_name)s, &err); - if (!err) { - visit_check_struct(v, &err); + if (visit_type_%(c_type)s_members(v, &(*obj)->u.%(c_name)s, errp)) { + ok = visit_check_struct(v, errp); } visit_end_struct(v, NULL); ''', @@ -219,7 +202,7 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error c_name=c_name(var.name)) else: ret += mcgen(''' - visit_type_%(c_type)s(v, name, &(*obj)->u.%(c_name)s, &err); + ok = visit_type_%(c_type)s(v, name, &(*obj)->u.%(c_name)s, errp); ''', c_type=var.type.c_name(), c_name=c_name(var.name)) @@ -233,7 +216,7 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error abort(); default: assert(visit_is_input(v)); - error_setg(&err, QERR_INVALID_PARAMETER_TYPE, name ? name : "null", + error_setg(errp, QERR_INVALID_PARAMETER_TYPE, name ? name : "null", "%(name)s"); /* Avoid passing invalid *obj to qapi_free_%(c_name)s() */ g_free(*obj); @@ -241,12 +224,11 @@ void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error } out_obj: visit_end_alternate(v, (void **)obj); - if (err && visit_is_input(v)) { + if (!ok && visit_is_input(v)) { qapi_free_%(c_name)s(*obj); *obj = NULL; } -out: - error_propagate(errp, err); + return ok; } ''', name=name, c_name=c_name(name)) @@ -257,32 +239,29 @@ out: def gen_visit_object(name, base, members, variants): return mcgen(''' -void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) +bool visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp) { - Error *err = NULL; + bool ok = false; - visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), &err); - if (err) { - goto out; + if (!visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), errp)) { + return false; } if (!*obj) { /* incomplete */ assert(visit_is_dealloc(v)); goto out_obj; } - visit_type_%(c_name)s_members(v, *obj, &err); - if (err) { + if (!visit_type_%(c_name)s_members(v, *obj, errp)) { goto out_obj; } - visit_check_struct(v, &err); + ok = visit_check_struct(v, errp); out_obj: visit_end_struct(v, (void **)obj); - if (err && visit_is_input(v)) { + if (!ok && visit_is_input(v)) { qapi_free_%(c_name)s(*obj); *obj = NULL; } -out: - error_propagate(errp, err); + return ok; } ''', c_name=c_name(name)) |