diff options
| -rw-r--r-- | src/libstore/profiles.cc | 31 | ||||
| -rw-r--r-- | src/libstore/profiles.hh | 9 | ||||
| -rw-r--r-- | src/libutil/args.hh | 8 | ||||
| -rw-r--r-- | src/nix-env/nix-env.cc | 35 | ||||
| -rw-r--r-- | src/nix/profile-rollback.md | 26 | ||||
| -rw-r--r-- | src/nix/profile.cc | 33 |
6 files changed, 108 insertions, 34 deletions
diff --git a/src/libstore/profiles.cc b/src/libstore/profiles.cc index 84a21c0ba..9959da535 100644 --- a/src/libstore/profiles.cc +++ b/src/libstore/profiles.cc @@ -236,6 +236,37 @@ void switchLink(Path link, Path target) } +void switchGeneration( + const Path & profile, + std::optional<GenerationNumber> dstGen, + bool dryRun) +{ + PathLocks lock; + lockProfile(lock, profile); + + auto [gens, curGen] = findGenerations(profile); + + std::optional<Generation> dst; + for (auto & i : gens) + if ((!dstGen && i.number < curGen) || + (dstGen && i.number == *dstGen)) + dst = i; + + if (!dst) { + if (dstGen) + throw Error("generation %1% does not exist", *dstGen); + else + throw Error("no generation older than the current (%1%) exists", curGen.value_or(0)); + } + + notice("switching from generation %d to %d", curGen.value_or(0), dst->number); + + if (dryRun) return; + + switchLink(profile, dst->path); +} + + void lockProfile(PathLocks & lock, const Path & profile) { lock.lockPaths({profile}, (format("waiting for lock on profile '%1%'") % profile).str()); diff --git a/src/libstore/profiles.hh b/src/libstore/profiles.hh index be55a65d4..d100c970c 100644 --- a/src/libstore/profiles.hh +++ b/src/libstore/profiles.hh @@ -11,7 +11,7 @@ namespace nix { class StorePath; -typedef unsigned int GenerationNumber; +typedef uint64_t GenerationNumber; struct Generation { @@ -46,6 +46,13 @@ void deleteGenerationsOlderThan(const Path & profile, const string & timeSpec, b void switchLink(Path link, Path target); +/* Roll back a profile to the specified generation, or to the most + recent one older than the current. */ +void switchGeneration( + const Path & profile, + std::optional<GenerationNumber> dstGen, + bool dryRun); + /* Ensure exclusive access to a profile. Any command that modifies the profile first acquires this lock. */ void lockProfile(PathLocks & lock, const Path & profile); diff --git a/src/libutil/args.hh b/src/libutil/args.hh index 22c94b501..7521b3065 100644 --- a/src/libutil/args.hh +++ b/src/libutil/args.hh @@ -91,6 +91,14 @@ protected: }) , arity(1) { } + + template<class I> + Handler(std::optional<I> * dest) + : fun([=](std::vector<std::string> ss) { + *dest = string2IntWithUnitPrefix<I>(ss[0]); + }) + , arity(1) + { } }; /* Options. */ diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc index e04954d45..20bbc2064 100644 --- a/src/nix-env/nix-env.cc +++ b/src/nix-env/nix-env.cc @@ -1204,37 +1204,6 @@ static void opSwitchProfile(Globals & globals, Strings opFlags, Strings opArgs) } -static constexpr GenerationNumber prevGen = std::numeric_limits<GenerationNumber>::max(); - - -static void switchGeneration(Globals & globals, GenerationNumber dstGen) -{ - PathLocks lock; - lockProfile(lock, globals.profile); - - auto [gens, curGen] = findGenerations(globals.profile); - - std::optional<Generation> dst; - for (auto & i : gens) - if ((dstGen == prevGen && i.number < curGen) || - (dstGen >= 0 && i.number == dstGen)) - dst = i; - - if (!dst) { - if (dstGen == prevGen) - throw Error("no generation older than the current (%1%) exists", curGen.value_or(0)); - else - throw Error("generation %1% does not exist", dstGen); - } - - printInfo("switching from generation %1% to %2%", curGen.value_or(0), dst->number); - - if (globals.dryRun) return; - - switchLink(globals.profile, dst->path); -} - - static void opSwitchGeneration(Globals & globals, Strings opFlags, Strings opArgs) { if (opFlags.size() > 0) @@ -1243,7 +1212,7 @@ static void opSwitchGeneration(Globals & globals, Strings opFlags, Strings opArg throw UsageError("exactly one argument expected"); if (auto dstGen = string2Int<GenerationNumber>(opArgs.front())) - switchGeneration(globals, *dstGen); + switchGeneration(globals.profile, *dstGen, globals.dryRun); else throw UsageError("expected a generation number"); } @@ -1256,7 +1225,7 @@ static void opRollback(Globals & globals, Strings opFlags, Strings opArgs) if (opArgs.size() != 0) throw UsageError("no arguments expected"); - switchGeneration(globals, prevGen); + switchGeneration(globals.profile, {}, globals.dryRun); } diff --git a/src/nix/profile-rollback.md b/src/nix/profile-rollback.md new file mode 100644 index 000000000..fccdbb10e --- /dev/null +++ b/src/nix/profile-rollback.md @@ -0,0 +1,26 @@ +R""( + +# Examples + +* Roll back your default profile to the previous version: + + ```console + # nix profile rollback + switching from generation 519 to 518 + ``` + +* Switch your default profile to version 510: + + ```console + # nix profile rollback --to 510 + switching from generation 518 to 510 + ``` + +# Description + +This command switches a profile to the most recent version older +than the currently active version, or if `--to` *N* is given, to +version *N* of the profile. To see the available versions of a +profile, use `nix profile history`. + +)"" diff --git a/src/nix/profile.cc b/src/nix/profile.cc index 8cef6d0b6..4c4a9bff4 100644 --- a/src/nix/profile.cc +++ b/src/nix/profile.cc @@ -543,6 +543,38 @@ struct CmdProfileHistory : virtual StoreCommand, EvalCommand, MixDefaultProfile } }; +struct CmdProfileRollback : virtual StoreCommand, MixDefaultProfile, MixDryRun +{ + std::optional<GenerationNumber> version; + + CmdProfileRollback() + { + addFlag({ + .longName = "to", + .description = "The profile version to roll back to.", + .labels = {"version"}, + .handler = {&version}, + }); + } + + std::string description() override + { + return "roll back to the previous version or a specified version of this profile"; + } + + std::string doc() override + { + return + #include "profile-rollback.md" + ; + } + + void run(ref<Store> store) override + { + switchGeneration(*profile, version, dryRun); + } +}; + struct CmdProfile : NixMultiCommand { CmdProfile() @@ -553,6 +585,7 @@ struct CmdProfile : NixMultiCommand {"list", []() { return make_ref<CmdProfileList>(); }}, {"diff-closures", []() { return make_ref<CmdProfileDiffClosures>(); }}, {"history", []() { return make_ref<CmdProfileHistory>(); }}, + {"rollback", []() { return make_ref<CmdProfileRollback>(); }}, }) { } |