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-rw-r--r--tools/llvm-objcopy/ELF/ELFConfig.cpp133
1 files changed, 133 insertions, 0 deletions
diff --git a/tools/llvm-objcopy/ELF/ELFConfig.cpp b/tools/llvm-objcopy/ELF/ELFConfig.cpp
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index 000000000000..40993760add7
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+++ b/tools/llvm-objcopy/ELF/ELFConfig.cpp
@@ -0,0 +1,133 @@
+//===- ELFConfig.cpp ------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "CopyConfig.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/Error.h"
+
+namespace llvm {
+namespace objcopy {
+namespace elf {
+
+static Expected<NewSymbolInfo> parseNewSymbolInfo(StringRef FlagValue,
+ uint8_t DefaultVisibility) {
+ // Parse value given with --add-symbol option and create the
+ // new symbol if possible. The value format for --add-symbol is:
+ //
+ // <name>=[<section>:]<value>[,<flags>]
+ //
+ // where:
+ // <name> - symbol name, can be empty string
+ // <section> - optional section name. If not given ABS symbol is created
+ // <value> - symbol value, can be decimal or hexadecimal number prefixed
+ // with 0x.
+ // <flags> - optional flags affecting symbol type, binding or visibility:
+ // The following are currently supported:
+ //
+ // global, local, weak, default, hidden, file, section, object,
+ // indirect-function.
+ //
+ // The following flags are ignored and provided for GNU
+ // compatibility only:
+ //
+ // warning, debug, constructor, indirect, synthetic,
+ // unique-object, before=<symbol>.
+ NewSymbolInfo SI;
+ StringRef Value;
+ std::tie(SI.SymbolName, Value) = FlagValue.split('=');
+ if (Value.empty())
+ return createStringError(
+ errc::invalid_argument,
+ "bad format for --add-symbol, missing '=' after '%s'",
+ SI.SymbolName.str().c_str());
+
+ if (Value.contains(':')) {
+ std::tie(SI.SectionName, Value) = Value.split(':');
+ if (SI.SectionName.empty() || Value.empty())
+ return createStringError(
+ errc::invalid_argument,
+ "bad format for --add-symbol, missing section name or symbol value");
+ }
+
+ SmallVector<StringRef, 6> Flags;
+ Value.split(Flags, ',');
+ if (Flags[0].getAsInteger(0, SI.Value))
+ return createStringError(errc::invalid_argument, "bad symbol value: '%s'",
+ Flags[0].str().c_str());
+
+ SI.Visibility = DefaultVisibility;
+
+ using Functor = std::function<void(void)>;
+ SmallVector<StringRef, 6> UnsupportedFlags;
+ for (size_t I = 1, NumFlags = Flags.size(); I < NumFlags; ++I)
+ static_cast<Functor>(
+ StringSwitch<Functor>(Flags[I])
+ .CaseLower("global", [&SI] { SI.Bind = ELF::STB_GLOBAL; })
+ .CaseLower("local", [&SI] { SI.Bind = ELF::STB_LOCAL; })
+ .CaseLower("weak", [&SI] { SI.Bind = ELF::STB_WEAK; })
+ .CaseLower("default", [&SI] { SI.Visibility = ELF::STV_DEFAULT; })
+ .CaseLower("hidden", [&SI] { SI.Visibility = ELF::STV_HIDDEN; })
+ .CaseLower("protected",
+ [&SI] { SI.Visibility = ELF::STV_PROTECTED; })
+ .CaseLower("file", [&SI] { SI.Type = ELF::STT_FILE; })
+ .CaseLower("section", [&SI] { SI.Type = ELF::STT_SECTION; })
+ .CaseLower("object", [&SI] { SI.Type = ELF::STT_OBJECT; })
+ .CaseLower("function", [&SI] { SI.Type = ELF::STT_FUNC; })
+ .CaseLower("indirect-function",
+ [&SI] { SI.Type = ELF::STT_GNU_IFUNC; })
+ .CaseLower("debug", [] {})
+ .CaseLower("constructor", [] {})
+ .CaseLower("warning", [] {})
+ .CaseLower("indirect", [] {})
+ .CaseLower("synthetic", [] {})
+ .CaseLower("unique-object", [] {})
+ .StartsWithLower("before", [] {})
+ .Default([&] { UnsupportedFlags.push_back(Flags[I]); }))();
+ if (!UnsupportedFlags.empty())
+ return createStringError(errc::invalid_argument,
+ "unsupported flag%s for --add-symbol: '%s'",
+ UnsupportedFlags.size() > 1 ? "s" : "",
+ join(UnsupportedFlags, "', '").c_str());
+ return SI;
+}
+
+Expected<ELFCopyConfig> parseConfig(const CopyConfig &Config) {
+ ELFCopyConfig ELFConfig;
+ if (Config.NewSymbolVisibility) {
+ const uint8_t Invalid = 0xff;
+ ELFConfig.NewSymbolVisibility =
+ StringSwitch<uint8_t>(*Config.NewSymbolVisibility)
+ .Case("default", ELF::STV_DEFAULT)
+ .Case("hidden", ELF::STV_HIDDEN)
+ .Case("internal", ELF::STV_INTERNAL)
+ .Case("protected", ELF::STV_PROTECTED)
+ .Default(Invalid);
+
+ if (ELFConfig.NewSymbolVisibility == Invalid)
+ return createStringError(errc::invalid_argument,
+ "'%s' is not a valid symbol visibility",
+ Config.NewSymbolVisibility->str().c_str());
+ }
+
+ for (StringRef Arg : Config.SymbolsToAdd) {
+ Expected<elf::NewSymbolInfo> NSI = parseNewSymbolInfo(
+ Arg,
+ ELFConfig.NewSymbolVisibility.getValueOr((uint8_t)ELF::STV_DEFAULT));
+ if (!NSI)
+ return NSI.takeError();
+ ELFConfig.SymbolsToAdd.push_back(*NSI);
+ }
+
+ return ELFConfig;
+}
+
+} // end namespace elf
+} // end namespace objcopy
+} // end namespace llvm