Merge "Add symbols for start and end of embedded linker" (0bcba808) · Commits · e / os / android_build_soong

cmd/extract_linker/main.go

+36 −16

Original line number	Diff line number	Diff line
		@@ -26,7 +26,7 @@ import (
		"io/ioutil"
		"log"
		"os"
		"strings"
		"strconv"
		)

		func main() {
		@@ -59,20 +59,16 @@ func main() {
		fmt.Fprintln(script, "ENTRY(__dlwrap__start)")
		fmt.Fprintln(script, "SECTIONS {")

		progsWithFlagsCount := make(map[string]int)

		for _, prog := range ef.Progs {
		if prog.Type != elf.PT_LOAD {
		continue
		}

		var progName string
		progSection := progToFirstSection(prog, ef.Sections)
		if progSection != nil {
		progName = progSection.Name
		} else {
		progName = fmt.Sprintf(".sect%d", load)
		}
		sectionName := ".linker" + progName
		symName := "__dlwrap_linker" + strings.ReplaceAll(progName, ".", "_")
		progName := progNameFromFlags(prog.Flags, progsWithFlagsCount)
		sectionName := ".linker_" + progName
		symName := "__dlwrap_linker_" + progName

		flags := ""
		if prog.Flags&elf.PF_W != 0 {
		@@ -83,6 +79,12 @@ func main() {
		}
		fmt.Fprintf(asm, ".section %s, \"a%s\"\n", sectionName, flags)

		if load == 0 {
		fmt.Fprintln(asm, ".globl __dlwrap_linker")
		fmt.Fprintln(asm, "__dlwrap_linker:")
		fmt.Fprintln(asm)
		}

		fmt.Fprintf(asm, ".globl %s\n%s:\n\n", symName, symName)

		fmt.Fprintf(script, " %s 0x%x : {\n", sectionName, baseLoadAddr+prog.Vaddr)
		@@ -106,6 +108,10 @@ func main() {
		load += 1
		}

		fmt.Fprintln(asm, ".globl __dlwrap_linker_end")
		fmt.Fprintln(asm, "__dlwrap_linker_end:")
		fmt.Fprintln(asm)

		fmt.Fprintln(asm, `.section .note.android.embedded_linker,"a",%note`)

		fmt.Fprintln(script, "}")
		@@ -139,11 +145,25 @@ func bytesToAsm(asm io.Writer, buf []byte) {
		fmt.Fprintln(asm)
		}

		func progToFirstSection(prog elf.Prog, sections []elf.Section) *elf.Section {
		for _, section := range sections {
		if section.Addr == prog.Vaddr {
		return section
		func progNameFromFlags(flags elf.ProgFlag, progsWithFlagsCount map[string]int) string {
		s := ""
		if flags&elf.PF_R != 0 {
		s += "r"
		}
		if flags&elf.PF_W != 0 {
		s += "w"
		}
		if flags&elf.PF_X != 0 {
		s += "x"
		}

		count := progsWithFlagsCount[s]
		count++
		progsWithFlagsCount[s] = count

		if count > 1 {
		s += strconv.Itoa(count)
		}
		return nil

		return s
		}