lix-project/lix-releng-staging
0
0
Fork 0
Code Packages Activity

Generations API cleanup

Browse source
This commit is contained in:
Eelco Dolstra 2020-07-16 15:14:22 +02:00
parent 8807ff902e
commit 5517eee17e
3 changed files with 59 additions and 75 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

81
src/libstore/profiles.cc
View file

@ -12,30 +12,24 @@
namespace nix {
static bool cmpGensByNumber(const Generation & a, const Generation & b)
{
return a.number < b.number;
}
/* Parse a generation name of the format
`<profilename>-<number>-link'. */
static int parseName(const string & profileName, const string & name)
static std::optional<GenerationNumber> parseName(const string & profileName, const string & name)
{
if (string(name, 0, profileName.size() + 1) != profileName + "-") return -1;
if (string(name, 0, profileName.size() + 1) != profileName + "-") return {};
string s = string(name, profileName.size() + 1);
string::size_type p = s.find("-link");
if (p == string::npos) return -1;
int n;
if (p == string::npos) return {};
unsigned int n;
if (string2Int(string(s, 0, p), n) && n >= 0)
return n;
else
return -1;
return {};
}
Generations findGenerations(Path profile, int & curGen)
std::pair<Generations, std::optional<GenerationNumber>> findGenerations(Path profile)
{
Generations gens;
@ -43,30 +37,34 @@ Generations findGenerations(Path profile, int & curGen)
auto profileName = std::string(baseNameOf(profile));
for (auto & i : readDirectory(profileDir)) {
int n;
if ((n = parseName(profileName, i.name)) != -1) {
Generation gen;
gen.path = profileDir + "/" + i.name;
gen.number = n;
if (auto n = parseName(profileName, i.name)) {
auto path = profileDir + "/" + i.name;
struct stat st;
if (lstat(gen.path.c_str(), &st) != 0)
throw SysError("statting '%1%'", gen.path);
gen.creationTime = st.st_mtime;
gens.push_back(gen);
if (lstat(path.c_str(), &st) != 0)
throw SysError("statting '%1%'", path);
gens.push_back({
.number = *n,
.path = path,
.creationTime = st.st_mtime
});
}
}
gens.sort(cmpGensByNumber);
gens.sort([](const Generation & a, const Generation & b)
{
return a.number < b.number;
});
curGen = pathExists(profile)
return {
gens,
pathExists(profile)
? parseName(profileName, readLink(profile))
: -1;
return gens;
: std::nullopt
};
}
static void makeName(const Path & profile, unsigned int num,
static void makeName(const Path & profile, GenerationNumber num,
Path & outLink)
{
Path prefix = (format("%1%-%2%") % profile % num).str();
@ -78,10 +76,9 @@ Path createGeneration(ref<LocalFSStore> store, Path profile, Path outPath)
{
/* The new generation number should be higher than old the
previous ones. */
int dummy;
Generations gens = findGenerations(profile, dummy);
auto [gens, dummy] = findGenerations(profile);
unsigned int num;
GenerationNumber num;
if (gens.size() > 0) {
Generation last = gens.back();
@ -121,7 +118,7 @@ static void removeFile(const Path & path)
}
void deleteGeneration(const Path & profile, unsigned int gen)
void deleteGeneration(const Path & profile, GenerationNumber gen)
{
Path generation;
makeName(profile, gen, generation);
@ -129,7 +126,7 @@ void deleteGeneration(const Path & profile, unsigned int gen)
}
static void deleteGeneration2(const Path & profile, unsigned int gen, bool dryRun)
static void deleteGeneration2(const Path & profile, GenerationNumber gen, bool dryRun)
{
if (dryRun)
printInfo(format("would remove generation %1%") % gen);
@ -140,31 +137,29 @@ static void deleteGeneration2(const Path & profile, unsigned int gen, bool dryRu
}
void deleteGenerations(const Path & profile, const std::set<unsigned int> & gensToDelete, bool dryRun)
void deleteGenerations(const Path & profile, const std::set<GenerationNumber> & gensToDelete, bool dryRun)
{
PathLocks lock;
lockProfile(lock, profile);
int curGen;
Generations gens = findGenerations(profile, curGen);
auto [gens, curGen] = findGenerations(profile);
if (gensToDelete.find(curGen) != gensToDelete.end())
if (gensToDelete.count(*curGen))
throw Error("cannot delete current generation of profile %1%'", profile);
for (auto & i : gens) {
if (gensToDelete.find(i.number) == gensToDelete.end()) continue;
if (!gensToDelete.count(i.number)) continue;
deleteGeneration2(profile, i.number, dryRun);
}
}
void deleteGenerationsGreaterThan(const Path & profile, int max, bool dryRun)
void deleteGenerationsGreaterThan(const Path & profile, GenerationNumber max, bool dryRun)
{
PathLocks lock;
lockProfile(lock, profile);
int curGen;
bool fromCurGen = false;
Generations gens = findGenerations(profile, curGen);
auto [gens, curGen] = findGenerations(profile);
for (auto i = gens.rbegin(); i != gens.rend(); ++i) {
if (i->number == curGen) {
fromCurGen = true;
@ -186,8 +181,7 @@ void deleteOldGenerations(const Path & profile, bool dryRun)
PathLocks lock;
lockProfile(lock, profile);
int curGen;
Generations gens = findGenerations(profile, curGen);
auto [gens, curGen] = findGenerations(profile);
for (auto & i : gens)
if (i.number != curGen)
@ -200,8 +194,7 @@ void deleteGenerationsOlderThan(const Path & profile, time_t t, bool dryRun)
PathLocks lock;
lockProfile(lock, profile);
int curGen;
Generations gens = findGenerations(profile, curGen);
auto [gens, curGen] = findGenerations(profile);
bool canDelete = false;
for (auto i = gens.rbegin(); i != gens.rend(); ++i)

25
src/libstore/profiles.hh
View file

@ -9,37 +9,32 @@
namespace nix {
typedef unsigned int GenerationNumber;
struct Generation
{
int number;
GenerationNumber number;
Path path;
time_t creationTime;
Generation()
{
number = -1;
}
operator bool() const
{
return number != -1;
}
};
typedef list<Generation> Generations;
typedef std::list<Generation> Generations;
/* Returns the list of currently present generations for the specified
profile, sorted by generation number. */
Generations findGenerations(Path profile, int & curGen);
profile, sorted by generation number. Also returns the number of
the current generation. */
std::pair<Generations, std::optional<GenerationNumber>> findGenerations(Path profile);
class LocalFSStore;
Path createGeneration(ref<LocalFSStore> store, Path profile, Path outPath);
void deleteGeneration(const Path & profile, unsigned int gen);
void deleteGeneration(const Path & profile, GenerationNumber gen);
void deleteGenerations(const Path & profile, const std::set<unsigned int> & gensToDelete, bool dryRun);
void deleteGenerations(const Path & profile, const std::set<GenerationNumber> & gensToDelete, bool dryRun);
void deleteGenerationsGreaterThan(const Path & profile, const int max, bool dryRun);
void deleteGenerationsGreaterThan(const Path & profile, GenerationNumber max, bool dryRun);
void deleteOldGenerations(const Path & profile, bool dryRun);

28
src/nix-env/nix-env.cc
View file

@ -1208,18 +1208,17 @@ static void opSwitchProfile(Globals & globals, Strings opFlags, Strings opArgs)
}
static const int prevGen = -2;
static constexpr GenerationNumber prevGen = std::numeric_limits<GenerationNumber>::max();
static void switchGeneration(Globals & globals, int dstGen)
static void switchGeneration(Globals & globals, GenerationNumber dstGen)
{
PathLocks lock;
lockProfile(lock, globals.profile);
int curGen;
Generations gens = findGenerations(globals.profile, curGen);
auto [gens, curGen] = findGenerations(globals.profile);
Generation dst;
std::optional<Generation> dst;
for (auto & i : gens)
if ((dstGen == prevGen && i.number < curGen) ||
(dstGen >= 0 && i.number == dstGen))
@ -1227,18 +1226,16 @@ static void switchGeneration(Globals & globals, int dstGen)
if (!dst) {
if (dstGen == prevGen)
throw Error("no generation older than the current (%1%) exists",
curGen);
throw Error("no generation older than the current (%1%) exists", curGen.value_or(0));
else
throw Error("generation %1% does not exist", dstGen);
}
printInfo(format("switching from generation %1% to %2%")
% curGen % dst.number);
printInfo("switching from generation %1% to %2%", curGen.value_or(0), dst->number);
if (globals.dryRun) return;
switchLink(globals.profile, dst.path);
switchLink(globals.profile, dst->path);
}
@ -1249,7 +1246,7 @@ static void opSwitchGeneration(Globals & globals, Strings opFlags, Strings opArg
if (opArgs.size() != 1)
throw UsageError("exactly one argument expected");
int dstGen;
GenerationNumber dstGen;
if (!string2Int(opArgs.front(), dstGen))
throw UsageError("expected a generation number");
@ -1278,8 +1275,7 @@ static void opListGenerations(Globals & globals, Strings opFlags, Strings opArgs
PathLocks lock;
lockProfile(lock, globals.profile);
int curGen;
Generations gens = findGenerations(globals.profile, curGen);
auto [gens, curGen] = findGenerations(globals.profile);
RunPager pager;
@ -1308,14 +1304,14 @@ static void opDeleteGenerations(Globals & globals, Strings opFlags, Strings opAr
if(opArgs.front().size() < 2)
throw Error("invalid number of generations ‘%1%’", opArgs.front());
string str_max = string(opArgs.front(), 1, opArgs.front().size());
int max;
GenerationNumber max;
if (!string2Int(str_max, max) || max == 0)
throw Error("invalid number of generations to keep ‘%1%’", opArgs.front());
deleteGenerationsGreaterThan(globals.profile, max, globals.dryRun);
} else {
std::set<unsigned int> gens;
std::set<GenerationNumber> gens;
for (auto & i : opArgs) {
unsigned int n;
GenerationNumber n;
if (!string2Int(i, n))
throw UsageError("invalid generation number '%1%'", i);
gens.insert(n);