Register functions from reloc targets

Rizin shows calls to reloc targets as their function names in
disassembly. We do the same in the decompiler.
Addresses #312

Author: thestr4ng3r

src/RizinScope.cpp

@@ -410,6 +410,14 @@ FunctionSymbol *RizinScope::registerFunction(RzAnalysisFunction *fcn) const
 	return dynamic_cast<FunctionSymbol *>(sym);
 }
 
+FunctionSymbol *RizinScope::registerRelocTarget(RzBinReloc *reloc) const
+{
+	RzCoreLock core(arch->getCore());
+	if(!reloc->import || !reloc->import->name)
+		return nullptr;
+	return cache->addFunction(Address(arch->getDefaultCodeSpace(), reloc->target_vaddr), reloc->import->name);
+}
+
 Symbol *RizinScope::registerFlag(RzFlagItem *flag) const
 {
 	RzCoreLock core(arch->getCore());
@@ -516,6 +524,14 @@ Symbol *RizinScope::queryRizinAbsolute(ut64 addr, bool contain) const
 	if(glob)
 		return registerGlobalVar(glob);
 
+	RzBinReloc *reloc = rz_core_get_reloc_to(core, addr);
+	if(reloc && reloc->import)
+	{
+		auto rsym = registerRelocTarget(reloc);
+		if(rsym)
+			return rsym;
+	}
+
 	// TODO: register more things
 
 	// TODO: correctly handle contain for flags

src/RizinScope.h

@@ -19,6 +19,7 @@ class RizinArchitecture;
 typedef struct rz_analysis_function_t RzAnalysisFunction;
 typedef struct rz_flag_item_t RzFlagItem;
 typedef struct rz_analysis_var_global_t RzAnalysisVarGlobal;
+typedef struct rz_bin_reloc_t RzBinReloc;
 
 class RizinScope : public Scope
 {
@@ -30,6 +31,7 @@ class RizinScope : public Scope
 		uint8 makeId() const { return (*next_id)++; }
 
 		FunctionSymbol *registerFunction(RzAnalysisFunction *fcn) const;
+		FunctionSymbol *registerRelocTarget(RzBinReloc *reloc) const;
 		Symbol *registerFlag(RzFlagItem *flag) const;
 		Symbol *registerGlobalVar(RzAnalysisVarGlobal *glob) const;
 		Symbol *queryRizinAbsolute(ut64 addr, bool contain) const;

test/db/extras/ghidra

@@ -3262,3 +3262,22 @@ undefined8 entry0(int64_t arg1, int64_t arg2)
 }
 EOF
 RUN
+
+NAME=reloc target functions
+FILE=rizin-testbins/elf/linux-example-x86-32.ko
+CMDS=<<EOF
+s sym.ko_example_init
+af
+pdg
+EOF
+EXPECT=<<EOF
+
+undefined4 sym.ko_example_init(void)
+{
+    // [04] -r-x section size 22 named .init.text
+    __fentry__();
+    printk("Hello, Rizin!\n");
+    return 0;
+}
+EOF
+RUN