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-rw-r--r--nix/libutil/archive.cc171
-rw-r--r--nix/libutil/archive.hh12
-rw-r--r--nix/libutil/serialise.cc27
-rw-r--r--nix/libutil/serialise.hh11
-rw-r--r--nix/libutil/types.hh17
-rw-r--r--nix/libutil/util.cc176
-rw-r--r--nix/libutil/util.hh30
7 files changed, 272 insertions, 172 deletions
diff --git a/nix/libutil/archive.cc b/nix/libutil/archive.cc
index 70a1c580dd..6856ea0f28 100644
--- a/nix/libutil/archive.cc
+++ b/nix/libutil/archive.cc
@@ -1,10 +1,14 @@
+#define _XOPEN_SOURCE 600
+
 #include "config.h"
 
 #include <cerrno>
 #include <algorithm>
 #include <vector>
+#include <map>
+
+#include <strings.h> // for strcasecmp
 
-#define _XOPEN_SOURCE 600
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
@@ -18,39 +22,21 @@
 namespace nix {
 
 
+bool useCaseHack =
+#if __APPLE__
+    true;
+#else
+    false;
+#endif
+
 static string archiveVersion1 = "nix-archive-1";
 
+static string caseHackSuffix = "~nix~case~hack~";
 
 PathFilter defaultPathFilter;
 
 
-static void dump(const string & path, Sink & sink, PathFilter & filter);
-
-
-static void dumpEntries(const Path & path, Sink & sink, PathFilter & filter)
-{
-    Strings names = readDirectory(path);
-    vector<string> names2(names.begin(), names.end());
-    sort(names2.begin(), names2.end());
-
-    for (vector<string>::iterator i = names2.begin();
-         i != names2.end(); ++i)
-    {
-        Path entry = path + "/" + *i;
-        if (filter(entry)) {
-            writeString("entry", sink);
-            writeString("(", sink);
-            writeString("name", sink);
-            writeString(*i, sink);
-            writeString("node", sink);
-            dump(entry, sink, filter);
-            writeString(")", sink);
-        }
-    }
-}
-
-
-static void dumpContents(const Path & path, size_t size, 
+static void dumpContents(const Path & path, size_t size,
     Sink & sink)
 {
     writeString("contents", sink);
@@ -58,7 +44,7 @@ static void dumpContents(const Path & path, size_t size,
 
     AutoCloseFD fd = open(path.c_str(), O_RDONLY);
     if (fd == -1) throw SysError(format("opening file `%1%'") % path);
-    
+
     unsigned char buf[65536];
     size_t left = size;
 
@@ -89,12 +75,40 @@ static void dump(const Path & path, Sink & sink, PathFilter & filter)
             writeString("", sink);
         }
         dumpContents(path, (size_t) st.st_size, sink);
-    } 
+    }
 
     else if (S_ISDIR(st.st_mode)) {
         writeString("type", sink);
         writeString("directory", sink);
-        dumpEntries(path, sink, filter);
+
+        /* If we're on a case-insensitive system like Mac OS X, undo
+           the case hack applied by restorePath(). */
+        std::map<string, string> unhacked;
+        for (auto & i : readDirectory(path))
+            if (useCaseHack) {
+                string name(i.name);
+                size_t pos = i.name.find(caseHackSuffix);
+                if (pos != string::npos) {
+                    printMsg(lvlDebug, format("removing case hack suffix from `%1%'") % (path + "/" + i.name));
+                    name.erase(pos);
+                }
+                if (unhacked.find(name) != unhacked.end())
+                    throw Error(format("file name collision in between `%1%' and `%2%'")
+                        % (path + "/" + unhacked[name]) % (path + "/" + i.name));
+                unhacked[name] = i.name;
+            } else
+                unhacked[i.name] = i.name;
+
+        for (auto & i : unhacked)
+            if (filter(path + "/" + i.first)) {
+                writeString("entry", sink);
+                writeString("(", sink);
+                writeString("name", sink);
+                writeString(i.first, sink);
+                writeString("node", sink);
+                dump(path + "/" + i.second, sink, filter);
+                writeString(")", sink);
+            }
     }
 
     else if (S_ISLNK(st.st_mode)) {
@@ -123,6 +137,7 @@ static SerialisationError badArchive(string s)
 }
 
 
+#if 0
 static void skipGeneric(Source & source)
 {
     if (readString(source) == "(") {
@@ -130,43 +145,13 @@ static void skipGeneric(Source & source)
             skipGeneric(source);
     }
 }
-
-
-static void parse(ParseSink & sink, Source & source, const Path & path);
-
-
-
-static void parseEntry(ParseSink & sink, Source & source, const Path & path)
-{
-    string s, name;
-
-    s = readString(source);
-    if (s != "(") throw badArchive("expected open tag");
-
-    while (1) {
-        checkInterrupt();
-
-        s = readString(source);
-
-        if (s == ")") {
-            break;
-        } else if (s == "name") {
-            name = readString(source);
-        } else if (s == "node") {
-            if (s == "") throw badArchive("entry name missing");
-            parse(sink, source, path + "/" + name);
-        } else {
-            throw badArchive("unknown field " + s);
-            skipGeneric(source);
-        }
-    }
-}
+#endif
 
 
 static void parseContents(ParseSink & sink, Source & source, const Path & path)
 {
     unsigned long long size = readLongLong(source);
-    
+
     sink.preallocateContents(size);
 
     unsigned long long left = size;
@@ -185,6 +170,15 @@ static void parseContents(ParseSink & sink, Source & source, const Path & path)
 }
 
 
+struct CaseInsensitiveCompare
+{
+    bool operator() (const string & a, const string & b) const
+    {
+        return strcasecmp(a.c_str(), b.c_str()) < 0;
+    }
+};
+
+
 static void parse(ParseSink & sink, Source & source, const Path & path)
 {
     string s;
@@ -194,6 +188,8 @@ static void parse(ParseSink & sink, Source & source, const Path & path)
 
     enum { tpUnknown, tpRegular, tpDirectory, tpSymlink } type = tpUnknown;
 
+    std::map<Path, int, CaseInsensitiveCompare> names;
+
     while (1) {
         checkInterrupt();
 
@@ -221,9 +217,9 @@ static void parse(ParseSink & sink, Source & source, const Path & path)
             else if (t == "symlink") {
                 type = tpSymlink;
             }
-            
+
             else throw badArchive("unknown file type " + t);
-            
+
         }
 
         else if (s == "contents" && type == tpRegular) {
@@ -236,7 +232,40 @@ static void parse(ParseSink & sink, Source & source, const Path & path)
         }
 
         else if (s == "entry" && type == tpDirectory) {
-            parseEntry(sink, source, path);
+            string name, prevName;
+
+            s = readString(source);
+            if (s != "(") throw badArchive("expected open tag");
+
+            while (1) {
+                checkInterrupt();
+
+                s = readString(source);
+
+                if (s == ")") {
+                    break;
+                } else if (s == "name") {
+                    name = readString(source);
+                    if (name.empty() || name == "." || name == ".." || name.find('/') != string::npos || name.find((char) 0) != string::npos)
+                        throw Error(format("NAR contains invalid file name `%1%'") % name);
+                    if (name <= prevName)
+                        throw Error("NAR directory is not sorted");
+                    prevName = name;
+                    if (useCaseHack) {
+                        auto i = names.find(name);
+                        if (i != names.end()) {
+                            printMsg(lvlDebug, format("case collision between `%1%' and `%2%'") % i->first % name);
+                            name += caseHackSuffix;
+                            name += int2String(++i->second);
+                        } else
+                            names[name] = 0;
+                    }
+                } else if (s == "node") {
+                    if (s.empty()) throw badArchive("entry name missing");
+                    parse(sink, source, path + "/" + name);
+                } else
+                    throw badArchive("unknown field " + s);
+            }
         }
 
         else if (s == "target" && type == tpSymlink) {
@@ -244,17 +273,15 @@ static void parse(ParseSink & sink, Source & source, const Path & path)
             sink.createSymlink(path, target);
         }
 
-        else {
+        else
             throw badArchive("unknown field " + s);
-            skipGeneric(source);
-        }
     }
 }
 
 
 void parseDump(ParseSink & sink, Source & source)
 {
-    string version;    
+    string version;
     try {
         version = readString(source);
     } catch (SerialisationError & e) {
@@ -323,7 +350,7 @@ struct RestoreSink : ParseSink
     }
 };
 
- 
+
 void restorePath(const Path & path, Source & source)
 {
     RestoreSink sink;
@@ -331,5 +358,5 @@ void restorePath(const Path & path, Source & source)
     parseDump(sink, source);
 }
 
- 
+
 }
diff --git a/nix/libutil/archive.hh b/nix/libutil/archive.hh
index ccac92074d..c216e9768f 100644
--- a/nix/libutil/archive.hh
+++ b/nix/libutil/archive.hh
@@ -28,7 +28,7 @@ namespace nix {
 
    where:
 
-     attrs(as) = concat(map(attr, as)) + encN(0) 
+     attrs(as) = concat(map(attr, as)) + encN(0)
      attrs((a, b)) = encS(a) + encS(b)
 
      encS(s) = encN(len(s)) + s + (padding until next 64-bit boundary)
@@ -58,7 +58,7 @@ void dumpPath(const Path & path, Sink & sink,
 struct ParseSink
 {
     virtual void createDirectory(const Path & path) { };
-    
+
     virtual void createRegularFile(const Path & path) { };
     virtual void isExecutable() { };
     virtual void preallocateContents(unsigned long long size) { };
@@ -66,10 +66,14 @@ struct ParseSink
 
     virtual void createSymlink(const Path & path, const string & target) { };
 };
-    
+
 void parseDump(ParseSink & sink, Source & source);
 
 void restorePath(const Path & path, Source & source);
 
- 
+
+// FIXME: global variables are bad m'kay.
+extern bool useCaseHack;
+
+
 }
diff --git a/nix/libutil/serialise.cc b/nix/libutil/serialise.cc
index 6b71f52c15..9241750750 100644
--- a/nix/libutil/serialise.cc
+++ b/nix/libutil/serialise.cc
@@ -54,8 +54,24 @@ FdSink::~FdSink()
 }
 
 
+size_t threshold = 256 * 1024 * 1024;
+
+static void warnLargeDump()
+{
+    printMsg(lvlError, "warning: dumping very large path (> 256 MiB); this may run out of memory");
+}
+
+
 void FdSink::write(const unsigned char * data, size_t len)
 {
+    static bool warned = false;
+    if (warn && !warned) {
+        written += len;
+        if (written > threshold) {
+            warnLargeDump();
+            warned = true;
+        }
+    }
     writeFull(fd, data, len);
 }
 
@@ -256,4 +272,15 @@ template Paths readStrings(Source & source);
 template PathSet readStrings(Source & source);
 
 
+void StringSink::operator () (const unsigned char * data, size_t len)
+{
+    static bool warned = false;
+    if (!warned && s.size() > threshold) {
+        warnLargeDump();
+        warned = true;
+    }
+    s.append((const char *) data, len);
+}
+
+
 }
diff --git a/nix/libutil/serialise.hh b/nix/libutil/serialise.hh
index e5a9df1d05..6a6f028aa6 100644
--- a/nix/libutil/serialise.hh
+++ b/nix/libutil/serialise.hh
@@ -72,9 +72,11 @@ struct BufferedSource : Source
 struct FdSink : BufferedSink
 {
     int fd;
+    bool warn;
+    size_t written;
 
-    FdSink() : fd(-1) { }
-    FdSink(int fd) : fd(fd) { }
+    FdSink() : fd(-1), warn(false), written(0) { }
+    FdSink(int fd) : fd(fd), warn(false), written(0) { }
     ~FdSink();
     
     void write(const unsigned char * data, size_t len);
@@ -95,10 +97,7 @@ struct FdSource : BufferedSource
 struct StringSink : Sink
 {
     string s;
-    void operator () (const unsigned char * data, size_t len)
-    {
-        s.append((const char *) data, len);
-    }
+    void operator () (const unsigned char * data, size_t len);
 };
 
 
diff --git a/nix/libutil/types.hh b/nix/libutil/types.hh
index 4b5ce9a78c..160884ee1a 100644
--- a/nix/libutil/types.hh
+++ b/nix/libutil/types.hh
@@ -8,6 +8,15 @@
 
 #include <boost/format.hpp>
 
+/* Before 4.7, gcc's std::exception uses empty throw() specifiers for
+ * its (virtual) destructor and what() in c++11 mode, in violation of spec
+ */
+#ifdef __GNUC__
+#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
+#define EXCEPTION_NEEDS_THROW_SPEC
+#endif
+#endif
+
 
 namespace nix {
 
@@ -39,10 +48,14 @@ protected:
 public:
     unsigned int status; // exit status
     BaseError(const FormatOrString & fs, unsigned int status = 1);
+#ifdef EXCEPTION_NEEDS_THROW_SPEC
     ~BaseError() throw () { };
     const char * what() const throw () { return err.c_str(); }
-    const string & msg() const throw () { return err; }
-    const string & prefix() const throw () { return prefix_; }
+#else
+    const char * what() const noexcept { return err.c_str(); }
+#endif
+    const string & msg() const { return err; }
+    const string & prefix() const { return prefix_; }
     BaseError & addPrefix(const FormatOrString & fs);
 };
 
diff --git a/nix/libutil/util.cc b/nix/libutil/util.cc
index 846674a29d..a4a1ddb12a 100644
--- a/nix/libutil/util.cc
+++ b/nix/libutil/util.cc
@@ -1,5 +1,8 @@
 #include "config.h"
 
+#include "util.hh"
+#include "affinity.hh"
+
 #include <iostream>
 #include <cerrno>
 #include <cstdio>
@@ -16,8 +19,6 @@
 #include <sys/syscall.h>
 #endif
 
-#include "util.hh"
-
 
 extern char * * environ;
 
@@ -125,7 +126,6 @@ Path canonPath(const Path & path, bool resolveSymlinks)
                 i = temp.begin(); /* restart */
                 end = temp.end();
                 s = "";
-                /* !!! potential for infinite loop */
             }
         }
     }
@@ -202,9 +202,10 @@ bool isLink(const Path & path)
 }
 
 
-Strings readDirectory(const Path & path)
+DirEntries readDirectory(const Path & path)
 {
-    Strings names;
+    DirEntries entries;
+    entries.reserve(64);
 
     AutoCloseDir dir = opendir(path.c_str());
     if (!dir) throw SysError(format("opening directory `%1%'") % path);
@@ -214,11 +215,21 @@ Strings readDirectory(const Path & path)
         checkInterrupt();
         string name = dirent->d_name;
         if (name == "." || name == "..") continue;
-        names.push_back(name);
+        entries.emplace_back(name, dirent->d_ino, dirent->d_type);
     }
     if (errno) throw SysError(format("reading directory `%1%'") % path);
 
-    return names;
+    return entries;
+}
+
+
+unsigned char getFileType(const Path & path)
+{
+    struct stat st = lstat(path);
+    if (S_ISDIR(st.st_mode)) return DT_DIR;
+    if (S_ISLNK(st.st_mode)) return DT_LNK;
+    if (S_ISREG(st.st_mode)) return DT_REG;
+    return DT_UNKNOWN;
 }
 
 
@@ -293,16 +304,14 @@ static void _deletePath(const Path & path, unsigned long long & bytesFreed)
         bytesFreed += st.st_blocks * 512;
 
     if (S_ISDIR(st.st_mode)) {
-        Strings names = readDirectory(path);
-
         /* Make the directory writable. */
         if (!(st.st_mode & S_IWUSR)) {
             if (chmod(path.c_str(), st.st_mode | S_IWUSR) == -1)
                 throw SysError(format("making `%1%' writable") % path);
         }
 
-        for (Strings::iterator i = names.begin(); i != names.end(); ++i)
-            _deletePath(path + "/" + *i, bytesFreed);
+        for (auto & i : readDirectory(path))
+            _deletePath(path + "/" + i.name, bytesFreed);
     }
 
     if (remove(path.c_str()) == -1)
@@ -380,6 +389,9 @@ Paths createDirs(const Path & path)
         created.push_back(path);
     }
 
+    if (S_ISLNK(st.st_mode) && stat(path.c_str(), &st) == -1)
+        throw SysError(format("statting symlink `%1%'") % path);
+
     if (!S_ISDIR(st.st_mode)) throw Error(format("`%1%' is not a directory") % path);
 
     return created;
@@ -466,10 +478,18 @@ void warnOnce(bool & haveWarned, const FormatOrString & fs)
 }
 
 
+static void defaultWriteToStderr(const unsigned char * buf, size_t count)
+{
+    writeFull(STDERR_FILENO, buf, count);
+}
+
+
 void writeToStderr(const string & s)
 {
     try {
-        _writeToStderr((const unsigned char *) s.data(), s.size());
+        auto p = _writeToStderr;
+        if (!p) p = defaultWriteToStderr;
+        p((const unsigned char *) s.data(), s.size());
     } catch (SysError & e) {
         /* Ignore failing writes to stderr if we're in an exception
            handler, otherwise throw an exception.  We need to ignore
@@ -481,12 +501,6 @@ void writeToStderr(const string & s)
 }
 
 
-static void defaultWriteToStderr(const unsigned char * buf, size_t count)
-{
-    writeFull(STDERR_FILENO, buf, count);
-}
-
-
 void (*_writeToStderr) (const unsigned char * buf, size_t count) = defaultWriteToStderr;
 
 
@@ -707,10 +721,14 @@ void AutoCloseDir::close()
 
 
 Pid::Pid()
+    : pid(-1), separatePG(false), killSignal(SIGKILL)
+{
+}
+
+
+Pid::Pid(pid_t pid)
+    : pid(pid), separatePG(false), killSignal(SIGKILL)
 {
-    pid = -1;
-    separatePG = false;
-    killSignal = SIGKILL;
 }
 
 
@@ -734,11 +752,12 @@ Pid::operator pid_t()
 }
 
 
-void Pid::kill()
+void Pid::kill(bool quiet)
 {
     if (pid == -1 || pid == 0) return;
 
-    printMsg(lvlError, format("killing process %1%") % pid);
+    if (!quiet)
+        printMsg(lvlError, format("killing process %1%") % pid);
 
     /* Send the requested signal to the child.  If it has its own
        process group, send the signal to every process in the child
@@ -801,43 +820,30 @@ void killUser(uid_t uid)
        users to which the current process can send signals.  So we
        fork a process, switch to uid, and send a mass kill. */
 
-    Pid pid;
-    pid = fork();
-    switch (pid) {
+    Pid pid = startProcess([&]() {
 
-    case -1:
-        throw SysError("unable to fork");
+        if (setuid(uid) == -1)
+            throw SysError("setting uid");
 
-    case 0:
-        try { /* child */
-
-            if (setuid(uid) == -1)
-                throw SysError("setting uid");
-
-            while (true) {
+        while (true) {
 #ifdef __APPLE__
-                /* OSX's kill syscall takes a third parameter that, among other
-                   things, determines if kill(-1, signo) affects the calling
-                   process. In the OSX libc, it's set to true, which means
-                   "follow POSIX", which we don't want here
+            /* OSX's kill syscall takes a third parameter that, among
+               other things, determines if kill(-1, signo) affects the
+               calling process. In the OSX libc, it's set to true,
+               which means "follow POSIX", which we don't want here
                  */
-                if (syscall(SYS_kill, -1, SIGKILL, false) == 0) break;
+            if (syscall(SYS_kill, -1, SIGKILL, false) == 0) break;
 #else
-                if (kill(-1, SIGKILL) == 0) break;
+            if (kill(-1, SIGKILL) == 0) break;
 #endif
-                if (errno == ESRCH) break; /* no more processes */
-                if (errno != EINTR)
-                    throw SysError(format("cannot kill processes for uid `%1%'") % uid);
-            }
-
-        } catch (std::exception & e) {
-            writeToStderr((format("killing processes belonging to uid `%1%': %2%\n") % uid % e.what()).str());
-            _exit(1);
+            if (errno == ESRCH) break; /* no more processes */
+            if (errno != EINTR)
+                throw SysError(format("cannot kill processes for uid `%1%'") % uid);
         }
+
         _exit(0);
-    }
+    });
 
-    /* parent */
     int status = pid.wait(true);
     if (status != 0)
         throw Error(format("cannot kill processes for uid `%1%': %2%") % uid % statusToString(status));
@@ -852,6 +858,32 @@ void killUser(uid_t uid)
 //////////////////////////////////////////////////////////////////////
 
 
+pid_t startProcess(std::function<void()> fun,
+    bool dieWithParent, const string & errorPrefix, bool runExitHandlers)
+{
+    pid_t pid = fork();
+    if (pid == -1) throw SysError("unable to fork");
+
+    if (pid == 0) {
+        _writeToStderr = 0;
+        try {
+            restoreAffinity();
+            fun();
+        } catch (std::exception & e) {
+            try {
+                std::cerr << errorPrefix << e.what() << "\n";
+            } catch (...) { }
+        } catch (...) { }
+        if (runExitHandlers)
+            exit(1);
+        else
+            _exit(1);
+    }
+
+    return pid;
+}
+
+
 string runProgram(Path program, bool searchPath, const Strings & args)
 {
     checkInterrupt();
@@ -867,32 +899,17 @@ string runProgram(Path program, bool searchPath, const Strings & args)
     pipe.create();
 
     /* Fork. */
-    Pid pid;
-    pid = maybeVfork();
-
-    switch (pid) {
-
-    case -1:
-        throw SysError("unable to fork");
+    Pid pid = startProcess([&]() {
+        if (dup2(pipe.writeSide, STDOUT_FILENO) == -1)
+            throw SysError("dupping stdout");
 
-    case 0: /* child */
-        try {
-            if (dup2(pipe.writeSide, STDOUT_FILENO) == -1)
-                throw SysError("dupping stdout");
-
-            if (searchPath)
-                execvp(program.c_str(), (char * *) &cargs[0]);
-            else
-                execv(program.c_str(), (char * *) &cargs[0]);
-            throw SysError(format("executing `%1%'") % program);
-
-        } catch (std::exception & e) {
-            writeToStderr("error: " + string(e.what()) + "\n");
-        }
-        _exit(1);
-    }
+        if (searchPath)
+            execvp(program.c_str(), (char * *) &cargs[0]);
+        else
+            execv(program.c_str(), (char * *) &cargs[0]);
 
-    /* Parent. */
+        throw SysError(format("executing `%1%'") % program);
+    });
 
     pipe.writeSide.close();
 
@@ -901,7 +918,7 @@ string runProgram(Path program, bool searchPath, const Strings & args)
     /* Wait for the child to finish. */
     int status = pid.wait(true);
     if (!statusOk(status))
-        throw Error(format("program `%1%' %2%")
+        throw ExecError(format("program `%1%' %2%")
             % program % statusToString(status));
 
     return result;
@@ -928,13 +945,6 @@ void closeOnExec(int fd)
 }
 
 
-#if HAVE_VFORK
-pid_t (*maybeVfork)() = vfork;
-#else
-pid_t (*maybeVfork)() = fork;
-#endif
-
-
 //////////////////////////////////////////////////////////////////////
 
 
diff --git a/nix/libutil/util.hh b/nix/libutil/util.hh
index ce2d77c19a..0ad0026711 100644
--- a/nix/libutil/util.hh
+++ b/nix/libutil/util.hh
@@ -7,6 +7,7 @@
 #include <dirent.h>
 #include <unistd.h>
 #include <signal.h>
+#include <functional>
 
 #include <cstdio>
 
@@ -63,7 +64,20 @@ bool isLink(const Path & path);
 
 /* Read the contents of a directory.  The entries `.' and `..' are
    removed. */
-Strings readDirectory(const Path & path);
+struct DirEntry
+{
+    string name;
+    ino_t ino;
+    unsigned char type; // one of DT_*
+    DirEntry(const string & name, ino_t ino, unsigned char type)
+        : name(name), ino(ino), type(type) { }
+};
+
+typedef vector<DirEntry> DirEntries;
+
+DirEntries readDirectory(const Path & path);
+
+unsigned char getFileType(const Path & path);
 
 /* Read the contents of a file into a string. */
 string readFile(int fd);
@@ -237,10 +251,11 @@ class Pid
     int killSignal;
 public:
     Pid();
+    Pid(pid_t pid);
     ~Pid();
     void operator =(pid_t pid);
     operator pid_t();
-    void kill();
+    void kill(bool quiet = false);
     int wait(bool block);
     void setSeparatePG(bool separatePG);
     void setKillSignal(int signal);
@@ -252,11 +267,19 @@ public:
 void killUser(uid_t uid);
 
 
+/* Fork a process that runs the given function, and return the child
+   pid to the caller. */
+pid_t startProcess(std::function<void()> fun, bool dieWithParent = true,
+    const string & errorPrefix = "error: ", bool runExitHandlers = false);
+
+
 /* Run a program and return its stdout in a string (i.e., like the
    shell backtick operator). */
 string runProgram(Path program, bool searchPath = false,
     const Strings & args = Strings());
 
+MakeError(ExecError, Error)
+
 /* Close all file descriptors except stdin, stdout, stderr, and those
    listed in the given set.  Good practice in child processes. */
 void closeMostFDs(const set<int> & exceptions);
@@ -264,9 +287,6 @@ void closeMostFDs(const set<int> & exceptions);
 /* Set the close-on-exec flag for the given file descriptor. */
 void closeOnExec(int fd);
 
-/* Call vfork() if available, otherwise fork(). */
-extern pid_t (*maybeVfork)();
-
 
 /* User interruption. */