tiny.tldr.formats.elf.relocation.kind

1const std = @import("std");2const elf = @import("../root.zig");34const ObjectFile = elf.parser.ObjectFile;5const Symbol = elf.format.Symbol;6const Rela = elf.format.Rela;78pub fn isNone(relocation: Rela) bool {9    return relocation.relocationType() == @backingInt(std.elf.R_X86_64.NONE);10}1112pub fn applicationSupported(relocation_type: u32) bool {13    return switch (relocation_type) {14        @backingInt(std.elf.R_X86_64.NONE),15        @backingInt(std.elf.R_X86_64.@"64"),16        @backingInt(std.elf.R_X86_64.@"32"),17        @backingInt(std.elf.R_X86_64.@"32S"),18        @backingInt(std.elf.R_X86_64.@"16"),19        @backingInt(std.elf.R_X86_64.@"8"),20        @backingInt(std.elf.R_X86_64.PC64),21        @backingInt(std.elf.R_X86_64.PC32),22        @backingInt(std.elf.R_X86_64.PLT32),23        @backingInt(std.elf.R_X86_64.PC16),24        @backingInt(std.elf.R_X86_64.PC8),25        @backingInt(std.elf.R_X86_64.GOTPCREL),26        @backingInt(std.elf.R_X86_64.GOTPCRELX),27        @backingInt(std.elf.R_X86_64.REX_GOTPCRELX),28        @backingInt(std.elf.R_X86_64.SIZE32),29        @backingInt(std.elf.R_X86_64.SIZE64),30        @backingInt(std.elf.R_X86_64.TPOFF32),31        @backingInt(std.elf.R_X86_64.TPOFF64),32        @backingInt(std.elf.R_X86_64.DTPOFF32),33        @backingInt(std.elf.R_X86_64.DTPOFF64),34        @backingInt(std.elf.R_X86_64.GOTTPOFF),35        @backingInt(std.elf.R_X86_64.TLSGD),36        @backingInt(std.elf.R_X86_64.TLSLD),37        => true,38        else => false,39    };40}4142test "application support pins the apply switch arms" {43    try std.testing.expect(applicationSupported(@backingInt(std.elf.R_X86_64.NONE)));44    try std.testing.expect(applicationSupported(@backingInt(std.elf.R_X86_64.PC32)));45    try std.testing.expect(applicationSupported(@backingInt(std.elf.R_X86_64.REX_GOTPCRELX)));46    try std.testing.expect(applicationSupported(@backingInt(std.elf.R_X86_64.TLSLD)));47    try std.testing.expect(!applicationSupported(@backingInt(std.elf.R_X86_64.GOT32)));48    try std.testing.expect(!applicationSupported(@backingInt(std.elf.R_X86_64.COPY)));49    try std.testing.expect(!applicationSupported(@backingInt(std.elf.R_X86_64.JUMP_SLOT)));50    try std.testing.expect(!applicationSupported(@backingInt(std.elf.R_X86_64.TLSDESC)));51}5253pub fn isRelaxedTlsRuntimeResolver(object: ObjectFile, relocations: []const Rela, relocation_index: usize) bool {54    const relocation = relocations[relocation_index];55    if (!isTlsRuntimeResolverRelocationType(relocation.relocationType())) return false;56    if (relocation.symbolIndex() >= object.symbols.len) return false;57    if (!isTlsRuntimeResolverSymbol(object.symbols[@intCast(relocation.symbolIndex())])) return false;5859    var index = relocation_index;60    while (index > 0) {61        index -= 1;62        const marker = relocations[index];63        if (isNone(marker)) continue;64        if (!isTlsDynamicModelRelocationType(marker.relocationType())) return false;65        if (relocation.offset <= marker.offset) return false;66        return relocation.offset - marker.offset <= 12;67    }68    return false;69}7071fn isTlsRuntimeResolverRelocationType(relocation_type: u32) bool {72    return switch (relocation_type) {73        @backingInt(std.elf.R_X86_64.PLT32),74        @backingInt(std.elf.R_X86_64.GOTPCREL),75        @backingInt(std.elf.R_X86_64.GOTPCRELX),76        @backingInt(std.elf.R_X86_64.REX_GOTPCRELX),77        => true,78        else => false,79    };80}8182fn isTlsDynamicModelRelocationType(relocation_type: u32) bool {83    return switch (relocation_type) {84        @backingInt(std.elf.R_X86_64.TLSGD),85        @backingInt(std.elf.R_X86_64.TLSLD),86        => true,87        else => false,88    };89}9091fn isTlsRuntimeResolverSymbol(symbol: Symbol) bool {92    return std.mem.eql(u8, symbol.name, "__tls_get_addr");93}

1pub const kind = @import("kind.zig");