<nix/buildenv.nix>: Ignore dangling symlinks

Fixes

  error: getting status of '/nix/store/j8p0vv89k1pf0cn7kmfsdcs7bshwga1i-firefox-52.7.2esr/share/icons/hicolor/48x48/apps/firefox.png': No such file or directory

https://github.com/NixOS/nix/issues/1934

Also improve error message on directory/non-directory collisions.
This commit is contained in:
Eelco Dolstra 2018-04-05 20:04:42 +02:00
parent 5c904e10eb
commit 1d9742b95f
No known key found for this signature in database
GPG key ID: 8170B4726D7198DE

View file

@ -9,14 +9,6 @@ namespace nix {
typedef std::map<Path,int> Priorities;
static bool isDirectory(const Path & path)
{
struct stat st;
if (stat(path.c_str(), &st) == -1)
throw SysError(format("getting status of '%1%'") % path);
return S_ISDIR(st.st_mode);
}
// FIXME: change into local variables.
static Priorities priorities;
@ -45,6 +37,18 @@ static void createLinks(const Path & srcDir, const Path & dstDir, int priority)
auto srcFile = srcDir + "/" + ent.name;
auto dstFile = dstDir + "/" + ent.name;
struct stat srcSt;
try {
if (stat(srcFile.c_str(), &srcSt) == -1)
throw SysError("getting status of '%1%'", srcFile);
} catch (SysError & e) {
if (e.errNo == ENOENT || e.errNo == ENOTDIR) {
printError("warning: skipping dangling symlink '%s'", dstFile);
continue;
}
throw;
}
/* The files below are special-cased to that they don't show up
* in user profiles, either because they are useless, or
* because they would cauase pointless collisions (e.g., each
@ -58,7 +62,7 @@ static void createLinks(const Path & srcDir, const Path & dstDir, int priority)
hasSuffix(srcFile, "/log"))
continue;
else if (isDirectory(srcFile)) {
else if (S_ISDIR(srcSt.st_mode)) {
struct stat dstSt;
auto res = lstat(dstFile.c_str(), &dstSt);
if (res == 0) {
@ -66,10 +70,9 @@ static void createLinks(const Path & srcDir, const Path & dstDir, int priority)
createLinks(srcFile, dstFile, priority);
continue;
} else if (S_ISLNK(dstSt.st_mode)) {
auto target = readLink(dstFile);
if (!isDirectory(target))
throw Error(format("collision between '%1%' and non-directory '%2%'")
% srcFile % target);
auto target = canonPath(dstFile, true);
if (!S_ISDIR(lstat(target).st_mode))
throw Error("collision between '%1%' and non-directory '%2%'", srcFile, target);
if (unlink(dstFile.c_str()) == -1)
throw SysError(format("unlinking '%1%'") % dstFile);
if (mkdir(dstFile.c_str(), 0755) == -1)
@ -87,20 +90,20 @@ static void createLinks(const Path & srcDir, const Path & dstDir, int priority)
auto res = lstat(dstFile.c_str(), &dstSt);
if (res == 0) {
if (S_ISLNK(dstSt.st_mode)) {
auto target = readLink(dstFile);
auto prevPriority = priorities[dstFile];
if (prevPriority == priority)
throw Error(format(
throw Error(
"packages '%1%' and '%2%' have the same priority %3%; "
"use 'nix-env --set-flag priority NUMBER INSTALLED_PKGNAME' "
"to change the priority of one of the conflicting packages"
" (0 being the highest priority)"
) % srcFile % target % priority);
" (0 being the highest priority)",
srcFile, readLink(dstFile), priority);
if (prevPriority < priority)
continue;
if (unlink(dstFile.c_str()) == -1)
throw SysError(format("unlinking '%1%'") % dstFile);
}
} else if (S_ISDIR(dstSt.st_mode))
throw Error("collision between non-directory '%1%' and directory '%2%'", srcFile, dstFile);
} else if (errno != ENOENT)
throw SysError(format("getting status of '%1%'") % dstFile);
}