diff options
| -rw-r--r-- | src/nix-env/Makefile.am | 3 | ||||
| -rw-r--r-- | src/nix-env/main.cc | 57 | ||||
| -rw-r--r-- | src/nix-env/profiles.cc | 57 | ||||
| -rw-r--r-- | src/nix-env/profiles.hh | 14 |
4 files changed, 74 insertions, 57 deletions
diff --git a/src/nix-env/Makefile.am b/src/nix-env/Makefile.am index bb418ae06..e4b03943c 100644 --- a/src/nix-env/Makefile.am +++ b/src/nix-env/Makefile.am @@ -1,6 +1,7 @@ bin_PROGRAMS = nix-env -nix_env_SOURCES = main.cc names.cc names.hh help.txt +nix_env_SOURCES = main.cc names.cc names.hh \ + profiles.cc profiles.hh help.txt nix_env_LDADD = ../libmain/libmain.a ../libexpr/libexpr.a \ ../libstore/libstore.a ../libutil/libutil.a \ ../boost/format/libformat.a -L../../externals/inst/lib -ldb_cxx \ diff --git a/src/nix-env/main.cc b/src/nix-env/main.cc index 051236681..87190b620 100644 --- a/src/nix-env/main.cc +++ b/src/nix-env/main.cc @@ -1,5 +1,6 @@ #include <cerrno> +#include "profiles.hh" #include "names.hh" #include "globals.hh" #include "normalise.hh" @@ -138,62 +139,6 @@ void queryInstalled(EvalState & state, DrvInfos & drvs, } -Path createGeneration(Path profile, Path outPath, Path drvPath) -{ - Path profileDir = dirOf(profile); - string profileName = baseNameOf(profile); - - unsigned int num = 0; - - Strings names = readDirectory(profileDir); - for (Strings::iterator i = names.begin(); i != names.end(); ++i) { - if (string(*i, 0, profileName.size() + 1) != profileName + "-") continue; - string s = string(*i, profileName.size() + 1); - int p = s.find("-link"); - if (p == string::npos) continue; - istringstream str(string(s, 0, p)); - unsigned int n; - if (str >> n && str.eof() && n >= num) num = n + 1; - } - - Path generation, gcrootSrc; - - while (1) { - Path prefix = (format("%1%-%2%") % profile % num).str(); - generation = prefix + "-link"; - gcrootSrc = prefix + "-src.gcroot"; - if (symlink(outPath.c_str(), generation.c_str()) == 0) break; - if (errno != EEXIST) - throw SysError(format("creating symlink `%1%'") % generation); - /* Somebody beat us to it, retry with a higher number. */ - num++; - } - - writeStringToFile(gcrootSrc, drvPath); - - return generation; -} - - -void switchLink(Path link, Path target) -{ - /* Hacky. */ - if (dirOf(target) == dirOf(link)) target = baseNameOf(target); - - Path tmp = canonPath(dirOf(link) + "/.new_" + baseNameOf(link)); - if (symlink(target.c_str(), tmp.c_str()) != 0) - throw SysError(format("creating symlink `%1%'") % tmp); - /* The rename() system call is supposed to be essentially atomic - on Unix. That is, if we have links `current -> X' and - `new_current -> Y', and we rename new_current to current, a - process accessing current will see X or Y, but never a - file-not-found or other error condition. This is sufficient to - atomically switch user environments. */ - if (rename(tmp.c_str(), link.c_str()) != 0) - throw SysError(format("renaming `%1%' to `%2%'") % tmp % link); -} - - void createUserEnv(EvalState & state, const DrvInfos & drvs, const Path & profile) { diff --git a/src/nix-env/profiles.cc b/src/nix-env/profiles.cc new file mode 100644 index 000000000..5b9c00406 --- /dev/null +++ b/src/nix-env/profiles.cc @@ -0,0 +1,57 @@ +#include "profiles.hh" + + +Path createGeneration(Path profile, Path outPath, Path drvPath) +{ + Path profileDir = dirOf(profile); + string profileName = baseNameOf(profile); + + unsigned int num = 0; + + Strings names = readDirectory(profileDir); + for (Strings::iterator i = names.begin(); i != names.end(); ++i) { + if (string(*i, 0, profileName.size() + 1) != profileName + "-") continue; + string s = string(*i, profileName.size() + 1); + int p = s.find("-link"); + if (p == string::npos) continue; + istringstream str(string(s, 0, p)); + unsigned int n; + if (str >> n && str.eof() && n >= num) num = n + 1; + } + + Path generation, gcrootSrc; + + while (1) { + Path prefix = (format("%1%-%2%") % profile % num).str(); + generation = prefix + "-link"; + gcrootSrc = prefix + "-src.gcroot"; + if (symlink(outPath.c_str(), generation.c_str()) == 0) break; + if (errno != EEXIST) + throw SysError(format("creating symlink `%1%'") % generation); + /* Somebody beat us to it, retry with a higher number. */ + num++; + } + + writeStringToFile(gcrootSrc, drvPath); + + return generation; +} + + +void switchLink(Path link, Path target) +{ + /* Hacky. */ + if (dirOf(target) == dirOf(link)) target = baseNameOf(target); + + Path tmp = canonPath(dirOf(link) + "/.new_" + baseNameOf(link)); + if (symlink(target.c_str(), tmp.c_str()) != 0) + throw SysError(format("creating symlink `%1%'") % tmp); + /* The rename() system call is supposed to be essentially atomic + on Unix. That is, if we have links `current -> X' and + `new_current -> Y', and we rename new_current to current, a + process accessing current will see X or Y, but never a + file-not-found or other error condition. This is sufficient to + atomically switch user environments. */ + if (rename(tmp.c_str(), link.c_str()) != 0) + throw SysError(format("renaming `%1%' to `%2%'") % tmp % link); +} diff --git a/src/nix-env/profiles.hh b/src/nix-env/profiles.hh new file mode 100644 index 000000000..3d3c86e50 --- /dev/null +++ b/src/nix-env/profiles.hh @@ -0,0 +1,14 @@ +#ifndef __PROFILES_H +#define __PROFILES_H + +#include <string> + +#include "util.hh" + + +Path createGeneration(Path profile, Path outPath, Path drvPath); + +void switchLink(Path link, Path target); + + +#endif /* !__PROFILES_H */ |