97 lines
2.7 KiB
Go
97 lines
2.7 KiB
Go
// Copyright 2013 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package oracle
|
|
|
|
import (
|
|
"fmt"
|
|
"go/token"
|
|
|
|
"golang.org/x/tools/go/callgraph"
|
|
"golang.org/x/tools/go/ssa"
|
|
"golang.org/x/tools/oracle/serial"
|
|
)
|
|
|
|
// Callstack displays an arbitrary path from a root of the callgraph
|
|
// to the function at the current position.
|
|
//
|
|
// The information may be misleading in a context-insensitive
|
|
// analysis. e.g. the call path X->Y->Z might be infeasible if Y never
|
|
// calls Z when it is called from X. TODO(adonovan): think about UI.
|
|
//
|
|
// TODO(adonovan): permit user to specify a starting point other than
|
|
// the analysis root.
|
|
//
|
|
func callstack(o *Oracle, qpos *QueryPos) (queryResult, error) {
|
|
pkg := o.prog.Package(qpos.info.Pkg)
|
|
if pkg == nil {
|
|
return nil, fmt.Errorf("no SSA package")
|
|
}
|
|
|
|
if !ssa.HasEnclosingFunction(pkg, qpos.path) {
|
|
return nil, fmt.Errorf("this position is not inside a function")
|
|
}
|
|
|
|
buildSSA(o)
|
|
|
|
target := ssa.EnclosingFunction(pkg, qpos.path)
|
|
if target == nil {
|
|
return nil, fmt.Errorf("no SSA function built for this location (dead code?)")
|
|
}
|
|
|
|
// Run the pointer analysis and build the complete call graph.
|
|
o.ptaConfig.BuildCallGraph = true
|
|
cg := ptrAnalysis(o).CallGraph
|
|
cg.DeleteSyntheticNodes()
|
|
|
|
// Search for an arbitrary path from a root to the target function.
|
|
isEnd := func(n *callgraph.Node) bool { return n.Func == target }
|
|
callpath := callgraph.PathSearch(cg.Root, isEnd)
|
|
if callpath != nil {
|
|
callpath = callpath[1:] // remove synthetic edge from <root>
|
|
}
|
|
|
|
return &callstackResult{
|
|
qpos: qpos,
|
|
target: target,
|
|
callpath: callpath,
|
|
}, nil
|
|
}
|
|
|
|
type callstackResult struct {
|
|
qpos *QueryPos
|
|
target *ssa.Function
|
|
callpath []*callgraph.Edge
|
|
}
|
|
|
|
func (r *callstackResult) display(printf printfFunc) {
|
|
if r.callpath != nil {
|
|
printf(r.qpos, "Found a call path from root to %s", r.target)
|
|
printf(r.target, "%s", r.target)
|
|
for i := len(r.callpath) - 1; i >= 0; i-- {
|
|
edge := r.callpath[i]
|
|
printf(edge, "%s from %s", edge.Description(), edge.Caller.Func)
|
|
}
|
|
} else {
|
|
printf(r.target, "%s is unreachable in this analysis scope", r.target)
|
|
}
|
|
}
|
|
|
|
func (r *callstackResult) toSerial(res *serial.Result, fset *token.FileSet) {
|
|
var callers []serial.Caller
|
|
for i := len(r.callpath) - 1; i >= 0; i-- { // (innermost first)
|
|
edge := r.callpath[i]
|
|
callers = append(callers, serial.Caller{
|
|
Pos: fset.Position(edge.Pos()).String(),
|
|
Caller: edge.Caller.Func.String(),
|
|
Desc: edge.Description(),
|
|
})
|
|
}
|
|
res.Callstack = &serial.CallStack{
|
|
Pos: fset.Position(r.target.Pos()).String(),
|
|
Target: r.target.String(),
|
|
Callers: callers,
|
|
}
|
|
}
|